Comprehensive molecular analyses of a 7-m6A-related lncRNAs signature for prognosis, tumor immunity and therapeutic effect in patients with hepatocellular carcinoma.

Hepatocellular carcinoma is the most common form of liver tumor. m6A modification and noncoding RNA show indispensable roles in HCC. We sought to establish and verify an appropriate m6A-related long noncoding RNA prognostic tool for predicting hepatocellular carcinoma progression. We extracted the RNA expression levels and the clinicopathologic data from GTEx and TCGA databases. Multivariate Cox regression analysis and receiver operating characteristic curves were performed to test the model's predictive ability. We further built a nomogram for overall survival according to the risk score and clinical features. A competing endogenous RNA network and Gene Ontology assessment were implemented to identify related biological mechanisms and processes. By bioinformatics analysis, a risk model comprising GABPB1-AS1, AC025580.1, LINC01358, AC026356.1, AC009005.1, HCG15, and AC026368.1 was built to offer a prognostic prediction for hepatocellular carcinoma independently. The prognostic tool could better prognosticate hepatocellular carcinoma patients' survival than other clinical characteristics. Then, a nomogram with risk score and clinical characteristics was created, which had strong power to calculate the survival probability in hepatocellular carcinoma. The immune-associated processes involving the differentially expressed genes between the two subgroups were displayed. Analyses of prognosis, clinicopathological characteristics, tumor mutation burden, immune checkpoint molecules, and drug response showed significant differences among the two risk subtypes, hinting that the model could appraise the efficacy of immunotherapy and chemotherapy. The tool can independently predict the prognosis in patients with hepatocellular carcinoma, which benefits drug selection in hepatocellular carcinoma patients.

PTOV1-AS1 desensitizes colorectal cancer cells to 5-FU through depressing miR-149-5p to activate the positive feedback loop with Wnt/ß-catenin pathway.

5-Fluorouracil is a commonly used chemotherapy drug for colorectal cancer. Resistance to 5-Fluorouracil remains a challenge. This research aimed to explore the mechanism of 5-Fluorouracil resistance in colorectal cancer. RT-qPCR and Western blot were used to determine the RNA and protein expression in both cells and exosome. Assays in vitro and in vivo were performed to measure the role of miR-149-5p in colorectal cancer cells. RIP, luciferase activity report, and RNA pulldown assay were applied to detect the association of PTOV1-AS1, SUV39H1, miR-149-5p, and FOXM1. MiR-149-5p was down-expressed in 5-Fluorouracil-resistant cells. MiR-149-5p enhanced the effectiveness of 5-Fluorouracil both in vitro and in vivo. Sensitive colorectal cancer cells released exosomal miR-149-5p to sensitize resistant cells to chemotherapy. Mechanistically, miR-149-5p targeted the FOXM1 to inactivate Wnt/ß-catenin pathway, and PTOV1-AS1 recruited SUV39H1 to suppress miR-149-5p transcription, in turn activating Wnt/ß-catenin pathway, and forming a positive feedback loop with FOXM1. PTOV1-AS1 inhibits miR-149-5p by a positive feedback loop with FOXM1-mediated Wnt/ß-catenin pathway, which provides insights into a potential novel target for enhancing the effectiveness of chemotherapy in colorectal cancer patients.

Risk of second primary malignancy in adults with pulmonary high-grade neuroendocrine carcinoma (HGNEC).

BACKGROUND: Pulmonary high-grade neuroendocrine carcinoma (HGNEC) has a rising incidence of developing second primary malignancies (SPMs). This study is the first population-based analysis to quantify the SPM risks among survivors of lung HGNEC. METHODS: We used the Surveillance, Epidemiology, and End Results (SEER) database to calculate standardized incidence ratio (SIR) and absolute excess risk (AER) between 2000 and 2016 for patients with pulmonary HGNEC. RESULTS: The data of 1161 patients with SPMs were retrieved from the SEER database. The ratio of observed/expected number of SPMs in pulmonary HGNEC was 1.53. Solid tumours comprised 91% of all second malignancies in lung HGNEC patients, with the most common cancers reported in the oral cavity and pharynx, the urinary and respiratory systems CONCLUSIONS: Our study observed an increased risk of SPMs among patients with pulmongnancies.

The Role of Canonical Wnt Signaling in Regulating Radioresistance.

