潜伏表达癌调蛋白的HSV-1减毒载体能有效治疗大鼠机械性视神经损伤

目的评价潜伏表达癌调蛋白OCM的HSV-1减毒型载体(1716-OCM)在大鼠机械性视神经损伤中的治疗作用及安全性。方法体外细胞感染模型中检测重组病毒增殖特性及OCM表达。大鼠按随机数字表法分为3组(对照组、1716-OCM注射组和野生型病毒角膜感染组),每时间点3只/组,于感染后7、14、30、60 d免疫荧光法检测OCM基因及病毒蛋白gB在大鼠视网膜和下丘脑中的表达。大鼠视神经损伤模型中,大鼠按随机数表法分为4组(假手术组,PBS治疗对照组,1716-OCM感染组及1716-OCM感染加cAMP增敏组),5只/组。治疗45 d后,视觉诱发电位(FVEP)检测视觉电生理功能。免疫荧光法检测视网膜RGCs数量及神经髓鞘蛋白表达。结果重组减毒型1716-OCM在体外细胞感染中病毒增殖远低于野生型病毒,其能够介导OCM有效表达。重组病毒能够介导OCM在大鼠眼部RGC层及脉络膜层表达。相比于野生型病毒,1716-OCM未引发显著的眼部组织结构破坏。在视神经损伤模型中,相比于未治疗组,1716-OCM联合cAMP治疗能够显著促进视网膜RGC存活(P=0.007)并抑制视神经脱髓鞘(P=0.03)。FVEP分析显示1716-OCM联合cAMP显著促进大鼠ΔN1-P1峰振幅恢复(P<0.001)。结论减毒型重组1716-OCM能够介导OCM在大鼠视网膜表达,玻璃体腔注射1716-OCM重组病毒和cAMP能够有效治疗大鼠机械性视神经损伤。

Bystin-like protein is upregulated in hepatocellular carcinoma and required for nucleologenesis in cancer cell proliferation

The bystin-like （BYSL） gene was previously characterized to encode an accessory protein for cell adhesion that participates in early embryo implantation. It is also involved in 40S ribosomal subunit biogenesis and is found to be expressed in rapidly growing embryo and cancer cell lines. In order to explore the role of BYSL in cancer cell proliferation and growth, we used hepatocellular carcinoma （HCC） as a model. Here, we report that BYSL is crucial for HCC cell growth both in vitro and in vivo. Expression levels of BYSL mRNA and protein in human HCC specimens were markedly increased compared with those seen in adjacent non-cancerous tissue. In vitro, inhibition of BYSL by short hairpin RNA decreased HCC cell proliferation, induced apoptosis and partially arrested the cell cycle in the G2/M phase. In vivo, HCC cells treated with BYSL siRNA failed to form tumors in nude mice after subcutaneous implantation. To determine the cellular basis for BYSL RNAi-induced cell growth arrest, BYSL subcellular localization in mitotic and interphase HepG2 cells was examined. BYSL was present at multiple stages during nucleologenesis, including in nucleolus-derived foci （NDF）, perichromosomal regions and the prenucleolar body （PNB） during mitosis. BYSL depletion remarkably suppressed NDF and PNB formation, and disrupted nucleoli assembly after mitosis, resulting in increased apoptosis and reduced tolerance of HCC cells to serum starvation. Taken together, our studies indicate that upregulated BYSL expression plays a role in hepatocarcinogenesis.

Co-expression of heat shock protein 70 and glucose-regulated protein 94 in human gastric carcinoma cell line BGC-823

AIM:To investigate the co-expression and significance of heat shock protein 70 (HSP70) and glucose-regulated protein 94 (grp94) in human gastric carcinoma cell line BGC-823. METHODS: The expression and localization of HSP70 and grp94 in human gastric carcinoma cell line BGC-823 were determined by immunocytochemistry and indirect immunofluorescence cytochemical staining. Flow cytometry was used to analyze the correlation between expression of HSP70, grp94 and cell cycle in BGC-823 cell line. RESULTS: Gastric cancer cell line BGC-823 expressed high level of HSP70 and grp94. The positive rate of HSP70 and grp94 was 84.9±4.94% and 79.6±5.16%, respectively. Both of them were stained in cell plasma. There was a significant difference compared with control group (1.9±0.94%, P<0.01). During the cell cycle, HSP70 and grp94 were continuously expressed in BGC-823. CONCLUSION: HSP70 and grp94 are highly expressed in human gastric carcinoma BGC-823 cells through the whole cell cycle. There is no relationship between expression of HSP70, grp94 and cell cycle.

