STK39, overexpressed in osteosarcoma, regulates osteosarcoma cell invasion and proliferation

Decreasing of serine/threonine kinase 39 has tumour inhibiting effects on acute myeloid leukaemia by impacting the PI3K/AKT and Wnt/β-catenin signalling cascades

Serine/threonine kinase 39 (STK39) has been identified as a key regulator of tumour progression. However, whether STK39 plays a role in acute myeloid leukaemia (AML) remains undetermined. This work explored the expression and functions of STK39 in AML. STK39 was found to be overexpressed in AML and was negatively correlated with overall survival. Functionally, silencing STK39 inhibited cell proliferation, promoted cell differentiation and induced cell cycle arrest and apoptosis. The tumour inhibiting effects of STK39 downregulation were also verified by an in vivo xenograft tumour assay. Mechanistically, STK39 was closely related to the PI3K/AKT and Wnt/β-catenin signalling cascades in AML. Silencing of STK39 had suppressive effects on the PI3K/AKT and Wnt/β-catenin signalling cascades. The suppressive effect of STK39 silencing on the Wnt/β-catenin signalling cascade was significantly reversed when PI3K/AKT was reactivated. When β-catenin was re-expressed, the tumour-inhibiting effects caused by STK39 silencing were significantly eliminated. Therefore, STK39 plays a crucial role in AML and could be targeted for potential therapeutic purposes in treating AML.

Cross-border regulation of the STK39/MAPK14 pathway by Lycium barbarum miR166a to inhibit triple-negative breast cancer

OBJECTIVE

To investigate the effects of Lycium barbarum miRNA166a (Lb-miR166a) on human gene expression regulation during the therapy for triple-negative breast cancer (TNBC).

METHODS

Transcriptome sequencing was used to analyze the distribution and composition of miRNA in Lycium barbarum fruit. Lb-miR166a was introduced into TNBC MB-231 cells by lentiviral transfection to study its effects on cell proliferation, apoptosis, invasion, and metastasis both in vivo and in vitro. Bioinformatic and dual-luciferase assays identified the target gene of Lb-miR166a. The role of STK39 in TNBC progression was elucidated through clinical data analysis combined with cellular studies. The influence of Lb-miR166a on the STK39/MAPK14 pathway was confirmed using a target-specific knockout MB-231 cell line.

RESULTS

Lb-miR166a was found to be highly expressed in Lycium barbarum. It inhibited MB-231 cell proliferation, invasion, and metastasis, and promoted apoptosis. STK39 was overexpressed in TNBC and was associated with increased invasiveness and poorer patient prognosis. Gene enrichment analysis and dual-luciferase assays demonstrated that Lb-miR166a regulates STK39 expression cross-border and inhibits MAPK14 phosphorylation, impacting the phosphorylation of downstream target genes.

CONCLUSION

The downregulation of STK39 and subsequent inhibition of MAPK14 phosphorylation by Lb-miR166a leads to reduced proliferation, migration, and invasion of TNBC cells. These findings suggest a novel therapeutic strategy for TNBC treatment, highlighting possible clinical applications of Lb-miR166a in managing this aggressive cancer type.

The mutational landscape of a US Midwestern breast cancer cohort reveals subtype-specific cancer drivers and prognostic markers

BACKGROUND

Female breast cancer remains the second leading cause of cancer-related death in the USA. The heterogeneity in the tumor morphology across the cohort and within patients can lead to unpredictable therapy resistance, metastasis, and clinical outcome. Hence, supplementing classic pathological markers with intrinsic tumor molecular markers can help identify novel molecular subtypes and the discovery of actionable biomarkers.

METHODS

We conducted a large multi-institutional genomic analysis of paired normal and tumor samples from breast cancer patients to profile the complex genomic architecture of breast tumors. Long-term patient follow-up, therapeutic regimens, and treatment response for this cohort are documented using the Breast Cancer Collaborative Registry. The majority of the patients in this study were at tumor stage 1 (51.4%) and stage 2 (36.3%) at the time of diagnosis. Whole-exome sequencing data from 554 patients were used for mutational profiling and identifying cancer drivers.