Radioresistance is a major obstacle in radiotherapy for cancer, and strategies are needed to overcome this problem. Currently, radiotherapy combined with targeted therapy such as inhibitors of phosphoinosotide 3-kinase/Akt and epidermal growth factor receptor signaling have become the focus of studies on radiosensitization. Apart from these two signaling pathways, which promote radioresistance, deregulation of Wnt signaling is also associated with the radioresistance of multiple cancers. Wnts, as important messengers in the tumor microenvironment, are involved in cancer progression mainly via canonical Wnt signaling. Their role in promoting DNA damage repair and inhibiting apoptosis facilitates cancer resistance to radiation. Thus, it seems reasonable to target Wnt signaling as a method for overcoming radioresistance. Many small-molecule inhibitors that target the Wnt signaling pathway have been identified and shown to promote radiosensitization. Therefore, a Wnt signaling inhibitor may help to overcome radioresistance in cancer therapy.

MiRNA-26a Contributes to the Acquisition of Malignant Behaviors of Doctaxel-Resistant Lung Adenocarcinoma Cells through Targeting EZH2.

BACKGROUND/AIMS: Accumulating evidence revealed that microRNAs (miRNAs) have been demonstrated as critical molecules in tumor development and progression. MiR-26a, located in a fragile chromosomal region associated with various human cancer, has been reported to be involved in regulating various cellular process, such as proliferation, apoptosis and invasion through targeting multiple oncogene. Docetaxel-mediated chemotherapy has been applied in improving the survival and prognosis of patients with advanced lung adenocarcinoma (LAD). However, chemoresistance remains a major impediment to clinical application of this agent. It has been presented that decreased miR-26a expression lead to cisplatin resistance and promoted growth and migration in human lung cancer. Enhancer of zeste homolog 2 (EZH2) is the target of miR-26a. The present study aimed to investigate the function of miR-26a/EZH2 in the acquisition of malignant behaviors of LAD. METHODS: MiR-26a and EZH2 expression levels in the dcetaxel-insensitive groups (n = 19) and the docetaxel-sensitive groups (n = 18) were assessed by qRT-PCR. Colony formation assay, flow cytometric analysis, wound healing assay, cell transwell assays and western blotting were performed to assess the effects of miR-26a on proliferation, apoptosis and epithelial-to-mesenchymal (EMT) phenotypes in docetaxel resistant LAD cells in vitro. Xenograft transplantation, immunohistochemistry, tunel assays and western blotting assays were employed to demonstrate the role of miR-26a in docetaxel resistant LAD cells in vivo. The expression level of EZH2 in docetaxel-resistant LAD cells and corresponding parental cells was detected by qRT-PCR and western blotting. The relationship between miR-26a and EZH2 was confirmed by luciferase reporter assay. And rescue assays were performed to further confirm that miRNA-26a contributes to the acquisition of malignant behaviors of docetaxel-resistant LAD cells through targeting EZH2. RESULTS: MiR-26a was significantly down-regulated in the dcetaxel-insensitive groups (n = 19) compared with the docetaxel-sensitive groups (n = 18) assessed by qRT-PCR. MiR-26a decreased the proliferation, increased the apoptosis rate and reversed EMT to MET of docetaxel-resistant LAD cells both in vivo and vitro. EZH2 was confirmed as target of miR-26a. Rescue assays further verified that the function of miR-26a exerts in docetaxel-resistant LAD cells is through targeting EZH2. CONCLUSIONS: Our data revealed that overexpression of miR-26a in docetaxel-resistant LAD cells could decrease the proliferation, increase the apoptosis rate and reverse EMT to MET of docetaxel-resistant LAD cells both in vivo and vitro and such function is partially exerted via downregulating EZH2. MiR-26a/EZH2 signal pathway makes contribute to the malignant phenotype of docetaxel-resistant of LAD cells which indicated that miR-26a exerts pivotal functions in the molecular etiology of chemoresistant lung adenocarcinoma.

EP300 regulates the SLC16A1-AS1-AS1/TCF3 axis to promote lung cancer malignancies through the Wnt signaling pathway.

