MRTFB suppresses colorectal cancer development through regulating SPDL1 and MCAM

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• Myocardin-related transcription factor B (MRTFB) is implicated as a potential tumor suppressor in various cancers.
• Colorectal cancer (CRC) remains a significant health concern with ongoing research into novel therapeutic targets.
• Understanding the molecular mechanisms underlying tumor suppression is crucial for developing effective cancer treatments.

Purpose of the Study:

• To investigate the role of MRTFB as a tumor suppressor in colorectal cancer.
• To identify downstream target genes of MRTFB involved in CRC progression.
• To validate the function of identified target genes in CRC cell invasion, migration, and tumor development.

Main Methods:

• Cell-based assays, including invasion and migration assays.
• In vivo tumor xenograft assays in mice.
• Whole transcriptome RNA sequencing for gene expression analysis.
• MRTFB and target gene (MCAM, SPDL1) knockdown studies.
• Analysis of patient data for gene expression and survival correlation.

Main Results:

• MRTFB acts as a tumor suppressor in human and mouse colorectal cancer, inhibiting cell invasion and migration.
• RNA sequencing identified MCAM and SPDL1 as potential MRTFB tumor-suppressor targets.
• Knockdown of MCAM or SPDL1 in CRC cells significantly increased invasion and migration.
• Spdl1 expression was downregulated in Mrtfb knockout mice, and lower SPDL1 correlated with reduced CRC patient survival.
• Depletion of MCAM and SPDL1 enhanced tumor development in xenograft models.

Conclusions:

• MRTFB is a validated tumor suppressor in colorectal cancer.
• MCAM and SPDL1 are key downstream effectors of MRTFB's tumor-suppressive functions in CRC.
• These findings identify novel therapeutic targets and pathways for colorectal cancer treatment and management.