Correlation between chemosensitivity to anticancer drugs and Bcl-2 expression in gastric cancer

Objective: To investigate chemoresistance of human gastric cancer to chemotherapeutic drugs in vitro and explore the relationship with Bcl-2 protein expression. Methods: Single-cell suspensions were prepared from freshly excised samples of primary gastric cancer, and were separately exposed to taxol (TAX), cisplatin (CDDP), 5-fluorouracil (5-FU), adriamycin (ADM) and mitomycin (MMC) for 48 h. The induction of cell death was confirmed by microscopic analysis of cell morphology. Metabolic activity and the inhibitory rate (IR) of cells were evaluated by MTT assay. Expression of Bcl-2 was determined by immunohistochemistry of gastric cancer tissue samples. Results: The IRs of cancer cells exposed to different chemotherapeutic drugs varied as follows: the IRs for TAX, CDDP and 5-FU were significantly higher than those for ADM and MMC (P < 0.01). Poorly differentiated gastric cancer cells were more sensitive than well-differentiated cells (P = 0.021). The positive rate of Bcl-2 expression was 80%, and Bcl-2 expression was significantly associated with chemoresistance to 5-FU (r_s = 0.265, P = 0.041), ADM (r_s = 0.425, P = 0.001) and MMC (r_s = 0.40, P = 0.002). Furthermore, Bcl-2 expression was strongly associated with lymph node metastasis in gastric cancer (P = 0.009). Conclusion: Overexpression of Bcl-2 may predict a loss of the efficacy of the chemotherapy drugs 5-FU, ADM and MMC in patients with gastric cancer.     

胃癌多药耐药细胞株BGC823/5-FU的建立及其耐药机制的研究

目的：建立5-氟尿嘧啶（5-FU）诱导的胃癌多药耐药细胞株BGC823/5-FU，探讨凋亡相关蛋白Survivin、Bcl-2、Bax及caspase-3与其耐药性产生的关系。 方法:采用反复短期暴露并逐渐增加5-FU浓度的方法建立胃癌耐药细胞株BGC823/5-FU，MTT法检测此耐药细胞株对5-FU的耐药倍数及其对临床常用化疗药物阿霉素、丝裂霉素和顺铂的交叉耐药性，流式细胞术检测细胞P-糖蛋白的表达和柔红霉素积累量；Western blotting法检测耐药胃癌细胞株BGC823/5-FU与其亲代药物敏感胃癌细胞株BGC823凋亡相关蛋白Survivin、Bcl-2、Bax及caspase-3的表达。 结果:成功诱导出胃癌多药耐药细胞株BGC823/5-FU，较其亲代细胞BGC823对5-FU、阿霉素、丝裂霉素和顺铂的耐药性分别提高10.82、2.50、22.23和2.00倍。其P-糖蛋白表达较BGC823细胞增高（P<0.01），柔红霉素积累量较BGC823细胞减低（P<0.01）。与亲代药物敏感BGC823细胞相比，耐药细胞株BGC823/5-FU细胞Survivin表达上升（P<0.05），Bcl-2表达升高（P<0.05），Bax表达下降（P<0.05），caspase-3表达减低（P<0.05）。结论:胃癌细胞株BGC823在5-FU的诱导下可形成多药耐药细胞株BGC823/5-FU，P-糖蛋白、凋亡相关蛋白Survivin、Bcl-2、Bax及caspase-3可能参与其耐药性的形成。     

