The expression of B-cell translocation gene 2 in diethylnitrosamine-induced primary hepatocellular carcinoma rat model / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the expression and role of B-cell translocation gene 2(BTG2) in the carcinogenesis of hepatocellular carcinoma (HCC).</p><p><b>METHODS</b>Modified Diethylnitrosamine (DEN)-induced primary hepatocellular carcinoma rat model was established. The expression of BTG2, p53 and cyclinD1 was detected by RT-PCR, western blot and immunohistochemistry.</p><p><b>RESULTS</b>The BTG2 protein was predominantly localized in the nucleus, with faint cytoplasmic staining in normal liver cells; however, it is mainly a cytoplasmic protein in HCC cells. BTG2 was over-expressed during the early stage after DEN treatment, the expression level peaked at 5 weeks and then it gradually decreased to the normal level after 16 weeks. The expression of cyclin D1 and cyclin E was increased gradually after DEN treatment, and peaked at 16 weeks and 5 weeks respectively. A significant increase in p53 was not observed until 5 weeks after DEN treatment, and it gradually decreased after 16 weeks.</p><p><b>CONCLUSIONS</b>Decreased expression of BTG2 may be an important step in carcinogenesis of HCC. BTG2 may positively regulate p53 expression and negatively regulate cyclin D1 expression in the carcinogenesis of HCC.</p>

The expression of Tec and the level of its phosphorylation in primary hepatic carcinomas / 中华肝脏病杂志

<p><b>OBJECTIVES</b>To detect the expressions of Tec tyrosine kinase in hepatocellular carcinoma and the levels of phosphorylation of tyrosine kinase in liver cancer tissues, paracancerous tissues and normal liver tissues and to find the significance of their differences.</p><p><b>METHODS</b>200 specimens of tissues, including liver cancer tissues, surrounding liver tissues not more than 1.5 cm from the cancers, and normal liver tissues were investigated for Tec protein expression and Tec phosphorylation by tissue microarrays and immunohistochemistry (SP method).</p><p><b>RESULTS</b>The positive immunohistochemical stainings of Tec in cancerous tissues and non-cancerous tissues showed no obvious differences, nevertheless, the immunostaining levels in liver cancer tissues were much higher than in non-cancerous tissues and they correlated with the grading of tumors (P < 0.05). The phosphorylation of Tec was significantly expressed in liver cancer tissues (73%) in comparison with other tissues (42%, 10% both P < 0.05), but it did not correlate with any clinicopathological characteristics.</p><p><b>CONCLUSION</b>Overexpression of Tec is associated with the tumorigenesis and development of liver cancer; inhibiting Tec or degrading Tec phosphorylation directly might affect the progression of liver cancer.</p>

Effect of adenoviral N-methylpurine DNA glycosylase overexpression on chemosensitivity of human osteosarcoma cells / 中华病理学杂志

<p><b>OBJECTIVE</b>The overexpression of N-methylpurine DNA glycosylase (MPG) may imbalance the DNA base excision repair (BER) to sensitize tumor cells to current DNA damage chemotherapy. In an effort to improve the efficacy of cancer chemotherapy, we have constructed adenoviral vector of MPG, to study its ability to sensitize human osteosarcoma cell HOS to DNA damage agents.</p><p><b>METHODS</b>The adenoviral infection and MPG expression, as well as enzyme activity were determined by flow cytometry, Western blot, and HEX labeled oligonucleotide-based assay respectively. The cell survival/proliferation was measured using MTS, SRB, and [(3)H] thymidine incorporation assay. Apoptosis cell death was assayed by flow cytometry after treatment using phycoerythin (PE)-conjugated Annexin V and 7-amino-actinomycin (7-AAD).</p><p><b>RESULTS</b>A 10 MOI of recombinant nonreplicating adenovirus was found to infect more than 90% of HOS cells within 24 hours by EGFP fluorescence, in which the MPG overexpression and MPG enzyme activity were also detected. The MPG overexpression HOS cells were significantly more sensitive to the DNA damage agents, including MMS, MNNG, and TMZ, with changes in the IC50 of 6.0, 4.5, and 2.5 fold respectively.</p><p><b>CONCLUSIONS</b>These data establish transient MPG overexpression as a potential therapeutic approach for increasing HOS cellular sensitivity to DNA damage agent chemotherapy.</p>

