[Radiotherapy for Bone Metastasis after Esophageal Cancer Surgery].

We examined the usefulness of radiotherapy for bone metastasis after esophageal cancer surgery. Between 2001 and 2016, we performed surgical resection for esophageal cancer in our department and 11 patients had postoperative bone metastases. Of these, 7 underwent radiotherapy. The median age was 71(60 to 76)years, with 5 males and 2 females. Six cases were squamous cell carcinoma and 1 case was adenocarcinoma. Metastatic sites included 3 vertebral bodies, 2 ribs, 2 skull bones, 1 ilium, 2 humerus, and 1 femur(there was overlap). Six cases also had other distant metastases. Three cases also underwent chemotherapy. Four of 7 cases(57%)showed reduction of metastatic lesions. The pain improvement rate was 57%. Radiation therapy for bone metastasis in esophageal cancer is thought to be effective for reduction of metastatic lesions and pain relief.

NOTCH1 activates the Wnt/ß-catenin signaling pathway in colon cancer.

PURPOSE AND METHODS: The translocation of ß-catenin/CTNNB1 to the nucleus activates Wnt signaling and cell proliferation; however, the precise mechanism underlying this phenomenon remains unknown. Previous reports have provided evidence that NOTCH1 is involved in the Wnt signaling pathway. Therefore, we sought to determine the mechanism by which NOTCH1 influences the Wnt/ß-catenin pathway. We constructed a vector expressing the NOTCH1 intracellular domain (NICD1) and transfected the vector into HCT116 which has low expression of NICD1. Furthermore, inhibition of NOTCH signal pathway in SW480 which has abundant NICD1 expression, was performed by transfection of siNICD1 or DAPT, gamma secretase inhibitor, treatment. In addition, we evaluated NICD1 and ß-catenin localization in colon cancer cell lines and in 189 colon cancer tissue samples and analyzed the correlation between the nuclear localization of NICD1 and the clinicopathological features of colon cancer patients. RESULTS: Immunohistochemical assays demonstrated that NICD1 and ß-catenin exhibited a similar localization pattern in colon cancer tissues. In addition, we found that NICD1 induced the translocation of ß-catenin to the nucleus and that NICD1 and ß-catenin co-localized in the nucleus. Overexpression of NICD1 increased luciferase activity of Wnt signal pathway. On the other hand, reduction of NICD1 reduced luciferase activity of Wnt signaling pathway. In the 189 analyzed colon cancer cases, multivariate COX regression analysis demonstrated the independent prognostic impact of nuclear localization of NICD1(p=0.0376). CONCLUSION: NOTCH1 plays a key role in the Wnt pathway and activation of NOTCH1 is associated with the translocation of ß-catenin to the nucleus.