COMBINATION ANTICANCER ENDOWED WITH ANTITUMOR ACTIVITY, COMPRISING ALKALOIDS OF CHELIDONIUM MAJUS

Abstract

The invention relates to a combination having antitumour activity, wherein an agent having antineoplastic activity, such as gemcitabine or temozolomide, is associated with an alkaloid of Chelidonium majus (C. majus), such as berberine, chelidonine or protopine.

Claims

1. A composition for use in the treatment of cancer, comprising a pharmaceutically acceptable quantity of an agent having antineoplastic activity and of at least one alkaloid of Chelidonium majus.

2. The composition according to claim 1, wherein the alkaloid of Chelidonium majus is comprised in the group that includes: berberine, chelidonine, protopine, and combinations thereof.

3. The composition according to claim 1, wherein the agent having antineoplastic activity comprises at least one among gemcitabine and temozolomide or its MTIC metabolite.

4. The composition according to claim 3, wherein the concentration of the alkaloid is preferably comprised between 0.1 and 10 M, whereas the concentration of temozolomide or its metabolite is lower than, or equal to, 20 M.

5. The composition according to claim 4, wherein the alkaloid is berberine and its concentration is comprised between 0.464 and 10 M.

6. The composition according to claim 4, wherein the alkaloid is chelidonine and its concentration is comprised between 0.4 and 8 M.

7. The composition according to claim 4, wherein the alkaloid is protopine and its concentration is comprised between 0.4 and 8 M.

8. The composition according to claim 3, wherein the alkaloid is berberine and its concentration is comprised between 0.4 and 10 M, less than 2 M, whereas the concentration of gemcitabine is preferably lower than or equal to 20 M.

9. The composition according to claim 3, wherein the alkaloid is chelidonine and its concentration is comprised between 7 and 10 M, less than 2 M, whereas the concentration of gemcitabine is lower than or equal to 20 M.

10. The composition according to claim 1, wherein the cancer to be treated is a pancreatic cancer when the antineoplastic agent is gemcitabine, or glioblastoma when the agent is temozolomide or its MTIC metabolite.

11. (canceled)

12. A pharmaceutical product, comprising a composition including a pharmaceutically acceptable quantity of an agent having antineoplastic activity of at least one alkaloid of Chelidonium majus, temozolomide, an alkaloid, and excipients for oral or injectable administration.

Description

[0050] The features of the invention will be specifically set out in the claims appended to the present description; such features, as well as the effects arising therefore and the advantages provided by the invention, will become more apparent in the light of the following description of a number of exemplary embodiments which are provided by way of non-limiting explanations with reference to the annexed drawings, wherein:

[0051] FIG. 1 shows the structural formulae of the alkaloids taken into account for the combination of the invention;

[0052] FIG. 2 is a graph that shows the progress of the cell metabolic activity relating to glioblastoma cells with variable concentrations of berberine, of the active metabolite of temozolomide (MTIC), and of combinations thereof;

[0053] FIG. 3 is a bar diagram that illustrates the viable cell count in assays on glioblastoma cells (U343), wherein: section (a) shows the percentage of viable cells with variable concentrations of individually administered berberine, whereas section (b) shows the percentage of viable cells following administration of active metabolite of temozolomide (MTIC) at a fixed concentration of 20 M, of berberine at the highest tested concentration (10 M), and of the combination of MTIC and berberine, wherein berberine is at the highest tested concentration;

[0054] FIG. 4 is a bar diagram that illustrates the percentage of viable cells in assays on glioblastoma cells (U343), wherein: (a) refers to control and treatment with MTIC (at a fixed concentration), (b) refers to variable concentrations of berberine, and (c) refers to treatments with three combinations of active metabolite of temozolomide (MTIC, fixed concentration of 20 M) and berberine at the three different concentrations taken into account;

[0055] FIG. 5 is a bar diagram that shows the percentage of viable cells in assays on human dermal fibroblasts (HDF), (a) when there are treated with a changing concentration of berberine administered individually whereas (b) illustrates the percentage of viable cells following administration of berberine at the highest concentration tested (10 microM), the temozolomide active metabolite (MTIC) used at a fixed concentration (equal to 20 microM), and the combination of MTIC with berberine, in which berberine is present at the highest concentration tested;

[0056] FIG. 6 is a bar diagram that shows the percentage of viable cells in assays on human dermal fibroblasts (HDF), when treated (a) with a fixed concentration of MTIC, (b) with berberine at three different concentrations, and (c) with combinations of MTIC and berberine, wherein the latter is used at the three different concentrations at which it was individually tested;

[0057] FIG. 7 contains two graphs that schematize the tread of a parameter (therapeutic favourability indexTFI, defined in detail in EXAMPLE 2), consisting of the ratio between the percentage of tumour cells and the percentage of cells chosen as a non-tumour cell model that remain viable following the various assayed treatments;

[0058] FIG. 8 is a graph that shows the progress of the metabolic activity relating to glioblastoma cells with variable concentrations of chelidonine, of the active metabolite of temozolomide (MTIC), and of the combination thereof;

[0059] FIG. 9 is a graph that shows the progress of the metabolic activity relating to glioblastoma cells with variable concentrations of protopine, of the active metabolite of temozolomide (MTIC), and of the combination thereof;

[0060] FIG. 10 is a graph that shows the progress of the metabolic activity relating to pancreatic tumour cells (MIA PaCa-2) with variable concentrations of berberine, of gemcitabine, and of the combination thereof;

[0061] FIG. 11 is a graph that shows the percentage of pancreatic tumour cells (MIA PaCa-2) that remain viable after the following treatments: (a) with gemcitabine alone (used at a fixed concentration of 20 M), (b) with variable concentrations of berberine (0.4 M, 2.0 M, 10.0 M and 50.0 M), and (c) following treatments with three combinations containing gemcitabine (at a fixed concentration) and berberine at concentrations of 0.4 M, 2.0 M, 10.0 M;

[0062] FIG. 12 is a graph that shows the progress of the cell metabolic activity relating to MIA PaCa 2 cells after the following treatments: (a) with Ukrain alone, with gemcitabine alone, and with an association between Ukrain and gemcitabine, (b) with gemcitabine alone, with berberine alone, and with an association between gemcitabine and berberine, (c) with gemcitabine alone, with chelidonine alone, and with an association between gemcitabine and chelidonine, and (d) with gemcitabine alone, with protopine alone, and with an association between gemcitabine and protopine at variable concentrations.

