Stonin 2 Overexpression is Correlated with Unfavorable Prognosis and Tumor Invasion in Epithelial Ovarian Cancer

Molecular typing and prognostic risk models for ovarian cancer: a study based on cell differentiation trajectory

Ovarian cancer is a heterogeneous disease with different molecular phenotypes. We performed molecular typing of ovarian cancer using cell differentiation trajectory analysis and proposed a prognostic risk scoring model. Using the copy number variation provided by inferCNV, we identified malignant tumor cells. Then, ovarian cancer samples were divided into four subtypes based on differentiation-related genes (DRGs). There were significant differences in survival rates, clinical features, tumor microenvironment scores, and the expression levels of ICGs among the subtypes. Based on nine DRGs, a prognostic risk score model was generated (AUC at 1 year: 0.749; 3 years: 0.651). Then we obtained a nomogram of the prognostic variable combination, including risk scores and clinicopathological characteristics, and predicted the 1-, 3- and 5-year overall survival. Finally, we explored some issues of immune escape using the established risk model. Our study demonstrates the significant influence of cell differentiation on predicting prognosis in OV patients and provides new insights for OV treatment and potential immunotherapeutic strategies.

Stonin 2 activates lysosomal-mTOR axis for cell survival in oral cancer

Aberrant expression of various genes is associated with the progression of oral squamous cell carcinoma. Stonin 2, an endocytic protein, has a prominent role in clathrin-associated endocytosis. Its position in oral cancer is still unknown. Here, we report that STON2 expression increases with an increase in the grade of the oral cancer tissue. Further, STON2 overexpressed cells possess a higher rate of proliferation and migraton in oral cancer cells. STON2 helps maintain lysosomal functions by preserving the lysosomal membrane integrity. It activates the Akt-mTOR axis and retains the mTOR on the membrane of the lysosomes. Further, we have identified an inhibitor of STON2, i.e., Trifluoperazine dihydrochloride (TFP), which targets the lysosomal axis by disrupting the Akt-mTOR pathway and causes lysosomal membrane permeabilization. Intererstingly, TFP shows a decrease in cell vaibility on the oral cancer cells and it was observed that cell viability is restored in TFP-treated STON2 overexpressed cells. Moreover, the lysosomal activity and the Akt-mTOR expression are restored in STON2 overexpressed cells co-treated with TFP, establishing TFP targets STON2 to showcase its anti-cancer effects in oral cancer. In conclusion, STON2 might serve as a potential biomarker in oral cancer, and its inhibition could functions as a novel anti-cancer mechanims against oral cancer.

The prognostic impact of the immune microenvironment in small-cell neuroendocrine carcinoma of the uterine cervix: PD-L1 and immune cell subtypes

Background

We investigate the correlation between programmed cell death-ligand 1 (PD-L1) and tumor-associated immune cell (TAIC) density in small-cell neuroendocrine carcinoma of the uterine cervix (SCNEC) and their correlation with clinicopathologic features.

Methods

PD-L1 and mismatch repair protein (MMR) expression in cancer cells and the density of TAIC were evaluated by immunohistochemistry in 89 SCNEC patients. The combined positive score (CPS), tumor proportion score (TPS), and immune cell score (ICS) of PD-L1 were measured, along with their correlation with clinicopathologic features in SCNEC patients using statistical analyses.

Results

CPS of PD-L1 ≥ 1 was seen in 68.5% of patients, positive TPS and ICS of PD-L1 were detected in 59.6% and 33.7% of patients, respectively. PD-L1CPS was higher in tumor-infiltrating immune cells (r = 0.387, p = 0.001) and positively correlated with programmed cell death-1 and forkhead box P3 + regulatory T cell (FOXP3 + Treg) infiltration (r = 0.443, p < 0.001; r = 0.532, p < 0.001). There was no statistical correlation between PD-L1 and MMR status. PD-L1CPS and PD-L1ICS positivity were independent prognostic factors, correlating with a favorable survival (HR (95%CI) = 0.363(0.139–0.950), p = 0.039 and HR (95% CI) = 0.199(0.050–0.802), p = 0.023, respectively). PD-L1ICS positivity was an independent indicator of recurrence in SCNEC patients and associated with better disease-free survival (HR (95% CI) = 0.124(0.036–0425), p = 0.001). TAIC and MMR levels had no statistical impact on survival results.

