Clinicopathological significance of CD133 in lung cancer: A meta-analysis

Clinical importance of serum and pleural fluid prominin-1 and hypoxia-inducible factor-1α concentration in the evaluation of lymph node involvement in patients with malignant pleural effusion

Introduction

Malignant pleural effusion (MPE) and lymph node metastasis (LNM) presence are poor prognostic factors that have importance for cancer patients. The study objective was to determine whether hypoxia-inducible factor-1α (HIF-1α) and prominin-1 (CD133) in pleural fluid (P) and serum (S) could be used as biomarkers for diagnosis of lymph node involvement in patients with MPE.

Materials and methods

Fifty-six patients with MPE and 30 healthy control subjects were included. Computerized tomography (CT) and positron emission tomography (PET) were used to diagnose pleural effusion. Patients with malignant cells in pleural fluid cytological examination were included in the MPE group. Thirty-five patients with lymph node metastases on CT were included in the LNM-positive MPE group. Serum and pleural fluid HIF-1α and CD-133 concentrations were measured manually via enzyme-linked immunosorbent assay (ELISA).

Results

Serum concentrations of HIF-1α and CD133 were higher in MPE patients. It was found that CD133/HIF-1α (S) ratio was higher in the malignant patient group with positive lymph node involvement than in the negative group, while concentrations of HIF-1α (P) were lower. Pleural fluid HIF-1α and CD133/HIF-1α (S) ratio had sufficient performance in diagnosing lymphatic metastases in patients with MPE (AUC = 0.90 and 0.83, respectively).

Conclusions

In conclusion, serum HIF-1α and CD133 concentrations were higher in patients with MPE, consistent with our hypothesis. Concentrations of HIF-1α (P) and CD133/HIF-1α (S) ratio can be used as biomarkers in diagnosing lymph node involvement in MPE patients, according to this experiment.

MPZL1 suppresses the cancer stem-like properties of lung cancer through β-catenin/TCF4 signaling

This study was designed to explore the influence of myelin protein zero-like protein 1 (MPZL1) on the stem-like properties of cancer cells and the underlying mechanism in lung adenocarcinoma. Real-time quantitative polymerase chain reaction (RT-qPCR) was utilized to evaluate mRNA expression level. CCK8, wound healing, and transwell assays were applied to assess cell proliferation, migration, and invasion. Tumorsphere-formation assay was utilized to assess cancer stem cell-like properties. LF3 was used to block the β-catenin/Transcription factor 4 (TCF-4) signaling. Xenograft nude mouse model was conducted; tumor weight and volume were recorded. Western blot assay was utilized to detect the expression levels of CD44, CD133, β-catenin, TCF-4, and MPZL1. Following MPZL1 knockdown, the mRNA expression levels of MPZL1, β-catenin, and TCF-4 were inhibited, while the mRNA expression levels of the above genes were increased after the MPZL1 overexpression. MPZL1 knockdown suppressed cell proliferation, migration, and invasion, reduced the tumorsphere-formation capacity, and restrained the expression levels of CD44 and CD133. However, MPZL1 overexpression promoted the cell proliferation, migration, and invasion, enhanced the tumorsphere-formation capacity, and increased the expression levels of CD44 and CD133. Interestingly, LF3 treatment partially revised the effect of MPZL1 overexpression. These findings were further corroborated by in vivo experiments. We concluded that MPZL1 could suppress the lung adenocarcinoma cells' proliferation, migration, invasion, and lung cancer stem cells characteristics. The underlying mechanism is involved in the activation of β-catenin/TCF-4 signaling.

Structural modification of resveratrol analogue exhibits anticancer activity against lung cancer stem cells via suppression of Akt signaling pathway

BACKGROUND

Compound with cancer stem cell (CSC)-suppressing activity is promising for the improvement of lung cancer clinical outcomes. Toward this goal, we discovered the CSC-targeting activity of resveratrol (RES) analog moscatilin (MOS). With slight structural modification from RES, MOS shows dominant cytotoxicity and CSC-suppressive effect.

