Role of CD44 as cancer stem cell marker in triple-negative breast cancer and its association with histological grade and angiogenesis

Introduction: Cancer stem cells (CSC) within the tumors play a central role in tumorigenesis. It is, thus, of utmost importance to identify these cells to develop effective cancer therapy. Triple-Negative Breast Cancer (TNBC) is an aggressive molecular subtype of breast cancer associated with poor patient outcomes. The role of CD44 immunohistochemistry (IHC) as a putative CSC in breast carcinomas, particularly of the TNBC-subtype is ambiguous, with equivocal results. Aims and Objectives: The present study aims to assess the role of CSC in breast carcinoma by immunohistochemical analysis of CD44 expression in TNBC. The association of TNBC expressing CSC with histological grade as well as with angiogenesis (using CD34 IHC) has been studied. Materials and Methods: Biopsy samples from 58 patients with infiltrating ductal carcinoma, NST were studied. The histology of the tumor was sub-classified into grades 1–3. Based on immunohistochemical analysis (ER, PR, HER2/Neu), the cases were divided into TNBC and NTNBC groups. The tissue sections were also subjected to analysis for CD44 to identify the CSC-phenotype and CD34 to evaluate angiogenesis, to determine the microvascular density (MVD). Results: Out of the 58 cases in the study, 28 were TNBC and 30 were NTNBC. CSC phenotype (CD44 positive) was expressed significantly higher in the TNBC (78%) versus the NTNBC (53%) (p-value 0.043). The MVD estimated using CD34 IHC was lower in the TNBC group in our study, though the difference was not statistically significant. A larger proportion of cases in TNBC showed a higher histological grade (35%) in comparison to NTNBC (27%). However, statistically, it was not significant. Conclusion: Our study demonstrated that CD44 as a CSC marker is seen significantly more in the TNBC category of invasive ductal carcinomas. Further large-scale studies, to confirm these findings, will be of potential therapeutic and prognostic value.

Research Advances of RAD51AP1 in Tumor Progression and Drug Resistance / 中国肺癌杂志

The genomic instability may lead to an initiation of cancer in many organisms. Homologous recombination repair (HRR) is vital in maintaining cellular genomic stability. RAD51 associated protein 1 (RAD51AP1), which plays a crucial role in HRR and primarily participates in forming D-loop, was reported as an essential protein for maintaining cellular genomic stability. However, recent studies showed that RAD51AP1 was significantly overexpressed in various cancer types and correlated with poor prognosis. These results suggested that RAD51AP1 may play a significant pro-cancer effect in multiple cancers. The underlying mechanism is still unclear. Cancer stemness-maintaining effects of RAD51AP1 might be considered as the most reliable mechanism. Meanwhile, RAD51AP1 also promoted resistance to radiation therapy and chemotherapy in many cancers. Thus, researches focused on RAD51AP1, and its regulatory molecules may provide new targets for overcoming cancer progression and treatment resistance. Here, we reviewed the latest research on RAD51AP1 in cancers and summarized its differential expression and prognostic implications. In this review, we also outlined the potential mechanisms of its pro-cancer and drug resistance-promoting effects to provide several potential directions for further research.
.

Research progress of Chinese materia medica in inhibiting malignant biological behavior of lung cancer stem cells / 国际中医中药杂志

Chinese materia medica can inhibit the proliferation, invasion, migration and expression of drug-resistant proteins of lung cancer stem cells (LCSCs), and induce apoptosis and delay self-renewal, as well as exert anti-tumor effects by interfering with their ecological niche, immune microenvironment and aerobic glycolysis, etc. The biomarkers involved mainly include CD133, CD44, ALDH and ABCG2, while the related signaling pathways are Wnt/β-catenin, Hedgehog, and Notch. The research on the intervention of LCSCs by Traditional Chinese Medicine (TCM) is generally few, mostly concentrated in basic research, and the selected experimental indicators have a high repetition rate, involving fewer cell types and signaling pathways; there is a relative lack of clinical trials, which lack an organic connection with basic experiments. In the future, the quality of research is expected to be improved, and in-depth study of TCM with anti-lung cancer stem cell effect should be carried out, with the purpose to promote the precise treatment of lung cancer.