不同化疗药物对结肠癌细胞获得性TRAIL基因耐药的逆转作用

目的：探讨不同化疗药物对结肠癌DLD1细胞获得性TRAIL基因耐药的逆转作用及其可能的机制。 方法：将不同化疗药物联合重组腺病毒载体（Ad）介导的TRAIL基因处理对Ad/gTRAIL耐药的结肠癌DLD1-TRAIL/R细胞，通过MTT法检测治疗后肿瘤细胞的存活率，以评价化疗药物对TRAIL基因耐药的逆转作用；然后进一步在体内评价该逆转策略的有效性；接着通过Western免疫印迹等方法探讨逆转耐药的可能机制。结果：在体外检测了5-氟脲嘧啶、丝裂霉素、阿霉素、氟脲苷、依立替康以及顺铂6种化疗药物对DLD1-TRAIL/R细胞TRAIL基因耐药的逆转作用，结果发现只有5-氟脲嘧啶和丝裂霉素能够使DLD1-TRAIL/R细胞对Ad/gTRAIL重新敏感。进一步的结果表明联合5-氟脲嘧啶和Ad/gTRAIL能在体内有效地抑制DLD1-TRAIL/R细胞来源的肿瘤生长，且该抑制作用明显强于其它对照组。结论：联合使用Ad/gTRAIL和5-氟脲嘧啶或丝裂霉素能在体内外有效地逆转DLD1-TRAIL/R细胞对TRAIL基因的获得性耐药，其中丝裂霉素的逆转作用可能与其诱导的Bax过度表达有关。     

二氢青蒿素通过抑制SIRT1的表达而增强5-氟尿嘧啶对胃癌的抗肿瘤活性

目的:探讨二氢青蒿素对5-氟尿嘧啶治疗胃癌的辅助作用并研究其机制。方法:实验分为对照组、二氢青蒿素组、5-氟尿嘧啶组、5-氟尿嘧啶联合二氢青蒿素组和5-氟尿嘧啶+二氢青蒿素+SIRT1质粒组。MTT法检测胃癌细胞系BGC-823在5-氟尿嘧啶联合二氢青蒿素处理下的细胞活力。Western blot实验检测5-氟尿嘧啶联合二氢青蒿素对BGC-823细胞SIRT1和NADPH氧化酶表达水平,caspase-9和caspase-3活化水平及凋亡信号调节激酶1(ASK1)和c-Jun氨基末端激酶(JNK)蛋白磷酸化水平的影响。流式细胞术检测BGC-823细胞在5-氟尿嘧啶和二氢青蒿素联合处理下的活性氧簇(ROS)生成水平和细胞凋亡率。结果:二氢青蒿素处理能显著抑制BGC-823细胞SIRT1的表达并增加NADPH氧化酶的蛋白水平,明显提高BGC-823细胞对5-氟尿嘧啶的敏感性,降低5-氟尿嘧啶的半数抑制浓度;转染SIRT1表达质粒后,二氢青蒿素联合5-氟尿嘧啶对BGC-823细胞的杀伤活性受到显著抑制(P0.05)。二氢青蒿素能明显促进5-氟尿嘧啶对BGC-823细胞生成ROS的诱导效应和ASK1及JNK的磷酸化(P0.05)。用ROS清除剂N-乙酰半胱氨酸(NAC)或JNK特异性抑制剂SP600125处理后,二氢青蒿素联合5-氟尿嘧啶对BGC-823细胞的杀伤活性和caspase-9及caspase-3的活化均受到明显抑制(P0.05)。另外,NAC能显著抑制二氢青蒿素联合5-氟尿嘧啶对JNK磷酸化的促进作用,而SP600125却不能影响BGC-823细胞ROS的产生,表明JNK是ROS的下游分子。结论:二氢青蒿素联合5-氟尿嘧啶通过SIRT1/NADPH氧化酶/ROS/JNK通路诱导胃癌细胞发生caspase依赖的凋亡。     

