Metabolic buffering restricts phenotype switching in melanoma

Area of Science:

• Cancer Biology
• Metabolic Regulation
• Epigenetics

Background:

• Phenotypic heterogeneity in cancer, driven by the metabolic microenvironment, contributes to metastasis and therapy resistance.
• Nutrient limitation can induce transitions from proliferative to invasive cancer cell phenotypes.
• The capacity of cancer cells to delay these phenotype switches remains largely unknown.

Purpose of the Study:

• To investigate the role of glucose availability and glycogen metabolism in regulating cancer cell phenotypic transitions.
• To determine if cancer cells can buffer glucose to delay phenotype switching, using melanoma as a model.

Main Methods:

• Analysis of glycogen levels in proliferating versus invasive melanoma cells.
• Assessment of the impact of impaired glycogen storage and metabolism on phenotype stability.
• Correlation of glycogen levels with tissue invasion depth in primary melanomas.
• Evaluation of the association between glycogen-related enzyme expression (PYGB/L, PGM1) and patient survival.

Main Results:

• Proliferating melanoma cells exhibit high glycogen levels, while invasive cells show depleted stores.
• Impaired glycogen storage and metabolism lead to unstable phenotypes and a switch from proliferation to invasion.
• Stored glycogen levels inversely correlate with invasion depth in primary melanomas.
• Reduced expression of PYGB/L and PGM1 is linked to poorer patient survival.

Conclusions:

• Metabolic glucose buffering via glycogen accumulation and mobilization is a key determinant of invasive phenotype transitions in skin cancer.
• This metabolic control mechanism may represent a broader paradigm in other cancer types.
• Targeting glycogen metabolism could offer new therapeutic strategies for preventing melanoma metastasis.