FOXO1 down-regulation is associated with worse outcome in bladder cancer and adds significant prognostic information to p53 overexpression

New sights on long non-coding RNAs in glioblastoma: A review of molecular mechanism

Glioma or glioblastoma (GBM) is one of the aggressive and fatal primary cerebral malignancies, with the highest mortality rate among all brain-related tumors. Also, glioma mainly progresses as a more invasive phenotype after primary treatment. Cumulative evidence suggested that dysregulation of noncoding RNAs (ncRNAs) such as long non-coding RNAs (LncRNAs) and microRNAs (miRNAs) are associated with tumor initiation, progression, and drug resistance, through epigenetic modifications, transcriptional, and post-transcriptional processes in the cells. Many scientific investigations have revealed that LncRNAs play important roles in various biological procedures linked with the development and progression of GBM. In recent years, it has been shown that dysregulation of molecular mechanisms in many LncRNAs such as MIR22HG, HULC, AGAP2-AS1, MALAT1, PVT1, TTTY14, HOTAIRM1, PTAR, LPP-AS2, LINC00336, and TINCR are connected with the GBM. Therefore, this scientific review paper focused on the molecular mechanisms of these LncRNAs in the context of GBM.

A serum miRNAs signature for early diagnosis of bladder cancer

BACKGROUND

Bladder cancer accounts for the most common type of urologic malignancy and presents high recurrence rate after surgical resection and adjuvant intravesical therapy. We aim to search for an early diagnostic biomarker in serum for bladder cancer in this study.

METHODS

The expression profiles of miRNAs in serum samples of 112 bladder cancer patients and 112 healthy controls were detected with real-time polymerase chain reaction (RT-qPCR). Receiver operating characteristic (ROC) curve and area under curve (AUC) analysis were performed to assess the diagnostic efficiency of miRNAs. Stepwise logic regression analysis was used to construct a diagnostic signature with highest sensitivity and specificity. Bioinformatics analysis was applied to explore the potential biological functions and mechanisms of candidate miRNAs.

RESULTS

Five miRNAs including miR-451a, miR-381-3p, miR-223-3p, miR-142-5p and miR-27b-3p were found differentially expressed in serum samples of bladder patients and healthy subjects. The diagnostic signature was constructed with miR-27b-3p, miR-381-3p and miR-451a. AUC of the three-miRNA signature was 0.894 (0.837-0.936, p < 0.001). The sensitivity and specificity of this signature were 86.90% and 77.38%, respectively, indicating that this signature has a good ability to diagnose bladder cancer.

CONCLUSION

The three-miRNA signature we constructed has favorable diagnostic capacity and may be a promising non-invasive biomarker in the early diagnosis of bladder cancer.KEY MESSAGESThere is still no clinical utilization of serum miRNAs in the early detection of bladder cancer.We screened and constructed a three-miRNA signature with the sensitivity of 86.90% and specificity of 77.38% which may be a promising non-invasive biomarker in the early diagnosis of bladder cancer.

HYOU1 promotes cell proliferation, migration, and invasion via the PI3K/AKT/FOXO1 feedback loop in bladder cancer

BACKGROUND

Hypoxia up-regulated 1 (HYOU1) was identified as a proto-oncogene and involved in tumorigenesis and progression in several cancer. Nonetheless, the biological function and mechanism of HYOU1 in bladder cancer (BCa) remian unclear.

METHODS

The HYOU1 level in BCa tissues and cells was examined using RT-qPCR and western blot methods. The relationship between HYOU1 expression and clinicopathologic characteristics of BCa was analyzed. The biological role of HYOU1 on BCa cell proliferation, apoptosis, migration and invasion were analyzed via counting kit-8 (CCK-8), flow cytometry, wound healing and Transwell assays, respectively. The association between HYOU1 and the PI3K/AKT/Forkhead box O1 (FOXO1) signalling was assessed via western blot assay, meanwhile the the association of FOXO1 with HYOU1 was also investigated.

