卵巢癌对顺铂耐药机制的研究进展

卵巢癌的发病率在女性生殖器恶性肿瘤中占第三位，但其患者死亡率却居首位。在细胞减灭术的基础上施以以顺铂为主的联合化疗方案已成为卵巢癌的常规治疗方案。据报道：Ⅲ和Ⅳ期的卵巢癌患者采用联合化疗．其完全缓解率可达60％-80％。但在实际临床应用中却并非如此。近30年来卵巢癌患者的5年生存率一直徘徊于30％-50％之间。其主要原因就是卵巢癌对化疗药物产生了耐爱性。约75％-80％的卵巢上皮癌开始对化疗有反应．其余则表现为原发耐药．最终所有化疗患者至少80％出现耐药。因此，耐药的产生直接影响化疗效果及生存率。如何尽早发现耐药度克服耐药是急需解决的问题。     

卵巢癌顺铂耐药性研究进展

卵巢癌顺铂耐药是困扰广大学者的难题，近年来研究发现除细胞内药物蓄积和DNA伤修复以外，基因和凋亡调控因子的变化在其中亦起着重要作用。同时细胞外基质、热休克蛋白等相关因素的发现也为人们提供了新思路。现综述上述领域以及耐药逆转方面的研究成果。     

不同糖浓度下顺铂联合雷帕霉素对子宫内膜癌细胞增殖的体外研究

目的 观察在不同糖浓度下顺铂联合mTOR抑制剂雷帕霉素对子宫内膜癌(EC)细胞增殖、周期和凋亡的影响,进一步研究Akt/mTOR/S6信号通路相关蛋白表达的改变.方法 模拟人体血糖浓度(高糖浓度组25 mmol/L,正常糖浓度组11 mmol/L)体外培养人EC Ishikawa和HEC-1B细胞.细胞计数盒8(CCK...     

hMS H2重组质粒对人卵巢癌细胞顺铂敏感性的影响

目的：研究hMSH2重组质粒对卵巢癌顺铂敏感性方面的影响。方法：构建重组真核表达质粒pCAN－hMSH2,通过酶切及测序法对重组质粒进行鉴定。采用脂质体转染技术对卵巢癌耐药细胞SKOV3／DDP进行瞬时转染,对照组为未转染细胞和SKOV3敏感细胞;hMSH2在细胞内的表达变化由Western blotting和RT－PCR进行检测;四甲基偶氮唑蓝（MTT）法对细胞的顺铂敏感性进行检测;耐药细胞的凋亡情况通过Hoechst染色法检测。结果：重组质粒pCAN－hMSH2转染进SKOV3／DDP后,经RT－PCR和Western blotting检测证实转染成功,hMSH2的表达得到增强;MTT结果提示转染后的卵巢癌耐药细胞对顺铂的敏感性明显增强;Ho-echst染色发现,转染后耐药细胞的凋亡明显增强。结论：hMSH2基因转染后能提高其在SKOV3／DDP细胞中的表达,增强SKOV3／DDP细胞对顺铂的敏感性,促进在顺铂作用下的凋亡。     

PAFR对卵巢癌细胞顺铂敏感性的影响及机制研究

背景与目的：目前卵巢癌的治疗方式仍是手术及术后辅助铂类药物为主的化疗,但复发率高,容易耐药。前期研究已证实血小板活化因子受体（platelet-activating factor receptor,PAFR）在上皮性卵巢癌中高表达,且能促进卵巢癌细胞增殖、侵袭及转移。探索顺铂（cisplatin,CDDP）作用后卵巢癌细胞中PAFR的表达变化及其对卵巢癌细胞CDDP敏感性的影响,并对其机制进行初步探讨,旨在为卵巢癌靶向治疗及克服CDDP耐药提供新方法。方法：采用蛋白质印迹法（Western blot）及实时荧光定量聚合酶链反应（real-time fluorescence quantitative polymerase chain reaction,RTFQ-PCR）检测不同浓度的CDDP作用于卵巢癌细胞株（SKOV-3和CAOV-3）不同时间后各组细胞PAFR的表达情况。采用Western blot及免疫荧光法验证CDDP作用于卵巢癌细胞后核因子κB（nuclear factor Kappa-B,NF-κB）/p65及缺氧诱导因子-1α（hypoxia inducible factor-1α,HIF-1α）的表达。采用Western blot及RTFQ-PCR检测小RNA干扰沉默NF-κB及HIF-1α后PAFR的表达情况。采用细胞增殖和凋亡实验检测抑制PAFR表达后对卵巢癌细胞CDDP敏感性的影响。采用Western blot验证CDDP和（或）PAFR抑制剂作用细胞后下游信号通路关键分子P70S6K/AKT/ERK的变化情况。结果：CDDP能够引起卵巢癌细胞中PAFR表达升高,并呈现剂量及时间依赖性（P＜0.01）。CDDP能够引起转录因子NF-κB及HIF-1α的核聚集,沉默NF-κB及HIF-1α后,CDDP诱导的PAFR表达下降。PAFR特异性小分子拮抗剂WEB2086或RNA干扰抑制PAFR表达均能显著提高卵巢癌细胞对于CDDP的敏感性,即细胞增殖能力明显降低（P＜0.01）,而凋亡率明显升高（P＜0.01）。CDDP作用于卵巢癌细胞后,表达升高的PAFR能够激活下游的AKT及ERK信号通路分子。结论：CDDP作用于卵巢癌细胞后能够引起转录因子NF-κB及HIF-1α的核聚集从而上调PAFR的表达。抑制PAFR表达能够增加卵巢癌细胞对CDDP的敏感性,可能成为卵巢癌靶向治疗的新方法。     