Possible role of ALDH1 and CD44 in lip carcinogenesis

Abstract Lip squamous cell carcinoma (LSCC) accounts for 12% of all head and neck cancers. It is caused by chronic exposure to ultraviolet light solar radiation and related to previous actinic cheilitis (AC). This study aimed to investigate the immunostaining of the putative cancer stem cells (CSC) markers ALDH1 and CD44 in AC (n=30) and LSCC (n=20). ALDH1 positivity was found to be statistically higher in LSCC than in AC lesions (p=0.0045), whilst CD44 expression was statistically higher in AC than in LSCC lesions (p=0.0155). ALDH1+ cells in AC lesions were associated with specific clinical features: a younger age (<60 years old), the female gender, white skin, not smoking or consuming alcohol, and a fast evolution, and not associated with the chronic exposure to UV radiation (p<0.0001). CD44 positivity was associated with patients who were male, feoderm, smoked, consumed alcohol, underwent occupational exposure to UV-radiation, and demonstrated lesions with log-time evolution (p<0.0001). ALDH1 + cells were associated with mild dysplasia using a system from the World Health Organization (WHO), and with a low risk of malignant transformation, according to the binary system (p<0.0001). CD44+ cells were also associated with moderated dysplasia, according to the WHO system. In LSCC, ALDH1 + cells were positively associated with patients who were older (≥ 60 years old), smokers, and with those who consumed alcohol (p<0.0001). CD44 + cells in LSCC were associated with older (≥ 60 years old) patients as well, but also with female patients, white skin, non-smokers, and individuals who did not consume alcohol (p<0.0001), all of whom showed distinct patterns in pre- and malignant lesions of both markers. Additionally, in LSCC, both ALDH1 and CD44 staining were associated with smaller tumor sizes (T1/T2; p<0.0001). In summary, although both ALDH1 and CD44 were associated with the presence of dysplasia in AC lesions, the present findings suggest that ALDH1 and CD44 may be activated by different etiopathogenic pathways, predominantly in distinct steps of oral carcinogenesis. CD44 would thus be more significantly related to the potentially malignant lesion, while ALDH1 would be closely linked to malignancy.

Role and Mechanism of Super-enhancers in Tumor Metastasis / 肿瘤防治研究

Super-enhancers (SEs) are large clusters of enhancers located near the promoter and are necessary to determine the identity of cancer cells. The alterations of super-enhancers can cause dysregulation of the transcriptional program, which resulted in tumor cells being addicted to certain transcriptional programs. Tumor metastasis is the leading cause of death in cancer. Recently, SEs have been demonstrated to facilitate tumor metastasis by regulating lncRNA generation, tumor microenvironment, epithelial-mesenchymal transition, and cancer stem cells. In this review, the characteristics of SEs, the relationship between SEs and tumor metastasis, and inhibitors against SEs are summarized to provide a reference for the relevant mechanism of SEs regulating tumor metastasis and provide new perspectives for the diagnosis and treatment of patients with cancer metastasis.

Deubiquitinating enzyme MINDY1 is an independent risk factor for the maintenance of stemness and poor prognosis in liver cancer cells / 中华肝脏病杂志

Objective: To explore the key deubiquitinating enzymes that maintain the stemness of liver cancer stem cells and provide new ideas for targeted liver cancer therapy. Methods: The high-throughput CRISPR screening technology was used to screen the deubiquitinating enzymes that maintain the stemness of liver cancer stem cells. RT-qPCR and Western blot were used to analyze gene expression levels. Stemness of liver cancer cells was detected by spheroid-formation and soft agar colony formation assays. Tumor growth in nude mice was detected by subcutaneous tumor-bearing experiments. Bioinformatics and clinical samples were examined for the clinical significance of target genes. Results: MINDY1 was highly expressed in liver cancer stem cells. The expression of stem markers, the self-renewal ability of cells, and the growth of transplanted tumors were significantly reduced and inhibited after knocking out MINDY1, and its mechanism of action may be related to the regulation of the Wnt signaling pathway. The expression level of MINDY1 was higher in liver cancer tissues than that in adjacent tumors, which was closely related to tumor progression, and its high expression was an independent risk factor for a poor prognosis of liver cancer. Conclusion: The deubiquitinating enzyme MINDY1 promotes stemness in liver cancer cells and is one of the independent predictors of poor prognosis in liver cancer.

