ObjectiveTo construct the recombinant adenovirus vector carrying antisense multidrug resistanceassociated protein (MRP) and transfect the human drugresistant hepatocellular carcinoma cell line(SMMC7721/ADM). MethodsThe fragment of MRP gene encoding 5′region was cloned reversely into the shuttle plasmid pAdTrackCMV, with the resultant plasmid and the backbone plasmid pAdEasy1,the homologous recombination took place in the bacteria and the recombinant adenoviral plasmid was generated. The adenoviruses were packaged and amplified in 293 cells. Then the cell line of SMMC7721/ADM was transfected with the resultant adenoviruses.ResultsThe recombinant adenovirus vector carrying antisense MRP was constructed successfully. The viral titer was 2.5×109 efu/ml, and more than 90% SMMC7721/ADM cells could be transfected when the multiplicity of infection（MOI） was 100. ConclusionThe recombinant adenovirus vector constructed by us could introduce the antisense MRP into the human drugresistant hepatocellular cell line effectively, which would provide experimental basis for the mechanisms and reversal methods of the multidrug resistance in human hepatocellular carcinoma.
Objective To review the application advancements of ATP-binding cassette (ABC) transporter in medical research.Methods Relevant literatures about the applications of ABC families in medical research were reviewed. Results ABC families mainly took roles in transporting substances across cell membrane. Some of them were useful for the prediction of drug resistance and the prognosis of malignant tumors. Others were target s for molecular researches. Their expressions or mutations might be related with the occurrence of diseases. Conclusion ABC families are very important in the diagnosis and therapy for diseases. Thus they are very promising tools for future medical research.
Objective To predict clinical chemotherapy sensitivity of primary non-small cell lung cancer（NSCLC） by methylthiazal （MTT） tumor chemosensitivity assay method in vitro and detection of multidrug resistance gene1 （MDR1）, and provide reference for clinical individualized treatment. Methods We selected 80 fresh primary NSCLC samples from NSCLC patients who underwent surgical resection in Zibo Central Hospital Affiliated to Binzhou Medical College between January 2009 and December 2011. There were 46 male patients and 34 female patients with their median age of 54 （29 to 81）years. Viable NSCLC cells obtained from malignant tissue were tested for their sensitivity to cisplatin （DDP）, gemcitabine （GEM）, docetaxe （DOC）, etoposide （VP-16） ,and vinorelbine （NVB） using MTT assay in vitro. Fluorescent quantitative reverse transcriptase-polymerase chain reaction （RT-PCR） was used to analysis the expression level of multidrug resistance gene1 （MDR1）. Results After exposure to antitumor drugs, morphologic changes, decrease of metabolic activity, and apoptosis were detected in NSCLC cells. MTT results showed that different individual cancer cells had different chemosensitivity to antitumor drugs, and cancer cells also had different chemosensitivity to different antitumor drugs. Inhibitory rates of cancer cells exposed to DOC, GEM, and VP-16 were significantly higher than those of cancer cells exposed to DDP and NVB （42.5%±9.5%, 40.5%±6.5%, 38.4%±7.6% versus 31.5%±8.5%，32.5%±7.8%, P＜0.05）.The positive rate of MDR1 in tumor tissues was 40.0% （32/80）. The expression of MDR1 was not associated with tumor histological type, degree of differentiation, lymph node metastasis and TNM stage. The expression of MDR1 was associated with resistance to NVB （χ2=5.209，P=0.022），GEM （χ2=4.769，P=0.029），VP-16 （χ2=4.596，P=0.032），and DDP（χ2=6.086，P=0.014）, but not associated with resistance to DOC（χ2=0.430，P=0.512）. Conclusion MTT chemosensitivity assay can effectively predict clinical chemotherapy sensitivity. Detection of MDR1, together with MTT chemosensitivity assay, can more accurately predict NSCLC chemosensitivity and be a guide for individualized chemotherapy of NSCLC.
