Stanniocalcin-1 Gene Research Articles

STC2 Inhibits Hepatic Lipid Synthesis and Correlates with Intramuscular Fatty Acid Composition, Body Weight and Carcass Traits in Chickens

Stanniocalcin 2 (STC2) is a secreted glycoprotein involved in multiple biological processes. To systemically study the biological role of STC2 in chickens, phylogenetic tree analysis and conservation analysis were conducted. Association analysis between variations in the STC2 gene and the economic traits of Gushi-Anka F2 was conducted. The tissue expression patterns of STC2 expression in different chicken tissues and liver at different stages were detected. The biological role of STC2 in chicken liver was investigated through overexpression and interfering methods in the LMH cell line. Correlation analyses between STC2 expression and lipid components were conducted. (1) The phylogenetic tree displayed that chicken STC2 is most closely related with Japanese quail and most distantly related with Xenopus tropicalis. STC2 has the same identical conserved motifs as other species. (2) rs9949205 (T > C) found in STC2 intron was highly significantly correlated with chicken body weight at 0, 2, 4, 6, 8, 10 and 12 weeks (p < 0.01). Extremely significant correlations of rs9949205 with semi-evisceration weight (SEW), evisceration weight (EW), breast muscle weight (BMW), leg muscle weight (LMW), liver weight and abdominal fat weight (AFW) were revealed (p < 0.01). Significant associations between rs9949205 and abdominal fat percentage, liver weight rate, breast muscle weight rate and leg muscle weight rate were also found (p < 0.05). Individuals with TT or TC genotypes had significantly lower abdominal fat percentage and liver weight rate compared to those with the CC genotype, while their body weight and other carcass traits were higher. (3) STC2 showed a high expression level in chicken liver tissue, which significantly increased with the progression of age (p < 0.05). STC2 was observed to inhibit the content of lipid droplets, triglycerides (TG) and cholesterol (TC), as well the expression level of genes related to lipid metabolism in LMH cells. (4) Correlation analysis showed that the STC2 gene was significantly correlated with 176 lipids in the breast muscle (p < 0.05) and mainly enriched in omega-3 and omega-6 unsaturated fatty acids. In conclusion, the STC2 gene in chicken might potentially play a crucial role in chicken growth and development, as well as liver lipid metabolism and muscle lipid deposition. This study provides a scientific foundation for further investigation into the regulatory mechanism of the STC2 gene on lipid metabolism and deposition in chicken liver.

Evaluating STC2 gene RNA in peripheral blood serum of gastric cancer patients.

Cancer is one of the leading causes of death in the world. Invasive microscopic and endoscopic methods are not suitable for routine screening of gastric cancer. Therefore, the need for biomarkers that can detect quickly, efficiently, and with high sensitivity in the early stages of cancer is strongly felt. Stanniocalcin plays a role in regulating calcium and phosphorus in the body. In addition, it plays a role in neuron cell differentiation, angiogenesis, wound healing, fertility and embryo development, and cancer. This study investigated the level of expression of the Stanniocalcin 2 (STC2) gene in the serum of patients with gastric cancer. This case-control study was conducted on the samples of 60 patients with gastric cancer (cases) and 60 healthy individuals (controls). Peripheral blood samples from gastric cancer patients and volunteers as control groups were collected in tubes containing EDTA anticoagulant and were immediately subjected to serum separation. After centrifugation, serum RNA was extracted, and after cDNA synthesis, STC2 gene serum RNA level was measured by the Taq Man method and Real-time PCR using specific primers and probes. Then, the results of serum evaluations and clinicopathological information of patients and control group were collected along with the information obtained from reviewing patients' files and demographic findings, regulatory tables, and related charts. SPSS22 software was used to analyze descriptive data. According to the study results, the high expression of the STC2 gene was 31 cases in the case group and 13 cases in the control group. However, there was a significant relationship between the high expression of the STC2 gene and gastric cancer (p = 0.0001). However, there was no significant relationship between the gender of patients and high expression of the STC2 gene. However, the age of 35% of the patients was more than 65 years, and there was a significant relationship between the age of the patients and the high expression of the STC2 gene (P = 0.028). Although there was no significant relationship between the anatomical location of the cancer and the subtypes of the cancer and the high expression of the STC2 gene, there was a significant relationship between the degree of cancer differentiation and the high expression of STC2 gene (P<0.05). In general, STC2 can be used as a biomarker to determine the border and margins of the tumor. Analysis of STC2 gene expression during surgery can reduce surgical error in tumor removal and increase the success of surgery for tumor removal.