Conclusions

PD-L1 positivity was seen in over half of SCNEC tumors. It may work synergistically with FOXP3 + Treg and other infiltrating immune cells to support an adaptive immune response. PD-L1 positivity may be a favorable prognostic factor in SCNEC.

Ultrasound-targeted microbubble destruction-mediated miR-144-5p overexpression enhances the anti-tumor effect of paclitaxel on thyroid carcinoma by targeting STON2

The effects of miR-144-5p and paclitaxel (PTX) on thyroid carcinoma were less explored. Thus, we investigated the effects of miR-144-5p and PTX on thyroid carcinoma. The expression and target gene of miR-144-5p in thyroid carcinoma were analyzed by bioinformatics, y qRT-PCR and dual-luciferase reporter assay. After the transfection mediated by ultrasound-targeted microbubble destruction (UTMD) or liposome, or the treatment of PTX, the viability, proliferation, migration, and invasion of thyroid carcinoma cells were detected by MTT, colony formation, wound-healing, and transwell assays. The expressions of miR-144-5p, STON2, MMP-9, E-cadherin, and N-cadherin in cells were calculated via qRT-PCR or Western blotting. After a subcutaneous-xenotransplant tumor model was established using BALB/c nude mice and further treated with PTX and UTMD-mediated miR-144-5p, the volume, weight, and Ki67 level of tumor were recorded or evaluated by immunohistochemical assays. MiR-144-5p, which was low-expressed in thyroid carcinoma, directly down-regulated STON2 level. MiR-144-5p overexpression and PTX inhibited the viability, proliferation, migration, and invasion of thyroid carcinoma cells, while miR-144-5p silencing caused the opposite results. MiR-144-5p overexpression and PTX further up-regulated E-cadherin level and down-regulated those of MMP-9 and N-cadherin in thyroid carcinoma cells. STON2 overexpression reversed the effects of miR-144-5p overexpression.. MiR-144-5p overexpression enhanced the inhibiting effect of PTX on tumor volume, weight, and Ki67 level of xenotransplant tumor, and the effects of UTMD-mediated miR-144-5p overexpression were stronger than those mediated by liposome. Collectively, UTMD-mediated miR-144-5p overexpression enhanced the anti-tumor effect of PTX on thyroid carcinoma by targeting STON2.

The abnormal expression of chromosomal region maintenance 1 (CRM1)-survivin axis in ovarian cancer and its related mechanisms regulating proliferation and apoptosis of ovarian cancer cells

Ovarian cancer (OC) is the main type of cancer that affects the female reproductive system and has a high morbidity and mortality rate. This study aimed to explore the regulatory effect of the chromosomal region maintenance 1 (CRM1)-survivin axis on the progression of OC. Ovarian cancer cells were transfected with pcDNA3.1-survivin and short hairpin RNA (sh)-CRM1. Cell proliferation was analyzed by cell counting kit-8 (CCK8), 5-ethynyl-2´-deoxyuridine (EdU) staining, and colony formation assays. Apoptosis was detected using flow cytometry. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were performed to analyze the expression of RNA and protein, respectively. qRT-PCR and prognostic correlation analyses revealed that CRM1 is highly expressed in OC cells and related to survival. The results of qRT-PCR, CCK8, colony formation test, EdU staining, flow cytometry, and Western blotting showed that CRM1 silencing inhibited the proliferation and colony formation of OVCAR 3 and SKOV3 cells and promoted cell apoptosis by promoting Caspase-3 activation. Survivin was positively regulated by CRM1 and promoted the development of OC. The results of the rescue experiment showed that overexpression of survivin reversed the inhibitory effect of CRM1 knockdown on the proliferation of ovarian cancer cells and its inhibitory effect on apoptosis. Our findings confirm the role of the CRM1-survivin signal transduction axis in OC by regulating the proliferation and apoptosis of OC cells, and may thus serve as a potential therapeutic target for OC.

