STYK1 promotes Warburg effect through PI3K/AKT signaling and predicts a poor prognosis in nasopharyngeal carcinoma

Circular RNA COL1A1 promotes Warburg effect and tumor growth in nasopharyngeal carcinoma

OBJECTIVE

Circular RNAs (circRNAs), pivotal in the pathogenesis and progression of nasopharyngeal carcinoma (NPC), remain a significant point of investigation for potential therapeutic interventions. Our research was driven by the objective to decipher the roles and underlying mechanisms of hsa_circ_0044569 (circCOL1A1) in governing the malignant phenotypes and the Warburg effect in NPC.

METHODS

We systematically collected samples from NPC tissues and normal nasopharyngeal epithelial counterparts. The expression levels of circCOL1A1, microRNA-370-5p (miR-370-5p), and prothymosin alpha (PTMA) were quantitatively determined using quantitative polymerase chain reaction (qPCR) and Western blotting. Transfections in NPC cell lines were conducted using small interfering RNAs (siRNAs) or vectors carrying the pcDNA 3.1 construct for overexpression studies. We interrogated the circCOL1A1/miR-370-5p/PTMA axis's role in cellular functions through a series of assays: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide for cell viability, colony formation for growth, Transwell assays for migration and invasion, and Western blotting for protein expression profiling. To elucidate the molecular interactions, we employed luciferase reporter assays and RNA immunoprecipitation techniques.

RESULTS

Our investigations revealed that circCOL1A1 was a stable circRNA, highly expressed in both NPC tissues and derived cell lines. A correlation analysis with clinical pathological features demonstrated a significant association between circCOL1A1 expression, lymph node metastasis, and the tumor node metastasis staging system of NPC. Functionally, silencing circCOL1A1 led to substantial suppression of cell proliferation, migration, invasion, and metabolic alterations characteristic of the Warburg effect in NPC cells. At the molecular level, circCOL1A1 appeared to modulate PTMA expression by acting as a competitive endogenous RNA or 'sponge' for miR-370-5p, which in turn promoted the malignant characteristics of NPC cells.

CONCLUSION

To conclude, our findings delineate that circCOL1A1 exerts its oncogenic influence in NPC through the modulation of the miR-370-5p/PTMA signaling axis.

Influences of S100A8 and S100A9 on Proliferation of Nasopharyngeal Carcinoma Cells through PI3K/Akt Signaling Pathway

Objective

To investigate the effects of S100A8 and S100A9 on proliferation in nasopharyngeal carcinoma cells and the regulatory effects of PI3K/Akt signaling pathway.

Methods

Nasopharyngeal carcinoma cells (CNE1) were cultured and randomly divided into three groups: control group, S100A8/S100A9 overexpression group, and siRNA S100A8/S100A9 group. CCK-8 method was used to detect the effect of S100A8 and S100A9 on the viability of nasopharyngeal carcinoma cells. The effects of S100A8 and S100A9 on the colony forming ability of nasopharyngeal carcinoma cells were detected by colony forming assay. The effects of S100A8 and S100A9 on the proliferation of nasopharyngeal carcinoma cells were detected by EdU staining. The mRNA levels of PI3K and Akt were detected by RT-PCR. The expression levels of PI3K and Akt in NPC cells were detected by Western blot. Wortmannin, an inhibitor of PI3K/Akt pathway, was used to inhibit the activation of PI3K/Akt pathway.

Results

Compared with the control group, the cell viability, the number of plate clones, the positive rate of EdU staining, and the mRNA and protein levels of PI3K and Akt were increased in the overexpression group. Compared with the control group, the cell viability, the number of plate clones, the positive rate of EdU staining, and the mRNA and protein levels of PI3K and Akt were decreased in the siRNA group. After inhibiting the activation of PI3K/Akt pathway, the viability of NPC cells in the overexpression group decreased significantly at 48 h and 72 h, while that in the siRNA group increased significantly.

