Department of Obstetrics and Gynecology, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
Exp Mol Pathol. 2011 Oct;91(2):563-8. doi: 10.1016/j.yexmp.2011.06.002. Epub 2011 Jul 8.
We previously reported the overexpression of lipocalin2 (LCN2), a 25kDa secretory protein involved in iron-transportation, in endometrial carcinoma and its possible contribution to endometrial carcinogenesis. Recently, a specific receptor for LCN2, solute carrier family 22 member 17 (SLC22A17), was identified. The present study was undertaken to investigate the expression of SLC22A17 in endometrial carcinoma.
The expression of the SLC22A17 and LCN2 proteins was examined immunohistochemically using 69 cases of endometrial carcinoma and adjacent normal endometrial tissues. Immunoreactivity was evaluated according to the percentage of positive cells and described as a positivity index (PI, full score 100).
The expression of SLC22A17 was negligible in normal endometria, but positive staining for SLC22A17 (PI≧1) was observed in 35 cases of endometrial carcinoma. The PI for SLC22A17 was significantly higher in cases with histological grade 3 (P<0.0005), advanced FIGO stage (P=0.002), deep myometrial invasion (P=0.029), positive lymph-vascular space invasion (P=0.029), positive intraperitoneal cytology (P=0.020) and adnexal metastasis (P=0.029). The expression of SLC22A17 and LCN2 was positively correlated with a significant difference (P=0.002), and the patients who overexpressed both SLC22A17 and LCN2 showed poorer survival than those without the expression of SLC22A17 or LCN2 (P=0.002). Moreover, the overexpression of both SLC22A17 and LCN2 was indicated to be an independent prognostic factor by multivariable analysis.
These results suggested that SLC22A17, in cooperation with LCN2, to be involved in the acquisition of aggressive behavior among endometrial carcinoma cells.
我们之前报道过脂联素 2（LCN2）的过表达，LCN2 是一种 25kDa 的分泌蛋白，参与铁转运，在子宫内膜癌中及其可能促进子宫内膜癌发生。最近，LCN2 的一种特定受体溶质载体家族 22 成员 17（SLC22A17）被鉴定出来。本研究旨在研究 SLC22A17 在子宫内膜癌中的表达。
使用 69 例子宫内膜癌和相邻正常子宫内膜组织，通过免疫组织化学检测 SLC22A17 和 LCN2 蛋白的表达。根据阳性细胞的百分比评估免疫反应性，并描述为阳性指数（PI，满分为 100）。
正常子宫内膜中 SLC22A17 的表达可以忽略不计，但在 35 例子宫内膜癌中观察到 SLC22A17 的阳性染色（PI≧1）。SLC22A17 的 PI 在组织学 3 级（P<0.0005）、FIGO 晚期（P=0.002）、深肌层浸润（P=0.029）、淋巴管血管间隙浸润阳性（P=0.029）、腹腔细胞学阳性（P=0.020）和附件转移（P=0.029）的病例中显著更高。SLC22A17 和 LCN2 的表达呈正相关，差异有统计学意义（P=0.002），并且同时过表达 SLC22A17 和 LCN2 的患者的生存情况比不表达 SLC22A17 或 LCN2 的患者差（P=0.002）。此外，多变量分析表明，SLC22A17 和 LCN2 的过表达是独立的预后因素。
这些结果表明，SLC22A17 与 LCN2 合作，参与子宫内膜癌细胞获得侵袭性行为。
