Anti-neoplastic drugs 抗肿瘤药物

1. Anti-neoplastic drugs抗肿瘤药物 2011.12

2. 讨论题 • 从不感冒者得癌症的机会大，还是易患感冒者得癌症机会大？ • 为什么？ • 过敏发生率，发达国家发生率高，还是贫困国家高？

3. 生物学“僭越效应”。 僭越：超越本分 • “不干不净，吃了没病”。一定病菌刺激可以使人体免疫系统功能增强。 • 过敏发生率：发达国家儿童发生率高于贫困国家 • 金丝桃中的抗抑郁成分受到一定刺激如昆虫袭击后，含量会增加 • 从不感冒者患癌症机会大5倍，因为感冒促使干扰素产生。 • 砷剂少量应用，促白细胞分化，治疗白血病

4. 人为什么会生癌 Why cancer happens? • 人体：1000万亿个细胞 • 病毒、霉菌、射线、化学致癌剂; 遗传因素；免疫功能低下……直接、间接影响DNA • >3000万个癌变细胞，可能成为癌症 Women who inherit a single defective copy of either of the tumor suppressor genes BRCA1 and BRCA2 have a significantly increased risk of developing breast cancer.

5. Cancer • Cancer is a disease characterized by a shift in the control mechanisms that govern cell survival, proliferation, and differentiation. 1. uncontrolled proliferation 2. dedifferentiation（去分化） and loss of function 3. invasiveness 4. metastasis（转移）

7. Basic facts of cancer • most common cause of death from disease （中国第一位死因；死180万/年） • morbidity getting higher gradually • chemotherapy, some curative, others palliative • almost all the anticancer drugs can be produced in China • 国际抗癌联盟第21届世界抗癌大会，2010，8月18日-21日，中国 • 2008，全球1270万人患癌，死760万

8. One in seven people will be diagnosed with cancer during their lifetime. Cancer Liver cancer Lung cancer 2.6 million new cancer cases per year in China currently and the incidence is increasing rapidly due to longer life-span and change of life styles.

9. Causes of cancer • genetic predisposition: tumor suppressor genes deleted or damaged, etc. • exposure to environmental carcinogens: radiation, chemicals (including ones in food), viruses, … • In a healthy body immune system can recognize and destroy foreign cells. If … • 注意生活方式（吸烟；肥胖；…）因素、传染病等感染因素、职业或环境因素 • 1／5癌症由慢性感染引起，如人类乳头瘤病毒引起宫颈癌；乙肝病毒引起肝癌

11. Treatment of cancer There are three main approaches to treating established cancer: Surgery, Radiation therapy, Chemotherapy Breast cancer Surgery Radiation Chemotherapy Chemotherapy of cancer, as compared with that of bacterial disease, presents a difficult problem. In biochemical terms, cancer cells and normal cells are so similar in most respects that it is more difficult to find general, exploitable, biochemical differences between them.

12. Surgery • Radiotherapy • Chemotherapy • Endocrine therapy • Immunotherapy • Biological therapy

13. Anticancer drug development • in vitro assays for measuring drug sensitivity of a battery of human tumor cells • in vivo, a few well-characterized transplantable animal tumor systems • preclinical toxicological and limited pharmacological studies in animals • phase I clinical trials • …

14. Summary of the main sites of action of cytotoxic agents. For some groups of drugs, only one or two examples are given.

15. Resistance to anticancer drugs • primary resistance • Acquired resistance multidrug resistance, associated with increased expression of a normal gene (the MDR1 gene) for a cell surface glycoprotein (P-glycoprotein) involved in drug efflux

16. Simplified outline of the genesis of cancer. The genesis of cancer is usually multifactorial, involving more than one genetic change. 'Other factors', as specified above, may involve the actions of promoters, cocarcinogens, hormones, etc. which, while not themselves carcinogenic, increase the likelihood that genetic mutation(s) will result in cancer.

17. alkylating agents （烷化剂） • cyclophosphamide（环磷酰胺）, mechlorethamine（氮芥）, melphalan（美法仑）, chlorambucil（苯丁酸氮芥），thiotepa（塞替哌），busulfan（白消安）， carmustine (卡莫司汀), lomustine (洛莫司汀), semustine（司莫司汀） • Related platinum analogs: cisplatin, oxaliplatin • Mechanism: alkylation of DNA within the nucleus represent the major interactions that lead to cell death

18. The effects of bifunctional alkylating agents on DNA.Note the cross-linking of two guanines. A, adenine; C, cytosine; G, guanine; T, thymine.