RESULTS

We identified 54 tumors having at least 1000 mutations and 185 tumors with less than 100 mutations. Tumor mutational burden varied across the classified subtypes, and the top ten mutated genes include MUC4, MUC16, PIK3CA, TTN, TP53, NBPF10, NBPF1, CDC27, AHNAK2, and MUC2. Patients were classified based on seven biological and tumor-specific parameters, including grade, stage, hormone receptor status, histological subtype, Ki67 expression, lymph node status, race, and mutational profiles compared across different subtypes. Mutual exclusion of mutations in PIK3CA and TP53 was pronounced across different tumor grades. Cancer drivers specific to each subtype include TP53, PIK3CA, CDC27, CDH1, STK39, CBFB, MAP3K1, and GATA3, and mutations associated with patient survival were identified in our cohort.

CONCLUSIONS

This extensive study has revealed tumor burden, driver genes, co-occurrence, mutual exclusivity, and survival effects of mutations on a US Midwestern breast cancer cohort, paving the way for developing personalized therapeutic strategies.

The Ubiquitin-Proteasome System Participates in Sperm Surface Subproteome Remodeling during Boar Sperm Capacitation

Sperm capacitation is a complex process endowing biological and biochemical changes to a spermatozoon for a successful encounter with an oocyte. The present study focused on the role of the ubiquitin-proteasome system (UPS) in the remodeling of the sperm surface subproteome. The sperm surface subproteome from non-capacitated and in vitro capacitated (IVC) porcine spermatozoa, with and without proteasomal inhibition, was selectively isolated. The purified sperm surface subproteome was analyzed using high-resolution, quantitative liquid chromatography-mass spectrometry (LC-MS) in four replicates. We identified 1680 HUGO annotated proteins, out of which we found 91 to be at least 1.5× less abundant (p < 0.05) and 141 to be at least 1.5× more abundant (p < 0.05) on the surface of IVC spermatozoa. These proteins were associated with sperm capacitation, hyperactivation, metabolism, acrosomal exocytosis, and fertilization. Abundances of 14 proteins were found to be significantly different (p < 0.05), exceeding a 1.5-fold abundance between the proteasomally inhibited (100 µM MG132) and vehicle control (0.2% ethanol) groups. The proteins NIF3L1, CSE1L, NDUFB7, PGLS, PPP4C, STK39, and TPRG1L were found to be more abundant; while BPHL, GSN, GSPT1, PFDN4, STYXL1, TIMM10, and UBXN4 were found to be less abundant in proteasomally inhibited IVC spermatozoa. Despite the UPS having a narrow range of targets, it modulated sperm metabolism and binding by regulating susceptible surface proteins. Changes in CSE1L, PFDN4, and STK39 during in vitro capacitation were confirmed using immunocytochemistry, image-based flow cytometry, and Western blotting. The results confirmed the active participation of the UPS in the extensive sperm surface proteome remodeling that occurs during boar sperm capacitation. This work will help us to identify new pharmacological mechanisms to positively or negatively modulate sperm fertilizing ability in food animals and humans.

Quantitative proteomics analysis in small cell carcinoma of cervix reveals novel therapeutic targets

BACKGROUND

As a rare pathologic subtype, small cell carcinoma of the cervix (SCCC) is characterized by extensive aggressiveness and resistance to current therapies. To date, our knowledge of SCCC origin and progression is limited and sometimes even controversial. Herein, we explored the whole-protein expression profiles in a panel of SCCC cases, aiming to provide more evidence for the precise diagnosis and targeting therapy.

METHODS

Eighteen SCCC samples and six matched normal cervix tissues were collected from January 2013 to December 2017. Data independent acquisition mass spectrometry (DIA) was performed to discriminate the different proteins (DEPs) associated with SCCC. The expression of CDN2A and SYP in corresponding SCCC tissues was verified using immunohistochemistry. GO and KEGG enrichment analyses were used to identify the key DEPs related to SCCC development and tumor recurrence.

RESULTS

As a result, 1311 DEPs were identified in SCCC tissues (780 up-regulated and 531 down-regulated). In up-regulated DEPs, both GO analysis and KEGG analysis showed the most enriched were related to DNA replication (including nuclear DNA replication, DNA-dependent DNA replication, and cell cycle DNA replication), indicating the prosperous proliferation in SCCC. As for the down-regulated DEPs, GO analysis showed that the most enriched functions were associated with extracellular matrix collagen-containing extracellular matrix. KEGG analysis revealed that the DEPs were enriched in Complement and coagulation cascades, proteoglycans in cancer, and focal adhesion-related pathways. Down-regulation of these proteins could enhance the mobility of cancer cells and establish a favorable microenvironment for tumor metastasis, which might be accounted for the frequent local and distant metastasis in SCCC. Surprisingly, the blood vessels and circulatory system exhibit a down-regulation in SCCC, which might be partly responsible for its resistance to anti-angiogenic regimens. In the stratification analysis of early-stage tumors, a group of enzymes involved in the cancer metabolism was discriminated in these recurrence cases.

