黄芪多糖降低A549/DDP肺腺癌细胞顺铂耐药机制研究

目的:研究黄芪多糖对A549/DDP肺腺癌细胞顺铂耐药的影响及可能机制。方法:将A549/DDP顺铂耐药肺腺癌细胞分为CON组（未行黄芪多糖及顺铂处理）、APS组（仅用黄芪多糖处理）、DDP组（仅用顺铂处理）及A+D组（黄芪多糖联合顺铂处理），比较四组细胞增殖、细胞周期及凋亡率和耐药基因表达的差异。结果:A+D组细胞d1-d7吸光度、S期、G2/M期和PI均显著低于CON组、APS组和DDP组细胞（均P<0.05），G0/G1期和凋亡率均显著高于CON组、APS组和DDP组细胞（均P<0.05）；APS组和A+D组细胞MDR1和MRP基因mRNA表达无明显差异（均P>0.05），且均显著低于CON组和DDP组（均P<0.05）。结论:黄芪多糖可显著改善A549/DDP肺腺癌细胞对顺铂耐药性，可能与黄芪多糖显著降低MDR1和MRP有关。     

黄芪多糖通过调控miR-20a/TGFBR2 分子轴降低结直肠癌HT-29/DDP细胞的顺铂耐药性

[摘要] 目的：探讨黄芪多糖（APS）通过调控miR-20a/TGFBR2 分子轴对结直肠癌（CRC）顺铂耐药细胞HT-29/DDP增殖、侵袭、凋亡和耐药性的影响及其机制。方法：以人CRC HT-29 细胞、HT-29/DDP细胞为亲本和耐药细胞模型,将HT-29/DDP细胞随机分为4 组：对照组、APS 处理组、过表达miR-20a + APS 组、沉默TGFBR2 + APS 组。用不同质量浓度的APS（0、0.5、1.0、1.5 和2.0 mg/ml）处理HT-29/DDP细胞后,以qPCR和Wb实验检测细胞中miR-20a 和TGFBR2 的表达水平;用CCK-8、Transwell 和Annexin V-FITC/PI 染色流式细胞术检测对HT-29/DDP细胞增殖、侵袭和凋亡的影响;用双荧光素酶报告基因验证miR-20a 与TGFBR2的靶向作用关系。构建裸鼠皮下CRC HT-29/DDP细胞移植瘤模型,观察APS对移植瘤生长的影响及其机制。结果：APS显著抑制HT-29/DDP 细胞的增殖（P<0.01）,且呈剂量依赖性。miR-20a 在经APS 处理后的HT-29/DDP 细胞中低表达（P<0.01）、TGFBR2 的表达水平显著上调（P<0.01）。双荧光素酶报告基因证实miR-20a 靶向作用TGFBR2 并下调其表达水平。体内外实验证实APS通过靶向下调miR-20a 对TGFBR2 的抑制作用,提高HT-29/DDP细胞的药物敏感性,进而抑制该细胞增殖、侵袭和促进凋亡（均P<0.01);同时发现,该作用与抑制PCNA、Bcl-2 蛋白而促进Bax、Caspase-3 蛋白表达有关联。结论：APS通过下调miR-20a对TGFBR2 表达的抑制作用,从而逆转HT-29/DDP细胞对顺铂的耐药性。     

柚皮苷逆转人卵巢癌耐药SKOV3／DDP细胞耐药性及逆转机制的研究

目的 研究柚皮苷对卵巢癌顺铂（DDP）耐药细胞SKOV3／DDP体外增殖的影响及耐药逆转作用,并初步探讨相关耐药机制。方法采用MTT法测定DDP对SKOV3和SKOV3／DDP细胞的半数抑制浓度（IC₅₀）,柚皮苷对SKOV3／DDP细胞的增殖抑制作用及柚皮苷联合DDP对SKOV3／DDP细胞的增殖抑制作用。筛选出非细胞毒性的柚皮苷浓度,将实验细胞分为空白对照组、2.5 μg／ml DDP组、10 μmol/L柚皮苷组、10 μmol/L柚皮苷联合2.5 μg／ml DDP组,分别采用RT-PCR和Western blotting测定各组作用48 h后耐药基因MDR1 mRNA及MRP2 mRNA的表达及其相应的表达产物P-gp、MRP2蛋白的表达水平。结果1～32 μg／ml DDP处理SKOV3及SKOV3／DDP细胞48 h后,SKOV3细胞的IC₅₀为5.48 μg／ml,SKOV3／DDP细胞为14.93 μg／ml,耐药指数为2.72。柚皮苷对SKOV3／DDP细胞有明显的增殖抑制作用,且呈剂量和时间依赖性。选取10 μmol／L柚皮苷作为逆转耐药实验浓度,10 μmol／L柚皮苷联合DDP作用48 h后,SKOV3／DDP细胞对DDP的耐药指数为1.62,逆转倍数为1.68。RT-PCR及Western blotting检测显示,柚皮苷联合DDP组与DDP单药组比较,MDR1 mRNA、MRP2 mRNA表达及P-gp、MRP2蛋白表达均明显下降,差异有统计学意义（P＜0.05）。结论柚皮苷对卵巢癌SKOV3／DDP细胞的体外增殖具有明显抑制作用,并能逆转SKOV3／DDP细胞的耐药性,其逆转耐药的机制可能与下调耐药基因MDR1 mRNA及MRP2 mRNA及相应的P-pg、MRP2蛋白的表达有关。     