METHODS

Three human lung cancer cell lines, namely H23, H292, and A549, were used to compare the effects of RES and MOS. Cell viability and apoptosis were determined by the MTT assay and Hoechst33342/PI double staining. Anti-proliferative activity was determined by colony formation assay and cell cycle analysis. Intracellular reactive oxygen species (ROS) were measured by fluorescence microscopy using DCFH₂-DA staining. CSC-rich populations of A549 cells were generated, and CSC markers, and Akt signaling were determined by Western blot analysis and immunofluorescence. Molecular docking and molecular dynamics (MD) simulations were used to predict the possible binding of the compound to Akt protein.

RESULTS

In this study, we evaluated the effects of RES and MOS on lung cancer and its anti-CSC potential. Compared with RES, its analog MOS more effectively inhibited cell viability, colony formation, and induced apoptosis in all lung cancer cell lines (H23, H292, and A549). We further investigated the anti-CSC effects on A549 CSC-rich populations and cancer adherent cells (A549 and H23). MOS possesses the ability to suppress CSC-like phenotype of lung cancer cells more potent than RES. Both MOS and RES repressed lung CSCs by inhibiting the viability, proliferation, and lung CSC-related marker CD133. However, only MOS inhibits the CSC marker CD133 in both CSC-rich population and adherent cells. Mechanistically, MOS exerted its anti-CSC effects by inhibiting Akt and consequently restored the activation of glycogen synthase kinase 3β (GSK-3β) and decreased the pluripotent transcription factors (Sox2 and c-Myc). Thus, MOS inhibits CSC-like properties through the repression of the Akt/GSK-3β/c-Myc pathway. Moreover, the superior inhibitory effects of MOS compared to RES were associated with the improved activation of various mechanism, such as cell cycle arrest at G2/M phase, production of ROS-mediated apoptosis, and inhibition of Akt activation. Notably, the computational analysis confirmed the strong interaction between MOS and Akt protein. MD simulations revealed that the binding between MOS and Akt1 was more stable than RES, with MM/GBSA binding free energy of - 32.8245 kcal/mol at its allosteric site. In addition, MOS interacts with Trp80 and Tyr272, which was a key residue in allosteric inhibitor binding and can potentially alter Akt activity.

CONCLUSIONS

Knowledge about the effect of MOS as a CSC-targeting compound and its interaction with Akt is important for the development of drugs for the treatment of CSC-driven cancer including lung cancer.

Aptamers as Smart Ligands for Targeted Drug Delivery in Cancer Therapy

Undesirable side effects and multidrug tolerance are the main holdbacks to the treatment of cancer in conventional chemotherapy. Fortunately, targeted drug delivery can improve the enrichment of drugs at the target site and reduce toxicity to normal tissues and cells. A targeted drug delivery system is usually composed of a nanocarrier and a targeting component. The targeting component is called a "ligand". Aptamers have high target affinity and specificity, which are identified as attractive and promising ligands. Therefore, aptamers have potential application in the development of smart targeting systems. For instance, aptamers are able to efficiently recognize tumor markers such as nucleolin, mucin, and epidermal growth factor receptor (EGFR). Besides, aptamers can also identify glycoproteins on the surface of tumor cells. Thus, the aptamer-mediated targeted drug delivery system has received extensive attention in the application of cancer therapy. This article reviews the application of aptamers as smart ligands for targeted drug delivery in cancer therapy. Special interest is focused on aptamers as smart ligands, aptamer-conjugated nanocarriers, aptamer targeting strategy for tumor microenvironment (TME), and aptamers that are specified to crucial cancer biomarkers for targeted drug delivery.

Nucleolin Overexpression Predicts Patient Prognosis While Providing a Framework for Targeted Therapeutic Intervention in Lung Cancer

Simple Summary

Despite the clinical benefit of new anticancer therapies, such as immune checkpoint inhibitors, lung cancer remains the most frequent cause of cancer-related death worldwide, thus supporting the need to develop novel anticancer treatments. Endothelial cells of the tumor-associated vasculature are easily accessible to drugs administered intravenously, besides having greater genetic stability than neoplastic cells and thus lowering the risk of developing drug resistance. In this respect, the identification of alternative targets, and therapeutic strategies, within the tumor vasculature is of high relevance. Accordingly, this work aimed at characterizing nucleolin expression in patient-derived pulmonary carcinomas and further validating nucleolin as a novel target to mediate successful therapeutic interventions against human lung cancers. The highlighted prognostic value of nucleolin points towards the applicability of nucleolin-based targeting strategies against nucleolin^high pulmonary carcinomas, present in every disease stage, in a clinical trial setting.