Molecular cloning and characterization of STC1 gene and its functional analyses in yak (Bos grunniens) cumulus granulosa cells

Cumulus granulosa cells (CGCs), an important type of ovarian somatic cells, carries out various functions related to oogenesis, follicular development, and steroidogenesis. Studying the biological mechanisms involved in the development and function of CGCs makes a great contribution to understanding the reproductive regulation in female animals. Stanniocalcin-1 (STC1) is an important Ca2+-regulated glycoprotein hormone that exhibits high expression levels in ovaries. In this study, we cloned the coding sequence of the yak STC1, predicted the structure of STC1 protein, detected the expression and localization of STC1 in yak ovaries, and analyzed the functions of STC1 in yak CGCs. The CDS (coding sequence) region of yak STC1 gene was found to be 744 bp and encoded 247 amino acids. Homology comparison revealed that STC1 protein was highly conserved among mammals. The STC1 mRNA displayed dynamic expression profiles in different stages of yak ovaries, and the highest expression was found in the follicular phase. Regarding localization, STC1 protein was widely distributed in various kinds of yak ovarian cells, including oocytes, mural granulosa cells, CGCs, and thecal cells. Repressing the expression of STC1 resulted in defective proliferation and survival of yak CGCs. In addition, knockdown the expression of STC1 repressed the secretion of progesterone and promoted the secretion of estrogen. Overexpression of STC1 partially rescued the proliferation of CGCs and resulted in opposite effects on the secretion of progesterone and estrogen. Several apoptosis and steroidogenesis-related genes, including BAX, BCL2, HSD3B1, HSD17B1, CYP11A1 and CYP17A1 showed altered expressions after repressing or increasing the expression of STC1 in yak CGCs. To the best of our knowledge, this study is the first to focus on the role of STC1 in yak CGCs, and the outcomes offer fresh insights into the mechanism governing yak reproduction.

Abstract 888: Elucidating the mechanisms of eATP-induced changes in cell growth, energy metabolism, and cancer stem cells in human non-small lung cancer A549 cells

Abstract The tumor microenvironment (TME) has concentrations of extracellular ATP (eATP) 103-104 times higher than normal healthy tissues, implying that eATP may have important roles in tumor development and progression. Our previous study, cited by a Nature Reviews Cancer paper, showed that the extracellular ATP (eATP) is internalized by tumors via macropinocytosis, a type of endocytosis, to increase intracellular ATP (iATP) levels and support tumor cells growth, drug resistance, and cancer cell movement by initiating epithelial to mesenchymal transition (EMT). Recently, our lab found that eATP functions in promoting cancer cell growth, metastasis are similar to those of TGF-β, a well-known EMT and cancer stem cells (CSCs) inducer. Increasing reports state that the EMT and CSCs share some molecular links, but the detailed mechanisms and inductor of them are still far from clear. In this report, eATP’s function in CSCs induction was investigated first. Result shows that eATP treatment significantly induces the protein expression level of CSC related makers, increases cell colony numbers, and cell populations with CSC markers expressed in human lung cancer A549 cells. In addition, RNA-sequencing analysis reveals the gene Stanniocalcin 1 (STC1) is significantly upregulated in both eATP and TGF-β treatments. STC1 gene has been reported to be a competitive biomarker in the tracking of cancers’ progressing. Besides, STC1 exhibits concentration-dependent stimulation effects on electron transportation chain (ETC) and respiration. However, the detail function of STC1 gene in eATP induced cell growth is unknown. To find out the mechanism, CRISPR-Cas9 technique was used to generate STC1 gene targeted knockout (STC1 KO) A549 cells. STC1 KO cells show slower cell growth rate, lower intracellular ATP level and lower oxygen consumption rate (OCR) when compared with normal A549 cells in vitro. These results strongly indicate STC1 gene involved in eATP induced cell growth by alteration iATP level and metabolic profile. Overall, this study not only unravels new role of eATP in CSC induction, but also provides new mechanism of eATP induced cell growth by altering the protein expression level of STC1. Citation Format: Jingwen Song, Xiaozhuo Chen. Elucidating the mechanisms of eATP-induced changes in cell growth, energy metabolism, and cancer stem cells in human non-small lung cancer A549 cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 888.

Effect of the Porcine STC-1 Gene on Autophagy and Mitochondrial Function as Induced by Serum Starvation.

