Down-regulated BARF1 expression induces EBV-positive gastric carcinoma cell apoptosis via activating caspase-dependent mitochondrial pathway

AIM: To investigate the effects of BARF1 down-regulation on EBV-positive gastric carcinoma cell apoptosis, and the molecular mechanisms by BARF1 silencing-mediated apoptosis. METHODS: After NUGC3 and SNU719 cells were transfected with NCsiRNA and siRNA, respectively, the protein levels of BARF1, Bcl-2, Bax, cytochrome C, caspase 3 and capase 9 were detected by Western blot, and the mRNA expression of BARF1, Bcl-2 and Bax was determined by RT-PCR. The cell viability was measured by the method of Trypan blue exclusion and the cell apoptosis was analyzed by flow cytometry analysis with Annexin V-FITC/PI staining. The expression of the apoptosis-related proteins in the cells transfected with siRNA and NCsiRNA was examined by human apoptosis antibody arrays. Mitochondrial membrane potential was determined by flow cytometry. The interaction between Apaf-1 and caspase 9 was confirmed by immunoprecipitation. RESULTS: Compared with untreated and NCsiRNA groups, BARF1 gene silencing significantly inhibited the cell viability, induced apoptosis, and reduced the mitochondrial membrane potential in the NUGC3 and SNU719 cells transfected with siRNA. BARF1 gene silencing up-regulated the expression of pro-apoptotic proteins and down-regulated the expression of anti-apoptotic proteins, and the Bcl-2/Bax ratio was significantly decreased. In BARF1 gene silencing cells, the caspase inhibitor z-VAD-fmk inhibited BARF1 silencing-mediated apoptosis, and significantly increased the levels of cleaved caspase 3 and caspase 9. The concentration of cytochrome C significantly increased as compared with NCsiRNA group, and Apaf-1 interacted with caspase 9 in the cytoplasm. CONCLUSION: BARF1 silencing induces apoptosis via the mitochondrial pathway through regulating the expression of Bcl-2 and Bax proteins in a caspase-dependent manner in the NUGC3 and SNU719 cells.     

Interaction of polymorphisms of ICAM-1 gene K469E and MCP-1 gene -2518A/G in invasion and metastasis of gastric carcinoma

AIM: To investigate the interaction of polymorphisms of intercellular adhesion molecule-1 (ICAM-1) gene K469E and monocyte chemoattractant protein-1 (MCP-1) gene -2518A/G in the invasion and metastasis of gastric carcinoma. METHODS: Based on TNM classification, 4 500 patients with confirmed gastric carcinoma from the First Affiliated Hospital of Xinxiang Medical University in China from December 2009 to November 2014 were divided into stageⅠ group, stage Ⅱgroup, stage Ⅲ group, stage Ⅳ group, and stage 0 group, with 900 cases in each group. No significant difference among the 5 groups in age, gender, ethnicity, birthplace and living habit was observed. The genetic polymorphisms of ICAM-1 gene K469E and MCP-1 gene -2518A/G were analyzed by the technique of polymorphism-polymerase chain reaction (PCR) in peripheral blood leukocytes of above-mentioned cases. RESULTS: Statistical tests showed signi-ficant differences in the frequencies of K469E (EE) and -2518A/G (GG) among each group (P<0.01). The risk of the invasion and metastasis of gastric carcinoma significantly increased in subjects with K469E (EE) genotype and in those with -2518A/G (GG) genotype. Combined analysis of the polymorphisms showed that distribution frequency of K469E (EE)/-2518A/G (GG) in stage Ⅰ group, stage Ⅱ group, stage Ⅲ group, stage Ⅳ group and stage 0 group was 39.22%, 53.22%, 59.22, 65.44% and 12.11%, respectively (P<0.01). The people who carried with K469E (EE)/-2518A/G (GG) had a high risk of the invasion and metastasis of gastric carcinoma, and statistical analysis suggested a positive interaction in a super-multiplicative model between K469E (EE) and -2518A/G (GG) in increasing the risk of the invasion and metastasis of gastric carcinoma. CONCLUSION: ICAM-1 gene K469E (EE) and MCP-1 gene -2518A/G (GG) are the risk factors in the invasion and metastasis of gastric carcinoma, and significant interactions between genetic polymorphisms of K469E and -2518A/G added the risk of the invasion and metastasis of gastric carcinoma.     

nm23基因的表达与皮肤鳞癌发生、发展及转移的关系

目的：观察nm23表达与皮肤鳞状细胞癌(鳞癌)发生、发展与转移的关系。方法；采用免疫组织化学及图像分析技术检测66例皮肤鳞癌、12例淋巴结转移灶、21例假上皮瘤样增生及20例正常皮肤中nm23表达情况。结果：皮肤鳞癌中nm23表达下调，但鳞癌中nm23表达与鳞癌的转移、TNM分期、病理分化程度及发病部位无关。结论：nm23基因表达下调是发生在鳞癌演进过程中的一个早期事件。nm23可能不具有抑制皮肤鳞癌转移的功能。     

