Research Paper Advance Articles

Figure 5. SPINT2 induces senescence by inhibiting c-Met signaling. (A) Western blot analysis of phosphorylated c-Met (p-c-Met), total c-Met, SPINT2, and p21 protein expression in the RS model HDFs. (B) Western blot analysis of p-c-Met, c-Met, SPINT2, and p21 in the time-series OSIS model. (C) HDFs (DT2) were infected with recombinant lentivirus encoding SPINT2 cDNA for 4 days, followed by Western blot analysis. GFP-encoded recombinant lentivirus was used as a control. (D-E) HDFs (DT2) were transfected with siRNAs targeting negative control (NC) or c-Met (si-c-Met) for 4 days. (D) Western blot analysis of DNMT1, SPINT2, and p21 protein expression. (E) Quantification of SA-β-gal activity. ^**p < 0.01 vs. NC by Student’s t-test. (F) HDFs (DT2) were transfected with siRNAs targeting DNMT1 (siDNMT1) and/or SPINT2 (siSPINT2) for 4 days. Western blot analysis was performed. (G) M-stage HDFs (DT4) were transfected with siRNAs targeting SPINT2 (siSPINT2) for 4 days. E-stage HDFs were also used as control. Western blot analysis. (H) Heatmap presentation of differentially expressed c-Met signaling genes based on transcriptomic data from RS and OSIS models (GSE41714 and GSE80332, respectively). (I) Venn diagram depicting the overlap in deregulated c-Met signaling genes between the RS and OSIS models. Among these, 15 genes were commonly downregulated, and 19 genes were commonly upregulated. (J) HDFs (DT2) were transfected with c-Met siRNA (si-c-Met) for four days, followed by qRT-PCR analysis of c-Met target gene expression. ^**p < 0.01 vs. NC by Student’s t-test. (K) HDFs (DT2) were infected with recombinant lentivirus encoding SPINT2 cDNA for 4 days, followed by qRT-PCR analysis of c-Met target genes. GFP-encoded recombinant lentivirus was used as a control. ^**p < 0.01 vs. GFP by Student’s t-test. (L) Schematic diagram of early senescence modulation.