姜黄素逆转卵巢癌耐药细胞株COC1/DDP耐药性及机制的研究

目的：探讨姜黄素对耐药卵巢癌细胞增殖、凋亡及对顺铂敏感性的影响并探讨其机制。方法：采用MTT法检测顺铂、姜黄素、顺铂与姜黄素合用对COC1/DDP细胞的生长抑制作用;用流式细胞仪检测2.5μg/ml顺铂、20μmol/L姜黄素、2.5μg/ml顺铂与20μmol/L姜黄素合用作用于COC1/DDP细胞48h后的细胞凋亡率;RT-PCR法检测上述各组细胞凋亡相关基因Bcl-2、Caspase-3、Survivin的表达。结果：姜黄素浓度在（15-35）μmol/L以内时对COC1/DDP有明显的增殖抑制作用,且呈一定的剂量-效应关系。顺铂的浓度在（1.25-5）μg/ml时加入姜黄素20μmol/L后耐药细胞生存率下降明显（P〈0.05）,尤以顺铂2.5μg/ml和姜黄素20μmol/L联合作用时,耐药细胞生存率下降最明显;COC1/DDP中顺铂与姜黄素联合用药与单独用顺铂相比,凋亡率明显增加（P〈0.05）;顺铂与姜黄素联合用药与单独用顺铂相比Bcl-2、Sur-vivin mRNA的表达明显降低（P〈0.05）,Caspase-3 mRNA的表达明显增高（P〈0.05）。结论：姜黄素能够显著抑制COC1/DDP增殖,并能增强该细胞系对顺铂的敏感性,其机制可能与降低Bcl-2、Survivin基因的表达,增加Caspase-3基因的表达有关。     

上调miRNA-506对肺癌耐药细胞株A549/DDP耐药性的逆转及其机制

目的:探讨微小核糖核酸（miRNA）-506对人非小细胞肺癌顺铂耐药株A549/DDP细胞耐药性的逆转及其可能机制。方法:构建miRNA-506 模拟物,应用脂质体法转染A549/DDP细胞。应用实时逆转录酶链聚合反应（qRT-PCR）法验证各组细胞中miRNA-506的表达情况,CCK8法检测顺铂对细胞的抑制作用。流式细胞术Annexin V／PI双染检测各组细胞的凋亡。Western blot检测MDR1、MRP1、Bcl-2、Bax的蛋白表达。结果:qRT-PCR结果显示,miRNA-506转染组miRNA-506的表达量明显高于对照组（P<0.05）。CCK8结果显示,上调miRNA-506 增强A549/DDP细胞对顺铂的敏感性。流式细胞术结果显示上调miRNA-506 促进顺铂诱导的A549/DDP细胞凋亡。上调miRNA-506可以使A549/DDP细胞MDR1、MRP1和Bcl-2蛋白的表达下降,使Bax蛋白的表达升高。结论:上调miRNA-506能逆转A549/DDP细胞对顺铂的耐药,这一过程可能通过miRNA-506调控多药耐药蛋白和凋亡相关蛋白实现。     

