Background Mutant C57BL/6 mouse with corneal opacity (B6-Co) appears eye open at birth (EOB) phenotype,which is a good animal model in the study of developmental mechanism of eyelid.Investigating the relationship between serum response factor (SRF) and EOB phenotype can provide theoretical support for the research on the mechanism of innate defects in eyelid development in humans.Objective This study was to assess the dynamic expressions of SRF in eyelid of embryonic B6-Co mouse.Methods Total RNA was extracted from B6 and B6-Co mice eyelid tissue at embryonic day 16.5 (E16.5 d),E17.5 d and E18.5 d.The relative expression levels of SRF mRNA and protein in the eyelid tissue of B6 and B6-Co embryonic mice were assayed by real-time quantitative PCR and Western blot,respectively.In situ expressions of SRF protein in eyelid of B6-Co mice and B6 mice were detected using immunofluorescence technique.The use and care of the animals complied with the Regulation for the Administration of Affair Concerning Experimental Animals of Nantong University.Results The relative expression levels ofSRF mRNA in the eyelids were 0.41±0.06 and 0.24±0.17 in E16.5 d and E17.5 d of B6-Co mice,showing a significant decline in comparison with 1.03 ±0.17 and 1.01 ±0.09 in the B6 mice (P =0.025,0.017).The expression levels of SRF protein in the eyelids of E16.5 d and E17.5 d B6-Co mice were 0.08±0.01 and 0.08± 0.01,which were significantly lower than 0.12 ±0.03 and 0.13 ± 0.02 of B6 mice (P =0.036,0.024).However,there were no significant differences in the expression levels of SRF mRNA and protein in E18.5 d between the B6-Co mice and B6 mice (P =0.387,0.774).Immunofluorescence assay displayed that SRF was expressed in the keratinocytes of eyelids in both mice,but the fluorescence intensity was weaker in the B6-Co mice.Conclusions SRF probably interrupts the developing process of eyelid in early embryo of B6-Co mice.

Objective To investigate the effect of MACC1 on RSL3-induced ferroptosis in colorectal cancer cells and explore its molecular mechanism.Methods MACC1 expression was detected in SW620,HCT116,LOVO and RKO cells using Western blotting.The effects of different concentrations of RSL3(an inducer of ferroptosis)or Fer-1(an inhibitor of ferroptosis)alone,or 10 μmol/L RLS3 combined with 10 μmol/L Fer-1,on viability of SW620 cells were examined using MTT assay.The survival of SW620 cells with mRNA interference of MACC1 was analyzed following treatment with RSL3,and RT-qPCR and Western blotting were performed to detect the changes in MACC1 expressions after RSL3 treatment at different concentrations and the changes in GPX4 expression after MACC1 knockdown.Flow cytometry and laser confocal microscopy were used to analyze the changes in ROS-induced lipid peroxidation in SW620 cells after MACC1 knockdown.Results SW620 cells had the highest MACC1 expression among the 4 colorectal cancer cell lines.Treatment with RSL3 significantly inhibited the viability of SW620 cells in a dose-dependent manner,while Fer-1 did not significantly affect the survival of SW620 cells.RSL3 alone reduced SW620 cell survival by 50%(P<0.01),and the combined treatment with RSL3 and Fer-1 caused no significant changes in cell survival(P>0.05).Treatment with RSL3 concentration-dependently suppressed MACC1 expressions at both the mRNA and protein levels in SW620 cells(P<0.01).MACC1 knockdown obviously enhanced the cytotoxic effect of RSL3,inhibited the expression of GPX4,and increased ROS-induced lipid peroxidation in SW620 cells(P<0.05).Conclusion MACC1 knockdown enhances RSL3-induced ferroptosis in cultured colorectal cancer cells by inhibiting the expression of GPX4.

Objective To investigate the effect of MACC1 on RSL3-induced ferroptosis in colorectal cancer cells and explore its molecular mechanism.Methods MACC1 expression was detected in SW620,HCT116,LOVO and RKO cells using Western blotting.The effects of different concentrations of RSL3(an inducer of ferroptosis)or Fer-1(an inhibitor of ferroptosis)alone,or 10 μmol/L RLS3 combined with 10 μmol/L Fer-1,on viability of SW620 cells were examined using MTT assay.The survival of SW620 cells with mRNA interference of MACC1 was analyzed following treatment with RSL3,and RT-qPCR and Western blotting were performed to detect the changes in MACC1 expressions after RSL3 treatment at different concentrations and the changes in GPX4 expression after MACC1 knockdown.Flow cytometry and laser confocal microscopy were used to analyze the changes in ROS-induced lipid peroxidation in SW620 cells after MACC1 knockdown.Results SW620 cells had the highest MACC1 expression among the 4 colorectal cancer cell lines.Treatment with RSL3 significantly inhibited the viability of SW620 cells in a dose-dependent manner,while Fer-1 did not significantly affect the survival of SW620 cells.RSL3 alone reduced SW620 cell survival by 50%(P<0.01),and the combined treatment with RSL3 and Fer-1 caused no significant changes in cell survival(P>0.05).Treatment with RSL3 concentration-dependently suppressed MACC1 expressions at both the mRNA and protein levels in SW620 cells(P<0.01).MACC1 knockdown obviously enhanced the cytotoxic effect of RSL3,inhibited the expression of GPX4,and increased ROS-induced lipid peroxidation in SW620 cells(P<0.05).Conclusion MACC1 knockdown enhances RSL3-induced ferroptosis in cultured colorectal cancer cells by inhibiting the expression of GPX4.