MULTIPLEXED ISOFORM QUANTIFICATION IN HER2-POSITIVE BREAST CANCER

HER2 阳性乳腺癌的多重异构体定量

基本信息

批准号：
10362550
负责人：
Amy Elizabeth Herr
金额：
$ 34.53万
依托单位：
UNIVERSITY OF CALIFORNIA BERKELEY
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-03-03 至 2025-02-28
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10362550
关键词：
Address Automobile Driving Binding Biological Biological Assay Biological Markers Biology Biomedical Engineering Biometry Biopsy Breast Cancer Cell Breast Cancer Patient Breast Cancer Treatment Breast Cancer cell line Breast biopsy Cells Chemistry Classification Clinical Computational Biology DNA DNA Sequence Alteration Detection Development Diagnosis Dimerization Drug Targeting Drug resistance ERBB2 gene ERBB3 gene Exhibits Extracellular Domain Fluorescence Resonance Energy Transfer Fluorescent in Situ Hybridization Genomics Goals Heterogeneity Homo In Situ Hybridization Individual Knowledge Length Life Malignant Neoplasms Mammary Gland Parenchyma Maps Measurement Measures Medicine Membrane Microfluidics Molecular Monitor Mutation Nature Nuclear Oncogenic PIK3CA gene Patients Pertuzumab Pharmaceutical Preparations Play Population Analysis Precision therapeutics Prognostic Marker Protein Family Protein Isoforms Proteins Proteomics Radiation therapy Recurrence Research Resistance Resolution Retinal blind spot Role Signal Transduction Specificity Surface Survival Rate Tissue Banks Tissue Sample Tissues Trastuzumab Variant Western Blotting base biological heterogeneity cancer cell cancer drug resistance clinically relevant design dimer experience fundamental research improved individualized medicine malignant breast neoplasm multimodality mutant neoplastic cell news next generation novel therapeutics oncology program overexpression patient oriented precision medicine protein complex single cell analysis stem success targeted cancer therapy targeted treatment therapy resistant tool tumor heterogeneity

项目摘要

While targeted therapy increases overall survival rates in HER2-positive breast cancer patients, most patients will experience recurrence due to resistance to initially successful therapy (trastuzumab-based). Accordingly, there is an unmet, patient-driven need to understand and circumvent breast cancer resistance, to even targeted therapies. At the cellular level, cell-to-cell variation (heterogeneity) is a hallmark of cancer. Perhaps surprisingly, molecular heterogeneity is also a hallmark of HER2+ breast cancer. Spanning the outer membrane of a cancer cell, the large protein HER2 displays an extracellular domain, which is the target of ‘targeted therapies’ (vs. chemo- or radiation therapies). These HER2+ breast cancer targeted therapies include the landmark drug Herceptin® (trastuzumab). But the HER2 protein manifests as a family of proteins (called protein isoforms), not just a single molecular form. Regrettably, numerous of these HER2 isoforms lack the extracellular domain of the full-length HER2 protein, making the cell non-responsive otherwise powerful anti- HER2 targeted therapies. These smaller HER2 isoforms are known as ‘truncated isoforms’, with a 95 kDa form ‘P95HER2’ being especially potent in drug resistance. Until our previous R01 research, the ability to discern full-length HER2 from the truncated P95HER2 isoform was not readily possible with same-cell resolution. Consequently, to advance our knowledge of resistance to anti-HER2 targeted therapies, we propose to build on our team’s capacity to precisely distinguish P95HER2 from other HER2 protein forms to scrutinize the role of P95HER2 in: (1) the potent, signal-activating HER2 dimers that reside on the surface of each breast cancer cell and (2) potentially ultra-resistant breast cancer cell subpopulations that exhibit both the P95HER2 protein isoform and the resistance-driving DNA mutation (PIK3CA). These are two cellular ‘modes’ (P95HER2 homo/heterodimers; co-expression of P95HER2 and PIK3CA mutation) that no other tools can directly and with high-specificity concurrently measure in minute tissue samples, down to single-cell resolution. Our clinical, biostatistics, and bioengineering team will conduct research to yield tools that can perform these isoform- involved multimodal assays in tissues and cells from HER2-positive breast cancer patient biopsies (Stanford Breast Tissue Bank), after performing early development on well-characterized breast cancer cell lines. The ability to directly measure the truncated HER2 isoforms and interaction modes in sparingly available breast biopsy tissues and with single-cell resolution should yield a tremendous advantage for understanding and then assessing the potential for drug resistance. These studies will allow us to profile the cellular and molecular heterogeneity of HER2 to advance understanding of persistent breast cancer resistance to anti-HER2 targeted treatment and, ultimately, to identify approaches to reduce or eliminate recurrence.

靶向治疗增加了HER2阳性乳腺癌患者的总生存率，但大多数患者由于对最初成功的治疗（基于曲妥珠单抗）的抵抗，将经历复发。有一个未满足的，患者驱动的需要了解和避免乳腺癌的抗性，甚至靶向疗法。在细胞水平上，细胞间变异（异质性）是癌症的标志。也许令人惊讶的是，分子异质性也是HER2+乳腺癌的标志。跨越外部癌细胞的膜，大蛋白HER2显示一个细胞外域，这是 “靶向疗法”（相对于化学疗法或放射疗法）。这些HER2+乳腺癌针对的疗法包括具有里程碑意义的毒品Herceptin®（Trastuzumab）。但是HER2蛋白表现为一种蛋白质家族（计算）蛋白质同工型），不仅是单个分子形式。遗憾的是，其中许多HER2同工型缺乏全长HER2蛋白的细胞外结构域，使细胞无反应性强大的抗 - HER2靶向疗法。这些较小的HER2同工型被称为“截短的同工型”，形式为95 kDa “ p95her2”在耐药性方面特别有潜力。直到我们以前的R01研究才能辨别通过相同细胞分辨率，不容易实现来自截短的P95HER2同工型的全长HER2。因此，为了促进我们对抗HER2靶向疗法的抵抗的了解，我们建议建立根据我们团队的能力，可以将P95HER2与其他HER2蛋白质形式区分开来审查角色 p95her2 in：（1）驻留在每个乳腺癌表面的电势，信号激活的HER2二聚体细胞和（2）潜在的超耐乳腺癌细胞亚群，均暴露了P95Her2蛋白同工型和阻力驱动DNA突变（PIK3CA）。这是两个细胞“模式”（p95her2 同性恋/异二聚体； p95her2和pik3ca突变的共表达），没有其他工具可以直接而使用高特异性在微小组织样品中同时进行测量，直至单细胞分辨率。我们的临床生物统计学和生物工程团队将进行研究以产生可以执行这些同工型的工具涉及来自HER2阳性乳腺癌患者活检的组织和细胞中的多模式测定（斯坦福乳房组织库），在对良好的乳腺癌细胞系进行了早期发育后。这能够直接测量较少可用的乳房中截短的HER2同工型和相互作用模式活检组织和单细胞分辨率应具有巨大的优势，然后评估耐药性的潜力。这些研究将使我们能够介绍细胞和分子 HER2的异质性，以提高人们对抗乳腺癌抗抗HER2的抗性的理解有针对性的治疗，并最终确定减少或消除复发的方法。