Research Paper Volume 13, Issue 3 pp 3554—3572

ESRP1 regulates alternative splicing of CARM1 to sensitize small cell lung cancer cells to chemotherapy by inhibiting TGF-β/Smad signaling

Global regulation of the transcriptome by ESRP1 in SCLC chemoresistance-related genes. (A) Quantification of the different AS events affected by ESRP1. (B) Gene ontology of ESRP1-regulated AS targets. Fisher exact p values were plotted for each enriched functional category. (C) Functional association network of ESRP1-regulated AS targets. The genes in (C) were analyzed using the STRING database, and subgroups are marked according to their functions. (D) Correlation between the relative changes in Exon inclusion ratio values observed by RNA-seq vs RT-PCR confirmation. (E) Validation of different types of ESRP1-regulated AS events by semiquantitative RT-PCR using H69AR cells transfected with ESRP1 or control vectors. The mean ± SD of Exon inclusion Ratio from three experiments were plotted. (F) The expression of CARM1 pre-mRNAs with ESRP1 was detected by RNA immunoprecipitation (RIP) assay in H69 cells. (G) Representative ethidium bromide stained agarose gel photo showing expression of CARM1FL and CARM1ΔE15 in chemoresistant and chemosensitive cells. (H) Representative ethidium bromide stained agarose gel photo showing expression of CARM1FL and CARM1ΔE15 after overexpressing ESRP1 in H69AR cells. *, pp p p

Figure 4. Global regulation of the transcriptome by ESRP1 in SCLC chemoresistance-related genes. (A) Quantification of the different AS events affected by ESRP1. (B) Gene ontology of ESRP1-regulated AS targets. Fisher exact p values were plotted for each enriched functional category. (C) Functional association network of ESRP1-regulated AS targets. The genes in (C) were analyzed using the STRING database, and subgroups are marked according to their functions. (D) Correlation between the relative changes in Exon inclusion ratio values observed by RNA-seq vs RT-PCR confirmation. (E) Validation of different types of ESRP1-regulated AS events by semiquantitative RT-PCR using H69AR cells transfected with ESRP1 or control vectors. The mean ± SD of Exon inclusion Ratio from three experiments were plotted. (F) The expression of CARM1 pre-mRNAs with ESRP1 was detected by RNA immunoprecipitation (RIP) assay in H69 cells. (G) Representative ethidium bromide stained agarose gel photo showing expression of CARM1FL and CARM1ΔE15 in chemoresistant and chemosensitive cells. (H) Representative ethidium bromide stained agarose gel photo showing expression of CARM1FL and CARM1ΔE15 after overexpressing ESRP1 in H69AR cells. *, p<0.05; **, p <0.01; ***, p <0.001; ****, p <0.0001.