Overexpression of TrkB promotes the progression of colon cancer.
Studies have confirmed that TrkB plays important roles in facilitating metastasis in various types of malignant tumors. In the present study, 30 cases of colon cancer and matched non-tumors were examined for the expression of TrkB by Western blot. The expression of TrkB was also examined in 90 colon tumor sections by immunohistochemical methods, and D2-40 staining was used to evaluate the correlation between TrkB expression and lymphatic vessel density. To investigate the effects of TrkB on the progression of colon cancer, siRNA specific for TrkB was transfected into LoVo cells, and proliferation, apoptosis and invasion of transfected cells were examined using MTT [3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide], flow cytometry and Transwell assays, respectively. Our results showed that TrkB was up-regulated in colon tumors compared with the non-tumorous counterparts, and the overexpression of TrkB was closely correlated with lymphatic vessel density (LVD) and metastasis. Inhibition of TrkB by siRNA increased the apoptotic rates of transfected cells, while the numbers of proliferative and invasive cells were decreased. In summary, our data suggest that overexpression of TrkB in colon cancer possibly plays roles in inhibiting apoptosis, promoting proliferation and invasion, facilitating tumor progression by lymphangiogenesis-associated metastasis.
Department of Ultrasound, The First Affiliated Hospital of China Medical University, Shenyang, China.
Yingjiao
Y
Yu
Siyang
S
Zhang
Xuemei
X
Wang
Zhiwei
Z
Yang
Guocheng
G
Ou
D017209:Apoptosis; D015153:Blotting, Western; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D003110:Colonic Neoplasms / Q000473:pathology*; D018450:Disease Progression; D006801:Humans; D007150:Immunohistochemistry; D009361:Neoplasm Invasiveness; D034741:RNA, Small Interfering / Q000235:genetics; D020813:Receptor, trkB / Q000032:analysis / Q000037:antagonists & inhibitors / Q000502:physiology*
D034741:RNA, Small Interfering; D020813:Receptor, trkB