PCA3 long noncoding RNA modulates the expression of key cancer-related genes in LNCaP prostate cancer cells

Natural products and long non-coding RNAs in prostate cancer: insights into etiology and treatment resistance

Globally, the incidence and death rates associated with cancer persist in rising, despite considerable advancements in cancer therapy. Although some malignancies are manageable by a mix of chemotherapy, surgery, radiation, and targeted therapy, most malignant tumors either exhibit poor responsiveness to early identification or endure post-treatment survival. The prognosis for prostate cancer (PCa) is unfavorable since it is a perilous and lethal malignancy. The capacity of phytochemical and nutraceutical chemicals to repress oncogenic lncRNAs and activate tumor suppressor lncRNAs has garnered significant attention as a possible strategy to diminish the development, proliferation, metastasis, and invasion of cancer cells. A potential technique to treat cancer and enhance the sensitivity of cancer cells to existing conventional therapies is the use of phytochemicals with anticancer characteristics. Functional studies indicate that lncRNAs modulate drug resistance, stemness, invasion, metastasis, angiogenesis, and proliferation via interactions with tumor suppressors and oncoproteins. Among them, numerous lncRNAs, such as HOTAIR, PlncRNA1, GAS5, MEG3, LincRNA-21, and POTEF-AS1, support the development of PCa through many molecular mechanisms, including modulation of tumor suppressors and regulation of various signal pathways like PI3K/Akt, Bax/Caspase 3, P53, MAPK cascade, and TGF-β1. Other lncRNAs, in particular, MALAT-1, CCAT2, DANCR, LncRNA-ATB, PlncRNA1, LincRNA-21, POTEF-AS1, ZEB1-AS1, SChLAP1, and H19, are key players in regulating the aforementioned processes. Natural substances have shown promising anticancer benefits against PCa by altering essential signaling pathways. The overexpression of some lncRNAs is associated with advanced TNM stage, metastasis, chemoresistance, and reduced survival. LncRNAs possess crucial clinical and transitional implications in PCa, as diagnostic and prognostic biomarkers, as well as medicinal targets. To impede the progression of PCa, it is beneficial to target aberrant long non-coding RNAs using antisense oligonucleotides or small interfering RNAs (siRNAs). This prevents them from transmitting harmful messages. In summary, several precision medicine approaches may be used to rectify dysfunctional lncRNA regulatory circuits, so improving early PCa detection and eventually facilitating the conquest of this lethal disease. Due to their presence in biological fluids and tissues, they may serve as novel biomarkers. Enhancing PCa treatments mitigates resistance to chemotherapy and radiation.

Mechanisms and progress of LncRNAs in prostate cancer development and diagnostic therapy

Prostate cancer (PCa) is a leading cause of cancer-related morbidity and mortality in men worldwide. Despite advancements in diagnosis and treatment, challenges such as late-stage detection, therapeutic resistance, and the complexity of castration-resistant prostate cancer (CRPC) persist. Long non-coding RNAs (LncRNAs) play critical roles in PCa progression through epigenetic regulation, transcriptional and post-transcriptional modulation, and immune response regulation. This review highlights the molecular mechanisms by which LncRNAs influence PCa development, treatment resistance, and immune regulation, emphasizing their potential as biomarkers and therapeutic targets. We also discuss future research directions to advance precision medicine in PCa.

Roles of Long Noncoding RNA in Prostate Cancer Pathogenesis

Prostate cancer stands as the most common cancer in men, and research into its genesis and spread is still vital. The idea that the human genome's transcriptional activity is more widespread than previously thought has received empirical validation through the application of deep sequencing-based transcriptome profiling techniques. An assortment of noncoding transcripts longer than 200 nucleotides is referred to as long noncoding RNAs (lncRNAs). Transposable elements comprise a substantial portion of the human genome, with projections indicating that their prospective proportion may reach 90%. Considering they can interact directly with proteins, alter the transcriptional activity of coding genes, and perhaps encode proteins, lncRNAs possess the capability to regulate a variety of biological processes. LncRNAs have been recognized to be key factors in the development of several types of human cancers, including lung, colorectal, and breast cancers, alongside other pathological processes that have a significant impact on the diagnosis and survival of cancer individuals. Furthermore, lncRNAs' discernible expression patterns throughout various cancer scenarios significantly raise their potential as biomarkers and therapeutic targets. We conducted an extensive analysis of the prevailing academic literature on the interaction between lncRNAs and prostate cancer in order to present a solid foundation for potential future studies on the prevention and intervention of prostate cancer. The discourse additionally expands on lncRNAs' prospective applications as targets and biomarkers for medical therapies.

