Reducing Damage From Chemotherapy And Increasing Cancer Kill Rates By Using Interweaved Low Dose Radiation

Abstract

The present invention provides a method of preventing damage to non-neoplastic cells i.e. healthy cells by irradiating with a low-dose radiation to the non-neoplastic cells, wherein the low-dose radiation is used to initiate a protective cellular response which prevents later damage to non-neoplastic cells by cytotoxic chemical agents or chemo agents and initiating an immune response against neoplastic cells. The low-dose radiation is applied to the sensitive and the non-cancerous organs/cells at a given time before a high dose chemo/drug infusion session.

Claims

1. A method of killing cancerous cells comprising: (a) administering a low dose radiation to neoplastic tissues, non-neoplastic cells surrounding neoplastic tissues and non-neoplastic cells sensitive to a chemo-drug; wherein said low dose radiation elicits antibodies against neoplastic tissues and elicits a repair mechanism in the non-neoplastic cells and in the non-neoplastic cells sensitive to the chemo-drug; and wherein said low dose radiation on neoplastic tissues causes anchors to form in the blood vessels within said neoplastic tissues that aids in latching of antibodies to anchors, allowing the antibodies to enter nearby neoplastic cells and kill them; (b) waiting for a period of 48 to 72 hours and infusing a chemotherapeutic drug to act upon said neoplastic tissues.

2. The method of claim 1, wherein irradiating the non-neoplastic cells modulates one or more genetic pathway responsible for cell repair proteins.

3. The method of claim 2, wherein the modulation of genetic pathway by low dose radiation on the non-neoplastic cell can be used to determine the reaction of one or more pharmaceuticals or chemical agents on said one or more non-neoplastic cell.

4. The method of claim 2, wherein the modulation of genetic pathway by low dose radiation on the non-neoplastic cell can be used to protect against radiation hazards (e.g. radiation workers, first responders, and astronauts).

5. The method of claim 1, wherein the low dose radiation is in range of 5 cGy to 20 cGy.

6. The method of claim 1, wherein the non-neoplastic cells are in contact with or in close proximity to a target neoplastic cell of a neoplastic disease.

7. The method of claim 1, which is a method of therapeutic treatment of cancer with chemotherapy.

8. The method of claim 1, wherein the low dose can be administered by a neutron beam as well as a standard x-ray/gamma beam.

9. A method for killing cancerous cells comprising: (a) targeting a tumor tissue, tissues sensitive to a chemo drug and one or more non-neoplastic cells present in vicinity of a tumor tissue with a predetermined low dose of radiation, wherein said low dose radiation induces an immune response against tumor tissues, a cellular repair process in said one or more non-neoplastic cell and tissues sensitive to the chemo drug; wherein the low dose radiation on the tumor tissue causes anchors to form in the blood vessels within said tumor tissue that aids in latching of antibodies to anchors, allowing the antibodies to enter nearby tumor cells and kill them; (b) waiting for a period of 48 to 72 hours and infusing a chemotherapeutic drug to act upon the tumor tissue; and wherein the above steps are repeated till the recommended dose of high radiation is completed.

10. The method of claim 9, wherein low dose of radiation modulates one or more genetic pathway of non-neoplastic cells to induce cell repair proteins.

11. The method of claim 9, wherein the low dose radiation is in range of 5 cGy to 20 cGy.

12. The method of claim 9, wherein the immune response initiated by the low dose radiation inhibits the proliferation of neoplastic cells.

13. The method of claim 9, wherein the immune response protects the healthy non-neoplastic cells and tissues sensitive to the chemo drug from the chemo drug.

14. A method of killing cancerous cells comprising: (a) administering a low dose radiation to neoplastic tissues, non-neoplastic cells surrounding neoplastic tissues and non-neoplastic cells sensitive to a chemo-drug; wherein said low dose radiation elicits antibodies against neoplastic tissues and elicits a repair mechanism in the non-neoplastic cells and in the non-neoplastic cells sensitive to the chemo-drug; and wherein said low dose radiation on neoplastic tissues causes anchors to form in the blood vessels within said neoplastic tissues that aids in latching of antibodies to anchors, allowing the antibodies to enter nearby neoplastic cells and kill them; (b) waiting for a period of 48 to 72 hours and administering a second predetermined low dose radiation to the non-neoplastic cells surrounding neoplastic tissues and non-neoplastic cells sensitive to the chemo-drug, wherein said second predetermined low dose radiation elicit repair mechanism in said non-neoplastic cells; (c) waiting for 24 hours and infusing a chemotherapeutic drug to act upon said neoplastic tissues.

15. The method of claim 14, wherein the low dose radiation is in range of 5 cGy to 15 cGy.

16. The method of claim 14, wherein the low dose radiation modulates the genes responsible for repair mechanism in the non-neoplastic cells.

