講演情報
[OE1-2]乳がんの新規バイオマーカー、治療標的分子URST7の同定
○Mbugua Regina1,2, 高野 淳1,2,3, Tsevegjav Bayarbat1,2, 宮城 洋平4, 醍醐 弥太郎1,2,3 (1.滋賀医科大学 臨床腫瘍学講座, 2.滋賀医大・先端がん研究センター, 3.東大・医科研・抗体ワクチンセンター, 4.神奈川がんセンター・がん分子病態学部)
Breast cancer is one of the highly frequent cancers in women and also causes the greatest number of cancer-related deaths worldwide. Despite a sustained decline in mortality rates and significant improvement in clinical outcome for patients with breast cancer, the efficacy of the current standard therapies is limited and prognosis of the disease is still poor. Therefore, new biomarkers and therapeutic targets for breast cancer treatments are eagerly needed. Our study aims to evaluate the role of URST7 (Up-regulated in solid tumor 7) as a prognostic biomarker and therapeutic target for breast cancer. Real-time PCR and western-blotting showed that URST7 mRNA and its gene product were highly expressed in the majority of breast cancer cell lines, but barely detected in normal breast epithelial cells. Tissue microarray analysis revealed that URST7 was expressed in 204 of 252 breast cancers. Positivity of URST7 staining was significantly associated with poorer prognosis for breast cancer patients (P = 0.0102 by log-rank test). A multivariate analysis indicated that URST7 expression was an independent prognostic factor for patients with breast cancer. Suppression of URST7 by siRNAs inhibited breast cancer cell growth and induced the apoptosis of cancer cells. Enhanced URST7 expression led to a significant increase in cancer cell proliferation. These results suggest that URST7 could be a potential biomarker and therapeutic target for breast cancer.