Long non-coding RNAs: regulators of autophagy and potential biomarkers in therapy resistance and urological cancers

The non-coding RNAs (ncRNAs) comprise a large part of human genome that mainly do not code for proteins. Although ncRNAs were first believed to be non-functional, the more investigations highlighted tthe possibility of ncRNAs in controlling vital biological processes. The length of long non-coding RNAs (lncRNAs) exceeds 200 nucleotidesand can be present in nucleus and cytoplasm. LncRNAs do not translate to proteins and they have been implicated in the regulation of tumorigenesis. On the other hand, One way cells die is by a process called autophagy, which breaks down proteins and other components in the cytoplasm., while the aberrant activation of autophagy allegedly involved in the pathogenesis of diseases. The autophagy exerts anti-cancer activity in pre-cancerous lesions, while it has oncogenic function in advanced stages of cancers. The current overview focuses on the connection between lncRNAs and autophagy in urological cancers is discussed. Notably, one possible role for lncRNAs is as diagnostic and prognostic variablesin urological cancers. The proliferation, metastasis, apoptosis and therapy response in prostate, bladder and renal cancers are regulated by lncRNAs. The changes in autophagy levels can also influence the apoptosis, proliferation and therapy response in urological tumors. Since lncRNAs have modulatory functions, they can affect autophagy mechanism to determine progression of urological cancers.

Prostate cancer biomarkers: from early diagnosis to precision treatment

Prostate cancer (PCa) is the second most prevalent cancer in men. In 2020, approximately 1,414,259 new cases were reported that accounted for 3,75,324 deaths (Sung et al. in CA 71:209-249, 2021). PCa is often asymptomatic at early stages; hence, routine screening and monitoring based on reliable biomarkers is crucial for early detection and assessment of cancer progression. Early diagnosis of disease is key step in reducing PCa-induced mortality. Biomarkers such as PSA have played vital role in reducing recent PCa deaths. Recent research has identified many other biomarkers and also refined PSA-based tests for non-invasive diagnosis of PCa in patients. Despite progress in screening methods, an important issue that influences treatment is heterogeneity of the cancer in different individuals, necessitating personalized treatment. Currently, focus is to identify biomarkers that can accurately diagnose PCa at early stage, indicate the stage of the disease, metastatic nature and chances of survival based on individual patient profile (Fig. 1). Fig. 1 Graphical abstract.

Rho GTPase activating protein 21-mediated regulation of prostate cancer associated 3 gene in prostate cancer cell

The overexpression of the prostate cancer antigen 3 (PCA3) gene is well-defined as a marker for prostate cancer (PCa) diagnosis. Although widely used in clinical research, PCA3 molecular mechanisms remain unknown. Herein we used phage display technology to identify putative molecules that bind to the promoter region of PCA3 gene and regulate its expression. The most frequent peptide PCA3p1 (80%) was similar to the Rho GTPase activating protein 21 (ARHGAP21) and its binding affinity was confirmed using Phage Bead ELISA. We showed that ARHGAP21 silencing in LNCaP prostate cancer cells decreased PCA3 and androgen receptor (AR) transcriptional levels and increased prune homolog 2 (PRUNE2) coding gene expression, indicating effective involvement of ARHGAP21 in androgen-dependent tumor pathway. Chromatin immunoprecipitation assay confirmed the interaction between PCA3 promoter region and ARHGAP21. This is the first study that described the role of ARHGAP21 in regulating the PCA3 gene under the androgenic pathway, standing out as a new mechanism of gene regulatory control during prostatic oncogenesis.

Updated review on analysis of long non-coding RNAs as emerging diagnostic and therapeutic targets in prostate cancers

Despite advancements, prostate cancers (PCa) pose a significant global health challenge due to delayed diagnosis and therapeutic resistance. This review delves into the complex landscape of prostate cancer, with a focus on long-noncoding RNAs (lncRNAs). Also explores the influence of aberrant lncRNAs expression in progressive PCa stages, impacting traits like proliferation, invasion, metastasis and therapeutic resistance. The study elucidates how lncRNAs modulate crucial molecular effectors, including transcription factors and microRNAs, affecting signaling pathways such as androgen receptor signaling. Besides, this manuscript sheds light on novel concepts and mechanisms driving PCa progression through lncRNAs, providing a critical analysis of their impact on the disease's diverse characteristics. Besides, it discusses the potential of lncRNAs as diagnostics and therapeutic targets in PCa. Collectively, this work highlights state of art mechanistic comprehension and rigorous scientific approaches to advance our understanding of PCa and depict innovations in this evolving field of research.

