Yufeng Cheng

Liquid biopsy: a step forward towards precision medicine in urologic malignancies

There is a growing trend towards exploring the use of a minimally invasive “liquid biopsy” to identify biomarkers in a number of cancers, including urologic malignancies. Multiple aspects can be assessed in circulating cell-free DNA, including cell-free DNA levels, integrity, methylation and mutations. Other prospective liquid biopsy markers include circulating tumor cells, circulating RNAs (miRNA, lncRNAs and mRNAs), cell-free proteins, peptides and exosomes have also emerged as non-invasive cancer biomarkers. These circulating molecules can be detected in various biological fluids, including blood, urine, saliva and seminal plasma. Liquid biopsies hold great promise for personalized medicine due to their ability to provide multiple non-invasive global snapshots of the primary and metastatic tumors. Molecular profiling of circulating molecules has been a stepping-stone to the successful introduction of several non-invasive multi-marker tests into the clinic. In this review, we provide an overview of the current state of cell-free DNA-based kidney, prostate and bladder cancer biomarker research and discuss the potential utility other circulating molecules. We will also discuss the challenges and limitations facing non-invasive cancer biomarker discovery and the benefits of this growing area of translational research.

Prognostic and diagnostic potential of miR-146a in oesophageal squamous cell carcinoma.

Background:Accumulating evidence indicates that dysregulated microRNA-146a (miR-146a) is involved in tumour genesis and cancer progression. We aimed to evaluate its expression level and the potential for the diagnosis and prognosis in oesophageal squamous cell cancer (ESCC).Methods:We examined miR-146a expression in 62 pairs of ESCC cancerous and matched paracancerous tissue, 115 formalin-fixed paraffin-embedded (FFPE) tissue samples and serum samples from 154 ESCC patients and 154 healthy volunteers using quantitative reverse transcription–PCR (qRT–PCR). Kaplan–Meier method, Cox regression and receiver-operating characteristic (ROC) curve analysis were applied to analyse its prognostic and diagnostic value.Results:MicroRNA-146a expression level was significantly decreased in ESCC tissue compared with paracancerous tissue (P<0.001). Its regulation level was negatively associated with T factor and TNM stage. Kaplan–Meier curve revealed that its downregulation level predicted worse overall survival (OS) and progression-free survival (PFS). Both univariate and multivariate analyses identified miR-146a expression as independent prognostic factor for OS and PFS. Serum miR-146a was significantly reduced in ESCC patients than in healthy controls (P<0.001). Area under the curve ROC value, sensitivity and specificity for this marker were 0.863±0.033, 85.7% and 68.6% in the Discovery Group, and 0.891±0.027, 82.1% and 83.3% in the Validation Group.Conclusions:MicroRNA-146a is significantly reduced in cancerous tissue and serum samples of ESCC patients. It is an ideal biomarker for the prognosis and diagnosis of ESCC.

miR-146a-5p mediates epithelial–mesenchymal transition of oesophageal squamous cell carcinoma via targeting Notch2

Background:Our previous study found that dysregulated microRNA-146a-5p (miR-146a-5p) is involved in oesophageal squamous cell cancer (ESCC) proliferation. This article aimed to evaluate its detailed mechanisms in ESCC epithelial–mesenchymal transition (EMT) progression.Methods:Invasion assay, qRT-PCR and western blotting were used to validate the roles of miR-146a-5p and Notch2 in EMT progression. miRNA target gene prediction databases and dual-luciferase reporter assay were used to validate the target gene.Results:miR-146a-5p inhibitor led to increase of invaded ESCC cells, while miR-146a-5p mimics inhibited invasion ability of ESCC cells. Protein level of E-cadherin decreased, whereas those of Snail and Vimentin increased in the anti-miR-146a-5p group, which demonstrated that miR-146a-5p inhibits EMT progression of ESCC cells. miRNA target gene prediction databases indicated the potential of Notch2 as a direct target gene of miR-146a-5p and dual-luciferase reporter assay validated it. Importantly, shRNA-Notch2 restrained EMT and partially abrogated the inhibiting effects of miR-146a-5p on EMT progression of ESCC cells.Conclusions:miR-146a-5p functions as a tumour-suppressive miRNA targeting Notch2 and inhibits the EMT progression of ESCC.

