The molecular mechanism of nuclear signaling for degradation of cytoplasmic DNA: Importance in DNA damage response and cancer

•SIRT1 improves DNA repair through fixing double-strand DNA breaks and helping nucleotide excision repair.•DNA damage induces autophagy by the hel of many mechanisms and proteins including JNK phosphatase MKP-1, PARP1, and AMPK.•The HuR function is controlled by DDR ingredients especially ATM/ATR and Chk1/Chk2.•Dif1 is regulated throughout the cell-cycle and DNA-damage, which happens through the Mec1/Dun1 pathway. This review summarizes and addresses non-coding RNAs (rRNA, tRNA, Vault and Y RNA, snRNA, and miRNA) cytoplasmic decay pathways, the molecules, enzymes, and modifications such as uridylation, which play vital roles in the degradation processes in various eukaryotic organisms. Plus, SIRT1′s role in fundamental cellular processes, including autophagy, DNA repair, DNA damage response (DDR), and the molecular mechanisms, is explored. Further, the HuR (an RNA-binding protein) impact on the expression of genes following DNA damage, and the pathways that regulate HuR function, which is through phosphorylation by Chk1/Cdk1 and Chk2, are specified. Finally, the role of DIF1/ Rnr2-Rnr4 in DDR has been discussed.