Targeting long non-coding RNAs in cancer therapy using CRISPR-Cas9 technology: A novel paradigm for precision oncology

Cancer is the second leading cause of death worldwide, despite recent advances in its identification and management. To improve cancer patient diagnosis and care, it is necessary to identify new biomarkers and molecular targets. In recent years, long non-coding RNAs (lncRNAs) have surfaced as important contributors to various cellular activities, with growing proof indicating their substantial role in the genesis, development, and spread of cancer. Their unique expression profiles within specific tissues and their wide-ranging functionalities make lncRNAs excellent candidates for potential therapeutic intervention in cancer management. They are implicated in multiple hallmarks of cancer, such as uncontrolled proliferation, angiogenesis, and immune evasion. This review article explores the innovative application of CRISPR-Cas9 technology in targeting lncRNAs as a cancer therapeutic strategy. The CRISPR-Cas9 system has been widely applied in functional genomics, gene therapy, and cancer research, offering a versatile platform for lncRNA targeting. CRISPR-Cas9-mediated targeting of lncRNAs can be achieved through CRISPR interference, activation or the complete knockout of lncRNA loci. Combining CRISPR-Cas9 technology with high-throughput functional genomics makes it possible to identify lncRNAs critical for the survival of specific cancer subtypes, opening the door for tailored treatments and personalised cancer therapies. CRISPR-Cas9-mediated lncRNA targeting with other cutting-edge cancer therapies, such as immunotherapy and targeted molecular therapeutics can be used to overcome the drug resistance in cancer. The synergy of lncRNA research and CRISPR-Cas9 technology presents immense potential for individualized cancer treatment, offering renewed hope in the battle against this disease.

Long noncoding RNAs in pancreas cancer: from biomarkers to therapeutic targets

Long noncoding RNAs (lncRNAs) are noncoding RNA molecules with a heterogeneous structure consisting of 200 or more nucleotides. Because these noncoding RNAs are transcribed by RNA polymerase II, they have properties similar to messenger RNA (mRNA). Contrary to popular belief, the term "ncRNA" originated before the discovery of microRNAs. LncRNA genes are more numerous than protein-coding genes. They are the focus of current molecular research because of their pivotal roles in cancer-related processes such as cell proliferation, differentiation, and migration. The incidence of pancreatic cancer (PC) is increasing around the world and research on the molecular aspects of PC are growing. In this review, it is aimed to provide critical information about lncRNAs in PC, including the biological and oncological behaviors of lncRNAs in PC and their potential application in therapeutic strategies and as diagnostic tumor markers.

Revealing metastatic castration-resistant prostate cancer master regulator through lncRNAs-centered regulatory network

BACKGROUND

Metastatic castration-resistant prostate cancer (mCRPC) is an aggressive form of cancer unresponsive to androgen deprivation therapy (ADT) that spreads quickly to other organs. Despite reduced androgen levels after ADT, mCRPC development and lethality continues to be conducted by the androgen receptor (AR) axis. The maintenance of AR signaling in mCRPC is a result of AR alterations, androgen intratumoral production, and the action of regulatory elements, such as noncoding RNAs (ncRNAs). ncRNAs are key elements in cancer signaling, acting in tumor growth, metabolic reprogramming, and tumor progression. In prostate cancer (PCa), the ncRNAs have been reported to be associated with AR expression, PCa proliferation, and castration resistance. In this study, we aimed to reconstruct the lncRNA-centered regulatory network of mCRPC and identify the lncRNAs which act as master regulators (MRs).

METHODS

We used publicly available RNA-sequencing to infer the regulatory network of lncRNAs in mCRPC. Five gene signatures were employed to conduct the master regulator analysis. Inferred MRs were then subjected to functional enrichment and symbolic regression modeling. The latter approach was applied to identify the lncRNAs with greater predictive capacity and potential as a biomarker in mCRPC.

RESULTS

We identified 31 lncRNAs involved in cellular proliferation, tumor metabolism, and invasion-metastasis cascade. SNHG18 and HELLPAR were the highlights of our results. SNHG18 was downregulated in mCRPC and enriched to metastasis signatures. It accurately distinguished both mCRPC and primary CRPC from normal tissue and was associated with epithelial-mesenchymal transition (EMT) and cell-matrix adhesion pathways. HELLPAR consistently distinguished mCRPC from primary CRPC and normal tissue using only its expression.