19. Discovery of cis-platinum It all started by accident over 40 years ago in the laboratory of physicist-turned-biophysicist Barnett Rosenberg at Michigan State University, East Lansing, United States. Rosenberg was interested in applying electromagnetic radiation to bacterial and mammalian cells to investigate whether electric or magnetic dipole fields might be involved in cell division. Inadvertently, in the early experiments using Escherichia coli, a set of platinum electrodes (considered to be inert) was included in the growth chamber. When the field was turned on, the bacteria appeared as very long filaments (300 times the usual length) rather than as the normal short rods. This effect was shown not to be due to the electric field but, rather, to electrolysis products arising from the platinum electrodes (TIMELINE). Detailed chemical analysis identified two active complexes — the neutral cis-isomer [PtII (NH3)2Cl2], which went on to be cisplatin, and a platinum(IV) analogue, cis-diamminetetrachloroplatinum( IV).

20. Discovery of cis-platinum • It all started by accident over 40 years ago in the laboratory of physicist-turned-biophysicist Barnett Rosenberg at Michigan State University, East Lansing, United States. Rosenberg was interested in applying electromagnetic radiation to bacterial and mammalian cells to investigate whether electric or magnetic dipole fields might be involved in cell division. • Inadvertently, in the early experiments using Escherichia coli, a set of platinum electrodes (considered to be inert) was included in the growth chamber. When the field was turned on, the bacteria appeared as very long filaments (300 times the usual length) rather than as the normal short rods. This effect was shown not to be due to the electric field but, rather, to electrolysis products arising from the platinum electrodes (TIMELINE). Detailed chemical analysis identified two active complexes — the neutral cis-isomer [PtII (NH3)2Cl2], which went on to be cisplatin, and a platinum(IV) analogue, cis-diamminetetrachloroplatinum( IV).

21. 草酸铂发现故事 • 1976，日本名古屋市立大学药学院化学家木古教授：草酸铂抗癌 • 1979：美国专利 • 寻找了至少10家本土企业，均遭拒绝

22. 经一日本人在法国的公司代理找诸多欧洲企业，均被拒经一日本人在法国的公司代理找诸多欧洲企业，均被拒 • 15年间找不到开发伙伴 • 欧洲几家大药厂历4年余参与开发，找不准适应证 • I期临床发现神经毒性，放弃

23. 瑞士德彪公司毛沃内：草酸铂没有肾毒性，没有骨髓抑制，消化道毒性低，神经毒性可控，无交叉耐药。瑞士德彪公司毛沃内：草酸铂没有肾毒性，没有骨髓抑制，消化道毒性低，神经毒性可控，无交叉耐药。 • 虽然草酸铂毒性大，其毒性与注射次数有关 • 实验：如减少用量，拉开注射间隔，毒性↓。

24. 1989：毛沃内以“跳水价”购买了草酸铂专利授权──一个一度曾被众人抛弃了的新药！1989：毛沃内以“跳水价”购买了草酸铂专利授权──一个一度曾被众人抛弃了的新药！ • 签约，转让方交出几捆材料 • 附送：仓库里几公斤原料（每公斤3万美元）

25. 仔细研究全部数据，发现“时辰治疗学”试验中有几例大肠癌患者缓解。仔细研究全部数据，发现“时辰治疗学”试验中有几例大肠癌患者缓解。 • 以大肠癌为目标，从头开始细胞水平、动物模型研究，终于创造出最佳大肠癌化疗方案。 • 法国巴黎创立一临床研究中心，负责协调在全欧洲实施的临床试验。3,000多例临床验证开拓了草酸铂临床应用新方法：与5-氟尿嘧啶联合治疗大肠癌。

26. 1996：草酸铂获第一个新药注册证书，两年后欧盟注册。1996：草酸铂获第一个新药注册证书，两年后欧盟注册。 • 2002：美国FDA经7周审查，批准草酸铂在美上市，审查时间短于以前审查的其他所有抗肿瘤药 • 德彪公司将草酸铂的销售权卖给法国大型制药企业赛诺菲－圣德拉堡公司

27. 目前：草酸铂已成为治疗大肠癌的主要用药，在60多个国家上市 • 2005年全球销售23亿美元 • 依转让合同，德彪从赛诺菲-安万特公司的销售利润中每年分得数亿美元 • 赛诺菲－圣德拉堡公司心疼不已：如果当年预测到草酸铂有这么好的市场，就不会同意分给德彪四分之一的销售利润！

28. Antimetabolites（抗代谢药） • Mechanism: biochemical pathways that have thus far proved to be most vulnerable to antimetabolites have been those relating to nucleotide and nucleic acid synthesis.

