New approach based on enzyme stimulating of peptides for targeting drug resistance breast cancers

摘要 三阴性乳腺癌（TNBC）是一种不表达雌激素的乳腺癌 受体（ER）、孕酮受体（PR）和人表皮生长因子受体2（HER 2） 这种蛋白质占所有乳腺癌病例的15- 20%。TNBC肿瘤通常较大， 更高级别，并且比其他乳腺癌类型更具侵略性。TNBC不太可能回应 激素治疗药物，包括他莫昔芬和芳香酶抑制剂。TNBC也不太可能 对靶向HER 2蛋白的药物有反应，如赫赛汀（曲妥珠单抗）。治疗 TNBC患者由于缺乏分子靶标而具有挑战性。因此，有一个关键的 我们需要开发更有效的TNBC和耐药乳腺癌疗法。的 开发新的治疗方法将需要完全不同的方法， TNBC细胞特异性的反应，而不是细胞受体。 该建议假设，适当设计的Eyes Absent酶（EYA）的肽底物， 可通过自组装过程选择性抑制TNBC细胞生长。中心假设是 TNBC中EYA的酪氨酸磷酸酶活性可以特异性地将肽治疗剂转化为 纳米纤维和诱导TNBC细胞的受控凋亡。初步数据显示， 仅添加一个氨基酸的修饰肽序列可以被EYA去磷酸化 并自组装成纳米结构以抑制TNBC细胞的生长（MDA-MB-231）。在这 本课题通过改变可变因子合成EYA的不同肽底物， 结构与酶活性和细胞凋亡的相关性将通过关注 以下目标： 目的1：设计和合成EYA酶的自组装肽底物;目的2： 确定肽底物在球状体3D细胞培养物中抑制TNBC的功效。 酶动力学和靶向EYA的纳米结构的活性之间的相关性将 被评价。目的3：检测TNBC细胞的凋亡反应。本研究将 导致发现了有效的肽底物和抑制TNBC细胞的有效剂量， 凋亡细胞死亡

Abstract Triple-negative breast cancer (TNBC) is a type of breast cancer that does not express the estrogen receptors (ER), progesterone receptors (PR), and human epidermal growth factor receptor 2 (HER2) protein which accounts for 15–20 % of all breast cancer cases. TNBC tumors are generally larger, are of higher grade, and are more aggressive than other breast cancer types. TNBC is unlikely to respond to hormonal therapy medicines, including tamoxifen and aromatase inhibitors. TNBC also is unlikely to respond to medicines that target the HER2 protein, such as Herceptin (trastuzumab). Treatment of TNBC patients has been challenging due to the lack of molecular targets. Therefore, there is a critical unmet need to develop more effective therapies for TNBC and drug-resistant breast cancers. The development of new treatments would require radically different approaches that rely on enzymatic reactions specific to TNBC cells rather than the cell receptors. This proposal hypothesizes that properly designed peptide substrates of Eyes Absent enzyme (EYA) can selectively inhibit TNBC cell growth by a self-assembling process. The central hypothesis is that tyrosine phosphatase activity of EYA in TNBC could specifically convert the peptide therapeutics into nanofibers and induce controlled apoptosis of TNBC cells. The preliminary data suggested that a modified sequence of peptides with only one added amino acid could be de-phosphorylated by EYA and self-assemble into nanostructures to inhibit the growth of TNBC cells (MDA-MB-231). In this project, different peptide substrates of EYA will be synthesized by changing variable factors and the correlation of structure to enzyme activity and cell apoptosis will be determined by focusing on the following aims: Aim 1: Design and synthesize self-assembling peptide substrates for EYA enzymes; Aim 2: Determining the efficacy of peptide substrates for inhibiting TNBC in spheroid 3D cell cultures. The correlation between the enzyme kinetic and the activity of nanostructures for targeting EYA will be evaluated. Aim 3: The apoptosis response of the TNBC cells will be determined. This study will lead to finding the potent peptide substrate and the effective dose for inhibiting TNBC cells with apoptosis cell death.