乳腺癌术前灌注化疗与肿瘤供血的研究

本文对６例乳腺癌的肿瘤血供研究发现主要供血动脉是胸廓外侧动脉，而非肩胛下动脉和胸廓内动脉。提出行动脉灌注化疗时，不宜只行胸廓内动脉灌注，而应扩大范围，包括上述三支动脉。同时对６例乳腺癌术前灌注化疗的效果作了观察。     

干细胞及其在人类医学上的应用前景

干细胞是指从胚胎、胎儿或成年个体各种组织中分离出来的多能性细胞 ,具有体外保持未分化状态的无限增殖能力 ,在不同条件下可诱导分化为不同的细胞类型、组织甚至器官。胚胎癌细胞、胚胎干细胞、胚胎生殖细胞和成年组织干细胞是目前研究的几类主要干细胞 ,它们除作为发育生物学研究的细胞模型外 ,在人类医学领域也具有潜在的应用价值     

MDM2和p53在大肠癌组织中的表达及其意义

目的：探讨抑癌基因mdm2、p53在大肠癌组织中表达情况及与临床病理之间的关系。方法：采用免疫组化SABC法检测大肠癌79例,大肠腺瘤样息肉34例,正常大肠粘膜组织15例中MDM2、p53的表达。结果：MDM2在正常大肠组织、大肠腺瘤、大肠癌中表达阳性率分别为6.67%（1/15）、41.18%（14/34）、63.29%（50/79）;p53阳性率分别为0、35.29%（12/34）、67.09%（53/79）。MDM2、p53在正常组织、大肠腺瘤、大肠癌组织中表达率逐渐增加（P〈0.01）,两者与DukesC期、D期及远处转移相关,与年龄、性别及组织细胞分化程度无关。MDM2与p53表达之间呈正相关。结论：MDM2、p53高表达与大肠癌的发生、发展和预后相关。     

低分化鼻咽癌细胞系(CNE—2Z)及其21个单克隆株的癌细胞电泳分析

利用细胞电泳技术对低分化鼻咽癌细胞系(CNE-2Z)及其21个单克隆细胞株进行检测。CNE-2Z系平均细胞电泳率为1.43±0.35,21个单克隆平均细胞电泳率高低不一,从0.87±0.15到1.72±0.15,说明作为群体细胞系的CNE-2Z在细胞电泳方面具有明显异质性.同时,检测结果初步提供了21个单克隆株的纯度和转移能力的线索.     

5-Lipoxygenase expression in benign and malignant canine prostate tissues

5-Lipoxygenase (5-LO) is overexpressed in human prostate carcinomas (PCs), and its inhibition decreases proliferation and induces apoptosis in prostate cancer cell lines. We hypothesized that 5-LO would be overexpressed in canine PC compared with benign prostate tissue and may be important in the pathogenesis of the disease. Immunoblot analysis of canine PC and benign prostatic hyperplasia (BPH) tissues demonstrated 5-LO expression in both. 5-LO immunohistochemical staining was not significantly different within the stromal or epithelial components of canine primary PC, BPH or suppurative prostatitis, suggesting that differential expression of this enzyme does not occur in these conditions. The percentage of tumour cells expressing 5-LO was significantly lower in metastatic PC lesions compared with primary PC (P < 0.0001). This decreased expression may indicate down-regulation or altered expression of the enzyme with progression of canine PC to a metastatic phenotype.     

Single-agent gemcitabine chemotherapy in dogs with hepatocellular carcinomas

The goal of this study was to determine the efficacy and tolerability of gemcitabine in dogs diagnosed with hepatocellular carcinoma (HCC). Eighteen dogs were examined retrospectively (4 massive HCC, 10 nodular HCC and 4 diffuse HCC). All dogs received gemcitabine at 350-400 mg m(-2) weekly for 5 weeks. Toxicity was graded using VCOG-CTCAE guidelines and response was monitored with serial abdominal ultrasounds. Fifteen dogs completed all five cycles. Toxicity was minimal and consisted of grade I/II vomiting, anorexia and diarrhoea and two episodes of grade III neutropenia. Median survival time for all dogs was 983 days. Median progression free interval was 971 days. Based on the results of this study, surgery remains the best treatment for HCC, despite incomplete resection. There was no improvement in the survival of those diagnosed with nonresectable HCC treated with gemcitabine chemotherapy.     

Radiosensitivity and capacity for radiation-induced sublethal damage repair of canine transitional cell carcinoma (TCC) cell lines

Understanding the inherent radiosensitivity and repair capacity of canine transitional cell carcinoma (TCC) can aid in optimizing radiation protocols to treat this disease. The objective of this study was to evaluate the parameters surviving fraction at 2 Gy (SF(2) ), α/β ratio and capacity for sublethal damage repair (SLDR) in response to radiation. Dose-response and split-dose studies were performed using the clonogenic assay. The mean SF(2) for three established TCC cell lines was high at 0.61. All the three cell lines exhibited a low to moderate α/β ratio, with the mean being 3.27. Two cell lines exhibited statistically increased survival at 4 and 24 h in the dose-response assay. Overall, our results indicate that the cell lines are moderately radioresistant, have a high repair capacity and behave similarly to a late-responding normal tissue. These findings indicate that the radiation protocols utilizing higher doses with less fractionation may be more effective for treating TCC.