Understanding the Role of Non-Coding RNAs in Bladder Cancer: From Dark Matter to Valuable Therapeutic Targets

The crosstalk between metabolic reprogramming and epithelial-mesenchymal transition and their synergistic roles in distant metastasis in breast cancer

BACKGROUND

Metabolic reprogramming (MR) and epithelial-mesenchymal transition (EMT) are crucial phenomena involved in the distant metastasis of breast cancer (BRCA). This study aims to assess the risk of distant metastasis in BRCA patients based on MR and EMT processes and investigate their underlying mechanisms.

METHODS

Gene sets related to EMT and MR were downloaded. MR-related genes (MRG) and EMT-related genes (ERG) were obtained. Principal Component Analysis method was used to define the EMT Potential Index (EPI) and MR Potential Index (MPI) to quantify the EMT and MR levels in each tumor tissue. A linear scoring model, the Metastasis Score, was derived using the union of MRGs and ERGs to evaluate the risk of distant metastasis/recurrence in BRCA. The Metastasis Score was then validated in multiple datasets. Additionally, our study explored the underlying mechanism of the Metastasis Score and its association with tumor immunity, focusing on HPRT1 gene expression in breast cancer tissues of transfer and untransferred groups using experimental methods.

RESULTS

A total of 59 MRGs and 30 ERGs were identified in the present study. Stratifying the dataset based on EPI and MPI revealed significantly lower survival rates (P < .05) in the MPI_high and EPI_high groups. Kaplan-Meier analysis indicated the lowest survival rate in the EPI-high + MPI-high group. The Metastasis Score demonstrated its ability to distinguish prognoses in GSE2034, GSE17705, and TCGA-BRCA datasets. Additionally, differences in mutated genes were found between the high- and the low-Metastasis Score groups, displaying significant associations with immune cell infiltration and anti-tumor immune status. Notably, the 13 genes included in the Metastasis Score showed a strong association with prognosis and tumor immunity. Immunohistochemistry and western blot results revealed high expression of the HPRT1 gene in the transfer group.

CONCLUSION

This study established the Metastasis Score as a reliable tool for evaluating the risk of distant metastasis/recurrence in BRCA patients. Additionally, we identified key genes involved in MR and EMT crosstalk, offering valuable insights into their roles in tumor immunity and other relevant aspects.

Comprehensive analysis of mitochondria-related genes indicates that PPP2R2B is a novel biomarker and promotes the progression of bladder cancer via Wnt signaling pathway

Bladder cancer (BC) is the fourth and tenth most common malignancy in men and women worldwide, respectively. The complexity of the molecular biological mechanism behind BC is a major contributor to the lack of effective treatment management of the disease. The development and genesis of BC are influenced by mitochondrial retrograde control and mitochondria-nuclear cross-talk. However, the role of mitochondrial-related genes in BC remains unclear. In this study, we analyzed TCGA datasets and identified 752 DE-MRGs in BC samples, including 313 down-regulated MRGs and 439 up-regulated MRGs. Then, the results of machine-learning screened four critical diagnostic genes, including GLRX2, NMT1, PPP2R2B and TRAF3IP3. Moreover, we analyzed their prognostic value and confirmed that only PPP2R2B was associated with clinical prognosis of BC patients and Cox regression assays validated that PPP2R2B expression was a distinct predictor of overall survival in BC patients. Them, we performed RT-PCR and found that PPP2R2B expression was distinctly decreased in BC specimens and cell lines. Functional experiments revealed that overexpression of PPP2R2B distinctly suppressed the proliferation, migration and invasion of BC cells via Wnt signaling pathway. In summary, these research findings offer potential molecular markers for the diagnosis and prognosis of BC, with the discovery of PPP2R2B particularly holding significant biological and clinical significance. This study provides valuable clues for future in-depth investigations into the molecular mechanisms of BC, as well as the development of new diagnostic markers and therapeutic targets.

Molecular Screening for Urothelial Cancer: How Close We Are?

Early detection of urothelial cancer offers the potential for effective and successful treatment. Despite previous efforts, currently, there is not a well-validated, recommended screening program in any country. This integrative, literature-based review provides details on how recent molecular advances may further advance early tumor detection. The minimally invasive liquid biopsy is capable of identifying tumor material in human fluid samples from asymptomatic individuals. Circulating tumor biomarkers (cfDNA, exosomes, etc.) are very promising and are attracting the interest of numerous studies for the diagnosis of early-stage cancer. However, this approach definitely needs to be refined before clinical implementation. Nevertheless, despite the variety of current obstacles that require further research, the prospect of identifying urothelial carcinoma by a single urine or blood test seems truly intriguing.

Non-coding RNA and autophagy: Finding novel ways to improve the diagnostic management of bladder cancer

Major fraction of the human genome is transcribed in to the RNA but is not translated in to any specific functional protein. These transcribed but not translated RNA molecules are called as non-coding RNA (ncRNA). There are thousands of different non-coding RNAs present inside the cells, each regulating different cellular pathway/pathways. Over the last few decades non-coding RNAs have been found to be involved in various diseases including cancer. Non-coding RNAs are reported to function both as tumor enhancer and/or tumor suppressor in almost each type of cancer. Urothelial carcinoma of the urinary bladder is the second most common urogenital malignancy in the world. Over the last few decades, non-coding RNAs were demonstrated to be linked with bladder cancer progression by modulating different signalling pathways and cellular processes such as autophagy, metastasis, drug resistance and tumor proliferation. Due to the heterogeneity of bladder cancer cells more in-depth molecular characterization is needed to identify new diagnostic and treatment options. This review emphasizes the current findings on non-coding RNAs and their relationship with various oncological processes such as autophagy, and their applicability to the pathophysiology of bladder cancer. This may offer an understanding of evolving non-coding RNA-targeted diagnostic tools and new therapeutic approaches for bladder cancer management in the future.

Identification of Potential microRNA Panels for Male Non-Small Cell Lung Cancer Identification Using Microarray Datasets and Bioinformatics Methods

Background: Non-small cell lung cancer (NSCLC) is still one of the types of cancer with the highest death rates. MicroRNAs (miRNAs) play essential roles in NSCLC development. This study evaluates miRNA expression patterns and specific mechanisms in male patients with NSCLC. Methods: We report an integrated microarray analysis of miRNAs for eight matched samples of males with NSCLC compared to the study of public datasets of males with NSCLC from TCGA, followed by qRT-PCR validation. Results: For the TCGA dataset, we identified 385 overexpressed and 75 underexpressed miRNAs. Our cohort identified 54 overexpressed and 77 underexpressed miRNAs, considering a fold-change (FC) of ±1.5 and p < 0.05 as the cutoff value. The common miRNA signature consisted of eight overexpressed and nine underexpressed miRNAs. Validation was performed using qRT-PCR on the tissue samples for miR-183-3p and miR-34c-5p and on plasma samples for miR-34c-5p. We also created mRNA-miRNA regulatory networks to identify critical molecules, revealing NSCLC signaling pathways related to underexpressed and overexpressed transcripts. The genes targeted by these transcripts were correlated with overall survival. Conclusions: miRNAs and some of their target genes could play essential roles in investigating the mechanisms involved in NSCLC evolution and provide opportunities to identify potential therapeutic targets.

The circular RNA circFARSA sponges microRNA-330-5p in tumor cells with bladder cancer phenotype

Background

Circular RNAs (circRNAs) modulate gene expression in various malignancies. However, their roles in the occurrence of bladder cancer (BC) and their underlying mechanisms of action are currently unclear.

Methods

We measured levels of the circRNA phenylalanyl-tRNA synthetase subunit alpha (circFARSA) and target microRNAs (miRNAs/miRs) in BC tissues and cell lines using quantitative polymerase chain reactions. The functions of circFARSA in tumor formation were examined in mice with BC xenografts in vivo and in BC cells via determination of their proliferation, activity, apoptosis, metastasis, and invasion in vitro using cell counting kit-8 assays, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays, flow cytometry, western blotting, Transwell assays, and cell wound healing assays. Interactions between miR-330 and circFARSA were predicted and confirmed by bioinformatic processing and dual-luciferase reporter gene assays, respectively. Expression profiles of miR-330 targets in BC cells were assessed via western blotting.

