Sensitizer for tumor radiotherapy and application

Abstract

The invention relates to the technical field of biological medicine, in particular to a sensitizer for tumor radiotherapy and application. The sensitizer includes a hydrate of a cobalt-containing polyoxometallate. The sensitizer for tumor radiotherapy comprises the hydrate of cobalt-containing polyoxometallate, and the cobalt-containing polyoxometallate can be metabolized in vivo, has no side effect and is high in cost performance. Other high-atomic-number metals (such as tungsten) in the cobalt-containing polyoxometallate can enhance the radiation dose of local tumors, and cobalt metal can be released from the sensitizer through X-rays to induce pyroptosis of hypoxic tumor cells, so that the sensitivity of hypoxic irradiation tolerant tumor cells to radiotherapy is improved.

Description

Technical Field

[0001] The present invention relates to the field of biomedical technology, and in particular to a sensitizer for tumor radiotherapy and its application. Background Art

[0002] The incidence of malignant tumors is increasing year by year around the world, posing a serious threat to human survival and health. Radiotherapy is a treatment method that uses radiation or radioactive substances to treat cancer and other diseases. However, due to the common hypoxic environment inside solid tumors, hypoxic tumor cells develop resistance to radiotherapy, which means that the effectiveness of radiotherapy for patients is reduced and the subsequent increase in radiation dose leads to poor prognosis.

[0003] In view of the strong radioresistance of tumor cells, radiosensitizers are usually used to improve the effectiveness of radiotherapy. The commonly used radiosensitizers are irisin, sodium glycidazole and NBTXR3, and these drugs have significant disadvantages. For example, irisin and sodium glycidazole are both administered intravenously or orally, which reduces the efficiency of drug use, and both have significant toxic side effects on the body. At the same time, they need to be taken during radiotherapy, which further increases the harm to the patient's body; and the hafnium oxide in NBTXR3 cannot be metabolized and degraded in the body, and tumor cells cannot be targeted. It is also toxic to normal cells, and the price of NBTXR3 is relatively high. Recent studies have revealed the effects of various metal ions on cell death, including ferroptosis (Fe 2+ ), copper death (Cu + ), cGAS-STING signaling (Zn 2+ , Mn 2+ ), indicating that the radiation tolerance of tumors may be changed through metal-mediated pathways. Among them, cell pyroptosis as a new mechanism of cell death has attracted increasing attention. Pyroptosis is a programmed cell death mode in which cells continue to swell until the cell membrane ruptures, resulting in the release of cell contents. It mainly depends on the activation of gasdermin protein by inflammatory caspases. Due to the high expression of gasdermin C protein in hypoxic conditions, inducing hypoxic cells to undergo gasdermin C-mediated pyroptosis is a possible solution to improve the radiotherapy sensitivity of radiation-tolerant cells. Summary of the invention

[0004] The present invention provides a sensitizer for tumor radiotherapy and its application, which is used to solve the problems of low efficiency, large toxic side effects, high price and the like of existing sensitizers for tumor radiotherapy. The sensitizer for tumor radiotherapy of the present invention is based on a hydrate of cobalt-containing polyoxometalate, and can achieve the application of hypoxic tumor targeting and radiotherapy sensitization.

[0005] According to a first aspect of the present invention, the present invention provides a sensitizer for tumor radiotherapy, comprising a hydrate of cobalt-containing polyoxometalate.

[0006] The present invention discloses a sensitizer for tumor radiotherapy, which includes a hydrate of a cobalt-containing polyoxometalate, which can be metabolized in vivo, has no side effects, and is cost-effective. Other high atomic number metals (such as tungsten) in the cobalt-containing polyoxometalate can enhance the local tumor radiation dose, and the cobalt metal can be released from the sensitizer through X-rays to induce pyroptosis of hypoxic tumor cells, thereby increasing the sensitivity of hypoxic radiation-tolerant tumor cells to radiotherapy.

[0007] It should be noted that the cobalt-containing polyoxometalate may be any salt substance that can generate cobalt ions.

[0008] Furthermore, the molecular formula of the cobalt-containing polyoxometalate hydrate is: a [Co b (X z M x O y H c )] , wherein X is one or more of S, P, Ge or Si, M is one or more of W, V or Mo, A is one or more of Na, K, Li or NH4, a=1-20, b=1-8, c=1-200, x=10-60, y=1-200, z=1-4. In the hydrate of cobalt-containing polyoxometalates, M, as a high atomic number metal, plays a role of physical sensitization, with Co activating pyroptosis as the core and M as an auxiliary effect.