CONCLUSION

Our results contribute to understanding the regulatory behavior of lncRNAs in mCRPC and indicate SNHG18 and HELLPAR as master regulators and potential new diagnostic targets in this tumor.

Emerging role of oncogenic long noncoding RNA as cancer biomarkers

The view of long noncoding RNAs as nonfunctional "garbage" has been definitely outdated by the large body of evidence indicating this class of ncRNAs as "golden junk", especially in precision oncology. Indeed, in light of their oncogenic role and the higher expression in multiple cancer types compared with paired adjacent tissues, the clinical interest for lncRNAs as diagnostic and/or prognostic biomarkers has been rapidly increasing. The emergence of large-scale sequencing technologies, their subsequent diffusion even in small research and clinical centers, the technological advances for the detection of low-copy lncRNAs in body fluids, coupled to the huge reduction of operating costs, have nowadays made possible to rapidly and comprehensively profile them in multiple tumors and large cohorts. In this review, we first summarize some relevant data about the oncogenic role of well-studied lncRNAs having a clinical relevance. Then, we focus on the description of their potential use as diagnostic/prognostic biomarkers, including an updated overview about licensed patents or clinical trials on lncRNAs in oncology.

Dysregulation of the PRUNE2/PCA3 genetic axis in human prostate cancer: from experimental discovery to validation in two independent patient cohorts

Background

We have previously shown that the long non-coding (lnc)RNA prostate cancer associated 3 (PCA3; formerly prostate cancer antigen 3) functions as a trans-dominant negative oncogene by targeting the previously unrecognized prostate cancer suppressor gene PRUNE2 (a homolog of the Drosophila prune gene), thereby forming a functional unit within a unique allelic locus in human cells. Here, we investigated the PCA3/PRUNE2 regulatory axis from early (tumorigenic) to late (biochemical recurrence) genetic events during human prostate cancer progression.

Methods

The reciprocal PCA3 and PRUNE2 gene expression relationship in paired prostate cancer and adjacent normal prostate was analyzed in two independent retrospective cohorts of clinically annotated cases post-radical prostatectomy: a single-institutional discovery cohort (n=107) and a multi-institutional validation cohort (n=497). We compared the tumor gene expression of PCA3 and PRUNE2 to their corresponding expression in the normal prostate. We also serially examined clinical/pathological variables including time to disease recurrence.

Results

We consistently observed increased expression of PCA3 and decreased expression of PRUNE2 in prostate cancer compared with the adjacent normal prostate across all tumor grades and stages. However, there was no association between the relative gene expression levels of PCA3 or PRUNE2 and time to disease recurrence, independent of tumor grades and stages.

Conclusions

We concluded that upregulation of the lncRNA PCA3 and targeted downregulation of the protein-coding PRUNE2 gene in prostate cancer could be early (rather than late) molecular events in the progression of human prostate tumorigenesis but are not associated with biochemical recurrence. Further studies of PCA3/PRUNE2 dysregulation are warranted.

Funding

We received support from the Human Tissue Repository and Tissue Analysis Shared Resource from the Department of Pathology of the University of New Mexico School of Medicine and a pilot award from the University of New Mexico Comprehensive Cancer Center. RP and WA were supported by awards from the Levy-Longenbaugh Donor-Advised Fund and the Prostate Cancer Foundation. EDN reports research fellowship support from the Brazilian National Council for Scientific and Technological Development (CNPq), Brazil, and the Associação Beneficente Alzira Denise Hertzog Silva (ABADHS), Brazil. This work has been funded in part by the NCI Cancer Center Support Grants (CCSG; P30) to the University of New Mexico Comprehensive Cancer Center (CA118100) and the Rutgers Cancer Institute of New Jersey (CA072720).

The Role of Long Non-Coding RNAs in Epithelial-Mesenchymal Transition-Related Signaling Pathways in Prostate Cancer

Prostate cancer (PCa) is one of the most common male malignancies with frequent remote invasion and metastasis, leading to high mortality. Epithelial-mesenchymal transition (EMT) is a fundamental process in embryonic development and plays a key role in tumor proliferation, invasion and metastasis. Numerous long non-coding RNAs (lncRNAs) could regulate the occurrence and development of EMT through various complex molecular mechanisms involving multiple signaling pathways in PCa. Given the importance of EMT and lncRNAs in the progression of tumor metastasis, we recapitulate the research progress of EMT-related signaling pathways regulated by lncRNAs in PCa, including AR signaling, STAT3 signaling, Wnt/β-catenin signaling, PTEN/PI3K/AKT signaling, TGF-β/Smad and NF-κB signaling pathways. Furthermore, we summarize four modes of how lncRNAs participate in the EMT process of PCa via regulating relevant signaling pathways.