[0063] With reference to the drawings, the alkaloids taken into consideration in the first figure are of the type commercially available (in this case, from Sigma-Aldrich) and have the highlighted structure.

[0064] The same applies to the antitumour drugs that were assayed in combination with the alkaloids, i.e. gemcitabine (supplied by Sigma-Aldrich) and the active metabolite of temozolomide MTIC [5-(3-methyl-1-triazeno)imidazole-4-carboxamide], supplied by Santa Cruz Tech.

[0065] In order to evaluate the effects of the antitumour combination of the invention, cellular viability was taken into account as a switable reference parameter, observed after in vitro application of the antitumour combination and estimated in terms of dehydrogenase activity. Moreover, in the case of treatments on U343 cells with berberine and associations thereof with MTIC, and in the case of treatments on MIA PaCa-2 cells with berberine and associations thereof with gemcitabine, also the percentage of viable cells, estimated via cell count, was taken into consideration.

[0066] For sake of completeness' of information and for the purpose of evaluating the differential cytotoxicity exerted both by the individual components of the combinations and by the combinations themselves on tumour and normal cells, the same treatments tested on U343 cells were also conducted on human dermal fibroblasts (HDF), chosen as a model of cells not concerned by tumour pathologies; this allowed, in the case of treatments tested on U343 cells, evaluations of the differential effects of the tested agents against tumour cells and against a model of normal cells, in accordance with the invention.

[0067] Furthermore, cell viability was estimated in two different ways: dehydrogenase assay, based on the reaction of formazan (WST-1), and viable cell count with Neubauer chamber after treatment with Trypan blue.

[0068] The results obtained showed a sensible reduction in the viability of tumour cells when the alkaloids are used in combination with antitumour drugs; such a reduction is surprisingly present in the case of application to glioblastoma cells, also for low concentrations of the compound combination.

[0069] In the case of pancreatic tumour cells, a reduction in their viability was observed with increased concentrations of the combination of gemcitabine and the alkaloid berberine.

[0070] A comparison with the application of the same antitumour combinations on non-tumour cells, such as human dermal fibroblasts (HDF), surprisingly showed that the combination, which per se proves to be more effective than the individual components on tumour cells, is also significantly less toxic on the HDF cells chosen as a normal cell model.

[0071] What represents an important aspect of the invention is the discovery of the differential reduction effect on cell viability, based on which it can be stated that the cytotoxicity produced on U343 cells by the association of MTIC with berberine is significantly more marked than the cytotoxicity produced by the same association on the normal HDF cell model, compared to the effects produced by the single components taken individually (MTIC and berberine). This makes the combination suitable for therapeutic uses.

[0072] During the work conducted for this patent application, the presence in Ukrain of the 7 alkaloids contained in the extracts of C. majus mentioned in International patent applications WO2013084162 and WO2013084163 was investigated for sake of scrupulousses, to quantify them in Ukrain if they were present. For sake of completeness, the following table shows the results of our quantitative study on the alkaloids of C. majus which are of interest for the study described herein.

TABLE-US-00002 Berberine Chelidonine Protopine Molar Conc. Molar Conc. Molar Conc. Ukrain 4.69 10.sup.6 7.71 10.sup.5 3.24 10.sup.4

[0073] As a confirmation of the extreme variability of the responses evoked by a same molecule or by a same combination of individual components on different cell lines, even of the same type of tumour pathology, which emerges from an analysis of the scientific literature, we have deemed it useful to conduct specific experiments, the results of which are shown in FIG. 12 and commented below.

[0074] For example, the association with gemcitabine of each one of the alkaloids mentioned in this application represents a novelty, in that the experiments have shown that the effects of the association of Ukrain with gemcitabine, on one of the two investigated cell lines (MIA PaCa-2pancreatic cancer), are very different from the effects produced by binary associations of gemcitabine with each one of the three alkaloids taken into account (see graphs shown in FIG. 12), and this finding means that the behaviour of the associations was not foreseeable on the basis of prior knowledge [e.g. from Gansauge et al. 2002, Chinese patent application CN 103 372 210, or from Fan Li-Xia Biochimica et Biophysica Acta (BBA) 2013, Ernst et al. 2005].

[0075] Indeed, the graph (a) in FIG. 12 shows that, when Ukrain (yellow line) is administered individually to MIA PaCa-2 cells at percent concentrations higher than 0.005% (v/v), cell viability increases (this effect is opposite to the desired one), and then it remains relatively constant starting from a percent concentration of 0.05% until the highest tested concentration (5%) is reached. The concentration of Ukrain is expressed as a percent volume relative to the sample in solution directly supplied by the producer.

[0076] The binary association of Ukrain with gemcitabine begins to cause a reduction in the viability of MIA PaCa-2 cells (desired effect) starting from a concentration slightly lower than 10.sup.55 M of gemcitabine and slightly lower than 0.5% of Ukrain.

[0077] Binary associations of gemcitabine with berberine [FIG. 12 (b)] and of gemcitabine with chelidonine [FIG. 12 (c)] show a similar reduction in the viability of MIA PaCa-2 cells (desired effect) in the area of the highest concentrations considered in the graph, while the binary association of gemcitabine with protopine [FIG. 12 (d)] seems to increase cell viability (undesired effect) in an irregular manner in most of the assayed concentrations, without ever causing it to diminish.