反义LRP寡核苷酸对卵巢癌多药耐药细胞系OVCAR-3顺铂耐药性的影响

目的:探讨针对肺耐药基因(LRP gene)设计的反义寡核苷酸(AsODN)对人卵巢癌多药耐药细胞系OVCAR-3顺铂(DDP)耐药性的逆转作用.方法:采用罗丹明B(SRB)显色法检测LRP AsODN和DDP细胞毒性作用;采用脂质体(1iplfectamine 2000)介导LRP AsODN转染人卵巢癌多药耐药细胞系OVCAR-3;采用逆转录酶链式反应(RT-PCR)和Westem blot法检测LRP AsODN转染前后OVCAR-3细胞中LRP的表达:采用流式细胞仪测定OVCAR-3细胞在顺铂作用后的凋亡率.结果:LRP AsODN浓度低于800nmol/L时,对OVCAR-3细胞无明显细胞毒作用;LRP AsODN能明显减少OVCAR-3细胞中LRP mRNA和蛋白的表达,增加其顺铂敏感性,且与剂量呈正相关;转染LRP AsODN前后的OVCAR-3细胞在DDP作用后,凋亡率分别为(15.43±1.14)%和(27.43±2.05)%,两者间差异有显著性意义(p=0.001).结论:LRP AsODN能有效阻断OVCAR-3细胞内LRP的表达,恢复细胞对DDP的敏感性.     

舒林酸对卵巢癌细胞系CP70顺铂耐药性的逆转作用

目的:研究舒林酸体外逆转卵巢癌细胞系CP70的顺铂耐药性,并探讨其与β-catenin表达的关系。方法:MTT法检测单独使用舒林酸或顺铂及两药联合使用时对CP70细胞的抑制作用,免疫细胞化学和Western blot方法检测细胞内β-catenin表达水平。结果:两药联合处理细胞后顺铂耐药逆转倍数为6.01,联合处理组的细胞中β-catenin表达明显降低。结论:舒林酸能部分逆转CP70细胞对顺铂的耐药性,且此作用可能与下调细胞的β-catenin表达有关。     

舒林酸对卵巢癌细胞系CP70顺铂耐药性的逆转作用

目的：研究舒林酸体外逆转卵巢癌细胞系CP70的顺铂耐药性，并探讨其与β—catenin表达的关系。方法：MTT法检测单独使用舒林酸或顺铂及两药联合使用时对CP70细胞的抑制作用，免疫细胞化学和Westernblot方法检测细胞内β—catenin表达水平。结果：两药联合处理细胞后顺铂耐药逆转倍数为6．01，联合处理组的细胞中β—catenin表达明显降低。结论：舒林酸能部分逆转CP70细胞对顺铂的耐药性，且此作用可能与下调细胞的β—catenin表达有关。     

MFG-E8对卵巢癌SKOV3细胞顺铂敏感度的影响及分子机制

目的 探讨沉默MFG-E8基因对SKOV3细胞抗癌药物敏感度的影响及其相关机制.方法 小干扰技术沉默卵巢癌SKOV3细胞中MFG-E8基因并对干扰效率进行测定.CCK-8检测转染MFG-E8 siRNA后SKOV3细胞对顺铂的敏感度.qRT-PCR检测MFG-E8基因沉默后多重耐药蛋白ABCB1及ABCC1 mRNA的...     