Stanniocalcin-1 (STC-1) is a glycoprotein hormone involved in calcium/phosphorus metabolism and direct inhibition of bone and muscle growth. The aim of this study was to investigate the STC-1 gene with respect to the regulatory mechanisms of porcine growth metabolic pathways involving autophagy. Western blotting was used to detect the expression of autophagy and mitochondrial function-related proteins, and flow cytometry was used to detect mitochondrial function-related. Changes in the autophagosome and mitochondrial were observed by electron microscopy. The expression of the autophagy-related proteins was detected by confocal microscopy. The results showed that Pink1, Parkin and LC3B expression was increased; SQSTM1/P62 expression was reduced. Electron microscopy revealed that the cells in the serum starvation group all produced autophagosomes. The fluorescence intensity of GFP-LC3B and GFP-Parkin increased. The Bax/Bcl-2 ratio, Pink1 and Parkin protein levels were profoundly reduced in the STC-KO. In addition, the increase in Mfn2, OPA1, DRP1 and LC3B proteins was attenuated; the increase in the apoptosis rate and amount of active oxygen was attenuated; the decrease in membrane potential; the decrease in ATP was reversed; the fluorescence intensity of GFP-LC3B and GFP-Parkin was increased. These results indicate that autophagy can be caused by serum starvation. Knocking out the porcine STC-1 gene had an obvious antiapoptotic effect on cells, the inhibition of serum starvation-induced autophagy. This is the first study to show that the porcine STC-1 gene confers self-protection in the absence of nutrients. To provide a theoretical basis for studying the effect of STC-1 on pig growth and development.

Antioncogenic Effect of MicroRNA-206 on Neck Squamous Cell Carcinoma Through Inhibition of Proliferation and Promotion of Apoptosis and Autophagy.

Recent studies have reported the crucial role of stanniocalcin-2 (STC2) in hepatocellular carcinoma; however, its role in head and neck squamous cell carcinoma (HNSCC) remains elusive. In this study, microRNA-206 (miR-206) was predicted to target STC2 gene. The study herein aimed to elucidate the effect of miR-206 on HNSCC by targeting STC2. STC2 was highly expressed in HNSCC tissues and cells. By targeting STC2, miR-206 decreased mRNA and protein expression of STC2. Importantly, our study showed that miR-206 blocked the Akt signaling pathway by inhibiting STC2. Intriguingly, our data from in vitro and in vivo experiments suggested that miR-206 overexpression led to decreased cell proliferation and increased cell apoptosis and autophagy, as well as suppressed tumor growth; whereas, STC2 silencing reversed the effects of miR-206 inhibitor on those biological behaviors. In this study, we investigated the antioncogenic effect of miR-206 on HNSCC by targeting STC2, and highlighted miR-206/STC2 aixs as potential therapeutic targets for HNSCC.

Expression of Stanniocalcin 2 in Breast Cancer and Its Clinical Significance.

This study aims to explore the expression of stanniocalcin 2 (STC2) gene in breast cancer and its clinical significance. Female patients with breast cancer from Zhongnan Hospital of Wuhan University admitted during March 2014 to October 2014 were enrolled in this study. All the tissues used in this experiment included 50 cases of breast cancer tissues and corresponding 50 cases of paracancer normal breast tissues with complete patients' information. The real-time quantitative polymerase chain reaction (qPCR) was applied to detect the expression of STC2 gene in 50 cases of breast cancer and paracancer normal breast tissues. The results showed that the expression level of STC2 gene in 50 cases of breast cancer tissues was significantly higher than that in paracancer normal breast tissues (P&lt;0.001). The expression of STC2 gene was correlated with lymph node metastasis, distant metastasis, TNM stage and histological grade (P&lt;0.001). The expression level of STC2 gene was significantly higher in breast cancer tissues with higher expression of Ki-67 (P&lt;0.001). The expression level of STC2 gene was significantly higher in estrogen receptor (ER) positive breast cancer tissues than in ER negative ones (P&lt;0.001). However, different groups of age, pathological type, tumor size, PR expression and human epidermal growth factor receptor-2 (HER2) expression did not show significant differences in STC2 expression (P&gt;0.05). In conclusion, the abnormal overexpression of STC2 gene may play a role in the development and progression of breast cancer, and it can be used as an independent metastasis and prognostic factor of breast cancer. In addition, STC2 gene probably promotes the development and metastasis of breast cancer by interacting with estrogen and ER, and it may become a new direction for breast cancer endocrine therapy.