Notch2 as a promising prognostic biomarker for oesophageal squamous cell carcinoma

We aimed to examine Notch2 expression in oesophageal squamous cell carcinoma (ESCC) patients and to evaluate its prognostic potential. Immunohistochemical (IHC) staining, quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis were utilized to investigate the Notch2 expression status and prognostic value. Furtherly, CCK8 and clonogenic assays were conducted to determine if Notch2 inhibition by shRNA could lead to a decrease in the proliferation and survival of ESCC cells. A notably higher Notch2 expression level was found in ESCC tissues at the mRNA (Pu2009<u20090.0001) and protein levels (IHC: Pu2009=u20090.004; western blot: Pu2009=u20090.021). Log-rank analysis demonstrated that Notch2 overexpression was significantly associated with worse overall survival (OS) (29.1% vs. 49.1%; Pu2009=u20090.013) and progression-free survival (PFS) (15.3% vs. 34.4%; Pu2009=u20090.006) rates in ESCC patients. The multivariate analysis revealed Notch2 as an independent prognostic factor for OS and PFS (Pu2009=u20090.002 and 0.006, resp.). Besides, in vitro assays showed that OD450 values and colony formations were significantly reduced in Notch2-shRNA group (all Pu2009<u20090.0001). In conclusion, these results show that Notch2 is up-regulated in ESCC tissues and could serve as a promising biomarker for identifying individuals with poor prognostic potential.

miR-10b is a prognostic marker in clear cell renal cell carcinoma

Aims Clear cell renal cell carcinoma (ccRCC) is the most common adult kidney cancer. It is an aggressive tumour with unpredictable outcome. The currently used clinical parameters are not always accurate for predicting disease behaviour. miR-10b is dysregulated in different malignancies including RCC. Methods We assessed the clinical utility of miR-10b as a prognostic marker in 250 patients with primary ccRCC. We examined the correlation between miR-10b and clinicopathological parameters. We compared miR-10b expression among different RCC subtypes and normal kidney tissue. Results We observed a stepwise decrease of miR-10b expression from normal kidney to primary ccRCC and a further decrease from primary to metastatic RCC. miR-10b expression was significantly lower in stages III/IV compared with stages I/II (p=0.038). Using a binary cut-off, miR-10b-positive patients had significantly longer disease-free survival (HR=0.47, CI 0.28 to 0.79, p=0.004). In the subgroup of patients with tumour size >4u2005cm, higher miR-10b expression was associated with significant longer disease-free and overall survival (p=0.001 and p=0.036, respectively). miR-10b was significantly downregulated in ccRCC compared with normal kidney (p<0.0001), and oncocytoma (p=0.031). It was also downregulated in chromophobe RCC. In addition, we identified a number of miR-10b-predicted targets and pathways that are involved in tumourigenesis. Conclusions Our data point to miR-10b as a promising prognostic marker in ccRCC with potential therapeutic applications.

Prognostic significance of microRNA-100 in solid tumors: an updated meta-analysis

Objective The aim of this study was to identify prognostic significance of microRNA-100 (miR-100) in solid tumor. Methods Literature search was conducted in databases such as PubMed, Embase, and Web of Science, using the following words “(microRNA-100 OR miR-100 OR mir100) AND (tumor OR neoplasm OR cancer OR carcinoma OR malignancy).” The search was updated up until July 10, 2016. Newcastle–Ottawa scale was used to evaluate the quality of studies. Pooled hazard ratio (HR) with 95% confidence interval (CI) for patients’ survival was calculated by using a fixed-effects or a random-effects model on the basis of heterogeneity. Subgroup analysis, sensitive analysis, and meta-regression were used to investigate the sources of heterogeneity. Publication bias was evaluated by using Begg’s and Egger’s tests. Results A total of 16 articles with 1,501 patients were included in the present meta-analysis. It was demonstrated that a lower expression of miR-100 plays a negative role in the overall survival (OS) of patients with solid tumor (HR =1.92; 95% CI =1.25–2.94). In addition, the association between miR-100 and prognosis was also revealed in the following subgroups: non-small-cell lung cancer (NSCLC; HR =2.46; 95% CI =1.98–3.06), epithelial ovarian cancer (EOC; HR =2.29, 95% CI =1.72–3.04), and bladder cancer (BC; HR =4.14, 95% CI =1.85–9.27). Conclusion This meta-analysis indicates that lower expression of miR-100 is related to poorer OS in patients with solid tumor, especially in those with NSCLC, EOC, and BC. MiR-100 is a promising prognosis predictor and may be a potential target for therapy in the future.

