CN-121987570-A - Liposome for resisting angiogenesis and downregulating PD-L1 protein, and preparation method and application thereof

Abstract

The invention belongs to the technical field of medicines, and discloses a liposome for resisting angiogenesis and downregulating PD-L1 protein, and a preparation method and application thereof. The active targeting liposome of NGR modified co-supported acitinib and siRNA PD‑L1 is prepared by a film dispersion method and a lipid coextrusion method. The method has the advantages of simple preparation process, low cost, good stability and high repeatability. Axi/siRNA PD‑L1 @NGR-Lipo can inhibit tumor micro-angiogenesis, remodel tumor vascular system, normalize tumor blood vessels, inhibit tumor metastasis and improve tumor immunosuppression microenvironment, silence tumor cell surface PD-L1 protein, release tumor immune escape, and enhance tumor immunotherapy. Axi/siRNA PD‑L1 @ NGR-Lipo achieve enhanced anti-tumor effects by combining anti-angiogenic therapies with immune checkpoint blocking therapies. The liposome has simple and quick preparation process, is easy to amplify and industrialize, and has good development prospect in the aspect of clinical application transformation.

Inventors

• HUANG WEI
• JIN MINGJI
• GONG LIMING
• GUAN YOUYAN
• GAO ZHONGGAO
• LIU YANHONG
• FENG JING
• XIAO CONGCONG
• LIU CHENFEI
• CHEN LIQING

Assignees

• 中国医学科学院药物研究所

Dates

Publication Date

20260508

Application Date

20241105

Claims (10)

1. 1. A liposome for anti-angiogenic and down-regulating PD-L1 protein, wherein the liposome is comprised of a phospholipid bilayer encapsulating an anti-angiogenic drug and a hydrophilic vesicle encapsulating a protamine complex of siRNA PD-L1 .
2. 2. A liposome for anti-angiogenic and down-regulating PD-L1 protein according to claim 1, wherein said phospholipid bilayer is composed of cholesterol, DOPC and DSPE-PEG 2000-NGR.
3. 3. A liposome for anti-angiogenic and down-regulating PD-L1 protein according to claim 1, wherein the anti-angiogenic drug is selected from one or more of sorafenib, sunitinib, pezopanib, acitinib, apatinib and An Luoti ni, preferably is acitinib.
4. 4. A method for preparing a liposome for anti-angiogenic and down-regulating PD-L1 protein, said method comprising: S1, dissolving cholesterol, DOPC, DSPE-PEG2000-NGR and acitinib in an organic solvent according to a certain proportion, and removing the organic solvent by reduced pressure rotary evaporation under 40 ℃ water bath; s2, adding deionized water to hydrate the phospholipid membrane obtained in the step S1 at 40 ℃, and crushing under ultrasonic waves of a probe to obtain a liposome solution; S3, uniformly mixing the siRNA PD-L1 and the protamine according to a certain mass ratio, and swirling for a period of time to obtain a protamine compound solution of the siRNA PD-L1 ; And S4, extruding the liposome solution obtained in the step S2 and the protamine complex solution of siRNA PD-L1 obtained in the step S3 through a polycarbonate film for multiple times by a lipid extruder to obtain the liposome.
5. 5. The preparation method according to claim 4, wherein the mass ratio of cholesterol, DOPC, DSPE-PEG2000-NGR and acitinib is 4:20:4:1.
6. 6. The preparation method according to claim 4, wherein the organic solvent comprises an organic solvent A and an organic solvent B, wherein the organic solvent A is used for dissolving cholesterol, DOPC and DSPE-PEG2000-NGR, and the organic solvent B is used for dissolving the acitinib; The organic solvent A is selected from one or more of chloroform, dichloromethane, ethanol and acetone, and is preferably dichloromethane; The organic solvent B is selected from one or more of DMSO, methanol and acetonitrile, preferably methanol.
7. 7. The method according to claim 4, wherein the mass ratio of siRNA PD-L1 to protamine is 1:1-1:10, preferably 1:5.
8. 8. The method according to claim 4, wherein the swirling time is 1 to 10 minutes, preferably 5 minutes.
9. 9. The method according to claim 4, wherein the polycarbonate film has a pore size of 0.1 to 1. Mu.m, preferably 0.2. Mu.m.
10. 10. Use of a liposome for anti-angiogenesis and down-regulating PD-L1 protein according to claim 1, in the manufacture of a medicament for the treatment of malignant tumors.