Results

circFARSA expression was markedly upregulated in BC tissues and cell lines compared with that in normal bladder samples. Silencing circFARSA expression decreased BC cell proliferation, invasion, and migration but induced their apoptosis in vitro. Downregulating circFARSA expression slowed tumor growth in vivo and directly sponged miR-330 and inhibited its function in BC cells in vitro. Inhibiting miR-330 expression abolished the regulatory effects of circFARSA silencing on the tumor phenotypes of BC cells.

Conclusions

circFARSA expression is upregulated and exerts oncogenic functions in BC by sponging miR-330.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09467-7.

Analysis of lung cancer-related genetic changes in long-term and low-dose polyhexamethylene guanidine phosphate (PHMG-p) treated human pulmonary alveolar epithelial cells

BACKGROUND

Lung injury elicited by respiratory exposure to humidifier disinfectants (HDs) is known as HD-associated lung injury (HDLI). Current elucidation of the molecular mechanisms related to HDLI is mostly restricted to fibrotic and inflammatory lung diseases. In our previous report, we found that lung tumors were caused by intratracheal instillation of polyhexamethylene guanidine phosphate (PHMG-p) in a rat model. However, the lung cancer-related genetic changes concomitant with the development of these lung tumors have not yet been fully defined. We aimed to discover the effect of long-term exposure of PHMG-p on normal human lung alveolar cells.

METHODS

We investigated whether PHMG-p could increase distorted homeostasis of oncogenes and tumor-suppressor genes, with long-term and low-dose treatment, in human pulmonary alveolar epithelial cells (HPAEpiCs). Total RNA sequencing was performed with cells continuously treated with PHMG-p and harvested after 35 days.

RESULTS

After PHMG-p treatment, genes with transcriptional expression changes of more than 2.0-fold or less than 0.5-fold were identified. Within 10 days of exposure, 2 protein-coding and 5 non-coding genes were selected, whereas in the group treated for 27-35 days, 24 protein-coding and 5 non-coding genes were identified. Furthermore, in the long-term treatment group, 11 of the 15 upregulated genes and 9 of the 14 downregulated genes were reported as oncogenes and tumor suppressor genes in lung cancer, respectively. We also found that 10 genes of the selected 24 protein-coding genes were clinically significant in lung adenocarcinoma patients.

CONCLUSIONS

Our findings demonstrate that long-term exposure of human pulmonary normal alveolar cells to low-dose PHMG-p caused genetic changes, mainly in lung cancer-associated genes, in a time-dependent manner.

MicroRNA Dysregulation in Prostate Cancer

Prostate cancer biology is complex, and needs to be deciphered. The latest evidence reveals the significant role of non-coding RNAs, particularly microRNAs (miRNAs), as key regulatory factors in cancer. Therefore, the identification of altered miRNA patterns involved in prostate cancer will allow them to be used for development of novel diagnostic and prognostic biomarkers. Patients and Methods: We performed a miRNAs transcriptomic analysis, using microarray (10 matched pairs tumor tissue versus normal adjacent tissue, selected based on inclusion criteria), followed by overlapping with TCGA data. A total of 292 miRNAs were differentially expressed, with 125 upregulated and 167 downregulated in TCGA patients’ cohort with PRAD (prostate adenocarcinoma), respectively for the microarray experiments; 16 upregulated and 44 downregulated miRNAs were found in our cohort. To confirm our results obtained for tumor tissue, we performed validation with qRT-PCR at the tissue and plasma level of two selected transcripts, and finally, we focused on the identification of altered miRNAs involved in key biological processes. Results: A common signature identified a panel of 12 upregulated and 1 downregulated miRNA, targeting and interconnected in a network with the TP53, AGO2, BIRC5 gene and EGFR as a core element. Among this signature, the overexpressed transcripts (miR-20b-5p, miR-96-5p, miR-183-5p) and the downregulated miR-542-5p were validated by qRT-PCR in an additional patients’ cohort of 34 matched tumor and normal adjacent paired samples. Further, we performed the validation of the expression level for miR-20b-5p, miR-96-5p, miR-183-5p plasma, on the same patients’ cohort versus a healthy control group, confirming the overexpression of these transcripts in the PRAD group, demonstrating the liquid biopsy as a potential investigational tool in prostate cancer. Conclusion: In this pilot study, we provide evidence on miRNA dysregulation and its association with key functional components of the PRAD landscape, where an important role is acted by miR-20b-5p, miR-542-5p, or the oncogenic cluster miR-183-96-182.

Identification of a Nomogram from Ferroptosis-Related Long Noncoding RNAs Signature to Analyze Overall Survival in Patients with Bladder Cancer

Purpose

This study aimed to establish a nomogram to predict the overall survival (OS) of patients with bladder cancer (BC) by ferroptosis-related long noncoding RNAs (FRlncRNAs) signature.

Methods

We obtained FRlncRNAs expression profiles and clinical data of patients with BC from the Cancer Genome Atlas database. The patients were divided into the training set, testing set, and overall set. Lasso regression and multivariate Cox regression were used to establish the FRlncRNAs signature, the prognosis of each group was compared by Kaplan–Meier (K-M) analysis, and the receiver operating characteristic (ROC) curve evaluated the accuracy of the model. The Gene Set Enrichment Analysis (GSEA) was used for the visualization of the functional enrichment for FRlncRNAs. The databases of GEPIA and K-M Plotter were used for subsequent functional analysis of major FRlncRNAs.

Results

Thirteen prognostic FRlncRNAs (LINC00942, MAFG-DT, AL049840.3, AL136084.3, OCIAD1-AS1, AC062017.1, AC008074.2, AC018653.3, AL031775.1, USP30-AS1, LINC01767, AC132807.2, and AL354919.2) were identified to be significantly different, constituting an FRlncRNAs signature. Patients with BC were divided into low-risk group and high-risk group by this signature in the training, testing, and overall sets. K-M analysis showed that the prognosis of patients in the high-risk group was poor and the difference in the subgroup analyses was statistically significant. ROC analysis revealed that the predictive ability of the model was more accurate than traditional assessment methods. A risk score based on FRlncRNAs signature was an independent prognostic factor for the patients with BC (HR = 1.388, 95%CI = 1.228–1.568, P < 0.001). Combining the FRlncRNAs signature and clinicopathological factors, a predictive nomogram was constructed. The nomogram can accurately predict the overall survival of patients and had high clinical practicability. The GSEA analysis showed that the primary pathways were WNT, MAPK, and cell-matrix adhesion signaling pathways. The major FRlncRNAs (MAFG-DT) were associated with poor prognosis in the GEPIA and K-M Plotter database.

Conclusion

Thirteen prognostic FRlncRNAs and their nomogram were accurate tools for predicting the OS of BC, which might be molecular biomarkers and therapeutic targets.

LncRNA HAND2-AS1 exerts anti-oncogenic effects on bladder cancer via restoration of RARB as a sponge of microRNA-146

Background

Growing evidence has shown that long noncoding RNA: microRNA: mRNA is implicated in tumor initiation, development, and progression. Long noncoding RNA HAND2-AS1 exhibits anti-cancer effects in diverse cancers. However, the knowledge of HAND-AS1 in bladder cancer development remains unknown.

Methods

LncRNA and miRNA microarray was conducted to explore different expressed RNA in primary bladder cancer specimens. RNA-RNA interaction prediction tools miRcode (http://www.mircode.org/), DIANA-lncBase v2 (https://carolina.imis.athena-innovation.gr/diana_tools/web/index.php?r=lncbasev2%2Findex-experimental), DIANA-TarBase v.8 (https://carolina.imis.athena-innovation.gr/diana_tools/web/index.php?r=tarbasev8%2Findex) and miRDB (http://www.mirdb.org/) were employed to predict the interactions between RNA. Bladder cancer cell lines were used to perform cell proliferation and apoptosis assays. Western blot and quantitative Real-time Polymerase Chain Reaction were used to determine the expression of protein and RNA separately. Dual-luciferase assay was conducted to determine the activity of three prime untranslated region of retinoic acid receptor beta (RARB). Furthermore, 5637 human bladder cancer mouse models were established to investigate the interactions of lncRNA: miRNA: mRNA in vivo.

