In this study, we aimed to investigate the influences of conditioned medium from human umbilical vein endothelial cells (HUVEC) on cancer stem cell phenotype of human hepatoma cells. HUVEC and human hepatoma cells (MHCC97H) were cultured, respectively, and then the MHCC97H cells were co-cultured with conditioned medium from HUVEC (EC-CM) with Transwell system. Anti-cancer drug sensitivity, colony-formation, migration/invasion ability, expression of cancer stem cell marker and sphere formation were performed to determine the cancer stem cell phenotype in MHCC97H cells. We found that MHCC97H cells co-cultured with EC-CM exhibited significantly higher colony-formation ability and lower sensitivity of anti-cancer drugs 5-FU and Cis. Transwell assay showed that treatment with EC-CM obviously increased migration and invasion of MHCC97H cells. Moreover, increased sphere forming capability and expression of CD133 in MHCC97H cells were observed after co-cultured with EC-CM. These results suggested that EC-CM could promote cancer stem cell phenotype of hepatoma cells.
ObjectiveTo explore and hypothesize the potential mechanisms of cancer stem cell(CSC) in peritoneal metastasis of gastric cancer. MethodsThe databases of PubMed and CNKI were searched, and relevant literatures were reviewed to draw out systematic hypotheses. ResultsMetastatic cancer stem cell(MCSC) was the subpopulation of CSC with the capacity of metastasis, had still not been well investigated. MCSC transfer was the tendency of migration and planting to specific target tissue by multi-steps of "homing" process. Peritoneal metastasis of gastric cancer was a simplified "homing" process, and we thinked that the key steps were adhesion, migration, and niche establishment of MCSC in peritoneum. That capturing human MCSC of peritoneal metastases in gastric cancer and identifying its stemness feature to determine high tumorigenicity and high invasive ability of it were the important research fields. ConclusionMCSC might play certain role in multiple processes in peritoneal metastasis of gastric cancer, but currently it's lack of relevant researches.
Lung cancers are highly heterogeneous and resistant to available therapeutic agents, with a five-year survival rate of less than 15%. Despite significant advances in our knowledge of the genetic alterations and aberrations in lung cancer, it has been difficult to determine the basis of lung cancer's heterogeneity and drug resistance. Cancer stem cell model has attracted a significant amount of attention in recent years as a viable explanation for the heterogeneity, drug resistance, dormancy, recurrence and metastasis of various tumors. At the same time, cancer stem cells have been relatively less characterized in lung cancers. This review summarizes the current understanding of lung cancer stem cells, including their molecular features and signaling pathways that drive their stemness. This review also discusses the prognosis of lung cancer and its relationship with lung cancer stem cell, in an effort to eradicate these cells to combat lung cancer.
Esophageal carcinoma is a kind of common malignant tumor in the digestive tract. Although a lot of basic researches and clinical trials have been carried out all over the world, neither the diagnostic level nor the therapeutic effects have been obviously improved. The 5-year survival rate of esophageal cancer patient is still lower than that of other malignant tumors. Up to now, some frontier researches consider that the reason of the esophageal carcinoma being difficult to cure is related to the stem cells in it. Elimination or suppression of these stem cells may bring new hope for the treatment of esophageal cancer. This article generally introduces the specific markers, separation and indentification methods about the esophageal cancer stem cell. The targeted therapy is also mentioned.