17. The method of claim 14, wherein antibodies against neoplastic tissues prevent invading neoplastic cells from entering into non-neoplastic cells.

18. The method of claim 14, wherein the repair mechanism in non-neoplastic cells protects the cells from the chemo drugs.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG. 1 is a table of the effects of radiation dosages in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0022] In the following detailed description of embodiments of the invention, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the invention. However, it will be obvious to a person skilled in the art that the embodiments of the invention may be practiced with or without these specific details. In other instances, well known methods, procedures and components have not been described in details so as not to unnecessarily obscure aspects of the embodiments of the invention.

[0023] Furthermore, it will be clear that the invention is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions and equivalents will be apparent to those skilled in the art, without parting from the spirit and scope of the invention.

[0024] As used herein, the terms neoplastic, cancer, and tumor are used interchangeably to indicate a cell, tissue, or condition in which there is uncontrolled or abnormally fast growth of one or more cells of a particular type. The invention is applicable to neoplastic cells of cancer or tumor in all of its forms. Such growth can happen in vivo to produce a mass of cells within an organism, such as a human, or can occur in vitro to produce a culture of cells that might or might not have characteristics of cell lines. Accordingly, such cells or tissues can be, but are not necessarily, immortal such as stem cells. Likewise, the cells or tissues can be, but are not necessarily, primary cells obtained directly from a cancerous or a non-cancerous tissue.

[0025] As used herein, the term sensitive cells, sensitive tissues, and sensitive organs imply the non-neoplastic cells or tissues or organs on which a particular chemo drug or agent has an adverse effect, thus hampering their normal activity.

[0026] Furthermore, as used herein, the terms radiation (and all of its forms) and electromagnetic energy are used interchangeably to indicate energy of one or more wavelengths of the electromagnetic spectrum. The invention is not limited to the use of a particular wavelength, but instead can be used with any wavelength of the electromagnetic spectrum. For example, the invention contemplates use of a particular wavelength of energy that can activate a substance that can absorb one wavelength of energy and re-emit at another wavelength. For ease of reference, electromagnetic energy is typically referred to herein as radiation, and this term is to be broadly interpreted.

[0027] More specifically, radiation is energy that comes from a source and travels through some material or through space. Thus, light, heat, and sound are types of radiation. One useful type of radiation according to the present invention is ionizing radiation, which is radiation that can produce charged particles (i.e., ions) in matter. Ionizing radiation is often produced in the medical setting by man-made devices, such as CT-Scan, X-ray, or Linear Accelerator Machines (LINAC). It is well known that ionizing radiation can be produced by unstable atoms (i.e., radioactive atoms), which are atoms that have an excess of energy, mass, or both, and which shed or emit that energy and/or mass in the form of radiations in order to achieve a stable state. For the purposes of this invention, it is to be understood that there are two kinds of radiation: electromagnetic (e.g., light, gamma radiation, X-rays, ultraviolet) and particulate (e.g., proton or neutron emission, beta and alpha radiation).

[0028] Furthermore, as used herein, the terms chemotherapy agent (and all of its forms), chemo agent, chemo drug and chemical agents are used interchangeably.

[0029] It is also to be understood that, where the invention relates to therapeutic treatment of a subject, a diagnosis of a localized cancer has been made and the size, shape, and location of the cancerous mass has been determined by standard methods known in the art. In other words, it is to be understood that the invention relates to in vivo of a patient in need thereof, and the routine procedures for identifying such patients and characterizing their tumor(s) have been performed. By subject, it is meant any living organism in which a neoplasia may exist. Thus, a subject may be, but is not limited to, a human or other animal (e.g., a dog, cat, horse, bird, or other companion or agricultural animal). As used herein, the terms subject, patient, person, and animal, unless otherwise indicated, are used interchangeably to indicate a living organism in which a neoplasm may exist. Accordingly, the present invention has application in both the human health field and in veterinary medicine.

[0030] The present invention discloses a method for protecting normal healthy cells and sensitive organs from chemotherapy and chemical agents. The method provides prevention from damage to non-neoplastic i.e. healthy cells, which occurs during standard chemotherapy sessions. For this purpose, low-dose radiation is used to initiate a protective cellular response which prevents or reduces damage to non-neoplastic cells by cytotoxic chemical agents. After pre-dosing a healthy cell with a low dose radiation, the cell responds by modulating genes that produce repair proteins that control certain cell functions, which include creating immune response among others. These proteins then proceed to repair the damage to the cell, a process that lasts for days. The present invention also discloses a method of preventing damage to non-neoplastic cells, wherein the low-dose radiation is applied to sensitive tissues and organs before the chemo drug infusion session.

