Gene expression analyses identify a relationship between stanniocalcin 2 and the malignant behavior of colorectal cancer

Use of exosome transcriptome-based analysis to identify novel biomarkers in patients with locally advanced esophageal squamous cell carcinoma undergoing neoadjuvant chemoradiotherapy

Background

The prognosis of esophageal squamous cell carcinoma (ESCC) is improved by neoadjuvant chemoradiotherapy (nCRT), especially for patients with pathologic complete response (pCR). Despite the efforts to predict treatment response using multimodality, no molecule has proven to be a strong biomarker. This study aimed to profile the expression of exosome transcriptome that could predict pCR in ESCC before and after nCRT.

Methods

We collected paired blood samples of 15 patients with ESCC who received nCRT and radical surgery. They were divided into 3 groups: (A) residual tumor in the first clinical response evaluation (CRE-1), (B) no residual tumor in CRE-1 but with residual tumor in CRE-2 which was performed after 5-6 weeks, and (C) no residual tumor in CRE-1 or CRE-2. For each patient, the blood sample was collected before nCRT (time point 0); and then 6 weeks after nCRT, the clinical response was evaluated, and another blood sample was collected (time point 1).

Results

Using the intersection of different sets, we found 23 progression-associated messenger RNAs (mRNAs) and 67 remission-associated mRNAs. Between remission-associated mRNAs and the targets of progression-associated (carcinogenic) microRNAs (miRNAs), the intersection was acquired, and 2 miRNA-mRNA networks (IFIT2-miR-3615-IFIT2-miR-484 and BTN3A3-miR-6803-3p) were identified. Among the intersection of progression-associated (carcinogenic) mRNAs and the targets of remission-associated miRNAs, there is a network with miR-132-3p (remission-associated miRNA) located at the core, matched with DICER1, KLHL8, ANKRD12, ASH1L, and IMP4.

Conclusions

Our findings identified altered plasma exosome RNAs among the different groups and between different time points of nCRT, as well as the corresponding enrichments and regulatory networks, which may serve as potentially predictors of treatment response for patients with ESCC after nCRT.

Stanniocalcin 2 (STC2): a universal tumour biomarker and a potential therapeutical target

Stanniocalcin 2 (STC2) is a glycoprotein which is expressed in a broad spectrum of tumour cells and tumour tissues derived from human breast, colorectum, stomach, esophagus, prostate, kidney, liver, bone, ovary, lung and so forth. The expression of STC2 is regulated at both transcriptional and post-transcriptional levels; particularly, STC2 is significantly stimulated under various stress conditions like ER stress, hypoxia and nutrient deprivation. Biologically, STC2 facilitates cells dealing with stress conditions and prevents apoptosis. Importantly, STC2 also promotes the development of acquired resistance to chemo- and radio- therapies. In addition, multiple groups have reported that STC2 overexpression promotes cell proliferation, migration and immune response. Therefore, the overexpression of STC2 is positively correlated with tumour growth, invasion, metastasis and patients' prognosis, highlighting its potential as a biomarker and a therapeutic target. This review focuses on discussing the regulation, biological functions and clinical importance of STC2 in human cancers. Future perspectives in this field will also be discussed.

A novel EZH2/NXPH4/CDKN2A axis is involved in regulating the proliferation and migration of non-small cell lung cancer cells

NXPH4 is discovered to be a neuropeptide-like glycoprotein, belonging to the Neurexophilins (Nxphs) family. NXPH4 shares a similar domain structure with NXPH1, which, however, is poorly understood in terms of its function. Bioinformatics analysis and experimental verification in this study confirmed the abnormal high expression of NXPH4 in non-small cell lung cancer (NSCLC) tissues and cells. Knockdown of NXPH4 by siRNA can inhibit the proliferation and migration of cells, resulting in significant cell cycle arrest in S1 phase. Furthermore, in NSCLC cells, NXPH4 was regulated by transcriptional activation of Enhancer of zeste homolog 2 (EZH2) in its upstream. While downstream, NXPH4 could interact with CDKN2A and downregulate its protein stability, thus participating in the cell cycle regulation through interacting with cyclinD-CDK4/6-pRB-E2F signaling pathway. To sum up, the present study reveals a regulatory pathway of EZH2/NXPH4/CDKN2A in NSCLC, providing possible reference for understanding the function of NXPH4 in tumors.