Conclusion

SiRNA S100A8 and S100A9 could inhibit the proliferation of nasopharyngeal carcinoma cells, and the underlying mechanism may be related to the inhibition of PI3K/Akt signaling pathway.

STYK1/NOK Promotes Metastasis and Epithelial-Mesenchymal Transition in Non-small Cell Lung Cancer by Suppressing FoxO1 Signaling

Aims

Serine/threonine/tyrosine kinase 1 (STYK1) has been previously shown to have oncogenic properties, and emerging evidence suggests that STYK1 expression correlates with epithelial-mesenchymal transition (EMT). However, the mechanism of STYK1 involvement in oncogenesis remains unknown. The present study aimed to elucidate how STYK1 expression level relates to the metastasis, migration, invasion, and EMT in non-small cell lung cancer (NSCLC) and to determine the molecular mechanism of STYK1 effects.

Methods

Serine/threonine/tyrosine kinase 1 (STYK1) expression level and its relationship with the prognosis of NSCLC were determined using the ONCOMINE database and clinical cases. Non-small cell lung cancer cell lines with the overexpression or knockdown of STYK1 were established to determine whether STYK1 promotes cell migration, invasion, and EMT in vitro and in vivo. In addition, a constitutively active FoxO1 mutant (FoxO1AAA) was used to examine the role of FoxO1 in the STYK1-mediated upregulation of metastasis and EMT in NSCLC.

Results

Serine/threonine/tyrosine kinase 1 (STYK1) was upregulated in NSCLC tissues and cell lines, and its overexpression correlated with poor prognosis in patients with NSCLC after surgery. Enhanced expression of STYK1 potentiated the migration, invasion, and EMT in SW900 cells, thereby promoting metastasis, whereas knockdown of STYK1 inhibited these cellular phenomena in Calu-1 cells. Furthermore, STYK1 expression was positively related to the level of phosphorylated-FoxO1, whereas the constitutively active FoxO1 mutant protected against the positive effect of STYK1 overexpression on cell migration, invasion, and EMT.

Conclusion

Serine/threonine/tyrosine kinase 1 (STYK1) was upregulated in NSCLC and correlated with poor clinical outcomes. In addition, STYK1 suppressed FoxO1 functions, thereby promoting metastasis and EMT in NSCLC.

Shikonin inhibits growth, invasion and glycolysis of nasopharyngeal carcinoma cells through inactivating the phosphatidylinositol 3 kinase/AKT signal pathway

Nasopharyngeal carcinoma (NPC) is a malignant tumor which is commonly found in East Asia and Africa. The present clinical treatment of NPC is still mainly based on chemotherapeutics and is prone to drug resistance and adverse reactions. Shikonin has been demonstrated to play the antitumor effect in various cancers. However, the specific effects and related regulatory mechanism of Shikonin in NPC have not been clearly declared yet. Cell viability was valued through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and cell proliferation was detected through colony formation assay and Bromodeoxyuridine (BrdU) assay. Hochest 33258 staining was used to value cell apoptosis. Cell migration and invasion were valued through wound healing and transwell invasion assay, respectively. Glucose uptake, lactate release, ATP level and pyruvate kinase M2 isoform (PKM2) activity were measured using corresponding assay kits. Western blotting was used to examine the expression of proteins related to cell proliferation, cell apoptosis, cell migration and the phosphatidylinositol 3 kinase (PI3K)/AKT signal pathway. We found that Shikonin treatment effectively suppressed cell proliferation and induced obvious cell apoptosis compared with the control. Besides, Shikonin treatment suppressed cell migration and invasion effectively. The detection about glycolysis showed that Shikonin treatment suppressed cell glucose uptake, lactate release and ATP level. The activity of PKM2 was also largely inhibited by Shikonin. Further study revealed that the PI3K/AKT signal pathway was inactivated by Shikonin treatment. In addition, the inducer of the PI3K/AKT signal pathway largely abolished the antitumor effect of Shikonin on cell proliferation, cell apoptosis, cell mobility and aerobic glycolysis in NPC cells. Shikonin inhibits growth and invasion of NPC cells through inactivating the PI3K/AKT signal pathway.