Small Extracellular Vesicles from Head and Neck Squamous Cell Carcinoma Cells Carry a Proteomic Signature for Tumor Hypoxia

Tissue hypoxia is commonly observed in head and neck squamous cell carcinomas (HNSCCs), resulting in molecular and functional alterations of the tumor cells. The aim of this study was to characterize tumor-derived small extracellular vesicles (sEVs) released under hypoxic vs. normoxic conditions and analyze their proteomic content. HNSCC cells (FaDu, PCI-30, SCC-25) and HaCaT keratinocytes were cultured in 21, 10, 5, and 1% O₂. sEVs were isolated from supernatants using size exclusion chromatography (SEC) and characterized by nanoparticle tracking analysis, electron microscopy, immunoblotting, and high-resolution mass spectrometry. Isolated sEVs ranged in size from 125-135 nm and contained CD63 and CD9 but not Grp94. sEVs reflected the hypoxic profile of HNSCC parent cells: about 15% of the total detected proteins were unique for hypoxic cells. Hypoxic sEVs expressed a common signature of seven hypoxia-related proteins (KT33B, DYSF, STON2, MLX, LIPA3, NEK5, P12L1) and were enriched in pro-angiogenic proteins. Protein profiles of sEVs reflected the degree of tumor hypoxia and could serve as potential sEV-based biomarkers for hypoxic conditions. Adaptation of HNSCC cells to hypoxia is associated with increased release of sEVs, which are enriched in a unique protein profile. Thus, tumor-derived sEVs can potentially be useful for evaluating levels of hypoxia in HNSCC.

Research Progress in Prognostic Factors and Biomarkers of Ovarian Cancer

Ovarian cancer is a serious threat to women's health; its early diagnosis rate is low and prone to metastasis and recurrence. The current conventional treatment for ovarian cancer is a combination of platinum and paclitaxel chemotherapy based on surgery. The recurrence and progression of ovarian cancer with poor prognosis is a major challenge in treatment. With rapid advances in technology, understanding of the molecular pathways involved in ovarian cancer recurrence and progression has increased, biomarker-guided treatment options can greatly improve the prognosis of patients. This review systematically discusses and summarizes existing and new information on prognostic factors and biomarkers of ovarian cancer, which is expected to improve the clinical management of patients and lead to effective personalized treatment.

Long-chain non-coding RNA GACAT1 promotes development and progression of breast cancer by targeting microRNA-875-3p

Role of long-chain non-coding ribonucleic acid (lncRNA) GACAT1 in the development of breast cancer and its possible mechanism were investigated. The levels of GACAT1, microRNA-875-3p and Stonin2 (STON2) in breast cancer tissues and adjacent normal tissues were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The level of GACAT1 in breast cancer cell lines was further explored. The effects of GACAT1 and microRNA-875-3p on cell proliferation and cycle were detected by cell counting kit-8 (CCK-8) and flow cytometry. The binding relationship between microRNA-875-3p and STON2, microRNA-875-3p and GACAT1 was examined by a dual luciferase reporting assay. It was confirmed by rescue experiments whether GACAT1 canregulate the level of STON2 by binding to microRNA-875-3p. GACAT1 level was clearly enhanced in breast cancer tissues compared to that of the adjacent tissues. Similar result was observed in breast cancer cell lines. Upregulation of GACAT1 promoted the proliferation and cycle of breast cancer cells including MCF-7 and BCap-37. The dual luciferase reporting assay results indicated that GACAT1 had a binding relationship with microRNA-875-3p. Further experiments confirmed that microRNA-875-3p was conspicuously downregulated in breast cancer tissues, and upregulation of microRNA-875-3p could inhibit the proliferation ability of MCF-7 and BCap-37 cells, and partially reversed the promoting effect of GACAT1 on cell cycle. Through bioinformatics prediction and dual luciferase reporter gene experiments, we found that STON2 might be a target gene of microRNA-875-3p. Overexpression of STON2 could partially abolish the effect of microRNA-875-3p on cell proliferation and cycle of MCF-7 and BCap-37 cells. GACAT1 can participate in the progression of breast cancer by promoting the proliferation and cycle of breast cancer cells. The mechanism may be through the regulation of the level of STON2 by adsorbing microRNA-875-3p.

