Elevated STC-1 augments the invasiveness of triple-negative breast cancer cells through activation of the JNK/c-Jun signaling pathway

Stanniocalcin 1 in Patients with Refractory Colorectal Cancer Treated with Regorafenib: A Post Hoc Biomarker Analysis of the TEXCAN and CORRECT Trials

SIGNIFICANCE

STC1 is a protein secreted by intratumor endothelial cells in which plasma concentrations increase in patients with chemorefractory mCRC. Based on analyses of patients with refractory mCRC in the TEXCAN and CORRECT trials, we found that STC1 plasma levels had a prognostic role for OS, with high levels associated with poor outcome. A predictive role for baseline STC1 levels was pointed out for regorafenib efficacy.

Unveiling the therapeutic potential and mechanisms of stanniocalcin-1 in retinal degeneration

Retinal degeneration (RD) is a group of ocular diseases characterized by progressive photoreceptor apoptosis and visual impairment. Mitochondrial malfunction, excessive oxidative stress, and chronic activation of neuroglia collectively contribute to the development of RD. Currently, there is a lack of efficacious therapeutic interventions for RD. Stanniocalcin-1 (STC-1) is a promising candidate molecule to decelerate photoreceptor cell death. STC-1 is a secreted calcium/phosphorus regulatory protein that exerts diverse protective effects. Accumulating evidence suggests that STC-1 protects retinal cells from ischemic injury, oxidative stress, and excessive apoptosis through enhancing the expression of uncoupling protein-2 (UCP-2). Furthermore, STC-1 exerts its antiinflammatory effects by inhibiting the activation of microglia and macrophages, as well as the synthesis and secretion of proinflammatory cytokines, such as TNF-α, IL-1, and IL-6. By employing these mechanisms, STC-1 effectively shields the retinal photoreceptors and optic nerve, thereby slowing down the progression of RD. We summarize the STC-1-mediated therapeutic effects on the degenerating retina, with a particular focus on its underlying mechanisms. These findings highlight that STC-1 may act as a versatile molecule to treat degenerative retinopathy. Further research on STC-1 is imperative to establish optimal protocols for its clinical use.

Targeting JNK kinase inhibitors via molecular docking: A promising strategy to address tumorigenesis and drug resistance

Among members of the mitogen-activated protein kinase (MAPK) family, c-Jun N-terminal kinases (JNKs) are vital for cellular responses to stress, inflammation, and apoptosis. Recent advances have highlighted their important implications in cancer biology, where dysregulated JNK signalling plays a role in the growth, progression, and metastasis of tumors. The present understanding of JNK kinase and its function in the etiology of cancer is summarized in this review. By modifying a number of downstream targets, such as transcription factors, apoptotic regulators, and cell cycle proteins, JNKs exert diverse effects on cancer cells. Apoptosis avoidance, cell survival, and proliferation are all promoted by abnormal JNK activation in many types of cancer, which leads to tumor growth and resistance to treatment. JNKs also affect the tumour microenvironment by controlling the generation of inflammatory cytokines, angiogenesis, and immune cell activity. However, challenges remain in deciphering the context-specific roles of JNK isoforms and their intricate crosstalk with other signalling pathways within the complex tumor environment. Further research is warranted to delineate the precise mechanisms underlying JNK-mediated tumorigenesis and to develop tailored therapeutic strategies targeting JNK signalling to improve cancer management. The review emphasizes the role of JNK kinases in cancer biology, as well as their potential as pharmaceutical targets for precision oncology therapy and cancer resistance. Also, this review summarizes all the available promising JNK inhibitors that are suggested to promote the responsiveness of cancer cells to cancer treatment.

Update on JNK inhibitor patents: 2015 to present

INTRODUCTION

c-Jun N-terminal kinase (JNK) regulates various biological processes through the phosphorylation cascade and is closely associated with numerous diseases, including inflammation, cardiovascular diseases, and neurological disorders. Therefore, JNKs have emerged as potential targets for disease treatment.

AREAS COVERED

This review compiles the patents and literatures concerning JNK inhibitors through retrieving relevant information from the SciFinder, Google Patents databases, and PubMed from 2015 to the present. It summarizes the structure-activity relationship (SAR) and biological activity profiles of JNK inhibitors, offering valuable perspectives on their potential therapeutic applications.

EXPERT OPINION

The JNK kinase serves as a novel target for the treatment of neurodegenerative disorders, pulmonary fibrosis, and other illnesses. A variety of small-molecule inhibitors targeting JNKs have demonstrated promising therapeutic potential in preclinical studies, which act upon JNK kinases via distinct mechanisms, encompassing traditional ATP competitive inhibition, covalent inhibition, and bidentate inhibition. Among them, several JNK inhibitors from PregLem SA, Celegene SA, and Xigen SA have accomplished the early stage of clinical trials, and their results will guide the development and indications of future JNK inhibitors.

Stanniocalcin-1 promotes temozolomide resistance of glioblastoma through regulation of MGMT

Temozolomide (TMZ) resistance is a major challenge in the treatment of glioblastoma (GBM). Tumour reproductive cells (TRCs) have been implicated in the development of chemotherapy resistance. By culturing DBTRG cells in three-dimensional soft fibrin gels to enrich GBM TRCs and performing RNA-seq analysis, the expression of stanniocalcin-1 (STC), a gene encoding a secreted glycoprotein, was found to be upregulated in TRCs. Meanwhile, the viability of TMZ-treated TRC cells was significantly higher than that of TMZ-treated 2D cells. Analysis of clinical data from CGGA (Chinese Glioma Genome Atlas) database showed that high expression of STC1 was closely associated with poor prognosis, glioma grade and resistance to TMZ treatment, suggesting that STC1 may be involved in TMZ drug resistance. The expression of STC1 in tissues and cells was examined, as well as the effect of STC1 on GBM cell proliferation and TMZ-induced DNA damage. The results showed that overexpression of STC1 promoted and knockdown of STC1 inhibited TMZ-induced DNA damage. These results were validated in an intracranial tumour model. These data revealed that STC1 exerts regulatory functions on MGMT expression in GBM, and provides a rationale for targeting STC1 to overcome TMZ resistance.