Abstract

Notwithstanding the advances in the treatment of lung cancer with immune checkpoint inhibitors, the high percentage of non-responders supports the development of novel anticancer treatments. Herein, the expression of the onco-target nucleolin in patient-derived pulmonary carcinomas was characterized, along with the assessment of its potential as a therapeutic target. The clinical prognostic value of nucleolin for human pulmonary carcinomas was evaluated through data mining from the Cancer Genome Atlas project and immunohistochemical detection in human samples. Cell surface expression of nucleolin was evaluated by flow cytometry and subcellular fraction Western blotting in lung cancer cell lines. Nucleolin mRNA overexpression correlated with poor overall survival of lung adenocarcinoma cancer patients and further predicted the disease progression of both lung adenocarcinoma and squamous carcinoma. Furthermore, a third of the cases presented extra-nuclear expression, contrasting with the nucleolar pattern in non-malignant tissues. A two- to twelve-fold improvement in cytotoxicity, subsequent to internalization into the lung cancer cell lines of doxorubicin-loaded liposomes functionalized by the nucleolin-binding F3 peptide, was correlated with the nucleolin cell surface levels and the corresponding extent of cell binding. Overall, the results suggested nucleolin overexpression as a poor prognosis predictor and thus a target for therapeutic intervention in lung cancer.

[Protein CD133 as a tumor stem cell marker]

The CD133 protein is a large transmembrane glycoprotein. Despite multiple studies, the role of CD133 protein in cells is still poorly understood. Nevertheless, there is an association of CD133 protein with neoplastic transformation. This review summarizes data on CD133 protein, its structure, regulation of expression, molecular interactions and representation in cells that have undergone malignant transformation. Available data suggest that CD133 may have a great potential for predicting survival in various solid tumors. This protein can also be a marker of glioma.

Jorunnamycin A Suppresses Stem-Like Phenotypes and Sensitizes Cisplatin-Induced Apoptosis in Cancer Stem-Like Cell-Enriched Spheroids of Human Lung Cancer Cells

It has been recognized that cancer stem-like cells (CSCs) in tumor tissue crucially contribute to therapeutic failure, resulting in a high mortality rate in lung cancer patients. Due to their stem-like features of self-renewal and tumor formation, CSCs can lead to drug resistance and tumor recurrence. Herein, the suppressive effect of jorunnamycin A, a bistetrahydroisoquinolinequinone isolated from Thai blue sponge Xestospongia sp., on cancer spheroid initiation and self-renewal in the CSCs of human lung cancer cells is revealed. The depletion of stemness transcription factors, including Nanog, Oct-4, and Sox2 in the lung CSC-enriched population treated with jorunnamycin A (0.5 μM), resulted from the activation of GSK-3β and the consequent downregulation of β-catenin. Interestingly, pretreatment with jorunnamycin A at 0.5 μM for 24 h considerably sensitized lung CSCs to cisplatin-induced apoptosis, as evidenced by upregulated p53 and decreased Bcl-2 in jorunnamycin A-pretreated CSC-enriched spheroids. Moreover, the combination treatment of jorunnamycin A (0.5 μM) and cisplatin (25 μM) also diminished CD133-overexpresssing cells presented in CSC-enriched spheroids. Thus, evidence on the regulatory functions of jorunnamycin A may facilitate the development of this marine-derived compound as a novel chemotherapy agent that targets CSCs in lung cancer treatment.