[0031] In an embodiment, the present invention also provides a method for eliciting an immune response against cancerous cells. When a low dose radiation is applied to healthy cells and neoplastic cells, it generates an immune response in the body against cancerous cells by generating antibodies against them. When the neoplastic or tumor cells are exposed to low dose radiation, it helps them to form anchors on the blood vessels, the antibodies latches on to these anchors, exit from blood vessels and kill the invading cancerous cells that tried to escape into the healthy cells.

[0032] The invention relates to in vivo and in vitro treatment of cells. In aspects relating to in vivo uses, it is generally a method of therapeutic treatment, which can be curative or prophylactic. Thus, the method can be practiced on a subject suffering from a neoplastic disease, such as the one in which a neoplastic mass is growing, to reduce the growth of, reduce the size of, or eliminate the neoplastic mass. In addition, the method can be practiced on a subject who previously suffered from a neoplastic disease, such as the one who had a neoplastic mass removed by surgery or radiation treatment, to ensure that all neoplastic cells of the mass are killed. The present invention provides particular protocols for pre-dosing healthy cells and tissues, especially those that are very sensitive to the chemotherapy substance, with low-dose radiation, while avoiding irradiating cancerous cells, in order to induce a cellular repair response in the healthy cells/tissues. This is then followed by any standard chemotherapy protocol therapy.

[0033] As a general matter, the method described herein relates to pre-treating healthy tissues that are at risk from standard chemotherapy agents, including those surrounding the neoplastic growth and other organ tissues sensitive to the chemotherapy agents, with a low-dose radiation. This low dose radiation exposure results in an adaptive response in the irradiated cells and tissues that increases the probability of survival of healthy tissue upon various insults such as those arising from subsequent cancer therapy. The neoplastic tissues are also exposed to low dose radiation, which initiates an immune response against the cancerous cells by causing anchors to form in the blood vessels within said cancerous cells. The antibodies latches to the anchors and thus allows the antibodies to enter nearby cancerous cells and kill them. The immune response starts as early as 1 hour of exposure to low dose radiation and remains active for few days up to 72 hours.

[0034] During a subsequent chemotherapy protocol designed to kill the cancerous cells, the healthy cells and sensitive organs which may include but are not limited to heart, intestine, bone marrow, hair follicles, kidneys and other chemo-agent sensitive tissues in the body will inevitably be damaged as well. Also, tissues that are not in the vicinity of the cancerous tissue but are very sensitive to the chemotherapy agent can also be damaged. The pre-dose of radiation to the healthy cells and sensitive organs and tissues insures a much higher probability of their long term survival, and thereby reduces these adverse events.

[0035] For the low-dose radiation applied in the range of 0.05 Gy to 0.15 Gy, a cell initiates a repair sequence where many genes are modulated. The genes that produce repair proteins are turned on; the relevant proteins are then produced for a period of time. The production is known to start after about 6 hours and lasts upto few days. As these proteins are produced and move throughout the cell, they start repairing damage. Since this active repair period lasts for days, if the cell is then damaged again during this time, for example by a standard chemotherapy treatment, the repair commences immediately and at near full strength.

[0036] If a properly chosen low-dose of radiation, under aspects of the present invention, has been applied to a cell, its repair genes are modulated. Some are turned on to produce proteins that affect the repair. Other genes are turned off. This latter action can conserve energy needed for the repair and can also increase the time to the next scheduled mitosis (cell division). This gives more time to affect repairs before the errors can be passed on to the next generation.

[0037] Standard chemotherapy protocol requires administration of a selected cytotoxic chemical agent or chemo agent into the patient in a number of separated sessions, perhaps a few days apart. Under aspects of the present invention, each of these sessions involves exposure of a low dose radiation in the range of 0.05 to 0.15 Gy to the healthy sensitive cells and tissues followed by the chemo infusion process after 48 to 72 hours of the low dose radiation exposure to sensitive cells and tissues. During this time period, immune response induced in the patient body acts on the cancerous cells and also prevents establishment of neoplastic cells in adjacent healthy tissues. The time spacing between the radiotherapy exposure and the chemo-agent infusion is chosen to maximize the efficacy of the adaptive response in repairing damage suffered by healthy cells.

[0038] The invention provides particular protocols for pre-dosing healthy cells and tissues with low-dose radiation, while avoiding irradiating cancerous cells, in order to induce a cellular repair response in the healthy cells/tissues, followed by a chemotherapy protocol. In embodiments, it has been found that a pre-dose as small as 1 mGy (in Gray Units) can induce a protective cellular adaptive response. For better understanding of the physical mechanisms arising from a radiation dose, note that a dose of one mGy corresponds roughly to one radiation track per cell. The average radiation exposure from natural sources is 3 mGy/yr and from human activity 1 mGy/yr. The total radiation dose from a chest CT scan or an abdominal CT scan is approximately ˜110 mGy=1 cGy.