Protein kinase D drives the secretion of invasion mediators in triple-negative breast cancer cell lines

The protein kinase D (PKD) family members regulate the fission of cargo vesicles at the Golgi complex and play a pro-oncogenic role in triple-negative breast cancer (TNBC). Whether PKD facilitates the secretion of tumor-promoting factors in TNBC, however, is still unknown. Using the pharmacological inhibition of PKD activity and siRNA-mediated depletion of PKD2 and PKD3, we identified the PKD-dependent secretome of the TNBC cell lines MDA-MB-231 and MDA-MB-468. Mass spectrometry-based proteomics and antibody-based assays revealed a significant downregulation of extracellular matrix related proteins and pro-invasive factors such as LIF, MMP-1, MMP-13, IL-11, M-CSF and GM-CSF in PKD-perturbed cells. Notably, secretion of these proteins in MDA-MB-231 cells was predominantly controlled by PKD2 and enhanced spheroid invasion. Consistently, PKD-dependent secretion of pro-invasive factors was more pronounced in metastatic TNBC cell lines. Our study thus uncovers a novel role of PKD2 in releasing a pro-invasive secretome.

Emerging phagocytosis checkpoints in cancer immunotherapy

Cancer immunotherapy, mainly including immune checkpoints-targeted therapy and the adoptive transfer of engineered immune cells, has revolutionized the oncology landscape as it utilizes patients' own immune systems in combating the cancer cells. Cancer cells escape immune surveillance by hijacking the corresponding inhibitory pathways via overexpressing checkpoint genes. Phagocytosis checkpoints, such as CD47, CD24, MHC-I, PD-L1, STC-1 and GD2, have emerged as essential checkpoints for cancer immunotherapy by functioning as "don't eat me" signals or interacting with "eat me" signals to suppress immune responses. Phagocytosis checkpoints link innate immunity and adaptive immunity in cancer immunotherapy. Genetic ablation of these phagocytosis checkpoints, as well as blockade of their signaling pathways, robustly augments phagocytosis and reduces tumor size. Among all phagocytosis checkpoints, CD47 is the most thoroughly studied and has emerged as a rising star among targets for cancer treatment. CD47-targeting antibodies and inhibitors have been investigated in various preclinical and clinical trials. However, anemia and thrombocytopenia appear to be formidable challenges since CD47 is ubiquitously expressed on erythrocytes. Here, we review the reported phagocytosis checkpoints by discussing their mechanisms and functions in cancer immunotherapy, highlight clinical progress in targeting these checkpoints and discuss challenges and potential solutions to smooth the way for combination immunotherapeutic strategies that involve both innate and adaptive immune responses.

Nobiletin inhibits breast cancer cell migration and invasion by suppressing the IL-6-induced ERK-STAT and JNK-c-JUN pathways

BACKGROUND

Breast cancer is one of the most common cancers in women, affecting more than 2 million women worldwide annually. However, effective treatments for breast cancer are limited. Nobiletin is a flavonoid present in the dried mature pericarp of mandarin orange (Citrus reticulata Blanco), which is used to prepare Citri Renetulatae Pericarpium and can inhibit tumour growth and progression according to modern pharmacological studies. However, whether nobiletin exhibits an antimetastatic role in breast cancer and its potential mechanism need to be further investigated.

PURPOSE

This study aims to evaluate the inhibitory effect of nobiletin on breast cancer and to elucidate potential mechanisms against invasion and migration.

METHODS

Cell viability was determined by cell counting kit-8 and colony formation assays. Wound healing and Boyden chamber assays detected cancer cell migration and invasion capabilities. Immunoblotting and qPCR were applied to determine the protein and mRNA expression levels of extracellular signal-regulated kinases (ERK) and the c-Jun N-terminal kinase (JNK) signalling pathways. Molecular docking was used to assess the degree of nobiletin binding to phosphatidylinositol 3-kinase (PI3K). Xenografts and liver metastases were constructed in BALB/c nude mice to evaluate the anticancer effect of nobiletin in vivo. H&E staining and immunohistochemistry were used to detect proliferation and the expression of related proteins.

RESULTS

Nobiletin induced cell death in a concentration- and time-dependent manner and possessed anti-invasion and anti-migration effects on MCF-7 and T47D cells by suppressing the interleukin-6-induced ERK and JNK signalling pathways. In addition, nobiletin docked with the binding site of PI3K, and the binding score was -8.0 kcal/mol. Furthermore, the inhibition of breast cancer growth and metastasis by nobiletin was demonstrated by constructing xenografts and liver metastases in vivo.

CONCLUSION

Nobiletin inhibited liver metastasis of breast cancer by downregulating the ERK-STAT and JNK-c-JUN pathways, and its safety and efficacy were verified, indicating the potential of nobiletin as an anticancer agent.

Icariin Induces Triple-Negative Breast Cancer Cell Apoptosis and Suppresses Invasion by Inhibiting the JNK/c-Jun Signaling Pathway

Background

Breast cancer is a common cancer worldwide. Triple-negative breast cancer (TNBC) is an aggressive form of breast cancer characterized by a poor prognosis. Icariin (ICA) is a flavonoid glycoside purified from the natural product Epimedium, which is reported to exert an inhibitory effect on a variety of cancers. However, molecular mechanisms behind ICA suppressed TNBC remain elusive.

Methods

The curative effects of ICA on TNBC cells and potential targets were predicted by network pharmacology and molecular biology methods screening, and the mechanism of inhibition was explained through in vitro experiments such as cell function determination, Western blot analysis, molecular docking verification, etc.