G Protein-Coupled Receptors (GPCRs)-Mediated Calcium Signaling in Ovarian Cancer: Focus on GPCRs activated by Neurotransmitters and Inflammation-Associated Molecules

G-coupled protein receptors (GCPR) involve several signaling pathways, some of them being coupled with intracellular calcium (Ca²⁺) mobilization. GPCRs were involved in migration, invasion and metastasis of different types of cancers, including ovarian cancer. Many studies have discussed the essential contribution of GPCRs activated by steroid hormones in ovarian cancer. However, ovarian cancer is also associated with altered signals coming from the nervous system, the immune system or the inflammatory environment, in which GPCRs are ‘sensing’ these molecular signals. Many studies have been oriented so far on ovarian cell lines (most of them being of human cell lines), and only few studies based on animal models or clinical studies have been devoted to the expression changes or functional role of GPCRs in ovarian cancer. In this paper, we review the alterations of GPCRs activated by neurotransmitters (muscarinic receptors, serotonin receptors, dopamine receptors, adrenoceptors) or inflammation-associated molecules (bradykinin receptors, histamine receptors, chemokine receptors) in ovarian cancer and we discuss their potential as histological biomarkers.

Expression of RRBP1 in epithelial ovarian cancer and its clinical significance

Hematopoietic pre-B cell leukemia transcription factor (PBX)-interacting protein (RRBP1) has been shown to participate in various aspects of malignancies. The clinical significance of RRBP1 and its involvement in the epithelial ovarian cancer have yet to be studied. The aim of the present study was to investigate the expression of RRBP1 in epithelial ovarian cancer (EOC) and its relationship with clinical characteristics and prognosis. We evaluated the mRNA and protein expression levels of RRBP1 by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting (n=45). Immunohistochemistry and data analysis were used to examine the relationship between the expression level of RRBP1 and the clinicopathological features and prognosis of epithelial ovarian cancer. RRBP1 was highly expressed in EOC (P<0.001). The specimens were obtained from 108 patients undergoing surgery to treat epithelial ovarian cancer. RRBP1 expression was obviously related to Federation International of Gynecologie and Obstetrigue (FIGO) stage (P<0.001), histological grade (P=0.021), histological type (P=0.004), and lymph node metastasis (P=0.012) but was not related to patient age (P=0.385) or preoperative carbohydrate antigen125 (CA125) level (P=0.238). Univariate analysis showed that the prognosis of the epithelial ovarian cancer patients was related to the age of the patients, the FIGO stage, and the expression level of RRBP1 (P<0.05). Patients with higher RRBP1 expression had significantly worse overall survival (OS) (P=0.003) and disease-free survival (DFS) (P<0.001). Multivariate survival analysis proved that RRBP1 was an independent predictor of OS (P=0.003) and DFS (P<0.001). RRBP1 plays an important role in predicting the prognosis of EOC. These results show that RRBP1 is a potential target for the treatment of epithelial ovarian cancer.

Nucleolar and spindle associated protein 1 promotes metastasis of cervical carcinoma cells by activating Wnt/β-catenin signaling

Background

The primary obstacle to treat cervical cancer is its high prevalence of metastasis, which severely affects patients’ quality of life and survival time. Nucleolar and spindle associated protein 1 (NUSAP1) has been implicated in the development, progression, and metastasis in several types of cancer. However, its oncogenic role in cervical cancer remains unclear.

