Objective To review the role of mTOR signal pathway in chemo-resistance of gastric cancer. Methods Domestic and international publications related mTOR signal pathway in chemo-resistance of gastric cancer in recent years were collected and reviewed. Results mTOR was a central signaling molecule of mTOR signal pathway， which regulated key cellular processes such as cell growth， cell proliferation， cell metabolism， and angiogenesis. Signaling molecules of mTOR signal pathway were overexpressed in gastric cancer. Moreover， mTOR signal pathway might play an important role in chemo-resistance of gastric cancer， and tumor stem cells were involved in it too. Conclusion As mTOR signal pathway plays an important role in chemo-resistance of gastric cancer， the combination of mTOR inhibitors and chemotherapy drugs may overcome the chemo-resistance of gastric cancer.
Objective To isolate and purify the melanoma stem cells (MSC) in choroidal melanoma OCM-1 cells. Methods OCM-1 cells were resuscitated, and after cultured in standard Dubecco's modifided Eagle's medium (DMEM)/F12, they were cultured in serum-free medium (SFM). The cultured MSC were isolated and purified, and the positive rate of CD133, the specific markers of neurostem cells, was observed by flow cytometry (FCM). The 6th generation of the cells were stained by musashi-1 immunocytochemistry, and the rate of the positive cells was observed under the microscope. Results After the Adherent OCM-1 cells cultured in SFM, the number of the adherent number decreased obviously. The cells at the 6th generation grew as the suspended gobbets, which represented the typical grow manner of the stem cells. Positive CD133 could be found in the cells of different generations, which was 2.5％, 21.7％, and 57.8％ in the non-isolated OCM-1 cells, the 1st generation of isolated cells, and the 2nd generation cells, respectively. The positive rate of CD133 in the cells at the sixth generation was 79.8% with b positive expression of musashi-1. Conclusion MSC is in the human choroidal melanoma OCM-1 cells. The suspended stem cells may be purified by limited differentiation and serial passage in SFM. (Chin J Ocul Fundus Dis, 2007, 23: 87-90)
Objective To investigate the expressions of CD90, IGF1R, and hTERT protein in hepatocellular carcinoma, and the correlations of each other in the development of carcinoma. Methods The expressions of CD90, IGF1R, and hTERT protein in hepatocellular carcinoma were detected by S-P immunohistochemical staining, 20 cases of normal liver tissues were collected as contrast, and to compare the relations between expression and prognosis or survival rate. Results The positive rate of CD90, IGF1R, and hTERT protein in hepatocellular carcinoma group were obviously higher than that in contrast group（P＜0.05）, which was 63.9% vs. 0, 52.8% vs.5.0%, and 47.2% vs.0, respectively. The positive rate of CD90, IGF1R, and hTERT protein were higher in UICC Ⅲ-Ⅳ stage group than that in UICC stage Ⅰ-Ⅱ group（P＜0.05）, which was 79.2% vs.33.3%, 70.8% vs.16.7%, and 62.5% vs.16.7%, respectively. There was a statistically significant positive correlation observed between the expressions of CD90 and IGF1R protein （Kendall’s tau-b=0.563 1, P＜0.05）, so it was with CD90 and hTERT protein （Kendall’s tau-b=0.363 6, P＜0.05）. The survival rates of positive expressions of CD90, IGF1R, and hTERT protein were lower than negative expressions of CD90, IGF1R, and hTERT（P＜0.05）, which was 21.7% vs.50.0%, 17.6% vs.43.8%, and 20.0% vs.38.9%, respectively. Conclusions The expressions of CD90, IGF1R, and hTERT may have correlations with the progress of HCC, and may serve as a marker for HCC prognosis potentially.
Objective To investigate the clinical outlook of hepatic stem cells and its relations with liver cancer. Methods The literatures of recent years on the studies of hepatic stem cells were reviewed. Results Liver cancer may consist of cells of various differentiation grades and it may result from the perodifferentiated hepatic stem cells or abnormal differentiated cells. Conclusion The hypothesis of hepatic stem cells has been identified extensively. Further study maybe helpful for revealing the origin, carcinogenesis of hepatic cancer, and may also be useful for the understanding of the mechanism of metastasis.
Objective To summarize the status of tumor stem cells study in solid tumors. Methods Domestic and international publications on the study of tumor stem cells in solid tumors in recent years were collected and reviewed. Results Tumor stem cells exactly existed in solid tumors and played a very important role in tumorgenesis. Conclusion Tumor stem cells bring a new broad of perspective on solid tumor study.