Objective To summarize research status and mechanism about effects of carcinoma-associated fibroblasts (CAFs) on breast cancer stem cells. Method Relevant literatures about the relationship between the CAFs and breast cancer stem cells were collected and reviewed. Results CAFs were the majority type of the breast cancer stromal cells. The cancer stromal cell was also the important part of the tumor microenvironment, which could promote the proliferation, adhesion, invasion, and metastasis of the breast cancer. A subpopulation of cancer stem cells with the potentials of self-renewal and multi-directional differentiation in the breast cancer tissues might cause the tumor development. There was a phenotypic heterogeneity in the beast cancer stem cells, it was related to the tumor recurrence and therapy resistance. The CAFs could promote the formation of breast cancer stem cells through the epithelial mesenchymal transition and promote the transformation of tumor stem cell phenotype. More research needed to be done to prove these processes. Conclusion CAFs play an important role in formation of breast cancer stem cells and transformation of tumor stem cell phenotype, which might provide a new idea about treating breast cancer.
ObjectiveTo isolate cancer stem cells (CST) from human breast cancer cell line (MCF-7) and study their sensitivity toward oxidative stress.MethodsMCF-7 cells were cultured in serum-free suspension culture medium to identify cells forming the sphere phenotype. The morphological changes of MCF-7 cells were observed by inverted phase contrast microscope (compared with MCF-7 cells cultured in serum-free suspension culture medium). The expression of CST marker CD133 was detected by immunocytochemical staining in CST cell spheres (experimental group) with a diameter of 100 μm and MCF-7 cells (control group) with a fusion degree of 70%. The positive rate of CD133 was detected by flow cytometry in the third generation of tumor cells with diameter of 150 μm. The second generation of tumor globular cells (experimental group) with diameter of 150 μm and corresponding MCF-7 cells (control group) were taken to be damaged by 50 mol/L H2O2 for 120 minutes. The expression of DNA damage marker histone H2AX phosphorylation (γH2AX) was detected by immunocytochemical staining.ResultsInverted phase contrast microscopy showed that MCF-7 cells grew initially in a single-cell adherent state, then aggregated and grew in serum-free suspension culture medium, and finally formed CST cell spheres, while the control MCF-7 cells cultured in MCF-7 cell culture medium grew extensively and could not grow in suspension. Fluorescence microscopy showed that the expression of CD133 in MCF-7 cells of control group was negative, while that in experimental group was positive. Flow cytometry showed that CD133 was positive in CST cells, and the positive rate was 92%. Inverted fluorescence microscopy showed that the expression of γH2AX in CST tumor spheres of experimental group was significantly lower than that in MCF-7 cells of control group after 120 minutes of H2O2 injury.ConclusionSerum-free suspension culture medium can produce globular CST cells from MCF-7 tumor cell line, which have strong antioxidant damage.
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.
ObjectiveTo investigate the expression and clinical significance of octamer-binding transcription factor 4(Oct-4) in gastric cancer (GC) tissues with meta-analysis. MethodsPubMed, EMBASE, Web of Science, CBM, VIP, CNKI, and WanFang Database were searched from their establishment to Oct.2012 for related studies, to investigate the relationship between expression of Oct-4 and the clinicopathological characteristics of GC.After evaluating methodo-logical quality of studies that met the inclusion criteria, RevMan 5.1 software was used to data analysis. ResultsEight studies which enrolled 623 cases of GC were identified.The results of the meta-analysis showed that, as for the positive expression rate of Oct-4, there were significant differences between GC tissues and normal stomach tissues (OR=37.50, 95% CI: 4.76-295.51, P < 0.01), as well as the cell differentiation (OR=0.27, 95% CI: 0.16-0.45, P < 0.01), for that the positive expression rate of Oct-4 in low differentiation of gastric cancer tissues was higher than those of moderate-high differentation group.But there were no significant differences between GC tissues with lymph node metastasis and non-lymph node metastasis (OR=2.09, 95% CI: 0.63-6.94, P=0.23), as well as Ⅰ-Ⅱ stage and Ⅲ-Ⅳ stage (OR=0.62, 95% CI: 0.25-1.54, P=0.30) of GC tissues. ConclusionsOct-4 may participate in the whole course of carcinogenesis of GC, but the relationship between expression of Oct-4 and lymph node metastasis as well as the TNM stage of GC is unclear, which needs more high quality studies to explore the question clearly.
