Diagnostic interpretation of CFH expression in pan-cancer analyses: the importance of factor H-like 1 isoform resolution.

Recent pan-cancer analyses have identified Complement Factor H (CFH) expression as an immune-related and prognostic biomarker. However, interpretation of CFH transcriptional data requires consideration of isoform specificity. The CFH gene encodes both full-length factor H (FH) and the biologically active splice isoform factor H-like 1 (FHL-1), which differ in structure and tissue localization. Common transcriptional and knockdown approaches do not distinguish between these isoforms, potentially introducing biological heterogeneity into diagnostic and prognostic assessments. Isoform-resolved analyses may therefore enhance the specificity and clinical utility of CFH-based biomarkers in oncology.