[0009] Further, a=5-15, b=1-5, c=50-150, x=15-20, y=100-150, z=1-3.

[0010] Furthermore, the molecular formula of the cobalt-containing polyoxometalate hydrate is Co4Na 10 O 118 H 100 P2W 18 , whose crystal structure is composed of the α isomer [PW9O 34 ] 9- The polyoxyanion is composed of four coplanar CoO6 octahedra coordinated between the polyoxyanions. This specific molecular structure takes Co ions as the core, can realize the controllable release of Co ions under radiation conditions, and utilizes high atomic number metals to further improve the effect of radiotherapy sensitization.

[0011] Furthermore, the hydrate of the cobalt-containing polyoxometalate of the present invention can be prepared by a solution method, a hydrothermal method, a water boiling method, a gas phase method or a coprecipitation method. The above preparation method is simple and easy to implement, has mild conditions, good controllability, and is easy to implement and promote.

[0012] In some specific embodiments, the preparation method of the cobalt-containing polyoxometalate hydrate is as follows: (1) Preparation of precursor B-Na8HPW9O 34 (B-PW9) Weigh sodium tungstate dihydrate and dissolve it in distilled water. Add 85% phosphoric acid during stirring. After sufficient stirring, add glacial acetic acid (the mass and concentration of the compound can be changed according to the ratio). During the addition of glacial acetic acid, the solution gradually becomes turbid and thick, and finally a large amount of white precipitate A-PW9 appears. Then filter the precipitate, place it at room temperature for at least 24 hours, and dry it in an oven at 140°C to obtain B-PW9. The above components can be adjusted in proportion. Among them, the molar ratio of sodium tungstate dihydrate, phosphoric acid and glacial acetic acid can be (10-20): 1: (10-20). In some specific embodiments, the molar ratio of sodium tungstate dihydrate, phosphoric acid and glacial acetic acid can be 14:1:15.

[0013] (2) Preparation of Na 10 [(PW9O 34 )2Co4(H2O)2]•nH2O (n=1-100) Dissolve Co(NO3)2·6H2O in water, add B-PW9, stir and heat until the solution changes from purple to wine red, and add 206 g NaCl (the mass and concentration of the compound can be changed according to the proportion). Finally, cool to room temperature and slowly crystallize to obtain Na 10 [(PW9O 34 )2Co4(H2O)2]•nH2O (PWCo). The above components can be adjusted according to the proportion.

[0014] The molar ratio of Co(NO3)2·6H2O to B-PW9 may be (1-3): 1. In some specific embodiments, the molar ratio of Co(NO3)2·6H2O to B-PW9 is 2:1.

[0015] The molar ratio of Co(NO3)2·6H2O to NaCl may be 1:(20-30). In some specific embodiments, the molar ratio of Co(NO3)2·6H2O to NaCl is 1:24.5.

[0016] Furthermore, the particle size of the cobalt-containing polyoxometalate hydrate is 1-1000 nm, for example, 1 nm, 10 nm, 50 nm, 100 nm, 300 nm, 500 nm, 800 nm or 1000 nm, etc., preferably 1-3 nm.

[0017] In order to meet actual application requirements, further, the dosage form of the sensitizer for tumor radiotherapy includes a powder dosage form, a solution dosage form, an emulsion dosage form or a liposome dosage form.

[0018] Furthermore, the sensitizer for tumor radiotherapy also includes an isotonic solution, and the isotonic solution is a sodium chloride solution, a glucose solution or a phosphate buffer solution.

[0019] In the above scheme, the sensitizer for tumor radiotherapy of the present invention also includes an isotonic solution. By dissolving the hydrate of cobalt-containing polyoxometalate in the isotonic solution and injecting it, the balance of the osmotic pressure of the fluid inside and outside the cells can be maintained, so that water and electrolytes enter the blood, thereby maintaining the normal physiological function of the body.

[0020] Furthermore, the concentration of the sodium chloride solution is 0.5-1 w / v%, preferably 0.9 w / v%; the concentration of the glucose solution is 3-8 w / v%, preferably 5 w / v%; and the concentration of the phosphate buffer solution is 0.005-0.015 M, preferably 0.01 M.

[0021] In order to achieve a better radiotherapy sensitization effect, further, in the sensitizer for tumor radiotherapy, the concentration of the cobalt-containing polyoxometalate hydrate is 5-30 mg / mL.

