双氢青蒿素防治乳腺癌作用机制的研究进展

乳腺癌是最常见的癌症之一,属于典型的异质性恶性肿瘤,临床结局不佳。双氢青蒿素是青蒿素在体内的主要代谢产物,可抑制乳腺癌肿瘤细胞增殖、促进肿瘤细胞凋亡、阻止肿瘤细胞转移、诱导细胞自噬,因此对双氢青蒿素抗乳腺癌的作用机制进行总结,希望为双氢青蒿素的临床使用提供参考。     

植物多糖抗乳腺癌作用的研究进展

乳腺癌是女性常见的恶性肿瘤之一,其发病率和死亡率呈逐年上升趋势。目前治疗乳腺癌的大多数药物会产生一些不良反应。植物多糖具有多种生物活性,可通过抑制细胞增殖、抑制细胞迁移和侵袭、诱导细胞凋亡、调节细胞周期、抑制肿瘤血管生成、免疫调节、抗氧化等途径抗乳腺癌。综述了植物多糖抗乳腺癌的作用机制研究进展,为植物多糖开发抗乳腺癌新药提供参考。     

bcl-2基因对乳腺癌细胞多药耐药性的影响

乳腺癌细胞的多药耐药性是临床上常见的影响乳腺癌化疗效果的原因之一.近年来发现,抗凋亡基因bcl-2在乳腺癌细胞多药耐药性的产生过程中起到了重要的作用.bcl-2基因通过抑制乳腺癌细胞的凋亡、延长细胞生存时间等机制,诱导乳腺癌细胞对化疗药物产生耐药性.用反义寡核苷酸抑制 bcl-2的表达可以增加肿瘤细胞对化疗药物的敏感性.     

去甲斑蝥素在乳腺癌中的研究进展

乳腺癌是我国最常见的女性恶性肿瘤。传统中药及其提取物因具有单药多靶点、低毒的特点,成为乳腺癌治疗的研究热点。去甲斑蝥素是一种新型人工合成抗肿瘤药物,具有升白细胞、抗肿瘤的作用。其抗肿瘤作用机制包括抗血管生成,促进肿瘤细胞凋亡,抑制肿瘤细胞增殖、侵袭与转移等。以斑蝥为主要来源的中成药在乳腺癌的临床应用中贯穿全程。本文就近年来去甲斑蝥素在乳腺癌中的研究进展进行综述。     

桦木酸抗炎作用与机制

目的 对桦木酸的抗炎作用与机制进行综述。方法 检索归纳有关桦木酸抗炎作用的文献,对其作用途径及机制进行了分析。结果 桦木酸对实验性炎症模型及其他模型有显著的抗炎作用,桦木酸抗炎作用机制涉及糖皮质激素受体、一氧化氮、氧化应激、免疫调节、细胞因子和黏附分子、炎性信号通路等。此外,桦木酸与其他天然产物还有协同的抗炎作用。结论 桦木酸通过多途径发挥抗炎作用,抗炎活性研究对于探讨桦木酸治疗疾病的作用机制有着重要意义。     

绿茶有效成分表没食子儿茶素没食子酸酯的肿瘤防治作用

表没食子儿茶素食子酸酯（ＥＧＣＧ）是绿茶中最重要的有效成分之一，本文综述ＥＧＣＧ的抑制癌变作用及其主要作用机制，研究表明，ＥＧＣＧ有抗突变、抗促癌、抗氧化以及抑制肿瘤细胞增殖、促进肿瘤细胞凋亡和分化的作用，并影响癌基因的表达等。     

乌苏酸抗肿瘤作用研究进展

乌苏酸是一种广泛存在于天然药物中的五环三萜类化合物。乌苏酸不仅能抑制肿瘤细胞增殖、诱导肿瘤细胞分化和凋亡,抗侵袭、抗血管生成,而且具有免疫增强功能。为了促进其进一步的开发研究,本文就近年来乌苏酸抗肿瘤作用研究进展作一综述。     

芦荟大黄素抗肿瘤作用机制的研究进展

芦荟大黄素为蒽醌类化合物,主要来源于芦荟、大黄、巴天酸模、山扁豆等植物中,具有良好的抗菌、泻下作用。近年来,研究者在对芦荟大黄素药理活性的研究中发现其有巨大的抗肿瘤潜力。从诱导肿瘤细胞凋亡、抑制肿瘤细胞增殖、抑制肿瘤细胞侵袭和转移、诱导肿瘤细胞自噬、抗炎、免疫调节方面对芦荟大黄素的抗肿瘤作用机制进行综述,为其进一步的应用、开发提供参考。     