RESULTS

HYOU1 was up-regulated in BCa tissues and cell lines, and the high level of HYOU1 was associated with bladder cancer histological grade and pathologic stage. Moreover, patients with high expression of HYOU1 showed poor overall survival from Kaplan-Meier Plotter. HYOU1 depletion impeded cell proliferation, migration and invasion, and induced cell apoptosis, while HYOU1 overexpression promoted cell proliferation, migration and invasion. Mechanically, our results showed that HYOU1 knockdown repressed PI3K/AKT/FOXO1 pathway and HYOU1 was negative regulated by FOXO1 in BCa. Significantly, we confirmed that the HYOU1/PI3K-AKT/FOXO1 negative feedback loop was involved in BCa cell proliferation, migration and invasion.

CONCLUSION

These findings revealed that HYOU1 acted as a pro-oncogene on BCa progression, and it will be a possible target for BCa treatment.

Alterations of Chromatin Regulators in the Pathogenesis of Urinary Bladder Urothelial Carcinoma

Simple Summary

Urinary bladder cancer is one of the ten major cancers worldwide, with higher incidences in males, in smokers, and in highly industrialized countries. New therapies beyond cytotoxic chemotherapy are urgently needed to improve treatment of these tumors. A better understanding of the mechanisms underlying their development may help in this regard. Recently, it was discovered that a group of proteins regulating the state of chromatin and thus gene expression is exceptionally and frequently affected by gene mutations in bladder cancers. Altered function of these mutated chromatin regulators must therefore be fundamental in their development, but how and why is poorly understood. Here we review the current knowledge on changes in chromatin regulators and discuss their possible consequences for bladder cancer development and options for new therapies.

Abstract

Urothelial carcinoma (UC) is the most frequent histological type of cancer in the urinary bladder. Genomic changes in UC activate MAPK and PI3K/AKT signal transduction pathways, which increase cell proliferation and survival, interfere with cell cycle and checkpoint control, and prevent senescence. A more recently discovered additional category of genetic changes in UC affects chromatin regulators, including histone-modifying enzymes (KMT2C, KMT2D, KDM6A, EZH2), transcription cofactors (CREBBP, EP300), and components of the chromatin remodeling complex SWI/SNF (ARID1A, SMARCA4). It is not yet well understood how these changes contribute to the development and progression of UC. Therefore, we review here the emerging knowledge on genomic and gene expression alterations of chromatin regulators and their consequences for cell differentiation, cellular plasticity, and clonal expansion during UC pathogenesis. Our analysis identifies additional relevant chromatin regulators and suggests a model for urothelial carcinogenesis as a basis for further mechanistic studies and targeted therapy development.

Forkhead box O1 targeting replication factor C subunit 2 expression promotes glioma temozolomide resistance and survival

Background

Additional mechanisms of temozolomide (TMZ) resistance in gliomas remain uncertain. The aim of this study was to identify another DNA repair mechanism involving forkhead box O1 (FoxO1) and replicator C2 (RFC2) in gliomas.

Methods

We established glioma cells against TMZ, U87R, by exposure to TMZ. Proliferation rate Cell counting kit-8 (CCK8) was used, and epithelial-mesenchymal transition (EMT)-related markers were detected by western blot. The association between FoxO1 and RFC2 was analyzed by heat maps and scatter plot, and Real-time reverse transcription polymerase chain reaction (qRT-PCR) and Western blot were used to detect the effect of FoxO1 on the expression of RFC2. The regulation effect of FoxO1 on RFC2 expression was analyzed by luciferase reporter gene assay. Knockdown of FoxO1/RFC2 was achieved via short hairpin RNA (shRNA), the effect of knockdown on the proliferation was determined by CCK8 assay and colony formation assay, and apoptosis was examined by flow cytometry and immunoblotting.

Results

The TMZ-resistant glioma cell line, U87R, was established. The FoxO1 and RFC2 proteins increased significantly in U87R. The expression of FoxO1 and RFC2 were positively related in glioma tissues. We found that FoxO1 contributes to TMZ resistance and cell survival via regulating the expression of RFC2. Moreover, FoxO1 functions as a transcriptional activator to RFC2 by binding to the promoter of RFC2. Furthermore, knockdown of FoxO1/RFC2 suppressed cell proliferation, TMZ resistance, and induced apoptosis in U87R.

Conclusions

The FoxO1/RFC2 signaling pathway promotes glioma cell proliferation and TMZ resistance, suggesting that the FoxO1/RFC2 pathway may be a potential target for TMZ-resistant glioma therapy.