[0022] According to the second aspect of the present invention, the present invention also provides the use of the above-mentioned sensitizer for tumor radiotherapy in the preparation of tumor radiotherapy drugs.

[0023] Furthermore, the sensitizer for tumor radiotherapy is used for external beam radiotherapy sensitization or brachytherapy sensitization of solid tumors.

[0024] And / or, the sensitizer for tumor radiotherapy is used for radiotherapy sensitization of tumors in the first course of radiotherapy or the second course of radiotherapy.

[0025] And / or, the sensitizer for tumor radiotherapy is used in combination with one or more of clinical tumor surgery, chemotherapy and immunotherapy methods.

[0026] Furthermore, the sensitizer for tumor radiotherapy can be used at any time point during radiotherapy, for example, as a neoadjuvant (before cancer surgery) or as an adjuvant (after surgery), and can also be used for advanced tumors that cannot be removed by surgery.

[0027] Preferably, the tumor radiotherapy of the present invention is applicable to the radiotherapy of various types of tumors, and has a good radiosensitization effect on different tumors, so that the tumor volume is significantly reduced. The tumor may include one or more of skin malignancies (skin cancer), central nervous system tumors, head and neck tumors, lung cancer, breast cancer, gastrointestinal tumors, male urogenital system tumors, gynecological tumors, adrenal and retroperitoneal tumors, bone and soft tissue sarcomas (regardless of their locations), lymphomas, myeloma, leukemia, and childhood tumors.

[0028] Furthermore, skin cancer includes AIDS-related malignancies and melanoma; central nervous system tumors include tumors related to the brain, brainstem, cerebellum, pituitary gland, spinal canal, eyes, and orbits; gastrointestinal tumors include liver cancer and hepatobiliary tract cancer, colon cancer, rectal cancer and anal cancer, gastric cancer, pancreatic cancer, and esophageal cancer; male genitourinary system tumors include prostate cancer, testicular cancer, penile cancer, and urethral cancer; gynecological tumors include cervical cancer, endometrial cancer, ovarian cancer, fallopian tube cancer, vaginal cancer, and vulvar cancer, etc.; childhood tumors include Wilm's tumor, neuroblastoma, central nervous system tumors, or Ewing's sarcoma.

[0029] The tumor radiotherapy of the present invention is suitable for the treatment of primary tumors or secondary invasions, local or distant metastases, as well as in the context of prevention to avoid secondary malignant central nervous system damage, such as invasion (metastasis) from melanoma, lung cancer, kidney cancer, breast cancer, etc.

[0030] Preferably, the tumor radiotherapy of the present invention is radiation radiotherapy, wherein radiation refers to ionizing radiation, including radiation caused by X-rays, α-rays, β-rays, γ-rays, electron beams, neutron beams, ion beams, radioisotopes, etc. X-rays are a particularly preferred excitation source; the radiation voltage is generally about 2keV to 25000keV, further about 2keV to 6000keV (linear accelerator source), and further about 2keV to 1500keV (e.g., cobalt 60 source). The radiation dose of X-rays can be 1-80Gy.

[0031] Preferably, the tumor radiotherapy of the present invention is applicable to tumor radiotherapy of an organism, especially a mammal, and the mammal may be a human or a mouse.

[0032] The present invention provides a sensitizer for tumor radiotherapy, which includes a hydrate of a cobalt-containing polyoxometalate, which can be metabolized in vivo without side effects. The high atomic number metal (such as tungsten) in the cobalt-containing polyoxometalate can enhance the local tumor radiation dose, and the cobalt metal can be released from the sensitizer through X-rays to induce pyroptosis of hypoxic tumor cells, thereby increasing the sensitivity of hypoxic radiation-tolerant tumor cells to radiotherapy. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 This is a particle size distribution diagram of a sensitizer for tumor radiotherapy sensitization provided in Example 1 of the present invention.

[0035] Figure 2 This is a comparison chart of the dispersibility of the hydrate of the cobalt-containing polyoxometalate in Example 1 of the present invention in different solvents.

[0036] Figure 3 This is a diagram showing the radiosensitization effect of the cobalt-containing polyoxometalate hydrate of Example 1 of the present invention in different hypoxic tumor cells.

[0037] Figure 4 This is a diagram showing the effect of the cobalt-containing polyoxometalate hydrate of Example 1 of the present invention on inducing cell pyroptosis in hypoxic tumor cells.

