Role of Peg10 in FAK-mediated CAM-DR in hepatocellular carcinoma

• Main Author: ZHANG Hai
• Format: Article
• Language: zho
• Published: Editorial Department of Journal of Clinical Hepatology 2015-02-01
• Series: Linchuang Gandanbing Zazhi
• Subjects: liver neoplasms; focal adhesion protein-tyrosine kinases; Peg10 gene; drug resistance; neoplasm; RNA; small interfering
• Online Access: http://www.lcgdbzz.org/qk_content.asp?id=6279&ClassID=11415232
• ISSN: 1001-5256; 1001-5256

ObjectiveTo preliminarily investigate the relationship of Peg10 with focal adhesion kinase (FAK)-mediated cell adhesion-mediated drug resistance (CAM-DR) in hepatocellular carcinoma (HCC), and to explore the underlying molecular mechanism. MethodsThe effects of 5-fluorouracil (5-Fu) and adriamycin (ADR) on the proliferation of LO2 cells, ADR-resistant human HCC cells BEL-7404/ADR (7404/ADR), and Peg10-silenced cells siRNA-BEL-7404/ADR (siRNA-7404/ADR) were examined by MTT assay. To build a tumor-bearing nude mouse model, 48 rats were randomly divided into six groups (n=8 each): groups A, C, and D were injected with 7404/ADR cells; groups B, E, and F were injected with siRNA-7404/ADR cells. For experimental treatments, groups A and B revived saline by intravenous injection through the tail vein; groups C and E were given 5-Fu; groups D and F received ADR by intravenous injection through the tail vein; tumor mass volume was measured after injection. Peg10 mRNA expression was assayed by RT-PCR, and PEG10, p-FAK, p-JNK, p-ERK, and p-P38 protein expression was assayed by Western blotting. ResultsThe 24-h IC50 values of ADR and 5-Fu on SiRNA-7404/ADR were both significantly reduced compared with those on 7404/ADR (t=7.641 and 7.560, respectively; both P＜0.01). Significantly smaller tumor mass volume was observed in groups B, C, and D than in group A (P＜0.05), and in groups E and F than in group B (P＜0.01). Additionally, tumor mass volume was significantly different between groups E and C as well as between groups F and D (P＜0.05). PEG10 mRNA was rarely expressed in groups B, E, and F. Compared with that in group A, PEG10 mRNA expression in groups C and D was relatively reduced. PEG10 protein was rarely expressed in group B and its expression level significantly differed from that in group A (P＜0.01). Additionally, there were statistically significant differences in p-FAK, p-JNK, p-ERK, and p38MAPK protein expression between groups B and A (P＜0.05). In groups C and D, PEG10, p-FAK, p-JNK, p-ERK, and p38MAPK protein expression was significantly reduced compared with that in group A (P＜0.05). Significant differences in p-FAK, p-JNK, p-ERK, and p38MAPK protein expression also occurred in groups E and F compared with group B (P＜0.01). Moreover, there were significant differences in PEG10, p-FAK p-JNK, p-ERK, and p38MAPK protein expression between groups C and E as well as between groups D and F (P＜0.01). ConclusionThe inactivation of PEG10 can increase the sensitivity of ARD-resistant cell line BEL-7404 to 5-Fu and ARD. The underlying mechanism is possibly related to down-regulation of p-FAK, p-JNK, p-ERK, and p38MAPK expression.