MiR-124 suppresses the proliferation of human prostate cancer PC3 cells by targeting PKM2 / 中华男科学杂志

<p><b>OBJECTIVE</b>To explore the mechanism of miR-124 inhibiting the proliferative activity of prostate cancer PC3 cells.</p><p><b>METHODS</b>Luciferase reporter gene assay was used to examine the specific binding ability of miR-124 to PKM2 mRNA 3'-UTR. After miR-124 was transfected mimic to PC3 cells, the expression levels of PKM2 mRNA and protein were detected by real-time fluorescence quantitative PCR (qRT-PCR) and Western blot, respectively. The effects of miR-124 mimic and PKM2 siRNA on the proliferative activity of the PC3 cells were determined by MTT assay.</p><p><b>RESULTS</b>The expressions of PKM2 mRNA and protein were upregulated (5.12 +/- 0.35) times and (4.05 +/- 0.20) times respectively in the PC3 cells as compared with those in the RWPE-1 cells (P < 0.05). Luciferase reporter gene assay demonstrated that miR-124 targeted PKM2 3'-UTR. At 24 hours after transfection with miR-124 mimic, the PKM2 protein expression in the PC3 cells was downregulated (0.16 +/- 0.04) times (P < 0.05), while the PKM2 mRNA level was not changed significantly (P > 0.05), as compared with the control group. MTT assay showed that both miRNA-124 mimic and PKM2 siRNA could inhibit the proliferation of the PC3 cells, but the former exhibited a greater inhibitory effect than the latter. After transfection with miR-124 mimic and PKM2 siRNA, the cell growth rates were (66.20 +/- 5.10)% vs (82.10 +/- 6.35)% at 24 hours (P < 0.05) and (49.34 +/- 2.37)% vs (70.10 +/- 5.80)% at 48 hours (P < 0.05).</p><p><b>CONCLUSION</b>miR-124 can suppress the proliferation of PC3 cells by regulating the PKM2 gene.</p>

Construction of a tissue engineering skin with epidermal stem cells / 中华整形外科杂志

<p><b>OBJECTIVE</b>To constitute a composite skin substitute that can proliferate well with epidermal stem cells and fibroblasts on collagen sponge.</p><p><b>METHODS</b>Epidermal stem cells were selected by rapid attachment to collagen IV for 10-15 min and cultured on 3T3 feeder layers. Collagen was extracted from rat tail. The matrix lattice was fabricated by freeze-dryer and cross-linked with glutaraldehyde. Fibroblasts were inoculated on collagen sponge and cultured for 4 days prior to inoculation of epidermal stem cells to construct composite skin substitute. The composite skin substitute were examined by means of histology, immunohistochemistry and electron microcopy, the histologic appearance was similar to that of normal epidermis.</p><p><b>RESULTS</b>The epidermal stem cells formed large colonies at 7-8 days, expressed K19 antigen. The percentages of cells at G0/G1 phase of cell cycle and the percentage of alpha6 briCD71dim cells in ESC groups were higher than those in the control group. The skin substitute had epidermis and dermis, the histologic appearance was similar to that of normal skin. The artificial skin expressed keratin antigen by immunocytochemical methods.</p><p><b>CONCLUSIONS</b>Epidermal stem cells proliferated well and differentiated properly on this artificial skin dermis which contained fibroblasts. It seemed that the composite skin to be a good equivalent.</p>