Research Paper Volume 13, Issue 10 pp 13405—13420

Inhibition of CXCR2 plays a pivotal role in re-sensitizing ovarian cancer to cisplatin treatment

Silencing CXCR2 expression reduces EMT marker proteins SLUG and SNAIL in ACRP and seems to modulate PI3K/AKT/mTOR, but not MEK/ERK, pathway. Western blot assays were performed to investigate the expression of EMT marker proteins in ACRP and A2780 lines, as follow: i) CN cells (10; II) siRNA CXCR2 KD cells; iii) cells treated with SB225002. 50μ of protein were loaded into SDS-PAGE gels, proteins were separated by electrophoresis and blotted with the primary antibodies of interest. (A) Representative figure of the blots performed for each marker and different treatments, (B) SNAIL protein expression was significantly decreased in ACRP CXCR2 KD cells vs. ACRP wild type, but not in A2780 cells. (C) SLUG protein expression was significantly lower in ACRP CXCR2 KD cells with comparison to its wild-type counterpart, however not in A2780 cells. (D) β-Catenin and (E) Vimentin did not present significant statistical difference amongst the conditions studied. Moreover, when we seek to correlate pro-carcinogenic signaling pathways related to CXCR2, no statistic significant difference were noted both in (F) pAKT/AKT and (G) pERK/ERK pathways. It is worth note to address the biologic tendency of the CXCR2 KD models, but not the treatment of cells with SB225002, to inactivate PI3K/AKT/mTOR, but not MEK/ERK pathway (p= 0.7 and p=0.09 in ACRP and A2780, respectively). Data were analysed by two-way ANOVA followed the Bonferroni post- test. β-actin was used as a normalization control of the experiments. *p

Figure 8. Silencing CXCR2 expression reduces EMT marker proteins SLUG and SNAIL in ACRP and seems to modulate PI3K/AKT/mTOR, but not MEK/ERK, pathway. Western blot assays were performed to investigate the expression of EMT marker proteins in ACRP and A2780 lines, as follow: i) CN cells (10; II) siRNA CXCR2 KD cells; iii) cells treated with SB225002. 50μ of protein were loaded into SDS-PAGE gels, proteins were separated by electrophoresis and blotted with the primary antibodies of interest. (A) Representative figure of the blots performed for each marker and different treatments, (B) SNAIL protein expression was significantly decreased in ACRP CXCR2 KD cells vs. ACRP wild type, but not in A2780 cells. (C) SLUG protein expression was significantly lower in ACRP CXCR2 KD cells with comparison to its wild-type counterpart, however not in A2780 cells. (D) β-Catenin and (E) Vimentin did not present significant statistical difference amongst the conditions studied. Moreover, when we seek to correlate pro-carcinogenic signaling pathways related to CXCR2, no statistic significant difference were noted both in (F) pAKT/AKT and (G) pERK/ERK pathways. It is worth note to address the biologic tendency of the CXCR2 KD models, but not the treatment of cells with SB225002, to inactivate PI3K/AKT/mTOR, but not MEK/ERK pathway (p= 0.7 and p=0.09 in ACRP and A2780, respectively). Data were analysed by two-way ANOVA followed the Bonferroni post- test. β-actin was used as a normalization control of the experiments. *p<0.022, **p<0.005. N=3.