Objective: To investigate the regulatory mechanism of EP300 in the interaction between SLC16A1-AS1 and TCF3 to activate the Wnt pathway, thereby promoting malignant progression in lung cancer. Methods: In lung cancer cell lines, SLC16A1-AS1 was knocked down, and the impact of this knockdown on the malignant progression of lung cancer cells was assessed through clonogenic assays, Transwell assays, and apoptosis experiments. The regulatory relationship between EP300 and SLC16A1-AS1 was investigated through bioinformatic analysis and ChIP experiments. The expression of SLC16A1-AS1 and TCF3 in 56 paired lung cancer tissues was examined using RT-qPCR, and their correlation was analyzed. The interaction between TCF3 and SLC16A1-AS1 was explored through bioinformatic analysis and CoIP experiments. Activation of the Wnt/ß-catenin pathway was assessed by detecting the accumulation of ß-catenin in the nucleus through Western blotting. The role of EP300 in regulating the effect of SLC16A1-AS1/TCF3-mediated Wnt/ß-catenin signaling on lung cancer malignant progression was validated through in vitro and in vivo experiments. Results: SLC16A1-AS1 is highly expressed in lung cancer and regulates its malignant progression. EP300 mediates histone modifications on the SLC16A1-AS1 promoter, thus controlling its expression. SLC16A1-AS1 exhibits specific interactions with TCF3, and the SLC16A1-AS1/TCF3 complex activates the Wnt/ß-catenin pathway. EP300 plays a critical role in regulating the impact of SLC16A1-AS1/TCF3-mediated Wnt/ß-catenin signaling on lung cancer malignant progression. Conclusion: EP300 regulates the SLC16A1-AS1/TCF3-mediated Wnt/ß-catenin signaling pathway, influencing the malignant progression of lung cancer.

Efficacy and safety of irinotecan combined with raltitrexed or irinotecan monotherapy for salvage chemotherapy of esophageal squamous cell cancer: A prospective, open label, randomized phase II study.

BACKGROUND: Esophageal squamous cell cancer (ESCC) accounts for approximately 90% of esophageal cancer cases in China. There are no standard regimens for second or third-line chemotherapy of metastatic squamous esophageal cancer. The objective of this study was to investigate the security and effectiveness of irinotecan combined with raltitrexed or irinotecan monotherapy for salvage chemotherapy of ESCC. METHODS: One hundred and twenty-eight patients with metastatic ESCC confirmed by histopathology were enrolled into this study. These patients had failure of the first-line chemotherapy combination of fluorouracil or platinum or paclitaxel and had not undergone chemotherapy with irinotecan or raltitrexed previously. Patients were randomly divided into irinotecan combined with raltitrexed group (experiment group) and irinotecan monotherapy group (control group). Overall survival (OS) and progression-free survival (PFS) were the primary endpoint. RESULTS: In the control group, the median PFS (mPFS) and median OS (mOS) of patients were 3.37 and 5.3 months. In the experiment group, mPFS and mOS were 3.91 and 7.0 months. There was statistical significance of PFS and OS between two groups (PFS P = 0.002, OS P = 0.01). In subgroup analysis, in the second-line treatment, the mPFS of control and experiment group, was 3.90 and 4.60 months, mOS was 6.95 and 8.5 months, which was statistically significant differences between the two groups. (PFS P = 0.001, OS P = 0.005), In the third-line and beyond treatment, mPFS of control and experiment group was 2.80 and 3.19 months, mOS were 4.5 and 4.8 months. But there was no significant difference of PFS or OS between the two groups (PFS P = 0.19, OS P = 0.31). There was no statistical significance of toxicity side effects between two groups. CONCLUSIONS: The PFS and OS of irinotecan plus raltitrexed may be better than that of irinotecan monotherapy, especially in second line treatment, which should be confirmed with a phase III study including much more patients.

Prognostic Value of an m6A RNA Methylation Regulator-Based Signature in Patients with Hepatocellular Carcinoma.