[0078] As regards the effects produced on MIA PaCa-2 cells by combinations of individual alkaloids of C. majus with gemcitabine, it can be concluded that, while binary associations of gemcitabine with berberine and with chelidonine produce, at certain concentrations only and with different profiles, similar effects consisting of a reduction in the viability of the MIA PaCa-2 cells compared to the treatment with gemcitabine alone or with the individual alkaloid, protopine associated with the same molecule (gemcitabine) actually causes an increase in the viability of the same cells.

[0079] The substantial and unpredictable difference that it was been observed between the effects produced by Ukrain and the effects produced by individual alkaloids, is also supported by the differential results observed and described in a previously mentioned article [Habermehl et al. 2006] concerning to the effects produced on Jurkat T-lymphoma cells by the alkaloids under examination within that context (including chelidonine and protopine, but not berberine).

EXAMPLE 1 (EXPERIMENTS BASED ON WST-1 ASSAY)

[0080] Alkaloids of C. majus (berberine, chelidonine, protopine), gemcitabine, Trypsin-EDTA enzyme, fetal bovine serum (FBS), dimethyl sulfoxide (DMSO), L-Glutamine and Trypan blue were purchased from Sigma-Aldrich.

[0081] Metabolite (5-(3-methyl-1-trizeno)imidazole-4-carboxamide) of temozolomide MTIC was supplied by Santa Cruz Tech.

[0082] MIA PaCa-2 pancreatic tumour cell lines and glioblastoma cell lines (U343) were initially obtained from the Pharmacy Department of the University of Pisa and subsequently purchased.

[0083] Cell Proliferation Reagent (WST-1) was purchased from Roche Diagnostics GmbH (Manneheim, Germany), whereas human dermal fibroblast cells (HDF) came from ATCC.

[0084] All agents were dissolved into DMSO and preserved at 20 C. for a short time prior to use. The cells were cultivated in monolayer culture in DMEM ground (Life Technologies), integrated with 5% fetal bovine serum (FBS), 1% L-glutamine and 1% antibiotics (penicillin-streptomycin from Lonza) at 37 C. in humidified 5% CO.sub.2 atmosphere.

[0085] The MIA PaCa-2 pancreatic tumour cells and the U343 glioblastoma cells were cultured in 96-well plates for cell culture until an approximate 70-80% confluence, after 4 hours and treated with the agents. The variation of cell viability was estimated after 48 hours via WST assay, wherein WST-1 was used as a reagent. The absorbance reading was taken at 450 nm. Measurements were taken for different agent concentrations on:

[0086] (a) untreated cells 0 hours after adhesion (control at time zero, control.sub.t0),

[0087] (b) untreated cells after a 48-hour interval from adhesion (control after 48 hours, control.sub.t48),

[0088] (c) cells treated with the agents of interest and observed 48-hour after adhesion.

[0089] The cell viability variation was set to 0% for control cells at t=0; it was set to 100% for control cells at t=48 hours. All agent concentrations were assayed in triplicate.

[0090] The following tables show the data from which the illustrated graphs were derived.

[0091] In particular, Table 1 shows the data relating to berberine, MTIC and the combination thereof, applied to the U343 glioblastoma cell line and obtained via WST assay, from which the graph of FIG. 2 was derived. The latter indicates on the X axis the concentration of the assayed agents. As far as the binary association is concerned, its components have a fixed 50/50 ratio.

TABLE-US-00003 TABLE 1 Type of Experiment: WST assay Cell line: U343 (glioblastoma) Compounds: Berberine MTIC MTIC + Berberine Concentrations: 0.1 M-10M 0.1 M-10 M Equimolar Berberine MTIC Ber + MTIC (viability %) SEM n (viability %) SEM n (viability %) SEM n 10 M 10.3533 2.79164 3 34.009 3.4029 3 23.25687 15.5957 3 4.642 M 11.3394 3.87418 3 25.991 5.2831 3 11.56095 2.16065 3 2.154 M 15.4889 11.3021 3 27.2523 2.6138 3 19.83807 2.45443 3 1 M 27.3008 15.3451 2 24.9099 2.4577 3 14.30499 4.78676 3 0.464 M 36.3599 8.01151 2 16.8018 3.0341 3 29.32973 7.17763 3 0.215 M 12.3254 3.98817 3 21.1712 5.0166 3 24.2915 11.4761 3 0.1 M 23.2128 2.8618 3 24.009 7.1852 3 5.48808 2.29948 3

[0092] From Table 1 it emerges that, in U343 cells, administration of MTIC increases the cell metabolic activity in an irregular manner (from approx. 115 up to 130%, depending on MTIC concentration), and that administration of berberine alone causes an increase, though not a very marked one, in the metabolic activity (from approx. 110 to 136%). Equimolar combinations of MTIC and berberine show, on the contrary, a reduction in the cell metabolic activity (between 90 and 70%), which at certain concentrations appears to be relevant.

[0093] Table 2 shows the data relating to, respectively, chelidonine, MTIC and the combination thereof, applied to the U343 glioblastoma cell line and obtained via WST assay, from which the graph of FIG. 8 was derived; the variables shown on the X and Y axes of the latter are the same as those in the graph of FIG. 2.

TABLE-US-00004 TABLE 2 Type of Experiment: WST assay Cell line: U343 (glioblastoma) Compounds: Chelidonine MTIC MTIC + Chelidonine Concentrations: 0.1 M-10 M 0.1 M-10 M Equimolar Chelidonine MTIC Chel + MTIC (viability %) SEM n (viability %) SEM n (viability %) SEM n 10 M 14.3799 1.97947 3 34.009 3.4029 3 31.94325 8.51648 3 4.642 M 24.4335 4.67778 3 25.991 5.2831 3 55.546 2.35753 3 2.154 M 40.0495 0 1 27.2523 2.6138 3 44.96991 7.95217 3 1 M 25.9168 0.47518 3 24.9099 2.4577 3 39.29492 3.96159 3 0.464 M 3.74948 11.7124 3 16.8018 3.0341 3 37.44626 3.3534 2 0.215 M 22.4145 2.15087 3 21.1712 5.0166 3 17.92777 3.61314 3 0.1 M 2.4722 11.2485 2 24.009 7.1852 3 13.3706 1.53393 3

[0094] From Table 2 it emerges that, in the same U343 cells, administration of chelidonine alone produces effects characterized by an irregular trend, with a reduction, at specific concentrations only, in the metabolic activity. Equimolar binary combinations of MTIC and chelidonine cause a significant decrease in the metabolic activity (between 85 and 45%) in a wide range of tested concentrations.

