Mitochondria-nuclear crosstalk in triple negative breast cancer racial disparity

描述（由申请人提供）：对于三阴性BCa（TN BCa），目前缺乏对驱动途径的了解，因此通常使用更通用的疗法进行治疗。目前还没有临床上可接受的治疗TN BCa的目标，并预测其转移的潜力。虽然高加索人（CA）妇女中BCa的发病率较高，但非洲裔美国人（AA）妇女中BCa导致的死亡率较高。重要的是，AA患者更有可能被诊断为三阴性（TN）BCa，并且比CA处于更晚期的阶段。线粒体被认为是细胞的能量屋，与肿瘤的发生和发展密切相关，因此是化疗的潜在靶点。随着跨线粒体胞质杂交体（cybrid）技术的出现，现在可以在确定的核背景下检查肿瘤相关线粒体对肿瘤生长和发育的具体贡献。胞质杂交体是通过将含有感兴趣的线粒体的去核细胞与？0个受体细胞（携带消融的线粒体DNA的细胞）。在体外和体内环境中使用该技术，我们已经证明了TN BCa的线粒体逆行调节（MRR）进展的关键作用。我们还确定了癌症线粒体对Src致癌通路的翻译后修饰的关键调节。我们使用来自AA和CA TN BCa细胞系的具有线粒体的胞质杂交体的初步分析表明，核基因的线粒体逆行调节（MRR）在AA和CA细胞中是不同的。在这里，我们建议将联合收割机Kaipparettu博士（PI）在BCa和cybrid技术方面的专业知识与刘易斯博士在生成患者来源异种移植物方面的专业知识以及Creighton博士在生物信息学方面的专业知识相结合，以评估一个具有临床挑战性的问题，“我们如何通过MRR更好地区分AA和CA TN BCa？“从战略上讲，我们将使用从AA和CA TN BCa患者来源的异种移植物中产生的cybrid系统来分析转移性BCa中的线粒体特异性改变。? Kaipparettu实验室已经可以获得来自不同TN乳房来源的AA和CA核背景的0个细胞。将通过下一代测序确认由此产生的胞质杂交体的线粒体功能、核起源，并使用体外和体内肿瘤形成/侵袭测定评价表型变化。在此之后，将对具有AA和CA线粒体的胞质杂交体的Src途径修饰进行分析。为了识别新的途径，将通过微阵列分析胞质杂交体的MRR，并与生物统计学家Creighton博士一起使用已建立的生物统计学和生物信息学管道（Oncomine Concept Mapping）检查基因表达，以生成与AA和CA TN BCa转移相关的致癌特征和途径。将使用细胞系和异种移植模型评价指定途径在TN BCa进展中的作用。总的来说，我们期望开发出首个AA和CA TN BCa进展的由DNA驱动的致癌特征。在临床上，我们希望这些被翻译为确定AA TN BCa的新药物靶点。

DESCRIPTION (provided by applicant): For Triple Negative BCa (TN BCa), there is a current lack of understanding of driver pathways and hence are often treated using more generic therapies. Currently there are no clinically accepted targets for the treatment for TN BCa and to predict its potential to metastasize. while BCa incidence is higher in Caucasian (CA) women, death due to BCa is higher in African American (AA) women. Importantly, AA patients are more likely to be diagnosed with triple negative (TN) BCa and at a more advanced stage than CA. Mitochondria is considered the energy house of the cell and has been strongly implicated in tumor development and progression and thus serving as a potential target for chemotherapy. With the advent of Transmitochondrial cybrid (cybrid) technology, it is now possible to examine the specific contribution of tumor-associated mitochondria to neoplastic growth and development under a defined nuclear background. Cybrids are constructed by fusing enucleated cells harboring mitochondria of interest with ?0 recipient cells (cells harboring ablated mitochondrial DNA). Using this technology in both an in vitro and in vivo setting, we have demonstrated a key role for mitochondrial retrograde regulation (MRR) progression of TN BCa. We have also identified critical regulation of post-translational modification of Src oncogenic pathway by cancer mitochondria. Our preliminary analysis using cybrids with mitochondria from AA and CA TN BCa cell lines suggest that mitochondrial retrograde regulation (MRR) of nuclear genes are different in AA and CA cells. Here we propose to combine Dr. Kaipparettu's (PI) expertise in BCa and cybrid technology with Dr. Lewis expertize in generating patient derived xenografts and Dr. Creighton's expertise in bioinformatics to evaluate a clinically challenging question, "How can we better distinguish AA and CA TN BCa by its MRR?" Strategically, we will use cybrid system generated from AA and CA TN BCa patients-derived xenografts to analyze the mitochondria specific alterations in metastatic BCa. ?0 cells from different TN breast-derived AA and CA nuclear background are already available in Kaipparettu lab. The cybrids thus generated will be confirmed for their mitochondrial function, nuclear origin by next-gen sequencing and evaluated for phenotypic changes using in vitro and in vivo tumor forming/invasion assays. Following this, cybrids with AA and CA mitochondria will be profiled for their Src pathway modification. To identify novel pathways, the MRR of cybrids will be analyzed by microarray and the gene expression will be examined using an established biostatistics and bioinformatics pipelines (Oncomine Concept Mapping) together with the biostatistician Dr. Creighton to generate oncogenic signatures and pathways associated with AA and CA TN BCa metastasis. The nominated pathways will be evaluated for their role in TN BCa progression using cell line and xenograft models. Overall, we expect to develop the first- of-its-kind mitochondria-driven oncogenic signature for AA and CA TN BCa progression. Clinically, we expect these to be translated to identify new drug targets for AA TN BCa.