[0039] In embodiments, the strategy is to select and use those chemo agents which can be effectively stopped by the adaptive repair processes triggered by a pre-dose of low-dose radiation. Such selection offers the optimum protection for the healthy cells after exposure to a pre-dose of low-dose radiation. After pre-dosing a healthy cell with low-dose radiation, the cell responds by modulating genes that produce repair proteins and that control certain cell functions, and initiate immune response. These proteins then proceed to repair the damage to the cell, a process that lasts for several days. Certain processes that are a drain on the cell are slowed down so that the repair can proceed as rapidly as possible, optimally completed before the next cell division. This slowing of cellular reproduction is also a benefit of the pre-dosing regimen because chemotherapeutic agents affect rapidly dividing cells.

[0040] In chemotherapy, a chemical agent is chosen that attacks, damages, and eventually kills rapidly reproducing cells. The cell lifecycle is conventionally divided into 5 phases. Each chemotherapeutic agent will attack a rapidly growing cell during one of the phases. In accordance with the embodiments, chemotherapy is normally applied in defined time cycles, for example, once a week or once every three weeks, as prescribed by the oncologist. Furthermore, the day of chemotherapy application is often preceded one day earlier by a pre-treatment medication and the day after by a blood count booster treatment. These are used to help the patient recover from the side effects of the therapy. To restate the main idea of this therapy, the targeted low-dose radiation therapy offers protection to the healthy cells of the body while denying that same protection to cancerous cells. The immune response acts on the cancerous cells and also prevents the escape of neoplastic cells to adjoining healthy tissues.

[0041] In a situation where a localized tumor is in the interior of the body, within or at the surface of an organ, a low radiation dose is applied to the cells surrounding the tumor in the organ prior to the injection of the chemotherapy agent. If there are remote organs or cells that are particularly sensitive to the specific chemo-agent used, then they are also provided with low-dose protective irradiation. The adaptive response of the cell to a low-dose of radiation is in the range of 0.01-0.4 Gy that causes the modulation of many genes, including those that are involved in DNA-RNA repair. Other modulated repair genes include cell-cycle control, heat shock, ion regulation and membrane repair. Still others involve myelin and protein synthesis repair and an immune system response. These up-regulated genes produce their repair proteins over a period of hours and these proteins persist for at least two days. Once the cells are protected, and prior to the expiration of the repair proteins, most preferably when repair protein levels are at peak amounts, or preferably when they have not degraded to baseline levels present at pre-radiation time, a selected chemotherapy agent is injected whose main modes of cell killing can be counteracted by the repair gene proteins produced by the adaptive response. The cancer cells, that did not receive the low radiation dose and are hence unprotected, are killed by the chemo agent as usual, whereas the low radiation dosed cells are able to recover from the chemotherapeutic damage, most preferably prior to cell division.

[0042] Furthermore, many cell types in the body are very sensitive to damage at sufficiently high doses of chemotherapeutics. Among these are bone marrow, mucosal cells of the intestinal tract, liver and kidney cells, epithelial cells and nervous system cells. It is thus possible to protect these cells by applying a low-dose radiation to turn on their repair mechanisms and these cells are especially suited to usage of the protocols specified herein, e.g. a low pre-dose of radiation in the range of 0.01-0.4 Gy.

[0043] As discussed above, preferred chemotherapeutic agents are those which affect cell cycle stages that are susceptible to the cellular repair proteins produced after an exposure to low level of radiation and may be selected from the classes of alkylating agents, anti-metabolite agents, and topoisomerase agents: The alkylating class of chemotherapeutic agents (originally derived from mustard gas) bind covalently to the DNA, RNA and to some protein molecules. This prevents normal mitosis, thereby inducing apoptosis (death) of the cell. The repair proteins present in the cell after the low-dose treatment work to return the affected (alkylated) DNA, RNA and protein molecules to their normal state. The anti-metabolite class of chemotherapeutic agents operates by impeding the synthesis of DNA and RNA by incorporating themselves into their structure. The repair proteins produced by low-dose radiation restore the DNA and the RNA to their normal state. The topoisomerase class of inhibitors operates by not allowing the DNA to stretch and unwind during replication or transcription. The repair proteins produced by low-dose radiation restore the equilibrium situation of the DNA, allowing normal replication of the cells.

[0044] In embodiments, a protocol is used that does not disrupt the normal chemotherapeutic schedule. For example, the day of chemo application is often preceded a few days earlier by a pre-treatment and the day after by another booster treatment. These are used to help the patient recover from the side effects of the therapy. Therefore, the day before the chemo application could also be used for a low-dose radiation session.