紫苏醇对肺癌A549 细胞增殖和侵袭的抑制作用机制的研究

目的:探讨紫苏醇(Perillyl alcohol,PA)对肺癌A549 细胞增殖和侵袭的抑制作用机制,并阐明其对肿瘤血管生成信号的影响。方法:不同浓度PA 和厄洛替尼加入到A549 细胞中,利用溴化3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑(MTT)法测定药物组对A549 细胞的抑制作用,Transwell 法检测PA 对A549 细胞侵袭的抑制作用,采用间接荧光标记法测定细胞内活性氧(ROS)水平的变化;分光光度法检测PA 对细胞凋亡蛋白Caspase-3 活性的影响,Western blot 法检测A549 中VEGF、HIF-1 及COX-2 的表达,凝胶迁移或电泳迁移率实验测定A549 细胞中NF-κB 活性。结果:与空白对照组比较,随着浓度的增加(10、50、100 g/ ml),PA 和厄洛替尼对A549 细胞生长的抑制率在不断地增加,差异均有统计学意义(P<0.05),A549 细胞侵袭能力呈现不断下降的趋势,差异均有统计学意义(P<0.05),A549 细胞内活性氧水平随厄洛替尼浓度的增加变化不大,而ROS 水平随着PA 的浓度的增加而增加,在100 g/ ml 浓度的PA 下引起的ROS 百分率达到了(80.43±6.92)%,差异均有统计学意义(P<0.05)。细胞活力检测结果显示,随着PA 和厄洛替尼浓度的增加和作用时间的延长,A549 细胞中凋亡蛋白Caspase-3 活性明显增加(P<0.05),随着紫苏醇浓度的增加,COX-2、VEGF 和HIF-1 的表达呈不断降低的趋势,EMSA 检测结果显示,随着PA 浓度的增加,NF-κB 的条带面积不断减少。结论:PA 可能参与并促进了ROS 的生成和Caspase-3 活性增加,最终诱导A549 细胞的凋亡,PA 可能通过降低NF-κB 的表达,进而诱导COX-2、VEGF 等的表达减少,使血管生成滞后,能够有效地使细胞的穿透能力下降和凋亡发生。     

Methylation of PRDM2, PRDM5 and PRDM16 genes in lung cancer cells

Aims: To investigate the changes of expression and methylation status of PRDM2, PRDM5, PRDM16 in lung cancer cells after treatment with demethylation agent. Methods: A549 (lung adenocarcinoma cell line), HTB-182 (lung squamous cell carcinoma cell line) and HBE (normal bronchial cell line) were treated with 5-aza-2dC. The methylation state of PRDM2, PRDM5, PRDM16 was detected by MSP. The expression of PRDM2, PRDM5, PRDM16 was detected by RT-PCR and Western blot analysis. Cell growth was detected by MTT assay. Results: 5-aza-2-dC reduced the methylation of PRDM2, PRDM5, PRDM16 gene in A549 and HTB-182 cells but not in HBE cells. Consistently, 5-aza-2dC increased mRNA and protein expression of PRDM2, PRDM5, PRDM16 in A549 and HTB-182 cells but not in HBE cells. Furthermore, 5-aza-2dC inhibited the growth of A549 and HTB-182 cells but not HBE cells. Conclusions: PRDM2, PRDM5, PRDM16 promoters are methylated and their expression is suppressed in lung cancer cells. Demethylation drug 5-aza-2dC could upregulate the expression of PRDM2, PRDM5, PRDM16 and suppress lung cancer cell growth. 5-aza-2dC has potential to be used for lung cancer therapy by epigenetic mechanism.     

Induction of ROS, mitochondrial damage and autophagy in lung epithelial cancer cells by iron oxide nanoparticles

Autophagy has attracted a great deal of research interest in tumor therapy in recent years. An attempt was made in this direction and now we report that iron oxide NPs synthesized by us selectively induce autophagy in cancer cells (A549) and not in normal cells (IMR-90). It was also noteworthy that autophagy correlated with ROS production as well as mitochondrial damage. Protection of NAC against ROS clearly suggested the implication of ROS in hyper-activation of autophagy and cell death. Pre-treatment of cancer cells with 3-MA also exhibited protection against autophagy and promote cellular viability. Results also showed involvement of classical mTOR pathway in autophagy induction by iron oxide NPs in A549 cells. Our results had shown that bare iron oxide NPs are significantly cytotoxic to human cancer cells (A549) but not to the normal human lung fibroblast cells (IMR-90).In other words our nanoparticles selectively kill cancerous cells. It is encouraging to conclude that iron oxide NPs bear the potential of its applications in biomedicine, such as tumor therapy specifically by inducing autophagy mediated cell death of cancer cells.     