21: Mesenchymal Stem Cells Alleviated Palmitic Acid Induced Endothelial to Mesenchymal Transition in HUVEC by Secreting STC1

Background: Endothelial dysfunction (ED) is an early indicator of vascular complications in type 2 diabetes. Hyperlipidemia is believed to be a key causal factor promoting ED. Our previous study showed that mesenchymal stem cells (MSCs) were able to ameliorate palmitic acid (PA) induced ED, but the mechanisms involved are unclear. Endothelial-to-mesenchymal transition (EndMT) is demonstrated mechanistically related to ED in a variety of vascular diseases. Here we explored the effects of MSCs on PA induced EndMT and disclosed the mechanism in human umbilical vein endothelial cells (HUVECs). Methods: The primary HUVECs were treated by PA (50 μM) with or without human umbilical cord derived MSCs (UC-MSCs) for 24 h in Transwell system at a ratio of 5:1. EndMT related proteins expression were evaluated by western blot and immunofluorescence. The secretion of stanniocalcin 1 (STC1) was quantified using an ELISA kit. Recombinant STC1 (rSTC1) and siRNA targeting STC1 were used to evaluate the role of STC1 in MSCs mediated protective effects. Result: After PA treatment, the cell morphology of HUVECs changed from an endothelial-typical cobblestone-like appearance to a mesenchymal-typical spindle-shaped pattern, suggesting the occurrence of EndMT. However, coculture with MSCs alleviated the morphological change of HUVECs (Fig.1A). Western blot analysis revealed that PA significantly decreased endothelial marker CD31 and CD144 expression and increased fibroblast markers vimentin and α-SMA expression, which could be partly reversed by coculture with MSCs (Fig.B). Consistently, immunofluorescent staining for CD31 and α-SMA revealed a significant loss of CD31 and enhancement of α-SMA in PA group in comparison of control. However, MSCs effectively antagonized PA induced toxicity by increasing CD31 and decreasing α-SMA expression in HUVECs (Fig.1C). Next, we explored the underlying mechanisms focusing on the secretome of MSCs. We found that resting MSCs secreted more STC1 than HUVECs did, while, PA (50 μM) strongly stimulated MSCs to synthesize and release much more STC1 (Fig.2A). Furthermore, the cell viability of HUVECs declined to 49% of control after PA stimulation. However, the addition of rSTC1 showed similar protective effect of MSCs, and restored the cell viability to 89% (Fig.2B). rSTC1 also reversed the expression switch of EndMT- related proteins (Fig.2C). Additionally, silencing of STC1 gene by siRNA in MSCs abrogated above protective effects suggesting the critical role of STC1 in MSCs (Fig.2D-E). Conclusion: MSCs ameliorated PA-induced EndMT in HUVECs, in which the STC1 secreted by MSCs has played a critical role. National Natural Science Foundation of China (grant number 31571474 and 81370824).

The effect of STC1 gene on radiosensitivity of human lung cancer A549 cell line

Objective To investigate effect of stanniocalcin-1(STC1) gene on the proliferation, apoptosis and radiotherapy sensitivity of non-small cell lung cancer. Methods The STC1 siRNA (STC1-siRNA) and the non-interfering siRNA (negative control group) were transfected into the human lung cancer A549 cells by Lipofectamine™2000, and the blank control group was established. The expression level of STC1 protein was detected after transfection for 48 h by Western blotting. Clone forming test was adopted to detect the proliferation of A549 cells after STC1-siRNA and irradiation treatment. CCK8 assay was performed to detect the cell viability after treatment with STC1-siRNA and STC1-siRNA+ 8 Gy. The cell apoptosis was detected by flow cytometry. The expression levels of Ki67, Bax, STAT3 and p-STAT3 proteins were quantitatively measured by Western blotting. Results The expression level of STC1 protein in the A549 cells transfected with STC1-siRNA was significantly down-regulated than that in the blank control group (P<0.05). Compared with the blank control group, the sensitization ratio was significantly enhanced after STC1-siRNA transfection. Compared with the blank control group, the cell viability and the expression levels of Ki67 and p-STAT3 protein were significantly decreased, whereas the apoptosis rate and the expression of Bax protein were significantly increased in the STC1-siRNA group. Compared with the STC1-siRNA group, the cell viability and the expression levels of Ki67 and p-STAT3 proteins were significantly decreased, whereas the cell apoptosis rate and the expression of Bax protein were remarkably increased in the STC1-siRNA+ 8 Gy group (all P<0.05). Conclusion Inhibition of STC1 gene expression can enhance the radiotherapy sensitivity and down-regulate the STAT3 signaling pathway in non-small cell lung cancer. Key words: STC1 gene; Non-small cell lung cancer; Radiosensitivity; STAT3 signaling pathway

Effect of STC2 gene silencing on colorectal cancer cells.

