SGK3 (CISK) may induce tumor angiogenesis (Hypothesis)

MicroRNAs in Hepatocellular Carcinoma Pathogenesis: Insights into Mechanisms and Therapeutic Opportunities

Hepatocellular carcinoma (HCC) presents a significant global health burden, with alarming statistics revealing its rising incidence and high mortality rates. Despite advances in medical care, HCC treatment remains challenging due to late-stage diagnosis, limited effective therapeutic options, tumor heterogeneity, and drug resistance. MicroRNAs (miRNAs) have attracted substantial attention as key regulators of HCC pathogenesis. These small non-coding RNA molecules play pivotal roles in modulating gene expression, implicated in various cellular processes relevant to cancer development. Understanding the intricate network of miRNA-mediated molecular pathways in HCC is essential for unraveling the complex mechanisms underlying hepatocarcinogenesis and developing novel therapeutic approaches. This manuscript aims to provide a comprehensive review of recent experimental and clinical discoveries regarding the complex role of miRNAs in influencing the key hallmarks of HCC, as well as their promising clinical utility as potential therapeutic targets.

Serum Glucocorticoid-Regulated Kinase-1 in Ischemia-Reperfusion Injury: Blessing or Curse

The family of serum-glucocorticoid-regulated kinase (SGK) consists of three paralogs, SGK-1, SGK-2, and SGK-3, with SGK-1 being the better studied. Indeed, recognition of the role of SGK-1 in regulation of cell survival and proliferation has led to introduction of a number of small-molecule inhibitors for some types of cancer. In addition, SGK-1 regulates major physiologic effects, such as renal solute transport, and contributes to the pathogenesis of non-neoplastic conditions involving major organs including the heart and the kidney. These observations raise the prospect for therapeutic modulation of SGK-1 to reduce the burden of such diseases as myocardial infarction and acute kidney injury. Following a brief description of the structure and function of SGK family of proteins, the present review is primarily focused on our current understanding of the role of SGK-1 in pathologies related to ischemia-reperfusion injury involving several organs (e.g., heart, kidney). The essential role of the mitochondrial permeability transition pore in cell death coupled with the pro-survival function of SGK-1 raise the prospect that its therapeutic modulation could beneficially impact conditions associated with ischemia-reperfusion injury. SIGNIFICANCE STATEMENT: Since the discovery of serum glucocorticoid-regulated kinase (SGK)-1, extensive research has unraveled its role in cancer biology and, thus, its therapeutic targeting. Increasingly, it is also becoming clear that SGK-1 is a major determinant of the outcome of ischemia-reperfusion injury to various organs. Thus, evaluation of existing information should help identify gaps in our current knowledge and also determine whether and how its therapeutic modulation could impact the outcome of ischemia-reperfusion injury.

SGK3 overexpression correlates with a poor prognosis in endoscopically resected superficial esophageal squamous cell neoplasia: A long-term study

BACKGROUND

The expression status of serum and glucocorticoid-induced protein kinase 3 (SGK3) in superficial esophageal squamous cell neoplasia (ESCN) remains unknown.

AIM

To evaluate the SGK3 overexpression rate in ESCN and its influence on the prognosis and outcomes of patients with endoscopic resection.

METHODS

A total of 92 patients who had undergone endoscopic resection for ESCN with more than 8 years of follow-up were enrolled. Immunohistochemistry was used to evaluate SGK3 expression.

RESULTS

SGK3 was overexpressed in 55 (59.8%) patients with ESCN. SGK3 overexpression showed a significant correlation with death (P = 0.031). Overall survival and disease-free survival rates were higher in the normal SGK3 expression group than in the SGK3 overexpression group (P = 0.013 and P = 0.004, respectively). Cox regression analysis models demonstrated that SGK3 overexpression was an independent predictor of poor prognosis in ESCN patients (hazard ratio 4.729; 95% confidence interval: 1.042-21.458).

CONCLUSION

SGK3 overexpression was detected in the majority of patients with endoscopically resected ESCN and was significantly associated with shortened survival. Thus, it might be a new prognostic factor for ESCN.