小剂量顺铂治疗晚期卵巢癌

 本组自1975年应用小剂量多疗程顺铂治疗Ⅲ、Ⅳ期卵巢癌截止1985年底共46例。单用顺铂21例;以顺铂为基础的联合化疗25例:寿命表法计算46例晚期癌3、4和5年存活率为45.4%、41.9%和35.4%。毒副反应轻微,未曾发生严重肾毒和神经毒性。本文还就小剂量顺铂对机体免疫功能影响进行了探讨。     

Dacomitinib improves chemosensitivity of cisplatin-resistant human ovarian cancer cells

Drug resistance hinders effectiveness of human ovarian cancer (OC) therapies, such as cisplatin or paclitaxel therapy. Although dacomitinib, a novel anticancer agent is used against multiple types of cancers, such as non-small cell lung cancer, head and neck cancer, few studies report its effectiveness in drug-resistant human OC cells. In the present study, would healing, microplate spectrophotometer analysis, flow cytometry analysis, western blotting and Gene Expression Omnibus (GEO) analysis were used to detect the synergistic effect of dacomitinib and cisplatin in human OC SKOV-3 or OV-4 cells. Co-administration of dacomitinib and cisplatin significantly reduced viability and promoted cell apoptosis of drug resistant OC cells. In addition, dacomitinib increased Cadherin 1 (CDH1) levels and decreased P-glycoprotein (P-GP) levels in cisplatin-resistant OC cells. In addition, GEO analysis demonstrated that dacomitinib inhibited the epidermal growth factor receptor (EGFR) signaling pathway. In summary, dacomitinib improves chemosensitivity of cisplatin in human OC by regulating CDH1 and P-GP protein levels and inhibiting the EGFR signaling pathway.     

Inhibition of PI3K/Akt/mTOR signaling pathway enhances the sensitivity of the SKOV3/DDP ovarian cancer cell line to cisplatin in vitro

The activation of the PI3K/AKT/m TOR pathway plays a key role in ovarian cancer tumorigenesis, progression and chemotherapy resistance. This study aimed to explore the possible mechanism that PI-103, a dual inhibitor of phosphatidylinositide 3-kinase and m TOR, enhances the sensitivity of SKOV3/DDP ovarian cancer cell line to cisplatin chemotherapy. The results showed that PI-103 could significantly increase the sensitivity of SKVO3/DDP cells to cisplatin through inhibiting the activation of PI3K/Akt/m TOR signaling pathway and inducing cell cycle arrest and apoptosis.     

Synergistic effect of rapamycin and cisplatin in endometrial cancer cells

BACKGROUND:

Mammalian target of rapamycin (mTOR) inhibitors modulate signaling pathways involved in cell cycle progression, and phase 2 trials for endometrial cancer are currently being conducted. Because rapamycin is known to enhance the cytotoxicity of chemotherapeutic drugs, the authors' goal was to examine the effects of rapamycin and cisplatin in endometrial cancer cell lines.

METHODS:

By using Ishikawa and ECC‐1 cells, cell proliferation was assessed after exposure to rapamycin, cisplatin, or both in combination. The combination index (CI) was calculated using the method of Chou and Talalay. Apoptosis was evaluated by flow cytometry. Immunoblot analysis was performed to assess expression of S6 kinase 1 and the DNA mismatch repair proteins, MSH2 and MSH6. mTOR small interfering (siRNA) was transfected into the cell lines, and proliferation and apoptosis were assessed after exposure to cisplatin.

RESULTS:

Cisplatin inhibited growth in a dose‐dependent manner in both cell lines (median inhibition concentration of 8‐13 μM). Simultaneous exposure of cisplatin in combination with rapamycin resulted in a significant synergistic antiproliferative effect (CI < 1). Rapamycin increased cisplatin‐induced apoptosis and stimulated expression of MSH2 and MSH6 in the cisplatin‐treated cell lines. Cell growth was significantly decreased in cells transfected with mTOR siRNA and treated with cisplatin compared with either alone (CI < 1). Transfection of mTOR siRNA did not induce apoptosis, but combined treatment with cisplatin increased apoptosis over that of cisplatin alone.

CONCLUSIONS:

The results of the current study provide evidence of a synergistic relation between rapamycin and cisplatin in both inhibition of cell growth and induction of apoptosis. This suggests that rapamycin and cisplatin may be a rational combination of a targeted therapy for endometrial cancer. Cancer 2009. © 2009 American Cancer Society.     