Stanniocalcin 2 (STC2), a secretory glycoprotein hormone, regulates many biological processes including cell proliferation, apoptosis, tumorigenesis and atherosclerosis. However, the effect of STC2 on proliferation, migration and epithelial-mesenchymal transition (EMT) progression in human colorectal cancer (CRC) cells remains poorly understood. The expression level of STC2 was determined by quantitative real-time polymerase chain reaction (qPCR) and western blot analysis. Cell Counting Kit-8 (CCK-8) was used to detect the viability of SW480 cells. The invasion and migration of cells were identified by wound healing and Transwell assays. The mRNA and protein expression levels of β-catenin, matrix metalloproteinase (MMP)-2, MMP-9, E-cadherin and vimentin were assessed by qPCR and western blot analysis. In the present study, it was demonstrated that STC2 was highly expressed in the CRC cell lines. After silencing of STC2, the cell viability, migration and invasion were significantly reduced. Silencing of STC2 in the CRC Sw480 cells increased the expression of E-cadherin and decreased the expression of vimentin, MMP-2 and MMP-9, compared to those in the normal and empty vector group. Furthermore, the expression of β-catenin in the STC2 gene silenced group was suppressed, and the expression of β-catenin was reversed by Wnt activator, SB216763. These results demonstrated that STC2 participates in the development and progression of CRC by promoting CRC cell proliferation, survival and migration and activating the Wnt/β-catenin signaling pathway.

Identification of novel polymorphism in buffalo stanniocalcin-1 gene and its expression analysis in mammary gland under different stages of lactation

Stanniocalcin-1 (STC1) is secreted by the variety of tissues having a major role in the regulation of calcium ions in the involuting mammary gland. The present work aims to sequence and structural characterization as well as expression profiling of STC1 gene in buffalo. Polymorphism identified in the 3-untranslated region (UTR) was analysed by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) genotyping in riverine and swamp buffaloes. Expression profiling of STC1 was performed in different lactation stages of mammary gland and peripheral blood mononuclear cells to study the impact of 3'-UTR polymorphism on its expression. Different polymorphic sites were detected in the entire coding and noncoding regions of riverine and swamp buffaloes, including two INDELs. An identified polymorphic nucleotide locus A324G, having target sites for two miRNAs, namely bta-miR-2382 and bta-miR-1343, reported in cattle, was genotyped by PCR-RFLP to reveal variable allelic distribution among swamp and riverine buffaloes. Gene expression profiling across buffalo mammary tissues representing different lactation stages showed maximum expression of the STC1 gene in the involuting mammary gland. Ruminants' specific genetic variation has been observed in STC1 and its implication in buffalo mammary gland involution as well as coregulation of gene expression through miRNA binding in the 3'-UTR is suggested.

Stanniocalcin 2 expression is associated with a favourable outcome in male breast cancer

Breast cancer can occur in either gender; however, it is rare in men, accounting for <1% of diagnosed cases. In a previous transcriptomic screen of male breast cancer (MBC) and female breast cancer (FBC) occurrences, we observed that Stanniocalcin 2 (STC2) was overexpressed in the former. The aim of this study was to confirm the expression of STC2 in MBC and to investigate whether this had an impact on patient prognosis. Following an earlier transcriptomic screen, STC2 gene expression was confirmed by RT‐qPCR in matched MBC and FBC samples as well as in tumour‐associated fibroblasts derived from each gender. Subsequently, STC2 protein expression was examined immunohistochemically in tissue microarrays containing 477 MBC cases. Cumulative survival probabilities were calculated using the Kaplan–Meier method and multivariate survival analysis was performed using the Cox hazard model. Gender‐specific STC2 gene expression showed a 5.6‐fold upregulation of STC2 transcripts in MBC, also supported by data deposited in Oncomine™. STC2 protein expression was a positive prognostic factor for disease‐free survival (DFS; Log‐rank; total p = 0.035, HR = 0.49; tumour cells p = 0.017, HR = 0.44; stroma p = 0.030, HR = 0.48) but had no significant impact on overall survival (Log‐rank; total p = 0.23, HR = 0.71; tumour cells p = 0.069, HR = 0.59; stroma p = 0.650, HR = 0.87). Importantly, multivariate analysis adjusted for patient age at diagnosis, node staging, tumour size, ER, and PR status revealed that total STC2 expression as well as expression in tumour cells was an independent prognostic factor for DFS (Cox regression; p = 0.018, HR = 0.983; p = 0.015, HR = 0.984, respectively). In conclusion, STC2 expression is abundant in MBC where it is an independent prognostic factor for DFS.