Downregulation of PER2 Promotes Tumor Progression by Enhancing Glycolysis via the Phosphatidylinositol 3-Kinase/Protein Kinase B Pathway in Oral Squamous Cell Carcinoma

PURPOSE

PER2 gene expression is downregulated in oral squamous cell carcinoma (OSCC) and may have a pivotal role in tumor suppression. However, the biological function and mechanism of action of PER2 in OSCC remain unclear. In this study, the biological functions and anticancer mechanisms of PER2 in OSCC were investigated.

MATERIALS AND METHODS

Both stably overexpressed and silenced PER2 OSCC cells were established as an experimental group; empty vector lentivirus and scramble short hairpin RNA lentivirus transfected-cells, as negative control groups; and untreated OSCC cells, as a blank group. Cell proliferation, apoptosis, and glycolysis potential assays were conducted. In addition, the expression of phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), phosphorylation of protein kinase B, hexokinase 2 (HK2), pyruvate kinase M (PKM2), and lactate dehydrogenase A (LDHA) was quantified by real-time quantitative polymerase chain reaction and Western blotting. Rescue experiments were performed by the addition of AKT activators in the overexpressed cell line and by the addition of glycolysis inhibitor in the silenced cell line. These findings were verified in vivo using stably transfected OSCC cells overexpressing PER2 implanted in nude mice.

RESULTS

PER2 overexpression significantly inhibited OSCC cell proliferation and glycolysis, promoted cell apoptosis, and reduced the expression of PI3K, phosphorylation of protein kinase B, HK2, PKM2, and LDHA. The converse was observed in PER2-silenced OSCC cells. After the addition of AKT activator to cultures of PER2-overexpressed OSCC cells, reduced glucose uptake, lactic acid production, and cell proliferation, combined with increased apoptosis, were substantially reversed. In addition, after the addition of HK2 inhibitor to PER2-silenced OSCC cells to inhibit glycolysis, the reduction in apoptosis and increased proliferation were significantly countermanded. Tumorigenesis experiments in vivo also confirmed that PER2 overexpression suppressed OSCC growth and decreased the expression of HK2, PKM2, and LDHA.

CONCLUSIONS

PER2 heightened glycolysis via the PI3K/AKT pathway, heightened cell proliferation and inhibited apoptosis via glycolysis, thereby promoting the development of OSCC.

[Recombinant methioninase regulates PI3K/Akt/Glut-1 pathway and inhibits aerobic glycolysis to promote apoptosis of gastric cancer cells]

OBJECTIVE

To investigate the molecular mechanism of recombinant methioninase (rMETase) in promoting apoptosis of gastric cancer cells.

METHODS

Gastric cancer SGC-7901 cells were treated with rMETase (final concentration of 1.25 and 2.50 mmmol/L) for 72 h, and the changes in the cell viability were detected using CCK-8 method and the cell morphology changes were observed under an inverted microscope. Plate colony formation assay was used to evaluate colony formation ability of the cells, and flow cytometry was performed to analyze the changes in cell apoptosis and cell cycles. Glucose and lactate levels in the culture medium were determined using a colorimetric method and ATP concentration was detected using a fluorescence microplate reader; Western blotting was used to assess the effect of rMETase on PI3K/Akt pathway, glucose transporter-1 (GLUT-1), glycolysis- related proteins and apoptotic proteins in SGC-7901 cells.

RESULTS

rMETase significantly inhibited the proliferation and clonal formation, promoted cell apoptosis, and induced cell cycle arrest in S phase in SGC-7901 cells (P < 0.05). With the increase of rMETase concentration, the cells showed obviously decreased glucose intake accompanied by decreased glycolysis and ATP concentration (P < 0.001). The results of Western blotting showed that the expressions of PI3K, p-Akt/t-Akt, GLUT-1, and the key glycolytic enzymes HK2, PFKM, LDHA, antiapoptosis protein Bcl-2 were all downregulated and the pro-apoptotic proteins Bax and caspase-3 were up-regulated in response to rMETase treatment in SGC-7901 cells (P < 0.01).