Results

This study showed that ICA inhibits TNBC cell functions such as proliferation, migration, and invasion in a dose-dependent manner. ICA could induce redox-induced apoptosis in TNBC cell, as shown by ROS upregulation. As a result of network pharmacology, ICA was predicted to be able to inhibit the MAPK signaling pathway. ICA treatment inhibited the expression of JNK and c-Jun and downregulated the antiapoptotic gene cIAP-2. Our results suggested that ICA could induce apoptosis by inducing an excessive accumulation of ROS in cells and suppress TNBC cell invasion via the JNK/c-Jun signaling pathway.

Conclusion

We demonstrated that ICA can effectively inhibit cell proliferation and induced apoptosis of TNBC cells. In addition, ICA could inhibit TNBC cell invasion through the JNK/c-Jun signaling pathway. The above suggests that ICA may become a potential drug for TNBC.

Development and validation of novel risk prediction models of breast cancer based on stanniocalcin‐1 level

PURPOSE

The function of stanniocalcin-1 (STC-1) in the oncogenesis and progression of tumors has been extensively studied. The purpose of this study was to investigate the relationship between secreted STC-1 and prognosis in patients with breast cancer (BC) and to determine whether STC-1 could be a key prognostic factor in BC.

METHODS

The STC-1 level was measured by ELISA and clinical data from 1210 female patients with BC were used to develop and validate nomograms. We then verified the models through the plotting of ROC curves and calibration curves, calculating the C-index, and performing decision curve analyses (DCA).

RESULTS

The level of STC-1 in the peripheral plasma was significantly correlated with the T stage, N stage, clinical stage, grade, hormone receptors, HER-2 status, and tumor subtype. Cox regression analyses revealed that estrogen receptor(ER) status, N stage, and STC-1 level were risk factors for overall survival (OS), whereas T stage, N stage, and STC-1 level were independent prognostic factors for distant disease-free survival (DDFS) and disease-free survival (DFS). Both the ROC curve and the C-index confirmed the high resolution of these models, while the DCA identified the feasibility of their practical application. In addition, the calibration curves indicated good consistency between the predicted and actual survival rates.

CONCLUSION

Nomograms were created based on STC-1 levels for 3-, 5-, and 7-year OS, DDFS, and DFS of patients with BC respectively. As a key prognostic factor for BC, peripheral blood STC-1 level can be used clinically as a liquid biopsy indicator.

Circular RNA circPOSTN promotes neovascularization by regulating miR-219a-2-3p/STC1 axis and stimulating the secretion of VEGFA in glioblastoma

Glioblastoma (GBM), the most malignant type of astrocytic tumor, is one of the deadliest cancers prevalent in adults. Along with tumor growth, patients with GBM generally suffer from extensive cerebral edema and apparent symptoms of intracranial hyper-pressure. Accumulating evidence has demonstrated that circRNA plays a critically important role in tumorigenesis and progression. However, the biological function and the underlying mechanism of circRNA in GBM remain elusive. In this study, by conducting gene expression detection based on 15 pairs of GBM clinical specimens and the normal adjunct tissues, we observed that circPOSTN showed abnormally higher expression in GBM. Both loss-of-function and gain-of-function biological experiments demonstrated that circPOSTN scheduled the proliferation, migration, and neovascularization abilities of GBM cells. Further, fluorescence in situ hybridization (FISH) assay, quantitative RT-PCR, and subcellular separation suggested that circPOSTN was predominately localized in the cytoplasm and may serve as a competing endogenous RNA (ceRNA). CircRNA-miRNA interaction prediction based on online analytical processing, AGO2-RIP assay, biotin labeled RNA pulldown assay, and dual-luciferase reporter assay revealed that circPOSTN sponged miR-219a-2-3p, limited its biological function, and ultimately upregulated their common downstream gene STC1. Finally, by carrying out in vitro and in vivo functional assays, we uncovered a new regulatory axis circPOSTN/miR-219a-2-3p/STC1 that promoted GBM neovascularization by increasing vascular endothelial growth factor A (VEGFA) secretion. Our study underscores the critical role of circPOSTN in GBM progression, providing a novel insight into GBM anti-tumor therapy.

Comprehensive Analyses of Stromal-Immune Score-Related Competing Endogenous RNA Networks In Colon Adenocarcinoma

Although recent clinical investigations emphasize the roles of myriad diversities of RNAs in stromal and immune components in the tumor microenvironment, especially in colon adenocarcinoma, however, analyses of “competing endogenous RNAs (ceRNA)” network in association with stromal and immune scores have yet to be determined. This study was conducted to explore the regulatory mechanisms of a stromal-immune score-based ceRNA network in colon adenocarcinoma. Stromal and immune scores of colon adenocarcinoma tumor samples were calculated by using the ESTIMATE algorithm. Differential expression analysis between samples with high/low stromal and immune scores was performed, followed by functional annotation for the overlapping DEmRNAs. The ceRNA network was constructed by differential expression analysis, prediction of RNA-RNA interaction, and correlation with clinicopathological parameters of the patients, which were further verified by external datasets and experiments. Colon adenocarcinoma patients having higher immune scores exhibited prolonged overall survival. RNA dataset analyses from TCGA revealed aberrant expressions of a total of 2052 mRNAs, 108 lncRNAs, and 70 miRNAs between high and low stromal/immune groups. Functional annotation mapped the differentially overexpressed mRNAs for immune-associated GO terms. To construct the ceRNA network, a total of 48 lncRNAs, 40 miRNAs, and 199 mRNAs were sorted out. A dysregulated ceRNA network consisting of 6 lncRNAs, 11 miRNAs, and 39 mRNAs was constructed by comparing RNA expressions between cancer as well as adjacent normal tissues. The ceRNA regulatory axis “MIAT/miR-532-3p/STC1” was regarded as a potential hit by the comprehensive analysis. The RT-qPCR assay showed upregulation of MIAT and STC1 while downregulation of hsa-miR-532-3p expression in cancer. Thus, our study highlights the potential role of a stromal-immune score-based ceRNA network in the colon adenocarcinoma microenvironment. The ceRNA axis MIAT/miR-532-3p/STC1 could serve as a promising therapeutic target for colon adenocarcinoma.