Short-term Morphological response of the rat testis to administration of five chemotherapeutic agents

As cancer survival rates improve, there is increasing concern about the adverse effects of chemotherapeutic agents on male fertility. Five chemotherapeutic agents (amethop-terin, AP or methotrexate; doxorubicin, DX; cytoxan or cyclophosphamide, CP; cisplatinum, CDDP; and 5-fluorouracil, 5-FU) which belong to three different categories of chemotherapeutic agents (antimetabolite, antibiotic, alkylating agent, alkylating agent, antimetabolite, respectively) were given systemically to adult rats to determine the short-term morphological patterns of response in the testis, and the testes were examined by light microscopy. Morphological patterns of response were found to be highly characteristic for each agent, and some shared morphological responses were evident. All except one chemotherapeutic agent (5-FU) caused spermatogonial damage. Among the defects seen were probable degenerating meiotic spermatocytes (CDDP), presence of micronuclei (DX), “arrested” spermatid development (5-FU), and abnormally shaped step 15 spermatids (5-FU). Damage that could be due to the effect of an agent on the Sertoli cell was failure of sperm release (5-FU, CDDP, DX, and AP), increase in the Sertoli cell lipid (5-FU), and malorientation of step 8 spermatids (5-FU, DX). The varied patterns of damage observed are a possible explanation of why the reproductive recovery potential in cancer patients undergoing chemotherapy is variable and drug-specific.     

科罗索酸通过抑制Hippo-YAP信号转导通路促进非小细胞肺癌细胞的凋亡

目的：研究科罗索酸对肺癌细胞增殖与凋亡的影响及其机制。方法：MTT、Caspase3/7活性检测、Western blot等方法检测不同浓度的科罗索酸是否影响肺癌细胞株A549的增殖和凋亡;Western blot、免疫荧光实验等方法检测科罗索酸对肺癌细胞A549 Hippo通路中YAP蛋白进行定量和定位的检测。结果：MTT结果显示科罗索酸能够抑制肺癌细胞株A549的增殖,半抑制浓度为40 μmol/L;Caspase活性检测结果显示科罗索酸能够促进肺癌细胞株A549的凋亡,半致死浓度为40 μmol/L;Western blot、免疫荧光试验结果显示科罗索酸能明显抑制肺癌细胞株A549中YAP蛋白的表达。结论：科罗索酸可能通过调控Hippo-YAP信号通路抑制肺癌细胞的增殖并促进其凋亡。     

促性腺激素释放激素类似物对乳腺癌细胞株化疗敏感性的影响

目的： 探讨促性腺激素释放激素类似物（GnRHa）对乳腺癌细胞株（MCF-7和MDA-MB-231）化疗敏感性的影响。方法：不同浓度的GnRHa（曲普瑞林,triptorelin）（10^－9 mol/L、10^－8 mol/L、10^－7 mol/L、10^－6 mol/L、10－5 mol/L）分别作用于MCF-7和MDA-MB-231细胞24 h、96 h和168 h后，用CCK-8方法检测细胞活性。用或不用GnRHa（10^－5 mol/L）处理96 h后，分别加入5-氟尿嘧啶（5-FU）或表阿霉素(EPI)作用24 h，用CCK-8法检测细胞抑制率。用RT-PCR检测GnRHa（10^－5 mol/L）作用168 h后GnRH受体、PCNA和MDR1 mRNA表达水平。结果：不同浓度GnRHa作用不同的时间后对乳腺癌细胞活性无影响。GnRHa（10^－5 mol/L）作用96 h后，5－FU和EPI对两种细胞的IC50不改变；GnRHa（10^－5 mol/L）不影响5－FU（MCF-7细胞0.5 g/L，MDA－MB－231细胞0.5 g/L）和EPI（MCF-7细胞1.2 mg/L,MDA－MB－231细胞0.8 mg/L）对两种细胞的抑制作用（P>0.05）。GnRHa（10^－5 mol/L）作用168 h后，MCF-7细胞的PCNA mRNA表达无改变。而在MDA-MB-231细胞，PCNA表达升高，差别有统计学意义（P<0.05）。在MCF-7对照组中，MDR1 mRNA有弱表达。GnRHa作用后，抑制了MDR1 mRNA表达。MDA-MB-231细胞GnRHa作用前后， MDR1 mRNA均无表达。结论：GnRHa不影响乳腺癌细胞株对5-FU和EPI的敏感性。GnRHa可能通过下调MDR1 mRNA表达水平，减弱MCF-7细胞的耐药性。     