下调Beclin1 抑制卵巢癌A2780/DDP细胞对顺铂的耐药性

目的：探究敲减Beclin1 表达对卵巢癌细胞A2780 对顺铂耐药的影响及其相关机制。方法：以Western blotting 及qPCR 检测卵巢癌细胞株A2780 及耐药细胞株A2780/DDP 中Beclin1 的表达情况；A2780/DDP 细胞转染Beclin1 siRNA 后，用MTT法检测细胞对顺铂敏感性的变化，克隆形成实验检测各组细胞的克隆形成情况，流式细胞术检测各组细胞的凋亡，MDC荧光染色检测细胞的自噬情况，Western blotting 检测自噬相关蛋白、溶酶体相关膜蛋白Lamp-2 以及组织蛋白酶Cathepsin B的表达情况。结果：顺铂耐药细胞株A2780/DDP 中Beclin1 mRNA及蛋白的表达水平均明显高于A2780 细胞株（均P<0.05），在A2780细胞中加入顺铂刺激后Beclin1 蛋白的表达水平显著升高（P<0.05）。敲减Beclin1 表达可促进顺铂诱导的A2780/DDP 细胞的凋亡（P<0.05）、抑制细胞自噬的发生（P<0.05）、减少细胞克隆形成（P<0.05）和增加细胞对顺铂的敏感性（P<0.05）；Western blotting结果显示，敲减Beclin1 可上调A2780/DDP 细胞中cleaved-caspase 3 和Cathepsin B的蛋白水平，下调Atg3、Atg7、LC3Ⅱ/Ⅰ、Lamp-2的表达水平（均P<0.05）。结论：敲减Beclin1 表达可提高A2780/DDP细胞对顺铂的敏感性，其机制可能与调节自噬相关蛋白表达抑制细胞保护性自噬和影响溶酶体功能，从而促进顺铂诱导耐药细胞凋亡有关。     

转录因子SP1 通过调控ABCC1 影响小细胞肺癌H446/DDP 细胞耐药的 机制

目的：探讨敲减转录因子特异蛋白1（SP1）对小细胞肺癌（SCLC）H466/DDP 细胞顺铂（DDP）耐药的影响及其分子机 制。方法：构建敲减SP1同时过表达ATP 结合盒亚家族C 成员1（ABCC1）的SCLC H466/DDP 细胞,采用IHC 法检测SP1、 ABCC1 在非耐药和耐药SCLC 组织中的表达,用Spearman r 法分析SP1 与ABCC1 在SCLC 组织中表达的相关性;WB 法检测 SP1、ABCC1、CD44 在转染后H446/DDP 细胞中的表达;CCK-8 法、FCM 术、微球实验检测转染后H446/DDP 细胞的增殖、凋亡及 自我复制能力的变化;染色质免疫共沉淀（CHIP）实验检测SP1 是否是ABCC1 的转录因子。结果：耐药细胞H446/DDP 和耐药 SCLC 组织中的SP1、ABCC1 蛋白水平均高于H446 细胞和非耐药SCLC 组织（均P<0.05）,SCLC 组织中的SP1、ABCC1 蛋白表达 呈正相关;敲减SP1 抑制H446/DDP 细胞的增殖活力,降低CD44、ABCC1 蛋白表达水平、减少细胞微球形成数（均P<0.05）,促进 细胞凋亡（P<0.05）;SP1 是ABCC1 的转录因子。结论：转录因子SP1 通过调控ABBC1 的表达影响SCLC H446/DDP 细胞的耐 药,SP1 是SCLC 对DDP 耐药的潜在治疗靶点。     

顺铂耐药乳腺癌细胞株的建立及FANCF 基因在耐药中的作用

[摘要] 目的：探讨三阴性乳腺癌顺铂（cisplatin, DDP)耐药细胞和敏感细胞中FA/BRCA通路关键基因FANCF的表达和功能,以及与DDP耐药的相关性。方法：DDP浓度递增法诱导建立乳腺癌细胞MDA-MB-231的DDP耐药细胞株MDA-MB-231/DDP;通过RNAi技术敲减MDA-MB-231 敏感细胞和DDP耐药细胞中FANCF,并在mRNA和蛋白水平进行敲减效果验证。CCK-8 法检测DDP耐药细胞株增殖活性,Western blotting 法检测该细胞中FANCF蛋白表达,流式细胞仪检测MDA-MB-231细胞周期和凋亡情况,实时定量PCR（RT-qPCR）法检测FANCF mRNA的表达。结果：MDA-MB-231细胞DDP诱导3个月建立的MDA-MB-231/DDP细胞株耐药指数为13.5,其G0/G1 期细胞增多、S期和G2/M期细胞减少。MDA-MB-231/DDP细胞中FANCF mRNA和蛋白表达水平显著升高（均P<0.01）。FANCF敲低后MDA-MB-231/DDP细胞凋亡增加,细胞对DDP的药物敏感性显著升高（均P<0.01）。结论：FANCF基因通过抗凋亡作用导致MDA-MB-231细胞对DDP的耐药性,FANCF是乳腺癌治疗的一个潜在靶点。     

