• Retinoblastoma
• Wnt pathway
• cancer stem cells
• drug resistance
• targeted therapy
• tumor.

• Humans
• Retinoblastoma/pathology
• Retinoblastoma/therapy
• Neoplastic Stem Cells/pathology
• Drug Resistance, Neoplasm
• Animals
• Retinal Neoplasms/therapy
• Retinal Neoplasms/pathology

• 7222025 Natural Science Foundation of Beijing
• DFL20190201 Beijing Hospitals Authority'Ascent Plan
• 20220484218 Beijing Science and Technology Rising Star Program - Cross--cooperation project

• endometrial cancer
• cancer stem cells

Mesenchymal stem cells (MSCs) are critical in regenerating tissues because they can differentiate into various tissue cells. MSCs interact closely with cells in the tissue microenvironment during the repair of damaged tissue. Although regarded as non-healing wounds, tumors can be treated by MSCs, which showed satisfactory treatment outcomes in previous reports. However, it is largely unknown whether the biological behaviors of MSCs would be affected by the tumor microenvironment. Exploring the truth of tumor microenvironmental cues driving MSCs tumor “wound” regeneration would provide a deeper understanding of the biological behavior of MSCs. Therefore, we mimicked the tumor microenvironment using co-cultured glioma C6 cells and rat MSCs, aiming to assess the proliferation and migration of MSCs and the associated effects of Stat3 in this process. The results showed that co-cultured MSCs significantly exhibited enhanced tumorigenic, migratory, and proliferative abilities. Both up-regulation of Stat3 and down-regulation of miR-134-5p were detected in co-cultured MSCs. Furthermore, miR-134-5p directly regulated Stat3 by binding to the sequence complementary to microRNA response elements in the 3′-UTR of its mRNA. Functional studies showed that both the migration and proliferation abilities of co-cultured MSCs were inhibited by miR-134-5p, whereas Stat3 gain-of-function treatment reversed these effects. In addition, Pvt1 was confirmed to be regulated by miR-134-5p through Stat3 and the suppression of Pvt1 reduced the migration and proliferation abilities of co-cultured MSCs. To sum up, these results demonstrate a suppressive role of miR-134-5p in tumor-environment-driven malignant transformation of rat MSCs through directly targeting Stat3, highlighting a crucial role of loss-of-function of miR-134-5p/Stat3 axis in the malignant transformation, providing a reference to the potential clinic use of MSCs.

Cancer stem cells (CSCs) have been considered as a potential therapeutic target for cervical carcinoma. CD 276 is a well-known immune check point molecular, but its relationship with cervical CSCs was still unclear.

HeLa cell lines were obtained as cervical carcinoma in vitro model. HeLa cell Sphere formation culture was performed and CD276, OCT4 and SOX2 expression were determined by RT-qPCR. Transiently transfection and siRNA interference were used to modify CD276 expression. HeLa cell colony has been counted and cell proliferation was assessed by MTT assay. The relationship between CD276 and chemotherapy resistance of HeLa cell were evaluated by cisplatin treatment. Additionally, the mice model of xenograft tumor was established and CD276’s function was evaluated in vivo.

Here, we demonstrate that the expression of CD276 is positively correlated with the amount of sphere-forming cells in HeLa cell lines. Overexpression of CD276 causes the inhibition of HeLa cells’ sphere formation, colony formation and cell viability. Meanwhile, the downregulation of CD276 leads to the other way. We also demonstrate that CD276 contributes to the chemotherapy resistance in the cell line. Furthermore, we verify the CD276’s function on HeLa xenotransplantation mice model.

These results suggest that CD276 elevates the self-renewal capacity of HeLa CSCs.

• CD276
• HeLa cells
• cancer stem cells (CSCs)
• cervical carcinoma
• sphere formation cells

• BRD4
• EP300
• Epithelial ovarian cancer (EOC)
• KPNA4
• miR-596

• chronomere
• stem cells
• telomerase
• telomere
• theory of aging

• Aging/metabolism
• Humans
• Mitochondria/metabolism
• Telomerase/metabolism
• Telomere/metabolism
• Telomere Shortening