CONCLUSIONS

Using quantitative proteomics analysis, we first reported the whole-protein expression profiles in SCCC. Significant alterations were found in proteins associated with the enhancement of DNA replication and cellular motility. Besides the association with mitosis, a unique metabolic feature was detected in cases with tumor recurrence. These findings provided novel targets for disease surveillance and treatments, which warranted further validation in the future.

Gut microbiota-induced microRNA-206-3p increases anxiety-like behaviors by inhibiting expression of Cited2 and STK39

BACKGROUND

Anxiety disorder is highly prevalent worldwide and represents a chronic and functionally disabling condition, with high levels of psychological stress characterized by cognitive and physiological symptoms. The purpose of this study is to evaluate the clinical significance of gut microbiota regulating microRNA (miR)-206-3p as a biomarker in the anxiety-like behaviors.

METHODS

Initially, bioinformatics analysis was performed to predict the related factors for gut microbiota affecting anxiety-like behaviors. Next, the anxiety-like behaviors in mice were measured by multiple experiments. Western blot analysis, immunohistochemistry, and enzyme-linked immunosorbent assay (ELISA) were utilized to measure the levels of 5-hydroxytryptamine (5-HT), brain derived neurotrophic factor (BDNF), and neutrophil expressed (NE) in brain tissues and serum and cAMP responsive element binding protein 1 (CREB) phosphorylation in brain tissues of germ-free (GF) mice. Dual-luciferase reporter gene assay was employed to verify the relationship between miR-206-3p and Cbp/p300 interacting transactivator with Glu/Asp rich carboxy-terminal domain 2 (Cited2)/serine/threonine kinase 39 (STK39). Ectopic expression and depletion experiments of miR-206-3p were conducted to determine the expression of miR-206-3p and mRNA and protein levels of Cited2, and STK39 in HT22 cells and brain tissues. Finally, transmission electron microscope (TEM) was used to observe the effects of miR-206-3p on hippocampal mitochondria and synapses.

RESULTS

Gut microbiota could elevate miR-206-3p expression in brain tissues to increase the anxiety-like behaviors. GF mice displayed the increased levels of 5-HT, BDNF, and NE in brain tissues and serum and CREB phosphorylation in brain tissues. Cited2/STK39 was identified as the target genes of miR-206-3p. Upregulated miR-206-3p increased anxiety-like behaviors by promoting degeneration of mitochondria and synapses in hippocampus via downregulation of Cited2 and STK39.

CONCLUSIONS

In conclusion, the key findings of the current study demonstrate that gut microbiota aggravated anxiety-like behaviors via the miR-206-3p/Cited2/STK39 axis.

Classifying Integrated Signature Molecules in Macrophages of Rheumatoid Arthritis, Osteoarthritis, and Periodontal Disease: An Omics-Based Study

Rheumatoid arthritis (RA), osteoarthritis (OA), and periodontal disease (PD) are chronic inflammatory diseases that are globally prevalent, and pose a public health concern. The search for a potential mechanism linking PD to RA and OA continues, as it could play a significant role in disease prevention and treatment. Recent studies have linked RA, OA, and PD to Porphyromonas gingivalis (PG), a periodontal bacterium, through a similar dysregulation in an inflammatory mechanism. This study aimed to identify potential gene signatures that could assist in early diagnosis as well as gain insight into the molecular mechanisms of these diseases. The expression data sets with the series IDs GSE97779, GSE123492, and GSE24897 for macrophages of RA, OA synovium, and PG stimulated macrophages (PG-SM), respectively, were retrieved and screened for differentially expressed genes (DEGs). The 72 common DEGs among RA, OA, and PG-SM were further subjected to gene–gene correlation analysis. A GeneMANIA interaction network of the 47 highly correlated DEGs comprises 53 nodes and 271 edges. Network centrality analysis identified 15 hub genes, 6 of which are DEGs (API5, ATE1, CCNG1, EHD1, RIN2, and STK39). Additionally, two significantly up-regulated non-hub genes (IER3 and RGS16) showed interactions with hub genes. Functional enrichment analysis of the genes showed that “apoptotic regulation” and “inflammasomes” were among the major pathways. These eight genes can serve as important signatures/targets, and provide new insights into the molecular mechanism of PG-induced RA, OA, and PD.