The promising role of new molecular biomarkers in prostate cancer: from coding and non-coding genes to artificial intelligence approaches

Background

Risk stratification or progression in prostate cancer is performed with the support of clinical-pathological data such as the sum of the Gleason score and serum levels PSA. For several decades, methods aimed at the early detection of prostate cancer have included the determination of PSA serum levels. The aim of this systematic review is to provide an overview about recent advances in the discovery of new molecular biomarkers through transcriptomics, genomics and artificial intelligence that are expected to improve clinical management of the prostate cancer patient.

Methods

An exhaustive search was conducted by Pubmed, Google Scholar and Connected Papers using keywords relating to the genetics, genomics and artificial intelligence in prostate cancer, it includes “biomarkers”, “non-coding RNAs”, “lncRNAs”, “microRNAs”, “repetitive sequence”, “prognosis”, “prediction”, “whole-genome sequencing”, “RNA-Seq”, “transcriptome”, “machine learning”, and “deep learning”.

Results

New advances, including the search for changes in novel biomarkers such as mRNAs, microRNAs, lncRNAs, and repetitive sequences, are expected to contribute to an earlier and accurate diagnosis for each patient in the context of precision medicine, thus improving the prognosis and quality of life of patients. We analyze several aspects that are relevant for prostate cancer including its new molecular markers associated with diagnosis, prognosis, and prediction to therapy and how bioinformatic approaches such as machine learning and deep learning can contribute to clinic. Furthermore, we also include current techniques that will allow an earlier diagnosis, such as Spatial Transcriptomics, Exome Sequencing, and Whole-Genome Sequencing.

Conclusion

Transcriptomic and genomic analysis have contributed to generate knowledge in the field of prostate carcinogenesis, new information about coding and non-coding genes as biomarkers has emerged. Synergies created by the implementation of artificial intelligence to analyze and understand sequencing data have allowed the development of clinical strategies that facilitate decision-making and improve personalized management in prostate cancer.

Effective Diagnosis of Prostate Cancer Based on mRNAs From Urinary Exosomes

Background

Novel non-invasive biomarkers are urgently required to improve the diagnostic sensitivity and specificity of prostate cancer (PCa). Therefore, the diagnostic value of following candidate genes (ERG, PCA3, ARV7, PSMA, CK19, and EpCAM) were estimated by testing mRNAs from urinary exosomes of patients with primary PCa.

Methods

Exosomes were obtained using size-exclusion chromatography (SEC), out of which RNAs were extracted, then analyzed by quantitative reverse transcription-polymerase chain reaction according to manufacturer's protocol.

Results

The expression of urinary exosomal ERG, PCA3, PSMA, CK19, and EpCAM were significantly increased in patients with PCa compared with healthy males. In addition, the levels of urinary exosomal ERG, ARV7, and PSMA were intimately correlated with the Gleason score in PCa patients (P < 0.05). The receiver operating characteristic curves (ROCs) showed that urinary exosomal ERG, PCA3, PSMA, CK19, and EpCAM were able to distinguish patients with PCa from healthy individuals with the area under the curve (AUC) of 0.782, 0.783, 0.772, 0.731, and 0.739, respectively. Urinary exosomal PCA3 and PSMA distinguished PCa patients from healthy individuals with an AUC of 0.870. Combination of urinary exosomal PCA3, PSMA with serum PSA and PI-RADS achieved higher AUC compared with PSA alone (0.914 and 0.846, respectively). Kaplan-Meier curves demonstrated that PCA3, ARV7, and EpCAM were associated in androgen-deprivation therapy (ADT) failure time which is defined as from the initiation of ADT in hormone-sensitive stage to the development of castration-resistant prostate cancer.

Conclusion

These findings suggested that mRNAs from urinary exosomes have the potential in serving as novel and non-invasive indicators for PCa diagnosis and prediction.