Results

Based on the RT2 lncRNA PCR Arrays analysis, we validated HAND2-AS1 declined in bladder cancer and negatively correlated with the depth of invasion and grades. The overexpression of HAND2-AS1 in human bladder cancer cells 5637 and RT4 hampered cell proliferation by provoking Caspase 3-triggered cell apoptosis. Besides, one of the HAND2-AS1 sponges, miR-146, elevated in bladder cancer and targeted the tumor suppressor, retinoic acid receptor beta (RARB). We further demonstrated that the HAND2-AS1: miR-146: RARB complex promoted Caspase 3-mediated apoptosis by suppressing COX-2 expression. Finally, the results gained in mouse xenografts suggested that HAND2-AS1 diminished miR-146 expression, thereby reversing the suppression of miR-146 on RARB-mediated apoptosis and contributing to bladder cancer regression.

Conclusion

The present study sheds light on the fact that lncRNA HAND2-AS1 exerted as a tumor suppressor by releasing RARB from miR-146, leading to tumor proliferation and invasion inhibition. The findings expanded HAND2-AS-mediated regulatory networks' knowledge and provided novel insights to improve the RARB-targeted regimens against bladder cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02063-y.

Epithelial-Mesenchymal Transition Gene Signature Related to Prognostic in Colon Adenocarcinoma

Colon adenocarcinoma (COAD) remains an important cause of cancer-related mortality worldwide. Epithelial–mesenchymal transition (EMT) is a key mechanism, promoting not only the invasive or metastatic phenotype but also resistance to therapy. Using bioinformatics approaches, we studied the alteration on EMT related genes and its implication on COAD prognostic based on public datasets. For the EMT mechanisms, two overexpressed genes were identified (NOX4 and IGF2BP3), as well as five downregulated genes (BMP5, DACT3, EEF1A2, GCNT2 and SFRP1) that were related to prognosis in COAD. A qRT-PCR validation step was conducted in a COAD patient cohort comprising of 29 tumor tissues and 29 normal adjacent tissues, endorsing the expression level for BMP5, as well as for two of the miRNAs targeting key EMT related genes, revealing upregulation of miR-27a-5p and miR-146a-5p. The EMT signature can be used to develop a panel of biomarkers for recurrence prediction in COAD patients, which may contribute to the improvement of risk stratification for the patients.

Hsa-miR-125b Therapeutic Role in Colon Cancer Is Dependent on the Mutation Status of the TP53 Gene

Colon cancer is the third most common cancer type worldwide and is highly dependent on DNA mutations that progressively appear and accumulate in the normal colon epithelium. Mutations in the TP53 gene appear in approximately half of these patients and have significant implications in disease progression and response to therapy. miR-125b-5p is a controversial microRNA with a dual role in cancer that has been reported to target specifically TP53 in colon adenocarcinomas. Our study investigated the differential therapeutic effect of miR-125b-5p replacement in colon cancer based on the TP53 mutation status of colon cancer cell lines. In TP53 mutated models, miR-125b-5p overexpression slows cancer cells’ malignant behavior by inhibiting the invasion/migration and colony formation capacity via direct downregulation of mutated TP53. In TP53 wild type cells, the exogenous modulation of miR-125b-5p did not significantly affect the molecular and phenotypic profile. In conclusion, our data show that miR-125b-5p has an anti-cancer effect only in TP53 mutated colon cancer cells, explaining partially the dual behavior of this microRNA in malignant pathologies.

The VIM-AS1/miR-655/ZEB1 axis modulates bladder cancer cell metastasis by regulating epithelial-mesenchymal transition

BACKGROUND

Invasive bladder tumors cause a worse prognosis in patients and remain a clinical challenge. Epithelial-mesenchymal transition (EMT) is associated with bladder cancer metastasis. In the present research, we attempted to demonstrate a novel mechanism by which a long noncoding RNA (lncRNA)-miRNA-mRNA axis regulates EMT and metastasis in bladder cancer.

METHODS

Immunofluorescence (IF) staining was used to detect Vimentin expression. The protein expression of ZEB1, Vimentin, E-cadherin, and Snail was investigated by using immunoblotting assays. Transwell assays were performed to detect the invasive capacity of bladder cancer cells. A wound healing assay was used to measure the migratory capacity of bladder cancer cells.

RESULTS

Herein, we identified lncRNA VIM-AS1 as a highly- expressed lncRNA in bladder cancer, especially in metastatic bladder cancer tissues and high-metastatic bladder cancer cell lines. By acting as a ceRNA for miR-655, VIM-AS1 competed with ZEB1 for miR-655 binding, therefore eliminating the miR-655-mediated suppression of ZEB1, finally promoting EMT in both high- and low-metastatic bladder cancer cells and enhancing cancer cell metastasis.

CONCLUSIONS

In conclusion, the VIM-AS1/miR-655/ZEB1 axis might be a promising target for improving bladder cancer metastasis via an EMT-related mechanism.

Liquid Biopsy Biomarkers in Urine: A Route towards Molecular Diagnosis and Personalized Medicine of Bladder Cancer

Bladder cancer (BC) is characterized by high incidence and recurrence rates together with genomic instability and elevated mutation degree. Currently, cystoscopy combined with cytology is routinely used for diagnosis, prognosis and disease surveillance. Such an approach is often associated with several side effects, discomfort for the patient and high economic burden. Thus, there is an essential demand of non-invasive, sensitive, fast and inexpensive biomarkers for clinical management of BC patients. In this context, liquid biopsy represents a very promising tool that has been widely investigated over the last decade. Liquid biopsy will likely be at the basis of patient selection for precision medicine, both in terms of treatment choice and real-time monitoring of therapeutic effects. Several different urinary biomarkers have been proposed for liquid biopsy in BC, including DNA methylation and mutations, protein-based assays, non-coding RNAs and mRNA signatures. In this review, we summarized the state of the art on different available tests concerning their potential clinical applications for BC detection, prognosis, surveillance and response to therapy.

Comprehensive Analysis of the Expression of Key Genes Related to Hippo Signaling and Their Prognosis Impact in Ovarian Cancer

The Hippo signaling pathway, one of the most conserved in humans, controlling dimensions of organs and tumor growth, is frequently deregulated in several human malignancies, including ovarian cancer (OC). The alteration of Hippo signaling has been reported to contribute to ovarian carcinogenesis and progression. However, the prognostic roles of individual Hippo genes in OC patients remain elusive. Herein we investigated the expression level and prognostic value of key Hippo genes in OC using online databases, followed by a qRT-PCR validation step in an additional patient cohort. Using the GEPIA database, we observed an increased level for TP53 and reduced expression level for LATS1, LATS2, MST1, TAZ, and TEF in tumor tissue versus normal adjacent tissue. Moreover, LATS1, LATS2, TP53, TAZ, and TEF expression levels have prognostic significance correlated with progression-free survival. The qRT-PCR validation step was conducted in an OC patient cohort comprising 29 tumor tissues and 20 normal adjacent tissues, endorsing the expression level for LATS1, LATS2, and TP53, as well as for two of the miRNAs targeting the TP53 gene, revealing miR-25-3p upregulation and miR-181c-5p downregulation. These results display that there are critical prognostic value dysregulations of the Hippo genes in OC. Our data demonstrate the major role the conserved Hippo pathway presents in tumor control, underlying potential therapeutic strategies and controlling several steps modulated by miRNAs and their target genes that could limit ovarian cancer progression.

circFOXO3: Going around the mechanistic networks in cancer by interfering with miRNAs regulatory networks

Circular RNAs (circRNA) have gained recent interest due to their functional versatility due to their interactions with other RNA species and proteins, all of which underline complex regulatory networks involved in pathogenic mechanisms. As a result, recent insights in circRNA biology are investigating their biomarker and therapeutic potential. One such circRNA is CircFOXO3, which consists of the circularized second exon of the FOXO3 mRNA, a member of the forkhead box transcription factor family involved in the regulation of developmental programs. Recent research focused on the role of circFOXO3 in the context of cancer has highlighted several implications in key tumorigenesis mechanisms, thus consolidating its relevance among other identified circRNAs. In this paper, we will focus on the currently identified case-specific implications of circFOXO3 in cancer, with a focus on the circFOXO3-miRNA-mRNA regulatory networks, its interactions with different proteins, and their cumulated biological effects upon tumor development. Therefore, we aim to provide an integrated perspective of the mechanistic implications of circFOXO3 in different cancers while also highlighting its biomarker or therapeutic potential based on the current evidence.

