Discerning the role of semaphorin 7a in mammary tumor growth and anti-tumor immunity

项目 早些时候 这个 年份 分娩， 这些 船只。 是 7A-一种在癌症中激活整合素-β-1信号的信号分子-在PBC和PBC中上调 与LVD、TAMS和转移的增加有关。此外，SEMA7A+肿瘤概括了 PPBC中观察到的加速肿瘤形成和转移特征与SEMA7A高表达相关 总体存活率下降。因此，PPBC可能只代表SEMA7A+癌症的一部分；有 摘要/摘要 乳腺癌的检测和治疗减少了乳腺癌相关死亡的数量，但仍 15-54岁女性癌症相关死亡的主要原因。在所有确诊的BCS中，超过一半的患者是女性。 年龄符合产后乳腺癌(PPBC)的定义，BCS在10年内确诊 与在未分娩患者中诊断的BCS相比，它们转移的可能性是2-3倍。 死亡通常归因于肿瘤细胞通过血液和淋巴传播到远处组织。 淋巴管密度(LVD)、淋巴管侵袭和淋巴结阳性(LN+)增加 常见于PPBC，预后较差。我们已经确认了信号素 (SEMA7A) T L 目前还没有针对SEMA7A的治疗方法。 至 肿瘤相关 (TME)。 预后 SEMA7A+BCS例证了癌症的四个关键特征：1)耐药 细胞死亡，2)血管生成和淋巴管生成，3)免疫逃避，4)侵袭和转移。 巨噬细胞(TAM)参与了每一个过程，并创造了一个有利于肿瘤的微环境。 由于TAMs和LVD在SEMA7A+BC中被扩增，它们很可能导致更糟糕的情况 PPBC的。SEMA7A还可以将巨噬细胞极化成TAMs的一个子集(称为“POEMS”)， 表达淋巴相关蛋白。这些诗词嵌入淋巴管，形成PEOPE-LEC 嵌合血管和肿瘤细胞在POEM-LEC连接处与这些血管相联系，可能参与肿瘤的发生。 牢房逃脱。此外，SEMA7A还能促进BC细胞、LECs、TAMs和TAMs上PD-L1的表达 抑制抗肿瘤免疫的POEMS；然而，SEMA7A对TME免疫细胞的额外作用 还没有被调查。总而言之，这让我们得出了SEMA7A激活支持生存的假设 在免疫抑制POEMS中发出信号以促进肿瘤细胞的扩散。 这项建议的目标是：1)确定SEMA7A诱导细胞存活的机制 并将免疫TME改变为亲肿瘤状态，以及2)研究POEMS产生的化学诱导剂 将肿瘤细胞招募到POEM-LEC连接并促进转移。在目标1中，我们将定义机制 SEMA7A诱导的细胞存活及对TME免疫细胞的影响。我们还将确定是否 单抗诱导对SEMA7A的抑制会阻碍肿瘤生长和免疫抑制。在目标2中， 我们将定义将肿瘤细胞招募到POEM-LEC连接的化学诱导剂。这些研究的结果将 确定SEMA7A如何促进肿瘤进展、免疫抑制和淋巴转移， 并为以SEMA7A+BCS为靶点的未来治疗提供洞察力，从而提高许多BC患者的生存率。

Project Early the years childbirth, These vessels. are 7a —a signaling molecule that activates integrin-β1 signaling in cancer—is upregulated in PPBC and is associated with increased LVD, TAMs, and metastasis. Additionally, SEMA7A+ tumors recapitulate the accelerated tumorigenesis and metastatic profiles observed in PPBC and high SEMA7A expression correlates with decreased overall survival. As such, PPBCs likely only represent a subset of SEMA7A+ cancers; there are Summary/Abstract detection and reatment of breast cancer (BC) has reduced the number of BC-related deaths but remains leading cause of cancer-related death in women ages 15-54. Over half of all BCs diagnosed i n women <40 of age fit the definition of postpartum breast cancer (PPBC), BCs diagnosed within 10 years of last which are 2-3 times more likely to metastasize compared to BCs diagnosed in nulliparous patients. deaths are generally attributed to dissemination of tumor cells to distant tissues via blood and lymphatic Increased lymphatic vessel density (LVD), ymphovascular invasion, and lymph node positivity (LN+) frequently observed in PPBC and are associated with worse prognosis. We have identified that semaphorin (SEMA7A) t l currently no therapies targeting SEMA7A. to Tumor-associated (TME). prognosis SEMA7A+ BCs exemplify four key hallmarks of cancer: 1) resistance cell death, 2) angiogenesis and lymphangiogenesis, 3) immune evasion, and 4) invasion and metastasis. macrophages (TAMs) are i mplicated in each and in creating a pro-tumor microenvironment As TAMs and LVD are amplified in SEMA7A+ BC, it is probable that they contribute to the worse of PPBC. SEMA7A can also polarize macrophages into a subset of TAMs (termed “PoEMs”) that express lymphatic-associated proteins. These PoEMs intercalate into lymphatic vessels to form PoEM-LEC chimeric vessels and tumor cells associate with these vessels at PoEM-LEC junctions, which may mediate tumor cell escape. Moreover, SEMA7A can promote expression of PD-L1-expression on BC cells, LECs, TAMs, and PoEMs to suppress anti-tumor immunity; however, additional effects of SEMA7A on immune cells of the TME have not been investigated. Altogether, this led us to the hypothesis that SEMA7A activates pro-survival signaling in immunosuppressive PoEMs to promote tumor cell dissemination. Thegoals of thisproposal are to: 1) determine the mechanisms by which SEMA7A induces cell survival and alters the immune TME to a pro-tumor state, and 2) investigate the chemoattractants produced by PoEMs that recruit tumor cells to PoEM-LEC junctions and promote metastasis. In aim 1, we will define the mechanisms of SEMA7A-induced cell survival and effects on immune cells of the TME. We will also establish whether monoclonal antibody-induced inhibition of SEMA7A impedes tumor growth and immune suppression. In aim 2, we will define chemoattractants that recruit tumor cells to PoEM-LEC junctions. The results of these studies will identify how SEMA7A promotes tumor progression, immunosuppression, and lymphatic-meditated metastasis, as well as offer insight for future therapies to target SEMA7A+ BCs, thus improving survival for many BC patients.