Study for a tumor suppressive serpin, maspin in cervical cancer

宫颈癌中抑癌性丝氨酸蛋白酶抑制剂（maspin）的研究

基本信息

批准号：
20591949
负责人：
NAWATA Shugo
金额：
$ 3万
依托单位：
Yamaguchi University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2008
资助国家：
日本
起止时间：
2008 至 2010
项目状态：
已结题

项目摘要

Our series of recent study has demonstrated that there is a distinct difference between normal and malignant uterine cervical squamous epithelial tissues in the molecular heterogeneity of the tumor-related serine proteinase inhibitor (serpin), Squamous Cell Carcinoma (SCC) antigen. On the other hand, although maspin, identified as a 42-kDa unique tumor suppressive serpin in breast cancer, has multifaceted biological functions by interacting with various target molecules under physiological and pathological conditions including tumor progression, oxidative stress and so on, it is unknown what post-translational modification contributes the specific binding affinity of maspin to target molecules, such as glutathione S-transferase (GST). The aim of this study is therefore to analyze the molecular heterogeneity of maspin and identify its modification in MCF-10A cell, which is known to express abundant maspin protein, using various electrophoretic analyses. We successfully identified the novel form of endogenous maspin generated by intramolecular disulfide-bonded linkage under oxidative stress. Furthermore, glutathione beads pull-down assay revealed that intramolecular disulfide-bonded maspin lost the binding activity with endogenous GST, indicating that intramolecular disulfide-bonded maspin might have some distinct properties under oxidative stress, although the precise biological significance of this modification remains elusive. The western blot analysis using cervical primary cancer tissues showed that maspin expression levels in cervical cancer patients with pelvic lymph node metastasis were relative low compared to those with no pelvic lymph node metastases, suggesting that the suppression or post-translational modification of the tumor suppressive serpin, maspin might be related to tumor progression in cervical cancer.

我们最近的一系列研究表明，在肿瘤相关的丝氨酸蛋白酶抑制剂（SERPIN），鳞状细胞癌（SCC）抗原的分子异质性中，正常和恶性子宫宫颈上皮组织之间存在明显差异。另一方面，尽管Maspin在乳腺癌中被确定为42 kDA独特的肿瘤抑制serpin，但通过在生理和病理条件下与各种靶标分子相互作用，具有多方面的生物学功能S-转移酶（GST）。因此，这项研究的目的是分析Maspin的分子异质性，并使用各种电泳分析在MCF-10A细胞中确定其在MCF-10A细胞中的修饰，该细胞已知可以表达丰富的Maspin蛋白。我们成功地确定了氧化应激下分子内二硫键键合的新型内源性maspin的新形式。此外，谷胱甘肽珠下拉测定法表明，分子内二硫键键合的maspin失去了与内源性GST的结合活性，表明在氧化应激下可能具有某些不同的氧化应激，尽管这种修饰的精确生物学意义仍然存在。使用宫颈原发性癌症组织进行的蛋白质印迹分析表明，与没有骨盆淋巴结转移的宫颈淋巴结转移的宫颈癌患者的MASPIN表达水平相对低，这表明抑制或抑制性抑制性塞普蛋白的抑制作用或后翻译后的抑制后可能与Tumor抑制性毒性相关。