Lower mutant-allele tumor heterogeneity is a biomarker in FGFR3-mutant bladder cancer for better prognosis

Background

Bladder cancer displays a broad mutational spectrum and intratumor heterogeneity (ITH), which results in difference in molecular phenotypes and resistance to therapies. However, there are currently no clinically available measures to predict patient prognosis using ITH. We aimed to establish a clinically relevant biomarker by using ITH for informing predictive of outcomes.

Methods

We used the Bioconductor R package Maftools to efficiently and comprehensively analyze somatic variants of muscle-invasive bladder cancer (MIBC) from The Cancer Genome Atlas (TCGA). We then used a mutant-allele tumor heterogeneity (MATH) algorithm to measure ITH and explored its correlation with clinical parameters as well as mutational subtypes.

Results

We observed a broad range of somatic mutations in MIBC from TCGA. MATH value was higher for the high-grade group than for the low-grade group (p < 0.05). There was a strong correlation between higher MATH value and presence of TP53 mutations (p = 0.008), as well as between lower MATH value and presence of FGFR3 mutations (p = 0.006). Patients with FGFR3 mutation and low MATH value exhibit longer overall survival time than that of all BLCA patients (p = 0.044), which was replicated in another bladder cancer database composed of 109 BLCA patients.

Conclusion

Measures of tumor heterogeneity may be useful biomarkers for identifying patients with bladder cancer. Low MATH value was an independent risk factor that predicted better prognosis for patients with FGFR3 mutation compared to all BLCA patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-020-02084-3.

New insights in gene expression alteration as effect of doxorubicin drug resistance in triple negative breast cancer cells

BACKGROUND

Triple negative breast cancer (TNBC) is a heterogeneous disease with aggressive behavior and an unfavorable prognosis rate. Due to the lack of surface receptors, TNBC must be intensely investigated in order to establish a suitable treatment for patients with this pathology. Chemoresistance is an important reason for therapeutic failure in TNBC.

METHOD

The aim of this study was to investigate the effect of doxorubicin in TNBC cell lines and to highlight cellular and molecular alterations after a long exposure to doxorubicin.

RESULTS

The results revealed that doxorubicin significantly increased the half maximal inhibitory concentration (IC50) values at P12 and P24 compared to parenteral cells P0. Modifications in gene expression were investigated through microarray technique, and for detection of mutational pattern was used Next Generation Sequencing (NGS). 196 upregulated and 115 downregulated genes were observed as effect of multiple dose exposure, and 15 overexpressed genes were found to be involved in drug resistance. Also, the presence of some additional mutations in both cell lines was observed.

CONCLUSION

The outcomes of this research may provide novel biomarkers for drug resistance in TNBC. Also, this activity can highlight the potential mechanisms associated with drug resistance, as well as the potential therapies to counteract these mechanisms.

Cancer-Associated Stemness and Epithelial-to-Mesenchymal Transition Signatures Related to Breast Invasive Carcinoma Prognostic

Simple Summary

Breast cancer is one of the most common oncological diseases in women, as its incidence is rapidly growing. In this study, we have investigated the mechanism of epithelial-to-mesenchymal transition (EMT) and cancer stem cells (CSCs), demonstrating presence of an interconnectedness between them. This interconnectedness plays important roles in patient prognostic, as well as in diagnostic and therapeutic targets. It is identified that there is a common signature between CSCs and EMT, and this is represented by ALDH1A1, SFRP1, miR-139, miR-21, and miR-200c. This finding will provide a better understanding of this mechanism, and will facilitate the development of novel treatment options.

Abstract

Breast cancer is one of the most common oncological diseases in women, as its incidence is rapidly growing, rendering it unpredictable and causing more harm than ever before on an annual basis. Alterations of coding and noncoding genes are related to tumorigenesis and breast cancer progression. In this study, several key genes associated with epithelial-to-mesenchymal transition (EMT) and cancer stem cell (CSC) features were identified. EMT and CSCs are two key mechanisms responsible for self-renewal, differentiation, and self-protection, thus contributing to drug resistance. Therefore, understanding of the relationship between these processes may identify a therapeutic vulnerability that can be further exploited in clinical practice, and evaluate its correlation with overall survival rate. To determine expression levels of altered coding and noncoding genes, The Cancer Omics Atlas (TCOA) are used, and these data are overlapped with a list of CSCs and EMT-specific genes downloaded from NCBI. As a result, it is observed that CSCs are reciprocally related to EMT, thus identifying common signatures that allow for predicting the overall survival for breast cancer genes (BRCA). In fact, common CSCs and EMT signatures, represented by ALDH1A1, SFRP1, miR-139, miR-21, and miR-200c, are deemed useful as prognostic biomarkers for BRCA. Therefore, by mapping changes in gene expression across CSCs and EMT, suggesting a cross-talk between these two processes, we have been able to identify either the most common or specific genes or miRNA markers associated with overall survival rate. Thus, a better understanding of these mechanisms will lead to more effective treatment options.

STAT3-Induced Upregulation of lncRNA CASC9 Promotes the Progression of Bladder Cancer by Interacting with EZH2 and Affecting the Expression of PTEN

Objective

Long non-coding RNA (lncRNA) cancer susceptibility candidate 9 (CASC9) has been reported to play a vital role in tumorigenesis. This study explored the biological role of CASC9 and its regulation mechanism in bladder cancer (BC).

Methods

Gene expression was evaluated using quantitative reverse transcription polymerase chain reaction and Western blot. The functional role of CASC9 in BC was studied using Cell Counting Kit-8, colony formation assay, scratch wound healing assay, transwell invasion assay, and xenograft tumor assay. In addition, the mechanism of CASC9 function in BC was determined using RNA immunoprecipitation assay and chromatin immunoprecipitation assay.

Results

CASC9 was upregulated in BC tissues and cell lines, and correlated with the staging and metastasis in BC. Knockdown of CASC9 inhibited the proliferation, migration, and invasion of BC cells. Similarly, silencing of CASC9 inhibited tumor growth in vivo. Signal transducer and activator of transcription 3 (STAT3) was upregulated in BC tissues and cell lines, and positively correlated with CASC9 in BC tissues. Moreover, CASC9 was shown to be regulated by STAT3 in BC cells. Furthermore, CASC9 regulated phosphatase and tensin homolog (PTEN) expression by interacting with enhancer of zeste homolog 2 (EZH2). More significantly, CASC9 silencing-mediated inhibition of BC progression was partly reversed by EZH2 overexpression or PTEN inhibition.

Conclusion

Upregulation of CASC9 induced by STAT3 promoted the progression of BC by interacting with EZH2 and affecting the expression of PTEN, representing a novel regulatory mechanism for BC progression.

Knockdown of lncRNA ZNRD1-AS1 inhibits progression of bladder cancer by regulating miR-194 and ZEB1

BACKGROUND

Bladder cancer (BC) is a common urinary neoplasm with high incidence worldwide. Long noncoding RNA zinc ribbon domain containing 1 antisense RNA 1 (ZNRD1-AS1) has been reported to be upregulated in BC. However, the exact role of ZNRD1-AS1 as well as its mechanism remains poorly understood.

METHODS

Zinc ribbon domain containing 1 antisense RNA 1, and its potential downstream genes microRNA-194 (miR-194) and zinc finger E-box binding homeobox 1 (ZEB1) levels were detected via quantitative real-time polymerase chain reaction or western blot. Cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) were detected to assess the influences of ZNRD1-AS1, miR-194 and ZEB1 on BC cells by colony formation, cell counting kit-8 (CCK-8), transwell analysis or western blot. The relationship between miR-194 and ZNRD1-AS1 or ZEB1 was analyzed by luciferase activity analysis. The xenograft experiment was performed to assess the function of ZNRD1-AS1 in vivo.

RESULTS

Zinc ribbon domain containing 1 antisense RNA 1level was upregulated in BC. ZNRD1-AS1 silence repressed proliferation, migration, invasion and EMT in BC cells. MiR-194 was identified as a target of ZNRD1-AS1, and miR-194 upregulation repressed proliferation, migration, invasion, and EMT by ZNRD1-AS1 sponging. ZEB1 was targeted via miR-194 and its interference impeded proliferation, migration, invasion, and EMT. Moreover, ZNRD1-AS1 regulated ZEB1 expression via miR-194. Besides, inhibition of ZNRD1-AS1 attenuated tumor growth by miR-194/ZEB1 axis in vivo.