Contributions of SGK3 to transporter-related diseases

Serum- and glucocorticoid-induced kinase 3 (SGK3), which is ubiquitously expressed in mammals, is regulated by estrogens and androgens. SGK3 is activated by insulin and growth factors through signaling pathways involving phosphatidylinositol-3-kinase (PI3K), 3-phosphoinositide-dependent kinase-1 (PDK-1), and mammalian target of rapamycin complex 2 (mTORC2). Activated SGK3 can activate ion channels (TRPV5/6, SOC, Kv1.3, Kv1.5, Kv7.1, BKCa, Kir2.1, Kir2.2, ENaC, Nav1.5, ClC-2, and ClC Ka), carriers and receptors (Npt2a, Npt2b, NHE3, GluR1, GluR6, SN1, EAAT1, EAAT2, EAAT4, EAAT5, SGLT1, SLC1A5, SLC6A19, SLC6A8, and NaDC1), and Na+/K+-ATPase, promoting the transportation of calcium, phosphorus, sodium, glucose, and neutral amino acids in the kidney and intestine, the absorption of potassium and neutral amino acids in the renal tubules, the transportation of glutamate and glutamine in the nervous system, and the transportation of creatine. SGK3-sensitive transporters contribute to a variety of physiological and pathophysiological processes, such as maintaining calcium and phosphorus homeostasis, hydro-salinity balance and acid-base balance, cell proliferation, muscle action potential, cardiac and neural electrophysiological disturbances, bone density, intestinal nutrition absorption, immune function, and multiple substance metabolism. These processes are related to kidney stones, hypophosphorous rickets, multiple syndromes, arrhythmia, hypertension, heart failure, epilepsy, Alzheimer's disease, amyotrophic lateral sclerosis, glaucoma, ataxia idiopathic deafness, and other diseases.

Risk of Nasopharyngeal Carcinoma Associated with Single Nucleotide Polymorphisms in the MicroRNA Binding Site of SGK3

Objective: Serum/glucocorticoid regulated kinase is a serine/threonine kinase that is involved in regulating cell proliferation, apoptosis, the cell cycle, and ion channel function. The aim of this study was to analyze the relationship between single nucleotide polymorphisms (SNPs) in the microRNA (miRNA) binding site of the SGK3 gene and the risk of nasopharyngeal carcinoma (NPC). Methods: Three SGK3 loci, rs77572541, rs11994200, and rs78158330, were genotyped in 226 NPC patients and 226 healthy controls via Sanger sequencing. Quantitative real-time polymerase chain reaction was used to analyze levels of SGK3 messenger RNA (mRNA), hsa-miR-3529-5p, hsa-miR-379-5p, hsa-miR-498, hsa-miR-4320, and hsa-miR-590-3p. Western blot analysis was used to assess serum and glucocorticoid regulated kinase 3 (SGK3) protein expression. Results: SGK3 rs77572541 locus G allele carriers were 3.47 times more likely to develop NPC than carriers of the A allele (95% confidence interval [CI] = 1.98-6.09, p < 0.01). The SGK3 rs11994200 locus C allele was a major risk factor for NPC (odds ratio = 2.68, 95% CI = 1.63-4.39, p < 0.01). Similarly, carriers of the C allele of the SGK3 rs78158330 locus were 3.36 times more likely to develop NPC than those with the T allele (95% CI = 1.96-5.73, p < 0.01). The SGK3 protein was highly expressed in NPC. The SGK3 rs77572541 locus G allele is the target of hsa-miR-379-5p and hsa-miR-3529-5p, but the A allele is not. The SGK3 rs11994200 locus C allele was the target of hsa-miR-4320, and the G allele was the target of hsa-miR-498. The SGK3 rs78158330 locus T allele was the target of hsa-miR-590-3p. Hsa-miR-3529-5p, hsa-miR-379-5p, and hsa-miR-4320 were down-regulated in NPC tissues (p < 0.01), whereas hsa-miR-498 and hsa-miR-590-3p were highly expressed (p < 0.01). Conclusions: SNPs at the SGK3 loci rs77572541, rs11994200, and rs78158330 are significantly associated with the risk for NPC. These effects may be related to the influence of miRNAs on different alleles, but this needs to be verified both in vitro and in vivo.

LncRNA SNHG5 promotes the progression of osteosarcoma by sponging the miR-212-3p/SGK3 axis

Background

Long non-coding RNA (lncRNA) SNHG5 has been found to play an important role in tumors. Nevertheless, the function and mechanism of lncRNA SNHG5 in osteosarcoma (OS) remains unclear. The purpose of this study was to investigate whether lncRNA SNHG5 can regulate the occurrence and development of OS cells.