过表达miR-10b促进肺癌细胞系A549增殖

目的探讨非小细胞肺癌(NSCLC)患者肺癌及癌旁组织中miR-10b(miR-10b)表达水平及miR-10b是否通过调控锌指转录蛋白基因(KLF4)对肺癌细胞系A549恶性化的影响。方法 40例NSCLC患者病理切片,原位杂交检测肺癌及癌旁组织中miR-10b的表达量;对肺癌细胞系A549转染miR-10b mimics后,CCK-8法检测肺癌细胞增殖;real-time PCR及Western blot检测KLF4 mRNA及蛋白水平;软琼脂克隆形成实验检测过表达miR-10b对A549细胞的肿瘤恶性化程度的影响。结果肺癌细胞A549及肺癌组织中miR-10b的表达量分别高于正常肺上皮细胞16HBE及癌旁组织;过表达miR-10b模拟物的A549细胞中,KLF4蛋白水平显著下降(P0.05);过表达的miR-10b可显著增加A549细胞的增殖速度及在软琼脂内的成瘤性。结论 miR-10b在不同类型细胞及组织中具有分布差异性、可能是通过抑制KLF4的表达促进肺癌细胞增殖及恶性化。     

Update in cancer chemotherapy, Part III: Lung cancer, Part 1

An update in cancer chemotherapy that deals with the various therapies of lung cancer is described. At present, the stage of the disease and cell type are the major factors that determine the treatment. Important differences in the biological behavior and response to treatment exist between small cell and non-small cell cancers. The small cell type is sensitive to many chemotherapeutic agents. Differences in response to chemotherapy and survival have been less among the non-small cell types.     

Co-delivery of paclitaxel and survivin shRNA by pluronic P85-PEI/TPGS complex nanoparticles to overcome drug resistance in lung cancer

Drug resistance is a main obstacle for the successful chemotherapy of lung cancer. In this work, a new co-delivery system, P85-PEI/TPGS/PTX/shSur complex nanoparticles (PTPNs), to overcome paclitaxel (PTX) resistance in A549 human lung cancer was designed and developed. The experimental results showed that PTPNs could facilitate drug into cells and induce survivin shRNA (shSur) into nuclei on A549 and A549/T cells, achieve efficient gene delivery and induce availably RNA interference on A549/T cells. The IC(50) of PTPNs against A549/T cells was 360-fold lower than that of free PTX. The enhanced efficacy of PTPNs against A549/T cells was associated with PTX-induced apoptosis and cell arrest in G2/M phase. Down-regulation of survivin protein by PTPNs could lower the apoptosis threshold of drug resistant cells and render chemotherapeutic agents more effective. Moreover, the inhibition of GST activity by P85 was found to increase PTX accumulation in A549/T cells. The in?vivo antitumor efficacy showed that PTPNs were more effective than that of the Taxol. As a result, the co-delivery of PTX and shSur by PTPNs could be a very powerful approach to improve the therapeutic effect of PTX in resistant lung cancer.     

