AIM To comparatively investigate the cellular and molecular characteristics of low-grade slightly elevated adenomas and polypoid adenomas.METHODS Colorectal tumors were collected from 24 patients with slightly elevate...AIM To comparatively investigate the cellular and molecular characteristics of low-grade slightly elevated adenomas and polypoid adenomas.METHODS Colorectal tumors were collected from 24 patients with slightly elevated adenomas and 23 patients with polypoid adenomas. five commonly mutated genes(APC, BRAf, KRAS, NRAS, and PIK3CA) were selected for mutational analysis. Paraffin-embedded tumor sections were used to calculate the apoptotic index(AI) and Ki-67 labeling index(KLI). Two pure colorectal epithelial cell lines were created by pooling the slightly elevated and polypoid tumors. western blots, luciferase assays for β-catenin-T-cell factor protein/β-cateninlymphoid enhancer factor(β-catenin-TCf/LEf)-driven transcriptional activity, and caspase activity assays were conducted on the two cell lines.RESULTS Slightly elevated lesions showed a significantly lower APC mutational frequency and a significantly higher KRAS mutational frequency(both P < 0.05). Slightly elevated lesions showed a significantly lower AI(P < 0.05). β-catenin and β-catenin-TCf/LEf-driven transcriptional activity was significantly upregulated in slightly elevated lesions(both P < 0.05). In slightly elevated lesions, c-Myc was significantly downregulated, while cyclin D1 was significantly upregulated(both P < 0.05). β-catenin-TCf/LEf-driven transcriptional activity was negatively correlated with c-Myc(ρ =-0.78). Slightly elevated lesions displayed significant Bcl-2 and Bcl-x L upregulation(both P < 0.05) along with significant decreases in caspase-9 and caspase-3 activity(both P < 0.05). c-Myc was negatively correlated with Bcl-2 and Bcl-x L(ρ =-0.74 and-0.78, respectively).CONCLUSION The lower apoptotic activity of low-grade slightly elevated adenomas can be partly attributed to upregulated β-catenin pathway activity and downregulated c-Myc expression.展开更多
By using silver colloid staining technique,nucleolar organizer region-associated proteins(AgNORs)were studied quantatively in paraffin sections of 12 casesof polypoid adenomas,10 cases of villous adenomas,22 cases of ...By using silver colloid staining technique,nucleolar organizer region-associated proteins(AgNORs)were studied quantatively in paraffin sections of 12 casesof polypoid adenomas,10 cases of villous adenomas,22 cases of colonadenocarcinomas,and 10 cases of normal colonic mucosa as control.The resultsshowed that the mean number of AgNORs per nucleus in the villous adcnoma was similarto that of adenocaranoma,which significantly exceeded those of the normal mucosa andthe polypoid adenoma.The granules of AgNORs in adcnocarcinoma were much largerand more irregular in sizc and shape.It is suggested that benign villous adenoma is akind of lesion between polypoid adenoma and adenocarcinoma,and AgNOR techniquemay be very helpful in differential diagnosis of colon tumors.展开更多
基金Supported by the Yongchuan Chongqing Medical University Hospital Fund,no.YJYB2012009
文摘AIM To comparatively investigate the cellular and molecular characteristics of low-grade slightly elevated adenomas and polypoid adenomas.METHODS Colorectal tumors were collected from 24 patients with slightly elevated adenomas and 23 patients with polypoid adenomas. five commonly mutated genes(APC, BRAf, KRAS, NRAS, and PIK3CA) were selected for mutational analysis. Paraffin-embedded tumor sections were used to calculate the apoptotic index(AI) and Ki-67 labeling index(KLI). Two pure colorectal epithelial cell lines were created by pooling the slightly elevated and polypoid tumors. western blots, luciferase assays for β-catenin-T-cell factor protein/β-cateninlymphoid enhancer factor(β-catenin-TCf/LEf)-driven transcriptional activity, and caspase activity assays were conducted on the two cell lines.RESULTS Slightly elevated lesions showed a significantly lower APC mutational frequency and a significantly higher KRAS mutational frequency(both P < 0.05). Slightly elevated lesions showed a significantly lower AI(P < 0.05). β-catenin and β-catenin-TCf/LEf-driven transcriptional activity was significantly upregulated in slightly elevated lesions(both P < 0.05). In slightly elevated lesions, c-Myc was significantly downregulated, while cyclin D1 was significantly upregulated(both P < 0.05). β-catenin-TCf/LEf-driven transcriptional activity was negatively correlated with c-Myc(ρ =-0.78). Slightly elevated lesions displayed significant Bcl-2 and Bcl-x L upregulation(both P < 0.05) along with significant decreases in caspase-9 and caspase-3 activity(both P < 0.05). c-Myc was negatively correlated with Bcl-2 and Bcl-x L(ρ =-0.74 and-0.78, respectively).CONCLUSION The lower apoptotic activity of low-grade slightly elevated adenomas can be partly attributed to upregulated β-catenin pathway activity and downregulated c-Myc expression.
文摘By using silver colloid staining technique,nucleolar organizer region-associated proteins(AgNORs)were studied quantatively in paraffin sections of 12 casesof polypoid adenomas,10 cases of villous adenomas,22 cases of colonadenocarcinomas,and 10 cases of normal colonic mucosa as control.The resultsshowed that the mean number of AgNORs per nucleus in the villous adcnoma was similarto that of adenocaranoma,which significantly exceeded those of the normal mucosa andthe polypoid adenoma.The granules of AgNORs in adcnocarcinoma were much largerand more irregular in sizc and shape.It is suggested that benign villous adenoma is akind of lesion between polypoid adenoma and adenocarcinoma,and AgNOR techniquemay be very helpful in differential diagnosis of colon tumors.