[0095] Table 3 shows the data relating to, respectively, protopine, MTIC and the combination thereof, applied to the U343 glioblastoma cell line and obtained via WST assay, from which the graph of FIG. 9 was derived; the variables shown on the X and Y axes are the same as those in the graph of FIG. 2.

TABLE-US-00005 TABLE 3 Type of Experiment: WST assay Cell line: U343 (glioblastoma) Compounds: Protopine MTIC MTIC + Protopine Concentrations: 0.1 M-10 M 0.1 M-10 M Equimolar Protopine MTIC Pro + MTIC (viability %) SEM n (viability %) SEM n (viability %) SEM n 10 M 7.968 8.62211 3 34.009 3.4029 3 30.73356 4.50149 3 4.642 M 27.3609 9.83487 3 25.991 5.2831 3 44.09781 4.99556 3 2.154 M 16.231 18.0266 3 27.2523 2.6138 3 44.98314 7.70717 3 1 M 12.0152 14.2498 3 24.9099 2.4577 3 47.84991 3.96806 3 0.464 M 9.1484 2.11928 3 16.8018 3.0341 3 34.19056 5.36789 3 0.215 M 2.02362 5.50826 3 21.1712 5.0166 3 19.13996 4.56248 3 0.1 M 5.8179 11.2637 3 24.009 7.1852 3 9.73862 2.04501 3

[0096] From Table 3 it emerges that, in the same U343 cells, administration of protopine alone causes a slight increase in the metabolic activity (up to 130%), whereas the equimolar binary combination of MTIC and protopine causes a decrease in the metabolic activity (between 80 ad 50%) at all of the assayed concentrations, which turns out to be particularly marked at concentrations in the range of 10.sup.6.5 M to 10.sup.5.5 M.

[0097] Table 4 shows the data of berberine, gemcitabine and the combination thereof, applied to the MIA PaCa-2 pancreatic tumour line and obtained via WST assay, from which the graph of FIG. 10 has been drawn.

TABLE-US-00006 TABLE 4 Type of Experiment: WST assay Cell line: MIA PaCa-2 (pancreatic carcinoma) Samples: Berberine Gemcitabine Gem + Berberine Concentrations: 0.1 M-10 M 0.1 M-10 M Equimolar Berberine Gemcitabine Ber + Gem (viability %) SEM n (viability %) SEM n (viability %) SEM n 10 M 64.76 8.38 2 2.25 4.4 3 84.26 3.28 3 4.642 M 69.29 5.96 2 24.16 11.47 3 57.97 3.24 2 2.154 M -3.42 7.85 2 17.64 7.84 3 6.44 2.72 2 1 M 16 3.79 3 3.26 2.7 3 1.18 8.53 2 0.464 M 10.41 7.66 3 12.56 21.83 2 12.22 6.94 3 0.215 M 5.73 3.05 3 27.87 11.67 3 13.33 1.93 3 0.1 M 11.32 3.96 3 54.72 7.33 3 5.08 2.35 3

[0098] From Table 4 it emerges that, in MIA PaCa-2 cells, wherein the treatment with gemcitabine alone causes an essentially negligible increase in the cell metabolic activity, individually administered berberine causes a significant decrease in the metabolic activity only starting from concentrations slightly lower than 10 M (5 Log M) (approx. 50%). Equimolar combinations of gemcitabine and berberine produce a considerable reduction in the metabolic activity in a dose-dependent manner, starting from individual component concentrations of approx. 4.64 M (5.33 Log M) and going towards higher concentrations. The treatment with the combination wherein the individual components' concentration is 4.64 M reduces the metabolic activity to 57%, while the treatment with the combination wherein the individual components' concentration is 10 M reduces the metabolic activity to 21%.

[0099] It must be pointed out that, as far as the diagnostic value of the WST assay is concerned, instead of generally speaking of cell viability it would be appropriate to refer to cell metabolic activity monitored via cellular dehydrogenase activity.

EXAMPLE 2 (EXPERIMENTS BASED ON U343 CELL COUNT)

[0100] The U343 cells and the HDF cells were cultivated in T25 flasks and treated with the agents after reaching a confluence of 90%. After 48 hours of treatment, the cells were detached with trypsin-EDTA and suspended in medium consisting of 50% DMEM and 50% Trypan blue. The number of viable cells after each treatment was estimated by using the Neubauer counting chamber, excluding cells positive to Trypan blue. At least three countings were made for each treatment.

[0101] The percentage of viable cells compared to the control was determined by the ratio between the number of treated cells and the number of untreated cells.

[0102] The following tables show the data from which the graphs of FIGS. 3, 4, 5, 6 and 7 were derived.

[0103] In particular, the following Table 5 shows the data relating to berberine, MTIC and three combinations thereof (wherein the MTIC concentration is kept fixed, while the berberine concentration varies), applied to the U343 glioblastoma cell line. The data were obtained via cell counting assay, from which the bar diagrams of FIGS. 3 and 4 were derived.

TABLE-US-00007 TABLE 5 Type of Experiment: Cell counting Cell line: U343 (glioblastoma) Compounds: Compound I MTIC MTIC + Compound I Concentrations: 0.464 M-10 M 20 M 0.464 M-10 M/20 M The Figure summarizes the results of the cell counting experiment relating to U343 cells subjected to berberine treatments for 48 hours. Ber Ber Ber MTIC MTIC + MTIC + MTIC + Untreated 0.464 M 2.154 M 10 M 20 M Ber 0.4 M Ber 2 M Ber 10 M 100% 94% 82.6% 59.8% 69.7% 65.6% 41.5% 44.8%

[0104] Table 6 below shows the data relating to berberine, MTIC and three combinations thereof (wherein the MTIC concentration is kept fixed, while the berberine concentration varies), applied to the HDF cell line (normal non-tumour cell model). The data were obtained via cell counting assay, from which the bar diagrams of FIGS. 5 and 6 were derived.