• Biomarkers, Tumor/genetics
• Breast Neoplasms/genetics
• Breast Neoplasms/pathology
• Cell Adhesion/drug effects
• Cell Adhesion/genetics
• Cell Movement/drug effects
• Cell Movement/genetics
• Cell Proliferation/drug effects
• Cell Proliferation/genetics
• Disease-Free Survival
• Epithelial-Mesenchymal Transition/drug effects
• Female
• Gene Expression Regulation, Neoplastic/drug effects
• Humans
• MCF-7 Cells
• Neoplasm Invasiveness/genetics
• Neoplasm Invasiveness/pathology
• Prognosis
• RNA, Double-Stranded/genetics
• RNA, Double-Stranded/pharmacology
• Tenascin/antagonists & inhibitors
• Tenascin/genetics

• Ministerstwo Nauki i Szkolnictwa Wyższego
• Narodowe Centrum Badań i Rozwoju

• Angiogenesis
• Conditioned medium
• FGF-2
• HUVECs
• Overexpression
• hGMSCs

• Animals
• Cell Movement
• Culture Media, Conditioned/analysis
• Fibroblast Growth Factor 2/metabolism
• Gingiva/cytology
• Human Umbilical Vein Endothelial Cells/metabolism
• Humans
• Mesenchymal Stem Cell Transplantation/methods
• Mesenchymal Stem Cells/metabolism
• Mice
• Mice, Inbred NOD
• Mice, SCID
• Neovascularization, Physiologic
• Transfection

• National Natural Science Foundation of China

• Drosophila
• ETO-1
• FLT3 ITD
• IDH1/2
• NPM-1
• Zebrafish
• mice
• rats

• Animals
• Carcinogens/toxicity
• Disease Models, Animal
• Drosophila melanogaster
• Leukemia, Myeloid, Acute/etiology
• Leukemia, Myeloid, Acute/pathology
• Mice
• Mutagenesis
• Oncogenic Viruses/pathogenicity
• Rats
• Zebrafish

• Cancer stem cells
• Healthy cells
• Mathematical models

Cancer stem cells (CSCs) are defined as a rare subpopulation of undifferentiated cells with biological characteristics that include the capacity for self-renewal, differentiation into various lineages, and tumor initiation. To explore the mechanism of CSCs in esophageal squamous cell carcinoma (ESCC), we focused on Leucine-rich repeat containing G protein-coupled receptor 5 (Lgr5), a target gene of the Wnt signaling pathway, which has been identified as a marker of intestinal stem cells and shown to be overexpressed in several human malignancies. Lgr5 expression was significantly correlated with lymph node metastasis, increased depth of invasion, increased tumor size, advanced differentiation, higher AJCC stage and poorer survival. Silencing of Lgr5 expression in the ESCC cell line KYSE450 by small interfering RNA (siRNA) strongly inhibited cell proliferation, migration and invasion ability, the expression of CSCs-related genes and Wnt/β-catenin signaling. In addition, Lgr5 was highly expressed in ESCC spheroid body cells, which were identified by high expression of CSCs-related genes, and high tumorigenicity in vivo. Taken together, these results demonstrate that Lgr5 activation of Wnt/β-catenin signaling is a potential mechanism to promote the progression of ESCC and ESCC stem cell renewal, and Lgr5 may be used as a molecular target for the development of treatments for ESCC.

• Lgr5
• cancer stem cells
• esophageal squamous cell carcinoma
• small interfering RNA
• spheroid body cells

• Exosome
• Extracellular vesicle
• Liver
• Mesenchymal stem cell
• Nanovesicle

• Animals
• Extracellular Vesicles
• Humans
• Liver Diseases/therapy

• Biomarkers, Tumor/metabolism
• Cell Separation/methods
• Humans
• Liver Neoplasms/pathology
• Liver Neoplasms/therapy
• Neoplastic Stem Cells/pathology
• Signal Transduction

• Cancer stem cells
• Mathematical models
• Normal cells

Gastric cancer (GC) is widely associated with chronic inflammation. The pro inflammatory microenvironment provides conditions that disrupt stem/progenitor cell proliferation and differentiation. The signal transducer and activator of transcrip- tion-3 (STAT3) signaling pathway is involved in inflammation and also contributes to the maintenance of embryonic stem cell (ESCs) pluripotency. Here, we have investi- gated the activation status of STAT3 in GC stem-like cells (GCSLCs).

In this experimental research, CSLCs derived from the human GC cell line MKN-45 and patient specimens, through spheroid body formation, character- ized and then assayed for the STAT3 transcription factor expression in mRNA and protein level further to its activation.

