Ohbayashi M, Yasuda M, Kawakami I, Kohyama N, Kobayashi Y, Yamamoto T
Department of Clinical Pharmacy, School of Pharmacy, Showa University, Shinagawa-ku, Tokyo 142-8555, Japan.
Exp Oncol. 2008 Dec;30(4):276-82.
To examine the effect of various components of extracellular matrix (ECM) on acquisition of drug resistance to taxol and camptothecin by breast carcinoma cell line MCF-7.
Cancer cells were cultured on bovine serum albumin (BSA), vitronectin (VN), fibronectin (FN), collagen type I (COL-I), or Matrigel-coated plates with or without taxol (paclitaxel) or camptothecin treatment. The effect of anticancer drugs on cell growth was accessed by XTT assay, and the alterations of cellular morphology were examined by phase contrast microscopy. Immunofluorescence study was performed using monoclonal anti-beta-tubulin antibody.
All cell lines showed a significant decrease in cell survival when treated with anticancer drugs without components of ECM, whereas survival rates of Caco-2, MCF-7 and NCI-H292 were significantly increased when cells were cultured on COL-I- and Matrigel-coated dishes after treatment with paclitaxel or camptothecin. MCF-7 cells showed and maintained a colony formation when cultured on the COL-I- and Matrigel-coated dish. Moreover, cytotoxicity (IC50) was decreased by taxol (paclitaxel) or camptothecin treatment during colony formation in MCF-7 cells, suggesting that morphological changes could increase survival of cells treated with anticancer drugs. Thick circumferential bundles of microtubules around the periphery of the cells and chromatin condensation was not observed for MCF-7 cells on COL-I- and Matrigel-coated dishes treated with paclitaxel. To confirm this, spheroid cells were prepared, and we found that cytotoxicity was decreased for these cells, and significantly increased when cells were co-cultured on Matrigel- or COL-I-coated upper wells. The effect of anticancer drugs on cell survival was efficiently inhibited by interleukin-6 (IL-6) and interleukin-8 (IL-8).
Present results suggested that not only integrin-ECM interactions but also other factors such as IL-6and IL-8secreted by cancer cells, cultured on COL-I and Matrigel dishes, are involved in the acquisition of drug resistance by MCF-7.
研究细胞外基质(ECM)的各种成分对乳腺癌细胞系MCF-7获得对紫杉醇和喜树碱耐药性的影响。
将癌细胞培养在牛血清白蛋白(BSA)、玻连蛋白(VN)、纤连蛋白(FN)、I型胶原(COL-I)或基质胶包被的培养板上,进行或不进行紫杉醇或喜树碱处理。通过XTT法评估抗癌药物对细胞生长的影响,并用相差显微镜检查细胞形态的改变。使用抗β-微管蛋白单克隆抗体进行免疫荧光研究。
当用不含ECM成分的抗癌药物处理时,所有细胞系的细胞存活率均显著降低,而在用紫杉醇或喜树碱处理后,将细胞培养在COL-I和基质胶包被的培养皿上时,Caco-2、MCF-7和NCI-H292的存活率显著提高。MCF-7细胞在COL-I和基质胶包被的培养皿上培养时表现出并维持了集落形成。此外,在MCF-7细胞集落形成过程中,紫杉醇或喜树碱处理可降低细胞毒性(IC50),表明形态学改变可增加用抗癌药物处理的细胞的存活率。在用紫杉醇处理的COL-I和基质胶包被的培养皿上,未观察到MCF-7细胞周围有厚的周向微管束和染色质浓缩。为证实这一点,制备了球体细胞,我们发现这些细胞的细胞毒性降低,而当细胞在基质胶或COL-I包被的上室共培养时,细胞毒性显著增加。白细胞介素-6(IL-6)和白细胞介素-8(IL-8)可有效抑制抗癌药物对细胞存活的影响。
目前的结果表明,不仅整合素-ECM相互作用,而且癌细胞分泌的其他因子如IL-6和IL-8,在COL-I和基质胶培养皿上培养时,都参与了MCF-7耐药性的获得。