TABLE-US-00008 TABLE 6 Type of Experiment: Cell counting Cell line: HDF Compounds: Compound I MTIC MTIC + Compound I Concentrations: 0.464 M-10 M 20 M 0.464 M-10 M/20 M The Figure summarizes the results of the cell counting experiment relating to HDF cells subjected to berberine treatments for 48 hours. Ber Ber Ber MTIC MTIC + MTIC + MTIC + Untreated 0.464 M 2.154 M 10 M 20 M Ber 0.4 M Ber 2 M Ber 10 M 100% 82.65 70.41 67.35 106.12 77.55 77.55 85.71

[0105] The graph of FIG. 3, which concerns the treatment of U343 cells, is divided into two parts: the part on the left (a), relating to berberine only, shows on the X axis the berberine concentration and on the Y axis the percentage of viable cells, whereas the part on the right (b) shows the percentage of viable cells after a treatment with the berberine-MTIC combination, wherein berberine has a concentration of 10 M, at which concentration berberine alone causes the presence of a lower percentage of viable cells. The same graph also shows, for comparison, the percentages of viable cells detected after treatments with 10 M berberine alone and with 20 M MTIC alone.

[0106] The graph of FIG. 4 shows the effects of treatments carried out on U343 cells, indicating, in addition to the control, the percentage of viable cells after treatments with (a) MTIC administered individually at a concentration of 20 M, (b) berberine administered individually at three different concentrations (0.464 M, 2.154 M and 10 M), and (c) three binary combinations of 20 M MTIC with berberine at the above-mentioned three different concentrations (Combination I, containing 0.464 M berberineCombination II, containing 2.15 M berberineCombination III, containing 10.0 M berberine).

[0107] The graph of FIG. 5 shows the percentage of viable cells in experiments carried out on HDF cells, chosen as a normal cell model, after the same treatments already described for the U343 cells (and partly summarized in the graph of FIG. 3b).

[0108] The graph of FIG. 6 shows the effects of treatments carried out on HDF cells chosen as a normal (non-tumour) cell model, indicating, in addition to the control, the percentage of viable cells after treatments with (a) MTIC administered individually at a concentration of 20 M, (b) berberine administered individually at three different concentrations (0.464 M, 2.154 M and 10 M), and (c) three binary combinations of 20 M MTIC with berberine at the above-mentioned three different concentrations (Combination I, containing 0.464 M berberineCombination II, containing 2.15 M berberineCombination III, containing 10.0 M berberine).

[0109] It is important to highlight the fact that cell counting experiments are especially useful to allow estimating the percentage of viable cells (U343 glioblastoma cells and HDF cells, chosen as a normal cell model) that can be observed after the treatments, and that the comparison between the effects on tumour cell lines and those on normal cells allows evaluating, at the same time, the cytotoxicity on the tumour cell line (desired effect) and the cytotoxicity on the normal cell model (undesired effect).

[0110] For the purpose of properly interpreting the results of the experiments as a whole, it was therefore useful to define an index that was called Therapeutic Favourability Index (TFI), consisting of the ratio between the percentage of viable cells, measured against the control, found after the treatment with the samples under examination in the U343 cells (the proliferation of which must be inhibited) and in the HDF cells (the proliferation of which should ideally remain unchanged compared to the respective control).

[0111] Table 7 shows the percentages of viable cells relative to the control that were observed in experiments conducted with U343 cells and HDF cells after administration of MTIC alone (the active metabolite of Temozolomide) (at a concentration of 20 M), berberine alone (at concentrations of 0.464 M, 2.15 M and 10.0 M, respectively), and combinations consisting of MTIC (20 M) and berberine (0.464 M of berberine in combination I, 2.15 M of berberine in combination II, and 10.0 M of berberine in combination III, respectively). For each treatment, the therapeutic favourability index (TFI) is also shown, as defined above.

TABLE-US-00009 TABLE 7 TFI index % proliferation % proliferation U343/HDF of U343 of HDF % proliferation Assayed agent against control against control ratio MTIC (20 M) 69.70 106.12 0.657 Berberine (0.464 M) 94.00 82.65 1.137 Berberine (2.154 M) 82.60 71.41 1.173 Berberine (10.0 M) 59.80 67.35 0.888 Combination I 65.60 77.55 0.846 MTIC (20 M) + Berberine (0.464 M) Combination II 41.50 77.55 0.535 MTIC (20 M) + Berberine (2.154 M) Combination III 44.80 85.71 0.523 MTIC (20 M) + Berberine (10.0 M)

[0112] FIG. 7 shows two graphs that schematize the trend of the TFI parameter for each one of the agents used in the assays. In bar graph (a), the light blue bars refer to MTIC (the concentration of which was set to 20 M for both individual administration and combinations with berberine), the magenta bars refer to berberine administered individually (and assayed at three different concentrations, i.e. 0.464 M, 2.154 M and 10 M), and the green bars refer to the three combinations wherein the MTIC concentration was kept constant and the berberine concentrations varied in accordance with those used for individual administration of the same. The same values are shown in the dot graph (b). It may be useful to remind that the TFI parameter allows estimating the ratio between desired cytotoxicity (on U343 cells) and undesired cytotoxicity (on HDF cells used as a normal cell model). The lower the value of the TFI parameter, the more the assayed agent is adequate for therapeutic use, since this parameter measures the ratio between desired cytotoxicity (on tumour cells) and undesired cytotoxicity (on the cells of the non-tumour model).