Characteristic and clinicopathologic significance of lymphangiogenesis in colorectal cancer / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the distribution patterns and proliferative activity of lymphatic vessels in colorectal carcinomas (CRC) and their relationship with tumor metastasis and disease prognosis.</p><p><b>METHODS</b>The microlymphatic density (MLD) and microvascular density in tumoral and non-tumoral areas of 96 cases of CRC were evaluated by immunohistochemistry, using monoclonal antibodies for podoplanin and CD34 respectively. The Ki-67 expression of the lymphatic and blood vessels was detected by double-labeling immunohistochemistry. The relationship between MLD and clinicopathologic features and prognosis was analyzed.</p><p><b>RESULTS</b>The lymph vessels at central and superficia1 portions of CRC often had a reticular architecture with numerous tiny and ill-defined lumina, while those at the tumor borders had large and open lumina. The MLD at tumor borders (51.2 +/- 25.5) was significantly higher than that in normal colorectal mucosa (29.4 +/- 9.0) and other portions of CRC (P < 0.01). The Ki-67 labeling index of the lymphatic lining cells at tumor borders (0.23 +/- 0.17) was significantly higher than that in other portions of CRC (P < 0.05). The MLD significantly correlated with lymphatic involvement by tumor cells, regional lymph node metastasis and distant metastasis (P < 0.01). The 5-year survival rate was also significantly lower in patients with high MLD (P < 0.05).</p><p><b>CONCLUSIONS</b>Neolymphatic vessels are commonly seen in CRC, especially at tumor borders. High MLD at tumor borders is associated with metastasis. The detection of MLD at tumor borders may thus be useful in predicting lymph node metastasis and prognosis in patients with CPC.</p>

Microvessel quantitation and VEGF expression in colorectal carcinoma an d metastatic tissues / 第三军医大学学报

Objective　To explore the relationship between angiogenesis and tumor metastasis and prognosis by studying the angiogen esis in colorectal carcinoma tissues and metastasized tissues. Me thods　The microvessel density (MVD) and the expression of vascular endo thelial growth factor (VEGF) were studied with immunohistochemical assays in 15 samples of colorectal carcinoma with lymph node and liver metastasis, 20 specime ns of colorectal carcinoma without metastasis. Normal rectal mocosal tissues wer e taken from 10 cases of colorectal carcinoma with metastasis and 10 without.Re sults　The MVD was obviously higher in the cases of colorectal carcinoma with or without metastasis than in normal rectal tissues, and that in those wit h metastasis was higher than that of those without. The MVD was significantly hi gher in those positive to VEGF staining than those negative in colorectal carcin oma tissues and metastasized tumors. Conclusion　The MVD and VEG F expression can be regarded as indexes for tumor metastasis and prognosis in co lorectal carcinoma.

Microvessel quantitation and VEGF expression in colorectal carcinoma an d metastatic tissues / 第三军医大学学报

Objective　To explore the relationship between angiogenesis and tumor metastasis and prognosis by studying the angiogen esis in colorectal carcinoma tissues and metastasized tissues. Me thods　The microvessel density (MVD) and the expression of vascular endo thelial growth factor (VEGF) were studied with immunohistochemical assays in 15 samples of colorectal carcinoma with lymph node and liver metastasis, 20 specime ns of colorectal carcinoma without metastasis. Normal rectal mocosal tissues wer e taken from 10 cases of colorectal carcinoma with metastasis and 10 without.Re sults　The MVD was obviously higher in the cases of colorectal carcinoma with or without metastasis than in normal rectal tissues, and that in those wit h metastasis was higher than that of those without. The MVD was significantly hi gher in those positive to VEGF staining than those negative in colorectal carcin oma tissues and metastasized tumors. Conclusion　The MVD and VEG F expression can be regarded as indexes for tumor metastasis and prognosis in co lorectal carcinoma.