Molecular and cellular functions of long non-coding RNAs in prostate and breast cancer

Long noncoding RNAs (lncRNAs) are defined as noncoding RNA transcripts with a length greater than 200 nucleotides. Research over the last decade has made great strides in our understanding of lncRNAs, especially in the biology of their role in cancer. In this article, we will briefly discuss the biogenesis and characteristics of lncRNAs, then review their molecular and cellular functions in cancer by using prostate and breast cancer as examples. LncRNAs are abundant, diverse, and evolutionarily, less conserved than protein-coding genes. They are often expressed in a tumor and cell-specific manner. As a key epigenetic factor, lncRNAs can use a wide variety of molecular mechanisms to regulate gene expression at each step of the genetic information flow pathway. LncRNAs display widespread effects on cell behavior, tumor growth, and metastasis. They act intracellularly and extracellularly in an autocrine, paracrine and endocrine fashion. Increased understanding of lncRNA's role in cancer has facilitated the development of novel biomarkers for cancer diagnosis, led to greater understanding of cancer prognosis, enabled better prediction of therapeutic responses, and promoted identification of potential targets for cancer therapy.

Diagnostic, prognostic and therapeutic potential of long noncoding RNAs in cancer

Long noncoding RNAs (lncRNAs) are longer than 200 nucleotides in length and undergo splicing, capping, polyadenylation, and editing just like mRNA. Evidence is growing that they regulate transcription, splicing, RNA degradation, and translation of genes and that their expression has been linked to a variety of illnesses, including cancer. The advancement of next-generation and high-throughput sequencing has changed the way lncRNAs are identified and characterized, revealing a relationship between lncRNAs and several tumor types. Since then, they have gained a significant attraction as a promising candidate in cancer diagnosis, prognosis, and therapy. Furthermore, they are a good candidate for consideration as tumor biomarkers due to their high stability, better tissue/cell selectivity, aberrant expression in certain malignancies, and easy and noninvasive detection. In addition, lncRNAs are being examined as therapeutic targets in clinical trials for a variety of malignancies. This review highlights the potential of lncRNAs as biomarkers or therapeutic targets in light of the current progress, clinical investigations, and patents filed so far.

RNA-based biomarkers for the diagnosis, prognosis, and therapeutic response monitoring of prostate cancer

Prostate cancer (CaP) is the most common malignant neoplasm of the urinary tract. The current recommendations for CaP diagnosis rely on the prostate-specific antigen levels and a digital rectal examination for anatomical abnormalities. However, these diagnostic tools are not highly sensitive. In particular, prostate-specific antigen has a low positive predictive value (approximately 30%). Thus, there is a need to develop biomarkers to improve the early clinical detection of CaP. Several novel technologies enable the identification of biomarkers from diverse sources, including the urine, serum, and prostate tissues. Furthermore, advances in genomic techniques have enabled the analysis of novel biomarkers, such as deoxyribonucleic acids (DNAs), ribonucleic acids (RNAs), proteins, and circulating tumor cells. Previous studies have demonstrated that RNAs are potential diagnostic biomarkers for various cancers using high-throughput sequencing analysis. The sensitivity and specificity of RNA biomarkers are higher than those of protein biomarkers. Polymerase chain reaction enables the amplification of trace levels of RNAs with high sensitivity and specificity. RNA biomarkers provide dynamic insights into cellular states and regulatory processes when compared with DNA biomarkers. Additionally, multiple copies of various RNAs in a cell provide more information than DNA. The levels of specific RNAs in CaP tissues are upregulated when compared with those in non-cancerous tissues. Additionally, RNAs can be easily isolated from various body fluids. Thus, RNAs are potential non-invasive biomarkers for CaP. Moreover, the analysis of RNA levels adjusted for each stage of CaP enables the determination of prognostic individualized therapy for aggressive or progressive CaP. This review focused on the diagnostic and prognostic values of RNAs for CaP.

Interaction between Non-Coding RNAs and Androgen Receptor with an Especial Focus on Prostate Cancer

The androgen receptor (AR) is a member of the nuclear receptor superfamily and has three functional domains, namely the N-terminal, DNA binding, and C-terminal domain. The N-terminal domain harbors potent transactivation functions, whereas the C-terminal domain binds to androgens and antiandrogens used to treat prostate cancer. AR has genomic activity being DNA binding-dependent or through interaction with other DNA-bound transcription factors, as well as a number of non-genomic, non-canonical functions, such as the activation of the ERK, AKT, and MAPK pathways. A bulk of evidence indicates that non-coding RNAs have functional interactions with AR. This type of interaction is implicated in the pathogenesis of human malignancies, particularly prostate cancer. In the current review, we summarize the available data on the role of microRNAs, long non-coding RNAs, and circular RNAs on the expression of AR and modulation of AR signaling, as well as the effects of AR on their expression. Recognition of the complicated interaction between non-coding RNAs and AR has practical importance in the design of novel treatment options, as well as modulation of response to conventional therapeutics.