维生素C对顺铂治疗大鼠卵巢癌疗效的影响

目的：探讨维生素 C 是否能影响顺铂对于大鼠卵巢癌的化疗效用,并对其作用机制进行初探。方法：建立卵巢癌大鼠模型,将大鼠随机分组后腹腔给药,每周观察一般状况变化。8周后,脱颈处死各组大鼠,取血清检测 CA125、HE4并计算 ROMA 值,测量腹水容积,解剖并观察统计肿瘤生长情况,对局部肿块及主要组织进行测量,常规病理学检查。结果：所有大鼠外观消瘦,体重随着腹水和肿瘤的出现呈现增长,顺铂+高剂量维生素 C 组的肿瘤质量及腹水容积明显小于其余三组,实验组的 CA125、HE4及 ROMA 明显低于对照组,顺铂+高剂量维生素 C 组的 CA125、HE4及 ROMA 则明显低于顺铂+低剂量维生素 C 组及顺铂组,实验组患恶性肿瘤的大鼠比例降低,而是否添加维生素 C 对数据则无明显影响。结论：注射较高浓度维生素 C 能增强顺铂杀伤卵巢癌的能力,并呈现一定的剂量依赖性。     

NF-κB抑制剂二硫代氨基甲酸吡咯烷提高卵巢癌细胞顺铂化疗的敏感性

目的:探讨核因子κB(nuclear factor kappa B, NF-κB)抑制剂二硫代氨基甲酸吡咯烷(pyrrolidine dithiocarbamate,PDTC)提高人卵巢癌SKOV-3细胞对顺铂(cisplatin)化疗敏感性的作用及其可能的机制.方法:用不同浓度PDTC联合顺铂在不同时间作用于卵巢癌SKOV-3细胞,MTT法观察药物作用对细胞生长的抑制,Western Blotting分析胞质内NF-κB 抑制蛋白α(inhibitor of NF-κB ,I-κBα)、胞核P65蛋白的表达;流式细胞术检测细胞凋亡.结果:PDTC(10～40 μmol/L)或顺铂(0.1～100 μg/ml )均明显抑制SKOV-3细胞的生长(P<0.05或P<0.01),并引起细胞的凋亡;小剂量PDTC(2.5、5 μmol/L)和顺铂(0.01 μg/ml)联合应用与单用顺铂比较,可明显增加细胞生长抑制率和细胞凋亡率(均P<0.05).单用顺铂组与对照组比较,胞质I-κBα蛋白减少而胞核P65蛋白增多,联合使用PDTC可逆转此现象.结论:小剂量PDTC可增强卵巢癌细胞对顺铂的敏感性,这一作用可能与PDTC增加I-κBα蛋白的表达而抑制P65蛋白进入核内有关.     

MiR-497 decreases cisplatin resistance in ovarian cancer cells by targeting mTOR/P70S6K1

The mechanism of cisplatin resistance in ovarian cancer is not clearly understood. In the present investigation, we found that the expression levels of miR-497 were reduced in chemotherapy-resistant ovarian cancer cells and tumor tissues due to hypermethylation of miR-497 promoter. Low miR-497 expression levels were associated with chemo-resistant phonotype of ovarian cancer. By analyzing the expression levels of miR-497, mTOR and p70S6K1 in a clinical gene-expression array dataset, we found that mTOR and p70S6K1, two proteins correlated to chemotherapy-resistance in multiple types of human cancers, were inversely correlated with miR-497 levels in ovarian cancer tissues. By using an orthotopic ovarian tumor model and a Tet-On inducible miR-497 expression system, our results demonstrated that overexpression of miR-497 sensitizes the resistant ovarian tumor to cisplatin treatment. Therefore, we suggest that miR-497 might be used as a therapeutic supplement to increase ovarian cancer treatment response to cisplatin.     

Downregulation of miR‐29 contributes to cisplatin resistance of ovarian cancer cells

Drug resistance is an obstacle to the treatment of ovarian cancer. Using a unique cell model, we have proven previously that a subpopulation of ovarian cancer cells is more resistant to cisplatin than are the original cells. MicroRNAs (miRNAs), small noncoding RNAs, are involved in many biological events in cancer cells. In our study, we explored whether miRNAs are involved in cisplatin resistance of ovarian cancer cells. Cisplatin‐resistant cells expressed a lower level of miR‐29a/b/c. Manipulation of microRNA‐29 (miR‐29) expression modulated cisplatin sensitivity of CP70, HeyC2, SKOV3 and A2780 ovarian cancer cells. Knockdown of miR‐29a/b/c increased the ability of cells to escape cisplatin‐induced cell death partly through upregulation of collagen type I alpha 1 (COL1A1) and increased the activation of extracellular signal‐regulated kinase 1/2 and inactivation of glycogen synthase kinase 3 beta. When combined with cisplatin treatment, knockdown of miR‐29 decreased the amount of the active form of caspase‐9 and caspase‐3. Ectopic expression of miR‐29 alone or in combination with cisplatin treatment efficaciously reduced the tumorigenicity of CP70 cells in vivo. Our data show that downregulation of miR‐29 increases cisplatin resistance in ovarian cancer cells. Taken together, these data suggest that overexpression of miR‐29 is a potential sensitizer to cisplatin treatment that may have therapeutic implications.