29. Antimetabolites • They are structurally similar to endogenous compounds mostly related to nucleotide metabolism • They act as antagonists of: • Folic acid (methotrexate) • Purines (Mercaptopurine and thioguanine) • Pyrimidine (fluorouracil, cytarabine)

30. Antimetabolites • 6-Thioguanine（6-硫鸟嘌呤） • Pemetrexed（培美曲塞） • Methotrexate（甲氨蝶呤） • 6-Mercaptopurine（6-巯嘌呤） • Gemcitabine（吉西他滨） • 5-Fluorouracil（氟尿嘧啶） • Fludarabine（氟达拉滨） • Cytarabine（阿糖胞苷） • Cladribine（克拉屈滨） • Capecitabine（卡培他滨） • …

31. Antimetabolits: sites of drug action

32. Methotrexate

33. Inhibition of dihydrofolate reductase by MTX MTX

34. Mechanism of the cytotoxic action of 5-FU 5-FU is converted to 5-FdUMP, which competes with deoxyuridine monophosphate (dUMP) for the enzyme thymidylate synthetase. 5-FU = 5-fluorouracil 5-FUR = 5-fluorouridine 5-FUMP = 5-fluorouridine monophosphate 5-FUDP = 5-fluorouridine diphosphate 5-FUTP = 5-fluorouridine triphosphate dUMP = deoxyuridine monophosphate dTMP = deoxythymidine monophosphate 5-FdUMP = 5-fluorodeoxyuridine monophosphate. 5-FU

35. Plant alkaloids • vinblastine（长春碱） • vincristine（长春新碱） • vinorelbing (长春瑞滨） • epipodophyllotoxin（表鬼臼毒素） • camptothecin（喜树碱） • taxane（塔三烷）: paclitaxel（紫杉醇）; docetaxel（多烯紫杉醇）

36. Teniposide Docetaxel Vinblastine Vincristine Vinorelbine Irinotecan

37. These drugs block the formation of mitotic spindle by preventing the assembly of tubulin dimers into microtubules They act primarily on the M phase of cancer cell cycle Resistance is due to  efflux of drugs from tumor cells Vinka alkaloids (Vinblastine, vincristine)

38. Etoposide依托泊苷 & Teniposide • Acts by inhibiting topoisomerase II • These drugs are most active in late S and early G2 phase • Used in combination with paclitaxel in small cell carcinoma of lung, prostrate and testicular carcinomas Other topoisomerase inhibitors: • Topotecan, Irinotecan • Both act by inhibiting topoisomerase-I

39. Topoisomerase inhibitors

40. Paclitaxel 紫杉醇

41. Undisturbed Pacific Yew（红豆杉） bark contains paclitaxel The bark is peeled and processed to provide paclitaxel

42. Discovery of Paclitaxel • 1962.8.21, botanists, Arthur S. Barclay, collected bark from a single Pacific yew tree, Taxus brevifolia, in a forest north of the town of Packwood in Washington State as part of a four month trip collecting material from over 200 different species. One of the Taxus samples was found to be cytotoxic in a cellular assay on 22 May 1964. • late 1964 or early 1965, the fractionation and isolation laboratory run by Monroe E. Wall in Research Triangle Park, North Carolina, began work on fresh Taxus samples, isolating the active ingredient in September 1966. They named the pure compound 'taxol' in June 1967.

43. Discovery of Paclitaxel By 1969 28kg of crude extract had been isolated from 2,600 pounds of bark, yielded only 10g of pure material. BMS filed an NDA which was given FDA approval at the very end of 1992.

44. Discovery of Paclitaxel • 1969, 28 kg of crude extract isolated from 2,600 pounds of bark, yielded only 10 g of pure material. • Bristol Myers Squibb filed an new drug application (NDA) which was given FDA approval at the very end of 1992.

45. Taxol content varies in the Yew tree (0.001 to 0.01 % of the dry bark weight). It is generally considered to take 3 to 10 trees per patient. • 36000 trees are required to provide 327200 kg of bark (about 9 kg/tree) from which 24 kg of paclitaxel can be extracted. (about 0.66 g/tree). • Approximately 1 kg is required for 480 cancer patients or 2.08 g per person or 3.15 trees per person. Others have claimed this number can be as high as 10 trees per person depending on the size of the trees

46. Currently, all paclitaxel production for BMS uses plant cell fermentation (PCF) technology developed by the biotechnology company Phyton and carried out at their plant in Germany. This starts from a specific taxus cell line propagated in aqueous medium in large fermentation tanks. Paclitaxel is then extracted directly, purified by chromatography and isolated by crystallization. Compared to the semisynthesis, PCF eliminates the need for many hazardous chemicals and saves a considerable amount of energy.

47. These drugs act by interfering with mitotic spindle They prevent micotubule disassembly into tubulin monomers ADR Neutropenia Peripheral neuropathy Paclitaxel & Docetaxel

48. Antitumor antibiotics • binding to DNA through intercalation between specific bases and block the synthesis of RNA, DNA, or both; cause DNA strand scission; and interfere with cell replication • Anthracyclines（蒽环类）: • Doxorubicin (adriamycin)多柔比星（阿霉素） • Daunorubicin （佐柔比星） • Bleomysin（博莱霉素） • Dactinomycin（放线菌素） • Mitomycin （丝裂霉素）

49. These drugs intercalate between base pairs, inhibit topoisomerase II and also generate free radicals They block RNA and DNA synthesis and cause strand scission *These are CCNS drugs Used as a component in ABVD regimen in Hodgkin’s lymphoma Doxorubicin & Daunorubicin

50. Cartoon diagram of two doxorubicin molecules intercalating DNA