PO-319 Role of stanniocalcin-1 on macrophage differentiation and cytokine production

IntroductionInflammation is one of the cancer hallmarks that promotes tumour formation. The infiltration of immune cells is linked to the growth and metastasis of various types of solid tumours. Clinical and experimental data indicate that cancer tissues with high infiltration of tumor-associated macrophages (TAMs) are associated with poor prognosis and resistance to therapeutics. Therefore, an understanding on the factors responsible for macrophage-homing and differentiation of M1 and M2 TAMs is recognised to be an important immunotherapeutic strategy. Stanniocalcin-1 (STC1) is a paracrine factor associated with inflammation and carcinogenesis. Recent evidences suggested the roles of STC1 on anti-inflammation and alteration of macrophage functions. However, the role of STC1 in macrophage differentiation is not clear. With the benefit of hindsight, we hypothesised that STC1 may play a role in differentiation and inflammatory functions of macrophages.Material and methodsHuman Leukaemia cells (THP-1) were differentiated into macrophages by 5 nM phorbol 12-myristate 13-acetate (PMA) for 6 hour, followed by directed M1 or M2 polarisation, induced by additional treatment with ‘IFNγ+LPS’, or ‘IL-4+IL-13’ respectively for another 18 hour incubation. To generate STC1 gene knockdown on THP-1, ON-TARGET Human STC1 siRNA was used. Cells were treated with siRNA/Lipofectamine complex before differentiation-treatments.Results and discussionsTranscript levels of macrophage (M1 and M2) markers and STC1 were significantly upregulated by PMA. An intermitted removal of PMA significantly abolished the upregulation of STC1 and TNFα (M1-marker) but not M2-markers (e.g. CD163). This suggested that STC1 was not a determining factor on differentiation but might play a supporting function in the process, especially in M1 polarisation. Drug-induced M1 differentiation remarkably upregulated mRNA levels of M1-markers and STC1 as compared with M2 differentiation. Intriguingly, STC1-knockdown before differentiation and M1 polarisation caused significant inductions of M1-marker transcripts, but no significant effects on M2-polarised macrophages. This suggested STC1 induction acts to counteract M1 cytokine production.ConclusionThe present study demonstrated the involvement of STC1 in the process of macrophage differentiation, particularly in suppressing the expression levels of pro-inflammatory cytokines. The characterisation of STC1 in the functionality of macrophages can provide insight into its role in TAMs.

Stanniocalcin-1 Hormone in Nonpreeclamptic and Preeclamptic Pregnancy: Clinical, Life-Style, and Genetic Modulators.

Context and Objectives:The study represents the first comprehensive analysis of Stanniocalcin-1 (STC1) hormone in human pregnancy, assessing clinical, lifestyle, and genetic determinants of circulating STC1 at term.Design, Setting, and Participants:Participants included women with (n = 50) and without (n = 316) preeclampsia (PE) at delivery, recruited in the REPROgrammed fetal and/or maternal METAbolism (REPROMETA) study (2006–2011, Estonia). Genetic association analysis combined PE cases (n = 597) and controls (n = 623) from the REPROMETA and Finnish Genetics of Preeclampsia Consortium (2008–2011) studies.Main Outcome Measure(s):Maternal postpartum plasma STC1 was measured by ELISA (n = 366) and placental STC1 gene expression by TaqMan quantitative RT-PCR (n = 120). Genotyping was performed using Sequenom MassArray.Results:Significantly higher STC1 plasma level was measured for the PE (median, 1952 pg/mL; 1030–4284 pg/mL) compared with non-PE group (median, 1562 pg/mL; 423–3781 pg/mL; P = 3.7 × 10−4, Mann-Whitney U test). Statistical significance was enhanced after adjustment for cofactors (linear regression, P = 1.8 × 10−6). STC1 measurements were negatively correlated with maternal smoking. Prepregnancy body mass index had a positive correlation with STC1 only among PE patients (r = 0.45; P = .001). The strongest genetic association with hormone concentrations was detected for STC1 single nucleotide polymorphisms rs3758089 (C allele: minor allele frequency, 5%; linear regression: β = 249.2 pg/mL; P = .014) and rs12678447 (G allele: minor allele frequency, 7%; β = 147.0 pg/mL; P = .082). rs12678447 placental genotypes were significantly associated with STC1 gene expression (P = .014). The REPROMETA/Finnish Genetics of Preeclampsia Consortium meta-analysis suggested an increased risk to develop late-onset PE for the rs12678447 G allele carriers (P = .05; odds ratio = 1.38 [0.98–1.93]).Conclusions:Increased STC1 hormone represents a hallmark of late-onset PE. STC1 gene variants modulate placental gene expression and maternal hormone levels.