CONCLUSIONS

rMETase can inhibit aerobic glycolysis, induce apoptosis and inhibit the proliferation of SGC-7901 cells by inhibiting the activity of PI3K/Akt/GLUT-1 pathway, suggesting its potential as a therapeutic agent for gastric cancer.

INHBA is a prognostic predictor for patients with colon adenocarcinoma

BACKGROUND

Colon adenocarcinoma (COAD) is one of the most lethal cancers. It is particularly important to accurately predict prognosis and to provide individualized treatment. Several lines of evidence suggest that genetic factors and clinicopathological characteristics are related to cancer onset and progression. The aim of this study was to identify potential prognostic genes and to develop a nomogram to predict survival and recurrence of COAD.

METHODS

To identify potential prognostic genes in COAD, microarray datasets were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were obtained from GEO2R. Venn diagram was drawn to select those genes that were overexpressed in all datasets, and survival analyses were performed to determine the prognostic values of the selected genes. New nomograms were developed based on the genes that were significantly associated with prognosis. Clinicopathological data were obtained from The Cancer Genome Atlas (TCGA). Finally, the new nomograms were compared head-to-head comparison with the TNM nomogram.

RESULTS

From GSE21510, GSE110223, GSE113513 and GSE110224, a total of 834, 218, 236 and 613 overexpressed DEGs were screened out, respectively. The Venn diagram revealed that 12 genes appeared in all four profiles. After survival analyses, only INHBA expression was associated with both overall survival (OS) and disease-free survival (DFS). Multivariate analyses revealed that age, pathological N and pathological M were significant independent risk factors for OS. Age, pathological N, pathological M and INHBA were significant independent risk factors for DFS. Two prediction models predicted the probability of 3-year survival and 5-year survival for OS and DFS, respectively. The concordance indexes were 0.785 for 3-year overall survival, 0.759 for 5-year overall survival, 0.789 for 3-year disease-free survival and 0.757 for 5-year disease-free survival. The head-to-head comparison according to time-dependent ROC curves indicated that the new models had higher predictive accuracy. Decision curve analyses (DCA) indicated that the clinical value of the new models were higher than TNM models for predicting disease-free survival.

CONCLUSION

The combination of INHBA expression with a clinical nomogram improves prognostic power in colon adenocarcinoma, especially for predicting recurrence.

Suppressed "Warburg Effect" in Nasopharyngeal Carcinoma Via the Inhibition of Pyruvate Kinase Type M2-Mediated Energy Generation Pathway

Warburg effect describes the abnormal energy metabolism in cancer cells and pyruvate kinase type M2 is involved in the regulation of this effect. In the current study, the role of pyruvate kinase type M2 in the initiation of Warburg effect in nasopharyngeal carcinoma cells was explored. The expression status of pyruvate kinase type M2 was detected in nasopharyngeal carcinoma samples and analyzed by different clinicopathological characteristics. Then the level of pyruvate kinase type M2 was suppressed in 2 nasopharyngeal carcinoma cell lines. The effects of pyruvate kinase type M2 inhibition on cell viability, apoptosis, invasion, glucose uptake, ATP generation, and glycolysis metabolism were determined. The data showed that the high expression of pyruvate kinase type M2 in nasopharyngeal carcinoma tissues was associated with the larger tumor size and advanced metastasis in the patients. The inhibition of pyruvate kinase type M2 resulted in the repressed proliferation and invasion in nasopharyngeal carcinoma cells, along with the increased apoptotic rate. The lack of pyruvate kinase type M2 function inhibited glucose uptake, while increased ATP generation in nasopharyngeal carcinoma cells. Moreover, the production of glycolysis metabolites, including pyruvic acid, lactate, citrate, and malate, was also suppressed by pyruvate kinase type M2 inhibition. At molecular level, the expressions of glucose transporter and hexokinase 2 were downregulated by pyruvate kinase type M2 inhibition, confirming the changes in glucose metabolism. Collectively, the current study demonstrated that the function of pyruvate kinase type M2 was important to maintain the proliferation and invasion of nasopharyngeal carcinoma cells, and the inhibition of the factor would antagonize nasopharyngeal carcinoma by blocking Warburg effect.

