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

Stanniocalcin 2 is induced by estrogen and promotes growth in endometrial cancer via AMPK pathway

Stanniocalcin 2 (STC2) is identified as a glycosylated peptide hormone and estrogen-responsive gene in cancer cells. STC2 participates in angiogenesis, cell development, cytoprotection, and calcium and phosphate regulation during the development of cancer. The role of STC2 in endometrial cancer (EC) remains unclear. The data from the bioinformatic and immunohistochemical analysis showed that STC2 was upregulated in the EC tissues. The EC cells were treated with 17β-estradiol (E2), and 0.1 μmol/L E2 increased the expression of STC2 in the EC cells. E2 also increased cell viability, promoted proliferation, and inhibited apoptosis of EC. However, the knockdown of STC2 decreased cell viability, reduced proliferation, and promoted apoptosis of E2-stimulated EC. Moreover, silencing of STC2 attenuated E2-induced downregulation of phosphorylated-AMP-activated protein kinase (AMPK) in the EC cells. The loss of STC2 reduced E2-stimulated tumor growth EC in vivo. In conclusion, STC2 deficiency suppressed E2-stimulated proliferation and tumor growth of EC through the activation of AMPK signaling.

The Oncogenic and Diagnostic Potential of Stanniocalcin 2 in Hepatocellular Carcinoma

Purpose

Early detection and prognostic prediction of hepatocellular carcinoma (HCC) remain a great challenge. In this study, we explored the role and diagnostic significance of stanniocalcin 2 (STC2), recently identified as a secretory protein, in HCC.

Methods

STC2 mRNA and protein in HCC tissues were examined by qRT-PCR and immunohistochemistry. The regulatory role of HCC growth by STC2 was evaluated in vitro and in vivo. Serum STC2 levels were determined in HCC patients and compared to those with liver cirrhosis (LC) and normal controls (NC). The difference and significance of STC2 levels between groups were analyzed by Mann–Whitney U-test. The diagnostic value of serum STC2 in detecting early HCC was assayed with receiver operating characteristics (ROC). The association of STC2 with overall survival (OS) was determined with Kaplan–Meier method.

Results

STC2 was elevated in about 77.1% HCC patients and correlated with advanced tumor progression. Overexpression or knockdown of STC2 stimulated or suppressed HCC colony formation and xenograft tumor growth. AKT activation played a critical role in tumor-promoting effect of STC2. The median level of serum STC2 in HCC patients (n = 98, 2086.6 ng/L) was 2.6-fold and 4.2-fold that in LC patients (n = 42, 801.9 ng/L) and NC (n = 26, 496.9 ng/L), respectively. A cut-off value 1493 ng/L for STC2 could distinguish early HCC from LC with a sensitivity of 76.9% and a specificity of 76.2%, both of which were superior to AFP at 20 μg/L (sensitivity 69.2%, specificity 52.4%). STC2 was positive in 77.8% (14/18) AFP-negative patients. High STC2 level was correlated with poor overall and disease specific survival.

Conclusion

STC2 is upregulated in both tumor and serum of HCC patients, and its overexpression promotes HCC via AKT pathway. STC2 possesses a diagnostic significance and may serve as an auxiliary biomarker of AFP for detecting early HCC.

Prognostic value of STC1 in solid tumors: a meta-analysis

Aim: The prognostic value of STC1 has been evaluated in solid tumors. However, the results remain controversial. Materials & methods: Relevant studies published up to 27 February 2021 were identified by a comprehensive search of the PubMed, EMBASE and Web of Science databases. Hazard ratios (HRs) and odds ratios with 95% CIs were applied to explore the association between STC1 and survival outcome and clinical characteristics. Results: Sixteen articles involving 2942 participants were included in this meta-analysis. The pooled analysis showed that high STC1 expression was significantly associated with worse overall survival (HR: 1.91; 95% CI: 1.63-2.24) and disease-free survival/progression-free survival/relapse-free survival (HR: 2.01; 95% CI: 1.34-3.02). Conclusion: STC1 may be an effective prognostic marker in solid tumors.

Prognostic Value of Peroxiredoxin-1 Expression in Patients with Solid Tumors: a Meta-Analysis of Cohort Study

Methods

We comprehensively searched electronic databases, namely, PubMed, Web of Science, EMBASE, Chinese National Knowledge Infrastructure (CNKI), and WanFang databases up to December 2019. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated to evaluate the association between PRDX1 protein expression and the survival of patients with solid tumors. Odds ratios (ORs) with 95% CIs were pooled to estimate the correlation between PRDX1 protein expression and clinicopathologic characteristics in the patients.