Objective The aim is to sort CD90+ subpopulation cells in human liver cancer cell lines and investigate efficiency of magnetic cell sorting (MACS) on sorting the liver cancer stem cells. Methods ①Expressions of CD90. Immunohistochemical method was used to determine the expressions of CD90 in normal liver tissues in 8 cases, liver cancer and adjacent liver cancer tissues in 58 cases. ②Screened the cell lines. Huh-7, MHCC97-H, Bel-7402, and SMMC-7721 cell lines were divided into blank control group and experimental group (5.5×105 cells per hole, 1 hole), cells of the experimental group were added with 5 μL CD90–PE while cells of the blank control group were treated with 5 μL CD90–PE non fluorescent antibody. Determined the proportion of CD90+ cells in the 2 groups by flow cytometry (FCM). ③MACS. Huh-7 and MHCC97-H cell lines were labeled with magnetic beads respectively and sorted by MACS, 1 mL cell suspensionsorted by magnetic sorting (MS) was collected as CD90– group, and 1 mL PBS after MS wash was collected as CD90+ group, as well as blank control group and experimental group. Determined the proportion of CD90+ cells in 4 groups by FCM. Two times of MACS were performed in Huh-7 cells. ④Serum free culture and serum culture. Huh-7 cells were divided into serum-free culture group and serum culture group (1 hole), and proportions of CD90+ cells were determined by FCM at 1 week after culture. Results ①The positive rate of CD90 was 0 (0/8), 65.5% (38/58), and 20.7% (12/58) in normal liver tissues, liver cancer tissues, and adjacent liver cancer tissues respectively, and the positive rate of CD90 was higher in liver cancer tissues than those of normal liver tissues (χ2=6.78, P<0.05) and adjacent liver cancer tissues (χ2=20.83, P<0.05). ②For Huh-7, MHCC97-H, SMMC-7721, and Bel7402 cell lines, the proportions of CD90+ cells in the experimental group was 0.851%, 1.090%, 2.710%, and 4.050% respectively, the proportions of CD90+ cells in the blank control group was 0.241%, 0.688%, 1.890%, and 2.080% respectively, so we chose Huh-7 and MHCC97-H cell lines to perform MACS. ③Results of MACS for Huh-7 cell line. For the first MACS, the proportions of CD90+ cells in the blank control group, experimental group, CD90– group, and CD90+ group was 0.241%, 0.851%, 0.574%, and 1.100% respectively. For the second MACS, the proportions of CD90+ cells in the blank control group, experimental group, CD90– group, and CD90+ group was 0.032%, 0.961%, 0.426%, and 9.700% respectively. Conclusions The normal liver tissues do not express the CD90, but the liver cancer tissues express CD90 highly. There is a few CD90+ cells in Huh-7 and MHCC97-H liver cancer cell lines. The MACS has a certain effect on improving the proportion of CD90+ cells in the cell lines. The serum-free suspension culture has no effect on enriching CD90+ cells.
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.
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.
ObjectiveTo explore the effects of hypoxia inducible factor-1 alpha (HIF-1α) on the reverse differentiation of hepatocellular carcinoma cells into liver cancer stem cells, and the maintenance of malignant biological behavior in hypoxic environment.MethodsCD133-negative cells in HepG2 cells were separated by immunomagnetic beads and divided into two groups. The cells of siRNA group were transfected with siRNA-HIF-1α to silence the expression of HIF-1α gene, while cells of the blank control group did not transfect any siRNA fragments. The two groups of cells were cultured under normal and hypoxic conditions respectively. MTT, cloning and Transwell chamber experiments were used to detect the proliferation and invasion ability of cells. Western blot and real-time PCR (RT-PCR) were used to detect the expressions of HIF-1α, CD133, CD90, and CD44 protein and mRNA in cells.ResultsMTT results showed that the cell proliferation rate increased with the prolongation of hypoxia in four groups. Compared with the blank control group at 24, 32, 40, and 48 hours, the cell proliferation rate decreased significantly after siRNA-HIF-1a transfection, on both two kinds of cultured conditions (P<0.05). The results of plate cloning experiment showed that the number of cell-forming clones increased significantly after hypoxic culture (there were significant differences between the transfected normoxic group and transfected hypoxic group, blank control normoxic group and blank control hypoxic group, P<0.05); and the formation of transfected hypoxic condition group at the same time of hypoxia was also significant (P<0.05). The number of clones were significantly less than that of the blank control group at the hypoxic condition (P<0.05). Transwell lab experiment showed that after hypoxic culture, the number of cells migrated to the inferior chamber in the transfection group was significantly reduced compared with that of the blank control group (P<0.05). Western blot and RT-PCR results showed that the expression levels of HIF-1α protein and tumor stem cell markers (CD133, CD90, and CD44 protein) in the blank control hypoxic condition group were significantly higher than those in the other three groups (P<0.05); after siRNA-HIF-1a transfection, HIF-1α mRNA and tumor stem cell markers mRNA (CD133, CD90, and CD44 mRNA) in the transfected hypoxic condition group were significantly lower than those in the transfected normal condition group and the blank control normal condition group (P<0.05).ConclusionsIn hypoxia environment, HIF-1α can promote hepatocellular carcinoma cells to differentiate into liver cancer stem cells and enhance their malignant biological behavior.