Spheroid cells showed higher potential for spheroid formation than the pa- rental cells. Furthemore, stemness genes NANOG, c-MYC and SOX-2 were over expressed in spheroids of MKN-45 and in patient samples. In MKN-45 spheroid cells, epithelial mesenchymal transition (EMT) related markers CDH2, SNAIL2, TWIST and VIMENTIN were upregulated (P<0.05), but we observed no change in expression of the E-cadherin epithelial marker. These cells exhibited more resistance to docetaxel (DTX) when compared with parental cells (P<0.05) according to the MTS assay. Al- though immunostaining and Western blotting showed expression of the STAT3 pro- tein in both spheroids and parents, the mRNA level of STAT3 in spheroids was higher than the parents. Nuclear translocation of STAT3 was accompanied by more intensive phospho-STAT3 (p-STAT3) in spheroid structures relative to the parent cells accord- ing to flow cytometry analysis (P<0.05).

The present findings point to STAT3 over activation in GCSLCs. Com- plementary experiments are required to extend the role of STAT3 in stemness fea- tures and invasion properties of GCSCs and to consider the STAT3 pathway for CSC targeted therapy.

• Cancer Stem Cells
• EMT
• Gastric Cancer
• STAT3
• Spheroid

Breast cancer stem cells (BCSCs) have been reported as the origin of breast cancer and the radical cause of drug resistance, relapse and metastasis in breast cancer. BCSCs could be derived from mutated mammary epithelial stem cells (MaSCs). Therefore, comparing the molecular differences between BCSCs and MaSCs may clarify the mechanism underlying breast carcinogenesis and the targets for gene therapy. Specifically, the distinct miRNome data of BCSCs and MaSCs need to be analyzed to find out the key miRNAs and reveal their roles in regulating the stemness of BCSCs.

MUC1⁻ESA⁺ cells were isolated from normal mammary epithelial cell line MCF-10A by fluorescence-activated cell sorting (FACS) and tested for stemness by clonogenic assay and multi-potential differentiation experiments. The miRNA profiles of MaSCs, BCSCs and breast cancer MCF-7 cells were compared to obtain the candidate miRNAs that may regulate breast tumorigenesis. An miRNA consecutively upregulated from MaSCs to BCSCs to MCF-7 cells, miR-200c, was chosen to determine its role in regulating the stemness of BCSCs and MaSCs in vitro and in vivo. Based on bioinformatics, the targets of miR-200c were validated by dual-luciferase report system, western blot and rescue experiments.

In a 2-D clonogenic assay, MUC1⁻ESA⁺ cells gave rise to multiple morphological colonies, including luminal colonies, myoepithelial colonies and mixed colonies. The clonogenic potential of MUC1⁻ESA⁺ (61.5 ± 3.87 %) was significantly higher than that of non-stem MCF-10A cells (53.5 ± 3.42 %) (P < 0.05). In a 3-D matrigel culture, MUC1⁻ESA⁺ cells grew into mammospheres with duct-like structures. A total of 12 miRNAs of interest were identified, 8 of which were upregulated and 4 downregulated in BCSCs compared with MaSCs. In gain- and lost-of-function assays, miR-200c was sufficient to inhibit the self-renewal of BCSCs and MaSCs in vitro and the growth of BCSCs in vivo. Furthermore, miR-200c negatively regulated programmed cell death 10 (PDCD10) in BCSCs and MaSCs. PDCD10 could rescue the tumorigenesis inhibited by miR-200c in BCSCs.

Accumulating evidence shows that there is a milignant transformation from MaSCs into BCSCs. The underlying mechanism remains unclear. In present study, miRNA profiles between MaSCs and BCSCs were obtained. Then miRNA-200c, downregulated in both MaSCs and BCSCs, were verified as anti-oncogene, and played essential role in regulating self-renewal of both kinds of stem-like cells. These findings reveal a novel insights of breast tumorigenesis.

PDCD10 is a target gene of miR-200c and also a possible mechanism by which miR-200c plays a role in regulating the stemness of BCSCs and MaSCs.

The online version of this article (doi:10.1186/s12885-015-1655-5) contains supplementary material, which is available to authorized users.

The objective of the present investigation was to study the clinical significances of the abnormal expressions of Piwil1 and Piwil2 protein in colonic adenoma and adenocarcinoma.