[0045] In embodiments one or more chemotherapeutic agents may be used in combination or series according to their standard protocols of prescription, with low-dose irradiation as described herein being applied to the non-cancerous tissues. In embodiments the noncancerous tissues may be selected from those most susceptible to the selected chemotherapeutic(s) or those tissues that are most likely to be the targets of migrating cancer cells. In other embodiments, the low-dose irradiation as described herein may be applied to the whole body, excepting the tumor tissue. In further embodiments, non-neoplastic cells which would suffer non-killing damage are protected from such damage by the above methods.

[0046] The low-dose radiation is applied to the healthy cells present in the patient's body that are at risk from the chemotherapy agent, as the chemotherapy treatment is systemic. Then after a selected wait period, a standard chemotherapy treatment is applied. The low-dose radiation may be applied prior to each session of a chemotherapy treatment regimen. Since the healthy cells inevitably receive a toxic chemical exposure during chemotherapy sessions, they now have the extra protection of the adaptive response initiated by the low-dose radiation applied prior to the chemotherapy. The beneficial effect of low dose radiation on the healthy cells for inducing protecting response in them is studied in the research article, entitled “Beneficial effects of low dose radiation in response to the oncogenic KRAS induced cellular transformation” by Kim et al.

[0047] In another embodiment of the present invention, a method to kill cancer cell is provided. The method comprising administering low dose radiation to neoplastic tissues, non-neoplastic cells surrounding neoplastic tissues and non-neoplastic cells sensitive to a chemo-drug; wherein said low dose radiation elicits antibodies against neoplastic tissues and elicits a repair mechanism in the non-neoplastic cells and in the non-neoplastic cells sensitive to the chemo-drug; and wherein said low dose radiation on neoplastic tissues causes anchors to form in the blood vessels within said neoplastic tissues that aids in latching of antibodies to anchors, allowing the antibodies to enter nearby neoplastic cells and kill them; (b) waiting for a period of 48 to 72 hours and infusing a chemotherapeutic drug to act upon said neoplastic tissues. The administration of low dose radiation to neoplastic tissues elicits an immune response in the neoplastic tissues which helps in killing the cancerous cells.

Example 1

[0048] As an example, in our most recent experimentation, human subjects with epithelial skin cells were treated in-vivo with two methodologies. The first patient received an interweaving low dose radiation of 10 cGY, specifically to the healthy tissue surrounding the localized skin cancer. The second patient also received low dose radiation of 10 cGy to both the neoplastic cells and healthy cells adjacent to the tumor. Both patients underwent biopsies before treatment, 24 hours after the low dose treatment, and then one week later after standard therapy.

[0049] The protocols were tested in-vivo, with DNA analysis verifying the effect of low dose radiation: a) the excitement of a cellular repair adaptive and immune response in healthy tissue surrounding the neoplastic cells. b) the excitement of a cellular repair adaptive response in neoplastic cells that is outweighed by the immune response in the neoplastic cells that increases cancer kill rates by upto 5 fold. To clarify, the low dose radiation elicits antibodies against neoplastic tissues and elicits repair mechanisms in non-neoplastic cells and cells sensitive to the chemo-drug; and wherein said low dose radiation on neoplastic tissues causes anchors to form on said neoplastic tissues that aids in latching of antibodies onto said neoplastic tissues.

[0050] Schedules for Radiation-Chemo Sessions

[0051] To induce protective adaptive response in non-cancerous sensitive tissue and organs, and to utilize the protective adaptive response for scheduling chemotherapy session for a patient, the present method targets the organs that are sensitive to a particular chemo-agent with a predetermined low dose radiation. The method may also involve targeting the non-neoplastic cells that may or may not be in contact with or in close proximity to the target neoplastic cell with the predetermined low dose radiation. The low dose radiation induces a cellular repair process in the targeted chemo-agent sensitive organs and the non-neoplastic cell. Many genes are modulated. Each of the modulated repair genes can initiate a complicated pathway that involves the excitation of many other subsequent genes. The study of these pathways serves an important role in the development of chemotherapy and other drug agents for treating tumorous and cancerous tissues. The use of low dose radiation to excite these pathways can have many advantages over chemical excitation.

[0052] In an embodiment of the present invention, a method for treating at least one neoplastic cell with a harmful amount of electromagnetic energy is provided. The method involves the induction of adaptive response in healthy cells surrounding the tumor mass so that they may be able to withstand the harmful effect of subsequent high dose exposure of radiation. The method also involves initiating an immune response in the body. It has been found during the experiment that a low dose exposure to cancerous cells and healthy cells initiate an immune response in the body against cancerous cells.

