CORO2A/NF-κB/FANCD2 Pathway Regulates DNA Damage Repair And Carboplatin Sensitivity In Triple Negative Breast Cancer Cells

Breast cancer is a severe health risk for women,and triplenegative breast cancer(TNBC)is the deadliest subtype of breast cancer with limited treatment options and poor prognosis.Pathologic complete remission(p CR)with neoadjuvant chemotherapy for TNBC is closely related to prognosis,and the use of carboplatin chemotherapy significantly improves the neoadjuvant p CR rate in TNBC patients.Still,significant individual differences limit the precise treatment of TNBC with carboplatin.Based on the previous bioinformatics analysis results that COR2 A was differentially expressed in TNBC and negatively correlated with the prognosis of TNBC patients,this project explores the effect of COR2 A expression on carboplatin sensitivity in TNBC cells.It reveals its molecular mechanism,providing a new biomarker and research basis for realizing precise treatment of TNBC patients with carboplatin.Objective: To reveal and elucidate that CORO2 A regulates the NF-κB/FANCD2 pathway to mediate cellular DNA damage repair and affects the sensitivity of TNBC cells to carboplatin.Methods: 1)To detect differentially expressed genes between knockdown CORO2 A expression and control in triple-negative breast cancer cell lines using transcriptomic sequencing and to analyze the differential genes for KEGG enrichment and GO enrichment;2)To validate the sequencing analysis results and the regulatory relationship between FANCD2 and p65 by RT-PCR and Western-Blot;3)To use TCGA and breast cancer patient tissue samples to explore the correlation between COR2 A expression and FANCD2 expression;4)to explore the effect of COR2A/NF-κB/FANCD2 pathway on DNA damage repair using immunofluorescence and Western-Blot assays;5)to detect the effect of inhibiting COR2A/NF-κB/FANCD2 pathway on DNA damage response by flow cytometry and Edu assay pathway on DNA damage response.6)Using the si RNA transfection method to interfere with COR2 A expression after carboplatin dosing treatment,MTS experiments were performed to explore the effect of COR2 A on carboplatin drug sensitivity,and WesternBlot experiments were used to elucidate the mechanism.Result: In triple-negative breast cancer cells,knockdown of COR2 A inhibited FANCD2 expression;in breast cancer tissues,COR2 A showed a strong positive correlation with FANCD2 expression;knockdown of p65 downregulated FANCD2 expression;inhibition of COR2 A and FANCD2 expression caused accumulation of DNA damage but did not cause a more pronounced DNA damage response at 72 H The drug sensitivity of carboplatin in triple-negative breast cancer cells was time-and dosedependent;inhibition of CORO2 A expression enhanced carboplatin sensitivity in triple-negative breast cancer;knockdown of CORO2 A combined with carboplatin administration increased DNA duplex damage in triple-negative breast cancer cells.Conclusions: In TNBC cells,CORO2 A affects NF-κB complex p65 protein content,which affects FANCD2 transcription,leading to alterations in the cellular DNA damage repair capacity.Inhibition of the CORO2A/NF-κB/FANCD2 pathway can inhibit cellular DNA damage repair function,leading to the accumulation of DNA damage.Knockdown of CORO2 A enhances the drug sensitivity of TNBC cells to carboplatin.