EP.TH.275The role of amino acid transporters SLC1A5 and SLC3A2 in primary breast cancer in older women. (28th October 2021)

• Record Type: Journal Article
• Authors: Parks, Ruth; Alfarsi, Lutfi; Green, Andrew; Cheung, Kwok-Leung
• Is Part Of: British journal of surgery. Volume 108:Supplement 7(2021)
• Publication Date: 2021-10-28
• Subjects: Surgery -- Periodicals; 617.005
• DOI: 10.1093/bjs/znab309.034
• Languages: English
• ISSNs: 0007-1323

Abstract

Abstract: Aims: Breast cancer in older women has more favourable biology, compared to younger women. Increased glutamine metabolism is a hallmark of cancer. The prognostic role of amino acid transporters involved with glutamine flux, SLC1A5 and SLC3A2, has been shown in breast cancer in younger women. This study aimed to investigate the role of SLC1A5 and SLC3A2 in breast cancer in older women as possible prognostic markers. Methods: Surgical specimens were obtained from an existing series of 1, 758 older women (≥70 years) with primary breast cancer, treated in a single institution with long-term (37+ years) follow-up. Of this cohort, 813 had primary surgical treatment. As part of previous work, it was possible to construct good quality tissue microarrays (TMAs) in 575 cases. Immunohistochemical staining for SLC1A5 and SLC3A2 was performed. H-score was considered as a continuous variable as well as using positivity cut-offs of ≥ 45 for SLC1A5 and ≥15 for SLC3A2, using X-tile software. Association between H-score and tumour size, grade, ER status, local-recurrence-free-survival (LRFS), overall survival (OS) and breast-cancer-specific-survival (BCSS) was investigated. Results: No correlation was seen between neither marker and LRFS, OS, or BCSS in older women with breast cancer. Both markers were associated with high tumour grade and negative ER status (both p < 0.001). Conclusions: These findings are contrary to those found in younger women, where these amino acid transporters are associated with shorter BCSS. This may suggest that breast cancer in older women is less reliant on glutamine metabolism, which is consistent with an overall less aggressive phenotype.