Kasamatsu Atsushi, Uzawa Katsuhiro, Nakashima Dai, Koike Hirofumi, Shiiba Masashi, Bukawa Hiroki, Yokoe Hidetaka, Tanzawa Hideki
Department of Clinical Molecular Biology, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670, Japan.
Int J Mol Med. 2005 Aug;16(2):269-73.
Oral squamous cell carcinomas (OSCCs), a major public health problem worldwide, are the most common neoplasms of the head and neck. The most important prognostic indicator for patients with OSCC is metastasis to cervical lymph nodes or distant organs. Galectin-9 is correlated with cellular adhesion and aggregation in melanoma cells. To investigate expression levels of galectin-9 mRNA and protein, we performed qRT-PCR and Western blot analyses on OSCC cell lines (Ca9-22, HSC-2, and HSC-3) and normal oral keratinocytes (NOKs). Galectin-9 mRNA and protein were commonly down-regulated in OSCC cell lines compared with NOKs. We further analyzed Ca9-22, which had the lowest expression of galectin-9. We then transfected the galectin-9 cDNA into Ca9-22 cells to examine whether overexpression of galectin-9 increases cellular adhesion in vitro. An adhesion assay using a fibronectin and collagen I coating plate revealed an increased cellular adherence ratio in overexpressed galectin-9 cells compared with nontransfected cells (p < 0.05). The data suggest that galectin-9 is correlated with oral cancer cell-matrix interactions and may therefore play an important role in the metastasis of OSCCs.
口腔鳞状细胞癌（OSCC）是全球主要的公共卫生问题，是头颈部最常见的肿瘤。OSCC患者最重要的预后指标是颈部淋巴结或远处器官转移。半乳糖凝集素-9与黑色素瘤细胞中的细胞黏附和聚集相关。为了研究半乳糖凝集素-9 mRNA和蛋白的表达水平，我们对OSCC细胞系（Ca9-22、HSC-2和HSC-3）和正常口腔角质形成细胞（NOK）进行了qRT-PCR和蛋白质印迹分析。与NOK相比，OSCC细胞系中半乳糖凝集素-9 mRNA和蛋白普遍下调。我们进一步分析了半乳糖凝集素-9表达最低的Ca9-22细胞。然后，我们将半乳糖凝集素-9 cDNA转染到Ca9-22细胞中，以检测半乳糖凝集素-9的过表达是否会增加体外细胞黏附。使用纤连蛋白和I型胶原包被板进行的黏附试验显示，与未转染细胞相比，过表达半乳糖凝集素-9的细胞的细胞黏附率增加（p < 0.05）。数据表明，半乳糖凝集素-9与口腔癌细胞-基质相互作用相关，因此可能在OSCC转移中起重要作用。