Serum Autoantibodies against LRDD, STC1, and FOXA1 as Biomarkers in the Detection of Ovarian Cancer

Purpose

This study is aimed at evaluating serum autoantibodies against four tumor-associated antigens, including LRDD, STC1, FOXA1, and EDNRB, as biomarkers in the immunodiagnosis of ovarian cancer (OC).

Methods

The autoantibodies against LRDD, STC1, FOXA1, and EDNRB were measured using an enzyme-linked immunosorbent assay (ELISA) in 94 OC patients and 94 normal healthy controls (NHC) in the research group. In addition, the diagnostic values of different autoantibodies were validated in another independent validation group, which comprised 136 OC patients, 136 NHC, and 181 patients with benign ovarian diseases (BOD).

Results

In the research group, autoantibodies against LRDD, STC1, and FOXA1 had higher serum titer in OC patients than NHC (P < 0.001). The area under receiver operating characteristic curves (AUCs) of these three autoantibodies were 0.910, 0.879, and 0.817, respectively. In the validation group, they showed AUCs of 0.759, 0.762, and 0.817 and sensitivities of 49.3%, 42.7%, and 48.5%, respectively, at specificity over 90% for discriminating OC patients from NHC. For discriminating OC patients from BOD, they showed AUCs of 0.718, 0.729, and 0.814 and sensitivities of 47.1%, 39.0%, and 51.5%, respectively, at specificity over 90%. The parallel analyses demonstrated that the combination of anti-LRDD and anti-FOXA1 autoantibodies achieved the optimal diagnostic performance with the sensitivity of 58.1% at 87.5% specificity and accuracy of 72.8%. The positive rate of the optimal autoantibody panel improved from 62.4% to 87.1% when combined with CA125 in detecting OC patients.

Conclusion

Serum autoantibodies against LRDD, STC1, and FOXA1 have potential diagnostic values in detecting OC.

Molecular and Clinical Significance of Stanniocalcin-1 Expression in Breast Cancer Through Promotion of Homologous Recombination-Mediated DNA Damage Repair

Stanniocalcin-1 (STC1) is a glycoprotein hormone whose abnormal expression has been reported to be associated with a variety of tumors, but its function in breast cancer is not well understood. Through modulation of STC1 expression in different breast cancer cell lines, our study found that STC1 could promote the proliferation and growth of breast cancer cells and promote metastasis. Furthermore, STC1 reduced apoptosis induction by irradiation. We also found that STC1 could promote a homologous recombination-mediated DNA damage repair by recruiting BRCA1 to sites of damage. Moreover, STC1 silencing sensitized breast cancer cells to treatment with irradiation (IR), olaparib, or cisplatin in vitro. In clinical settings, the serum concentration of STC1 was higher in breast cancer patients than in healthy women, as detected by enzyme-linked immunosorbent assay (ELISA). In addition, immunohistochemical staining of breast cancer specimens showed that a high expression of STC1 was negatively correlated with recurrence-free survival in breast cancer, indicating that STC1 expression could be used as a predictive marker for a poor prognosis in breast cancer. All these findings indicate that STC1 promotes breast cancer tumorigenesis and that breast cancers with a high level of STC1 are more resistant to treatment, probably through homologous recombination (HR) promotion. Furthermore, combining STC1 inhibition and DNA damage-inducing drugs may be a novel approach to improve the survival of patients with STC1-expressing breast cancer.

Effects and prognostic values of miR-30c-5p target genes in gastric cancer via a comprehensive analysis using bioinformatics

Gastric cancer (GC) is a common cancer and the leading cause of cancer-related death worldwide. To improve the diagnosis and treatment of GC, it is necessary to identify new biomarkers by investigating the cellular and molecular mechanisms. In this study, miR-30c-5p expression was significantly down-regulated in GC tissues by comprehensive analysis using multiple databases. The target genes of miR-30c-5p with up-regulated expression level in GC were identified, including ADAM12 (a disintegrin and metalloproteinase12), EDNRA (the Endothelin receptor type A), STC1 (stanniocalcin 1), and CPNE8 (the calcium-dependent protein, copine 8). The expression level of ADAM12 was significantly related to depth of invasion (p = 0.036) in GC patients. The expression level of EDNRA was significantly related to grade (P = 0.003), depth of invasion (P = 0.019), and lymphatic metastasis (P = 0.001). The expression level of CPNE8 was significantly related to grade (P = 0.043) and TNM stage (P = 0.027).Gene set enrichment analysis showed that they might participate in GC progression through cancer-related pathways. CIBERSORT algorithm analysis showed that their expressions were related to a variety of tumor-infiltrating immune cells. The higher expression of those target genes might be the independent risk factor for poor survival of GC patients, and they might be potential prognostic markers in GC patients.

Low Expression of Stanniocalcin 1 (STC-1) Protein Is Associated With Poor Clinicopathologic Features of Endometrial Cancer