HnRNP-F promotes the proliferation of bladder cancer cells mediated by PI3K/AKT/FOXO1

Our previous study showed that heterogeneous nuclear ribonucleoprotein F (hnRNP-F) could induce epithelial-mesenchymal transition and metastasis in bladder cancer (BC), however, the role and mechanism of hnRNP-F in mediating the proliferative ability of BC cells remain unclear. HnRNP-F promoted the proliferation of BC cells by using BC cell lines and cell counting kit-8 (CCK8), colony formation and flow cytometry assays in vitro. Furthermore, the association of hnRNP-F with the phosphoinositide 3‑kinase (PI3K)/protein kinase B (AKT) signalling pathway was confirmed by western blotting after bioinformatic analysis. HnRNP-F expression was significantly decreased by treatment with the PI3K/AKT signalling pathway inhibitor LY294002, whereas hnRNP-F knockdown did not significantly affect PI3K or AKT expression, suggesting that hnRNP-F is likely a downstream target of the PI3K/AKT pathway. Forkhead box O1 (FOXO1) is a molecule downstream of PI3K/AKT and can be inhibited by phosphorylation. In addition, chromatin immunoprecipitation (ChIP) and luciferase reporter assays indicated that FOXO1 expression was negatively correlated with hnRNP-F expression as FOXO1 was found to bind to the promoter region of hnRNP-F mRNA and inhibit its transcription. To sum up, our findings suggest that hnRNP-F expression is regulated by the PI3K/AKT-mediated phosphorylation of FOXO1, with phosphorylation inhibiting FOXO1, which subsequently allows hnRNP-F to promote proliferation. This finding is a novel discovery in BC and could help reveal the mechanism of BC progression.

FOXO1 inactivation induces cisplatin resistance in bladder cancer

We found that FOXO1-shRNA sublines or FOXO1-positive cells co-treated with a FOXO1 inhibitor were significantly more resistant to cisplatin treatment at pharmacological concentrations, compared with respective control sublines or those with mock treatment. Western blot demonstrated considerable increases in the expression levels of a phosphorylated inactive form of FOXO1 (p-FOXO1) in cisplatin-resistant sublines established by long-term culture with low/increasing doses of cisplatin, compared with respective controls. Immunohistochemistry in surgical specimens from patients with muscle-invasive bladder cancer undergoing cisplatin-based neoadjuvant therapy further showed a strong trend to associate between p-FOXO1 positivity and unfavorable response to chemotherapy.

Bladder neoplasms and NF-κB: an unfathomed association

Introduction: Bladder cancer is the second most common genitourinary tract cancer and is often recurrent and/or chemoresistant after tumor resection. Cigarette smoking, exposure to aromatic amines, and chronic infection/inflammation are bladder cancer risk factors. NF-κB is a transcription factor that plays a critical role in normal physiology and bladder cancer. Bladder cancer patients have constitutively active NF-κB triggered by pro-inflammatory cytokines, chemokines, and hypoxia, augmenting carcinogenesis and progression.Areas covered: NF-κB orchestrates protein interactions (PTEN, survivin, VEGF), regulation (CYLD, USP13) and gene expression (Trp 53) resulting in bladder cancer progression, recurrence and resistance to therapy. This review focuses on NF-κB in bladder inflammation, cancer and resistance to therapy.Expert opinion: NF-κB and bladder cancer necessitate further research to develop better diagnostic and treatment regimens that address progression, recurrence and resistance to therapy. NF-κB is a master regulator that can act with or on minimally one cancer hallmark gene or protein, leading to bladder cancer progression (Tp53, PTEN, VEGF, HMGB1, CYLD, USP13), recurrence (PCNA, BcL-2, JUN) and resistance to therapy (P-gp, twist, SETD6). Thus, an understanding of bladder cancer in relation to NF-κB will offer improved strategies and efficacious targeted therapies resulting in minimal progression, recurrence and resistance to therapy.