Results

Seventeen cohort studies that involved 2,858 patients were included in this meta-analysis. The pooled results indicated that positive PRDX1 expression was related to poor overall survival (HR = 1.68, 95% CI: 1.24-2.27, P = 0.001) and disease-free survival (HR = 1.88, 95% CI: 1.31-2.70, P = 0.001). In addition, high PRDX1 expression was associated with large tumor size (OR = 1.69, 95% CI: 1.07-2.68, P = 0.025), advanced TNM stage (OR = 2.26, 95% CI: 1.24-4.13, P = 0.008), and poor tumor differentiation (OR = 0.59, 95% CI: 0.44-0.81, P = 0.001).

Conclusions

PRDX1 overexpression is associated with poor outcomes of cancers and may serve as a prognostic biomarker for malignant patients. Hence, PRDX1 could be a new target for antitumor therapy.

Stanniocalcin 2 contributes to aggressiveness and is a prognostic marker for oral squamous cell carcinoma

Stanniocalcin 2 (STC2), a glycoprotein that regulates calcium and phosphate homeostasis during mineral metabolism, appears to display multiple roles in tumorigenesis and cancer progression. This study aimed to access the prognostic value of STC2 in oral squamous cell carcinoma (OSCC) and its implications in oral tumorigenesis. STC2 expression was examined in 2 independent cohorts of OSCC tissues by immunohistochemistry. A loss-of-function strategy using shRNA targeting STC2 was employed to investigate STC2 in vitro effects on proliferation, apoptosis, migration, invasion, epithelial-mesenchymal transition (EMT) and possible activation of signaling pathways. Moreover, STC2 effects were assessed in vivo in a xenograft mouse cancer model. High expression of STC2 was significantly associated with poor disease-specific survival (HR: 2.67, 95% CI: 1.37-5.21, p = 0.001) and high rate of recurrence with a hazard ratio of 2.80 (95% CI: 1.07-5.71, p = 0.03). In vitro downregulation of STC2 expression in OSCC cells attenuated proliferation, migration and invasiveness while increased apoptotic rates. In addition, the STC2 downregulation controlled EMT phenotype of OSCC cells, with regulation on E-cadherin, vimentin, Snail1, Twist and Zeb2. The reactivation of STC2 was observed in the STC2 knockdown cells in the in vivo xenograft model, and no influence on tumor growth was observed. Modulation of STC2 expression levels did not alter consistently the phosphorylation status of CREB, ERK, JNK, p38, p70 S6K, STAT3, STAT5A/B and AKT. Our findings suggest that STC2 overexpression is an independent marker of OSCC outcome and may contribute to tumor progression via regulation of proliferation, survival and invasiveness of OSCC cells.

Deimination Protein Profiles in Alligator mississippiensis Reveal Plasma and Extracellular Vesicle-Specific Signatures Relating to Immunity, Metabolic Function, and Gene Regulation

Alligators are crocodilians and among few species that endured the Cretaceous-Paleogene extinction event. With long life spans, low metabolic rates, unusual immunological characteristics, including strong antibacterial and antiviral ability, and cancer resistance, crocodilians may hold information for molecular pathways underlying such physiological traits. Peptidylarginine deiminases (PADs) are a group of calcium-activated enzymes that cause posttranslational protein deimination/citrullination in a range of target proteins contributing to protein moonlighting functions in health and disease. PADs are phylogenetically conserved and are also a key regulator of extracellular vesicle (EV) release, a critical part of cellular communication. As little is known about PAD-mediated mechanisms in reptile immunology, this study was aimed at profiling EVs and protein deimination in Alligator mississippiensis. Alligator plasma EVs were found to be polydispersed in a 50-400-nm size range. Key immune, metabolic, and gene regulatory proteins were identified to be posttranslationally deiminated in plasma and plasma EVs, with some overlapping hits, while some were unique to either plasma or plasma EVs. In whole plasma, 112 target proteins were identified to be deiminated, while 77 proteins were found as deiminated protein hits in plasma EVs, whereof 31 were specific for EVs only, including proteins specific for gene regulatory functions (e.g., histones). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed KEGG pathways specific to deiminated proteins in whole plasma related to adipocytokine signaling, while KEGG pathways of deiminated proteins specific to EVs included ribosome, biosynthesis of amino acids, and glycolysis/gluconeogenesis pathways as well as core histones. This highlights roles for EV-mediated export of deiminated protein cargo with roles in metabolism and gene regulation, also related to cancer. The identification of posttranslational deimination and EV-mediated communication in alligator plasma revealed here contributes to current understanding of protein moonlighting functions and EV-mediated communication in these ancient reptiles, providing novel insight into their unusual immune systems and physiological traits. In addition, our findings may shed light on pathways underlying cancer resistance, antibacterial and antiviral resistance, with translatable value to human pathologies.