APOPTOSIS & CELL CYCLE IN BREAST & OVARIAN CANCER CELLS

细胞凋亡

• 批准号: 6032882
• 负责人: JAY wimalasena WIMALASENA
• 金额: $ 23.73万
• 依托单位: UNIVERSITY OF TENNESSEE KNOXVILLE
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-02-01 至 2003-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6032882
• 关键词: BCL2 gene /protein; MCF7 cell; apoptosis; breast neoplasms; cell cycle; cell growth regulation; cyclin dependent kinase; estradiol; estrogen inhibitor; hormone regulation /control mechanism; microtubules; neoplastic cell; ovary neoplasms; p53 gene /protein; paclitaxel; protooncogene

Previous work in our laboratory has demonstrated that the paclitaxel induced initial phase of apoptosis in a variety of cell lines including MCF-7 breast cancer cells and BR ovarian cells is mediated through a Ras/Rac/Ask1/JNKK/JNK signal transduction pathway. However, the second phase of paclitaxel action is not prevented by blockade of this pathway. Recent studies on MCF-7 cells and a variety of other cell types suggests that estrogens can inhibit apoptosis, more specifically, data indicates a possible interaction between paclitaxel and estrogens in regulating apoptosis in breast cancer cells. Several studies also suggest that antiestrogens have apoptotic effects in ER positive breast Ca cells. We have accumulated preliminary evidence confirming an anti-apoptotic role for estrogens in MCF-7 cells. However, the mechanisms of estrogen action as an anti-apoptotic agent or their potential interactions with pro-apoptotic agents such as paclitaxel are totally unknown. Elucidations of these interactions is particularly significant since estrogens and microtubule interfering agents (MIAs) such as paclitaxel have clinically established roles in promotion and therapy of breast and ovarian cancer respectively. We propose that estrogens can act as anti-apoptotic agents because of their ability to regulate the Ras/Rac-JNK pathway and the Cdk/cyclin/Cdk inhibitor activity in breast and ovarian cancer cells. We have proposed the following Specific Aims to test this broad hypothesis. Specific Aim 1: Determine the role of Cdks in the apoptotic action of paclitaxel in MCF-7 and BR and BG1 (ovarian) cancer cells with the intention of elucidating the role of the cell cycle, if any, in paclitaxel action. Specific Aim 2: Analyze the putative interactions between paclitaxel and estradiol in regulating apoptosis in the above cell lines. Experiments will be designed to elucidate interaction of estrogens with the Ras/Rac/JNKK/JNK/AP1 pathway activated by paclitaxel. Specific Aim 3: Given the fact that estrogens can regulate the activity of several genes which can modulate apoptosis, we will determine potential role of c-myc, Bc12, p53, p300/CBP Akt in the anti apoptotic effects of estradiol using overexpression of wild type and dominant negative (DN) versions of the genes of interest.

我们实验室中的先前工作表明，紫杉醇在多种细胞系中诱导的凋亡的初始阶段，包括MCF-7乳腺癌细胞和BR卵巢细胞，是通过RAS/RAC/RAC/ASK1/JNKK/JNK/JNK信号转导途径介导的。 但是，紫杉醇作用的第二阶段并不能阻止该途径的阻塞。 关于MCF-7细胞和各种其他细胞类型的最新研究表明，雌激素可以抑制细胞凋亡，更具体地，数据表明紫杉醇和雌激素在调节乳腺癌细胞中凋亡时可能存在相互作用。 几项研究还表明，抗雌激素在ER阳性乳腺CA细胞中具有凋亡作用。 我们积累了初步证据，证实了MCF-7细胞中雌激素的抗凋亡作用。 然而，雌激素作用作为抗凋亡剂的机制或其与丙酰丙酰胺等促凋亡剂（如紫杉醇）的潜在相互作用是完全未知的。这些相互作用的阐明尤其重要，因为雌激素和微管干扰剂（MIA）（例如紫杉醇）分别在促进和治疗乳腺癌和卵巢癌中具有临床上确定的作用。 我们建议雌激素可以作为抗凋亡剂，因为它们可以调节RAS/RAC-JNK途径以及CDK/Cyclin/cyclin/cdk抑制剂在乳腺癌和卵巢癌细胞中的活性。 我们提出了以下特定目的来检验这一广泛的假设。 具体目标1：确定CDK在MCF-7和BR和BG1（卵巢）癌细胞中紫杉醇在凋亡作用中的作用，目的是阐明细胞周期在紫杉醇作用中的作用。 具体目标2：分析紫杉醇和雌二醇之间在调节上述细胞系中凋亡方面的相互作用。实验将旨在阐明雌激素与紫杉醇激活的RAS/RAC/JNKK/JNK/AP1途径的相互作用。 具体目的3：鉴于雌激素可以调节几种可以调节凋亡的活性，因此我们将确定C-MYC，BC12，p53，p53，p300/cbp AKT在使用野生类型和主导（dn）兴趣基因的雌二醇的抗凋亡中的潜在作用。