Methods

Western blot assay and immunohistochemistry were used to determine the expression of NUSAP1 in 21 clinical fresh Cervical cancer tissues and 233 clinicopathologically characterized cervical cancer specimens. The biological roles of NUSAP1 in the metastasis of cervical cancer were investigated both in vitro by EMT, Side population analysis and Transwell assays and so on, and in vivo using a mouse 4w model of hematogenous metastasis and lymph node metastasis. Bioinformatics analysis, luciferase reporter analysis, immunoprecipitation and immunoblotting of nuclear and cytoplasmic cellular fractions were applied to discern and examine the relationshipbetween NUSAP1 and its potential targets.

Results

The results demonstrated that NUSAP1 was upregulated in cervical cancer cells and tissues, correlated positively with metastasis and poor clinical outcome of patients. High expression of NUSAP1 promoted metastasis by enhancing cancer stem cell (CSC) traits and epithelial-mesenchyme transition (EMT) progression, while silencing of NUSAP1 reduced CSC traits and EMT progression. Mechanistically, upregulation of NUSAP1 induced SUMOylation of TCF4 via interacting with SUMO E3 ligase Ran-binding protein 2 (RanBP2) and hyperactivated Wnt/β-catenin signaling in cervical cancer cells. Additionally, NUSAP1-induced cervical cancer cells metastasis and the cancer stem cell phenotype were abrogated with the Wnt/β-catenin signaling inhibitor XAV-939 treatment. Importantly, co-therapy of conventional treatment and XAV-939 will provide a novel and effective treatment for NUSAP1-ovexpressed cervical cancer patients.

Conclusions

Our results demonstrate thatNUSAP1 upregulation contributes to metastasis of cervical cancer by promoting CSC properties and EMT via Wnt/β-catenin signaling and XAV-939 might serve as a potential tailored therapeutic option for patients with NUSAP1-ovexpressed cervical cancer.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1037-y) contains supplementary material, which is available to authorized users.

STON2 negatively modulates stem-like properties in ovarian cancer cells via DNMT1/MUC1 pathway

Background

Cancer stem cells (CSCs) possess abilities of self-renewal and differentiation, have oncogenic potential and are regarded to be the source of cancer recurrence. However, the mechanism by which CSCs maintain their stemness remains largely unclear.

Methods

In this study, the cell line-derived ovarian CSCs (OCSCs), 3AO and Caov3, were enriched in serum-free medium (SFM). Differentially expressed proteins were compared between the OCSC subpopulation and parental cells using liquid chromatography (LC)-mass spectrometry (MS)/MS label-free quantitative proteomics. Sphere-forming ability assays, flow cytometry, quantitative real-time polymerase chain reaction (qPCR), western blotting, and in vivo xenograft experiments were performed to evaluate stemness. RNA-sequencing (RNA-seq) and pyrosequencing were used to reveal the mechanism by which STON2 negatively modulates the stem-like properties of ovarian cancer cells.

Results

Among the 74 most differentially expressed proteins, stonin 2 (STON2) was confirmed to be down-regulated in the OCSC subpopulation. We show that STON2 negatively modulates the stem-like properties of ovarian cancer cells, which are characterized by sphere formation, a CD44⁺CD24⁻ ratio, and by CSC- and epithelial mesenchymal transition (EMT)-related markers. STON2 knockdown also accelerated tumorigenesis in NOD/SCID mice. Further investigation revealed a downstream target, mucin 1 (MUC1), as up-regulated upon the down regulation of STON2. A decrease in both DNA methyltransferase 1 (DNMT1) expression and methylation in the promoter region of MUC1 was associated with subsequently elevated MUC1 expression, as detected in STON2 knockdown in 3AO and Caov3 cells. Direct DNMT1 knockdown simultaneously elevated MUC1 expression. The functional significance of this STON2-DNMT1/MUC1 pathway is supported by the observation that STON2 overexpression suppresses MUC1-induced sphere formation of OCSCs. The paired expression of STON2 and MUC1 in ovarian cancer specimens was also detected revealing the prognostic value of STON2 expression to be highly dependent on MUC1 expression.