Description

Liposome for resisting angiogenesis and downregulating PD-L1 protein, and preparation method and application thereof Technical Field The invention belongs to the technical field of medicines, and particularly relates to a liposome for resisting angiogenesis and downregulating PD-L1 protein, and a preparation method and application thereof. Background Angiogenesis plays a key role in the development of malignant tumors. More mechanical stress in tumor tissue causes uneven thickness and structural deformation of tumor vessels, which are densely budded in an irregular convoluted manner, which tends to hinder blood flow. In addition, fragile and highly permeable tumor vessels have irregular endothelial and pericyte arrangements, resulting in blood leakage and discontinuous perfusion. The abnormal space structure reduces blood flow, reduces oxygen and nutrition supply, and makes the tumor microenvironment present acidic environment, hypoxia and high pressure. These factors can further lead to dysfunction and structural abnormalities of tumor blood vessels, and stress the acidic and hypoxic tumor microenvironment, thereby promoting tumor angiogenesis, invasion and metastasis, forming a vicious circle. Meanwhile, the tumor neovascular with incomplete structure and function can also obstruct the anti-tumor medicine from entering into tumor tissues, and reduce the curative effect of the medicine. Therefore, anti-angiogenesis therapy for tumor neovasculature can improve drug delivery, reduce metastasis of tumor cells, and become a new means of anti-tumor therapy. In addition, the abnormal vascular structure within tumors not only causes acidic, hypoxic and high pressure tumor microenvironment, but also an important immune escape mechanism. There is growing evidence that angiogenesis promotes immune escape by inducing a highly immunosuppressive tumor microenvironment, affecting immune responses by inhibiting DC cell maturation. Angiogenesis-related VEGF factors have also been found to inhibit T cell development and function and promote T cell depletion by upregulating immune checkpoints, thereby exacerbating the immunosuppressive microenvironment of tumor tissue. Therefore, the combination of the anti-angiogenesis therapy and the immune checkpoint blocking therapy not only can remodel the tumor vasculature, improve the tumor microenvironment and reduce tumor metastasis, but also can enhance the infiltration of immune cells, relieve the immune escape of tumor cells and enhance the tumor immunotherapy, and the combination of the two therapies is expected to realize the synergistic and efficient anti-tumor effect. In view of the basis and the current state of the art, the inventors of the present application intend to utilize liposomes co-loaded with acitinib and siRNA PD-L1 to achieve combined anti-angiogenic and silencing of PD-L1 proteins for anti-tumor therapy. Disclosure of Invention The invention provides a liposome for resisting angiogenesis and down-regulating PD-L1 protein, a preparation method and application thereof, and aims to solve the problems that tumors are easy to metastasize, therapeutic drugs are difficult to enter the inside of tumors, and the tumors are difficult to be in microenvironment due to abnormal vascular structures and functions in tumor tissues. The active targeting liposome carrying the acitinib and the siRNA PD-L1 is prepared by a film dispersion method and a lipid coextrusion method, on one hand, the liposome can target tumor neovascularization and tumor tissues through NGR peptide, inhibit the generation of the tumor neovascularization, remodel tumor vasculature, improve tumor microenvironment and realize anti-tumor effect. On the other hand, siRNA PD-L1 can improve tumor immunotherapy by silencing PD-L1 protein on the surface of tumor cells, relieving immune escape of tumor cells. The liposome prepared by the invention realizes the combined application of anti-angiogenesis therapy and immune checkpoint blocking therapy, and improves the anti-tumor efficacy. Specifically, the invention is realized by the following technical scheme: in a first aspect, the present invention provides a liposome for anti-angiogenesis and down-regulating PD-L1 protein, wherein the liposome is composed of a phospholipid bilayer encapsulating an anti-angiogenesis drug and a hydrophilic vesicle encapsulating a protamine complex of siRNA PD-L1. In the present invention, the phospholipid bilayer is composed of cholesterol, DOPC and DSPE-PEG 2000-NGR. In the present invention, the anti-angiogenic drug is selected from one or more of sorafenib, sunitinib, pezopanib, acitinib, apatinib and An Luoti b, preferably acitinib. In a second aspect, the present invention provides a method for preparing a liposome for anti-angiogenesis and down-regulating PD-L1 protein, which is characterized in that the method comprises the steps of: s1, dissolving cholesterol, DOPC, DSPE-PEG2000-NGR and acitinib in an organic solvent acco