Stanniocalcin-1 (STC-1) is a glycoprotein hormone involved in diverse biological processes, including regulation of calcium phosphate homeostasis, cell proliferation, apoptosis, inflammation, oxidative stress responses, and cancer development. The role of STC-1 in endometrial cancer (EC) is yet to be elucidated. In this study, we investigated the protein expression pattern of STC-1 in a tissue microarray (TMA) cohort of hysterectomy specimens from 832 patients with EC. We then evaluated the prognostic value of STC-1 expression regarding the clinicopathologic features and patients survival over a period of 140 months. Our results revealed that in EC tissue samples, STC-1 is mainly localized in the endometrial epithelium, although some expression was also observed in the stroma. Decreased STC-1 expression was associated with factors relating to a worse prognosis, such as grade 3 endometrioid tumors (p = 0.030), deep myometrial invasion (p = 0.003), lymphovascular space invasion (p = 0.050), and large tumor size (p = 0.001). Moreover, STC-1 expression was decreased in tumors obtained from obese women (p = 0.014) and in women with diabetes mellitus type 2 (DMT2; p = 0.001). Interestingly, the data also showed an association between DNA mismatch repair (MMR) deficiency and weak STC-1 expression, specifically in the endometrial epithelium (p = 0.048). No association was observed between STC-1 expression and disease-specific survival. As STC-1 expression was particularly low in cases with obesity and DMT2 in the TMA cohort, we also evaluated the correlation between metformin use and STC-1 expression in an additional EC cohort that only included women with DMT2 (n = 111). The analysis showed no difference in STC-1 expression in either the epithelium or the stroma in women undergoing metformin therapy compared to metformin non-users. Overall, our data may suggest a favorable role for STC-1 in EC behavior; however, further studies are required to elucidate the detailed mechanism and possible applications to cancer treatment.

STC1 is a Novel Biomarker Associated with Immune Characteristics and Prognosis of Bladder Cancer

Background

Stanniocalcin-1 (STC1) is a well-studied oncogene that promotes different types of cancer progression. However, the expression status of STC1, the values of STC1 on prognosis, and its immune characteristic in bladder cancer (BLCA) have not been well examined.

Methods

The expression of STC1 and its clinicopathological as well as immune characteristics in BLCA samples were firstly identified in The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases. Immunohistochemistry (IHC) performed on the tissue microarray (TMA) slide was further used to validate the expression of STC1 and its relationship with immune features in 16 non-muscle invasive bladder cancer (NMIBC) samples and 42 muscle invasive bladder cancer (MIBC) samples.

Results

The expression of STC1 was upregulated in higher stage BLCA. High STC1 expression also predicted poor prognosis in BLCA. Subsequently, the TMA validated the expression and prognostic value of STC1 in BLCA. Bioinformatics analysis demonstrated that STC1 and common immune checkpoints as well as immune markers of various immune cells were positively correlated in TCGA. In addition, IHC data from the TMA further validated that tumor cells with higher STC1 level tended to express higher PDL1 as well as increased infiltration of CD3+ T cells.

Conclusion

To our knowledge, this is the first comprehensive study that investigates the clinical and immune characteristics of STC1 in BLCA. It may provide new insight into the function of STC1 in regulating tumor immune microenvironment. Further studies are warranted to uncover the potential mechanisms that mediate STC1 expression and tumor immunity in BLCA.

Potentiating Therapeutic Effects of Epidermal Growth Factor Receptor Inhibition in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is a subset of breast cancer with aggressive characteristics and few therapeutic options. The lack of an appropriate therapeutic target is a challenging issue in treating TNBC. Although a high level expression of epidermal growth factor receptor (EGFR) has been associated with a poor prognosis among patients with TNBC, targeted anti-EGFR therapies have demonstrated limited efficacy for TNBC treatment in both clinical and preclinical settings. However, with the advantage of a number of clinically approved EGFR inhibitors (EGFRis), combination strategies have been explored as a promising approach to overcome the intrinsic resistance of TNBC to EGFRis. In this review, we analyzed the literature on the combination of EGFRis with other molecularly targeted therapeutics or conventional chemotherapeutics to understand the current knowledge and to provide potential therapeutic options for TNBC treatment.

YAP-TEAD up-regulates IRS2 expression to induce and deteriorate oesophageal cancer

Oesophageal cancer (EC) represents a significant cause of cancer worldwide. Yes‐associated protein (YAP) is reported to correlate with the initiation of multiple cancers including EC, but the underlying mechanism remains elusive. The current study aimed to investigate the molecular mechanism of YAP‐TEAD in the occurrence and progression of EC. EC tissues and cells were obtained, followed by determination of the expression of YAP, c‐Jun, pc‐Jun and IRS2. The effect of YAP‐TEAD on the biological EC cell processes was explored through gain‐ and loss‐of‐function approaches. The interaction between YAP and TEAD was detected by co‐immunoprecipitation. The binding of TEAD to the c‐Jun promoter was determined using chromatin immunoprecipitation. Tumour formation in the nude mice was detected in order to ascertain the effect of YAP and IRS2 in vivo. We found elevated YAP in the EC tissues and cells. YAP silencing led to a decrease in EC cell proliferation, invasion and sphere formation. YAP‐TEAD complex bound to the promotor of c‐Jun, and c‐Jun led to an increase in the expression of IRS2 through the JNK/c‐Jun pathway. Additionally, pc‐Jun and phosphorylated JNK were localized in the nuclear in addition to displaying enhanced expression in the EC tissues. IRS2 overexpression negated the inhibition of cell proliferation, invasion and sphere formation triggering YAP silencing. YAP up‐regulated IRS2 and aggravated EC in vivo. Taken together, YAP‐TEAD activates the JNK/c‐Jun pathway to up‐regulate IRS2, ultimately promoting EC progression. Therefore, YAP‐TEAD inhibition could be a promising therapeutic approach for EC treatment.

＜Editors' Choice＞ Stanniocalcin-1 mRNA expression in soft-tissue tumors

Stanniocalcin-1 (STC1) is a glycoprotein that was originally identified as a calcium-regulating hormone in bony fish, and that has been shown to also critically mediate cell growth, proliferation and differentiation, etc. in humans. Increased STC1 expression levels have been previously detected in different human cancer samples, such as those isolated from lung, breast, ovary, colon, pancreas, and liver tumors; thus, the present study evaluated STC1 expression in various soft-tissue tumors. STC1 mRNA isolated from 16 cell lines and 186 clinical soft-tissue tumor specimens were analyzed via quantitative real-time PCR, and the calculated expression levels were normalized to those exhibited by STC1-expressing MDA-MB-231 cells. The results of these analyses did not reveal any specific histological tumor types that displayed significantly increased STC1 expression; however, they did not indicate that STC1 expression was significantly higher in malignant compared to benign soft-tissue tumors. Furthermore, in adipocytic tumors, STC1 expression in dedifferentiated liposarcomas was found to be highest and lowest in lipoma tissues, respectively, suggesting that adipocytic tumors may express increasely high levels of STC1 mRNA as they become histologically more advanced. STC1 expression correlates with the malignancy grade in soft-tissue tumors.