Effects of Amarogentin on Residual Liver Cancer Stem Cells After Insufficient Thermal Ablation and Related Mechanism / 肿瘤防治研究

Objective To observe the effects of amarogentinon liver cancer stem cells (LCSCs) after insufficient thermal ablation and its mechanism. Methods A insufficient thermal ablation model of HepG2 cells was established by water bath method.The percentage of CD133-positive LCSCs and the mRNA and protein levels of CD133 were detected by flow cytometry, qRT-PCR and Western blot.The insufficient thermal ablation model of HepG2 cells was treated with variable doses of amarogentin for 24 h; the percentage of CD133-positive LCSCs, the proliferation and apoptosis of liver cancer cells, and the mRNA and protein levels of CD133, TBC1D15, and p53were detected by flow cytometry, qRT-PCR and Western blot. Results The percentage of CD133-positive HepG2 cells and the mRNA and protein levels of CD133 and TBC1D15in the insufficient thermal ablation model were significantly higher than those in the normal HepG2 cells.Amarogentin then markedly decreased the percentage of CD133-positive LCSCs, the proliferation rate of HepG2 cells, and the mRNA and protein levels of CD133 and TBC1D15 in the insufficient thermal ablationresidual model (all P < 0.05);inversely, the apoptosis rate of HepG2 cells and the phosphorylated levels of p53 in the insufficient thermal ablation model were significantly increased (all P < 0.05). Conclusion Amarogentin could reduce the proportion of LCSCs after insufficient thermal ablation, inhibit the proliferation, and promote the apoptosis of LCSCs, which maybe associated with increasing the phosphorylation of p53 and inhibiting the expression of TBC1D15.

Self-assembled multifunctional nanotheranostics against circulating tumor clusters in metastatic breast cancer

Circulating tumor clusters (CTC) disseminating from the primary tumor are responsible for secondary tumor formation where the conventional treatments such as chemotherapy and radiotherapy does not prevent the metastasis at locally advanced stage of breast cancer. In this study, a smart nanotheranostic system has been developed to track and eliminate the CTCs before it can colonize at a new site, which would reduce metastatic progression and increase the five-year survival rate of the breast cancer patients. Targeted multiresponsive (magnetic hyperthermia and pH) nanomicelles incorporated with NIR fluorescent superparamagnetic iron oxide nanoparticles were developed based on self-assembly for dual modal imaging and dual toxicity for spontaneous killing of CTCs in blood stream. A heterogenous tumor clusters model was developed to mimic the CTCs isolated from breast cancer patients. The nanotheranostic system was further evaluated for the targeting property, drug release kinetics, hyperthermia and cytotoxicity against developed CTC model in vitro. In vivo model in BALB/c mice equivalent to stage III and IV human metastatic breast cancer was developed to evaluate the biodistribution and therapeutic efficacy of micellar nanotheranostic system. Reduced CTCs in blood stream and low distant organ metastasis after treatment with the nanotheranostic system demonstrates its potential to capture and kill the CTCs that minimize the secondary tumor formation at distant sites.

EXPRESSION OF CD44 AS A CANCER STEM CELL MARKER IN ORAL CANCER: A META-ANALYSIS STUDY

Various researches have shown that Cluster of Differentiation 44 (CD44) is one of the valued markers. As it plays an important role in tumor growth and metastasis but studies also suggest it as a cancer stem cell (CSC) marker in oral cancer (OC). Therefore, we aimed to explore association between the expression of CD44 and clinicopathological characteristics along with the OC prognosis.We conducted literature search through PubMed database (till October 22, 2020) to determine and evaluate the clinical and prognostic significance of CD44 expression in OC patients. According to the inclusion criteria we finalized 9 studies with 867 OC cases. We found the positive expression of CD44 in advanced stages was prominently associated with reduced survival rate. Our analysis suggest that higher tumor expression of CD44 may predict poor survival in end staged OC patient

A short-term chick embryo in vivo xenograft model to study retinoblastoma cancer stem cells

