A NOVEL ENDOCRINE DISRUPTING AGENT AND BREAST CANCER

描述（由申请方提供）：磨碎的玉米芯垫料和食物中的内分泌干扰（艾德）剂阻断大鼠的雄性和雌性性行为和性周期，并刺激乳腺癌和前列腺癌细胞增殖。在HPLC期间，这些试剂分离为两种组分（峰I-CM和峰II-CM）。峰I-CM（THF-二醇）中的促有丝分裂剂被鉴定为9，（12）-氧-10，13-二羟基硬脂酸和10，（13）-氧-9，12-二羟基硬脂酸的异构体混合物，其阻断雄性和雌性性行为和周期性。峰II-CM（LTX-二醇）中的促有丝分裂剂鉴别为白细胞毒素-二醇（LTX-二醇）和异白细胞毒素-二醇（iLTX-二醇）的异构体混合物，将在拟定研究中评估为ED。拟议的研究的目的是确定最具生物活性的合成THF-二醇和LTX-二醇异构体，定义它们在调节内分泌功能和乳腺癌细胞增殖中的相互作用的性质，并定义这些化合物在这些系统中调节的特定生化位点。将分别分离和鉴定最具活性的THF-二醇和LTX-二醇异构体（具体目标1），并确定它们是否以相加或协同方式刺激乳腺癌细胞增殖（细胞周期转换和细胞凋亡）并改变男性和女性性行为和周期性（具体目标2）。将通过GC/MS定量给予“艾德”剂量化合物的大鼠的组织和血液中THF-二醇和/或LTX-二醇异构体的浓度，并研究LTX-二醇是否为大鼠中THF-二醇的前体（具体目标3）。THF-二醇和LTX-二醇异构体促进DMBA诱发大鼠乳腺肿瘤的能力（具体目标4），并刺激增殖雌激素受体（ER）阳性（MCF-7）或ER阴性（细胞周期转换和凋亡）（MDA-MB-231细胞）体外或体内乳腺癌细胞将评估通过调节磷脂酶A2（PoA）、环氧合酶（考克斯）、脂氧合酶（LOX）和芳香酶（在裸鼠中）对小鼠（在裸鼠中）的作用（具体目标5）。已知白细胞毒素影响NO释放，并且LTX-二醇和THF二醇异构体可能通过破坏控制LHRH释放的一氧化氮（NO）依赖性途径来抑制女性性行为（脊柱前凸）。将对此进行评价（具体目标6）。如果THF-二醇和LTX-二醇通过控制LHRH释放和控制细胞增殖的脂肪生成产物来影响内分泌和细胞调节途径，则它们可能对实验动物的行为和生殖反应特征以及癌症生长率产生重大影响。在过去的十年中，亚油酸已经取代了我们饮食中的硬脂酸。作为亚油酸的代谢产物，THF-二醇和LTX-二醇的摄入量增加可能会影响人类的健康和发育。拟议的研究代表了确定最终确定这些化合物作用机制的靶向途径的关键一步。

DESCRIPTION (provided by applicant): Endocrine disruptive (ED) agents in ground corncob bedding and foods block male and female sexual behavior and cyclicity in the rat and stimulate breast and prostate cancer cell proliferation. These agents separate into two components (Peak I-CM and Peak II-CM) during HPLC. The mitogenic agents in Peak I-CM (THF-diols) were identified as an isomeric mixture of 9, (12)-oxy-10, 13-dihydroxystearic acid and 10, (13)-oxy-9, 12-dihydroxystearic acids which block male and female sexual behavior and cyclicity. The mitogenic agents in Peak II-CM (LTX-diols) were identified as an isomeric mixture of leukotoxin-diol (LTX-diol) and isoleukotoxin-diol (iLTX-diol) that will be assessed as EDs in the proposed studies. The objectives of the proposed research are to identify the most biologically active synthetic THF-diol and LTX-diol isomers, define the nature of their interaction in modulating endocrine function and breast cancer cell proliferation and define specific biochemical sites regulated by these compounds in these systems. The most active THF-diol and LTX-diol isomer will be isolated and identified separately (Specific Aim 1) and whether they act additively or synergistically to stimulate breast cancer cell proliferation (cell cycle transition and apoptosis) and modify male and female sexual behavior and cyclicity will be determined (Specific Aim 2). The concentrations of THF-diol and/or LTX-diol isomers in tissues and blood from rats given "ED" doses of the compounds will be quantified by GC/MS and whether LTX-diols are precursors to THF-diols in rats will be studied (Specific Aim 3). The abilities of THF-diol and LTX-diol isomers to promote dimethylbenz(a)anthracene (DMBA)-induced mammary tumors in rats (Specific Aim 4), and to stimulate the proliferation (cell cycle transition and apoptosis) of estrogen receptor (ER) positive (MCF-7) or ER-negative (MDA-MB-231 cells) breast cancer cells in vitro or in vivo (in nude mice) by modulating phospholipase A2 (PoA), cyclooxygenase (COX), lipoxygenase (LOX) and aromatase will be evaluated (Specific Aim 5). Leukotoxins are known to affect NO release and it is possible that LTX-diol and THFdiol isomers inhibit female sexual behavior (Lordosis) by disrupting nitric oxide (NO) dependent pathways controlling LHRH release. This will be evaluated (Specific Aim 6). If THF-diols and LTX-diols impact endocrine and cell regulatory pathways by controlling LHRH release and lipogenic products that control cell proliferation, they likely have a major impact on behavioral and reproductive response profiles and cancer growth rates in experimental animals. Over the last decade, linoleic acid has replaced stearic acid in our diet. As metabolites of linoleic acid, increased intake of THF-diols and LTX-diols may influence human health and development. The proposed studies represent a critical step in defining target pathways for ultimately determining the mechanism of action of these compounds.