Characterizing Endocrine Status, Tumor Hypoxia and Immunogenicity for Therapy Success in Epithelial Ovarian Cancer

Epithelial ovarian cancer is predominantly diagnosed at advanced stages which creates significant therapeutic challenges. As a result, the 5-year survival rate is low. Within ovarian cancer, significant tumor heterogeneity exists, and the tumor microenvironment is diverse. Tumor heterogeneity leads to diversity in therapy response within the tumor, which can lead to resistance or recurrence. Advancements in therapy development and tumor profiling have initiated a shift from a "one-size-fits-all" approach towards precision patient-based therapies. Here, we review aspects of ovarian tumor heterogeneity that facilitate tumorigenesis and contribute to treatment failure. These tumor characteristics should be considered when designing novel therapies or characterizing mechanisms of treatment resistance. Individual patients vary considerably in terms of age, fertility and contraceptive use which innately affects the endocrine milieu in the ovary. Similarly, individual tumors differ significantly in their immune profile, which can impact the efficacy of immunotherapies. Tumor size, presence of malignant ascites and vascular density further alters the tumor microenvironment, creating areas of significant hypoxia that is notorious for increasing tumorigenesis, resistance to standard of care therapies and promoting stemness and metastases. We further expand on strategies aimed at improving oxygenation status in tumors to dampen downstream effects of hypoxia and set the stage for better response to therapy.

Trichostatin A Induces Autophagy in Cervical Cancer Cells by Regulating the PRMT5-STC1-TRPV6-JNK Pathway

OBJECTIVE

The aim of this study was to investigate the effects of trichostatin A (TSA) on cervical cancer and the related mechanisms.

METHODS

The HeLa and Caski cervical cancer cell lines were treated with different concentrations of TSA. Cell viability was measured by MTT assays. Cell apoptosis was analysed using flow cytometry. Expression of transient receptor potential cation channel, subfamily V, member 6 (TRPV6), protein arginine methyltransferase 5 (PRMT5), and stanniocalcin 1 (STC1) was determined by qRT-PCR and Western blotting. Protein levels of LC3 II/I, beclin1, p62, JNK, and p-JNK were detected by Western blotting.

RESULTS

Treatment with TSA significantly decreased HeLa and Caski cell viability and enhanced the apoptosis rate in a dose-dependent manner. TSA markedly elevated beclin1 protein levels and the LC3 II/I ratio and significantly reduced p62 levels in a dose-dependent manner. In addition, TSA (1 μM) significantly suppressed PRMT5 and TRPV6 levels and enhanced STC1 and p-JNK levels. The lysosomal inhibitor bafilomycin-A1 synergistically enhanced the TSA-mediated increase in autophagic flux. Either the overexpression of TRPV6 or the inhibition of JNK signalling markedly enhanced cell viability, inhibited apoptosis, and autophagy and reduced p-JNK levels in TSA-treated cells. The inhibition of STC1 significantly increased TRPV6 protein levels and reduced p-JNK levels. Overexpression of PRMT5 dramatically decreased STC1 and p-JNK protein levels and increased TRPV6 levels.

CONCLUSION

TSA suppresses cervical cancer cell proliferation and induces apoptosis and autophagy through regulation of the PRMT5/STC1/TRPV6/JNK axis.

MicroRNA-34c Inhibits Osteogenic Differentiation and Valvular Interstitial Cell Calcification via STC1-Mediated JNK Pathway in Calcific Aortic Valve Disease

Calcific aortic valve disease (CAVD), a common heart valve disease, is increasingly prevalent worldwide and causes high morbidity and mortality. Here, we aimed to investigate a possible role for miR-34c in the development of osteogenic differentiation during CAVD and to find out the underlying mechanisms. Valvular interstitial cells (VICs) were isolated from the clinical aortic valve tissue samples of CAVD patients and patients with acute aortic dissection and collected. Then, RT-qPCR was performed to determine miR-34c expression and western blot analysis was applied to confirm the relevant protein expression in these VICs. Dual luciferase reporter gene assay was applied to confirm the relation between miR-34c and STC1. Alkaline phosphatase (ALP) staining and alizarin red staining was performed to further confirm the degree of calcification in these samples. MiR-34c was lowly expressed and STC1 was highly expressed in the CAVD tissues. Furthermore, STC1 was the target of miR-34c and was negatively regulated by miR-34c. Overexpression of miR-34c in VICs was concomitant with suppression of both STC1 expression and phosphorylation level of c-Jun N-terminal kinase (JNK). In addition, significant decrease of bone morphogenetic protein-2 (BMP2) and osteocalcin, as well as the decrease of calcification degree were also observed in VICs with miR-34c overexpressed. Taken together, miR-34c could inhibit osteogenic differentiation and calcification of VICs by suppressing the STC1/JNK signaling pathway in CAVD, making miR-34c a novel therapeutic target for the treatment of CAVD.

Expression, function and clinical application of stanniocalcin-1 in cancer

The glycoprotein stanniocalcin-1 functions as a regulatory endocrine hormone that maintains the balance of calcium and phosphorus in bony fish and as a paracrine/autocrine factor involved in many physiological/pathological processes in humans, including carcinogenesis. In this review, we provide an overview of (a) the possible mechanisms through which STC1 affects the malignant properties of cancer, (b) transcriptional and post-transcriptional regulation pathways of STC1 and (c) the potential clinical relevance of STC1 as a cancer biomarker and even a therapeutic target in the future. Exploring the role of STC1 in cancer development may provide a better understanding of the tumorigenesis process in humans and may facilitate finding an effective therapeutic method against cancer.