Purpose: Cancer stem cells (CSCs) reported in various tumors play a crucial role in tumorigenesis and metastasis of retinoblastoma (Rb). Following the efforts to reduce, replace, and refine the use of mammalian models, we aimed to establish a short?term xenograft for Rb to evaluate the CSC properties of CD133? Rb Y79 cells, using the well?established chick embryo chorioallantoic membrane (CE?CAM) assay. Methods: Y79 cells were cultured, labeled with two different dyes (CM?Dil Y79 and enhanced green fluorescent protein (eGFP)) and sorted for CD133? and CD133 + subsets. Two million cells from each of the labeled groups were transplanted onto the abraded CAM on embryonic day 7 (E7). On E14, the tumor nodule formation on CAM and spontaneous metastasis to the embryos were evaluated by confocal microscopy, in vivo imaging, and histology. Results: Y79 cells formed pink–white raised perivascular nodules with feeder vessels on the CAM with both the types of labeled CD133? cells. CD133? cells, when compared to CD133 + cells, demonstrated significantly larger tumor volume (40.45 ± 7.744 mm3 vs 3.478 ± 0.69 mm3, P = 0.0014) and higher fluorescence intensity (CM?Dil: AUF = 6.37 × 107 ± 7.7 × 106 vs 1.08 × 107 ± 1.6 × 106; P < 0.0001; eGFP: AUF = 13.94 × 104 ± 2.54 × 104 vs AUF = 1.39 × 104 ± 0.4 × 104; P = 0.0003). The metastatic potential of CD133? cells was also observed to be higher as noted by in vivo imaging and histopathology. Conclusion: This study highlights that CE?CAM is a feasible alternative nonmammalian model for evaluating tumorigenicity and metastatic potential of Y79 CSCs. Increased tumorigenicity and metastatic potential of CD133? subset of tumor cells substantiate their CSC properties

Effect of Xuanfu Daizhe decoction on stemness of esophageal cancer cells / 中国应用生理学杂志

Objective: To investigate the effect of Xuanfu Daizhe decoction on the stemness of esophageal cancer cells. Methods: The BALB/c nude mice were randomly divided into the control group and experimental group, 5 mice in each group, which were continuously administered with normal saline and Xuanfu Daizhe decoction (9.89 g/kg) by gastrogavage, respectively. Human esophageal carcinoma cells ECA-109 (5×106) were subcutaneously injected into the mice on the 8th day. Tumor volume was measured twice a week. The mice were sacrificed 4 weeks after injection, and the tumor tissue and mouse serum were collected. The expressions of the major stemness-regulating transcription factors, i.e., NANOG, OCT4 and SOX2, were detected by RT-qPCR, Western Blot and immunohistochemistry. ECA-109 cells were treated with 10% fetal bovine serum and serum from the above two groups of mice for 48 hours respectively, and three replicate wells were set in each group, and the expressions of NANOG, OCT4, SOX2 and the levels of AKT and p-AKT were detected by RT-qPCR and Western Blot, respectively. ALDH activity in tumor cells was detected by flow cytometry; the number of spheroids of tumor cells was detected by the spheroidization experiment. Results: Compared with the control group, the growth and size of esophageal cancer tumors were significantly inhibited by Xuanfu Daizhe Decoction; the expressions of NANOG, OCT4, SOX2, the ALDH activity, the number of spheroids, and the levels of AKT and phosphorylated AKT (p-AKT) in esophageal cancer cells were significantly reduced by Xuanfu Daizhe Decoction both in vivo and in vitro. Conclusion: Xuanfu Daizhe Decoction inhibits the stemness of esophageal cancer cells, it may be a potentially effective drug for the treatment of esophageal cancer and provides a theoretical basis for the exploration of new effective drugs for the treatment of esophageal cancer.

Targeted killing of CD133+ lung cancer stem cells using paclitaxel-loaded PLGA-PEG nanoparticles with CD133 aptamers / 南方医科大学学报

