catenin expression in endometrioid type endometrial cancer: Expression patterns and impact on disease outcomes

• Published in: Oncology letters 2024-12, Vol.28 (6), p.1
• Main Authors: Han, Orkun, Alci, Aysun, Yildirim, Hulya Tosun, Gokkaya, Mustafa, Yalcin, Necim, Kandemir, Selim, Goksu, Mehmet, Ureyen, Isin, Toptas, Tayfun
• Format: Article
• Language: English
• Subjects: Cancer; Endometrial cancer; Gene mutations; Genetic aspects; Health aspects; Immunohistochemistry; Methods; Patient outcomes; Transcriptional coactivators
• ISSN: 1792-1074
• DOI: 10.3892/ol.2024.14713

Determination of nuclear and/or cytoplasmic expression of [beta]-catenin by immunohistochemistry in patients with endometrial cancer (EC) may constitute a potential diagnostic method for identifying patients with a catenin [beta]1 (CTNNB1) gene mutation and those at risk of disease recurrence. The present study aimed to investigate [beta]-catenin expression patterns in hysterectomy specimens of patients with endometrioid type EC using immunohistochemistry, and to examine the prognostic impact of [beta]-catenin. The study was a single-institutional, retrospective cohort trial enrolling consecutive patients with a postoperative histopathological diagnosis of endometrioid EC who underwent hysterectomy between January 2015 and December 2018. Histopathology slides from 75 patients were stained with a monoclonal antibody targeting the [beta]-catenin protein. Any percentage of nuclear staining, whether focal or diffuse, was considered '[beta]-catenin nuclear-positive'. The cytoplasmic staining reaction of [beta]-catenin was assessed based on the percentage of stained cells and staining intensity. Immune-reactivity score (IRS) values were determined by multiplying the scores for the percentage of staining and staining intensity. IRS values 0 to 2 were regarded as negative expression, 3 to 4 as low expression, 6 to 8 as moderate expression, and 9 to 12 as high expression. Recurrence-free survival (RFS) was used as the prognostic endpoint. Only 2 out of 75 tissue samples (2.7%) exhibited nuclear [beta]-catenin expression, with a low staining percentage of 5%. By contrast, cytoplasmic staining was observed in all samples (100%). According to the IRS findings, 1.3% of the samples exhibited negative cytoplasmic expression, 42.7% low expression, 38.7% moderate expression and 17.3% high expression. Cox regression analysis revealed that staining with [beta]-catenin, either nuclear or cytoplasmic, had no impact on RFS, and stage was the sole independent prognostic factor. In conclusion, based on these results, [beta]-catenin expression in endometrioid EC was revealed to be mostly cytoplasmic, with only 2.7% of tissue samples exhibiting nuclear expression. Overall, [beta]-catenin expression has no impact on RFS. Key words: endometrioid endometrial cancer, [beta]-catenin, prognosis, survival