MiR-223-3p-loaded exosomes from bronchoalveolar lavage fluid promote alveolar macrophage autophagy and reduce acute lung injury by inhibiting the expression of STK39

This study investigated the molecular mechanism by which bronchoalveolar lavage fluid exosomes (BALF-exo) alleviated acute lung injury (ALI). BALF-exo was isolated from mice. LPS was used to induce inflammation in rat alveolar macrophages (NR8383). NR8383 cell models were treated with BALF-exo or BALF-exo loaded with miR-223-3p mimics/inhibitors, or STK39 was overexpressed in NR8383 cells before LPS and BALF-exo treatment. These cells were subjected to apoptosis, autophagy, and inflammation assays. RNA immunoprecipitation and dual-luciferase reporter assay were conducted to verify the binding between miR-223-3p and STK39. LPS-induced ALI mouse models were treated with BALF-exo loaded with miR-223-3p mimics. miR-223-3p was lowly expressed in BALF-exo from LPS-treated mice. BALF-exo loaded with miR-223-3p mimics increased viability and autophagy and decreased apoptosis and inflammation in NR8383 cell models. Inhibition of miR-223-3p in BALF-exo or overexpression of STK39 in NR8383 cells repressed the therapeutic effect of BALF-exo in LPS-treated NR8383 cells. STK39 was a target gene of miR-223-3p. miR-223-3p shuttled by BALF-exo negatively regulated the expression of STK39 in NR8383 cells. BALF-exo loaded with miR-223-3p mimics also reduced lung injuries in ALI mice. In conclusion, miR-223-3p loaded in BALF-exo alleviates ALI by targeting STK39 in alveolar macrophages.

Genetic correlation between thyroid hormones and Parkinson's disease

Parkinson’s disease (PD) was reported to be connected with thyroid diseases clinically, which might be a critical clew to immune pathogenesis of PD. However, there was no further research to study the pathogenesis correlation between PD and thyroid diseases. In this study, except for investigating the difference in thyroid hormone between PD and the control group, we explored genetic correlation between thyroid and PD. We tried to find their shared molecular pathway by analyzing the effect of PD risk genes on thyroid function. Interestingly, most of those 12 meaningful SNPs we found could affect PD and thyroid function through immune mechanism, which is consistent with our original conjecture and provides significant evidence for the immune pathogenesis of PD.

Transcription factor specificity protein 1-mediated Serine/threonine kinase 39 upregulation promotes the proliferation, migration, invasion and epithelial-mesenchymal transition of hepatocellular carcinoma cells by activating the transforming growth factor-β1 /Smad2/3 pathway

Bioinformatics analysis showed that Serine/threonine kinase 39 (STK39), which was testified to play an important role in human cancers, may be a hub gene in diagnosing hepatocellular carcinoma (HCC). This study aimed to explore whether STK39 could be regulated by specificity protein 1 (SP1) to affect HCC cells malignant processes. Firstly, STK39 expression in tissues of HCC patients and several cell lines was analyzed. After STK39 silencing, cell proliferation was evaluated by methyl thiazolyl tetrazolium and colony formation assay. Tunel staining was used to detect cell apoptosis. Then, the abilities of cell migration and invasion were determined with wound healing and transwell assays. The expression of epithelial-mesenchymal transition (EMT)-related proteins and transforming growth factor-β1 (TGF-β1)/Smad2/3 pathway proteins was tested by western blot analysis. Thereafter, cells were overexpressed with SP1 under the circumstance of STK39 knockdown, and then the above cellular processes were under observation. Results revealed that the increased expression of STK39, which was found in both HHC patients and HCC cell lines, exhibited poor HCC prognosis. STK39 silencing inhibited Hep3b cell proliferation, migration, invasion, EMT and TGF-β1/Smad2/3 expression but promoted cell apoptosis. Additionally, SP1 could bind to the STK39 promoter and facilitate STK39 expression. Further studies revealed that the effects of STK39 silencing on Hep3b cells were blocked by SP1 overexpression. In conclusion, SP1-mediated STK39 up-regulation leads to the increased proliferation, migration, invasion and EMT of HCC cells via activating TGF-β1/Smad2/3 pathway. Therapies that target SP1 to knockdown STK39 expression may contribute to the inhibition of HCC progression.