[0038] Figure 5 This is a protein band diagram of the cleavage of the key proteins Cas8 and GSDMC that induce pyroptosis in hypoxic tumor cells by the hydrate of the cobalt-containing polyoxometalate in Example 1 of the present invention.

[0039] Figure 6 This is a diagram showing the radiosensitization effect of the cobalt-containing polyoxometalate hydrate of Example 1 of the present invention in an in situ breast cancer mouse model.

[0040] Figure 7 This is a diagram showing the effect of the cobalt-containing polyoxometalate hydrate of Example 1 of the present invention on the body weight of mice in an in situ breast cancer mouse model.

[0041] Figure 8 This is a diagram showing the effect of the cobalt-containing polyoxometalate hydrate of Example 1 of the present invention on the important internal organs of mice in an in situ breast cancer mouse model. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] Example 1 This embodiment provides a sensitizer for tumor radiotherapy sensitization, which includes a hydrate of a cobalt-containing polyoxometalate, and its molecular formula is Na 10 [(PW9O 34 )2Co4(H2O)2]•48H2O, the preparation method of the hydrate containing cobalt polyoxometalate comprises the following steps: (1) Preparation of precursor B-Na8HPW9O 34 (B-PW9) Weigh 600 g of sodium tungstate dihydrate and dissolve it in 740 ml of distilled water. Add 15 ml of 85% phosphoric acid while stirring. After sufficient stirring, add 110 ml of glacial acetic acid. During the addition of glacial acetic acid, the solution gradually becomes turbid and thick, and finally a large amount of white precipitate A-PW9 appears. Then filter the precipitate, place it at room temperature for at least 24 hours, and dry it in an oven at 140 °C to obtain B-PW9.

[0044] (2) Preparation of Na 10 [(PW9O 34 )2Co4(H2O)2]•48H2O Dissolve 140 mmol (42 g) of Co(NO3)2·6H2O in 1500 mL of water, add 200 g of B-PW9, stir and heat until the solution changes from purple to wine red, and add 206 g of NaCl. Finally, cool to room temperature and slowly crystallize to obtain Na 10 [(PW9O 34 )2Co4(H2O)2]•48H2O (PWCo).

[0045] The obtained hydrate of cobalt-containing polyoxometalate was subjected to a hydrate particle size test. The test method was to dissolve the hydrate of cobalt-containing polyoxometalate in deionized water and use a nanoparticle size analyzer to detect its hydrate particle size. The test results are as follows: Figure 1 As shown, the hydrated particle size of the cobalt-containing polyoxometalate hydrate of this embodiment is 1-3 nm.

[0046] 150 mg of the cobalt-containing polyoxometalate hydrate of this example was dissolved in 3 mL of water, 3 mL of 5% glucose solution (5% G), 3 mL of PBS, 3 mL of FBS, 3 mL of body fluid simulation solution or 3 mL of DMEM, respectively. Figure 2 It can be seen that the hydrate of the cobalt-containing polyoxometalate of the present invention has good dispersibility in these solvents.

[0047] Embodiment 2: The embodiment provides a sensitizer for tumor radiotherapy sensitization, which comprises the hydrate of the cobalt-containing polyoxometalate of embodiment 1 and an isotonic solution (0.01 M phosphate buffer solution), and the preparation method thereof is as follows: (1) Before use, weigh an appropriate amount of cobalt-containing polyoxometalate hydrate and dissolve it in an isotonic phosphate buffer solution to prepare a cobalt-containing polyoxometalate hydrate solution with a concentration of 0-50 mg / mL as required.

[0048] (2) Aspirate the freshly prepared cobalt-containing polyoxometalate hydrate solution into a syringe, and then filter it through a 0.22 μm sterilizing filter membrane to obtain a sterilized cobalt-containing polyoxometalate hydrate solution.

[0049] Embodiment 3: This embodiment provides an application of a sensitizer for tumor radiotherapy sensitization: (a) The PWCo nanocapsules of Example 1 were administered to 6-well plates with 1000-2000 cells per well, preferably at a concentration of 10-20 uM, and irradiated with 4 Gy of X-rays, followed by continued culture for 4-7 days until obvious cell colonies were observed. The cells were fixed with paraformaldehyde and stained with Giemsa stain and counted, verifying the inhibitory effect of the PWCo nanocapsules on the proliferation of hypoxic tumor cells under irradiation ( Figure 3 ); (b) in a confocal dish containing 20,000-40,000 cells, the PWCo nanocapsules of Example 1 are administered, preferably at a concentration of 10-20 uM, and 4 Gy of X-ray irradiation is given. After 1-2 days of culture, the cells can be observed to undergo pyroptosis under the action of PWCo and radiotherapy using a confocal microscope ( Figure 4 ), the cells irradiated after drug treatment showed obvious cell bubbling phenomenon; (c) in a large dish inoculated with tumor cells, the PWCo nanocapsules of Example 1 were administered, preferably at a concentration of 10-20 uM, and after 4 Gy of X-ray irradiation, the cells were collected and protein quantification was performed, and then the Western Blotting process was started to detect the expression of GSDMC and Caspase-8 in the cells ( Figure 5 ).

