Figure 2
From: Targeting SRPK1 to control VEGF-mediated tumour angiogenesis in metastatic melanoma
SRPK1 regulates pro-angiogenic VEGF expression in melanoma cells. Serum-starved A375, Omm2.5, Mel270 and 92.1 cells, treated with 5 μ M SRPIN340 before IGF-1 administration (100 nM) were stained for (A) SRSF1 (red) or (B) SRPK1 (red) and co-stained for Hoechst (blue). (A) The majority of SRSF1 staining observed was nuclear, but an increase in nuclear intensity following IGF-1 treatment was observed in A375 and Mel270 cells. Pretreatment with SRPIN340 prevented the IGF-1-induced increase in SRSF1 nuclear intensity in Mel270 cells only. #P<0.05. (B) SRPK1 staining was mainly cytoplasmic but nuclear intensity was increased following IGF-1 treatment; SRPIN340 was unable to reverse this response. Scale bar, 10 μm. **P<0.01. (C) Twenty-four hours after inhibitor treatment (1–10 μM) RNA was extracted and cDNA was made for PCR. Treatment with SRPIN340 reduced the expression of VEGF165 relative to GAPDH control in all tested cell lines. Water (W) and sample without reverse transcriptase (–RT) were used as negative controls. (D) Forty-eight hours after treatment, protein was extracted and assayed for total VEGF and VEGFxxxb by ELISA. The expression of pro-angiogenic VEGF (VEGFxxx) was reduced following 10 μ M SRPIN340 in A375, Omm2.5 and 92.1 cells (one-way ANOVA, Bonferroni post hoc. *P<0.05). Arrows show non-nuclear-stained cells. NS, not significant. The full colour version of this figure is available at British Journal of Cancer online.