MiR-142-3p functions as an oncogene in prostate cancer by targeting FOXO1

Prostate cancer (PCa) is a heterogeneous malignancy, and is a primary cause of cancer-related death in males. Forkhead box transcription factor O1 (FOXO1) exerts antitumor effects in various cancers, including PCa. However, the regulatory mechanism of miR-142-3p on FOXO1 expression in human PCa has not been characterized. In this study, we showed that FOXO1 protein levels were downregulated in PCa tissues and cells. Moreover, FOXO1 expression was a predictor of disease-free survival in patients with PCa and was a predictor of prognosis. Increased expression of FOXO1 suppressed cellular proliferation and induced cell cycle arrest at G0/G1 in vitro. However, FOXO1 mRNA and protein levels were inconsistent in human PCa tissues and cell lines. We showed that miR-142-3p levels were negatively correlated with FOXO1 protein levels in PCa. We also showed that miR-142-3p suppressed FOXO1 expression by directly targeting its 3′-untranslated region. Furthermore, suppression of miR-142-3p inhibited cell proliferation and induced cell cycle arrest, and these effects were blocked by FOXO1 knockdown. In vivo experiments showed that miR-142-3p knockout impaired tumor growth. Our results validate that FOXO1 acted as a tumor suppressor in PCa and demonstrated that FOXO1 was regulated by miR-142-3p, and miR-142-3p may be a potential target for treatment of PCa.

Urinary peptide panel for prognostic assessment of bladder cancer relapse

Non-invasive tools stratifying bladder cancer (BC) patients according to the risk of relapse are urgently needed to guide clinical intervention. As a follow-up to the previously published study on CE-MS-based urinary biomarkers for BC detection and recurrence monitoring, we expanded the investigation towards BC patients with longitudinal data. Profiling datasets of BC patients with follow-up information regarding the relapse status were investigated. The peptidomics dataset (n = 98) was split into training and test set. Cox regression was utilized for feature selection in the training set. Investigation of the entire training set at the single peptide level revealed 36 peptides being strong independent prognostic markers of disease relapse. Those features were further integrated into a Random Forest-based model evaluating the risk of relapse for BC patients. Performance of the model was assessed in the test cohort, showing high significance in BC relapse prognosis [HR = 5.76, p-value = 0.0001, c-index = 0.64]. Urinary peptide profiles integrated into a prognostic model allow for quantitative risk assessment of BC relapse highlighting the need for its incorporation in prospective studies to establish its value in the clinical management of BC.

Forkhead box O1 as an indicator of prognosis is inactivated in urothelial carcinoma of the upper urinary tract

The transcription factor forkhead box O1 (FOXO1) can be inactivated via its phosphorylation, resulting in suppression of apoptosis. Using immunohistochemistry, the expression of a phosphorylated form of FOXO1 was assessed in upper urinary tract urothelial carcinoma (UUTUC) specimens. Overall, phospho-FOXO1 (p-FOXO1) was immunoreactive in all 99 UUTUC specimens [12 (12.1%) weak (1+), 46 (46.5%) moderate (2+) and 41 (41.4%) strong (3+)], which was significantly (P=0.018) increased, compared with benign urothelium specimens [77/82 (93.9%): 18 (22.0%) 1+, 41 (50.0%) 2+ and 18 (22.0%) 3+]. Muscle invasion (P=0.031) and lymphovascular invasion (P=0.025) were observed more frequently in p-FOXO1(2+/3+) tumor samples compared with p-FOXO1(1+) tumor samples. No statistically significant associations between p-FOXO1 expression and tumor grade or presence of concurrent carcinoma in situ, hydronephrosis or lymph node metastasis were observed. Furthermore, the levels of p-FOXO1 and estrogen receptor-β expression were significantly (P<0.05) correlated in UUTUC samples [correlation coefficient (CC)=0.244], particularly in tumor samples from male patients (CC=0.330). Additionally, patients with p-FOXO1(3+) tumors had a significantly increased risk of cancer-specific mortality (P=0.043), compared with those with p-FOXO1(1+/2+) tumors. Multivariate analysis further demonstrated a notable, albeit not significant, association between p-FOXO1 expression and cancer-specific survival (hazard ratio=2.204; P=0.053). These findings indicate that FOXO1 is inactivated in UUTUC specimens and p-FOXO1 overexpression may serve as a predictor of poor patient outcomes.