Knockdown of long non-coding RNA CDKN2B-AS1 suppresses the progression of breast cancer by miR-122-5p/STK39 axis

The lncRNAs have been made certain to take part in the development of most cancers in multiple ways. Here, our purpose is to making observation of the biological role and function of lncRNA CDKN2B-AS1 in human breast cancer. Twenty-eight pairs of breast cancer tissue and adjacent normal tissue from breast cancer patients were used to investigate the expression of CDKN2B-AS1 by qRT-PCR. And a lentivirus-shRNA guided CDKN2B-AS1 were to reduce its expression. The function of CDKN2B-AS1 was analyzed using a series of in vitro assays. Meanwhile, the xenograft model was used to further explicate the role of CDKN2B-AS1 in breast cancer. As for the results, there is a relative rich expression of CDKN2B-AS1 in breast cancer tissues compared with the corresponding adjacent normal tissues. Compared with the human breast epithelial cell line, the abundant expression of CDKN2B-AS1 in breast cancer cells were revealed as well. Then, knockdown CDKN2B-AS1 inhibited the malignant biological behaviors of MCF7 and T47D cells. In mechanism, CDKN2B-AS1 sponged the miR-122-5p to regulate STK39 expression. Furthermore, the inhibition effect with sh-CDKN2B-AS1 on breast cancer cells was alleviated by miR-122-5p inhibitor. Last, an in vivo model also confirmed that knockdown CDKN2B-AS1 retarded the growth of breast cancer. Our data concluded that knockdown of CDKN2B-AS1 suppresses the progression of breast cancer by miR-122-5p/STK39 axis.

STK39 enhances the progression of Cholangiocarcinoma via PI3K/AKT pathway

Serine/threonine kinase 39 (STK39) is overexpressed in various tumor tissues and plays an essential role in tumor progression. In this study, we investigated the clinical value, as well as the potential functions and mechanisms of STK39 in cholangiocarcinoma (CCA). The results showed that STK39 was overexpressed in CCA and negatively associated with the prognosis of patients with CCA. Functionally, STK39 knockdown suppressed cell proliferation, migration, and invasion, while STK39 overexpression facilitated tumor aggressiveness. The tumor-promoting effects of STK39 in CCA were also validated by in vivo experiments. Mechanistically, RNA-seq analysis identified that STK39 enhanced the progression of CCA by activating PI3K/AKT signaling pathway. Furthermore, overexpression of STK39 could induce gemcitabine resistance in CCA cells. Moreover, the increased expression of STK39 may be mediated by the dysregulation of miR-26a-5p. In summary, STK39 could be served as a valuable prognostic candidate and a potential therapeutic target of CCA.

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STK39 was overexpressed in CCA, negatively associated with the prognosis of patients with CCA

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STK39 knockdown suppressed cell proliferation and invasion. STK39 overexpression facilitated tumor aggressiveness

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STK39 mediates oncogenic effects on CCA cells by activating the PI3K/AKT signaling pathway

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STK39 reduces CCA sensitivity to gemcitabine. Increased expression of STK39 may be mediated by dysregulation of miR-26a-5p

CircPTK2 Suppresses the Progression of Gastric Cancer by Targeting the MiR-196a-3p/AATK Axis

Background

Gastric cancer is a type of malignant tumor with high morbidity and mortality. It has been shown that circular RNAs (circRNAs) exert critical roles in gastric cancer progression via working as microRNA (miRNA) sponges to regulate gene expression. However, the role and potential molecular mechanism of circRNAs in gastric cancer remain largely unknown.

Methods

CircPTK2 (hsa_circ_0005273) was identified by bioinformatics analysis and validated by RT-qPCR assay. Bioinformatics prediction, dual-luciferase reporter, and RNA pull-down assays were used to determine the interaction between circPTK2, miR-196a-3p, and apoptosis-associated tyrosine kinase 1 (AATK).

Results

The level of circPTK2 was markedly downregulated in gastric cancer tissues and gastric cancer cells. Upregulation of circPTK2 significantly suppressed the proliferation, migration, and invasion of gastric cancer cells, while circPTK2 knockdown exhibited opposite effects. Mechanically, circPTK2 could competitively bind to miR-196a-3p and prevent miR-196a-3p to reduce the expression of AATK. In addition, overexpression of circPTK2 inhibited tumorigenesis in a xenograft mouse model of gastric cancer.

Conclusion

Collectively, circPTK2 functions as a tumor suppressor to suppress gastric cancer cell proliferation, migration, and invasion through regulating the miR-196a-3p/AATK axis, suggesting that circPTK2 may serve as a novel therapeutic target for gastric cancer.