CONCLUSION

Knockdown of ZNRD1-AS1 suppressed BC cell development in vitro and in vivo via targeting miR-194 to regulate ZEB1, indicating a novel avenue for treatment of BC.

Natural compounds modulate the crosstalk between apoptosis- and autophagy-regulated signaling pathways: Controlling the uncontrolled expansion of tumor cells

Due to the high number of annual cancer-related deaths, and the economic burden that this malignancy affects today's society, the study of compounds isolated from natural sources should be encouraged. Most cancers are the result of a combined effect of lifestyle, environmental factors, and genetic and hereditary components. Recent literature reveals an increase in the interest for the study of phytochemicals from traditional medicine, this being a valuable resource for modern medicine to identify novel bioactive agents with potential medicinal applications. Phytochemicals are components of traditional medicine that are showing promising application in modern medicine due to their antitumor activities. Recent studies regarding two major mechanisms underlying cancer development and regulation, apoptosis and autophagy, have shown that the signaling pathways of both these processes are significantly interconnected through various mechanisms of crosstalk. Phytochemicals are able to activate pro-autophagic and pro-apoptosis mechanisms. Understanding the molecular mechanism involved in apoptosis-autophagy relationship modulated by phytochemicals plays a key role in development of a new therapeutic strategy for cancer treatment. The purpose of this review is to outline the bioactive properties of the natural phytochemicals with validated antitumor activity, focusing particularly on their role in the regulation of apoptosis and autophagy crosstalk that triggers the uncontrolled expansion of tumor cells. Furthermore, we have also critically discussed the limitations and challenges of existing research strategies and the prospective research directions in this field.

Macrophages Interaction and MicroRNA Interplay in the Modulation of Cancer Development and Metastasis

Advancement in cancer research has shown that the tumor microenvironment plays a crucial role in the installation, progression, and dissemination of cancer cells. Among the heterogeneous panel of cells within the malignant microenvironment are tumor-associated macrophages that are sustaining the malignant cells through strict feedback mechanisms and spatial distribution. Considering that the presence of metastasis is one of the main feature associated with decreased survival rates among patients, in the present article we briefly present the involvement of tumor-associated macrophages in the hallmarks of metastasis and their microRNA-related regulation with a focus on lung cancer in order to coordinate the vast information under one pathology. As shown, these cells have emerged as coordinators of immunosuppression, angiogenesis and lymphangiogenesis, vessel intravasation and extravasation of cancer cells, and premetastatic niche formation, transforming the macrophages in potential therapeutic targets and also prognostic markers according to their density within the tumor and polarization phenotype. An indirect therapeutic approach on tumor-associated macrophages can be also represented by regulation of microRNAs involved in their polarization and implicit oncogenic features. Examples of these microRNAs consist in the highly studied miR-21 and miR-155, but also other microRNA with less feedback in the literature: miR-1207-5p, miR-193b, miR-320a, and others.

Non-coding RNA in bladder cancer

Bladder cancer is the tenth most common cancer worldwide and has been associated with high mortality and morbidity. Although the treatment of bladder cancer is based on well-defined tumor classifications and gradings, patients still experience different clinical response. The heterogeneity of this disease calls for substantial research with more in-depth molecular characterization, with the hope of identifying new diagnostic and treatment options. In recent years, non-coding RNAs (ncRNAs), particularly, microRNAs (miRNAs), long non-coding RNA (lncRNAs), and circular RNAs (circRNAs) were found to be associated with bladder cancer occurrence and development. This review highlights the recent findings concerning ncRNAs and their relevance to the pathogenesis of bladder cancer. This may provide a foundation for developing highly specific diagnostic tools and more robust therapeutic strategies in the future.

Unraveling UCA1 lncRNA prognostic utility in urothelial bladder cancer

In the era of precision oncology, bladder cancer (BlCa) is characterized by generic patient management and lack of personalized prognosis and surveillance. Herein, we have studied the clinical significance of urothelial cancer associated 1 (UCA1) lncRNA in improving patients' risk stratification and prognosis. A screening cohort of 176 BlCa patients was used for UCA1 quantification. The Hedegaard et al. (n = 476) and The Cancer Genome Atlas (TCGA) provisional (n = 413) were analyzed as validation cohorts for non-muscle-invasive bladder cancer (NMIBC) and muscle-invasive bladder cancer (MIBC), respectively. Patients' survival outcome was assessed using recurrence and progression for NMIBC or death for MIBC as clinical endpoint events. Bootstrap analysis was performed for internal validation of Cox regression analysis, whereas the clinical benefit of disease prognosis was assessed by decision curve analysis. UCA1 was significantly overexpressed in bladder tumors compared with normal urothelium, which was confirmed only in the case of NMIBC. Interestingly, reduced expression of UCA1 was correlated with muscle-invasive disease as well as with tumors of higher stage and grade. UCA1 loss was strongly associated with higher risk of short-term relapse [hazard ratio (HR) = 1.974; P = 0.032] and progression to invasive stages (HR = 3.476; P = 0.023) in NMIBC. In this regard, Hedegaard et al. and TCGA validation cohorts confirmed the unfavorable prognostic nature of UCA1 loss in BlCa. Finally, prognosis prediction models integrating UCA1 underexpression and established clinical disease markers contributed to improved stratification specificity and superior clinical benefit for NMIBC prognosis. Underexpression of UCA1 correlates with worse disease outcome in NMIBC and contributes to superior prediction of disease early relapse and progression as well as improved patient stratification specificity.

Adipocyte-Based Cell Therapy in Oncology: The Role of Cancer-Associated Adipocytes and Their Reinterpretation as Delivery Platforms

Cancer-associated adipocytes have functional roles in tumor development through secreted adipocyte-derived factors and exosomes and also through metabolic symbiosis, where the malignant cells take up the lactate, fatty acids and glutamine produced by the neighboring adipocytes. Recent research has demonstrated the value of adipocytes as cell-based delivery platforms for drugs (or prodrugs), nucleic acids or loaded nanoparticles for cancer therapy. This strategy takes advantage of the biocompatibility of the delivery system, its ability to locate the tumor site and also the predisposition of cancer cells to come in functional contact with the adipocytes from the tumor microenvironment for metabolic sustenance. Also, their exosomal content can be used in the context of cancer stem cell reprogramming or as a delivery vehicle for different cargos, like non-coding nucleic acids. Moreover, the process of adipocytes isolation, processing and charging is quite straightforward, with minimal economical expenses. The present review comprehensively presents the role of adipocytes in cancer (in the context of obese and non-obese individuals), the main methods for isolation and characterization and also the current therapeutic applications of these cells as delivery platforms in the oncology sector.

An Emerging Class of Long Non-coding RNA With Oncogenic Role Arises From the snoRNA Host Genes

The small nucleolar RNA host genes (SNHGs) are a group of long non-coding RNAs, which are reported in many studies as being overexpressed in various cancers. With very few exceptions, the SNHGs (SNHG1, SNHG3, SNHG5, SNHG6, SNHG7, SNHG12, SNHG15, SNHG16, SNHG20) are recognized as inducing increased proliferation, cell cycle progression, invasion, and metastasis of cancer cells, which makes this class of transcripts a viable biomarker for cancer development and aggressiveness. Through our literature research, we also found that silencing of SNHGs through small interfering RNAs or short hairpin RNAs is very effective in both in vitro and in vivo experiments by lowering the aggressiveness of solid cancers. The knockdown of SNHG as a new cancer therapeutic option should be investigated more in the future.

Critical function of circular RNAs in lung cancer

Lung cancer is one of the main causes of cancer-related death in the world, especially due to its frequency and ineffective therapeutically approaches in the late stages of the disease. Despite the recent advent of promising new targeted therapies, lung cancer diagnostic strategies still have difficulty in identifying the disease at an early stage. Therefore, the characterizations of more sensible and specific cancer biomarkers have become an important goal for clinicians. Circular RNAs (circRNAs), a type of RNA with covalently closed continuous loop structures that display high structural resistance and tissue specificity pointed toward a potential biomarker role. Current investigations have identified that circRNAs have a prominent function in the regulation of oncogenic pathways, by regulating gene expression both at transcriptional and post-transcriptional level. The aim of this review is to provide novel information regarding the implications of circRNAs in lung cancer, with an emphasis on the role in disease development and progression. Initially, we explored the potential utility of circRNAs as biomarkers, focusing on function, mechanisms, and correlation with disease progression in lung cancer. Further, we will describe the interaction between circRNAs and other non-coding species of RNA (particularly microRNA) and their biological significance in lung cancer. Describing the nature of these interactions and their therapeutic potential will provide additional insight regarding the altered molecular landscape of lung cancer and consolidate the potential clinical value of these circular transcripts. This article is categorized under: RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems RNA in Disease and Development > RNA in Disease RNA in Disease and Development > RNA in Development.

