m6A Modification Patterns With Distinct Immunity, Metabolism, and Stemness Characteristics in Soft Tissue Sarcoma

Area of Science:

• Oncology
• Molecular Biology
• Epigenetics

Background:

• N6-methyladenosine (m6A) RNA methylation is a crucial epigenetic modification with known prognostic value in various cancers.
• The specific roles of m6A modification in immunity, metabolism, and stemness within soft tissue sarcoma (STS) remain largely unexplored.

Purpose of the Study:

• To comprehensively analyze m6A modification patterns in STS and their association with immune, metabolic, and stemness characteristics.
• To develop and validate an m6Ascore for quantifying m6A modification patterns and predicting clinical outcomes in STS patients.

Main Methods:

• Utilized machine learning algorithms to construct an m6Ascore based on data from 568 STS samples and 21 m6A regulators.
• Identified distinct m6A modification patterns and analyzed their correlations with prognosis, immune cell infiltration, metabolic pathways, stemness, somatic mutations, and copy number variations.
• Validated immunotherapy sensitivity using the IMvigor210 dataset and explored chemotherapy sensitivity.

Main Results:

• Identified two distinct m6A modification patterns in STS with significant differences in prognosis, immune infiltration, metabolism, stemness, and genomic alterations.
• Lower m6Ascores were associated with enhanced antitumor immunity, improved survival under immunotherapy, higher tumor mutation burden, increased immunogenicity, and better response to anti-PD-1/L1 therapy.
• Patients with lower m6Ascores showed potential sensitivity to docetaxel and gemcitabine, and pan-cancer analysis confirmed broad correlations of m6Ascore with clinical outcomes and biological characteristics.

Conclusions:

• m6A RNA methylation significantly influences immunity, metabolism, and stemness in soft tissue sarcoma.
• The developed m6Ascore serves as a valuable tool for evaluating m6A modification patterns, potentially guiding more effective immunotherapy and chemotherapy strategies in STS.