Amplifikasi CCNE1, Ekspresi mRNA CCNE1, dan Instabilitas Genom pada Karsinoma Serosa Ovarium: Analisis Terintegrasi TCGA PanCancer Atlas

CCNE1 amplification is a recurrent copy-number alteration in serous ovarian carcinoma and is thought to be associated with transcriptional activation and chromosomal instability. This study aimed to analyze the frequency of CCNE1 amplification, its association with mRNA expression, and differences in genomic instability characteristics according to amplification status. This retrospective analytical observational study used data from 201 primary tumors in the TCGA PanCancer Atlas accessed through cBioPortal. Amplification was defined as GISTIC +2. mRNA expression was analyzed as a continuous z-score, while a z-score >= 2 was used for exploratory categorical analysis. Tumor break load, aneuploidy score, fraction genome altered, mutation count, and nonsynonymous TMB were compared according to amplification status. CCNE1 amplification was identified in 43 of 201 tumors (21.4%). mRNA expression increased in accordance with the GISTIC category (Kruskal-Wallis, p < 0.001; Spearman rho = 0.607), and the amplified group showed higher expression z-scores than the non-amplified group (median 1.99 vs. 0.05; p < 0.001; rank-biserial correlation = 0.616). Amplification was also associated with high expression (OR = 7.92; 95% CI 3.62-17.30), although individual-level concordance was not perfect. Tumors with CCNE1 amplification had higher tumor break load and aneuploidy scores (both p < 0.001; q < 0.003), whereas fraction genome altered, mutation count, and TMB did not differ significantly. These findings indicate that CCNE1 amplification defines a subset of serous ovarian carcinomas characterized by increased mRNA expression and features of chromosomal instability. Integrating copy-number alteration and gene expression data may provide more informative molecular stratification than using either marker alone.