Identification of colorectal cancer-associated macrophage biomarkers by integrated bioinformatic analysis

The aim of this study was to explore colorectal tumor-associated macrophage (TAM) biomarkers for early diagnosis and surveillance of colorectal cancer (CRC). We used bioinformatic methods to screen array expression data of CRC-related macrophages (GEO: GSE29214) to detect the differentially expressed genes (DEGs) between CRC-related macrophages and normal control cells. We found 431 DEGs in TAMs compared with the control group; 399 were up-regulated and 32 were down-regulated. A functional enrichment analysis showed that the DEGs were involved in positive regulation of the ERK1 and ERK2 cascade, cell activation involved in the immune response, cytokine-mediated signaling pathway, and receptor activity, all of which were significantly enriched. We constructed a protein-protein interaction (PPI) network to identify hub genes. We identified 10 hub genes: ITGB2, ITGAM, C3AR1, PTAFR, C3, CYBB, FCER1G, PLAU, STOM, and GPR84, in the PPI network. We verified the results using array expression data of peripheral blood mononuclear cells (GEO: GSE47756). The results showed that the expression trends of CYBB, PLAU, and STOM were consistent with those found in the GSE29214 dataset. Further verification with The Cancer Genome Atlas and Human Protein Atlas showed that the high expression of PLAU in TAMs was statistically significant (P<0.05). We concluded that PLAU may be a biomarker of CRC-associated macrophages and may have prognostic and predictive significance for clinical utility in CRC management.

Prognostic value of high stanniocalcin 2 expression in solid cancers: A meta-analysis

BACKGROUND

Several studies have explored the prognostic value of stanniocalcin 2 (STC2) in various cancers, but obtained inconsistent results. Therefore, this meta-analysis was performed to determine the prognostic and clinicopathologic significance of STC2 in various cancers.

METHODS

Eligible studies were identified by searching the online databases PubMed, Embase, Web of Science, and the China National Knowledge Infrastructure up to March 2019. Hazard ratios (HRs) with 95% confidence intervals (CIs) and were calculated to clarify the correlation between STC2 expression and prognosis of different cancers. Odds ratios (ORs) with 95% CI were selected to appraise the correlation between STC2 with clinicopathologic characteristics of patients with cancer.

RESULTS

A total of 16 eligible studies with 4074 patients with cancer were included in our meta-analysis. The results showed that high STC2 expression can predict poor overall survival (OS) for cancer (HR = 1.48, 95% CI: 1.15-1.90, P = .002). Subgroup analysis found that high STC2 expression was associated with worse OS in Asian (HR = 1.85, 95% CI: 1.35-2.55), the reported directly from articles group (HR = 1.39, 95% CI: 1.05-1.84), survival curves group (HR = 1.93, 95% CI: 1.36-2.74), and gastric cancer (HR = 1.43, 95% CI: 1.04-1.95). Furthermore, high STC2 expression was significantly related to advanced T stage (OR = 1.83, 95% CI: 1.17-2.86, P = .008), lymph node metastasis (OR = 2.29, 95% CI: 1.51-3.45, P < .001), lymphatic invasion (OR = 2.15, 95% CI: 1.53-3.02, P < .001), venous invasion (OR = 1.97, 95% CI: 1.30-2.99, P = .001), and more advanced clinical stage (OR = 2.36, 95% CI: 1.74-3.19, P < .001) CONCLUSION:: Elevated expression of STC2 suggested a poor prognosis in patients with cancer and may serve as a new tumor marker to monitor cancer development and progression.