Novel Primary Human Cancer Stem-Like Cell Populations from Non-Small Cell Lung Cancer: Inhibition of Cell Survival by Targeting NF-κB and MYC Signaling

There is growing evidence that cancer stem cells (CSCs), a small subpopulation of self-renewal cancer cells, are responsible for tumor growth, treatment resistance, and cancer relapse and are thus of enormous clinical interest. Here, we aimed to isolate new CSC-like cells derived from human primary non-small cell lung cancer (NSCLC) specimens and to analyze the influence of different inhibitors of NF-κB and MYC signaling on cell survival. CSC-like cells were established from three squamous cell carcinomas (SCC) and three adenocarcinomas (AC) of the lung and were shown to express common CSC markers such as Prominin-1, CD44-antigen, and Nestin. Further, cells gave rise to spherical cancer organoids. Inhibition of MYC and NF-κB signaling using KJ-Pyr-9, dexamethasone, and pyrrolidinedithiocarbamate resulted in significant reductions in cell survival for SCC- and AC-derived cells. However, inhibition of the protein–protein interaction of MYC/NMYC proto-oncogenes with Myc-associated factor X (MAX) using KJ-Pyr-9 revealed the most promising survival-decreasing effects. Next to the establishment of six novel in vitro models for studying NSCLC-derived CSC-like populations, the presented investigations might provide new insights into potential novel therapies targeting NF-κB/MYC to improve clinical outcomes in NSCLC patients. Nevertheless, the full picture of downstream signaling still remains elusive.

Nanopore Sequencing Reveals Global Transcriptome Signatures of Mitochondrial and Ribosomal Gene Expressions in Various Human Cancer Stem-like Cell Populations

Simple Summary

Cancer is the leading cause of death in the industrialized world. In particular, so-called cancer stem cells (CSCs) play a crucial role in disease progression, as they are known to contribute to tumor growth and metastasis. Thus, CSCs are heavily investigated in a broad range of cancers. Nevertheless, global transcriptomic profiling of CSC populations derived from different tumor types is rare. We established three CSC populations from tumors in the uterus, brain, lung, and prostate and assessed their global transcriptomes using nanopore full-length cDNA sequencing, a new technique to assess insights into global gene profile. We observed common expression in all CSCs for distinct genes encoding proteins for organelles, such as ribosomes, mitochondria, and proteasomes. Additionally, we detected high expressions of inflammation- and immunity-related genes. Conclusively, we observed high similarities between all CSCs independent of their tumor of origin, which may build the basis for identifying novel therapeutic strategies targeting CSCs.

Abstract

Cancer stem cells (CSCs) are crucial mediators of tumor growth, metastasis, therapy resistance, and recurrence in a broad variety of human cancers. Although their biology is increasingly investigated within the distinct types of cancer, direct comparisons of CSCs from different tumor types allowing comprehensive mechanistic insights are rarely assessed. In the present study, we isolated CSCs from endometrioid carcinomas, glioblastoma multiforme as well as adenocarcinomas of lung and prostate and assessed their global transcriptomes using full-length cDNA nanopore sequencing. Despite the expression of common CSC markers, principal component analysis showed a distinct separation of the CSC populations into three clusters independent of the specific type of tumor. However, GO-term and KEGG pathway enrichment analysis revealed upregulated genes related to ribosomal biosynthesis, the mitochondrion, oxidative phosphorylation, and glycolytic pathways, as well as the proteasome, suggesting a great extent of metabolic flexibility in CSCs. Interestingly, the GO term “NF-kB binding” was likewise found to be elevated in all investigated CSC populations. In summary, we here provide evidence for high global transcriptional similarities between CSCs from various tumors, which particularly share upregulated gene expression associated with mitochondrial and ribosomal activity. Our findings may build the basis for identifying novel therapeutic strategies targeting CSCs.

Silencing of MicroRNA-503 in Rat Mesenchymal Stem Cells Exerts Potent Antitumorigenic Effects in Lung Cancer Cells

Purpose

Mesenchymal stem cells (MSCs) are largely studied for their potential clinical use. Recently, there has been gained further interest in the relationship between MSCs and tumorigenesis. MSCs are reported to both promote and abrogate tumor growth. The present study was designed to investigate whether miRNAs are involved in the interactions between MSCs and tumor cells in the tumor microenvironment.

