Dopamine and cyclic adenosine monophosphate-regulated phosphoprotein with an apparent Mr of 32000 promotes colorectal cancer growth

BACKGROUND Dopamine and cyclic adenosine monophosphate(cAMP)-regulated phosphop-rotein with an apparent Mr of 32000(DARPP-32)is a protein that is involved in regulating dopamine and cAMP signaling pathways in the brain.However,recent studies have shown that DARPP-32 is also expressed in other tissues,including colorectal cancer(CRC),where its function is not well understood.AIM To explore the effect of DARPP-32 on CRC progression.METHODS The expression levels of DARPP-32 were assessed in CRC tissues using both quantitative polymerase chain reaction and immunohistochemistry assays.The proliferative capacity of CRC cell lines was evaluated with Cell Counting Kit-8 and 5-ethynyl-2’-deoxyuridine assays,while apoptosis was measured by flow cytometry.The migratory and invasive potential of CRC cell lines were deter-mined using wound healing and transwell chamber assays.In vivo studies involved monitoring the growth rate of xenograft tumors.Finally,the underlying molecular mechanism of DARPP-32 was investigated through RNA-sequencing and western blot analyses.RESULTS DARPP-32 was frequently upregulated in CRC and associated with abnormal clinicopathological features in CRC.Overexpression of DARPP-32 was shown to promote cancer cell proliferation,migration,and invasion and reduce apoptosis.DARPP-32 knockdown resulted in the opposite functional effects.Mechanistically,DARPP-32 may regulate the phosphoinositide 3-kinase(PI3K)/AKT signaling pathway in order to carry out its biological function.CONCLUSION DARPP-32 promotes CRC progression via the PI3K/AKT signaling pathway.