[0053] The method for treating at least one neoplastic cell comprises: a) administering a low dose radiation to neoplastic tissues and non-neoplastic cells surrounding neoplastic cells within 0.1 to 3.0 cm of a tumor; wherein said low dose radiation elicits repair mechanism in the non-neoplastic cells and antibodies against neoplastic tissues; and wherein said low dose radiation on neoplastic tissues causes anchors to form on said neoplastic tissues that aids in latching of antibodies on to said neoplastic tissues; (b) waiting for a period of 48 to 72 hours and administering a high dose radiation to neoplastic tissues. During this time period, immune response induced in the patient body acts on the cancerous cells and also prevents establishment of neoplastic cells in adjacent healthy tissues. The time spacing between the radiotherapy exposure and the high dose radiation application is chosen to maximize the efficacy of the adaptive response in repairing damage suffered by healthy cells.

[0054] The low dose radiation on the healthy cells modulates repair protein genes in the cell to induce protective adaptive response in non-cancerous tissue. The method utilizes this protective adaptive response of cell for modifying the radiation therapy dosage schedule. The pre-dose of the healthy cells with low dose radiation insures a much higher probability of their long term survival, and thereby reduces the adverse events associated with radiation therapy. The effect of radiation on a cell depends on the type of cell and the amount of radiation and its dose rate. For example, a muscle cell, a liver cell, and a breast cell, etc., react to radiation in different ways and the scale of the reaction depends on the radiation beam parameters. In choosing the specifics of the optimum low-dose radiation beam for treatment, these radiation beam parameters are chosen corresponding to the cell type being irradiated.

[0055] After pre-dosing a healthy cell with a low dose radiation, the cell responds by modulating genes that produce repair proteins that control certain cell functions, which include creating immune response among others. These proteins then proceed to repair the damage to the cell, a process that lasts for days. The low dose radiation induces metabolic changes in the non-neoplastic cells and modulates the repair protein genes responsible for cell repair mechanism. As these proteins are produced and moved throughout the cell, they start repairing the damage. The protein producing genes remain activated for a period of time, up to several days; therefore the relevant protein is being produced and keeps on repairing the damaged cells for that time period. Since, the active repair period lasts for days, if the cell is then damaged again during this time, for example by standard high-dose radiotherapy, the repair commences immediately and at near full strength.

[0056] Exposure with low dose radiation also turns off other genes; this action conserves energy needed for the repair and also increases the time for the next scheduled mitosis (cell division). This gives more time to affect repairs before the errors can be passed on to the next generation.

[0057] Table 1 represents some of the genes that are known to respond to the low dose radiation:

TABLE-US-00001 TABLE 1 Number Responsive Group of Genes Genes Function I 11 MBD4, OGG1 Base excision repair (BER) II 6 APEX1, LIG3, Other BER and strand break PNKP joining factors III 3 PARP1, PARP2 Poly(ADP-ribose) polymerase (PARP) enzymes IV 3 MGMT Direct reversal of damage V 2 TDP1 Repair of DNA-topoisomerase crosslinks VI 10 MSH2 Mismatch excision repair (MMR) VII 24 XPC, DDB2, Nucleotide excision repair (NER) LIG1

[0058] The exposure of low dose radiation on neoplastic cells or tumor cells have effects, such as initiation of immune response in the body. The immune system usually recognize cancer cells and “killer T cells” invade the tumor tissues. Normally immune cells migrate into tissues through “anchors” formed by blood vessels. As the invading immune cells flow through blood stream, they latch onto the anchors and can thus leave the bloodstream. The problem with tumors is that they often prevent the anchors from forming, which prevents the killer T cells from using these exit points. The exposure of cancerous cell to low dose radiation leads to the formation of anchor molecules in the vessel wall. Additionally, the low dose exposure to healthy cells and cancerous cells results in generation of antibodies against tumor cells that lasts for several days. A low dose radiation, striking as far away as 1.5 cm from the surface of a tumor, will excite an immune response not only in healthy tissues but also in nearby tumor cells. Due to the excitation of immune response, the growth of these tumor cells is then reduced. The immune response generated by the low dose radiation has an additional benefit, in that it prevents the cells from the tumor mass to invade the surrounding healthy tissues.

[0059] The main pathways of the immune response triggered by the low dose radiation includes, but are not limited to: a) Altered T cells and B Cell Signaling; b) Antigen presentation pathway; c) B cell development; d) OX40 Signaling Pathway. These pathways result in the production of molecules associated with Dendritic cell maturation, NF-kB signaling, and Fcy receptor-mediated Phagocytosis in macrophages and monocytes.

[0060] It was found that this immune response is active within 24 hours of the exposure, whereas a natural trigger normally requires 6-8 days to become fully active. This quick response could be a very important feature in the application of low dose radiation. The low dose turns on the natural immune response as well as the induced adaptive response.

[0061] Another effect of low dose radiation is the activation of immune response, which acts on the cancerous tissue and also prevents escape of neoplastic cells to the surrounding healthy tissues. After waiting for 48 to 72 hours, the chemotherapy agent can then be administered to the patient.

