Morphology and microRNA expression profiles of drug-resistant cells in hepatocellular carcinoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To compare morphological differences of three drug-resistant hepatocellular carcinoma (HCC) cell subclones (Huh-7/ADM, Huh-7/CBP, Huh-7/MMC) and their parental Huh-7 cell line, to analyze differential microRNA (miRNA) expression profiles in these cells and, finally to screen for the abnormal expressed miRNAs in drug-resistant HCC cells.</p><p><b>METHODS</b>Cellular morphology was observed by histology and transmission electron microscopy. MiRNA microarray was used to analyze the differential miRNA expression profiles in these cells (Huh-7, Huh-7/ADM, Huh-7/CBP, Huh-7/MMC) followed by real time quantitative PCR validation.</p><p><b>RESULTS</b>The drug-resistant cells had more intracytoplasmic organelles and were larger in size along with increased cytological pleomorphism than the parental Huh-7 cells. Compared with the parental Huh-7 cells, 32 simultaneously up-regulated and 22 down-regulated miRNAs were found in three drug-resistant cells. Up-regulation of miR-15a, miR-16, miR-27b, miR-30b, miR-146a, miR-146b-5p, miR-181a, miR-181d and miR-194 was verified by RT-qPCR.</p><p><b>CONCLUSION</b>Drug-resistant HCC cells have abnormal expressed miRNAs, which may be explored to further investigate the association of miRNA expressions with multidrugs resistance in HCC.</p>

Improved sensitivity of gastric carcinoma cells to fluorouracil-related drugs by transfection of thymidine phosphorylase gene / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between the expression of thymidine phosphorylase (TP) and the sensitivity of gastric carcinoma to 5-fluorouracil (5-FU) and its prodrugs.</p><p><b>METHODS</b>Gastric carcinoma cell line AGS was transfected with recombinant plasmid pEGFP-N1-TP or control plasmid pEGFP-N1 by lipofectamin 2000. The expression of green fluorescence labeled protein was observed under fluorescence microscope. Positive clones AGS-p and AGS-pTP were selected by G418 treatment. Expression of TP protein and mRNA was detected by immunocytochemistry and RT-PCR, respectively. Drug sensitivity to 5-FU and its prodrugs was assessed by MTT assay.</p><p><b>RESULTS</b>Cell clones with the expression of green fluorescent protein (AGS-p) and a clone with TP and green fluorescent fusion protein (AGS-pTP) were established. Immunostaining of TP protein was strongly positive in AGS-pTP and negative in AGS-p and AGS. The expression of TP mRNA was significantly higher in AGS-pTP (0.8090 ± 0.0450) than that in AGS (0.0490 ± 0.0046) and AGS-p (0.0610 ± 0.0069; P < 0.01). The sensitivity to doxifluridine and capecitabine in AGS-pTP was significantly increased, as compared with that in AGS-p. IC50 values of AGS-pTP to doxifluridine and capecitabine were estimated 1.7 folds and 2.2 folds as much as that of AGS-p, respectively. The sensitivity to 5-FU was not different between AGS-pTP and AGS-p.</p><p><b>CONCLUSIONS</b>Enhancement of TP expression improves the sensitivity of gastric carcinoma cells to doxifluridine and capecitabine. But it does not affect the sensitivity to 5-FU.</p>