Styk1 expression is a hallmark of murine NK cells and other NK1.1+ subsets but is dispensable for NK-cell development and effector functions

To gain insight into the biology of NK cells, others and we previously identified the NK-cell signature, defined as the set of transcripts which expression is highly enriched in these cells compared to other immune subtypes. The transcript encoding the Serine/threonine/tyrosine kinase 1 (Styk1) is part of this signature. However, the role of Styk1 in the immune system is unknown. Here, we report the generation of a novel transgenic mouse model, in which Styk1 expression is invalidated and replaced by an EGFP reporter cassette. We demonstrated that Styk1 expression is a hallmark of NK cells and other NK1.1 expressing cells such as liver type 1 innate lymphoid cells (ILC1) and NK1.1⁺ γδ T cells. Styk1 expression is maintained by IL-15 in NK cells and negatively correlates with the expression of educating NK-cell receptors. Analysis of phosphorylation levels of mTOR substrates suggested that Styk1 could moderately contribute to the activity of the PI3K/Akt/mTOR pathway. However, Styk1-deficient NK cells develop normally and have normal in vitro and in vivo effector functions. Thus Styk1 expression is a hallmark of NK cells, ILC1 and NK1.1⁺ T cells but is dispensable for their development and immune functions.

Low STYK1 expression indicates poor prognosis in gastric cancer

Background

The expression of serine threonine tyrosine kinase 1 (STYK1), a member of the receptor protein tyrosine kinase (RPTK) family, is abnormal in several cancers. However, the molecular mechanism of STYK1 regulation of gastric cancer (GC) progression is unknown.

Materials and methods

We evaluated STYK1 expression in GC tissues and the corresponding normal tissues. Specimens from 93 patients with GC were examined with immunohistochemical staining. The relationship between STYK1 protein expression and the patients' clinicopathological features was assessed. Kaplan-Meier and Cox proportional regression analyses were used to evaluate the association between STYK1 expression and survival.

Results

STYK1 expression was decreased in GC tissues. Low STYK1 expression was significantly associated with poor tumor differentiation (P=0.023), advanced clinical stage (P=0.021), and poor overall survival (OS; P=0.034). Univariate and multivariate analyses revealed that STYK1expression was an independent prognostic indicator (HR =0.53, 95% CI =0.29-0.95, P=0.039; HR =0.51, 95% CI =0.24-0.91, P=0.030, respectively).

Conclusion

Downregulated STYK1 expression correlated significantly with poor tumor differentiation, advanced clinical stage, and poor OS in GC. STYK1 might be a diagnostic and prognostic indicator in patients with GC.

Cryptic sequence features in the active postmortem transcriptome

BACKGROUND

Our previous study found that more than 500 transcripts significantly increased in abundance in the zebrafish and mouse several hours to days postmortem relative to live controls. The current literature suggests that most mRNAs are post-transcriptionally regulated in stressful conditions. We rationalized that the postmortem transcripts must contain sequence features (3- to 9- mers) that are unique from those in the rest of the transcriptome and that these features putatively serve as binding sites for proteins and/or non-coding RNAs involved in post-transcriptional regulation.

RESULTS

We identified 5117 and 2245 over-represented sequence features in the mouse and zebrafish, respectively, which represents less than 1.5% of all possible features. Some of these features were disproportionately distributed along the transcripts with high densities in the 3' untranslated regions of the zebrafish (0.3 mers/nt) and the open reading frames of the mouse (0.6 mers/nt). Yet, the highest density (2.3 mers/nt) occurred in the open reading frames of 11 mouse transcripts that lacked 3' or 5' untranslated regions. These results suggest the transcripts with high density of features might serve as 'molecular sponges' that sequester RNA binding proteins and/or microRNAs, and thus indirectly increase the stability and gene expression of other transcripts. In addition, some of the features were identified as binding sites for Rbfox and Hud proteins that are also involved in increasing transcript stability and gene expression.