Prognostic Value of LncRNA KRT18P55 in Patients with Intestinal Type of Gastric Cancer

PURPOSE

Gastric cancer (GC) is a heterogeneous disease, and this heterogeneity significantly affects survival and treatment outcomes. Identification of molecular biomarkers specific for early-stage GC can help clinicians to choose more precise and effective treatment approaches. Long non-coding RNAs (lncRNAs) have the potential to be used as biomarkers because of their tissue specificity, stability, and availability in body fluids. In this study, we aimed to investigate changes in the expression levels of lncRNA KRT18P55 and to assess its biomarker potentials in patients with GC.

METHODS

Tumor and non-tumor marginal tissues were collected from 102 patients at Noor-Nejat Hospital (Tabriz, Iran). RNA was isolated, and quantitative reverse transcriptase PCR (qRT-PCR) was performed to assess KRT18P55 expression levels in tumor and non-tumor tissue samples. The receiver operating characteristic (ROC) curve analysis was performed to evaluate potentials of KRT18P55 as a prognostic biomarker in GC. SPSS and GraphPad Prism software were used for data analysis.

RESULTS

We found that KRT18P55 is significantly overexpressed in tumor as compared to non-tumor tissues (p < 0.0001). We found a significant association between KRT18P55 overexpression and intestinal GC subtype (p < 0.0001), lymph node metastasis (p = 0.013), and Helicobacter pylori infection (p = 0.033). Based on the ROC analysis, KRT18P55 showed a sensitivity and specificity of 53.92% and 77.45%, respectively.

CONCLUSION

Overexpression of KRT18P55 in gastric tumors is suggestive of its oncogenic role in GC. In addition, KRT18P55 may be used as a potential prognosis biomarker and therapeutic target in intestinal GC subtype.

Transcriptional landscape of PTEN loss in primary prostate cancer

BACKGROUND

PTEN is the most frequently lost tumor suppressor in primary prostate cancer (PCa) and its loss is associated with aggressive disease. However, the transcriptional changes associated with PTEN loss in PCa have not been described in detail. In this study, we highlight the transcriptional changes associated with PTEN loss in PCa.

METHODS

Using a meta-analysis approach, we leveraged two large PCa cohorts with experimentally validated PTEN and ERG status by Immunohistochemistry (IHC), to derive a transcriptomic signature of PTEN loss, while also accounting for potential confounders due to ERG rearrangements. This signature was expanded to lncRNAs using the TCGA quantifications from the FC-R2 expression atlas.

RESULTS

The signatures indicate a strong activation of both innate and adaptive immune systems upon PTEN loss, as well as an expected activation of cell-cycle genes. Moreover, we made use of our recently developed FC-R2 expression atlas to expand this signature to include many non-coding RNAs recently annotated by the FANTOM consortium. Highlighting potential novel lncRNAs associated with PTEN loss and PCa progression.

CONCLUSION

We created a PCa specific signature of the transcriptional landscape of PTEN loss that comprises both the coding and an extensive non-coding counterpart, highlighting potential new players in PCa progression. We also show that contrary to what is observed in other cancers, PTEN loss in PCa leads to increased activation of the immune system. These findings can help the development of new biomarkers and help guide therapy choices.

Current Trends in Prevalence and Role of Long Noncoding RNA and Gene Fusion in Prostate Cancer: An Overview

Objectives The aim of this study is to analyze the current scenario in the diagnostic modalities for prostate cancer.

Materials and Methods We searched PubMed, Google Scholar, and ResearchGate for relevant data. Articles published in the last 10 years were taken into consideration. The role of long noncoding RNA and gene fusion products in the context of prostate cancer was reviewed, which included their roles in diagnosis, prognosis, and assessment of response to therapy.

Results Several long noncoding RNAs (lncRNA) have been isolated and have been shown to be useful in diagnosing and prognosticating prostate cancer. We have also looked into the role of TMPRSS2:ERG gene fusion in prostate carcinoma diagnosis. These molecular parameters have been looked into due to the fact that the current parameters in use such as prostate-specific antigen have several drawbacks that limit their potential.