ObjectiveTo explore the expression of genes related to hepatocellular carcinoma (HCC) stem cells and their prognostic correlation by using weighted gene co-expression network analysis (WGCNA).MethodsFirstly, the transcriptome sequencing (RNA-seq) and clinical data of HCC were downloaded from the public database the Cancer Genome Atlas (TCGA), and the mRNA expression-based stiffness index (mRNAsi) table of cancer stem cells was downloaded and sorted out to analyze the relationship between mRNAsi and pathological grade and prognosis of HCC. The mRNAsi of HCC was downloaded and the prognostic value of mRNAsi was discussed. Then we used WGCNA to screen the key modules related to liver cancer stem cells (LSCS). Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes were used for the functional and pathway enrichment analysis. The online database STRING was used to construct hub genes coding proteins interaction (PPI) network and screen key genes. Finally, the key genes were analyzed for expression differences and expression correlations. The online database Kaplan-Meier plotter was used for survival analysis and verified.ResultsmRNAsi was significantly upregulated in cancer tissues (P<0.001), and increased with the increase of pathological grade of HCC (P=0.001). The mortality rate of the higher mRNAsi group was higher than that of the lower mRNAsi group (P=0.006). GO analysis found that hub genes were mainly involved in biological processes, such as mitosis and DNA replication, and KEGG showed that hub genes were enriched in cell cycle, DNA mismatch repair, oocyte meiosis, and other signaling pathways. We screened 10 key genes (included CCNB1, CDC20, CDCA8, NDC80, KIF20A, TTK, CDC45, KIF15, MCM2, and NCAPG) related to mRNAsi of HCC based on WGCNA. The key genes were highly expressed in the tumor samples compared to the normal samples. In addition, there was a strong interaction between proteins of these key genes (P<0.05), a strong co-expression relationship at the transcriptional level, and all related to prognosis of HCC.ConclusionsmRNAsi plays an important role in the occurrence and development of HCC. Ten key genes related to LSCS were screened, which may act as therapeutic targets for inhibiting the stem cell characteristics of HCC.
ObjectiveTo investigate the most appropriate culture time with the action of EGF in colon cancer stem cells enrichment by suspension culture.MethodsDLD-1 cells were cultured in serum-free medium containing 20 ng/mL EGF to generate spheroid cells. The time gradient was set to 10 d, 20 d, 30 d and 40 d, the cell proportion of CD133+, CD44+ and CD133+CD44+ were confirmed by flow cytometery. The ability of self-renewal was detected by the sphere forming assay and the limited dilution assay, and the in vitro tumorigenicity of the cells was detected by the colony formation assay.ResultsIn the 30 d group, the proportion of CD133+ and CD133+ CD44+ cells were significantly higher than those in the other groups (allP<0.05), the CD44+ cell was higher than that in the 20 d group (P<0.05), but there was no significant difference with the other two groups (P>0.05). The results of the limited dilution assay and the colony formation assay, the number of spheres in the 30 d or 40 d group was the highest among the 4 groups, and there was no statistical difference between the 30 d group and 40 d group (P>0.05), with statistically significant difference between the 30 d, 10 d and 20 d groups (all P<0.05). The results of the sphere forming assay and the self-renewal ability of 30 d group was significantly higher compared with other groups (all P< 0.05).ConclusionThe cancer stem cells could be enriched more efficiently by suspension culture using 20 ng/mL EGF for 30 days.