Stanniocalcin 2 enhances mesenchymal stem cell survival by suppressing oxidative stress.

To overcome the disadvantages of stem cell-based cell therapy like low cell survival at the disease site, we used stanniocalcin 2 (STC2), a family of secreted glycoprotein hormones that function to inhibit apoptosis and oxidative damage and to induce proliferation. STC2 gene was transfected into two kinds of stem cells to prolong cell survival and protect the cells from the damage by oxidative stress. The stem cells expressing STC2 exhibited increased cell viability and improved cell survival as well as elevated expression of the pluripotency and self-renewal markers (Oct4 and Nanog) under sub-lethal oxidative conditions. Up-regulation of CDK2 and CDK4 and down-regulation of cell cycle inhibitors p16 and p21 were observed after the delivery of STC2. Furthermore, STC2 transduction activated pAKT and pERK 1/2 signal pathways. Taken together, the STC2 can be used to enhance cell survival and maintain long-term stemness in therapeutic use of stem cells. [BMB Reports 2015; 48(12): 702-707]

Stanniocalcin1 gene expression in patients with acute leukemia: impact on response to therapy and disease outcome.

Stanniocalcin1 (STC1) is a hormone that regulates cell growth and survival; this study aimed to evaluate the STC1 gene expression in patients with acute leukemia and assess its prognostic significance. Seventy-six patients with acute leukemia were enrolled for determination of mRNA STC1 by real-time quantitative polymerase chain reaction at diagnosis and at day 28. Median STC1 gene expression was 16.2 and 4.43 in patients with acute myeloid leukemia and 9.67 and 2.37 in patients with acute lymphoblastic leukemia on days 0 and 28, respectively. A cutoff level for STC1 gene expression was established subdividing patients into high- and low-STC1 gene expression groups. Median STC1 gene expression at days 0 and 28 was significantly higher among patients who were nonresponders to therapy than among those who were therapy responders in both groups. Patients achieving complete remission had significantly lower baseline STC1 gene expression than those in relapse. High STC1 gene expression was associated with shorter overall and disease-free survival times. STC1 gene expression at diagnosis might be a useful prognostic marker for clinical outcome and monitoring therapeutic response in patients with acute leukemia.

Spatiotemporal proliferation of human stromal cells adjusts to nutrient availability and leads to stanniocalcin-1 expression in vitro and in vivo

Cells and tissues are intrinsically adapted to molecular gradients and use them to maintain or change their activity. The effect of such gradients is particularly important for cell populations that have an intrinsic capacity to differentiate into multiple cell lineages, such as bone marrow derived mesenchymal stromal cells (MSCs). Our results showed that nutrient gradients prompt the spatiotemporal organization of MSCs in 3D culture. Cells adapted to their 3D environment without significant cell death or cell differentiation. Kinetics data and whole-genome gene expression analysis suggest that a low proliferation activity phenotype predominates in stromal cells cultured in 3D, likely due to increasing nutrient limitation. These differences implied that despite similar surface areas available for cell attachment, higher cell concentrations in 3D reduced MSCs proliferation, while activating hypoxia related-pathways. To further understand the in vivo effects of both proliferation and cell concentrations, we increased cell concentrations in small (1.8 μl) implantable wells. We found that MSCs accumulation and conditioning by nutrient competition in small volumes leads to an ideal threshold of cell-concentration for the induction of blood vessel formation, possibly signaled by the hypoxia-related stanniocalcin-1 gene.

Clinical utility of measuring expression levels of Stanniocalcin 2 in patients with colorectal cancer.

