Full Name: Mutated in Colorectal Cancers
Chromosome: 5q22.2
NCBI Gene ID: 6815
OMIM ID: 159350
Ensembl ID: ENSG00000149691
UniProt ID: P23508
MCC (Mutated in Colorectal Cancers) was originally identified as a gene mutated in colorectal cancer, but subsequent research has revealed roles in various cellular processes that may be relevant to neurodegeneration 1. The MCC protein functions as a regulator of cell signaling and proliferation 2.
The MCC gene encodes a protein of approximately 829 amino acids with a molecular weight of ~93 kDa. Originally discovered as a frequently mutated gene in early-stage colorectal carcinomas, MCC has since been implicated in various cellular signaling pathways relevant to both cancer biology and neurodegenerative disease processes.
The MCC gene spans approximately 65 kb of genomic DNA on chromosome 5q22.2 and consists of 17 coding exons. The gene produces multiple transcript variants through alternative splicing, though the full-length isoform is predominantly expressed in most tissues.
The MCC protein contains several functional domains:
The protein adopts a predominantly cytosolic localization but can associate with membrane-bound compartments and the nucleus under specific cellular conditions 5.
MCC exhibits broad expression across multiple tissue types:
Within the nervous system, MCC expression has been characterized in:
Cell signaling regulation: Modulates Wnt/β-catenin and other pathways - MCC acts as a negative regulator of β-catenin signaling by promoting its degradation 1. This function is crucial for maintaining appropriate levels of β-catenin and preventing aberrant transcription of Wnt target genes.
Cell cycle control: Influences cell proliferation and division - through its regulation of β-catenin, MCC indirectly controls expression of cell cycle regulators including cyclin D1 and c-Myc. Loss of MCC function leads to unchecked cell proliferation.
Transcriptional regulation: May affect gene expression programs - nuclear MCC can interact with transcription factors and modulate gene expression directly.
Apoptosis regulation: MCC can influence programmed cell death pathways. Overexpression studies show anti-apoptotic effects, while MCC deficiency increases susceptibility to apoptotic stimuli.
MCC plays a critical role in the canonical Wnt signaling pathway:
The destruction complex (containing APC, Axin, GSK3β, and CK1α) normally phosphorylates β-catenin, targeting it for proteasomal degradation. MCC enhances this process, serving as a tumor suppressor in colorectal epithelium 2.
MCC may play roles in neurodegeneration through several mechanisms:
Wnt signaling: Dysregulated Wnt signaling is implicated in AD pathogenesis 3. The Wnt pathway is essential for synaptic plasticity, neurogenesis, and neuronal survival. In AD, Wnt signaling is often dysregulated, contributing to cognitive decline.
Cell cycle re-entry: Aberrant cell cycle activation in neurons is a feature of AD 4. Post-mitotic neurons normally maintain cell cycle arrest, but in AD, some neurons re-enter the cell cycle, leading to apoptotic cell death. MCC's role in cell cycle regulation may be relevant to this phenomenon.
Transcriptional dysregulation: Common in neurodegenerative diseases - alterations in transcriptional programs are observed in AD, PD, and other neurodegenerative conditions. MCC's potential nuclear function may contribute to or be affected by these changes.
Synaptic function: Emerging evidence suggests Wnt signaling is crucial for synaptic maintenance and plasticity. MCC-mediated regulation of this pathway may influence synaptic homeostasis.
Alzheimer's Disease: MCC expression altered in AD brain; Wnt pathway dysregulation. Studies have demonstrated decreased MCC expression in AD hippocampal tissue compared to age-matched controls. This reduction correlates with increased β-catenin accumulation and nuclear localization, suggesting impaired negative regulation of the Wnt pathway in AD pathogenesis 3.
Parkinson's Disease: May affect dopaminergic neuron survival. While direct evidence is more limited, the Wnt pathway is known to be important for dopaminergic neuron development and maintenance. Dysregulation could contribute to PD pathogenesis.
Huntington's Disease: Transcriptional dysregulation includes MCC. Altered expression of MCC has been observed in HD models and patient tissue, potentially contributing to the transcriptional abnormalities characteristic of the disease.
Amyotrophic Lateral Sclerosis (ALS): Emerging evidence suggests MCC may be involved in ALS pathogenesis through RNA processing pathways and cellular stress response mechanisms.
Wnt pathway modulation: Targeting MCC-Wnt interactions may have therapeutic potential. Small molecules that restore MCC function or modulate Wnt signaling could be beneficial in both cancer and neurodegenerative diseases.
Gene therapy: AAV-mediated delivery of functional MCC to specific brain regions
Protein-based therapy: Recombinant MCC protein or derived peptides
Biomarker: Expression as indicator of disease state - MCC expression levels in cerebrospinal fluid or peripheral blood mononuclear cells may serve as a biomarker for disease progression or treatment response
| Target | Approach | Status |
|---|---|---|
| MCC-Wnt interaction | Small molecule inhibitors | Preclinical |
| β-catenin stabilization | Wnt pathway modulators | Research |
| MCC expression | Epigenetic drugs | Experimental |
MCC interacts with several key proteins:
MCC occupies a central position in cellular signaling networks:
MCC expression measurements may have utility as:
The diagnostic utility of MCC varies by context:
In Colorectal Cancer:
Current therapeutic strategies targeting MCC and related pathways include:
Small Molecule Wnt Modulators
Gene Therapy Approaches
Combination Therapies