AIM: To assess whether the molecular markers of malignant tumors could improve the understanding of tumor characteristics, and to observe the characteristics of expression of cell cycle markers Ki-67 and cyclin A in e...AIM: To assess whether the molecular markers of malignant tumors could improve the understanding of tumor characteristics, and to observe the characteristics of expression of cell cycle markers Ki-67 and cyclin A in esophageal carcinoma and to analyze the relationship between proliferative activity of cancer cells and clinicopathological factors. METHODS: Seventy of surgically resected esophageal squamous cell carcinoma (SCC) were examined by immun-ohistochemistry utilizing commercially available antibodies. Nuclear staining was regarded as a positive result. At least 50 fields in each tumor and non-tumor section were evaluated at a medium power (×200) to determine the proportion of tumor cells and the staining intensity of nuclei in the entire sections. RESULTS: Ki-67 and cyclin A were only expressed in base cells of normal esophageal mucosa. The positive immuno-staining of nuclei of SCC was significantly higher than that in normal esophageal mucosa (t = 13.32 and t = 7.52, respectively, P<0.01). The distribution of positively stained was more diffuse and stronger in poorly differentiated SCC. Both Ki-67 and cyclin A expressions were related to histological grades of tumors (t = 3.5675 and t = 3.916; t = 2.13, respectively, P<0.05) but not to the sex and age of the patients, tumor size, lymphatic invasion, location, or stage grouping. CONCLUSION: The proliferative activity of cancer cells may be understood by immunohistochemistry of Ki-67 and cyclin A in Chinese patients with esophageal SCC. These cell cycle markers may serve as an indicator of cancer cell proliferation rate. The overexpression of cell cycle markers Ki-67 and cyclin A suggests the poor SCC differentiation in patients with esophageal carcinoma.展开更多
AIM: The role of Pancreatic and Duodenal Homeobox-1(PDX-1) as a major regulator of pancreatic development determines the function and phenotype of β cell. In this study, potential plasticity of liver cells into pancr...AIM: The role of Pancreatic and Duodenal Homeobox-1(PDX-1) as a major regulator of pancreatic development determines the function and phenotype of β cell. In this study, potential plasticity of liver cells into pancreatic endocrine cells induced by PDX-1 was evaluated.METHODS: Human hepatoma cell line HepG2 was stably transfected with mammalian expression plasmid pcDNA3-PDX encoding human PDX-1 gene. Ectopic expression of PDX-1 and insulin were detected by RT-PCR,Western blot and/or immunostaining. PDX-1+ HepG2 cells were transplanted under renal capsule of STZ-induced diabetic nude mice (n = 16) to examine the inducing effect in vivo.RESULTS: Exogenous PDX-1 transgene was proved to express effectively in HepG2 cell at both mRNA and protein levels. The expression of endogenous insulin and some βcell-specific differentiation markers and transcription factors were not induced in PDX-1+ HepG2 cells. When transplanted under renal capsule of STZ-induced diabetic nude mice, PDX-1+ HepG2 cells did not generate insulinproducing cells. These data indicated that stable transfected PDX-1 could not convert hepatoma cell line HepG2 to pancreatic cells in vitro or in vivo. Mature hepatocytes might need much more complicated or rigorous conditions to be shifted to insulin-producing cells.CONCLUSION: The expression of exogenous PDX-1 is not sufficient to induce relatively mature hepatocytes differentiating into insulin-producing cells.展开更多
Differential proteome profiles of human lung squamous carcinoma tissue compared to paired tumor-adjacent normal bronchial epithelial tissue were established and analyzed by means of immobilized pH gradient-based two-d...Differential proteome profiles of human lung squamous carcinoma tissue compared to paired tumor-adjacent normal bronchial epithelial tissue were established and analyzed by means of immobilized pH gradient-based two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) and matrix-assisted laser desorp-tion/ionization time of flight mass spectrometry (MALDI-TOF-MS). The results showed that well-resolved, reproducible 2-DE patterns of human lung squamous carcinoma and adjacent normal bronchial epithelial tissues were obtained under the condition of 0.75-mg protein-load. The average deviation of spot position was 0.733±0.101 mm in IEF direction, and 0.925±0.207 mm in SDS-PAGE direction. For tumor tissue, a total of 1241±88 spots were detected, 987±65 spots were matched with an average matching rate of 79.5%. For control, a total of 1190±72 spots were detected, and 875±48 spots were matched with an average matching rate of 73.5%. A total of 864±34 spots were matched between tumors and controls. Forty-three differential proteins were characterized: some proteins were related to oncogenes, and others involved in the regulation of cell cycle and signal transduc-tion. It is suggested that the differential proteomic approach is valuable for mass identification of differentially expressed proteins involved in lung carcinogenesis. These data will be used to establish human lung cancer proteome database to further study human lung squamous carcinoma.展开更多