塞来昔布抗肿瘤效应及其作用机制的研究进展

塞来昔布是一种特异性环氧化酶-2抑制剂,具有抗炎、镇痛和退热作用。近年来,塞来昔布的抗肿瘤作用受到广泛关注,已被应用于消化道肿瘤、乳腺癌、肺癌、肝癌、前列腺癌等的化学辅助治疗和放射治疗增敏。综述了塞来昔布的抗肿瘤效应,并总结了其作用机制,如抑制肿瘤细胞增殖、抑制肿瘤细胞侵袭和转移、抑制肿瘤新生血管生成、诱导肿瘤细胞分化、诱导肿瘤细胞凋亡、调节肿瘤免疫、逆转肿瘤细胞的多药耐药性,以期为塞来昔布的深入研究和临床肿瘤防治提供用药参考。     

藤黄酸在乳腺癌治疗中的研究进展

藤黄酸作为中药藤黄的主要生物活性成分,通过多种机制发挥抗肿瘤作用,包括诱导细胞凋亡、抑制肿瘤血管的生成和转移以及逆转肿瘤的多药耐药等;尤其是在乳腺癌治疗中可发挥多种抗肿瘤作用,有望成为乳腺癌的治疗药物。但藤黄酸自身存在缺陷,如水溶性差、半衰期短等,限制其临床应用。随着纳米载药制剂的不断发展,有望改善藤黄酸的不足,发挥藤黄酸强大的抗肿瘤作用。因此,综述近五年藤黄酸治疗乳腺癌的相关文献,以期为最大化藤黄酸抗乳腺癌奠定基础。     

Betulinic acid,a bioactive pentacyclic triterpenoid,inhibits skeletal-related events induced by breast cancer bone metastases and treatment

Many breast cancer patients experience bone metastases and suffer skeletal complications. The present study provides evidence on the protective and therapeutic potential of betulinic acid on cancer-associated bone diseases. Betulinic acid is a naturally occurring triterpenoid with the beneficial activity to limit the progression and severity of cancer, diabetes, cardiovascular diseases, atherosclerosis, and obesity. We first investigated its effect on breast cancer cells, osteoblastic cells, and osteoclasts in the vicious cycle of osteolytic bone metastasis. Betulinic acid reduced cell viability and the production of parathyroid hormone-related protein (PTHrP), a major osteolytic factor, in MDA-MB-231 human metastatic breast cancer cells stimulated with or without tumor growth factor-β. Betulinic acid blocked an increase in the receptor activator of nuclear factor-kappa B ligand (RANKL)/osteoprotegerin ratio by downregulating RANKL protein expression in PTHrP-treated human osteoblastic cells. In addition, betulinic acid inhibited RANKL-induced osteoclastogenesis in murine bone marrow macrophages and decreased the production of resorbed area in plates with a bone biomimetic synthetic surface by suppressing the secretion of matrix metalloproteinase (MMP)-2, MMP-9, and cathepsin K in RANKL-induced osteoclasts. Furthermore, oral administration of betulinic acid inhibited bone loss in mice intra-tibially inoculated with breast cancer cells and in ovariectomized mice causing estrogen deprivation, as supported by the restored bone morphometric parameters and serum bone turnover markers. Taken together, these findings suggest that betulinic acid may have the potential to prevent bone loss in patients with bone metastases and cancer treatment-induced estrogen deficiency.     

白桦酸类化合物的研究进展

白桦酸类化合物是一类可以从多种植物中分离得到的天然产物，包括白桦酸、23-羟基白桦酸、白桦素及其衍生物等，是一类结构及作用机制相对新颖、具有抗HIV-1和抗肿增活性的天然化合物。对这类化合物的结构修饰和改造，目前已经获得大量具有良好生物活性的衍生物。现对这方面的研究进展进行综述。     

