What is the role of CHCHD2 in adrenal tumourigenesis?

Endocrine. 2023 Aug;81(2):357-367. doi: 10.1007/s12020-023-03393-9. Epub 2023 May 23.

Abstract

Purpose: CHCHD2 is an antiapoptotic mitochondrial protein acting through the BCL2/BAX pathway in various cancers. However, data on the regulatory role of CHCHD2 in adrenal tumourigenesis are scarce.

Methods: We studied the expression of CHCHD2, BCL2, and BAX in human adrenocortical tissues and SW13 cells. mRNA and protein levels were analyzed through qPCR and immunoblotting, respectively, in 16 benign adrenocortical neoplasms (BANs), along with their adjacent normal adrenal tissues (controls), and 10 adrenocortical carcinomas (ACCs). BCL2/BAX mRNA expression was also analyzed in SW13 cells after CHCHD2 silencing. MTS, flow cytometry and scratch assays were performed to assess cell viability, apoptosis, and invasion, respectively.

Results: BCL2 and CHCHCD2 mRNA and protein expression was increased in BANs compared to normal adrenal tissues whereas BAX was decreased. BAX and CHCHD2 mRNA and protein levels were significantly downregulated and upregulated, respectively, in ACCs compared with either BANs or controls. Expression of the studied genes was not different among cortisol-secreting and nonfunctional ACAs. No significant association was found between genes' expression and other established prognostic markers of ACCs patients. In vitro analysis showed that CHCHD2 silencing resulted in reduced cell viability and invasion as well as increased SW13 cells apoptosis.

Conclusions: CHCHD2 expression seems to be implicated in adrenal tumourigenesis and its absence resulted to increased apoptosis in vitro. However, the exact mechanism of action and particularly its association with the BAX/BCL2 pathway needs to be further studied and evaluate whether it could be a protentional therapeutic target.

Keywords: Adrenal adenomas; Adrenocortical carcinoma; Apoptosis; BAX; BCL2; CHCHD2.

MeSH terms

  • Adrenal Cortex Neoplasms* / metabolism
  • Adrenocortical Carcinoma* / metabolism
  • Apoptosis / genetics
  • Carcinogenesis / genetics
  • Cell Transformation, Neoplastic
  • DNA-Binding Proteins / therapeutic use
  • Humans
  • RNA, Messenger / metabolism
  • Transcription Factors / metabolism
  • bcl-2-Associated X Protein / genetics
  • bcl-2-Associated X Protein / therapeutic use

Substances

  • bcl-2-Associated X Protein
  • RNA, Messenger
  • CHCHD2 protein, human
  • DNA-Binding Proteins
  • Transcription Factors