Materials and Methods

Rat bone marrow-derived MSCs (rMSCs) were cultured with or without tumor-conditioned medium (TCM) to observe the effect upon MSCs by TCM. Microarrays and real-time PCR were performed between the two groups. A series of experiments were used to reveal the functional significance of microRNA-503 (miR-503) in rMSCs. Furthermore, the antitumorigenic effect of silencing of miR-503 in rMSCs (miR-503-i-rMSCs) in vivo was measured.

Results

We found that rMSCs in vitro exhibited tumor-promoting properties in TCM, and the microRNA profiles of rMSCs were significantly altered in TCM. However, miR-503-i-rMSCs can decrease the angiogenesis and growth of A549 cells. We also demonstrated in an in vivo tumor model that miR-503-i-rMSCs inhibited A549 tumor angiogenesis and significantly abrogated tumor initiation and growth. CD133 assays in peripheral blood and A549 xenografts further validated that miR-503-i-rMSCs, rather than rMSCs, exerted an antitumorigenic action in the A549 tumor model.

Conclusion

Our results suggest that miR-503-i-rMSCs are capable of tumor suppression. Further studies are required to develop clinical therapies based on the inhibition of the tumor-promoting properties and potentiation of the anti-tumor properties of MSCs.

Characterization of sphere cells derived from a patient-derived xenograft model of lung adenocarcinoma treated with ionizing radiation

PURPOSE

Cancer stem cells (CSCs) are relatively resistant to radiation compared to their non-tumorigenic progeny. Ionizing radiation (IR) can expand the pool of CSCs that leads to more aggressive cancers, but the reason underlying CSC-induced cancer aggressiveness after radiation therapy remains unclear. To understand this, we investigated the phenotypic and molecular characteristics of sphere cells formed from IR-treated patient-derived xenograft (PDX) lung adenocarcinoma tumors.

MATERIALS AND METHODS

After treatment with various modes of IR, we collected tumors from PDX mice and successfully obtained sphere cells. To compare tumorigenicity, we performed migration, invasion, and mouse transplantation assays with sphere cells from each group. To investigate the molecular features, we used a cDNA microarray and compared gene expression among groups.

RESULTS AND CONCLUSIONS

Tumorigenicity assays revealed that sphere cells from 2- or 5-Gy IR-treated tumors more aggressive than sphere cells from non-IR treated tumors. Microarray results showed that SERPIB4 and CCL2 were upregulated in sphere cells from IR-treated tumors compared to that in sphere cells from non-IR treated tumors. Interestingly, these genes are related to immune reactions in cancer. Taken together, our results suggest that the aggressiveness of sphere cells obtained after IR treatment is related to resistance, and provide new opportunities for exploring targeted therapies to overcome common radioresistance.

Non-Coding RNAs in Lung Tumor Initiation and Progression

Lung cancer is one of the deadliest forms of cancer affecting society today. Non-coding RNAs, such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), through the transcriptional, post-transcriptional, and epigenetic changes they impose, have been found to be dysregulated to affect lung cancer tumorigenesis and metastasis. This review will briefly summarize hallmarks involved in lung cancer initiation and progression. For initiation, these hallmarks include tumor initiating cells, immortalization, activation of oncogenes and inactivation of tumor suppressors. Hallmarks involved in lung cancer progression include metastasis and drug tolerance and resistance. The targeting of these hallmarks with non-coding RNAs can affect vital metabolic and cell signaling pathways, which as a result can potentially have a role in cancerous and pathological processes. By further understanding non-coding RNAs, researchers can work towards diagnoses and treatments to improve early detection and clinical response.