基金Supported by the Key Medical Talent Foundation of Jiangsu Province, China, No. 2001-34 and 2002-15
文摘AIM: To assess whether the molecular markers of malignant tumors could improve the understanding of tumor characteristics, and to observe the characteristics of expression of cell cycle markers Ki-67 and cyclin A in esophageal carcinoma and to analyze the relationship between proliferative activity of cancer cells and clinicopathological factors. METHODS: Seventy of surgically resected esophageal squamous cell carcinoma (SCC) were examined by immun-ohistochemistry utilizing commercially available antibodies. Nuclear staining was regarded as a positive result. At least 50 fields in each tumor and non-tumor section were evaluated at a medium power (×200) to determine the proportion of tumor cells and the staining intensity of nuclei in the entire sections. RESULTS: Ki-67 and cyclin A were only expressed in base cells of normal esophageal mucosa. The positive immuno-staining of nuclei of SCC was significantly higher than that in normal esophageal mucosa (t = 13.32 and t = 7.52, respectively, P<0.01). The distribution of positively stained was more diffuse and stronger in poorly differentiated SCC. Both Ki-67 and cyclin A expressions were related to histological grades of tumors (t = 3.5675 and t = 3.916; t = 2.13, respectively, P<0.05) but not to the sex and age of the patients, tumor size, lymphatic invasion, location, or stage grouping. CONCLUSION: The proliferative activity of cancer cells may be understood by immunohistochemistry of Ki-67 and cyclin A in Chinese patients with esophageal SCC. These cell cycle markers may serve as an indicator of cancer cell proliferation rate. The overexpression of cell cycle markers Ki-67 and cyclin A suggests the poor SCC differentiation in patients with esophageal carcinoma.
基金the National Natural Science Foundation of China,No. 30240087 the National High Technology Research and Development Program of China, No. 2003AA205090
文摘AIM: The role of Pancreatic and Duodenal Homeobox-1(PDX-1) as a major regulator of pancreatic development determines the function and phenotype of β cell. In this study, potential plasticity of liver cells into pancreatic endocrine cells induced by PDX-1 was evaluated.METHODS: Human hepatoma cell line HepG2 was stably transfected with mammalian expression plasmid pcDNA3-PDX encoding human PDX-1 gene. Ectopic expression of PDX-1 and insulin were detected by RT-PCR,Western blot and/or immunostaining. PDX-1+ HepG2 cells were transplanted under renal capsule of STZ-induced diabetic nude mice (n = 16) to examine the inducing effect in vivo.RESULTS: Exogenous PDX-1 transgene was proved to express effectively in HepG2 cell at both mRNA and protein levels. The expression of endogenous insulin and some βcell-specific differentiation markers and transcription factors were not induced in PDX-1+ HepG2 cells. When transplanted under renal capsule of STZ-induced diabetic nude mice, PDX-1+ HepG2 cells did not generate insulinproducing cells. These data indicated that stable transfected PDX-1 could not convert hepatoma cell line HepG2 to pancreatic cells in vitro or in vivo. Mature hepatocytes might need much more complicated or rigorous conditions to be shifted to insulin-producing cells.CONCLUSION: The expression of exogenous PDX-1 is not sufficient to induce relatively mature hepatocytes differentiating into insulin-producing cells.
基金This work was supported by a grant from National 973 Project (2001CB5102) for Outstanding Scholars of New Era from the Ministry of Education of China (2002-48)+1 种基金 National Natural Science Foundation of China (30000028) the key research program from Sc
文摘Differential proteome profiles of human lung squamous carcinoma tissue compared to paired tumor-adjacent normal bronchial epithelial tissue were established and analyzed by means of immobilized pH gradient-based two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) and matrix-assisted laser desorp-tion/ionization time of flight mass spectrometry (MALDI-TOF-MS). The results showed that well-resolved, reproducible 2-DE patterns of human lung squamous carcinoma and adjacent normal bronchial epithelial tissues were obtained under the condition of 0.75-mg protein-load. The average deviation of spot position was 0.733±0.101 mm in IEF direction, and 0.925±0.207 mm in SDS-PAGE direction. For tumor tissue, a total of 1241±88 spots were detected, 987±65 spots were matched with an average matching rate of 79.5%. For control, a total of 1190±72 spots were detected, and 875±48 spots were matched with an average matching rate of 73.5%. A total of 864±34 spots were matched between tumors and controls. Forty-three differential proteins were characterized: some proteins were related to oncogenes, and others involved in the regulation of cell cycle and signal transduc-tion. It is suggested that the differential proteomic approach is valuable for mass identification of differentially expressed proteins involved in lung carcinogenesis. These data will be used to establish human lung cancer proteome database to further study human lung squamous carcinoma.
