Circ0001320 inhibits lung cancer cell growth and invasion by regulating TNFAIP1 and TPM1 expression through sponging miR-558

AbstractLung cancer is the most affected malignant tumor in the world, and its specific pathogenesis is still unclear. It has been confirmed that circ0001320 is down-regulated in lung cancer, but its mechanism has not been reported. Further study found that circ0001320 was down-regulated in lung cancer cells, localized in the cytoplasm, and had multiple miR-558 binding sites. Dual-luciferase reporter gene assay, RNA-pull-down, and immunoprecipitation experiments all confirmed that circ0001320 directly bound to miR-558, and then inhibit the expression of miR-558. MiR-558 was up-regulated in lung cancer cells, and bound the downstream target genes TNFAIP1 and TPM1 to inhibit their expression. Western blot showed that circ0001320 significantly up-regulated the protein levels of TNFAIP1 and TPM1, while miR-558 blocked this effect of circ0001320. Circ0001320, TNFAIP1, and TPM1 all inhibited the proliferation and invasion of lung cancer cells and promoted apoptosis, while miR-558 had the opposite effects. After transfection with circ0001320 overexpression vector, miR-558 up-regulation or down-regulation of TNFAIP1, or TPM1 expression significantly reversed the inhibition of cell growth and invasion by circ0001320. Similarly, the expression of TNFAIP1 or TPM1 was down-regulated, while miR-558 expression was inhibited, and the levels of cell proliferation, apoptosis, and invasion did not change significantly. Therefore, these fully show that circ0001320 inhibits the growth and invasi...

Source: Human Cell - October 31, 2020 Category: Cytology Source Type: research