OBJECTIVE@#To construct a polylactic acid-glycolic acid-polyethylene glycol (PLGA-PEG) nanocarrier (N-Pac-CD133) coupled with a CD133 nucleic acid aptamer carrying paclitaxel for eliminating lung cancer stem cells (CSCs).@*METHODS@#Paclitaxel-loaded N-Pac-CD133 was prepared using the emulsion/solvent evaporation method and characterized. CD133+ lung CSCs were separated by magnetic bead separation and identified for their biological behaviors and gene expression profile. The efficiency of paclitaxel-loaded N-Pac-CD133 for targeted killing of lung cancer cells was assessed in vitro. SCID mice were inoculated with A549 cells and received injections of normal saline, empty nanocarrier linked with CD133 aptamer (N-CD133), paclitaxel, paclitaxel-loaded nanocarrier (N-Pac) or paclitaxel-loaded N-Pac-CD133 (n=8, 5 mg/kg paclitaxel) on days 10, 15 and 20, and the tumor weight and body weight of the mice were measured on day 40.@*RESULTS@#Paclitaxel-loaded N-Pac-CD133 showed a particle size of about 100 nm with a high encapsulation efficiency (>80%) and drug loading rate (>8%), and was capable of sustained drug release within 48 h. The CD133+ cell population in lung cancer cells showed the characteristic features of lung CSCs, including faster growth rate (30 days, P=0.001) and high expressions of tumor stem cell markers OV6(P < 0.001), CD133 (P=0.001), OCT3/4 (P=0.002), EpCAM (P=0.04), NANOG (P=0.005) and CD44 (P=0.02). Compared with N-Pac and free paclitaxel, paclitaxel-loaded N-Pac-CD133 showed significantly enhanced targeting ability and cytotoxicity against lung CSCs in vitro (P < 0.001) and significantly reduced the formation of tumor spheres (P < 0.001). In the tumor-bearing mice, paclitaxel-loaded N-Pac-CD133 showed the strongest effects in reducing the tumor mass among all the treatments (P < 0.001).@*CONCLUSION@#CD133 aptamer can promote targeted delivery of paclitaxel to allow targeted killing of CD133+ lung CSCs. N-Pac-CD133 loaded with paclitaxel may provide an effective treatment for lung cancer by targeting the lung cancer stem cells.

Research progress in therapeutic resistance mechanism and therapeutic strategy of cancer stem cells / 国际生物医学工程杂志

Cancer stem cells (CSCs) are a class of cells with self-renewal, differentiation, and tumorigenic potential in tumors. It is currently believed that the resistance of CSCs to chemotherapy and radiotherapy is an important cause of tumor recurrence and metastasis. Researchers have found that related factors in many signaling pathways endow CSCs with the ability to adapt to changes in the microenvironment, including inflammatory factors, hypoxia, low pH, and a lack of nutrients. In recent years, the mechanism of CSCs' resistance to therapy has been studied, mainly including the drug efflux mediated by the ATP-binding cassette transporter, the effect of aldehyde dehydrogenase 1 (ALDH1) activity on tumor stem cells, the enhancement of DNA damage repair and degradation of reactive oxygen species, autophagy, activation of development-related pathways, stimulation of the microenvironment, and EMT. The targeting strategies for CSCs include targeting signaling pathway inhibitors, targeting multidrug resistance, DNA damage repair, ALDH, targeting the tumor microenvironment, immunotherapy, etc. In this review, the research progress in CSCs treatment resistance and related treatment strategies was reviewed.

Combination effect of doxorubicin and HIF inhibitor on MCF-7 CD44+/CD24- subpopulation cells in hypoxic condition

Abstract Hypoxia-inducible factors (HIFs) and cancer stem cells (CSCs) are two challenging causes of radiotherapy and chemotherapy resistance, leading to most cases of failure and recurrence in breast cancer therapy. This study was conducted to investigated the inhibitory effect of combination therapy with doxorubicin (an anthracycline) and FM19G11 (an HIF inhibitor) on MCF-7 cells and their CSC-like cells (CSC-LCs). MCF-7 CSC-LCs with a CD44+/CD24- phenotype were sorted and characterized by flow cytometry. A combination of doxorubicin and FM19G11 caused more cytotoxic effects on MCF-7 and CSC-LCs compared to doxorubicin monotherapy. The largest synergistic effect was observed in CSC-LCs under hypoxic conditions; however, MCF-7 cells showed no synergism in normoxic conditions. The administration of doxorubicin and FM19G11 induced late apoptotic and necrotic cell death in MCF-7 and CSC-LCs. Additionally, G2 phase arrest was observed in both cells. Our results demonstrated that co-administration of FM19G11 and doxorubicin had a synergistic effect in hypoxia and improved drug resistance in breast cancer stem cells.