桦木酸对人肿瘤细胞的抗癌活性筛选

目的研究桦木酸(betulinic acid,BetA)对9种人肿瘤细胞的作用。方法采用噻唑兰(MTT)比色法测定KB(口腔上皮癌细胞)、OVCAR(卵巢癌细胞)、Bcap-37(乳腺癌细胞)、A2780(卵巢癌细胞)、HT-29(大肠癌细胞)、LS-1747(结肠腺癌细胞)、SMMC-7721(肝癌细胞)、PC-14(肺癌细胞)、K562(白血病细胞)对桦木酸及常用抗癌药cDDP(顺铂)、Taxol(紫杉醇)的敏感性。结果KB细胞对BetA最为敏感(IC50为11.6μmol.L-1),其次为LS-1747(IC50为12.5μmol.L-1)、SMMC-7721(IC50为25.0μmol.L-1)。结论桦木酸可以用作特异性的细胞增殖抑制剂。     

Advances in the study of structural modifications and biological activities of betulinic acids

Betulinic acids are lupine-type pentacyclic triterpenoid saponins commonly found in some plants of Betulaceae family, especially in the bark of betula alba (birch). The potent anti-HIV and anti-tumor activities of betulinic acids have been greatly concerned. The natural betulinic acids include betulinic acid, 23-hydroxy betulinic acid, betulin and so on. Some investigations on the structural modifications of betulinic acids were carried out, and many derivatives with excellent biological activity have been obtained nowadays. In this paper, the research advances of the structural modification of betulinic acids, as well as their anti-HIV and anti-tumor activities are reviewed.     

白藜芦醇抗肿瘤药理作用机制研究进展

白藜芦醇是一种天然单体化合物,属于非黄酮类的多酚化合物,存在于多种植物中。现代药理研究发现,白藜芦醇具有抗炎、抗氧化、抗肿瘤、调节代谢与机体免疫等药理活性。白藜芦醇对结肠癌、胰腺癌、卵巢癌、乳腺癌等多种肿瘤细胞均有抑制作用,其抗肿瘤作用逐渐成为研究热点。白藜芦醇可以通过抑制肿瘤细胞的增殖、诱导肿瘤细胞凋亡、抑制肿瘤细胞侵袭和转移、调节机体免疫功能、直接作用于相关靶点等发挥抗肿瘤活性。就白藜芦醇在不同肿瘤细胞中发挥的抗肿瘤作用及其机制进行综述,以期为抗肿瘤新药的研发提供参考依据。     

Pharmacological properties of the ubiquitous natural product betulin.

Betulin (lup-20(29)-ene-3beta,28-diol) is an abundant naturally occurring triterpene and it is found predominantly in bushes and trees forming the principal extractive (up to 30% of dry weight) of the bark of birch trees. Presently, there is no significant use for this easily isolable compound, which makes it a potentially important raw material for polymers and a precursor of biologically active compounds. Betulin can be easily converted to betulinic acid, which possesses a wide spectrum of biological and pharmacological activities. Betulinic acid has antimalarial and anti-inflammatory activities. Betulinic acid and its derivatives have especially shown anti-HIV activity and cytotoxicity against a variety of tumor cell lines comparable to some clinically used drugs. A new mechanism of action has been confirmed for some of the most promising anti-HIV derivatives, which makes them potentially useful additives to the current anti-HIV therapy. Betulinic acid is specifically cytotoxic to several tumor cell lines by inducing apoptosis in cells. Moreover, it is non-toxic up to 500 mg/kg body weight in mice. The literature concerning derivatization of betulin for structure-activity relationship (SAR) studies and its pharmacological properties is reviewed.     

Betulinic acid decreases expression of bcl-2 and cyclin D1, inhibits proliferation, migration and induces apoptosis in cancer cells

Betulinic acid (BA) is a pentacyclic triterpene found in many plant species, among others in the bark of white birch Betula alba. BA was reported to display a wide range of biological effects, including antiviral, antiparasitic, antibacterial and anti-inflammatory activities, and in particular to inhibit growth of cancer cells. The aim of the study was further in vitro characterization of BA anticancer activity. In this study, we demonstrated a remarkable antiproliferative effect of BA in all tested tumor cell cultures including neuroblastoma, rabdomyosarcoma-medulloblastoma, glioma, thyroid, breast, lung and colon carcinoma, leukemia and multiple myeloma, as well as in primary cultures isolated from ovarian carcinoma, cervical carcinoma and glioblastoma multiforme. Furthermore, we have shown that BA decreased cancer cell motility and induced apoptotic cell death. We also observed decrease of bcl2 and cyclin D1 genes expression, and increase of bax gene expression after betulinic acid treatment. These findings demonstrate the anticancer potential of betulinic acid and suggest that it may be taken into account as a supportive agent in the treatment of cancers with different tissue origin.