黄芪多糖逆转EC109/DDP食管癌细胞顺铂耐药的可能机制

目的 研究黄芪多糖逆转EC109/DDP食管癌细胞顺铂耐药的可能机制.方法 将EC109/DDP顺铂耐药食管癌细胞分为CON组(未行任何药物干预)、APS组(仅黄芪多糖干预)、DDP组(仅顺铂干预)及APD组(黄芪多糖及顺铂干预),比较4组细胞吸光度、细胞周期、凋亡率及MRP和GST-π基因表达的差异.结果 APD组EC109/DDP顺铂耐药食管癌细胞的D1~D6吸光度、S期、G2/M期和增殖指数均低于CON组、APS组和DDP组(P<0.05),G0/G1期和凋亡率均高于CON组、APS组和DDP组(P<0.05).CON组和DDP组间、APS组和APD组间EC109/DDP顺铂耐药食管癌细胞MRP和GST-π基因mRNA表达差异均无统计学意义(P>0.05);APS组和APD组细胞MRP和GST-π基因mRNA表达均低于CON组和DDP组(P<0.05).结论 黄芪多糖可逆转EC109/DDP顺铂耐药食管癌细胞对顺铂的耐药性,其可能机制与黄芪多糖显著降低MRP和GST-π基因表达有关.     

lncRNA FAL1通过调控MAPK通路对卵巢癌细胞化疗耐药性的影响及其机制

目的观察lncRNA FAL1在卵巢癌细胞及其耐药细胞株中的表达差异,探索下调lncRNA FAL1对细胞化疗耐药性的影响及机制。方法qRT-PCR法检测SKOV3和COC1细胞及其耐药细胞株FAL1基因表达水平,转染FAL1-siRNA下调FAL1基因,MTT检测细胞增殖能力,Transwell法检测细胞侵袭能力,平板克隆形成实验检测细胞克隆能力,Western blot法检测细胞耐药相关蛋白MDR-1、MPR-1、ABCG2和MAPK通路相关蛋白p38 MAPK、ERK1/2、JNK磷酸化水平。将已转染FAL1-siRNA的SKOV3/DDP和COC1/DDP细胞注射到BALB/c裸鼠皮下,定期测量瘤体积并称重。结果与SKOV3和COC1细胞比较,SKOV3/DDP和COC1/DDP细胞对DDP的敏感度降低,FAL1基因的表达水平升高(P<0.01)。转染FAL1-siRNA后,SKOV3/DDP和COC1/DDP细胞对DDP的敏感度增加(P<0.01),侵袭能力(P<0.05)和克隆能力降低(P<0.01),细胞中MDR-1、MPR-1、ABCG2表达水平(P<0.01)和p38 MAPK、ERK1/2、JNK磷酸化水平降低(P<0.05),皮下移植瘤的体积和瘤质量显著降低(P<0.01)。结论下调lncRNA FAL1可显著降低卵巢癌耐顺铂细胞株的化疗耐药性,抑制耐药细胞在体内的增殖能力,其作用机制与抑制MAPK信号通路的活化有关。     

Bacteria and cancer--antagonisms and benefits

There is considerable historical and recent evidence concerning the antagonisms between acute bacterial infections or their toxins and cancer and allied diseases. These data provide renewed incentives to undertake clinical programmes with mixed bacterial vaccines in many countries at the present time.     

VEGF及KDR在大肠腺瘤和腺癌中的表达及意义

目的：探讨VEGF和KDR在大肠腺瘤和大肠腺癌中的表达及临床病理特征的关系。方法：大肠腺瘤和大肠腺癌组织标本各100例,采用免疫组织化学染色法检测VEGF和KDR在标本中的表达情况。结果：VEGF和KDR在大肠腺癌组中的阳性表达明显高于大肠腺瘤组（P〈0.05）;在正常大肠黏膜均未见VEGF和KDR表达的阳性染色;VEGF阳性表达组中KDR的阳性表达率为70%,显著高于VEGF阴性表达组中KDR的阳性表达率16%,两组比较有统计学意义（P〈0.01）。结论：大肠腺癌组织中KDR的表达与肿瘤大小、转移情况、浸润深度密切相关;VEGF和KDR在大肠腺瘤中的表达与患者的年龄、性别及分型均无相关性,而与增生程度相关（P〈0.05）。在大肠腺癌患者中VEGF及KDR表达更高,二者具有协同效应。     

