Bioinformatics Analysis Reveals Microrchidia Family Genes as the Prognostic and Therapeutic Markers for Colorectal Cancer
Authors: Liu Binghui , Chen Lingbin , Chen Hui , Pan Juhua , Yu Changfa 
Published: January 2025

Aim:
The aim of this study is to examine the role of the microrchidia (MORC) family, a
group of chromatin remodeling proteins, as the therapeutic and prognostic markers for colorectal cancer
(CRC).

Background:
MORC protein family genes are a highly conserved nucleoprotein superfamily whose
members share a common domain but have distinct biological functions. Previous studies have analyzed
the roles of MORCs as epigenetic regulators and chromatin remodulators; however, the involvement of
MORCs in the development and pathogenesis of CRC was less examined.

Objective:
The current work examined the role of the MORCs as the therapeutic and prognostic markers
for CRC.

Methods:
The expressions and prognostic significance of MORC family genes in CRC were explored.
The role of these genes in tumor immunity was comprehensively analyzed in terms of their functions in
immune cell infiltration, tumor microenvironment (TME), and their interaction with immune regulatory
genes such as immunosuppressive genes, immune checkpoints and immunostimulatory genes. The relations
between MORC family genes, tumor mutation burden (TMB), DNA, mismatch repair (MMR),
RNA methylation, microsatellite instability (MSI), and drug sensitivity were investigated using the R
statistical software. The expressions of MORC4 in 150 CRC tissues and 60 paracancer tissues were detected
by immunohistochemical method. CRC cell proliferation, migration, and invasion were measured
by cell counting kit-8 (CCK-8), scratch assay, and transwell cell invasion assay.

Results:
The expressions of MORC2 and MORC4 were significantly upregulated, whereas those of
MORC1 and MORC3 were noticeably downregulated in CRC in comparison to their expressions in normal
colorectal mucosal tissues. Patients with high-expressed MORC2 showed a more unfavorable prognosis
than those with a low MORC2 level. Functional annotation analysis identified 100 MORC family
genes with the most significant negative or positive correlations to diabetic cardiomyopathy, amyotrophic
lateral sclerosis, oxidative phosphorylation, Huntington’s disease, thermogenesis, Parkinson’s disease,
olfactory transduction, Alzheimer’s disease, prion disease. MORC3 expression was positively correlated
with Stromal score, Immune score and ESTIMATE score, while MORC2 expression was negatively
related to the three scores in CRC, these correlations were not statistically significant. Additionally,
the MORC family genes were significantly positively correlated with tumor-infiltrating immune
cells such as T helper cells and exhibited close relations to some immunosuppressive genes such as CXCR4
and PVR, immunostimulatory genes such as TGFBR1, KDR, and CD160 as well as some immune
checkpoint genes. It was found that the expressions of some members of MORC family genes were positively
correlated with DNA methylation, MSI, TMB, MMRs, and drug sensitivity in CRC and that the
mRNA and protein levels of MORC4 were remarkably upregulated in CRC tissues than in adjacent normal
tissues (P<0.05). In the MORC4 knockdown group, DLD-1 cell proliferation was more inhibited
than in the negative control (NC) and siRNA groups (P<0.05). Furthermore, the migratory capacity of
DLD-1 cells and the number of cells crossing the basement membrane in the MORC4 knockdown
group were reduced compared to the NC and siRNA groups (all P<0.05).

Conclusion:
The expressions of MORC family genes were significantly different in CRC samples,
which was related to the immune cell infiltration and prognosis of CRC. Thus, the MORC family genes
were considered as markers for indicating the clinical immunotherapy and prognostic outcome of CRC.