Mesenchymal Stem Cell Expressing TRAIL as Targeted Therapy against Sensitised Tumour

Tapping into the ability of engineered mesenchymal stem cells (MSCs) to mobilise into the tumour has expanded the scope of cancer treatment. Engineered MSCs expressing tumour necrosis factor (TNF)-related apoptosis inducing ligand (MSC-TRAIL) could serve as a platform for an efficient and targeted form of therapy. However, the presence of cancer stem cells (CSCs) that are resistant to TRAIL and apoptosis may represent a challenge for effective treatment. Nonetheless, with the discovery of small molecular inhibitors that could target CSCs and tumour signalling pathways, a higher efficacy of MSC-TRAIL mediated tumour inhibition can be achieved. This might pave the way for a more effective form of combined therapy, which leads to a better treatment outcome. In this review, we first discuss the tumour-homing capacity of MSCs, its effect in tumour tropism, the different approach behind genetically-engineered MSCs, and the efficacy and safety of each agent delivered by these MSCs. Then, we focus on how sensitisation of CSCs and tumours using small molecular inhibitors can increase the effect of these cells to either TRAIL or MSC-TRAIL mediated inhibition. In the conclusion, we address a few questions and safety concerns regarding the utilization of engineered MSCs for future treatment in patients.

The role of cancer stem cells in tumor heterogeneity and resistance to therapy

Cancer is a heterogenous disease displaying marked inter- and intra-tumoral diversity. The existence of cancer stem cells (CSCs) has been experimentally demonstrated in a number of cancer types as a subpopulation of tumor cells that drives the tumorigenic and metastatic properties of the entire cancer. Thus, eradication of the CSC population is critical for the complete ablation of a tumor. This is, however, confounded by the inherent resistance of CSCs to standard anticancer therapies, eventually leading to the outgrowth of resistant tumor cells and relapse in patients. The cellular mechanisms of therapy resistance in CSCs are ascribed to several factors including a state of quiescence, an enhanced DNA damage response and active repair mechanisms, up-regulated expression of drug efflux transporters, as well as the activation of pro-survival signaling pathways and inactivation of apoptotic signaling. Understanding the mechanisms underlying the acquisition of resistance to therapy may hold the key to targeting the CSC population.

Wnt signaling as potential therapeutic target in lung cancer

INTRODUCTION

Wingless-type (Wnt) signaling is tightly regulated at multiple cellular levels and is dysregulated in lung cancer. Therefore, it offers therapeutic targets for developing novel agents for lung cancer treatment.

AREAS COVERED

In this article, we discuss the role of the Wnt signaling pathway in lung cancer, highlighting the aberrant activation of Wnt in lung cancer stem cells and its implication in resistance to radiotherapy, chemotherapy and targeted therapy. We also expound the regulatory roles of microRNAs in Wnt signaling, as well as the potential of the Wnt pathway to provide biomarkers and therapeutic targets in lung cancer. The potential use of small molecule and biological inhibitors targeting the Wnt pathway for lung cancer therapy and prevention is also discussed.

EXPERT OPINION

Wnt signaling plays an important role in the development and metastasis of lung cancer; the pathway provides targets to develop agents towards for cancer prevention and therapy. A number of clinical trials have shown the effectiveness of Wnt pathway inhibitors in epithelial tumors. However, the side effects should be considered. Nevertheless, the results from clinical studies suggest that inhibitors targeting the Wnt signaling show promise against lung cancer.

Effect of CXCR4 and CD133 co-expression on the prognosis of patients with stage II~III colon cancer

BACKGROUND

To explore the relationship between CXCR4, CD133 co-expression and clinicopathological features as well as prognosis of patients with phase II~III colon cancer.

MATERIALS AND METHODS

Forty-nine paraffin-embedded samples of tumor tissue and epithelial tissue adjacent to cancer were collected from patients with colon cancer undergoing radical surgery in Baotou Cancer Hospital from January, 2010 to June, 2011. CXCR4 and CD133 expression was detected using immunohistochemistry and its relationship with clinicopathological features and the 3-year survival rate was analyzed.

RESULTS

In the tumor tissue and colonic epithelial tissue adjacent to cancer, the positive expression rates of CXCR4 were respectively 61.2% (30/49) and 8.16% (4/49), while those of CD133 being 36.7% (18/49) and 6.12% (3/49). CXCR4 and CD133 expression in tumor tissue was not related to patient age, gender, primary focal sites, tumor size, TNM staging, histological type, tumor infiltration depth and presence or absence of lymphatic metastasis, but CXCR4 and CD133 co-expression was associated with TNM staging and lymphatic metastasis. The 3-year survival rate of patients with CXCR4 and CD133 co-expression was 27.3% (3/11), and that of the remainderwas 76.3% (29/38), the difference being significant (χ2=7.0206, p=0.0081).