This study had applied immunohistochemical method to detect 45 cases of tissues adjacent to carcinoma (distance to cancerous tissue was above 5 cm), 41 cases of colonic adenoma and 92 cases of colon cancer tissues, and their Piwil1 and Piwil2 protein expression levels.

The correlation of both expression and its relationship with clinicopathological features of colon cancer was analyzed.

Positive expression rates of Piwil1 in tissues adjacent to carcinoma, colonic adenoma, and colon cancer were 11.1% (5/45), 53.7% (22/41), and 80.4% (74/92), respectively; the expression rates increased, and the comparisons between each two groups were statistically significant (P<0.05). In each group, the positive expression rates of Piwil2 were 24.4% (11/45 cases), 75.6% (31/41 cases), and 92.4% (85/92 cases); expression rates increased, and the comparisons between each two groups were statistically significant (P<0.05). Piwil1 expression and the correlation of the degree of differentiation, TNM stage, and lymph node metastasis were statistically significant (P<0.05). Piwil2 expression and the correlation of the degree of differentiation, tumor node metastasis (TNM) stage, and lymph node metastasis had no statistical significance (P>0.05). In colon cancer tissue, Piwil1 and Piwil2 expressions were positively correlated (r=0.262, P<0.05).

The results showed that the abnormal expression of Piwil1 and Piwil2 might play an important role in the process of colon cancer development.

• Piwil1
• Piwil2
• colon cancer
• colonic adenoma
• immunohistochemical

• Animals
• Apoptosis/drug effects
• Apoptosis/radiation effects
• Cell Proliferation/drug effects
• Cell Proliferation/radiation effects
• Culture Media, Conditioned/pharmacology
• Heme Oxygenase-1/metabolism
• Inflammation/etiology
• Inflammation/metabolism
• Inflammation Mediators/metabolism
• Insulin-Like Growth Factor I/pharmacology
• Interleukin-1beta/metabolism
• Intestinal Diseases/drug therapy
• Intestinal Diseases/mortality
• Intestinal Diseases/pathology
• Intestinal Mucosa/drug effects
• Intestinal Mucosa/metabolism
• Intestinal Mucosa/pathology
• Intestinal Mucosa/radiation effects
• Mesenchymal Stem Cells/drug effects
• Mesenchymal Stem Cells/metabolism
• Nitric Oxide/metabolism
• Paracrine Communication
• Radiation Dosage
• Radiation Injuries, Experimental/drug therapy
• Radiation Injuries, Experimental/mortality
• Radiation Injuries, Experimental/pathology
• Rats
• Regeneration/drug effects
• Stem Cells/drug effects
• Stem Cells/metabolism
• Tumor Necrosis Factor-alpha/metabolism

• cancer stem cell
• chromosomal aberration
• neurosphere
• orthotopic xenograft model

• Animals
• Biomarkers, Tumor
• Cell Separation
• Humans
• Mice
• Neoplasms/physiopathology
• Neoplastic Stem Cells

Tumorigenesis is often described as a result of accumulated mutations that lead to growth advantage and clonal expansion of mutated cells. There is evidence in the literature that cancer cells are influenced by the microenvironment. Our previous studies demonstrated that the mouse mammary gland is capable of redirecting mouse cells of non-mammary origins as well as Mouse Mammary Tumor Virus (MMTV)-neu transformed cells toward normal mammary epithelial cell fate during gland regeneration. Interestingly, the malignant phenotype of MMTV-neu transformed cells was suppressed during serial transplantation experiments. Here, we discuss our studies that demonstrated the potential of the regenerating mouse mammary gland to redirect cancer cells of different species into a functional tumor-free mammary epithelial cell progeny. Immunochemistry for human specific CD133, mitochondria, cytokeratins as well as milk proteins and FISH for human specific probe identified human epithelial cell progeny in ducts, lobules, and secretory acini. Fluorescent In Situ Hybridization (FISH) for human centromeric DNA and FACS analysis of propidium iodine staining excluded the possibility of mouse-human cell fusion. To our knowledge this is the first evidence that human cancer cells of embryonic or somatic origins respond to developmental signals generated by the mouse mammary gland microenvironment during gland regeneration in vivo.