Methods

We performed quantitative real time PCR to detect the expression of lncRNA SNHG5 in OS cells. 143B, MG63 (knockdown) and U2OS, U2R (overexpression) cell lines were chosen for the function study of SNHG5. The effect of SNHG5, miR-212-3p, and SGK3 in OS cells was explored by MTT assays, clony formation, flow cytometry, transwell assays, wound healing assays, and cell spreading assays. Quantitative real-time PCR, Western blot analysis and luciferase assays were used to detect the interaction between lncRNA SNHG5 and miR-212-3p.

Results

In this study, knockdown of lncRNA SNHG5 suppressed the growth and metastasis of OS cells, whereas the overexpression of SNHG5 produced an opposite result. Mechanistically, lncRNA SNHG5 functions as a sponger against miR-212-3p and suppresses the miR-212-3p/SGK3 signaling pathway. Introduction of miR-212-3p mimics or inhibitors reverses SNHG5 overexpression or silences the exerted tumor promoting or suppressing effect. In addition, our results showed that the function of SNHG5 can be rescued by miR-212-3p and can regulate the growth and metastasis of OS cells via SGK3, the downstream target of miR-212-3p.

Conclusions

In summary, our study demonstrated that lncRNA SNHG5 can regulate the proliferation and metastasis of OS cells through the miR-212-3p/SGK3 axis. This axis may provide a new target for future clinical treatment.

Electronic supplementary material

The online version of this article (10.1186/s12935-018-0641-9) contains supplementary material, which is available to authorized users.

New Insights into the Genetic Basis of Monge's Disease and Adaptation to High-Altitude

Human high-altitude (HA) adaptation or mal-adaptation is explored to understand the physiology, pathophysiology, and molecular mechanisms that underlie long-term exposure to hypoxia. Here, we report the results of an analysis of the largest whole-genome-sequencing of Chronic Mountain Sickness (CMS) and nonCMS individuals, identified candidate genes and functionally validated these candidates in a genetic model system (Drosophila). We used PreCIOSS algorithm that uses Haplotype Allele Frequency score to separate haplotypes carrying the favored allele from the noncarriers and accordingly, prioritize genes associated with the CMS or nonCMS phenotype. Haplotypes in eleven candidate regions, with SNPs mostly in nonexonic regions, were significantly different between CMS and nonCMS subjects. Closer examination of individual genes in these regions revealed the involvement of previously identified candidates (e.g., SENP1) and also unreported ones SGK3, COPS5, PRDM1, and IFT122 in CMS. Remarkably, in addition to genes like SENP1, SGK3, and COPS5 which are HIF-dependent, our study reveals for the first time HIF-independent gene PRDM1, indicating an involvement of wider, nonHIF pathways in HA adaptation. Finally, we observed that down-regulating orthologs of these genes in Drosophila significantly enhanced their hypoxia tolerance. Taken together, the PreCIOSS algorithm, applied on a large number of genomes, identifies the involvement of both new and previously reported genes in selection sweeps, highlighting the involvement of multiple hypoxia response systems. Since the overwhelming majority of SNPs are in nonexonic (and possibly regulatory) regions, we speculate that adaptation to HA necessitates greater genetic flexibility allowing for transcript variability in response to graded levels of hypoxia.

MicroRNA-144-3p suppresses tumor growth and angiogenesis by targeting SGK3 in hepatocellular carcinoma

In our previous studies, the Illumine Soledad massively parallel signature sequencing of miRNomes in non-tumor and hepatocellular carcinoma (HCC) tissues revealed that microRNA (miR)-144-3p was significantly downregulated in HCC, but its role in HCC development, especially angiogenesis, remains unclear. In this investigation, we found recovering miR-144-3p expression can significantly suppress the growth, migration and induced angiogenic capacity of HCC cells through both in vivo and in vitro experiments. Moreover, clinical correlation analysis showed that low expression of miR-144-3p was positively correlated to poor disease-free survival (DFS) of HCC patients. Mechanistically, serum and glucocorticoid kinase 3 (SGK3), the putative targets of miR-144-3p, was predicted by Target Scan database and identified to be suppressed by miR-144-3p so that inhibiting the activation of mTOR-VEGF downstream signals was activated by the phosphoinositide 3-kinase (PI3K)-independent pathway. Hence, we concluded that miR-144-3p, which is frequently downregulated in HCC, can inhibit proliferation, migration and repress angiogenesis by regulating SGK3 activation with PI3K independent signal pathway, and acts as a prognostic factor for HCC patients.