Religiosity and physical and emotional functioning among African American and White colorectal and lung cancer patients

The literature suggests that religiosity helps cope with illness. The present study examined the role of religiosity in functioning among African Americans and Whites with a cancer diagnosis. Patients were recruited from an existing study and mailed a religiosity survey. Participants (N = 269; 36% African American, 56% women) completed the mail survey, and interview data from the larger cohort was utilized in the analysis. Multivariate analyses indicated that in the overall sample religious behaviors were marginally and positively associated with mental health and negatively with depressive symptoms. Among women, religious behaviors were positively associated with mental health and negatively with depressive symptoms. Religiosity was not a predictor of study outcomes for men. Among African Americans, religious behaviors were positively associated with mental health and vitality. Among Whites, religious behaviors were negatively associated with depressive symptoms. These findings suggest a mixed role of religious involvement in cancer outcomes. The current findings may have applied potential in the areas of emotional functioning and depression.     

Genetic polymorphisms of alcohol and aldehyde dehydrogenases and risk for esophageal and head and neck cancers

Alcoholic beverages are causally related to cancer of the oral cavity, pharynx, larynx and esophagus. Ethanol is oxidized to acetaldehyde and then to acetate by alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), both of which have genetic polymorphisms. A review of case-control studies of the effects of ALDH2, ADH2 and ADH3 genotypes shows consistently positive associations between inactive heterozygous ALDH2 and the less-active ADH2 genotypes and the risk for esophageal cancer in East Asian heavy drinkers and this enzyme-related vulnerability may extend to light-to-moderate drinkers. Some studies suggest similar associations with the risk for head and neck cancer in moderate-to-heavy-drinking Japanese. An established carcinogen in experimental animals, acetaldehyde can interact with human DNA. ALDH2-associated cancer susceptibility fits into a scenario in which acetaldehyde plays a critical role in the development of human cancer. Alcohol flushing and drinking behavior may partly explain this carcinogenic effect in carriers of less-active ADH2 genotypes. Whether the ADH3 genotype influences head and neck cancer risk in Western nations is controversial. Professional and public education about risky conditions connected to the ALDH2 and ADH2 genotypes and environmental factors is important in a new strategic approach to the prevention of alcohol-related cancers in East Asians. The use of simple tests to identify inactive ALDH2 on the basis of alcohol flushing responses could benefit many people, by helping them to identify their own cancer risks. Such testing could also help clinicians diagnose esophageal cancer earlier, through the use of endoscopic screening in the high-risk population.     

Religiosity and Physical and Emotional Functioning Among African American and White Colorectal and Lung Cancer Patients

The literature suggests that religiosity helps cope with illness. The present study examined the role of religiosity in functioning among African Americans and Whites with a cancer diagnosis. Patients were recruited from an existing study and mailed a religiosity survey. Participants (N = 269; 36% African American, 56% women) completed the mail survey, and interview data from the larger cohort was utilized in the analysis. Multivariate analyses indicated that in the overall sample religious behaviors were marginally and positively associated with mental health and negatively with depressive symptoms. Among women, religious behaviors were positively associated with mental health and negatively with depressive symptoms. Religiosity was not a predictor of study outcomes for men. Among African Americans, religious behaviors were positively associated with mental health and vitality. Among Whites, religious behaviors were negatively associated with depressive symptoms. These findings suggest a mixed role of religious involvement in cancer outcomes. The current findings may have applied potential in the areas of emotional functioning and depression.     

New and emerging radiosensitizers and radioprotectors

The combination of chemotherapy and radiation has led to clinical breakthroughs in several disease sites, and current work continues to define optimum combinations of proven chemotherapy as well as more recently available, noncytotoxic agents. Administration of systemic therapies allows modulation of radiation response to improve tumor control (radiosensitization) or to prevent normal tissue toxicity (radioprotection). Substantial progress has been made in identifying the targets of standard chemotherapeutic radiation sensitizers and protectors as well as in the introduction of a new generation of molecularly targeted therapies in combination with radiation. We have reviewed the most recent, predominantly early phase clinical trials combining systemic agents with radiation. Although the proof of an improved schedule ultimately needs to come from well-run Phase III trials, the search among schedules could be shortened by the use of surrogate endpoints such as presence of active drug metabolites in the tumor. This has been accomplished only in a few cases and needs to become a more standard part of radiation sensitizer and protector trials.