【Abstract】 Objective To detect the expression of lung resistance protein (LRP) and investigate its significance in pancreatic carcinoma cell lines (SW1990, PCT-2, PCT-3, PCT-4, Aspc-1, Capan-1, Mia-PaCa-2 and Panc-1). Methods Reverse transcription PCR (RT-PCR) and immunocytochemistry (ICC) were carried out to investigate the expression of LRP. Results LRP mRNA was absent in PCT-2 cell line by RT-PCR. Mild to moderate expression level was found in other pancreatic carcinoma cell lines. PCT-4, Aspc-1 and Panc-1 presented the highest LRP mRNA expression level, in contrast, SW1990, PCT-3, Capan-1 and Mia-PaCa-2 showed moderate LRP mRNA expression. The median value was 0.56±0.33. LRP was further validated by ICC. Absent to weak protein expression of LRP was found in PCT-2 and PCT-3. Overexpressed LRP was present in SW1990, Capan-1 and Aspc-1, furthermore, the highest expression of LRP was found in Panc-1, Mia-PaCa-2 and PCT-4 cell lines. Conclusion All these data showed that LRP might play an important role in multidrug resistance of pancreatic carcinoma.
【摘要】 目的 剪切修复偶联因子1（ERCC1）是核苷酸外切修复家族中的重要成员，它在核酸损伤修复过程和凋亡过程中起着重要作用；存活蛋白（Survivin）属凋亡抑制蛋白家族，是迄今发现的最强的凋亡抑制因子之一。研究中初步探索晚期非小细胞肺癌（non-small-cell lung cancer，NSCLC）中ERCC1和Survivin与铂类化学疗法敏感性的关系及其相关性。 方法 2001年1月－2002年6月对51例晚期NSCLC（ⅢB或Ⅳ期）标本经免疫组织化学检测ERCC1和Survivin的表达，患者行至少2周期含铂方案化学疗法，2周期化学疗法后评价疗效，采用SPSS 13.0软件就检测指标和化学疗法疗效评价进行相关统计分析。 结果 ERCC1和Survivin在肿瘤组织中阳性表达率分别为58.8 %（30/51）和76.5 %（39/51）。ERCC1阴性组化学疗法有效率高于阳性组（Plt;0.05），5年生存时间高于阳性组（Plt;0.05）；Survivin阴性组化学疗法有效率虽高于阳性组，但无统计学意义（Pgt;0.05），其5年生存时间与阴性组比较无差别（Pgt;0.05）。Spearman相关分析提示ERCC1与Survivin之间无相关性（rs=-0.088，P=0.537）。 结论 ERCC1和Survivin可能与NSCLC的发生相关，ERCC1可能与肿瘤的预后相关，并对化学疗法疗效具有一定预测价值。ERCC1和Survivin之间耐药机制可能各不相同。【Abstract】 Objective Excision repair cross-complementing 1 (ERCC1), an important member of the DNA repair gene family, plays a key role in nucleotide excision repair and apoptosis of tumor cells. Survivin, a member of inhibitor of apoptosis protein (IAP) family, is one of the most powerful factors in inhibiting apoptosis up to now. This study is to explore the value of ERCC1 and Survivin in predicting the sensitivity of non-small cell lung cancer (NSCLC) to platinum-based chemotherapy and the interrelationship between the two markers. Methods From January 2001 to June 2002, expressions of ERCC1 and Survivin of 51 advanced NSCLC patients (Ⅲ B or IV) were tested through immunohistochemistry. The patients were treated with at least 2 cycles of platinum-based chemotherapy. The curative effect was evaluated later, and the relationship among detected data, curative effect of chemotherapy and patients′ clinical parameters were analyzed with SPSS 13.0 software. Results The positive expression rates of ERCC1 and Survivin in NSCLC tissues were 58.8 % (30/51) and 76.5 % (39/51), respectively. The effective rate of chemotherapy and 5-year survival rate for the negative group of ERCC1 were significantly higher than those for the positive group (Plt;0.05). The results for Survivin were similar to those for ERCC1, but there was no statistical significance (Pgt;0.05). We also found there was no relationship between ERCC1 and Survivin by Spearman′s correlation analysis (rs=-0.088, P=0.537). Conclusion ERCC1 and Survivin may be correlated with the development of NSCLC, and ERCC1 may be related to curative effect and prognosis of NSCLC. There was probably no mechanism of coordination or regulation in multi-drug resistance between ERCC1 and Survivin.