CONCLUSIONS

CXCR4 and CD133 co-expression may be a risk factor for poor prognosis of patients with stage II~III colon cancer.

Pluripotency transcription factors in lung cancer-a review

Lung cancer is the leading cause of cancer-related mortality worldwide. Diagnosis of lung cancer in an early stage is still a challenge due to the asymptomatic course of early stages of the disease and the lack of a standard screening program for the population. Nowadays, learning about the mechanisms that lead to cancerogenesis in the lung is crucial for the development of new diagnostic and therapeutic strategies. Recently, many studies have proved that cancer stem cells (CSCs) are responsible for the initiation, progression, metastasis, recurrence, and even resistance of chemo- and radiotherapeutic treatment in patients with lung cancer. The expression of pluripotency transcription factors is responsible for stemness properties. In this review, we summarize the current knowledge on the role of CSCs and pluripotency transcription factors in lung carcinogenesis.

Prognostic value of cancer stem cell marker CD133 expression in esophageal carcinoma: A meta-analysis

CD133 has been identified as a putative neoplastic stem cell marker in esophageal carcinoma. However, the prognostic value of CD133 overexpression in patients with esophageal carcinoma remains controversial. A meta-analysis of previous studies was performed, in order to assess the association of CD133 overexpression with the clinicopathological characteristics of esophageal carcinoma patients. A total of 7 studies, including 538 patients, were subjected to the final analysis. Our results indicated that a positive CD133 expression was significantly associated with lymph node metastasis [odds ratio (OR)=3.09, 95% confidence interval (CI): 1.93-4.95; P<0.00001], clinical stage (OR=4.26, 95% CI: 1.55-11.73; P=0.005) and histopathological grade (OR=2.40, 95% CI: 1.16-4.94; P=0.02). There was no statistically significant association of CD133 with depth of invasion (OR=1.89, 95% CI: 0.42-8.43; P=0.41). Based on the results of this study, we concluded that CD133 is an efficient prognostic factor in esophageal carcinoma. Higher CD133 expression is significantly associated with lymph node metastasis, clinical stage and histopathological grade.

SLUG is required for SOX9 stabilization and functions to promote cancer stem cells and metastasis in human lung carcinoma

Cancer stem cells (CSCs) are a promising target for cancer therapy, particularly for metastatic lung cancers, but how CSCs are regulated is largely unknown. We identify two proteins, SLUG (encoded by SNAI2 gene) and SOX9, that are associated with advanced stage lung cancers and are implicated in the regulation of CSCs. Inhibition of either SLUG or SOX9 sufficiently inhibits CSCs in human lung cancer cells and attenuates experimental lung metastasis in a xenograft mouse model. Correlation between SLUG and SOX9 levels was observed remarkably, we therefore sought to explore their mechanistic relationship and regulation. SLUG, beyond its known function as an epithelial-mesenchymal transition transcription factor, was found to regulate SOX9 by controlling its stability via a post-translational modification process. SLUG interacts directly with SOX9 and prevents it from ubiquitin-mediated proteasomal degradation. SLUG expression and binding are necessary for SOX9 promotion of lung CSCs and metastasis in a mouse model. Together, our findings provide a novel mechanistic insight into the regulation of CSCs via SLUG-SOX9 regulatory axis, which represents a potential novel target for CSC therapy that may overcome cancer chemoresistance and relapse.

Prognostic value of cancer stem cell marker CD133 in ovarian cancer: a meta-analysis

OBJECTIVE

To investigate the association between CD133 expression and prognosis and clinicopathological features of ovarian cancer.

METHODS

The electronic and manual searches were performed through the database of PubMed Chinese Wanfang databases (up to September 15, 2014) was performed using the following keywords ovarian cancer, CD133, AC133, prominin-1. Meta-analysis was performed by using Review Manager 5.2 and the outcomes included the overall survival and various clinicopathological features.