CONCLUSIONS

Our results are consistent with the hypothesis that transcripts involved in responding to extreme stress, such as organismal death, have sequence features that make them different from the rest of the transcriptome. Some of these features serve as putative binding sites for proteins and non-coding RNAs that determine transcript stability and fate. A small number of the transcripts have high density sequence features, which are presumably involved in sequestering RNA binding proteins and microRNAs and thus preventing regulatory interactions among other transcripts. Our results provide baseline data on post-transcriptional regulation in stressful conditions that has implications for regulation in disease, starvation, and cancer.

SUMOylation Regulates Transcription by the Progesterone Receptor A Isoform in a Target Gene Selective Manner

Luminal breast cancers express estrogen (ER) and progesterone (PR) receptors, and respond to endocrine therapies. However, some ER+PR+ tumors display intrinsic or acquired resistance, possibly related to PR. Two PR isoforms, PR-A and PR-B, regulate distinct gene subsets that may differentially influence tumor fate. A high PR-A:PR-B ratio is associated with poor prognosis and tamoxifen resistance. We speculate that excessive PR-A marks tumors that will relapse early. Here we address mechanisms by which PR-A regulate transcription, focusing on SUMOylation. We use receptor mutants and synthetic promoter/reporters to show that SUMOylation deficiency or the deSUMOylase SENP1 enhance transcription by PR-A, independent of the receptors’ dimerization interface or DNA binding domain. De-SUMOylation exposes the agonist properties of the antiprogestin RU486. Thus, on synthetic promoters, SUMOylation functions as an independent brake on transcription by PR-A. What about PR-A SUMOylation of endogenous human breast cancer genes? To study these, we used gene expression profiling. Surprisingly, PR-A SUMOylation influences progestin target genes differentially, with some upregulated, others down-regulated, and others unaffected. Hormone-independent gene regulation is also PR-A SUMOylation dependent. Several SUMOylated genes were analyzed in clinical breast cancer database. In sum, we show that SUMOylation does not simply repress PR-A. Rather it regulates PR-A activity in a target selective manner including genes associated with poor prognosis, shortened survival, and metastasis.

Aberrant expression of STYK1 and E-cadherin confer a poor prognosis for pancreatic cancer patients

Previous studies showed that aberrant Serine/threonine/tyrosine kinase 1 (STYK1, also known as NOK) or/and E-cadherin were involved in the progression of some types of human cancers. However, whether they contributed to the development of pancreatic cancer was unknown. Here, we investigated the prognostic significance of aberrant STYK1 and E-cadherin in pancreatic cancer. Our results showed that STYK1 expression increased while E-cadherin decreased in pancreatic cancer tissues compared with normal pancreas tissues. STYK1 level was positively correlated with lymph node metastasis and clinical stage in pancreatic cancer patients. E-cadherin expression was inversely correlated with STYK1 expression in pancreatic cancer tissue samples. Patients with high STYK1 and low E-cadherin expression had the worst prognosis. In addition, STYK1 knockdown in pancreatic cancer cell lines inhibited cell proliferation, enhanced cell apoptosis, induced cell cycle arrest, and prohibited cell migration, while STYK1 over-expression showed the opposite effects. Silencing STYK1 also increased E-cadherin expression and inhibited epithelial-to-mesenchymal transition (EMT) and p-p38 expression in vitro. Over-expression had showed the opposite trends, and treatment with p38 inhibitor, SB203580, could reverse the trends. Thus, STYK1 repressed E-cadherin expression and promoted EMT, mediated by p38 MAPK signaling pathway, which was the possible mechanism for STYK1-mediated pancreatic cancer cell proliferation and migration. In summary, our results showed that STYK1 might be a prognostic marker for pancreatic cancer patients and might be a novel strategy for the treatment of pancreatic cancer.