Department of Breast Cancer Center, Hubei Cancer Hospital, Tongji Medical College, Huazhong University of Science and Technology, National Key Clinical Specialty, Hubei Provincial Clinical Research Center for Breast Cancer, Wuhan Clinical Research Center for Breast Cancer, No.116 Zhuo Daoquan South Road, Wuhan, 430079, Hubei, China.
Department of Pathology, Tongji Medical College, Hubei Cancer Hospital, Huazhong University of Science and Technology, Wuhan, China.
Sci Rep. 2024 Oct 29;14(1):26035. doi: 10.1038/s41598-024-75922-z.
Breast cancer is the most common malignant tumor in women, and triple-negative breast cancer (TNBC) is a specific subtype of breast cancer characterized by high invasiveness, high metastatic potential, ease of recurrence, and poor prognosis. Src-like adaptor protein 2 (SLAP2), which can be involved in the regulation of multiple signaling pathways, may be a key target for TNBC. The aim of this study was to investigate the effect of overexpression of SLAP2 on TNBC and to explore the underlying mechanisms. First, we constructed and transfected SLAP2 overexpressing lentivirus based on MDA-MB-231 human TNBC cell line, screened for differential downstream target genes in combination with mRNA high-throughput sequencing (RNA-Seq), and predicted their functions and enriched pathways in conjunction with bioinformatics analysis. The effects of SLAP2 overexpression on macrophage polarization, as well as on tumor proliferation and apoptosis, were assessed by tail vein injection of a stable transfection line of 4T1 cells transfected with SLAP2 overexpressing lentivirus. The effect of SLAP2 on macrophage polarization was assessed by inducing M1/M2 polarization and transfecting SLAP2 overexpressing lentivirus. Meanwhile, a transwell co-culture system was constructed between differently treated macrophages and 4T1 cells to assess the effect of SLAP2 overexpression on the malignant behavior of the cells via macrophage polarization. Overexpression of SLAP2 revealed 179 genes up-regulated and 74 genes down-regulated by mRNA high-throughput sequencing, and the enriched functions and pathways of differential genes were mainly related to immunity response. In vivo experiments revealed that overexpression of SLAP2 inhibited the growth of tumor in nude mice, decreased the expression of ki67 in tumor tissues, and increased the rate of apoptosis in tumor tissues. Meanwhile, we found that overexpression of SLAP2 promoted macrophage polarization toward M1 type and inhibited M2 type polarization in tumors. In vitro experiments further verified its effect on M1/M2 polarization by transfecting SLAP2 overexpressing lentivirus. By transwell co-culture system, we further demonstrated that overexpression of SLAP2 inhibits cell proliferation and invasion, promotes apoptosis, up-regulates the expression of Bax in cells, and down-regulates the expression of Bcl-2 in cells by promoting macrophage M1-type polarization. Overexpression of SLAP2 inhibits TNBC progression by promoting macrophage M1-type polarization.
乳腺癌是女性最常见的恶性肿瘤，三阴性乳腺癌（TNBC）是一种特定的乳腺癌亚型，其特点是侵袭性高、转移潜能高、易复发、预后差。Src 样衔接蛋白 2（SLAP2）可参与多条信号通路的调节，可能是 TNBC 的关键靶点。本研究旨在探讨 SLAP2 过表达对 TNBC 的影响，并探讨其潜在机制。首先，我们基于 MDA-MB-231 人 TNBC 细胞系构建并转染 SLAP2 过表达慢病毒，结合 mRNA 高通量测序（RNA-Seq）筛选差异下游靶基因，并结合生物信息学分析预测其功能和富集通路。通过尾静脉注射转染 SLAP2 过表达慢病毒的 4T1 细胞稳定转染系，评估 SLAP2 过表达对巨噬细胞极化以及肿瘤增殖和凋亡的影响。通过诱导 M1/M2 极化并转染 SLAP2 过表达慢病毒来评估 SLAP2 对巨噬细胞极化的影响。同时，构建不同处理的巨噬细胞与 4T1 细胞的共培养 Transwell 体系，通过巨噬细胞极化评估 SLAP2 过表达对细胞恶性行为的影响。mRNA 高通量测序显示 SLAP2 过表达后有 179 个基因上调，74 个基因下调，差异基因的富集功能和通路主要与免疫反应相关。体内实验显示，SLAP2 过表达抑制裸鼠肿瘤生长，降低肿瘤组织中 ki67 的表达，增加肿瘤组织中细胞凋亡率。同时，我们发现 SLAP2 过表达促进肿瘤中巨噬细胞向 M1 型极化，抑制 M2 型极化。体外实验通过转染 SLAP2 过表达慢病毒进一步验证了其对 M1/M2 极化的影响。通过 Transwell 共培养体系，我们进一步证明 SLAP2 过表达通过促进巨噬细胞 M1 型极化抑制细胞增殖和侵袭，促进细胞凋亡，上调细胞中 Bax 的表达，下调细胞中 Bcl-2 的表达。SLAP2 过表达通过促进巨噬细胞 M1 型极化抑制 TNBC 进展。