Knockdown of STK39 suppressed cell proliferation, migration, and invasion in hepatocellular carcinoma by repressing the phosphorylation of mitogen-activated protein kinase p38

Hepatocellular carcinoma (HCC) is a serious malignant tumor of the liver. It has been reported that serine/threonine kinase 39 (STK39) participates in tumorigenesis. However, the role of STK39 in HCC remains unknown. In this study, the qRT-PCR and western blot assay demonstrated that STK39 expression was enhanced in HCC patients and tissues. Moreover, CCK-8 and colony formation assays confirmed that knockdown of STK39 suppressed SK-HEP-1 and Huh7 cells proliferation. Furthermore, wound healing assay and transwell assay revealed that knockdown of STK39 repressed SK-HEP-1 and Huh7 cells migration and invasion. Interestingly, knockdown of STK39 reduced p-p38/p38 ratio and levels of c-Myc. Consistently, knockdown of STK39 inhibited the HCC tumor growth in vivo. In summary, knockdown of STK39 suppressed the proliferation, migration, and invasion of HCC cells by inducing the lower levels of p-p38, which might provide a novel therapeutic target for HCC.

STK39 promotes breast cancer invasion and metastasis by increasing SNAI1 activity upon phosphorylation

SNAI1 is widely regarded as a master driver of epithelial-mesenchymal transition (EMT) and associated with breast cancer progression and metastasis. This pro-malignant role is strongly linked to posttranslational modification, especially phosphorylation, which controls its protein levels and subcellular localization. While multiple kinases are implicated in regulation of SNAI1 stability, the precise mechanism by which SNAI1 is stabilized in tumors remains to be fully elucidated.

Methods: A series of in vitro and in vivo experiments were conducted to reveal the regulation of SNAI1 by Serine/Threonine Kinase 39 (STK39) and the role of STK39 in breast cancer metastasis.

Results: We identified STK39, a member of Stem 20-like serine/threonine kinase family, as a novel posttranslational regulator that enhances the stability of SNAI1. Inhibition of STK39 via knockdown or use of a specific inhibitor resulted in SNAI1 destabilization. Mechanistically, STK39 interacted with and phosphorylated SNAI1 at T203, which is critical for its nuclear retention. Functionally, STK39 inhibition markedly impaired the EMT phenotype and decreased tumor cell migration, invasion, and metastasis both in vitro and in vivo. These effects were rescued by ectopic SNAI1 expression. In addition, depletion of STK39 dramatically enhanced sensitivity to chemotherapeutic agents.

Conclusions: Our study demonstrated that STK39 is a key mediator of SNAI1 stability and is associated with the pro-metastatic cellular process, highlighting the STK39-SNAI1 signaling axis as promising therapeutic targets for treatments of metastatic breast cancer.

STK39 is a novel kinase contributing to the progression of hepatocellular carcinoma by the PLK1/ERK signaling pathway

Rationale: Protein kinases are critical therapeutic targets for curing hepatocellular carcinoma (HCC). As a serine/threonine kinase, the potential roles of serine/threonine kinase 39 (STK39) in HCC remain to be explored. Methods: The expression of STK39 was examined by RT-qPCR, western blotting and immunohistochemistry. Cell proliferation and apoptosis were detected by CCK8 and TUNEL kit. Cell migration and invasion assays were performed using a transwell system with or without Matrigel. RNA-seq, mass spectrometry and luciferase reporter assays were used to identify STK39 binding proteins. Results: Here, we firstly report that STK39 was highly overexpressed in clinical HCC tissues compared with adjacent tissues, high expression of STK39 was induced by transcription factor SP1 and correlated with poor patient survival. Gain and loss of function assays revealed that overexpression of STK39 promoted HCC cell proliferation, migration and invasion. In contrast, the depletion of STK39 attenuated the growth and metastasis of HCC cells. Moreover, knockdown of STK39 induced the HCC cell cycle arrested in the G2/M phase and promoted apoptosis. In mechanistic studies, RNA-seq revealed that STK39 positively regulated the ERK signaling pathway. Mass spectrometry identified that STK39 bound to PLK1 and STK39 promoted HCC progression and activated ERK signaling pathway dependent on PLK1. Conclusions: Thus, our study uncovers a novel role of STK39/PLK1/ERK signaling axis in the progress of HCC and suggests STK39 as an indicator for prognosis and a potential drug target of HCC.