PURPOSES: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in the world. Recent researches have demonstrated that m6A methylation regulators play a key role in various cancers, such as gastric cancer and colon adenocarcinoma. Several m6A methylation regulators are reported to predict the prognosis of HCC. Therefore, there is a need to further identify the predictive value of m6A methylation regulators in HCC. METHODS: We utilized The Cancer Genome Atlas (TCGA) database to obtain the gene expression profile of m6A RNA methylation regulators and clinical information for patients with HCC. Besides, we identified two clusters of HCC with various clinical factors by consensus clustering analysis. Then the least absolute shrinkage and selection operator (LASSO) and the Cox regression analysis were applied to construct a prognostic signature. RESULTS: Except for ZC3H13 and METTL14, a majority of the thirteen m6A RNA methylation regulators were significantly overexpressed in HCC specimens. HCC patients were classified into two groups (cluster 1 and cluster 2). The cluster 1 was with a significantly worse prognosis than cluster 2, and most of the 13 known m6A RNA methylation regulators were upregulated in cluster 1. Besides, we developed a prognostic signature consisting of YTHDF2, YTHDF1, METTL3, KIAA1429, and ZC3H13, which could successfully differentiate high-risk patients. More importantly, univariate and multivariate Cox regression analysis indicated that the signature-based risk score was an independent prognostic factor for patients with HCC. CONCLUSIONS: Our study showed these five m6A RNA methylation regulators can be used as practical and reliable prognostic tools of HCC, which might have potential value for therapeutic strategies.

Wnt signaling induces radioresistance through upregulating HMGB1 in esophageal squamous cell carcinoma.

Although many articles have uncovered that Wnt signaling is involved in radioresistance, the mechanism is rarely reported. Here we generated two radioresistant cells rECA109 and rKyse150 from parental esophageal cancer cells ECA109 and Kyse150. We then found that Wnt signaling activity was higher in radioresistant cells and was further activated upon ionizing radiation (IR) exposure. In addition, radioresistant cells acquired epithelial-to-mesenchymal transition (EMT) properties and stem quality. Wnt signaling was then found to be involved in radioresistance by promoting DNA damage repair. In our present study, high-mobility group box 1 protein (HMGB1), a chromatin-associated protein, was firstly found to be transactivated by Wnt signaling and mediate Wnt-induced radioresistance. The role of HMGB1 in the regulation of DNA damage repair with the activation of DNA damage checkpoint response in response to IR was the main cause of HMGB1-induced radioresistance.

Cancer associated fibroblasts: An essential role in the tumor microenvironment.

Fibroblasts in the tumor stroma are well recognized as having an indispensable role in carcinogenesis, including in the initiation of epithelial tumor formation. The association between cancer cells and fibroblasts has been highlighted in several previous studies. Regulation factors released from cancer-associated fibroblasts (CAFs) into the tumor microenvironment have essential roles, including the support of tumor growth, angiogenesis, metastasis and therapy resistance. A mutual interaction between tumor-induced fibroblast activation, and fibroblast-induced tumor proliferation and metastasis occurs, thus CAFs act as tumor supporters. Previous studies have reported that by developing fibroblast-targeting drugs, it may be possible to interrupt the interaction between fibroblasts and the tumor, thus resulting in the suppression of tumor growth, and metastasis. The present review focused on the reciprocal feedback loop between fibroblasts and cancer cells, and evaluated the potential application of anti-CAF agents in the treatment of cancer.

Long noncoding RNA ROR regulates chemoresistance in docetaxel-resistant lung adenocarcinoma cells via epithelial mesenchymal transition pathway.

Emerging evidence indicates that the dysregulation of long non-coding RNAs (lncRNAs) contributes to the development and progression of lung adenocarcinoma (LAD), however the underlying mechanism of action of lncRNAs remains unclear. It is well known that the effective treatment of cancers has been hindered by drug resistance in the clinical setting. Epithelial-mesenchymal transition (EMT) has been recognized to be involved in acquiring drug resistance, cell migration and invasion properties in several types of cancer. Docetaxel-resistant LAD cells established previously in our lab present chemoresistant and mesenchymal features. Long intergenic non-protein coding RNA, regulator of reprogramming (linc-ROR), was first discovered in induced pluripotent stem cells (iPSCs) and was upregulated in docetaxel-resistant LAD cells. In this study, we tried to make clarification of lincRNA-related mechanisms underlying EMT followed by acquired resistance to chemotherapy in LAD. In order to hit the mark, we made use of multiple methods including microarray analysis, qRT-PCR, western blotting analysis, loss/gain-of-function analysis, luciferase assays, drug sensitivity assays, wound-healing assay and invasion assay. We found that decreased expression of linc-ROR effectively reversed EMT in docetaxel-resistant LAD cells and sensitized them to chemotherapy. The function of linc-ROR exerted in LAD cells depended on the sponging of miR-145, therefore, releasing the miR-145 target FSCN1, and thus contributing to the acquisition of chemoresistance and EMT phenotypes of docetaxel-resistant LAD cells. Our findings revealed that linc-ROR might act as potential therapeutic target to overcome chemotherapy resistance in LAD.