Stanniocalcin 2 (STC2) is a novel member of the Stanniocalcin family, the function of which remains unclear. Its expression is clinically significant in several cancers. The aim of this study was to evaluate the clinical value of measuring expression levels of STC2 in colorectal cancer (CRC) patients. A total of 47 tumor and matched tumor-free margin samples were obtained during surgery. The STC2 mRNA expression level in tumor and marginal tissue was examined by real-time quantitative PCR. STC2 mRNA expression levels were higher in tumor tissues than the control. (r=0.36, p≤0.02). mRNA expression level of STC2 was significantly associated with tumor size (p≤0.05) and histologic grade (p≤0.05). Our study demonstrated that STC2 was significantly expressed in CRC patients, relative to the control. STC2 can therefore be used as a biomarker to differentiate between tumor borders and margins. Analysis of STC2 gene expression during surgery could be useful in reducing surgical error in tumor removal and increasing overall success of surgery with improved tumor clearance. However, in some cases such as where the tumor is end-stage, the expression of such a biomarker may not be clinically beneficial to record. The consideration of marginal samples as a control group can help reduce the effect of confounding factors such as racial and individual differences.

Cyclooxygenase-2 mediates induction of the renal stanniocalcin-1 gene by arginine vasopressin

In rats and mice, the renal stanniocalcin-1 (STC-1) gene is expressed in most nephron segments, but is differentially induced in response to dehydration. In cortical segments STC-1 mRNA levels are upregulated by the hypertonicity of dehydration, while hypovolemia causes gene induction in the inner medulla (papilla). In both cases induction is mediated by arginine vasopressin (AVP) acting via the V2 receptor (V2R). The intent of STC-1 gene upregulation during dehydration has yet to be established. Therefore, to narrow down the range of possible actions, we mapped out the pathway by which V2R occupancy upregulates the gene. V2R occupancy activates two different renal pathways in response to dehydration. The first is antidiuretic in nature and is mediated by direct V2R occupancy. The second pathway is indirect and counter-regulates AVP-mediated antidiuresis. It involves COX-2 (cyclooxygenase-2) and the prostanoids, and is activated by the V2R-mediated rise in medullary interstitial osmolality. The resulting prostanoids counter-regulate AVP-mediated antidiuresis. They also upregulate renal cytoprotective mechanisms. The present studies employed models of COX inhibition and COX gene deletion to address the possible involvement of the COX pathway. The results showed that both general and specific inhibitors of COX-2 blocked STC-1 gene induction in response to dehydration. Gene induction in response to dehydration was also abolished in COX-2 null mice (cortex and papilla), but not in COX-1 null mice. STC-1 gene induction in response to V2R occupancy was also uniquely abolished in COX-2 nulls (both regions). These findings therefore collectively suggest that AVP-mediated elevations in STC-1 gene expression are wholly dependent on functional COX-2 activity. As such, a permissive role for STC-1 in AVP-mediated antidiuresis can be ruled out, and its range of possible actions has been narrowed down to AVP counter-regulation and renal cytoprotection.

Stanniocalcin-1 Co-Localizes with Insulin in the Pancreatic Islets

The polypeptide hormone stanniocalcin-1 (STC-1) is widely expressed in mammals and signals both locally and systemically. In many tissues STC-1 ligand is sequestered by target cell organelles (mitochondria, nuclei, and cholesterol lipid droplets) to exert diverse biological effects. Most notably, STC-1 serves as an uncoupler of oxidative phosphorylation in liver, muscle, and kidney mitochondria. The present paper describes the identification of STC-1 receptors in mouse pancreatic β cells and the discovery that the ligand co-localizes with insulin in pancreatic β cells. In situ hybridization (ISH) analysis subsequently revealed that pancreatic β cells were the source of the ligand. Intriguingly however, all ISH signal was localized over putative islet cell nuclei as opposed to the cell cytoplasm. Real-time qPCR and agarose gel electrophoresis revealed that the STC-1 amplicon generated from islet cell total RNA was the same size as that from kidney. However, relative levels of STC-1 gene expression were >100-fold lower in islets than those in kidney tissue. Collectively, these findings are indicative of a local STC-1 signalling pathway in pancreatic β cells. The role of STC-1 in this context remains to be established, but it could very well entail the regulation of β cell mitochondria membrane potential which is an integral aspect of regulated insulin release. Interestingly, STC-1 immunoreactivity was not evident in embryonic pancreatic islets, suggesting that ligand synthesis may only commence postnatally.