RNA-seq Profiling and Co-expression Network Analysis of Long Noncoding RNAs and mRNAs Reveal Novel Pathogenesis of Noise-induced Hidden Hearing Loss

Noise-induced hidden hearing loss (NIHHL), one of the family of conditions described as noise-induced hearing loss (NIHL), is characterized by synaptopathy following moderate noise exposure that causes only temporary threshold elevation. Long noncoding RNAs (lncRNAs) mediate several essential regulatory functions in a wide range of biological processes and diseases, but their roles in NIHHL remain largely unknown. In order to determine the potential roles of these lncRNAs in the pathogenesis of NIHHL, we first evaluated their expression in NIHHL mice model and mapped possible regulatory functions and targets using RNA-sequencing (RNA-seq). In total, we identified 133 lncRNAs and 522 mRNAs that were significantly dysregulated in the NIHHL model. Gene Ontology (GO) showed that these lncRNAs were involved in multiple cell components and systems including synapses and the nervous and sensory systems. In addition, a lncRNA-mRNA network was constructed to identify core regulatory lncRNAs and transcription factors. KEGG analysis was also used to identify the potential pathways being affected in NIHHL. These analyses allowed us to identify the guanine nucleotide binding protein alpha stimulating (GNAS) gene as a key transcription factor and the adrenergic signaling pathway as a key pathway in the regulation of NIHHL pathogenesis. Our study is the first, to our knowledge, to isolate a lncRNA mediated regulatory pathway associated with NIHHL pathogenesis; these observations may provide fresh insight into the pathogenesis of NIHHL and may pave the way for therapeutic intervention in the future.

Identification of Hub Genes in Hepatocellular Carcinoma Related to Progression and Prognosis by Weighted Gene Co-Expression Network Analysis

BACKGROUND Hepatocellular carcinoma (HCC) is one of the most prevalent cancers in the world. Bioinformatics studies have been widely used for screening genes involved in the initiation and progression of HCC. MATERIAL AND METHODS We obtained liver cancer microarray raw data from the GEO database (GSE54238). Next, weighted gene co-expression network analysis (WGCNA) was used to assess the critical modules. Then, we assessed the gene significance by calculating survival, expression level, and receiver operating characteristic (ROC) in the TCGA database. We also validated the expression of selected genes in the Oncomine database and calculated the relationship between 4 hub genes and immune infiltration. Finally, GSEA enrichment analysis was used to explore the potential mechanism. RESULTS We identified the red and blue modules as the critical modules, and found 176 candidate genes by assessing gene significance. GO and KEEG results suggested that the candidate genes are involved in the cell cycle. Four hub genes - SOX4, STK39, TARBP1, and TDRKH - were eventually screened after validating their expression and power in diagnosing HCC in the TCGA database. Immune infiltration analysis and GSEA enrichment analysis showed that these 4 hub genes were correlated with the immune cell populations infiltration and that multiple mechanisms were involved, such as angiogenesis and epithelial-mesenchymal transition. CONCLUSIONS Our findings revealed that these 4 genes can be regarded as potential prognosticators and therapeutic targets for HCC.

MicroRNA‑299‑5p inhibits cell metastasis in breast cancer by directly targeting serine/threonine kinase 39

Numerous studies have demonstrated that microRNAs (miRNAs) play a key role in human carcinogenesis and metastasis. For example, miR‑299‑5p has previously been revealed to be dysregulated in several human cancers. However, the biological function of miR‑299‑5p in breast cancer remains unclear. The present study demonstrated that miR‑299‑5p was downregulated in breast cancer tissues and cell lines. The restoration of miR‑299‑5p expression suppressed cell migration and invasion, whereas inhibition of miR‑299‑5p promoted cell migration and invasion. In addition, in vivo studies demonstrated that miR‑299‑5p overexpression was able to inhibit tumour metastasis in nude mice. Mechanistically, through bioinformatics analysis and a dual‑luciferase assay, it was confirmed that miR‑299‑5p directly targets serine/threonine kinase 39 (STK39). Silencing STK39 inhibited cell metastasis and suppressed epithelial‑mesenchymal transition markers and matrix metalloproteinase expression, whereas restoration of STK39 expression was able to reverse miR‑299‑5p‑inhibited cell migration and invasion. Collectively, the results of the present study demonstrated that miR‑299‑5p supresses breast cancer cell migration and invasion by targeting STK39. These findings may provide novel insights into miR‑299‑5p and its potential diagnostic and therapeutic benefits in breast cancer.