Hypoxia induced CCL28 promotes angiogenesis in lung adenocarcinoma by targeting CCR3 on endothelial cells.

Tumor hypoxia is one of the important features of lung adenocarcinoma. Chemokines might mediate the effects caused by tumor hypoxia. As confirmed in tumor tissue and serum of patients, CC chemokine 28 (CCL28) was the only hypoxia induced chemokine in lung adenocarcinoma cells. CCL28 could promote tube formation, migration and proliferation of endothelial cells. In addition, angiogenesis was promoted by CCL28 in the chick chorioallantoic membrane and matrigel implanted in dorsal back of athymic nude mice (CByJ.Cg-Foxn1(nu)/J). Tumors formed by lung adenocarcinoma cells with high expression of CCL28 grew faster and had a higher vascular density, whereas tumor formation rate of lung adenocarcinoma cells with CCL28 expression knockdown was quite low and had a lower vascular density. CCR3, receptor of CCL28, was highly expressed in vascular endothelial cells in lung adenocarcinoma when examining by immunohistochemistry. Further signaling pathways in endothelial cells, modulated by CCL28, were analyzed by Phosphorylation Antibody Array. CCL28/CCR3 signaling pathway could bypass that of VEGF/VEGFR on the levels of PI3K-Akt, p38 MAPK and PLC gamma. The effects could be neutralized by antibody against CCR3. In conclusion, CCL28, as a chemokine induced by tumor hypoxia, could promote angiogenesis in lung adenocarcinoma through targeting CCR3 on microvascular endothelial cells.

Cancer-associated fibroblasts treated with cisplatin facilitates chemoresistance of lung adenocarcinoma through IL-11/IL-11R/STAT3 signaling pathway.

Cancer-associated fibroblasts (CAF) are recognized as one of the key determinants in the malignant progression of lung adenocarcinoma. And its contributions to chemoresistance acquisition of lung cancer has raised more and more attention. In our study, cancer associated fibroblasts treated with cisplatin conferred chemoresistance to lung cancer cells. Meanwhile, Interleukin-11(IL-11) was significantly up-regulated in the CAF stimulated by cisplatin. As confirmed in lung adenocarcinoma cells in vivo and in vitro, IL-11 could protect cancer cells from cisplatin-induced apoptosis and thus promote their chemoresistance. Furthermore, it was also observed that IL-11 induced STAT3 phosphorylation and increased anti-apoptotic protein Bcl-2 and Survivin expression in cancer cells. The effect could be abrogated by suppressing STAT3 phosphorylation or silencing IL-11Rα expression in cancer cells. In conclusion, chemotherapy-induced IL-11 upregulation in CAF promotes lung adenocarcinoma cell chemoresistance by activating IL-11R/STAT3 anti-apoptotic signaling pathway.

DNA methylation of DKK3 modulates docetaxel chemoresistance in human nonsmall cell lung cancer cell.

Dickkopf-related protein 3 (DKK3) gene, as a tumor suppressor gene, has been discovered in various cancers, but its relationship with tumor chemoresistance is still unclear. In this study, this laboratory detected that DNA methylation contributes to the downregulation of DKK3 in docetaxel resistance of human lung cancer cells and its possible biochemical mechanism. DKK3 has been proved to be downregulated by hypermethylation in docetaxel-resistant lung cancer cells. Upregulation of DKK3 can reverse the chemoresistance of docetaxel-resistant cell lines in vitro by growth inhibition and enhancement of apoptosis. Conversely, downregulation of DKK3 could induce parental human lung cancer cells insensitivity to docetaxel by promoting proliferative capacity and inhibiting apoptosis of cancer cells. In addition, the authors observed that overexpression of DKK3 might decrease the expression of P-glycoprotein. All results suggested that epigenetic downregulation of DKK3 leads to docetaxel resistance in human nonsmall cell lung cancer (NSCLC) cells by increased expression of P-glycoprotein. DKK3 may reveal a novel molecular target for docetaxel resistance for NSCLC patients in the future.