长链非编码MALAT-1 调控miR-205 的表达影响非小细胞肺癌细胞的生长和迁移

目的:探讨在非小细胞肺癌中,LncRNA MALAT-1 与miR-205 的相互关系,以及影响肺癌细胞生物学行为的机制。方法:qPCR 检测不同非小细胞肺癌中LncRNA MALAT-1 的表达情况;双荧光素酶报告基因检测MALAT-1 与miR-205的相互作用;Transwell 侵袭实验和划痕实验检测抑制MALAT-1 后肺癌细胞侵袭能力的变化,以及抑制miR-205 的表达后肺癌细胞迁移和侵袭能力的恢复情况;裸鼠皮下成瘤检测抑制LncRNA MALAT-1 后肺癌细胞体外成瘤体积和质量变化。结果:与其他肺癌细胞株相比,A549 细胞中MALAT-1 表达最高,miR-205 的表达水平最低;双荧光素酶实验证实MALAT-1 能与miR-205 的3忆UTR 特异性结合,可以调控miR-205 的表达与活性;抑制MALAT-1 的表达后可以降低肺癌细胞的迁移和侵袭能力;抑制miR-205 的表达水平过后,肺癌细胞的迁移和侵袭能力相对增强;抑制MALAT-1 的表达后,荷瘤小鼠的肿瘤体积和重量都明显减小。结论:MALAT-1 可以调控miR-205 的表达影响肺癌细胞A549 的侵袭和迁移能力。     

Update in cancer chemotherapy, Part IV. Lung cancer, Part 2

An update of cancer chemotherapy in 1985 that deals with the various therapies of lung cancer is described. At present, the stage of the disease and cell type are the major factors that determine the treatment. Important differences in the biological behavior and response to treatment exist between small cell and non-small cell cancers. Treatment of the small cell type, which is sensitive to many of the cancer chemotherapeutic agents, is discussed in this paper. Treatment of the non-small cell types was described in the October issue of the Journal.     

MicroRNA-145通过丝裂原活化蛋白激酶和磷脂酰肌醇3激酶/蛋白质丝氨酸苏氨酸激酶通路调控肺癌A549细胞系转移及侵袭

目的 探讨microRNA-145(miR-145)对非小细胞肺癌A549细胞转移、侵袭及对丝裂原活化蛋白激酶(MAPK)和磷脂酰肌醇3激酶/蛋白质丝氨酸苏氨酸激酶（PI3K/AKT）通路的作用。 方法 将非小细胞肺癌A549细胞分成miR-145模拟物（mimics）组和negative-mimics组（miR-NC）以及antago miR-145组（抑制剂组）和antago miR control 组（antago-NC）,采用Transwell迁移实验及基质胶侵袭实验等检测miR-145对人非小细胞肺癌A549迁移、侵袭能力的影响;Western blotting方法分析miR-145对MAPK和PI3K/AKT通路的影响。此外,采用细胞外调节蛋白激酶（ERK）及AKT的通路抑制剂分别作用于A549细胞系,检测A549细胞迁移、侵袭能力的改变。 结果 miR-145 mimics组穿过细胞数（90.67±10.33）明显少于miR-NC组（175.33±23.67）,miR-145 mimics组穿过基质胶的细胞数（153.33±22.33）少于miR-NC组 (77.33±13.67）,P<0.05;antago-NC组通过小室的细胞数量以及穿过基质胶的细胞数量明显少于antago miR-145组（P<0.05）,结果说明,miR-145具有抑制非小细胞肺癌A549细胞迁移、侵袭的能力;miR-145 mimics转染可分别抑制A549细胞中90%、78%以及73%的ERK1/2、AKT的ser-473位点和thr-308位点的磷酸化,antago miR-145转染可促进A549细胞中ERK1/2、AKT的ser-473位点和thr-308位点的磷酸化,增加115%、125%以及129%,而当抑制MAPK通路及PI3K/AKT通路的激活后,A549细胞的转移及侵袭能力下降。 结论 miR-145通过MAPK和PI3K/AKT通路调控肺癌A549细胞转移及侵袭。     

Camptothecin induces urokinase-type plasminogen activator gene-expression in human RC-K8 malignant lymphoma and H69 small cell lung cancer cells

