Analysis of signal transduction associate with carcinogenesis and progression in endometrial and ovarian carcinoma.

(1)探讨雌激素受体(ER)在[12Val]K-RAS突变体转化NIH3T3细胞过程中的生物学意义。孕激素受体(PR)与突变型K-RAS共表达可抑制细胞的致瘤性，抑制ER的激活。与ER互补的反义寡核苷酸可抑制K12 2V细胞的增殖和转化表型。这些观察结果支持了ER在Ras介导的细胞转化中的重要性。(2)我们比较了携带野生型(Ishikawa细胞)和突变(HHUA细胞)K-ras的子宫内膜癌细胞对表皮生长因子(EGF)的生长反应。首先，我们确定K-ras突变并不显著影响这些癌细胞中EGF受体的表达水平。接下来，我们观察到EGF可以刺激石川细胞的生长，但不能刺激HHUA细胞的生长。此外，表皮生长因子导致ISI…中RAS-GTP水平的升高更多的卡瓦细胞，但不是HHUA细胞。然而，将突变但不正常的K-ras基因导入石川细胞，使其对EGF生长刺激没有反应。因此，突变的K-ras单独存在可以调节子宫内膜癌细胞对EGF的生长反应。最后，我们观察到EGF受体酪氨酸激酶活性的抑制剂可以阻止Ishikawa细胞的软琼脂集落形成，但不能阻止HHUA或突变的K-ras(12V)转基因的Ishikawa细胞。综上所述，这些结果表明突变的K-ras导致对EGF刺激的反应性丧失，EGF受体功能对于突变的RAS阳性子宫内膜癌细胞的生长是必不可少的。(3)肝细胞生长因子是一种多功能的生长因子，对上皮细胞具有增殖、运动、侵袭和形态发生等多方面的生物学作用。腹膜扩散是卵巢癌进展的关键，我们的研究发现肝细胞生长因子可诱导卵巢癌细胞的迁移和侵袭。在这里，我们还证明了肝细胞生长因子刺激其受体的自磷酸化，随后激活RAS-MAP激酶级联。此外，ras显性负性腺病毒感染卵巢癌细胞降低了肝细胞生长因子诱导的运动和侵袭活性。这些结果表明，RAS-MAP激酶通路在卵巢癌的进展中起重要作用，特别是在腹膜扩散过程中。较少

(1)We investigated the biological significance of estrogen receptors (ER) in NIH3T3 cell transformation by the [12Val] K-Ras mutant. This mutant enhanced the steady state level and transcriptional activity of ER.Co- expression of progesterone receptor (PR) with mutant K-Ras led to suppression of tumorigenicity and inhibition of the activation of ER.The antisense oligomers complementary to the ER suppressed proliferation and transformed phenotypes of K1 2V cells. These observations support the importance of ER in Ras-mediated cell transformation.(2)We compared the growth response of endometrial carcinoma cells harboring wild type (Ishikawa cells) or mutated (HHUA cells) K-ras to epidermal growth factor (EGF). First, we determined that K-ras mutation did not significantly affect the level of the EGF receptor expressed in these carcinoma cells. Next, we observed that EGF could stimulate the growth of Ishikawa, but not HHUA cells. Furthermore, EGF caused elevation of Ras-GTP levels in Ishi … More kawa, but not HHUA cells. However, the introduction of mutated, but not normal, K-ras into Ishikawa cells rendered them nonresponsive to EGF growth stimulation. Thus, the presence of mutated K-ras alone can modulate the growth response of endometrial carcinoma cells to EGF.Finally, we observed that an inhibitor of the EGF receptor tyrosine kinase activity could prevent soft agar colony formation of Ishikawa cells, but not HHUA or mutant K-ras(12V)-transfected Ishikawa cells. Taken together, these results suggest that mutated K-ras causes a loss of responsiveness to EGF stimulation and that EGF receptor function is dispensable for the growth of mutant Ras-positive endometrial carcinoma cells.(3)Hepatocyte growth factor is a multifunctional growth factor which has pleiotrophic biological effects on epithelial cells such as proliferation, motogenesis, invasiveness, and morphogenesis. Peritoneal dissemination is critical for progression of ovarian cancer, and our study revealed that hepatocyte growth factor induces migration and invasion of ovarian cancer cells. We also demonstrated here thet hepatocyte growth factor stimulates autophosphorylation of its receptor which is followed by activation of the Ras-MAP kinase cascade. Moreover, infection of ovarian cancer cells with ras dominant-negative adenovirus reduced hepatocyte growth factor-induced motogenic and invasive activity. These results suggested that the Ras-MAP kinase pathway plays an important role in progression of ovarian cancer, specifically in peritoneal dissemination. Less