Elucidating the gene regulatory networks modulating cancer stem cells and non-stem cancer cells in high grade serous ovarian cancer

The origin and pathogenesis of epithelial ovarian cancer have perplexed investigators for decades. The most prevalent type of it is the high-grade serous ovarian carcinoma (HGSOv) which is a highly aggressive disease with high relapse rates and insurgence of chemo-resistance at later stages of treatment. These are driven by a rare population of stem cell like cancer cells called cancer stem cells (CSCs). We have taken up a systems approach to find out the common gene interaction paths between non-CSC tumor cells (CCs) and CSCs in HGSOv. Detailed investigation reveals a set of 17 Transcription Factors (named as pivot-TFs) which can govern changes in the mode of gene regulation along these paths. Overall, this work highlights a divergent road map of functional information relayed by these common key players in the two cell states, which might aid towards designing novel therapeutic measures to target the CSCs for ovarian cancer therapy.

Higher expression of FOXOs correlates to better prognosis of bladder cancer

Background

We aimed to explore the expression of forkhead box class O (FOXO) and relations between expressions of FOXOs and clinicopathological characteristics and prognosis of bladder cancer.

Methods

We enrolled a cohort of 276 patients with bladder cancer in our study. Expressions of FOXOs in bladder cancer tissue and adjacent tissue were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC). Correlations between expression of FOXOs and clinicopathological characteristics and prognosis were analyzed. The relationship between expression of FOXOs and survival time of patients with bladder cancer was analyzed by the Kaplan-Meier survival analysis and the Log-rank test; individual variables which may affect the prognosis of bladder cancer were detected by the Cox proportional hazard regression model.

Results

Compared with bladder cancer tissue, a higher expression of FOXOs was detected in paracancerous tissue. We found significant associations between histological grade and the expressions of FOXOs, clinical stage and the expressions of FOXOs, and lymph node metastasis and the expressions of FOXOs (all P < 0.05). When used for diagnosing bladder cancer, the mRNA expression of FOXO1/3/4 produced cut off values of 1.475, 1.305, and 1.295, respectively, exhibiting relatively high specificity and sensitivity. The Kaplan-Meier curves indicated that patients with a higher expression of FOXOs tended to have a longer overall survival than those with lower expression. The Cox regression analysis revealed that lymph node metastasis, high clinical stage, and low expression of FOXOs were independent risk factors for bladder cancer prognosis.

Conclusion

Our results indicate that the expression of FOXOs is closely correlated with clinicopathological characteristics and prognosis of bladder cancer.

TPX2-p53-GLIPR1 regulatory circuitry in cell proliferation, invasion, and tumor growth of bladder cancer

The targeting protein for Xenopus kinesin-like protein 2 (TPX2) is associated with the metastasis and prognosis of bladder cancer. p53 is closely related to the progression of bladder cancer. Human glioma pathogenesis-related protein 1 (GLIPR1) is a p53 target gene with antitumor activity. This study aims to explore the interplay between TPX2, p53, and GLIPR1 and its correlation with cell proliferation, invasion, and tumor growth in bladder cancer. Here, Western blot and qRT-PCR analysis revealed that TPX2 at both mRNA and protein levels was up-regulated in bladder carcinoma tissues compared to their paired adjacent normal tissues. Additionally, tissues expressing high TPX2 level exhibited high p53 level and low GLIPR1 level. The expressions of TPX2 and p53 in non-muscle-invasive bladder cancer cells (KK47 and RT4) were lower than those in muscle-invasive bladder cancer cells (T24, 5637, and UM-UC-3), while GLIPR1 showed the converse expression pattern. Further investigation revealed that TPX2 activated the synthesis of p53; and GLIPR1 is up-regulated by wild-type (wt)-p53 but not affected by mutated p53; Additionally, GLIPR1 inhibited TPX2. These data suggested a TPX2-p53-GLIPR1 regulatory circuitry. Meanwhile, TPX2 overexpression promoted while overexpression of GLIPR1 or p53 inhibited bladder cancer growth. Interestingly, in T24 cells with mutated p53, p53 silence suppressed bladder cancer growth. This study identified a novel TPX2-p53-GLIPR1 regulatory circuitry which modulated cell proliferation, migration, invasion, and tumorigenicity of bladder cancer. Our findings provide new insight into underlying mechanisms of tumorigenesis and novel therapeutic options in bladder cancer.