RESULTS

A total of 1051 ovarian cancer patients from 8 studies were included. Meta-analysis showed that overexpression of CD133 was highly correlated with reduced 2-year overall survival (OR = 1.67, 95% CI: 1.06-2.63, P = 0.03, fixed-effect). With respect to clinicopathological features, CD133 level was positively correlated with tumor stage (OR = 0.26, 95% CI: 0.12-0.58, P = 0.001 random-effect). But not correlated with patients' age (OR = 1.12, 95% CI: 0.68-1.86, P = 0.65 fixed-effect), tumor grade (OR = 1.20, 95% CI: 0.06-1.62, P = 0.17 random-effect), histological type (OR = 1.10, 95% CI: 0.82-1.47, P = 0.54 fixed-effect) and response to treatment (OR = 0.84, 95% CI: 0.61-1.16, P = 0.29 fixed-effect).

CONCLUSION

On the basis of current retrospective evidence, the present meta-analysis indicated that high level of CD133 expression trends to correlate with a worse prognosis in patients with ovarian cancer.

Liver metastasis predicts poorer prognosis in stage IV lung adenocarcinoma patients receiving first-line gefitinib

OBJECTIVES

Gefitinib is currently used as a first-line therapy in patients of advanced non-small cell lung cancer (NSCLC) with susceptible epidermal growth factor receptor (EGFR) mutations. However, treatment outcomes of these patients vary. This study was conducted to evaluate the impact of specific metastatic sites on treatment outcomes of patients with stage IV lung adenocarcinoma with susceptible EGFR mutations receiving first-line gefitinib, focusing on the impact of liver metastasis.

MATERIALS AND METHODS

Between October 2009 and April 2014, patients of stage IV lung adenocarcinoma harboring EGFR mutation in exon 19 or 21, who received first-line gefitinib treatment, were enrolled in two hospitals and followed until December 22, 2014. The impacts of various clinical features, including sex, age, smoking history, performance status, EGFR mutation site, metastatic sites, etc., on progression-free survival (PFS) and overall survival (OS) were analyzed.

RESULTS

A total of 148 patients were eligible for analysis. Patients with liver metastasis on initial diagnosis (n=19) had shorter PFS and OS than those without liver metastasis did (median of PFS, 6.7 vs. 11.2 months, p<0.0001; median of OS, 9.2 vs. 17.5 months, p<0.0001). Multivariable Cox regression analysis showed liver metastasis was an independent poor prognostic factor for PFS (HR=2.939 [95% CI: 1.729-4.997], p<0.0001) and OS (HR=3.300 [95% CI: 1.708-6.373], p=0.0004).

CONCLUSION

Liver metastasis predicts poorer PFS and OS in stage IV lung adenocarcinoma patients with susceptible gene mutations receiving first-line gefitinib. Further study is warranted to elucidate the underlying mechanisms and find treatment modalities to improve prognosis of these patients.

High CD133 expression in the nucleus and cytoplasm predicts poor prognosis in non-small cell lung cancer

Objective. The aim of this study was to investigate the expression of Prominin-1 (CD133) in cancer cells and its potential value as a prognostic indicator of survival in patients with non-small cell lung cancer (NSCLC). Methods. Cancerous tissues and matched normal tissues adjacent to the carcinoma from 239 NSCLC patients were obtained immediately after surgery. Immunohistochemistry of tissue microarrays was used to characterize the expression of CD133 in NSCLC and adjacent tissues. The correlation of CD133 expression with clinical characteristics and prognosis was determined by statistical analysis. Results. CD133 protein expression levels in both the cytoplasm and nucleus were significantly higher in NSCLC tissues compared with corresponding peritumoral tissue (P < 0.05). CD133 expression in the nucleus of NSCLC cells was related to tumor diameter (P = 0.027), tumor differentiation (P < 0.001), and TNM stage (P = 0.007). Kaplan-Meier survival and Cox regression analyses revealed that high CD133 expression in the nucleus was an independent predictor of poor prognosis of NSCLC, as was high cytoplasmic CD133 expression (P < 0.001). Conclusion. Our findings provide the first evidence that high expression of CD133 in both the nucleus and cytoplasm is associated with poor prognosis in NSCLC.