MiRNA-Based Inspired Approach in Diagnosis of Prostate Cancer

Prostate cancer is one of the most encountered cancer diseases in men worldwide and in consequence it requires the improvement of therapeutic strategies. For the clinical diagnosis, the standard approach is represented by solid biopsy. From a surgical point of view, this technique represents an invasive procedure that may imply several postoperative complications. To overcome these impediments, many trends are focusing on developing liquid biopsy assays and on implementing them in clinical practice. Liquid samples (blood, urine) are rich in analytes, especially in transcriptomic information provided by genetic markers. Additionally, molecular characterization regarding microRNAs content reveals outstanding prospects in understanding cancer progression mechanisms. Moreover, these analytes have great potential for prostate cancer early detection, more accurate prostate cancer staging and also for decision making respecting therapy schemes. However, there are still questionable topics and more research is needed to standardize liquid biopsy-based techniques.

MicroRNA profiling in kidney in pigs fed ochratoxin A contaminated diet

OTA is a toxic metabolite produced by fungus belonging to Aspergillus and Penicillium genera. Kidney is the main target of this toxin; OTA is considered as one of the etiological factors at the origin of the human Balkan endemic nephropathy. microRNA are short non-coding transcrips (18-22 nucleotides in length) regulating key cellular processes. Various miRNAs have been established to play important roles in development of renal carcinoma and urothelial cancer. The objective of this study is to analyse the miRNA profiling in the kidney of piglets experimentally intoxicated with feed contaminated with OTA. Fifteen piglets (five pigs/group) were randomly distributed into 3 groups, fed normal diet (Group 1: control), or diets contaminated with OTA in two concentrations: 50 μg OTA/kg feed (Group 2: 50 μg OTA/kg feed) or 200 μg OTA/kg feed (Group 3: 200 μg OTA/kg feed) for 28 days. At the end of the experiment blood samples were taken for serological analyses. Animals from control group and 200 μg OTA/kg feed were sacrificed and kidney samples were taken for histological and molecular analyses. As resulted from molecular profiling study there are 8 miRNA differentially expressed in OTA kidney vs control kidney, in which five miRNA were overexpressed in the kidney of OTA intoxicated animals: miR-497 (FC = 6.34), miR-133a-3p (FC = 5.75), miR-423-3p (FC = 5.48), miR-34a (FC = 1.68), miR-542-3p (1.65) while three miRNA were downregulated: miR-421-3p (FC = -3.96); miR-490 (FC = -3.87); miR-9840-3p (FC = -2.13). The altered miRNAs as effect of OTA are strongly connected to the engine of cancer, disturbing nodal points in different pathways, as TP53 signalling. This proof-of-concept study proves the actual utility of miRNAs as biomarkers of mycotoxin exposure, including OTA.

Urine Biopsy-Liquid Gold for Molecular Detection and Surveillance of Bladder Cancer

With recent advancements in a non-invasive approach to cancer diagnosis and surveillance, the term "liquid biopsy" has gained traction but is currently limited by technological challenges in identifying and isolating circulating tumor cells (CTCs), proteins, cell-free DNA (cfDNA), or other nucleic acids. Tumor tissue biopsy, especially in genitourinary (GU) system is sometimes inadequate and requires invasive surgical options, especially for upper tract urothelial cancer. Urine can prove to be "liquid gold" since it may be a more abundant source of tumor-derived material without the background noise; however, urine DNA (uDNA) may be associated with low mutant allele fraction (MAF). Molecular detection of mutations in uDNA requires a sensitive and accurate method of analysis that allows a high depth of sequencing while minimizing artifacts. Several sequencing approaches to address this hurdle using enhanced library preparation techniques such as Tagged amplicon deep sequencing (TAm-Seq), Safe-SeqS, FAST-SeqS, and CAPP-Seq approaches have been developed. Urine biopsy utilizing next-generation sequencing (NGS) can prove useful at all stages of urologic malignancy care, where urine can be collected to aid in clinical decision making through the identification of commonly known mutations, and potentially reduce or avoid all forms of invasive procedures.

Epigenetics of Bladder Cancer: Where Biomarkers and Therapeutic Targets Meet

Bladder cancer (BC) is the most common neoplasia of the urothelial tract. Due to its high incidence, prevalence, recurrence and mortality, it remains an unsolved clinical and social problem. The treatment of BC is challenging and, although immunotherapies have revealed potential benefit in a percentage of patients, it remains mostly an incurable disease at its advanced state. Epigenetic alterations, including aberrant DNA methylation, altered chromatin remodeling and deregulated expression of non-coding RNAs are common events in BC and can be driver events in BC pathogenesis. Accordingly, these epigenetic alterations are now being used as potential biomarkers for these disorders and are being envisioned as potential therapeutic targets for the future management of BC. In this review, we summarize the recent findings in these emerging and exciting new aspects paving the way for future clinical treatment of this disease.

The extensive role of miR-155 in malignant and non-malignant diseases

MicroRNAs (miRNAs) have rapidly emerged as key molecules in cancer initiation and development, showing the capability to regulate pivotal oncogenic pathways. MiR-155 has gathered an increased attention especially in oncology, but also in non-malignanat pathologies. Nowadays, this noncoding RNA is one of the most important miRNAs in cancer, due to the extensive signaling network associated with it, implication in immune system regulation and also deregulation in disease states. Therefore, numerous research protocols are focused on preclinical modulation of miR-155 for therapeutic purposes, or investigation of its dynamic expression for diagnostic/prognostic assessments, with the final intention of bringing this miRNA into the clinical setting. This review comprehensively presents the extended role of miR-155 in cancer and other pathologies, where its expression is dysregulated. Finally, we assess the future steps toward miR-155 based therapeutics.

Dark-matter matters: Discriminating subtle blood cancers using the darkest DNA

The confluence of deep sequencing and powerful machine learning is providing an unprecedented peek at the darkest of the dark genomic matter, the non-coding genomic regions lacking any functional annotation. While deep sequencing uncovers rare tumor variants, the heterogeneity of the disease confounds the best of machine learning (ML) algorithms. Here we set out to answer if the dark-matter of the genome encompass signals that can distinguish the fine subtypes of disease that are otherwise genomically indistinguishable. We introduce a novel stochastic regularization, ReVeaL, that empowers ML to discriminate subtle cancer subtypes even from the same ‘cell of origin’. Analogous to heritability, implicitly defined on whole genome, we use predictability (F₁score) definable on portions of the genome. In an effort to distinguish cancer subtypes using dark-matter DNA, we applied ReVeaL to a new WGS dataset from 727 patient samples with seven forms of hematological cancers and assessed the predictivity over several genomic regions including genic, non-dark, non-coding, non-genic, and dark. ReVeaL enabled improved discrimination of cancer subtypes for all segments of the genome. The non-genic, non-coding and dark-matter had the highest F₁ scores, with dark-matter having the highest level of predictability. Based on ReVeaL’s predictability of different genomic regions, dark-matter contains enough signal to significantly discriminate fine subtypes of disease. Hence, the agglomeration of rare variants, even in the hitherto unannotated and ill-understood regions of the genome, may play a substantial role in the disease etiology and deserve much more attention.