Robust pathway sampling in phenotype prediction. Application to triple negative breast cancer

Background

Phenotype prediction problems are usually considered ill-posed, as the amount of samples is very limited with respect to the scrutinized genetic probes. This fact complicates the sampling of the defective genetic pathways due to the high number of possible discriminatory genetic networks involved. In this research, we outline three novel sampling algorithms utilized to identify, classify and characterize the defective pathways in phenotype prediction problems, such as the Fisher’s ratio sampler, the Holdout sampler and the Random sampler, and apply each one to the analysis of genetic pathways involved in tumor behavior and outcomes of triple negative breast cancers (TNBC). Altered biological pathways are identified using the most frequently sampled genes and are compared to those obtained via Bayesian Networks (BNs).

Results

Random, Fisher’s ratio and Holdout samplers were more accurate and robust than BNs, while providing comparable insights about disease genomics.

Conclusions

The three samplers tested are good alternatives to Bayesian Networks since they are less computationally demanding algorithms. Importantly, this analysis confirms the concept of “biological invariance” since the altered pathways should be independent of the sampling methodology and the classifier used for their inference. Nevertheless, still some modifications are needed in the Bayesian networks to be able to sample correctly the uncertainty space in phenotype prediction problems, since the probabilistic parameterization of the uncertainty space is not unique and the use of the optimum network might falsify the pathways analysis.

The stress-activated protein kinase pathway and the expression of stanniocalcin-1 are regulated by miR-146b-5p in papillary thyroid carcinogenesis

Papillary thyroid cancer (PTC) is the most common type of thyroid cancer. Deciphering the pathophysiological mechanisms that contribute to PTC development is essential to the discovery of optimal diagnostic and therapeutic approaches. MiR-146b-5p has been identified as a cancer-associated microRNA highly up-regulated in PTC. This study explores the hypothesis that miR-146b-5p contributes to papillary thyroid carcinogenesis through regulation of cell signaling pathways in a manner that overcomes the cellular growth suppressive events and provides survival advantage. The effect of miR-146b-5p inhibition on major cancer related signaling pathways and expression of Stanniocalcin-1 (STC1), an emerging molecule associated with stress response and carcinogenesis, was tested in cultured primary thyroid cells using luciferase reporter assays, quantitative real-time PCR, immunofluorescence staining, and flow cytometry. Our results demonstrated that miR-146b-5p inhibits the JNK/AP1 pathway activity and down-regulates the expression of STC-1 in thyroid-cultured cells and in thyroid tissue samples. In the presence of miR-146b-5p, PTC cells were resistant to cell death in response to oxidative stress. This is a novel report that miR-146b-5p directly targets STC1 and regulates the activity of JNK/AP1 pathway. Considering the importance of the JNK/AP1 pathway and STC1 in mediating many physiological and pathological processes like apoptosis, stress response and cellular metabolism, a biological regulator of these pathways would have a great scientific and clinical significance.

Selective inhibitors for JNK signalling: a potential targeted therapy in cancer

c-Jun N-terminal kinase (JNK) signalling regulates both cancer cell apoptosis and survival. Emerging evidence show that JNK promoted tumour progression is involved in various cancers, that include human pancreatic-, lung-, and breast cancer. The pro-survival JNK oncoprotein functions in a cell context- and cell type-specific manner to affect signal pathways that modulate tumour initiation, proliferation, and migration. JNK is therefore considered a potential oncogenic target for cancer therapy. Currently, designing effective and specific JNK inhibitors is an active area in the cancer treatment. Some ATP-competitive inhibitors of JNK, such as SP600125 and AS601245, are widely used in vitro; however, this type of inhibitor lacks specificity as they indiscriminately inhibit phosphorylation of all JNK substrates. Moreover, JNK has at least three isoforms with different functions in cancer development and identifying specific selective inhibitors is crucial for the development of targeted therapy in cancer. Some selective inhibitors of JNK are identified; however, their clinical studies in cancer are relatively less conducted. In this review, we first summarised the function of JNK signalling in cancer progression; there is a focus on the discussion of the novel selective JNK inhibitors as potential targeting therapy in cancer. Finally, we have offered a future perspective of the selective JNK inhibitors in the context of cancer therapies. We hope this review will help to further understand the role of JNK in cancer progression and provide insight into the design of novel selective JNK inhibitors in cancer treatment.

Role of stanniocalcin-1 in breast cancer

Breast cancer is a highly heterogeneous disease consisting of five disease subtypes with distinct histological characteristics, clinical behaviors and prognostic features. Stanniocalcin-1 (STC1) is a secreted glycoprotein hormone that has been demonstrated to regulate calcium and phosphate homeostasis. Mammalian STC1 is expressed in various tissues and is implicated in multiple physiological and pathophysiological processes. In addition, growing evidence has suggested that STC1 serves an oncogenic role in a number of different types of tumor. However, the role of STC1 in breast cancer is complex, considering that some studies have shown that it exerts an oncogenic role, whereas other studies have demonstrated the opposite. The aim of the present review article is to evaluate the currently available data on mammalian STC1 and discuss its potential roles in each subtype of breast cancer.