Conclusions

Our results imply that STON2 may negatively regulate stemness in ovarian cancer cells via DNMT1-MUC1 mediated epigenetic modification. STON2 is therefore involved in OCSC biology and may represent a therapeutic target for innovative treatments aimed at ovarian cancer eradication.

Electronic supplementary material

The online version of this article (10.1186/s13046-018-0977-y) contains supplementary material, which is available to authorized users.

miR-199b-5p-Stonin 2 axis regulates metastases and epithelial-to-mesenchymal transition of papillary thyroid carcinoma

Papillary thyroid carcinoma is one of the most fatal malignant endocrine tumors, and the prognosis remains poor because of the lack of effective therapeutic targets. In this study, we demonstrated that the level of miR-199b-5p was markedly downregulated in papillary thyroid carcinoma. The ectopic expression level of miR-199b-5p in papillary thyroid carcinoma cell B-CPAP could inhibit growth, migration, and invasion as well as epithelial-mesenchymal transition (EMT) and decreased cell metastasis in vivo, but silencing miR-199b-5p caused a contradictory outcome. Additionally, Stonin 2 (STON2) was identified as a direct target gene of miR-199b-5p. Consistent with the downregulation of miR-199b-5p, the overexpression of STON2 induced the growth, migration and invasion of B-CPAP cells. It was also demonstrated that miR-199b-5p suppressed papillary thyroid carcinoma cell aggressiveness by targeting STON2. Furthermore, the overexpression of miR-199b-5p inhibited cell proliferation, promoted apoptosis, and increased the chemo-sensitivity of thyroid carcinoma B-CPAP cells toward the chemotherapy drug paclitaxel. Finally, in vivo experiments further demonstrated that miR-199b-5p suppressed tumor growth in nude mice. Thus, this study revealed that miR-199b-5p functions as antioncogene miRNA in papillary thyroid carcinoma cells and that the miR-199b-5p/STON2 axis might be a potential treatment option for papillary thyroid carcinoma. © 2018 IUBMB Life, 71(1):28-40, 2019.

LncSOX4 serves an oncogenic role in the tumorigenesis of epithelial ovarian cancer by promoting cell proliferation and inhibiting apoptosis

Epithelial ovarian cancer is one of the primary causes of gynecological cancer mortality. Increasing evidence has suggested that long non-coding RNAs (lncRNAs) may serve a pivotal role in cancer development. To determine whether Lnc SRY-box 4 (SOX4), an lncRNA, promotes the self-renewal of liver tumor cells and contributes to the development of epithelial ovarian cancer, the present study investigated the expression of LncSOX4 in clinical epithelial ovarian cancer tissues and non-cancer controls by reverse transcription-quantitative polymerase chain reaction analysis. In addition, siRNA targeting LncSOX4 was designed and transfected into epithelial ovarian cancer cells to further assess the effect of knocking out LncSOX4 on cellular apoptosis, cell viability, proliferation and the cell cycle. The results demonstrated that the LncSOX4 expression level was significantly upregulated in epithelial ovarian cancer tissues (3.98 vs. 1.71, P<0.001). Silencing LncSOX4 in the SKOV3 and OVCAR3 cell lines significantly impaired cell proliferation (P<0.001). Cell cycle assays revealed that the proportion of cells in the G0/G1 phase increased significantly, whereas those in the S phase and G2/M phase decreased. Apoptosis rate additionally increased following knockdown of LncSOX4 in the two cell lines. Furthermore, it was observed that an increased LncSOX4 expression level was positively associated with larger tumor sizes, more advanced tumor grade and more distant metastases.