Plasma fibrinogen and serum albumin levels (FA score) act as a promising prognostic indicator in non-small cell lung cancer

Background Evidence implies that preoperative plasma fibrinogen and serum albumin are associated with cancer prognosis. We aimed to explore the prognostic values of the score based on plasma fibrinogen and serum albumin levels (FA score) in non-small cell lung cancer (NSCLC), and to compare that with prognostic nutritional index (PNI). Patients and methods In all, 182 patients pathologically diagnosed with NSCLC were included in this study. Kaplan–Meier survival analysis and multivariate analysis were used in the prognostic analyses. Results High FA score was related to smoking (P=0.005), poor differential grade (P=0.002), and advanced T stage (P<0.001) and tumor, node, and metastases stage (P=0.011). Low PNI showed association with advanced T stage (P=0.030). Kaplan–Meier survival analysis indicated that high FA score and low PNI were associated with poor progression-free survival (PFS; for the FA score, P<0.001; for PNI, P=0.001) and overall survival (OS; for the FA score, P<0.001; for PNI, P=0.013), respectively. Multivariate analysis revealed that FA score was an independent predictor for PFS (P=0.003) and OS (P=0.001) in NSCLC patients. Conclusion The FA score could act as a more promising prognostic predictor than PNI in NSCLC patients who underwent pneumonectomy.

RACK1 induces chemotherapy resistance in esophageal carcinoma by upregulating the PI3K/AKT pathway and Bcl-2 expression

Introduction Accumulating evidence indicates that RACK1 is involved in the progression of tumors. We aimed to evaluate the function of RACK1 in esophageal squamous cell carcinoma (ESCC) and its role in the mechanism of chemotherapy resistance. Materials and methods Transfected ESCC cell lines with plasmids expressed shRACK1 or open reading frame (ORF) targeting RACK1 and established stable cell lines. We then examined the effects of RACK1 on cell proliferation and chemotherapy resistance in ESCC cell lines, and the expression of AKT, pAKT, ERK1/2, Bcl-2, and Bim was introduced to further detect the association between RACK1 and chemotherapy resistance. Results The proliferation ability of ESCC cells was improved in the overexpression RACK1 groups (P<0.001) and decreased in the transfected shRACK1 groups (P<0.001) compared with the control ones. Meanwhile, upregulation of RACK1 significantly suppressed cisplatin-induced apoptosis in Eca109 and EC9706 cells, while downregulation of RACK1 promoted the sensitivity compared to the control group (Eca109: P<0.001 for shRACK1, P<0.01 for shNC, and P<0.001 for overexpression group; EC9706: P<0.001 for shRACK1, P<0.001 for shNC, and P<0.05 for overexpression group). Furthermore, we found that RACK1 could activate the PI3K/AKT pathway and increase the expression level of Bcl-2 in ESCC, which leads to the enhancement of chemoresistance in ESCC. Conclusion RACK1 promotes proliferation and chemotherapy resistance in ESCC by activating the PI3K/AKT pathway and upregulating the Bcl-2 expression.

The miRNA-kallikrein interaction: a mosaic of epigenetic regulation in cancer

Abstract The kallikrein-related peptidases (KLKs) constitute a family of 15 highly conserved serine proteases with trypsin- and chymotrypsin-like activities. Dysregulated expression and/or aberrant activation of KLKs has been linked to various pathophysiological processes, including cancer. Many KLKs have been identified as potential cancer biomarkers. microRNAs (miRNAs) are a class of small non-coding RNAs that regulate gene expression by pairing to the 3′ untranslated region (UTR) of complimentary mRNA targets. miRNAs are dysregulated in many cancers, including prostate, kidney and ovarian cancers. Several studies have shown that miRNAs are involved in the post-transcriptional regulation of KLKs. However, recent evidence suggests that miRNAs can also act as downstream effectors of KLKs. In this review, we provide an update on the epigenetic regulation of KLKs by miRNAs. We also present recent experimental evidence that supports the regulatory role of KLKs on miRNA networks. The potential diagnostic and therapeutic applications of miRNA-kallikrein interactions are also discussed.

Effect of ABO Blood Group on Survival of Resected Lung Cancer Patients: A Retrospective Study

Materials and methods: A total of 139 patients with lung cancer who underwent curative surgery from January 2009 to November 2010 were enrolled in this retrospective study. Besides clinicopathological prognostic factors, we evaluated the prognostic value of ABO blood type on survival. Univariate analysis was performed by Kaplan-Meier survival analysis and multivariate analysis by Cox Regression Hazard model to measure 5-year Overall survival (OS), Progression free survival (PFS), Distant metastasis free survival (DMFS), Relapse free survival(RFS).