Bevacizumab improves the antitumor efficacy of adoptive cytokine-induced killer cells therapy in non-small cell lung cancer models.

Cytokine-induced killer cells (CIK cells) are a heterogeneous population of cells generated from peripheral blood mononuclear cells, which share phenotypic and functional properties with both natural killer and T cells. CIK cells therapy, as an adoptive immunotherapy with strong antitumor activity in vitro, represents a promising approach for the treatment of a broad array of malignant tumors. However, clinical trials in CIK cells therapy did not show more noticeable improvement as anticipated in cure rates or long-term survival. Possible explanations are that abnormal tumor vasculature and hypoxic microenvironment may highly limit the therapeutic benefits of CIK cells therapy. We hypothesized that antiangiogenesis therapy could enhance the antitumor efficacy of CIK cells by normalizing tumor vasculature and modulating tumor hypoxic microenvironment. In this study, we combined bevacizumab and adoptive CIK cells therapy in the treatment of lung adenocarcinoma bearing murine models. Flow cytometry, intravital microscopy and immunohistochemistry were applied to detect tumor vasculature and hypoxic microenvironment as well as the infiltration of CIK cells. The results indicated that bevacizumab-combined adoptive CIK cells had synergistic inhibition effects on the growth of lung adenocarcinoma. Hypoxia significantly inhibited the infiltration of CIK cells into tumor tissue. Bevacizumab could normalize tumor vasculature and decrease tumor hypoxic area. Furthermore, combination therapy enhanced more CIK cells infiltrated into tumor compared with other treatment. Bevacizumab improves antitumor efficacy of CIK cells transfer therapy in non-small cell lung cancer (NSCLC). The study provides a reasonable and beneficial strategy that combined antiangiogenesis therapy with CIK cells therapy for patients of advanced stage non-small cell lung cancer.

Synergistic antitumor effect of combining metronomic chemotherapy with adoptive cell immunotherapy in nude mice.

Adoptive cell immunotherapy with cytokine-induced killer cell (CIK cell) represents a promising non-toxic anticancer therapy. However, the clinical efficacy of CIK cells is limited because of abnormal tumor vasculature. Metronomic chemotherapy shows promising anticancer activity by its potential antiangiogenic effect and reduced toxicity. We hypothesized that metronomic chemotherapy with paclitaxel could improve the antitumor effect of adoptive CIK cell immunotherapy. Mice health status was analyzed by measuring mice weight and observing mice behavior. Immunohistochemistry was used to investigate the recruitment of CIK cells, the expression of endothelial cell molecules, as well as the hypoxic tumor area. Metronomic paclitaxel synergized with adoptive CIK cell immunotherapy to inhibit the growth of non-small cell lung cancer (NSCLC). Metronomic paclitaxel reduced hypoxic tumor area and increased CIK cell infiltration. Hypoxia impeded the adhesion of CIK cells and reduced the expression of endothelial cell adhesion molecules. In vivo studies demonstrated that more CIK cells were found in endothelial cell adhesion molecules high expressed area. Our study provides a new rationale for combining metronomic chemotherapy with adoptive cell immunotherapy in the treatment of xenograft NSCLC tumors in immunodeficient mice. Further clinical trials integrating translational research are necessary to better evaluate the clinical benefit of this promising approach.

Expression of monocyte chemotactic protein-1/CCL2 in gastric cancer and its relationship with tumor hypoxia.

AIM: To investigate the expression and prognostic value of CCL2 in gastric cancer, as well as its relationship with tumor hypoxia. METHODS: Tumor tissues from 68 gastric cancer patients (GC) were analyzed, and the expression of CCL2 and hypoxia-inducible factor 1 alpha (HIF-1α) in tumor tissues was detected by immunohistochemistry. Statistical evaluations that were used included univariate log-rank tests of Kaplan-Meier curves and multivariate Cox regression model analysis. RESULTS: CCL2 was highly expressed in 66.2% (45/68) of gastric cancer specimens. The distribution of CCL2 expression in tumor tissue was consistent with that of HIF-1α. Patients with high CCL2 expression in GC had a lower overall survival rate [50.6 mo (95%CI: 44.44-56.93) vs 64.6 mo (95%CI: 60.27-68.94), P = 0.013]. CONCLUSION: CCL2 expression correlates closely with HIF-1α expression in gastric cancer. CCL2 may be an independent prognostic marker for GC.