Research advance in bone marrow metastasis in children′s neuroblastoma / 国际儿科学杂志

Neuroblastoma is the most common extracranial solid tumor for infants and young children.About 50% of patients have extensive metastasis before diagnosis, and the neuroblastoma can metastasize to bone marrow, bone, lymph node, orbit, liver and skin.Bone marrow is the most common site of neuroblastoma metastasis and recurrence.Once neuroblastoma metastasize or relapse, their survival rate will reduce significantly.The mechanism of neuroblastoma bone marrow metastasis has not been elucidated.The drug resistance of tumor cells, the interaction of bone marrow microenvironment, and the regulation of cell signaling pathways may play important roles in regulating tumor cell bone marrow metastasis.This review summarizes the research progress of bone marrow metastasis in neuroblastoma, which helps us to better understand the mechanism of interaction between neuroblastoma and the bone marrow microenvironment, and to provide new ideas for the diagnosis and treatment of patients.

Metabolism and immunity in breast cancer / 医学前沿

Breast cancer is one of the most common malignancies that seriously threaten women's health. In the process of the malignant transformation of breast cancer, metabolic reprogramming and immune evasion represent the two main fascinating characteristics of cancer and facilitate cancer cell proliferation. Breast cancer cells generate energy through increased glucose metabolism. Lipid metabolism contributes to biological signal pathways and forms cell membranes except energy generation. Amino acids act as basic protein units and metabolic regulators in supporting cell growth. For tumor-associated immunity, poor immunogenicity and heightened immunosuppression cause breast cancer cells to evade the host's immune system. For the past few years, the complex mechanisms of metabolic reprogramming and immune evasion are deeply investigated, and the genes involved in these processes are used as clinical therapeutic targets for breast cancer. Here, we review the recent findings related to abnormal metabolism and immune characteristics, regulatory mechanisms, their links, and relevant therapeutic strategies.

3D chromatin architecture and epigenetic regulation in cancer stem cells

Dedifferentiation of cell identity to a progenitor-like or stem cell-like state with increased cellular plasticity is frequently observed in cancer formation. During this process, a subpopulation of cells in tumours acquires a stem cell-like state partially resembling to naturally occurring pluripotent stem cells that are temporarily present during early embryogenesis. Such characteristics allow these cancer stem cells (CSCs) to give rise to the whole tumour with its entire cellular heterogeneity and thereby support metastases formation while being resistant to current cancer therapeutics. Cancer development and progression are demarcated by transcriptional dysregulation. In this article, we explore the epigenetic mechanisms shaping gene expression during tumorigenesis and cancer stem cell formation, with an emphasis on 3D chromatin architecture. Comparing the pluripotent stem cell state and epigenetic reprogramming to dedifferentiation in cellular transformation provides intriguing insight to chromatin dynamics. We suggest that the 3D chromatin architecture could be used as a target for re-sensitizing cancer stem cells to therapeutics.

FOXC1 Knockdown Reverses Gefitinib Resistance in Non-small Cell Lung Cancer / 中国肺癌杂志