[0062] In an embodiment of the present invention, the low dose radiation is in the range of 5 cGy to 15 cGy, wherein the low dose may be administered by a neutron beam or as well by a standard x or gamma-ray beam. In an embodiment of the present invention, the time period between the low dose radiation and administration of a chemotherapy dose, which can be termed as the wait time is between 6 and 48 hours.

[0063] Chemotherapy drugs are administered in many ways: orally, injection into different regions of the body, implantable wafers, and topically in the protective time window.

[0064] A low dose radiation will cause an adaptive response that turns on certain repair genes. These genes then produce a set of proteins that proceed to repair the damages to the cell. The production of these proteins starts a few hours after exposure and then proceeds for few days after irradiation with the low dose radiation. This time period is the protective window offered to irradiate sensitive cells and tissue by the low dose radiations.

[0065] Chemotherapy is usually given in cycles with rest periods between two sessions, so as to allow the patient to recover from the effect of the treatment and to allow the cancer or tumor cells to be attacked at their most vulnerable times. Normally a premedication is given to reduce the worst side effects. The infusion sessions can be scheduled for several consecutive days, weekly or even longer periods.

[0066] In an embodiment of the present invention, various possible schedules for combination of low dose radiation and chemo sessions are provided that uses the time dependence of the adaptive response generated in the irradiated sensitive cells and tissues (protective window). Practical schedules of the standard chemotherapy sessions are restricted by the standard work week and work rules.

[0067] There can be various possible schedules such as:

[0068] Once a Week:

[0069] In an exemplary embodiment, when the oncologist has determined the chemotherapy session has to be administered to patient is once a week, then the patient is administered with the determined chemo drug in the protective window period. In this case, prior to administration of the chemo drug or agent, the tissue and organs of the patient sensitive to that particular chemo drug or agent and tumor tissue is irradiated with the low dose radiation so as to modulate the protective adaptive response in the sensitive tissues and organs. Then after a wait time of approximately 48 to 72 hours, the patient is administered with the chemo drug or agent. The administration of chemo drug or agent to the patient is done within the protective time window.

[0070] Three Consecutive Days:

[0071] In another exemplary embodiment, if the chemotherapy session as determined by an oncologist for the patient is three consecutive days, then according to the embodiments of the present invention, the session can be scheduled as follows: firstly exposure of low dose radiation is given to sensitive cells and tissues of the patient and neoplastic tissues, then waiting for 48 to 72 hours, and then performing first dose of chemo drug infusion. Then after a wait period of 24 hours, second dose of chemo drug is administered and then after a wait time of 24 hours, third dose of chemo drug is administered to the patient.

[0072] In an embodiment of the present invention, the patient can be irradiated with multiple low dose radiation sessions in a week, depending on the intensity of the chemo treatment.

[0073] In another embodiment of the present invention, a method for interweaving one or more low dose radiation session with one or more chemotherapy sessions is provided to prevent the harmful effects of chemo drugs on to healthy sensitive cells of the human body. According to the method one or more non-neoplastic cells or tissues or organs, that may not be in the vicinity of the cancerous cells but are particularly sensitive to the particular chemotherapy agent, and the neoplastic tissues are targeted with a predetermined low dose radiation. The low dose radiation induces a cellular repair process in said one or more non-neoplastic cells or tissues or organs and immune response in neoplastic tissues. The repair process remains active during a protective window period. Then a wait period of 48 to 72 hours is allowed to pass. Following the wait period, varying levels of the chemotherapy agents are administered to the patient till the protective window period is over. If the dose of the chemo agent has not been completed and the protective window period is over, then before administering another dose of chemo agent, the sensitive cells or tissues or organs are again irradiated with a low dose radiation. The next remaining dose of chemotherapy agents or drugs is then administered to the patient in the protective window period of second low dose radiation. This process is repeated till the complete scheduled dose of chemo drug has been administered to the patient.

[0074] There are many other possible schedules that interweave the low dose radiation session with the chemo infusion sessions and still make full use of its protective properties.

[0075] In this way, the present invention provides a therapeutic treatment of cancer with chemotherapy preceded by a low dose radiation exposure. To clarify, if a low dose radiation is applied to both the tumor and the surrounding healthy cells, then the repair genes in both cell types will be activated. However if the immune response in the cancer cells is stronger than its repair mechanism, then the cancer cells will undergo a net negative effect. Preliminary results on human cells have indicated that the immune response is several times (up to 5 times) stronger than the repair response. Following the low dose exposure, a standard chemotherapy procedure is applied.

