Characterization of tumorigenic features of uterine leiomyoma

利用该子宫平滑肌瘤体外系统研究了GnRH类似物（GnRH）治疗期间平滑肌瘤收缩的机制。先前，我们证明平滑肌瘤细胞形成球状聚集，我们将其命名为“球状聚集（BLAs）”。由于子宫平滑肌瘤细胞的球状聚集在体内似乎与子宫平滑肌瘤的特征接近，因此我们可以评估目前用于子宫平滑肌瘤化疗的GnRH类似物的有效性。结果表明，GnRH类似物的加入使平滑肌瘤细胞的球状聚集物消失。结果还表明，GnRH直接与培养的平滑肌瘤细胞结合，并且在平滑肌瘤细胞中存在GnRH受体以及GnRH的表达。此外，添加小剂量和短剂量的GnRH类似物刺激平滑肌细胞的增殖，更多的是平滑肌瘤，但高剂量GnRH类似物长期治疗抑制了G1期细胞周期晚期相关基因的表达。这些结果提示GnRH类似物可能直接调节子宫平滑肌瘤的生长，子宫平滑肌瘤的体内系统有助于评价目前用于子宫平滑肌瘤化疗药物的疗效。肥大细胞（MCs）广泛分布于大多数人体组织和肿瘤中，包括平滑肌瘤。GnRHa最近被应用于平滑肌瘤的治疗。为了阐明MCs在平滑肌瘤中的作用，我们分析了平滑肌瘤中MCs的数量与组织学特征之间的关系，并比较了未经治疗的平滑肌瘤中MCs的数量与经GnRHa治疗的平滑肌瘤中MCs的数量。结果显示，未经治疗的平滑肌瘤中MCs数量分布广泛，但胶原基质少、细胞度高、T2加权MR图像强度高的平滑肌瘤中MCs较多。此外，GnRHa高度收缩的平滑肌瘤中含有较多的MCs，且这些MCs在GnRHa治疗前在平滑肌瘤中已经存在，而GnRHa并未使这些MCs增加。这些结果提示，MCs可能与平滑肌瘤的增殖活性有关，并在GnRHa治疗中发挥缩小大小的作用。ER和PR在所有ULs中均有免疫组织化学表达。无论月经周期的哪个阶段，PR都在UL中明确表达。在CL、UMP和BL中也观察到PR的这种染色模式，尽管BL对ER的染色是可变的。与这些肿瘤相比，LMS中ER和PR的表达均明显降低。RT-PCR扩增ER和PR转录本的结果与免疫组化结果一致。LMS中Ki-67阳性细胞数量异常，显著高于UMP、BL、CL和UL。P53免疫反应性较低

The mechanisms regarding to the shrinkage of leiomyoma during the treatment with GnRH analogue (GnRH) analogue have been investigated using this in vitro system of uterine leiomyoma. Previously, we demonstrated that the cells from leiomyoma formed ball-like aggregations which we named "ball-like aggregations (BLAs)". Since the ball-like aggregations of cells from leiomyoma seem to be close to the features of uterine leiomyoma in vivo, this allows us to evaluate the efficiency of GnRH analogue currently used for chemotherapy of uterine leiomyomas. The results showed that the addition of GnRH analogue caused disappearance of the figure of the ball-like aggregations of cells from leiomyoma. The results also showed that GnRH directly binds to the cultured cells from leiomyoma and that the existence of GnRH receptor as well as GnRH expression in the cells from leiomyomas. Furthermore, the addition of small and short doses of GnRH analogue stimulates the proliferation of smooth muscle cells … More of leiomyoma, but the late G1 phase cell cycle related genes' expression were suppressed by the addition of high doses GnRH analogue for long treatment. These results suggested that GnRH analogue may directly regulate the growth of uterine leiomyomas, and that the in vivo system of uterine leiomyoma is useful to evaluate the efficiency of drugs currently used for chemotherapy of uterine leiomyomas. Mast cells (MCs) are widely distributed in most human tissues and neoplasms, including a leiomyoma. GnRHa has been recently applied for the treatment of a leiomyoma. To elucidate the role of MCs in a leiomyoma, the relationship between the number of MCs in leiomyomas and the histological features was analyzed, furthermore, the number of MCs in untreated leiomyomas was compared with that of MCs in the leiomyomas treated with GnRHa. The results showed that the number of MCs in untreated leiomyomas was widely distributed, but there were more Mcs in leiomyomas with fewer collagen matrix, with higher cellularity, and with high intensity of T2 weighted MR image. In addition, the leiomyomas which had highly shrinked with GnRHa contained a larger number of MCs, and these MCs were not increased by GnRHa, but before therapy they had existed in the leiomyomas The findings suggest that MCs may associated with prolierative activity of leiomyoma and play a role in shirnkage of the size in GnRHa therapy.Both ER and PR are immunohistochemically expressed in all ULs. PR was definitely experssed in UL irrespective of the phase of the menstrual cycle. This staining pattern of PR was also observed in CL,UMP and BL,although BL showed variable staining for ER.Compared to these tumors, the expression of both ER and PR was markedly reduced in LMS.The results of ER and PR transcripts by RT-PCR amplification were compatible with those of immunohistochemistry. The number of Ki-67 positive cells in LMS was extraordinary and significantly higher than in UMP,BL,CL and UL.P53 immunoreactivity was seen Less