ObjectiveTo determine the expressions of Lgr5 protein and Ki-67 protein in gastric cancer tissues, and to analyze the possible function in the carcinogenesis and development of gastric cancer.MethodsThe SABC immunohistochemical method was adopted to examine the expressions of Lgr5 protein and Ki-67 protein in the 69 paraffin slices of gastric cancer from the patients, with the adjacent normal gastric tissue as the control group. The statistical relationship between the expressions of these two kinds of proteins and clinicopathologic features of gastric cancer was examined respectively.ResultsIn the gastric cancer tissue group, the expressions of Lgr5 protein and Ki-67 protein upregulated in comparison to the adjacent normal gastric tissue group [Lgr5 protein: 87.0% (60/69) versus 16.7% (5/30), χ2=45.81, P<0.001; Ki-67 protein: 79.7% (55/69) versus 36.7% (11/30), χ2=17.43, P<0.001]. The expressions of Lgr5 protein and Ki-67 protein all upregulated in the N1–N3 stage groups, lowly differentiated+undifferentiated groups and positive Helicobacter pylori (HP) groups. The expression of Lgr5 protein upregulated in the T3+T4 stage groups in comparison to T1+T2 stage groups, while, no significant relationship was found in the expression of Ki-67 protein and tumor T staging. No significant relationship was found between the gender or metastasis and the expression of these two proteins. There was a positive correlation between the Lgr5 protein expression and the Ki-67 protein expression in the gastric cancer (rs=0.340, P=0.004).ConclusionsIn the development progress of gastric cancer, the Lgr5 protein might get involved in the mechanism of tumor invasion, lymph nodal metastasis, and low differentiation. Ki-67 protein might get involved in the mechanism of lymph nodal metastasis and low differentiation. The two proteins, together with the HP infection, might play a synergistic role in tumorigenesis and development.
Objective To explore the tumorigenicity and expressions of dishevelled 3 (DVL3) in HCT116 cells and HCT116 spherical cells. Methods Human colorectal tumor HCT116 cells were cultured in the serum-free culture medium for HCT116 spherical cells. Through the subcutaneous tumor experiment in nude mice and clone formation assay, we observed the tumor growth and colony formation ability of the two kinds of cells in vivo and in vitro. The Western blotting experiment was utilized to detect the expressions of DVL3 in these two kinds of cells. Results ① Colonyformation: the mean value of colony formation rate in the HCT116 cells group was 3.78%, and the mean value of fcolony formation rate in the HCT116 spherical cells group was 28.67%, which was higher in the HCT116 spherical cells group (t=21.16, P<0.05). ② Tumorigenicity in nude mice: 11 nude mice with tumor formation were observed in the HCT116 cells group, and the tumor formation rate was 55.0%; 18 nude mice with tumor formation were observed in the HCT116 spherical cells group, and the tumor formation rate was 90.0%, the tumor formation rate of the HCT116 spherical cells group was higher (P=0.039). The tumor volume of the HCT116 cells group was (92±31) mm3, and the tumor volume of HCT116 spherical cells group was (298±85) mm3, the tumor volume of the HCT116 spherical cells group was larger (t=9.27, P<0.05). ③ The expression of DVL3: the expression level of DVL3 in HCT116 cells was 0.12±0.05, and expression level of DVL3 in HCT116 spherical cells was 0.35±0.10, the expression level of DVL3 in HCT116 spherical cells was higher (t=4.31, P<0.05). Conclusions The HCT116 spherical cells have stronger colonization and tumorigenicity than the HCT116 cells. It has been speculatd that the high expression of DVL3 may be closely related with the stronger tumorigenicity.
Objective To analyze the advances of cancer stem cell (CSC) in recent years, and to propose a prospect for CSC research and cancer therapy. Methods Articles about important advances of CSC theory and cancer therapy were reviewed, and then selected and summarized. Results In 2001, CSC was first put forward as a concept, till now, which has been confirmed in many tissues. In recent years, efforts were dedicated to such topics including: identification of CSC in sol id tumors, the origin of CSC, its niche and growth mechanism, cancer therapy, etc. According to the CSC theory, traditional therapeutic methods have deficiencies, and new treatment targeting CSC may thoroughly el iminate tumors. Conclusion At present, CSC theory is still controversial, while it proposed revolutionary methods and directions for the therapy of cancer.