BACKGROUND@#Lung cancer is the malignant tumor with the highest incidence and mortality in China, among which non-small cell lung cancer (NSCLC) accounts for about 80%. Epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) targeted therapy has been playing an important role in treatment of NSCLC. However, unavoidable therapeutic resistance significantly limits the clinical efficacy of EGFR-TKI. As a key member of the forkhead box protein family, FOXC1 is aberrantly expressed in NSCLC and involved in NSCLC progression. The aim of this work is to investigate the effect and potential mechanism of FOXC1 on gefitinib resistance in NSCLC.@*METHODS@#Western blot was performed to assess the expression of FOXC1 protein in HCC827/GR cells. Immunohistochemistry (IHC) assays were performed in human NSCLC tissues with gefitinib resistance. HCC827/GR cells were transfected with shRNA specifically targeting FOXC1 mRNA and stable cell lines were established. The effects of FOXC1 on cell viability and apoptosis were analyzed using a new methyl thiazolyl tetrazolium assay (MTS assay) and flow cytometry. Self-renewal ability was determined by mammosphere-formation analysis. Quantitative real-time PCR (qRT-PCR) and Western blot were employed to detect the expression of SOX2, Nanog, OCT4 and CD133. Flow cytometry analysis were further used to detect the level of CD133. IHC assays were used to detect the levels of SOX2 and CD133 in NSCLC tissues with genfitiinb resistance. Correlations of the expressions of FOXC1, CD133 and SOX2 with each other in lung adenocarcinoma samples were analyzed based on The Cancer Genome Atlas (TCGA) database.@*RESULTS@#The expression of FOXC1 is significantly increased in HCC827/GR cells compared with HCC827 cells (P<0.05). IHC results showed FOXC1 was highly expressed in NSCLC tissues with gefitinib resisitance. Knockdown of FOXC1 significantly increased the sensitivity of HCC827/GR cells to gefitinib. The cell viability was decreased and the apoptosis was promoted (P<0.05). Moreover, FOXC1 knockdown apparently inhibited the expression of SOX2 and CD133, and decreased the mammosphere-formation capacity in HCC827/GR cells. In NSCLC tissues with gefitinib resistance, the expressions of SOX2 and CD133 were significantly higher compared with gefitinib-sensitive tissues (P<0.01). Meanwhile, the expressions of FOXC1, CD133 and SOX2 with each other were positively correlated (P<0.05).@*CONCLUSIONS@#FOXC1 could increase gefitinib resitance in NSCLC, by which mechanism is related to the regulation of cancer stem cell properties.

Molecular markers and mechanisms for stemness maintenance of liver cancer stem cells: a review / 生物工程学报

Primary liver cancer (PLC) is an aggressive tumor and prone to metastasize and recur. According to pathological features, PLC are mainly categorized into hepatocellular carcinoma, intrahepatic cholangiocarcinoma, mixed hepatocellular cholangiocarcinoma, and fibrolamelic hepatocellular carcinoma, etc. At present, surgical resection, radiotherapy and chemotherapy are still the main treatments for PLC, but the specificities are poor and the clinical effects are limited with a 5-year overall survival rate of 18%. Liver cancer stem cells (LCSCs) are a specific cell subset existing in liver cancer tissues. They harbor the capabilities of self-renewal and strong tumorigenicity, driving tumor initiation, metastasis, drug resistance and recurrence of PLC. Therefore, the identification of molecular markers and the illustration of mechanisms for stemness maintenance of LCSCs can not only reveal the molecular mechanisms of PLC tumorigenesis, but also lay a theoretical foundation for the molecular classification, prognosis evaluation and targeted therapy of PLC. The latest research showed that the combination of 5-fluorouracil and CD13 inhibitors could inhibit the proliferation of CD13+ LCSCs, thereby reducing overall tumor burden. Taken together, LCSCs could be the promising therapeutic targets of PLC in the future. This review summarizes the latest progress in molecular markers, mechanisms for stemness maintenance and targeted therapies of LCSCs.

Trends in Research of Cancer Stem Cells: A Bibliometric Analysis Based on CiteSpace / 肿瘤防治研究

Objective To explore the research hotspots and trends in the field of CSCs through the bibliometric analysis of the literature on CSCs. Methods Based on the core database of Web of Science, CiteSpace was used to analyze the annual distribution of published articles, authors, institutions, countries, journals, citations and keywords, and to explore the frequency, centrality and clustering of key words. Results (1) A total of 8131 articles were included after screening. China was the country with the largest number of articles, and Sun Yat-Sen University was the organization with the largest number of articles; (2) The hot spots in the field of CSCs are the research of CSCs in breast cancer and pancreatic cancer, the research of CSCs sorting and identification of molecular markers ALDH and genes PTEN, Sox2, C-myc, EZH2, the mechanism of EMT inducing the production of CSCs and promoting tumor metastasis, cellular and molecular mechanisms of CSCs resistance to chemical, radiation and targeted drug attacks, Wnt/β-catenin signaling pathway and tumor microenvironment regulate the differentiation of CSCs and targeted inhibition of CSCs in the treatment of malignant tumors; (3) The research trend of CSCs is CSCs stem research-biological mechanism of CSCs-CSCs application in the treatment of cancer. Conclusion The focus and direction of CSCs research are EMT inducing CSCs to promote tumor metastasis, CSCs resisting chemical attack, mesenchymal stem cells regulating CSCs, the metabolism of CSCs, and inhibitors targeting CSCs at present and in the future.