【Abstract】Objective To review the advances in overcoming multidrug resistance of tumors caused by mdr1 gene.Methods Different ways of overcoming multidrug resistance of tumors caused by mdr1 gene in the literatures were reviewed. Results One of the important reasons causing multidrug resistance was due to the overexpression of mdr1 gene and its product Pglycoprotein. There were two ways to overcome multidrug resistance of tumors through mdr1 genes mRNA and its product Pglycoprotein effectively.Conclusion The clinical test of the unitary way to overcome multidrug resistance of tumors is unsatisfactory, combining different ways to overcome multidrug resistance of tumors will be the hot spot of tumors research in the future.
Objective To investigate the reversal of the multidrug resistant gene mdr1 in vivo by antisense oligodeoxynucleotide （ASODN） on the basis of study in vitro. Methods The cultured drug-resistant human hepatocellular carcinoma cells were injected under the skin of axilla to establish the tumor model of nude mice. mdr1 ASODN accompanied by Lipofectamine were injected locally and ADM was injected intraperitoneally. Control 1 and control 2 were locally injected by Lipofectamine and normal saline separately, and ADM was also injected intraperitoneally. Results As time went on the tumor size increased and from the 5th day on alterations were marked, tumor size in different time phase showed marked difference to the prior time phase with significant difference (P＜0.05）. Tumor size in group ASODN was marked smaller than that of other 3 groups after the 5th day (P＜0.05)，while tumor size of group control 1,2 and group SODN in different phase showed no significant difference (Pgt;0.05). The results suggested that SODN and Lipofectamine showed no marked effect on tumor growth of nude mice and ASODN had marked inhibition effect on tumor growth. Conclusion mdr1 ASODN can also reverse multidrug resistance of drug-resistant human hepatocellular carcinoma cells in vivo. After the treatment the tumor’s growth in nude mice will slow down in a range of time.
Objective To detect the characteristic of multidrug resistance gene products expressions in gastric cancer tissues, including glutathione-s-transferase π (GST-π), P-glycoprotein (P-gp), topoisomerase Ⅱ (Topo-Ⅱ), thymidylate synthase (TS), and multidrug resistance related protein (MRP), and analyze their clinical significance for the therapy of gastric cancer. Methods SP immunohistochemical stain was used to detect GST-π, P-gp, Topo-Ⅱ, TS and MRP expressions in sample of 48 gastric cancer tissues and 10 normal gastric mucosa. And their corresponding clinical data were comprehensive analyzed. Results The expressions of GST-π, P-gp, Topo-Ⅱ, TS and MRP had notable differences between the gastric cancer tissues and normal gastric mucosa (GST-π： P＜0.01； P-gp： P＜0.01； Topo-Ⅱ： P＜0.01； TS： P＜0.05； MRP： P＜0.05). Positive expression rates of GST-π, P-gp, Topo-Ⅱ, TS and MRP in gastric cancer tissues were 72.9% (35/48), 56.3% (27/48), 83.3% (40/48), 41.7% (20/48) and 39.6% (19/48), and positive expression rates of them in normal gastric mucosa were 10.0% (1/10), 0 (0/10), 0 (0/10), 0 (0/10) and 0 (0/10) corresponding. Their positive expression rates were closely relevant to the degree of differentiation (P＜0.01), but not to the patients’ sex, age, tumour site, size of tumour, invasive depth and lymph node metastasis (Pgt;0.05). Conclusions The expressions of GST-π, P-gp, Topo-Ⅱ, TS and MRP in gastric cancer tissues exist obvious heterogeneity. Their overexpression underlie the multidrug resistance of gastric cancer. The joint detection of GST-π, P-gp, Topo-Ⅱ, TS and MRP can be looked as an important symbol for guiding its chemotherapy.