[0050] By Figure 3-Figure 5 It can be seen that the cobalt-containing polyoxometalate hydrate of the present invention exhibits good radiosensitization properties in different radiation-resistant tumor cells.

[0051] Embodiment 4: like Figure 6As shown in the results, the hydrate of cobalt-containing polyoxometalate showed good radiosensitization properties in the orthotopic breast cancer mouse model. In the orthotopic breast cancer (4T1) model of BALB / c mice aged 6 weeks, when the tumor volume was about 100mm 3 Treatment was started by intratumoral injection of 50 μL of the PWCo nanocapsules of Example 1 (administered at a concentration of 30 mg / kg) in each group. After 2 h, 2 Gy irradiation was given and the treatment process was repeated for three consecutive days. After treatment, the tumor volume was measured every 2-3 days.

[0052] Embodiment 5: like Figure 7 and Figure 8 As shown, the cobalt-containing polyoxometalate hydrate of Example 1 (taking PWCo as an example) exhibits good biocompatibility and safety in mice. In a 6-week-old BALB / c mouse orthotopic breast cancer (4T1) model, PWCo nanocapsules were injected intratumorally (administered at a concentration of 30 mg / kg for three consecutive days), and (a) the weight changes of mice were recorded every 2-3 days after administration. It can be seen that there was no effect on the weight of mice after administration; (b) the changes in organs on days 2, 7, and 14 after administration. The data showed that PWCo had no obvious side effects on mice after administration.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A sensitizer for tumor radiotherapy, characterized in that: Includes hydrates of cobalt-containing polyoxometalates.

2. The sensitizer for tumor radiotherapy according to claim 1, characterized in that: The molecular formula of the cobalt-containing polyoxometalate hydrate is: a [Co b (X z M x O y H c )] , wherein X is one or more of S, P, Ge or Si, M is one or more of W, V or Mo, A is one or more of Na, K, Li or NH4, a=1-20, b=1-8, c=1-200, x=10-60, y=1-200, z=1-4.

3. The sensitizer for tumor radiotherapy according to claim 2, characterized in that: a=5-15, b=1-5, c=50-150, x=15-20, y=100-150, z=1-3.

4. The sensitizer for tumor radiotherapy according to claim 2 or 3, characterized in that: The molecular formula of the cobalt-containing polyoxometalate hydrate is Co4Na 10 O 118 H 100 P2W 18 , whose crystal structure is composed of the α isomer [PW9O 34 ] 9- The polyoxy anions are composed of four coplanar CoO6 coordinated between the polyoxy anions.

5. The sensitizer for tumor radiotherapy according to claim 1, characterized in that: The particle size of the cobalt-containing polyoxometalate hydrate is 1-1000 nm.

6. The sensitizer for tumor radiotherapy according to claim 1, characterized in that: The dosage form of the sensitizer for tumor radiotherapy includes powder dosage form, solution dosage form, emulsion dosage form or liposome dosage form.

7. The sensitizer for tumor radiotherapy according to any one of claims 1 to 6, characterized in that: The sensitizer for tumor radiotherapy also includes an isotonic solution, which is a sodium chloride solution, a glucose solution or a phosphate buffer solution.

8. The sensitizer for tumor radiotherapy according to claim 7, characterized in that: The concentration of the sodium chloride solution is 0.5-1 w / v%, preferably 0.9 w / v; the concentration of the glucose solution is 3-8 w / v%, preferably 5 w / v; the concentration of the phosphate buffer solution is 0.005-0.015 M, preferably 0.01 M.

9. The sensitizer for tumor radiotherapy according to claim 7 or 8, characterized in that: In the sensitizer for tumor radiotherapy, the concentration of the hydrate containing cobalt polyoxometalate is 5-30 mg / mL.

10. Use of the sensitizer for tumor radiotherapy according to any one of claims 1 to 9 in the preparation of tumor radiotherapy drugs.

Images