We previously reported that anthracyclines, which could generate reactive oxygen species (ROS), could induce the urokinase-type plasminogen activator (uPA) gene expression in human RC-K8 malignant lymphoma cells and in H69 small cell lung cancer (SCLC) cells. In screening other uPA-inducible anti-cancer agents, we found that camptothecin (CPT) and its derivative, SN38, could induce uPA in RC-K8 and H69 cells. CPT and SN38, which are also used for the treatment of lymphoma and SCLC, significantly increased the uPA accumulation in the conditioned media of both cells in a dose-dependent manner. The maximum induction of uPA mRNA levels was observed 24 h after stimulation. Pretreatment with pyrrolidine dithiocarbamate (PDTC), an anti-oxidant, inhibited the CPT-induced uPA mRNA expression. Thus, CPT induces uPA through gene expression, and, therefore, CPT may influence the tumor-cell biology by up-regulating the uPA/plasmin system.     

不同人结直肠肿瘤细胞系对常用抗肿瘤药物体外化疗敏感性的比较

 目的：观察5种常用抗肿瘤药物对这些人结直肠肿瘤细胞系的生长抑制作用,探讨5种常用抗肿瘤药物对11株人结直肠肿瘤细胞系的作用强度以及比较其体外敏感性,研究不同抗肿瘤药物对人结直肠癌细胞系HCT116和SW480热休克蛋白27（HSP27）和HSP70表达水平的影响。方法：采用CCK-8（Cell Counting Kit-8）法检测5种常用抗肿瘤药物分别对11株人结直肠肿瘤细胞系的生长抑制效应,计算50%抑制浓度（50% inhibitory concentration, IC50）及敏感指数,并比较不同人结直肠肿瘤细胞系对5种抗肿瘤药物的敏感性,Western blotting检测HSP27和HSP70蛋白表达水平。结果：11株人结直肠肿瘤细胞系对5-氟尿嘧啶(5-FU)和奥沙利铂(OHP)均比较敏感,没有明显耐药性;5株人结直肠肿瘤细胞系对丝裂霉素(MMC)敏感,6株中度敏感;除SW1116 外的10株人结直肠肿瘤细胞系都对多西紫杉醇(DXL)敏感,而SW1116细胞对DXL表现出明显耐药性;除LS174T和SW1116外的9株人结直肠肿瘤细胞系都对伊立替康(IFL)表现出中度敏感,LS174T细胞对IFL表现敏感,而SW1116细胞对IFL表现出明显耐药性。抗肿瘤药物作用于人结直肠癌细胞系HCT116和SW480使HSP27的表达上调,但HSP70的表达水平变化不明显。结论：LS174T是多药敏感细胞株,SW1116是多药耐药细胞株,5-FU和OHP为广谱抗结直肠肿瘤药物;化疗药物的敏感性及HSP27表达量检测对临床选择化疗药物具有一定的提示意义。     

2-甲氧雌二醇对人肺癌细胞的放射增敏作用

目的:探讨2-甲氧雌二醇(2-ME)对肺癌细胞A549和GLC-82的放射增敏作用及其对细胞周期的影响,并从分子角度初步探讨2-ME可能的增敏机制。方法:将体外培养的人肺癌细胞A549和GLC-82分为实验组和对照组,其中实验组加入不同浓度的2-ME,对照组不含2-ME。通过MTT法定量检测2-ME对2株细胞增殖的抑制作用,集落形成实验测定2-ME对这2株细胞的放射增敏作用,流式细胞术检测细胞周期分布的变化,通过免疫沉淀法检测细胞周期素依赖性蛋白激酶2(CDK2)活性的改变。结果:分别以2-ME对人肺癌细胞GLC-82和A549的最小有效浓度(0.15625×10-6mol/L和1.25×10-6mol/L)作为放射增敏浓度,均可增加细胞对X线的敏感性,2株细胞存活曲线均见2-ME增敏组比单纯照射组整体下移,D0、Dq值均降低,增敏比:GLC-82细胞为1.98;A549细胞为2.06。细胞周期的检测表明2-ME使细胞周期阻滞于G2/M期,并呈剂量依赖性。2-ME作用后2株细胞CDK2活性均无明显改变。结论:2-ME可通过对细胞周期的调节增加非小细胞肺癌(NSCLC)细胞GLC-82和A549对射线的敏感性。