[0113] According to the values of the TFI parameter, it turns out that the combination II, and especially the combination III, are expected to produce a significantly better therapeutic effect than administration of temozolomide alone, which reaches the cell in the organism in the form of its MTIC metabolite, and administration of berberine alone. It can also be observed that, on the pair consisting of the U343 cell line (glioblastoma cells) and the HDF cell line (normal cell model), berberine alone would have a worse TFI value than the active metabolite of temozolomide (MTIC). This contributes to giving a character of novelty to the work described herein, compared to the contents of [Liu et al. 2015], published on line on Dec. 12, 2014.

[0114] The data reported in [Liu et al. 2015] do not appear to be directly comparable with the results described herein. In such article, in fact, reference is made to the fact that berberine can markedly stop the proliferation of glioblastoma cells more efficiently than temozolomide, since it induces senescence in human glioma cells. More specifically, for the work described in such article the U87, U251 and U118 glioblastoma cell lines were used in addition to the SGH.44 line, and the agents were assayed individually only, at concentrations higher than those considered in the present work.

[0115] More in detail, in such article the berberine concentrations used were in the range of 15 to 150 M. Instead, in the study presented herein, wherein the effects of the agents of interest on the U343 glioblastoma cell line were observed, the maximum berberine concentration used for both individual administration and combinations with 20 M MTIC did not exceed the value of 10 M.

[0116] Furthermore, in [Liu et al. 2015] the effects of berberine and those of temozolomide were compared, also in the in vitro experiments (experiments on cells), by directly using temozolomide (prodrug), without taking into account the fact that, after administration to a living organism, the molecule that reaches the cell to exert its effect is actually its active metabolite MTIC. Therefore, the use of temozolomide is correct for in vivo experiments, but, based on the above consideration, the choice of the temozolomide prodrug does not appear to be appropriate for in vitro experiments. In addition, in [Liu et al. 2015] the temozolomide directly administered to the cells was used in the concentration range of 40 to 320 M. In the study presented herein, instead, the MTIC concentration used for both individual administration and combinations with berberine at the three different concentrations specified for the Combinations I, II and III was 20 M.

[0117] In the study described herein, temozolomide was also assayed by direct administration to U343 cells and HDF cells, for the purpose of observing the direct effect of temozolomide on such cells. It was possible to observe that direct administration of temozolomide does not cause significant variations (within the measurement accuracy limits) in the percentage of viable U343 cells, while it causes a decrease up to a 60-70% reduction in the percentage of viable HDF cells.

[0118] In the study presented herein, in order to compare the effects exerted on the cells by the administration of temozolomide, it was deemed to be more appropriate to use the active metabolite of temozolomide (MTIC), since this is the molecule that actually reaches the cell after administration of temozolomide to a living organism (whether a human being or a test animal).

[0119] As aforementioned, in [Liu et al. 2015] the concentrations used for the agents under investigation are higher than those used in the study described herein, and, since one of the objects of this study was to identify a combination of agents that would prove effective for the treatment of glioblastoma while reducing the inevitable side effects due to administration of temozolomide, the contribution of this study to finding a therapy that, as a whole, is more favourable for the patients takes a character of novelty. This is true not only because it suggests the use of combinations as opposed to berberine alone, but also because it suggests the use of reduced drug dosages.

[0120] It is also important to point out that it cannot be automatically predicted that the combination of berberine and MTIC (in in vitro experiments) or the administration (in vivo) of combinations of berberine and temozolomide will cause an effect that is the sum of the effects individually exerted by the single components of the combination. In fact, administration of a combination of two or more components may give (in a way that cannot be foreseen a priori) the following:

[0121] (a) an enhanced effect, i.e. an effect which is greater than the sum of the effects produced by the single components administered individually (positive synergism),

[0122] (b) a null effect or an effect which is lower than that produced by individual administration of the single components (negative synergism), or

[0123] (c) an effect which is opposite to that exerted by individual administration of the components (inverse synergism). An opposite effect is meant to be, for example, an effect of stimulation of cell proliferation as opposed to an inhibitory effect.

[0124] The a priori unpredictability of the effect of any combination of a number of components, compared to the effects produced by the single components, is a fact that is universally recognized by the scientific community and that stands at the basis of the studies on synergism (which, as aforementioned, can be positive, negative or inverse). This is also testified by the fact that a simple bibliographical search made in the PubMed database (http://www.ncbi.nlm.nih.gov/pubmed/) by using synergism as a keyword will return as many as 68,501 documents, while a similar search made by using positive synergism as keywords will return as many as 3,474 documents, a similar search made by using negative synergism as keywords will return as many as 2,645 documents, and a similar search made by using inverse synergism as keywords will return 140 documents (searches updated to Jan. 24, 2016). The above considerations support the view according to which the huge number of documents about synergism in general suggests that this is a very common phenomenon when combinations of different molecules are used for studying their biological effects.

EXAMPLE 3 (EXPERIMENTS BASED ON MIA PACA-2 CELL COUNT)

[0125] The MIA PaCa-2 cells were cultivated in T25 flasks and treated with the agents after reaching a confluence of 90%. After a 48 hours treatment, the cells were detached with trypsin-EDTA and suspended in medium consisting of 50% DMEM and 50% Trypan blue. The number of viable cells after each treatment was estimated by using the Neubauer counting chamber, excluding those cells which turned out positive to Trypan blue. At least three counts were made for each treatment.

[0126] The percentage of viable cells relative to the control was determined by the ratio between the number of treated cells and the number of untreated cells.

[0127] The following table shows the data from which the graph of FIG. 11 was derived.

[0128] In particular, Table 8 shows the data of berberine, gemcitabine and three combinations thereof (wherein the gemcitabine concentration was kept fixed, whereas the berberine concentration varied), applied to the MIA PaCa-2 pancreatic cancer cell line. The data were obtained via cell counting assay, from which the bar diagram of FIG. 11 was then obtained.

