在乳腺癌（BC）中，缺氧与不良预后有关。Salvador同源蛋白1（SAV1）作为肿瘤抑制因子，在癌细胞中被下调。然而，关于SAV1表达谱和其在BC中的重要性的数据有限。尚未研究这种现象在缺氧微环境下的评估。本研究旨在调查在正氧和缺氧条件下的SAV1表达谱，以及SAV1在BC预后中的潜力。基因和蛋白表达分析分别使用实时定量PCR（RT-qPCR）和免疫细胞化学（ICC）进行，而体外分析则使用癌症基因组图谱（TCGA）。生存曲线使用KMplotter构建。BC样本和肿瘤细胞系中的SAV1表达水平低于正常样本。在缺氧的雌激素受体阳性（ER +）肿瘤中，SAV1 mRNA水平降低，与正氧的ER +肿瘤相比，与较低的生存概率相关。此外，进展期癌症样本中的SAV1水平较低，这与更糟糕的生存曲线相关，并可能是BC的危险因素。这些数据表明，SAV1在BC中具有潜在的预后作用，表达水平较低与更糟的预后相关。版权所有©2023年墨西哥社会保障研究所（IMSS）。Elsevier Inc.版权所有。

In breast cancer (BC), hypoxia is associated with poor prognosis. Protein Salvador homolog 1 (SAV1) acts as a tumor suppressor and is downregulated in the cancer cells. However, there is limited data on the expression profile of SAV1 and its importance in BC. It has not been studied to evaluate this phenomenon in a hypoxic microenvironment yet.This study aimed to investigate SAV1 expression profiles under normoxia and hypoxia, and the potential of SAV1 in BC prognosis.Gene and protein expression analyses were performed using Real-Time quantitative PCR (RT-qPCR) and immunocytochemistry (ICC), respectively, and in silico analyses were performed using The Cancer Genome Atlas (TCGA). The survival curves were constructed using KMplotter.SAV1 expression was lower in BC samples and tumor cell lines than in normal samples. The SAV1 mRNA levels were reduced in hypoxic estrogen receptor positive (ER+) tumors, which were associated with a lower survival probability as compared to normoxic ER+ tumors. Furthermore, lower levels of SAV1 were found in advanced cancer stage samples, which are associated with worse survival curves and can be a risk factor for BC.These data suggest a potential prognostic role of SAV1 in BC, with lower expressions associated with worse prognosis.Copyright © 2023 Instituto Mexicano del Seguro Social (IMSS). Published by Elsevier Inc. All rights reserved.