Expression and significance of heat shock protein 70 and glucose-regulated protein 94 in human esophageal carcinoma

AIM: To investigate the expression and significance of heat shock protein 70 (HSP70) and glucose-regulated protein 94 (grp94) in human esophageai carcinoma and adjacent normal tissues. METHODS: The expression of HSP70 and grp94 in 78 human esophageai cancer and adjacent normal tissues was studied by immunohistochemistry and pathology photograph analysis. RESULTS: Both esophageai cancer and adjacent normal tissues could express HSP70 and grp94. Of the 78 cases of esophageai carcinoma, 95.0%(72/78) showed positive HSP70, mainly stained in nuclei, while grp94 was mainly stained in cell plasma, and the positive rate was 71.8% (56/78).There was a significant difference in the expression of HSP70 and grp94 between esophageai cancer and adjacent normal tissues (P<0.01). Compared with adjacent normal tissues, there was a significant difference between differential types and HSP70 expression (P<0.01). CONCLUSION: HSP70 and grp94 express differently in cell plasma and nuclei. The expression intensity of HSP70 is related to the differentiation of esophageai carcinoma.

DELETIONS AND POINT MUTATIONS OF p16,p15 GENE IN PRIMARY TUMORS AND TUMOR CELL LINES

Aberrations of chromosome 9 p21 22 are involved in the genesis of many forms of cancer.The gene p16 and p15 have been assigned to this region.Both p16 and p15 are an inhibitor of cyclin D cdk4,cyclin D cdk6 complex and have been implicated in a wide variety of cancer types,including the germline of patients with familial melanoma.In order to investigate and compare the status of p16,p15 gene in primary tumors and cell lines,we examined 357 primary tumors and 29 cell lines derived from diverse tumor types.In addition to analysis of these primary tumors and cell lines,blood specimens from 91 patients either with sporadic multiple cancers or from cancer prone families were also analyzed.The data showed the following:1)Homozygous deletions of p16,p15 were comparatively rare and far less common than previously reported,although hemizygous deletions were observed in a significant fraction of many tumor types;2)the incidence of p16,p15 deletions(either homozygous deletions or heterozygous deletions)varied significantly among different tumor types;3)most deletions involved in both p16 and p15 genes;4)sequence variations in the coding sequence of p16,p15 were comparatively rare among these tumor types,though mutations and polymorphisms were identified;5)some tumors which showed LOH at 9p,containing p16 and p15 gene,did not show deletions or point mutations in the p16,p15 gene.6)In a subset of retinoblastoma and osteosarcoma where no Rb gene mutations were present a significant fraction was found to contain p16,p15 gene deletions.

Expression and significance of the polar regulation-associated protein in cholangiocarcinoma

Objective： To investigate the expressions of atypical protein kinase C = subtype （aPKC-I and E-cadherin in cholangiocarcinoma, and analyze molecular mechanisms of the invasion and metastasis of cholangiocarcinoma. Methods： The expressions of aPKC-I nd E-cadherin in 9 specimens of benign bile duct tissues and 35 specimens of cholangiocarcinoma were detected by EnVision immunohistochemistry, and their correlations to the clinicopathologic characteristics and invasion of cholangiocarcinoma were analyzed. Results： The positive rate of aPKC-I was significantly higher in cholangiocarcinoma than in benign bile duct tissues （68.6% vs. 11.1%, P = 0.006）, while the positive rate of E-cadherin was significantly lower in cholangiocarcinoma than in benign bile duct tissues （37.1% vs. 88.9%, P = 0.016）. aPKC-I expression was negatively correlated to E-cadherin expression （r = -0.287, P 〈 0.05）. aPKC-I expression was positively and E-cadherin expression was negatively correlated to the differentiation and invasion of cholangiocarcinoma （P 〈 0.05）. Conclusion： The expressions of aPKC-I and E-cadherin may reflect the differentiation and invasive potential of cholangiocarcinoma. As a polar regulation-associated protein, aPKC-I may play an important role in the invasion and metastasis of cholangiocarcinoma.

钙调蛋白与肿瘤的关系

钙调蛋白是一种广泛存在于体内,能与Ca++结合,并有细胞调节功能的蛋白质。钙调蛋白与Ca++结合后,形成许多酶的复合物,影响机体的生理生化过程。

Epigenetic regulation by polycomb group complexes:focus on roles of CBX proteins

Polycomb group （PCG） complexes are epigenetic regulatory complexes that conduct transcriptional repression of target genes via modifying the chromatin. The two best characterized forms of PCG complexes, polycomb repressive complexes 1 and 2 （PRC1 and PRC2）, are required for maintaining the sternness of embryonic stem cells and many types of adult stem cells. The spectra of target genes for PRCs are dynamically changing with cell differentiation, which is essential for proper decisions on cell fate during developmental processes, Chromobox （CBX） family proteins are canonical components in PRC1, responsible for targeting PRC1 to the chromatin. Recent studies highlight the function specifications among CBX family members in undifferentiated and differentiated stem cells, which reveal the interplay between compositional diversity and functional specificity of PRCI. In this review, we summarize the current knowledge about targeting and functional mechanisms of PRCs, emphasizing the recent breakthroughs related to CBX proteins under a number of physiological and pathological conditions.