STC1 regulates glioblastoma migration and invasion via the TGF‑β/SMAD4 signaling pathway

Stanniocalcin-1 (STC1) is involved in cancer progression; however, the function of STC1 in glioblastoma remains unknown. In the present study, the expression levels of STC1 protein in glioblastoma were detected using immunohistochemistry. The expression levels of STC1, SMAD2/3 and SMAD4 proteins, following silencing of STC1, were assessed via western blotting. EdU and Transwell assays were performed to determine the proliferation and migration ability of the cells. The mRNA expression levels of STC1, SMAD4 and microRNA (miR)-34a were determined using quantitative PCR. The expression levels of STC1 were increased in glioblastoma tissues. STC1 revealed a significant association with poor outcome in patients with glioblastoma (P<0.05). The proliferation and invasion abilities were repressed in LN229 cells infected with LV3-shSTC1-1 and LV3-shSTC1-2 compared with LV3-NC. By contrast, the proliferation and invasion abilities were increased in T98G cells infected with LV5-STC1 compared with LV5-NC (P<0.05). The expression levels of STC1, SMAD2/3 and SMAD4 were decreased in LN229 cells infected with LV3-shSTC1-1 and LV3-shSTC1-2 compared with LV3-NC. However, the expression levels of STC1, SMAD2/3 and SMAD4 were elevated in T98G cells infected with LV5-STC1 compared with LV5-NC. The expression levels of miR-34a were decreased following silencing of STC1 (P<0.05). The expression levels of SMAD4 were decreased when transfected with miR-34a mimics (P<0.05). The luciferase activity of the wild-type 3′untranslated region of SMAD4 was decreased following transfection with miR-34a mimics (P<0.05). Silencing of STC1 inhibited the growth of LN229 in vivo. In conclusion, STC1 expression levels were increased in the present study, and it was revealed that STC1 regulated glioblastoma malignancy. This phenotype was observed in the SMAD2/3 and SMAD4 pathways.

Chelerythrine Inhibits Human Hepatocellular Carcinoma Metastasis in Vitro

Chelerythrine (CHE) is a type of benzophenanthridine alkaloid found in many herbs and is also the main alkaloid constituent of Toddalia asiatica (L.) LAM. It has been proven to have various activities including antitumor, antifungal, anti-inflammatory and anti-parasitic effects. We have previously demonstrated that CHE can inhibit proliferation and promote apoptosis in human hepatocellular carcinoma (HCC) cells. However, the effect of CHE on the metastasis of HCC and its related molecular mechanisms have yet to be validated. In this study, we investigated the effects of CHE on the migration and invasion of the HCC cell line Hep3B. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), wounding healing, transwell migration and invasion assays and cytoskeleton staining demonstrated that CHE could inhibit the migration and invasion of Hep3B cells in a dose-dependent manner with change of cell structure. RNA interference studies made a knockdown of matrix metalloproteinase (MMP)-2/9 respectively in Hep3B cells. And the results of wounding healing and transwell invasion assay with the treatment of small interfering RNA (siRNA) investigated that MMP-2/9 are positively associated with Hep3B cell metastasis. The results of enzyme-linked immunosorbent assay (ELISA), Western blotting and quantitative RT-PCR showed that CHE suppressed the expression of MMP-2/9 at both mRNA and protein levels. CHE also exhibited an inhibitory effect on the phosphorylation of Focal adhesion kinase (FAK), phosphatidylinositol 3-kinase (PI3K), Akt, mammalian target of rapamycin (mTOR), c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinases (ERK) and p38. In summary, on Hep3B cells, CHE could change the cell cytoskeletal structures through reducing the expression of p-FAK and inhibit the metastasis of Hep3B cells by downregulating the expression of MMP-2/9 mainly through PI3K/Akt/mTOR signaling pathway.

Secretory Stanniocalcin 1 promotes metastasis of hepatocellular carcinoma through activation of JNK signaling pathway

The hypoxic microenvironment is well-characterized in hepatocellular carcinoma (HCC). Delineation of hypoxia-responsive events is an integral part to understand the pathogenesis of HCC. We studied the functional role and clinical relevance of Stanniocalcin 1 (STC1), a hypoxia-induced molecular target, in HCC. In our clinical cohort, STC1 transcript was up-regulated in HCC tumor tissues. Moreover, STC1 protein was detected in the sera of HCC patients. A higher serum STC1 level was correlated with larger tumor size and poorer 5-year disease-free survival. Functionally, recombinant STC1 protein (rhSTC1) promoted cell migration and cell invasion in vitro; and the effect was abolished by co-treatment of anti-STC1 neutralizing antibody. By in vivo mouse model, silencing of STC1 in HCC cells downregulated secretory STC1 level and suppressed lung metastasis. Furthermore, we found that rhSTC1 activated the JNK pathway, as evidenced by altered expression of the key molecular targets pJNK and p-c-Jun. The functional effects conferred by rhSTC1 were abrogated by co-treatment of JNK inhibitor. In summary, secretory STC1 enhances metastatic potential of HCC via JNK signaling. It potentially serves as a prognostic serum biomarker and a therapeutic target for HCC.

Depletion of carbonic anhydrase IX abrogates hypoxia-induced overexpression of stanniocalcin-1 in triple negative breast cancer cells

Carbonic anhydrase IX (CAIX) is a pH-regulating enzyme that plays a key role in maintaining an alkaline intracellular pH under hypoxic conditions. It is overexpressed in a variety of solid cancers, including breast cancer (BC), and has been implicated in the migration, invasion and stemness of breast cancer cells. Therefore, CAIX recently emerged as a novel therapeutic target for the treatment of BC. To gain an insight into the mechanism of action of CAIX inhibitors, we investigated the impact of CAIX knock-down on the transcriptional response to hypoxia in 2 BC cell lines - MCF7 and MDA-MB-231, by performing a global gene expression analysis. This showed that CAIX knock-down had a relatively minor effect on the global transcriptional response to hypoxia, however it blocked hypoxia-induced upregulation of stanniocalcin-1 (STC1), a secreted glycoprotein that has been shown to promote tumor progression and metastasis in BC. Kaplan-Meier survival analysis showed that high STC1 expression is significantly associated with poor survival in patients with basal-type breast cancer but not luminal A and HER2+ subtypes. Moreover, the association was particularly high in a subgroup of basal-type BC patients with TP53 mutations thus revealing a putative cooperation of STC1 with mutated TP53 in generating highly aggressive BC subgroup. Taken together, these findings show that CAIX inhibitors at least partially act through blocking STC1 induction in BC cells and reveal a subgroup of BC patients, who potentially would benefit most from the treatment with CAIX inhibitors.