Diallyl disulfide suppresses FOXM1-mediated proliferation and invasion in osteosarcoma by upregulating miR-134

Diallyl disulfide (DADS), a volatile component of garlic oil, exerts anticancer activity in various types of cancers, while its anticancer effects against osteosarcoma (OS) have not been previously explored. This study aimed to investigate the anticancer potential of DADS in OS and to explore the underlying mechanisms. DADS reduced the cell viability and increased the expression of miR-134 in OS cell lines, and this effect was in a time- and concentration-dependent manner. Furthermore, in vitro functional assays revealed that DADS significantly inhibited the proliferation and invasion of human OS U2OS and MG-63 cells, which was partially reversed by miR-134 inhibitor transfection. DADS exhibited in vivo antitumor activity and upregulated miR-134 expression in xenograft tumors. Downregulation of miR-134 attenuated DADS-induced antitumor capacity. Further bioinformatics prediction analysis revealed that the 3'-untranslated region (3'-UTR) of Forkhead Box M1 (FOXM1) harbored miR-134-binding sites, and overexpression of miR-134 repressed the luciferase activity of the reporting vector containing FOXM1 3'-UTR. Both miR-134 overexpression and DADS inhibited FOXM1 expression in U2OS cells, while enforced expression of FOXM1 suppressed DADS-induced antiproliferation and anti-invasion capacity in U2OS cells. Furthermore, DADS treatment led to significant downregulation of cyclin D1, c-myc, and lymphoid enhancer-binding factor 1 expression, but the remarkably upregulated p21 level in U2OS cells. Collectively, DADS could be a promising anticancer agent for OS, and the underlying mechanisms might be associated with the antiproliferation and anti-invasion properties through upregulating miR-134 expression.

Comprehensive Investigation of miRNome Identifies Novel Candidate miRNA-mRNA Interactions Implicated in T-Cell Acute Lymphoblastic Leukemia

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy originating from T-cell precursors. The genetic landscape of T-ALL has been largely characterized by next-generation sequencing. Yet, the transcriptome of miRNAs (miRNome) of T-ALL has been less extensively studied. Using small RNA sequencing, we characterized the miRNome of 34 pediatric T-ALL samples, including the expression of isomiRs and the identification of candidate novel miRNAs (not previously annotated in miRBase). For the first time, we show that immunophenotypic subtypes of T-ALL present different miRNA expression profiles. To extend miRNome characteristics in T-ALL (to 82 T-ALL cases), we combined our small RNA-seq results with data available in Gene Expression Omnibus. We report on miRNAs most abundantly expressed in pediatric T-ALL and miRNAs differentially expressed in T-ALL versus normal mature T-lymphocytes and thymocytes, representing candidate oncogenic and tumor suppressor miRNAs. Using eight target prediction algorithms and pathway enrichment analysis, we identified differentially expressed miRNAs and their predicted targets implicated in processes (defined in Gene Ontology and Kyoto Encyclopedia of Genes and Genomes) of potential importance in pathogenesis of T-ALL, including interleukin-6-mediated signaling, mTOR signaling, and regulation of apoptosis. We finally focused on hsa-mir-106a-363 cluster and functionally validated direct interactions of hsa-miR-20b-5p and hsa-miR-363-3p with 3' untranslated regions of their predicted targets (PTEN, SOS1, LATS2), overrepresented in regulation of apoptosis. hsa-mir-106a-363 is a paralogue of prototypic oncogenic hsa-mir-17-92 cluster with yet unestablished role in the pathogenesis of T-ALL. Our study provides a firm basis and data resource for functional analyses on the role of miRNA-mRNA interactions in T-ALL.

WNK pathways in cancer signaling networks

Background

The with no lysine [K] (WNK) pathway consists of the structurally unique WNK kinases, their downstream target kinases, oxidative stress responsive (OSR)1 and SPS/Ste20-related proline-alanine-rich kinase (SPAK), and a multitude of OSR1/SPAK substrates including cation chloride cotransporters.

Main body

While the best known functions of the WNK pathway is regulation of ion transport across cell membranes, WNK pathway components have been implicated in numerous human diseases. The goal of our review is to draw attention to how this pathway and its components exert influence on the progression of cancer, specifically by detailing WNK signaling intersections with major cell communication networks and processes.

Conclusion

Here we describe how WNKs and associated proteins interact with and influence PI3K-AKT, TGF-β, and NF-κB signaling, as well as its unanticipated role in the regulation of angiogenesis.