The cancer stem cell theory hypothesizes that cancer stem cells (CSCs), which possess self-renewal and other stem cell properties, are regarded as the cause of tumor formation, recurrence and metastasis. The isolation and identification of CSCs could help to develop novel therapeutic strategies specifically targeting CSCs. In this study, we enriched gastric cancer stem cells through spheroid body formation by cultivating the human gastric cancer cell line MKN-45 in defined serum-free medium. The stemness characteristics of spheroid body-forming cells, including self-renewal, proliferation, chemoresistance, tumorigenicity of the MKN-45 spheroid body-forming cells were evaluated, and the expression levels of stemness genes and related proteins in the MKN-45 spheroid body-forming cells were assessed. Furthermore, immunofluorescence staining for the stem cell markers on spheroid body-forming cells was examined to evaluate the association between stemness factors (Oct4, Sox2, Nanog) and the proposed CSC marker CD44. Our data demonstrated that non-adherent spheroid body-forming cells from the gastric cancer cell line MKN-45 cultured in stem cell-conditioned medium possessed gastric CSC properties, such as persistent self-renewal, extensive proliferation, drug resistance, high tumorigenic capacity and overexpression of CSC-related genes and proteins (Oct4, Sox2, Nanog and CD44), compared with the parental cells. More importantly, CD44-positive cells co-expressing the pluripotency genes Oct4, Sox2 and Nanog may represent gastric CSCs. Further experiments using more refined selection criteria such as a combination of two or multiple markers would be useful to specifically identify and purify CSCs.

Breast cancer is the second leading cause of cancer deaths in the United States. At present, the etiology of breast cancer is unknown; however the possibility of a distinct cell of origin, i.e. a cancer stem cell, is a heavily investigated area of research. Influencing signals from the tissue niche are known to affect stem cells. Literature has shown that cancer cells lose their tumorigenic potential and display ‘normal’ behavior when placed into ‘normal’ ontogenic environments. Therefore, it may be the case that the tissue microenvironment is able to generate signals to redirect cancer cell fate. Previously, we showed that pluripotent human embryonal carcinoma cells could be redirected by the regenerating mammary gland microenvironment to contribute epithelial progeny for ‘normal’ gland development in-vivo. Here, we show that that human metastatic, non-metastatic, and metastasis-suppressed breast cancer cells proliferate and contribute to normal mammary gland development in-vivo without tumor formation. Immunochemistry for human-specific mitochondria, keratin 8 and 14, as well as human-specific milk proteins (alpha-lactalbumin, impregnated transplant hosts) confirmed the presence of human cell progeny. Features consistent with normal mammary gland development as seen in intact hosts (duct, lumen formation, development of secretory acini) were recapitulated in both primary and secondary outgrowths from chimeric implants. These results suggest the dominance of the tissue microenvironment over cancer cell fate. This work demonstrates that cultured human breast cancer cells (metastatic and non-metastatic) respond developmentally to signals generated by the mouse mammary gland microenvironment during gland regeneration in-vivo.

• Breast Neoplasms/classification
• Breast Neoplasms/mortality
• Breast Neoplasms/pathology
• Cell Culture Techniques
• Cell Separation
• Cell Transformation, Neoplastic
• Epithelial Cells/classification
• Female
• Humans
• Neoplastic Stem Cells/physiology
• Stem Cells/physiology
• Telomerase/genetics

• R01CA105489 NCI NIH HHS
• R01CA116552 NCI NIH HHS
• R01 CA096844 NCI NIH HHS
• R01CA096844 NCI NIH HHS
• R01CA144027 NCI NIH HHS
• R01 CA099163 NCI NIH HHS
• R01 CA087986 NCI NIH HHS
• R01CA099163 NCI NIH HHS
• R01CA087986 NCI NIH HHS
• R01 CA116552 NCI NIH HHS
• R01 CA144027 NCI NIH HHS
• R01 CA105489 NCI NIH HHS

Acquiring abundant and high-purity cancer stem cells (CSCs) is an important prerequisite for CSC research. At present, researchers usually gain high-purity CSCs through flow cytometry sorting and expand them by short-term sphere culture. However, it is still uncertain whether we can amplify high-purity CSCs through long-term sphere culture. We have proposed a mathematical model using ordinary differential equations to derive the continuous variation of the CSC ratio in long-term sphere culture and estimated the model parameters based on a long-term sphere culture of MCF-7 stem cells. We found that the CSC ratio in long-term sphere culture presented as gradually decreased drift and might be stable at a lower level. Furthermore, we found that fitted model parameters could explain the main growth pattern of CSCs and differentiated cancer cells in long-term sphere culture.