TABLE-US-00010 TABLE 8 Ber Ber Ber Ber Gemcitab Gemcitab + Gemcitab + gencitab + Untreated 0.4 M 2.0 M 10 M 50 M 20 M Ber 0.4 M Ber 2.0 M Ber 10.0 M 100% 88% 51% 33% 24% 33% 15% 18% 13%

[0129] The bar diagram of FIG. 11 shows the effects of treatments carried out on MIA PaCa-2 cells, indicating, in addition to the control, the percentage of viable cells after treatments with (a) gemcitabine administered individually at a concentration of 20 M, (b) berberine administered individually at four different concentrations (0.4 M, 2.0 M, 10.0 M and 50 M), and (c) three binary combinations of 20 M gemcitabine with berberine at three of the above-mentioned different concentrations (Combination I.sub.gem-ber, containing 0.4 M berberineCombination II.sub.gem-ber, containing 2.0 M berberineCombination III.sub.gem-ber, containing 10.0 M berberine).

[0130] The results show that berberine, when administered individually, produces, already at the 10 M concentration, the same reduction in the percentage of viable cells as that produced by 20 M gemcitabine (in both cases, after the two treatments the percentage of viable cells is reduced to a little more than 30%). This datum can be very interesting, if we consider that berberine belongs to food supplements, whereas gemcitabine implies, just like all other antitumour agents, inevitable and undesired toxicity.

[0131] However, the surprising fact is that the administration of combinations comprising 20 M gemcitabine and berberine at concentrations in the range of 0.4 and 10 M further reduces the number of viable cells to less than 20%.

[0132] Since the aim of the study described herein was to try to identify combinations comprising drugs already used for clinical purposes and alkaloids of C. majus which could provide advantageous therapeutic effects compared to the treatments known in the art, the observed effect due to the use of the three above-described combinations (I.sub.gem-ber, II.sub.gem-ber and III.sub.gem-ber) seems to fully achieve the targets of the conducted research.

[0133] The use of combinations of Ukrain and gemcitabine in patients suffering from pancreatic cancer is known, but the employment of such an association has only been described in clinical use (in this respect, see Gansauge et al. [2007]). However, so far no study has been conducted, to the present Applicants' knowledge, which indicates the haematic concentrations of the individual components of Ukrain in patients treated with Ukrain or combinations thereof with gemcitabine.

[0134] Among the in vitro studies based on Ukrain associations, the study of Kurochkin et al. [2000] has been already mentioned above, which however relates to associations of Ukrain with etoposide, assayed in CHO cells.

[0135] Other in vitro studies on pancreatic cancer cell lines that involve Ukrain have been mentioned above. In this regard, it must be pointed out that Gagliano et al. [2012] describe in vitro studies on three pancreatic cancer cell lines (HPAF-II, HPAC and PL45) treated with Ukrain alone at concentrations of 5, 10 and 20 M. This study provides important indications about the mechanism through which Ukrain performs its action, but it does not examine Ukrain in combination with other known molecules. On the same matter, it must also be pointed out that Funel et al. [2010] describe other in vitro studies on the same three pancreatic cancer cell lines (also in this case treated with 5, 10 and 20 M Ukrain); also this study provides important information about the action mechanisms of Ukrain, without however examining the effects of Ukrain in combination with other known molecules.

[0136] Considering the fact that, at least in clinical use, combinations of Ukrain with gemcitabine have already been described for the treatment of pancreatic cancer, it is important herein to focus the attention on the results of an in vitro study, already mentioned above, that was carried out by the present Applicants in order to evaluate how the effects of binary combinations of gemcitabine with Ukrain or with each one of the three alkaloids of interest for the work described herein, may differ from one another.

[0137] Said study, the results of which are summarized in FIG. 12, demonstrates that the effect exerted on MIA PaCa-2 cells by a combination of Ukrain with gemcitabine is considerably different from the effects exerted by its individual components (berberine, chelidonine and protopine) used in binary combinations with gemcitabine. In fact, as already described, it can be observed that the combinations of Ukrain and gemcitabine produce a reduction in the dehydrogenase activity in MIA PaCa-2 cells that reaches approx. 50% when combinations are administered in which gemcitabine reaches a maximum concentration of 10 M and Ukrain reaches a maximum concentration of 5%, expressed as volume/volume (v/v). A reduction of some interest in the dehydrogenase activity begins to be observed for combinations in which gemcitabine has a concentration starting from 10.sup.55 M and Ukrain has a concentration starting from 0.5% (v/v).

[0138] Within the concentration range wherein Ukrain appears in the binary combination with gemcitabine [5%-0.5% (v/v)], the three alkaloids of interest for the work described herein are approximately present at the following concentrations:

[0139] Berberine: approx. 0.2-0.02 M

[0140] Chelidonine: approx. 4-0.4 M

[0141] Protopine: approx. 160-16 M

[0142] The binary combination of gemcitabine and berberine produces an effect of reduction in the dehydrogenase activity in MIA PaCa-2 cells ranging from approx. 75% to 25% when the (equimolar) concentrations of the two components vary in the range of 10.sup.5.0 M [10 M] to 10.sup.5.5 M.

[0143] The binary combination of gemcitabine and chelidonine produces an effect of reduction in the dehydrogenase activity in MIA PaCa-2 cells that begins to become interesting (approx. 75%) only starting from concentrations close to 10 M.

[0144] The binary combination of gemcitabine and protopine produces an effect, opposite to the desired one, of increasing the dehydrogenase activity in MIA PaCa-2 cells, with an irregular trend at all of the assayed concentrations.

[0145] Thus, in vitro (or in vivo) data relating to the use of combinations of Ukrain with gemcitabine cannot be considered to be anticipatory of the study described herein, because the effects of the binary combinations of the three alkaloids described herein with gemcitabine cannot be predicted on the basis of the effect of the binary combination of Ukrain with gemcitabine.

[0146] The dosages for a pharmaceutical product comprising the combination according to the invention can be obtained from the concentrations described in the examples; for this purpose, pharmaceutical products may be considered which include, in addition to the combination, also excipients for oral or injectable administration.

[0147] Such applications will still fall within the scope of the following claims.

