Pathogenesis of cancers derived from thyroid follicular cells

Area of Science:

• Endocrinology
• Oncology
• Genomics

Background:

• Differentiated thyroid cancers from follicular cells possess genomic simplicity, offering insights into oncogenic driver effects on tumor phenotype.
• Key oncoproteins in thyroid cancer converge on the receptor tyrosine kinase-RAS-BRAF pathway, leading to constitutive MAPK signaling.
• The extent of MAPK pathway activation influences thyroid cancer biology, including differentiation, invasiveness, and tumor microenvironment composition.

Purpose of the Study:

• To review the genomic landscape of differentiated thyroid cancers.
• To connect genomic alterations to the resulting biological states and tumor progression.
• To elucidate the role of the tumor microenvironment in disease progression.

Main Methods:

• Review of genomic trajectories in differentiated thyroid cancers.
• Analysis of oncogenic pathway activation, particularly MAPK signaling.
• Correlation of genomic lesions with tumor phenotype and microenvironment characteristics.

Main Results:

• Oncogenic drivers primarily activate the MAPK signaling pathway.
• The magnitude of MAPK signaling flux dictates tumor differentiation, invasiveness, and microenvironment.
• Genomic lesions driving immortalization, chromatin disruption, and cell cycle dysfunction contribute to disease progression.
• Progressive immunosuppression characterizes the tumor microenvironment in advanced disease.

Conclusions:

• Genomic simplicity in differentiated thyroid cancers provides a model for understanding oncogenic driver impact.
• MAPK signaling pathway flux is a critical determinant of thyroid cancer biology.
• Tumor progression involves a combination of genomic alterations and an immunosuppressive microenvironment.