Many subtypes of cancer are unable to be distinguished based on their genomic profiles. With the ever-increasing use of sequencing, we now have the ability to look deeper into the genome and pick up on hidden signals in areas typically considered irrelevant to disease. To overcome the issue of rare variants and the vast amount of heterogeneity found in these non-coding sectors, we introduce a new algorithm capable of correcting for both challenges, ReVeaL. Using this approach, we are able to demonstrate that the non-coding regions of the genome have more signal for distinguishing subtle subtypes of disease compared to all the coding regions. Specifically, we show that the darkest unexplored genomic regions, the non-coding genome with no functional annotation whatsoever in the literature, have the strongest signal. Thus dark-matter does indeed matter and should not be ignored but rather considered for the continued pressing task of finding biomarkers of disease to adequately treat our patients.

lncRNA HOTTIP facilitates osteosarcoma cell migration, invasion and epithelial-mesenchymal transition by forming a positive feedback loop with c-Myc

Homeobox A transcript at the distal tip (HOTTIP) is an oncogenic long non-coding RNA in cancer. The aim of the present study was to investigate the function and mechanism of HOTTIP in the aggressive behaviors of human osteosarcoma (OS) cells. Expression levels of HOTTIP and epithelial-mesenchymal transition (EMT) markers were determined by reverse transcription-quantitative PCR. Cell invasive and migratory abilities were evaluated in vitro using Matrigel and wound healing assays, respectively. Knockdown of HOTTIP expression was achieved by small interfering RNA-mediated silencing. Overexpression of c-Myc was accomplished by transfecting cultured cells with a c-Myc overexpression plasmid. HOTTIP was demonstrated to be upregulated in OS tissues and cell lines; knockdown of HOTTIP inhibited OS cell migration, invasion and EMT, and suppressed c-Myc expression. In addition, overexpression of c-Myc increased HOTTIP expression and enhanced OS cell migration and invasion. HOTTIP promoted cell migration and invasion by upregulating c-Myc in OS. The positive feedback loop formed by HOTTIP and c-Myc may contribute to OS progression, and HOTTIP may act as a therapeutic target for OS.

The protean world of non-coding RNAs in glioblastoma

Non-coding ribonucleic acids (ncRNAs) are a diverse group of RNA molecules that are mostly not translated into proteins following transcription. We review the role of ncRNAs in the pathobiology of glioblastoma (GBM), and their potential applications for GBM therapy. Significant advances in our understanding of the protean manifestations of ncRNAs have been made, allowing us to better decipher the molecular complexity of GBM. A large number of regulatory ncRNAs appear to have a greater influence on the molecular pathology of GBM than thought previously. Importantly, also, a range of therapeutic approaches are emerging whereby ncRNA-based systems may be used to molecularly target GBM. The most successful of these is RNA interference, and some of these strategies are being evaluated in ongoing clinical trials. However, a number of limitations exist in the clinical translation of ncRNA-based therapeutic systems, such as delivery mechanisms and cytotoxicity; concerted research endeavors are currently underway in an attempt to overcome these. Ongoing and future studies will determine the potential practical role for ncRNA-based therapeutic systems in the clinical management of GBM. These applications may be especially promising, given that current treatment options are limited and prognosis remains poor for this challenging malignancy.

The Relevance of Mass Spectrometry Analysis for Personalized Medicine through Its Successful Application in Cancer "Omics"

Mass spectrometry (MS) is an essential analytical technology on which the emerging omics domains; such as genomics; transcriptomics; proteomics and metabolomics; are based. This quantifiable technique allows for the identification of thousands of proteins from cell culture; bodily fluids or tissue using either global or targeted strategies; or detection of biologically active metabolites in ultra amounts. The routine performance of MS technology in the oncological field provides a better understanding of human diseases in terms of pathophysiology; prevention; diagnosis and treatment; as well as development of new biomarkers; drugs targets and therapies. In this review; we argue that the recent; successful advances in MS technologies towards cancer omics studies provides a strong rationale for its implementation in biomedicine as a whole.

Long non‑coding RNA H19 regulates cell growth and metastasis via the miR‑22‑3p/Snail1 axis in gastric cancer

Gastric cancer (GC) is the fifth most prevalent type of malignancy and the third leading cause of cancer‑related mortality worldwide, with the prognosis of patients with late‑stage GC remaining at poor levels. Long non‑coding RNA (lncRNA) H19 (H19) is involved in the growth and metastasis of tumors, and it is upregulated under hypoxic conditions and in certain types of cancer; however, the underlying mechanisms of action of this lncRNA as regards the initiation and development of GC remain unknown. Thus, in the present study, we aimed to determine the role of lncRNA H19 in GC and to elucidate the underlying mechanisms. H19 was found to be upregulated in GC tissues and cells compared with the para‑cancerous tissues, and an elevated expression of H19 was associated with lymph node metastasis and TNM stage. Furthermore, the downregulation of H19 suppressed the proliferation, invasion, migration and epithelial‑mesenchymal transition of GC cells in vitro and suppressed tumor growth in vivo. H19 was also found to be able to bind with miR‑22‑3p, and H19‑induced cell growth and metastasis were shown to be reversed by the upregulation of miR‑22‑3p; the miR‑22‑3p level was found to inversely correlate with H19 expression in GC tissues. Furthermore, the overexpression of miR‑22‑3p notably suppressed the proliferation, migration and invasion of GC cells, and these effects were enhanced by the downregulation of Snail1. In addition, cell growth and metastasis induced by miR‑22‑3p downregulation were partially reversed by the knockdown of Snail1. Furthermore, a negative correlation was observed between the mRNA expression levels of miR‑22‑3p and Snail1 in GC tissues. On the whole, the findings of the present study revealed that H19 was upregulated in GC tissues, which promoted tumor growth and metastasis via the miR‑22‑3p/Snail1 signaling pathway. In summary, these findings provide novel insight into the potential regulatory roles of H19 in GC, and suggest that the H19/miR‑22‑3p/Snail1 axis may prove to be a promising therapeutic target for the treatment of patients with GC.

Emerging roles of long non-coding RNAs in cancer

Cancer is a physiological condition that has both the endogenous and exogenous influences on its progression. It originates from unusual cell growth, where the cells undergo massive genetic alterations, bypass the signaling machinery and compromise its genetic cohesion. Literature has well narrated the DNA damage studies including driver mutations that interfere with the treatment strategies. However, with evolving medical excellence, recent day studies are trying to unveil the contribution of RNAs in the progression of tumor malignancies. A number of non-coding RNAs have been identified as an active component in cancer genomics. This article aims to review the role of long non-coding RNAs in the spectra of cancers and its prognostic value as the biomarkers in molecular targeting with clinical utility and therapeutic beneficence.

miR-181a/b therapy in lung cancer: reality or myth?

Despite substantial progress in oncology, lung cancer remains the number one malignancy in terms of both incidence and mortality rates, and there thus remains an urgent need for new therapeutic alternatives. MicroRNA (miRNA) have an important role in cancer initiation and progression due to their capacity to interfere with transcriptional signaling and regulate key cellular processes. miR-181a and miR-181b (miR-181a/b), which are located on chromosomes 1 and 9, are pathologically expressed in the tumor tissue and plasma of patients diagnosed with lung cancer. The miR-181a/b regulatory mechanisms are sophisticated and are directly related to different target genes. In recent years, an ever-increasing number of studies have focused on the biological relevance of miR-181a/b in key cellular processes. In this paper, we aim to discuss the challenging experimental data related to miR-181a/b and their potential use for the development of new therapeutic approaches in lung cancer. We will further present the ongoing issues regarding the regulation of their multiple target genes, and their potential use as biomarkers and therapeutic targets in this deadly malignancy.

Overview upon miR-21 in lung cancer: focus on NSCLC

Considering the high mortality rate encountered in lung cancer, there is a strong need to explore new biomarkers for early diagnosis and also improved therapeutic targets to overcome this issue. The implementation of microRNAs as important regulators in cancer and other pathologies expanded the possibilities of lung cancer management and not only. MiR-21 represents an intensively studied microRNA in many types of cancer, including non-small cell lung cancer (NSCLC). Its role as an oncogene is underlined in multiple studies reporting the upregulated expression of this sequence in patients diagnosed with this malignancy; moreover, several studies associated this increased expression of miR-21 with a worse outcome within NSCLC patients. The same pattern is supported by the data existent in the Cancer Genome Atlas (TCGA). The carcinogenic advantage generated by miR-21 in NSCLC resides in the target genes involved in multiple pathways such as cell growth and proliferation, angiogenesis, invasion and metastasis, but also chemo- and radioresistance. Therapeutic modulation of miR-21 by use of antisense sequences entrapped in different delivery systems has shown promising results in impairment of NSCLC. Hereby, we review the mechanisms of action of miR-21 in cancer and the associated changes upon tumor cells together a focused perspective on NSCLC signaling, prognosis and therapy.