[0148] Finally, for clarity's sake, all bibliographical references are listed below: [0149] [Biswas et al 2008] [0150] Biswas S J, Bhattacharjee N, Khuda-Bukhsh A R. (2008) Efficacy of a plant extract (Chelidonium majus L.) in combating induced hepatocarcinogenesis in mice. Food Chem Toxicol. 46(5):1474-87. [0151] [Capistrano et al. 2015] [0152] In vitro and in vivo investigations on the antitumour activity of Chelidonium majus. Capistrano I R, Wouters A, Lardon F, Gravekamp C, Apers S, Pieters L. Phytomedicine. 2015 Dec. 15; 22(14):1279-87. doi: 10.1016/j.phymed.2015.10.013. Epub 2015 Nov. 10. Work published after filing the patent application. [0153] [Chaadaeva et al. 2009] [0154] Chaadaeva A V, Tenkeeva I I, Moiseeva E V, Svirshchevskaia E V, Demushkin V P. (2009) Antitumor activity of the plant remedy peptide extract PE-PM in a new mouse T-lymphoma/eukemia model. Biomed Khim 55(1):81-8. [0155] [Chen et al. 2012] [0156] Chen C H, Liao C H, Chang Y L, Guh J H, Pan S L, Teng C M. Protopine, a novel microtubule-stabilizing agent, causes mitotic arrest and apoptotic cell death in human hormone-refractory prostate cancer cell lines. Cancer Lett. 2012 Feb. 1; 315(1):1-11. doi: 10.1016/j.canlet.2011.09.042. [0157] [Chou, 2006] [0158] Ting-Chao Chou, 2006: Theoretical Basis, Experimental Design, and Computerized Simulation of Synergism and Antagonism in Drug Combination Studies, Pharmacol Rev 58:621-681 [0159] [Chou, 2010] [0160] Ting-Chao Chou, 2010: Ting-Chao Chou 2010: Drug Combination Studies and Their Synergy Quantification Using the Chou-Talalay Method, Cancer Res. 70:440-446) [0161] [El-Readi et al 2013] [0162] Modulation of multidrug resistance in cancer cells by chelidonine and Chelidonium majus alkaloids. El-Readi M Z, Eid S, Ashour M L, Tahrani A, Wink M. (2013) Phytomedicine 20(3-4):282-94. [0163] [Fan et al. 2913] [0164] Fan L X, Liu C M, Gao A H, Zhou Y B, Li J. Berberine combined with 2-deoxy-d-glucose synergistically enhances cancer cell proliferation inhibition via energy depletion and unfolded protein response disruption. Biochim Biophys Acta. 2013 November; 1830(11):5175-83. doi: 10.1016/j.bbagen.2013.07.010. [0165] [Funel et al. 2010] [0166] Ukrain affects pancreas cancer cell phenotype in vitro by targeting MMP-9 and intra-/extracellular SPARC expression. Funel N, Costa F, Pettinari L, Taddeo A, Sala A, Chiriva-Internati M, Cobos E, Colombo G, Milzani A, Campani D, Dalle-Donne I, Gagliano N. (2010) Pancreatology 10(5):545-52. [0167] [Gagliano et al. 2012] [0168] Pancreatic cancer cells retain the epithelial-related phenotype and modify mitotic spindle microtubules after the administration of ukrain in vitro. Gagliano N, Volpari T, Clerici M, Pettinari L, Barajon I, Portinaro N, Colombo G, Milzani A, Dalle-Donne I, Martinelli C. Anticancer Drugs. 2012 October; 23(9):935-46. doi: 10.1097/CAD.0b013e32835507bc. 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[0174] [Habermehl et al. 2006] [0175] Proapoptotic activity of Ukrain is based on Chelidonium majus L. alkaloids and mediated via a mitochondrial death pathway. Habermehl D, Kammerer B, Handrick R, Eldh T, Gruber C, Cordes N, Daniel P T, Plasswilm L, Bamberg M, Belka C, Jendrossek V.BMC Cancer. 2006 Jan. 17; 6:14 [0176] [Jesionek et al. 2015 [0177] Investigation of the composition and antibacterial activity of Ukrain drug using liquid chromatography techniques. Jesionek W, Fornal E, Majer-Dziedzic B, Mricz M, Nowicky W, Choma I M., J Chromatogr A. 2016 Jan. 15; 1429, 340-347. doi: 10.1016/j.chroma.2015.12.015. Epub 2015 Dec. 8. [0178] [Kurochkin et al. 2000] [0179] Induction of apoptosis in cultured Chinese hamster ovary cells by Ukrain and its synergistic action with etoposide. Kurochkin S N, Kolobkov S L, Votrin I I, Voltchek I V. Drugs Exp Clin Res. 2000; 26(5-6):275-8. 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[0186] [Park et al. 2015] [0187] Chelidonium majus L. extract induces apoptosis through caspase activity via MAPK-independent NF-B signaling in human epidermoid carcinoma. A431 cells. Park S W, Kim S R, Kim Y, Lee J H, Woo H J, Yoon Y K, Kim Y I. (2015) Oncol Rep. 33(1):419-24. Epub 2014 Oct. 23 [0188] [Skivka et al. 2011] [0189] The effect of monotherapy and combined therapy with NSC-631570 (ukrain) on growth of low- and high-metastasizing B16 melanoma in mice. Skivka L, Susak Y, Trompak O, Kudryavets Y, Bezdeneznikh N, Semesiuk N, Lykhova O. J Oncol Pharm Pract. 2011 December; 17(4):339-49. doi: 10.1177/1078155210382470. Epub 2010 Sep. 3. [0190] [Staniszewski et al 1992] [0191] Staniszewski A, Slesak B, Kolodziej J, Harloziska-Szmyrka A, Nowicky J W. Lymphocyte subsets in patients with lung cancer treated with thiophosphoric acid alkaloid derivatives from Chelidonium majus L. (Ukrain). Drugs Exp Clin Res. 1992; 18 Suppl:63-7. 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