[0076] In an embodiment of the present invention, the method of using low dose radiation to induce a protective adaptive response in the cells or tissues or organs sensitive to a chemotherapy agents or drugs can be used to increase the number of chemo drugs that can be used in therapy. Different chemo drugs have different efficiencies in killing cancerous or tumor cells. Some are extremely efficient in killing cancerous cells, but due to their lethal effect on healthy cells, the clinical use of these drugs is very restricted. The method of the present invention can be used to devise a strategy for using these chemo drugs. In an embodiment, the method comprises: identifying a chemo drug that is effective against cancerous cells; identifying one or more healthy cells or tissues that are sensitive to the chemo drug; irradiating the one or more sensitive cells or tissues with a low dose radiation; then administering the chemo drug to the patient during the protective window of the low dose radiation to optimize the cancer kill rates while sparing the patient from the lethal effects of the chemo drug on healthy tissue or cells.

[0077] Consider a chemo drug that is extremely effective in killing cancerous cells but is also quite lethal to certain healthy cells. If the application of low dose radiation activates repair genes that are able to sufficiently repair damage caused by the chemo agent, then this agent can be used to treat patients following a low dose exposure. For example, cancer chemotherapy drugs such as anthracycline antibiotics are used to treat many types of cancers, but their main adverse effect is cardiotoxicity. This is disclosed in research article “Cardiovascular toxicity induced by chemotherapy, targeted agents and radiotherapy: ESMO Clinical Practice Guidelines. Annuals of Oncology Oct;23 Suppl 7, vii155-66”. For the use of anthracycline antibiotic for treatment of cancer, the present method can be used by exposing the cardiac cells to low dose radiation sufficient to induce an adaptive response. Thereafter, in the protective time window, the anthracycline antibiotics can be used to treat cancer cells without inducing serious cardiotoxicity.

[0078] In another embodiment of the present invention, the invention can be used on a patient with a tumor as well as on post-op patients whose tumor has been removed after a surgery. In a patient where a surgical procedure has removed or debulked a tumor, the chemotherapy process is generally employed to kill any tumor debris left over after the procedure. Before administering the chemo drugs, the sensitive cells and tissues are exposed to low dose radiation for inducing the protective adaptive response in these cells.

[0079] In another embodiment of the present invention, the method of killing cancerous cells comprises of: (a) administering a low dose radiation to neoplastic tissues and non-neoplastic cells surrounding neoplastic cells and cells sensitive to a chemo-drug; wherein said low dose radiation elicits antibodies against neoplastic tissues and elicits a repair mechanism in the non-neoplastic cells and in non-neoplastic cells sensitive to the chemo-drug; and wherein said low dose radiation on neoplastic tissues causes anchors to form in the blood vessels within said neoplastic tissues that aids in latching of antibodies to anchors, allowing the antibodies to enter nearby neoplastic tissues thus killing them; (b) waiting for a period of 48 to 72 hours and infusing a chemotherapeutic drug to act upon the said neoplastic tissues.

[0080] In other embodiments, the application of low dose radiation can also be used to excite an immediate immune response in the body, more quickly and efficiently than the body's typical immune response to cancer cells (24-48 hours vs. approximately six days). The irradiation of healthy body cells induces DNA damage in the cell which alerts the immune system by signals displayed on the cell surface. This effect has a strong link to the innate immune system and tumor surveillance. The activation of the immune response is an important tool in the study of the effects of low dose radiation and its effects on cancer. The immune response will combat local inflammation and also retard the growth of the cancer by attacking cancer cells located near or in the irradiated tissues as well as throughout the body. Due to induction of the immune response by the low dose radiation, an adaptive response throughout the entire body is produced and adverse effect of subsequent treatment with the chemotherapy agent on the healthy cells and tissues is prevented.

[0081] In another embodiment, the method of present invention can be used in similar possible sequences. For instance, the method comprises administering low dose radiation to health cells (non-neoplastic cells) that are adjacent to tumor tissue or are distantly located which are sensitive to a particular drug and to the neoplastic tissue. The low dose radiation on healthy cells elicit adaptive protective response and on tumor tissues, it elicits an immune response. Then a wait period of 48 to 72 hours is observed, during which antibodies can act on the tumor tissue. Thereafter, a low dose radiation is again administered to the healthy non-neoplastic cells, so that the adaptive response in them is triggered. After a wait period of 24 hours, chemotherapy agents are infused in the body to act upon remaining cancerous cells. The present invention envision another possible schedules for interweaving low dose radiation on non-neoplastic cells and neoplastic cells with chemo-drug infusion.

[0082] It will be apparent to those skilled in the art that other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention. While the foregoing written description of the invention enables one of ordinary skill to make and use what is considered presently to be the best mode thereof, those of ordinary skill will understand and appreciate the existence of variations, combinations, and equivalents of the specific embodiment, method, and examples herein. The invention should therefore not be limited by the above described embodiment, method, and examples, but by all embodiments and methods within the scope and spirit of the invention. It is intended that the specification and examples be considered as exemplary, within the true scope and spirit of the invention being indicated by the claims.