Exosomes at a glance - common nominators for cancer hallmarks and novel diagnosis tools

Cancer represents a heterogeneous disease with multiple levels of regulation and a dynamic environment that sustains the evolution of the malignant mass. This dynamic is in part sustained by a class of extracellular vesicles termed exosomes that are able to imprint the pathological state by incorporating differential cargos in order to facilitate cell-to-cell communication. Exosomes are stable within the extracellular medium and function as shuttles secreted by healthy or pathological cells, being further taken by the accepting cell with direct effects on its phenotype. The exosomal trafficking is deeply involved in multiple levels of cancer development with roles in all cancer hallmarks. Nowadays, studies are constantly exploring the ability of exosomes to sustain the malignant progression in order to attack this pathological trafficking and impair the ability of the tumor mass to expand within the organisms. As important, the circulatory characteristics of exosomes represent a steady advantage regarding the possibility of using them as minimally invasive diagnosis tools, where cancer patients' present modified exosomal profiles compared to the healthy ones. This last characteristic, as novel diagnosis tools, has the advantage of a possible rapid transition within the clinic, compared to the studies that evaluate the therapeutic meaning.

CREB1, a direct target of miR-122, promotes cell proliferation and invasion in bladder cancer

Bladder cancer (BC) is a prevalent cancer, which arises from the epithelial lining of the urinary bladder. CAMP-response element binding protein (CREB1) acts as a transcription factor, which regulates cell transcription through phosphorylation and dephosphorylation. The purpose of this study was to explore how miR-122 worked in BC on cell proliferation and invasion. RT-qPCR was applied to evaluate the mRNA levels of CREB1 and miR-122 in BC. CCK-8 and Transwell assays were employed to determine the migratory and invasive abilities. Dual luciferase reporter assay was applied to verify miR-122 targeting CREB1 in BC. CREB1 was upregulated in bladder tissues and T24, UM-UC-3 and J82 cells, while miR-122 upregulated and had negative correlation with CREB1. Moreover, knockdown of CREB1 inhibited cell proliferative and invasive capacities. In addition, CREB1 was directly targeted by miR-122 in BC and regulated its expression. We discovered that CREB1 could reverse partially the function of miR-122 on cell proliferation and invasion. CREB1 was mediated by miR-122, and regulated cell proliferation and invasiveness. The newly identified miR-122/CREB1 axis provides novel insight into the pathogenesis of BC.

RNA interference: new mechanistic and biochemical insights with application in oral cancer therapy

Over the last few decades, the incidence of oral cancer has gradually increased, due to the negative influence of environmental factors and also abnormalities within the genome. The main issues in oral cancer treatment consist in surpassing resistance and recurrence. However, continuous discovery of altered signaling pathways in these tumors provides valuable information for the identification of novel gene candidates targeted in personalized therapy. RNA interference (RNAi) is a natural mechanism that involves small interfering RNA (siRNA); this can be exploited in biomedical research by using natural or synthetic constructs for activation of the mechanism. Synthetic siRNA transcripts were developed as a versatile class of molecular tools that have a diverse range of programmable roles, being involved in the regulation of several biological processes, thereby providing the perspective of an alternative option to classical treatment. In this review, we summarize the latest information related to the application of siRNA in oral malignancy together with molecular aspects of the technology and also the perspective upon the delivery system. Also, the emergence of newer technologies such as clustered regularly interspaced short palindromic repeats/Cas9 or transcription activator-like effector nucleases in comparison with the RNAi approach is discussed in this paper.

Diagnostic and Prognostic Potential of MicroRNA Maturation Regulators Drosha, AGO1 and AGO2 in Urothelial Carcinomas of the Bladder

Bladder cancer still requires improvements in diagnosis and prognosis, because many of the cases will recur and/or metastasize with bad outcomes. Despite ongoing research on bladder biomarkers, the clinicopathological impact and diagnostic function of miRNA maturation regulators Drosha and Argonaute proteins AGO1 and AGO2 in urothelial bladder carcinoma remain unclear. Therefore, we conducted immunohistochemical investigations of a tissue microarray composed of 112 urothelial bladder carcinomas from therapy-naïve patients who underwent radical cystectomy or transurethral resection and compared the staining signal with adjacent normal bladder tissue. The correlations of protein expression of Drosha, AGO1 and AGO2 with sex, age, tumor stage, histological grading and overall survival were evaluated in order to identify their diagnostic and prognostic potential in urothelial cancer. Our results show an upregulation of AGO1, AGO2 and Drosha in non-muscle-invasive bladder carcinomas, while there was increased protein expression of only AGO2 in muscle-invasive bladder carcinomas. Moreover, we were able to differentiate between non-muscle-invasive and muscle-invasive bladder carcinoma according to AGO1 and Drosha expression. Finally, despite Drosha being a discriminating factor that can predict the probability of overall survival in the Kaplan⁻Meier analysis, AGO1 turned out to be independent of all clinicopathological parameters according to Cox regression. In conclusion, we assumed that the miRNA processing factors have clinical relevance as potential diagnostic and prognostic tools for bladder cancer.

Bladder Cancer: New Insights into Its Molecular Pathology

Bladder cancer is one of the most prevalent cancers worldwide. Unfortunately, there have been few advances in its clinical management due to a poor understanding of the correlations between its molecular and clinical features. Mounting evidence suggests that bladder cancer comprises a group of molecularly heterogeneous diseases that undergo a variety of clinical courses and possess diverse therapeutic responses. Owing to the close association between its molecular subtypes and clinicopathological features, specific therapeutic strategies have recently been suggested. This review summarizes the current understanding of the molecular pathology of bladder cancer, including its molecular biomarkers/pathways and molecular subtypes that have been newly identified using high-throughput technologies. It also discusses advances in our understanding of personalized treatments for specific molecular subtypes.

Tumor-suppressing effects of microRNA-612 in bladder cancer cells by targeting malic enzyme 1 expression

The present study investigated the possible tumor-suppressing function of microRNA (miR)-612 and the underlying molecular mechanism of its action in bladder cancer in vitro and in vivo. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was carried out to quantify the expression levels of miR-612 in bladder cancer tissues and cell lines. The data demonstrated that the level of miR-612 expression was significantly reduced in bladder cancer tissues and cell lines, as compared with that in non-cancerous tissues and cells. Reduced miR-612 expression was associated with advanced tumor, lymph node and metastasis stages, and with distant metastasis of bladder cancer. A functional study revealed that transfection of cells with an miR-612 mimic suppressed bladder cancer cell growth, colony formation, migration, invasion and epithelial-mesenchymal transition. Bioinformatics analysis identified that miR-612 targeted the expression of malic enzyme 1 (ME1), and this was confirmed by western blot and luciferase reporter assay results. Furthermore, the ME1 expression levels were inversely associated with miR-612 expression in bladder cancer tissue specimens. In addition, knockdown of ME1 expression using ME1 siRNA mimicked the effect of ectopic miR-612 overexpression in bladder cancer cells in terms of tumor cell growth, migration and invasion. By contrast, ME1 overexpression weakened the inhibitory effect of the miR-612 mimic in bladder cancer cells. In conclusion, the present study demonstrated that miR-612 may function as a tumor suppressor in bladder cancer by targeting ME1 expression.

The Unforeseen Non-Coding RNAs in Head and Neck Cancer

Previously ignored non-coding RNAs (ncRNAs) have become the subject of many studies. However, there is an imbalance in the amount of consideration that ncRNAs are receiving. Some transcripts such as microRNAs (miRNAs) or small interfering RNAs (siRNAs) have gained much attention, but it is necessary to investigate other “pieces of the RNA puzzle”. These can offer a more complete view over normal and pathological cell behavior. The other ncRNA species are less studied, either due to their recent discovery, such as stable intronic sequence RNA (sisRNA), YRNA, miRNA-offset RNAs (moRNA), telomerase RNA component (TERC), natural antisense transcript (NAT), transcribed ultraconserved regions (T-UCR), and pseudogene transcript, or because they are still largely seen as non-coding transcripts with no relevance to pathogenesis. Moreover, some are still considered housekeeping RNAs, for instance small nucleolar RNAs (snoRNAs) and TERC. Our review summarizes the biogenesis, mechanism of action and potential role of less known ncRNAs in head and neck cancer, with a particular focus on the installment and progress for this particular cancer type.