Effects of long non-coding RNAs on androgen signaling pathways in genitourinary malignancies

The non-coding RNA (ncRNA) are generally classified, based on length, into small ncRNAs less than 200 nucleotides, such as miRNA, and long ncRNA (lnRNA) with more than 200 nucleotides. The transcription of ncRNAs, similarly to genes that code for proteins, is highly deregulated in cancer. Their expression level can influence physiological processes, e.g. epigenetic regulation of gene expression, regulation of cell cycle and modification of chromatin. Recent studies on androgen receptor in oncology revealed that it exerts a pivotal role in genitourinary malignancies, in particular in prostate tumor was demonstrated that its deregulation takes part in all stages of carcinogenesis. Here, we discuss present learning of the main lnRNAs involvement on androgen signaling pathways in genitourinary neoplasms, highlighting lnRNAs potential in the regulating network comfortable to cancer onset and progression, and discuss the lnRNAs prognostic and diagnostic value in cancer management.

Urinary Biomarkers in Tumors: An Overview

Recent reports suggest that urine is a useful noninvasive tool for the identification of urogenital tumors, including bladder, prostate, kidney, and other nonurological cancers. As a liquid biopsy, urine represents an important source for the improvement of new promising biomarkers, a suitable tool to identify indolent cancer and avoid overtreatment. Urine is enriched with DNAs, RNAs, proteins, circulating tumor cells, exosomes, and other small molecules which can be detected with several diagnostic methodologies.We provide an overview of the ongoing state of urinary biomarkers underlying both their potential utilities to improve cancer prognosis, diagnosis, and therapeutic strategy and their limitations.

PCA3 controls chromatin organization and p53 signal activation by regulating LAP2α-lamin A complexes

Prostate cancer antigen 3 (PCA3) is a prostate cancer-specific long noncoding RNA (lncRNA). Here, we report that lncRNA PCA3 plays a role in prostate cancer progression that is mediated by nucleoplasmic lamins. PCA3 interacts with the C-terminal region of lamina-associated polypeptide (LAP) 2α. The C-terminal region of LAP2α includes tumor suppressor protein retinoblastoma (pRb)- and lamin-binding domains, and it is necessary for the regulation and stabilization of the nucleoplasmic pool of lamin A. PCA3 inhibits the interaction of LAP2α with lamin A through binding with the C-terminus of LAP2α. The level of nucleoplasmic lamin A/C is increased by knockdown of PCA3. Together, the level of LAP2α within the nucleus is increased by PCA3 knockdown. In PCA3 knockdown cells, the levels of HP1γ, trimethylation of Lys9 on histone H3 (H3K9me3), and trimethylation of Lys36 on histone H3 (H3K36me3)　are upregulated. In contrast, trimethylation of Lys4 on histone H3 (H3K4me3) is downregulated. We further demonstrate that activation of the p53 signaling pathway and cell cycle arrest are promoted in the absence of PCA3. These findings support a unique mechanism in which prostate cancer-specific lncRNA controls chromatin organization via regulation of the nucleoplasmic pool of lamins. This proposed mechanism suggests that cancer progression may be mediated by nuclear lamins.

Long Noncoding RNAs as Innovative Urinary Diagnostic Biomarkers

The characterization of circulating tumor cells (CTCs) is now widely studied as a promising source of cancer-derived biomarkers because of their role in tumor formation and progression. However, CTCs analysis presents some limitations and no standardized method for CTCs isolation from urine has been defined so far. In fact, besides blood, urine represents an ideal source of noninvasive biomarkers, especially for the early detection of genitourinary tumors. Besides CTCs, long noncoding RNAs (lncRNAs) have also been proposed as potential noninvasive biomarkers, and the evaluation of the diagnostic accuracy of urinary lncRNAs has dramatically increased over the last years, with many studies being published. Therefore, this review provides an update on the clinical utility of urinary lncRNAs as novel biomarkers for the diagnosis of bladder and prostate cancers.

Non-Coding RNAs Set a New Phenotypic Frontier in Prostate Cancer Metastasis and Resistance

Prostate cancer (PCa) mortality remains a significant public health problem, as advanced disease has poor survivability due to the development of resistance in response to both standard and novel therapeutic interventions. Therapeutic resistance is a multifaceted problem involving the interplay of a number of biological mechanisms including genetic, signaling, and phenotypic alterations, compounded by the contributions of a tumor microenvironment that supports tumor growth, invasiveness, and metastasis. The androgen receptor (AR) is a primary regulator of prostate cell growth, response and maintenance, and the target of most standard PCa therapies designed to inhibit AR from interacting with androgens, its native ligands. As such, AR remains the main driver of therapeutic response in patients with metastatic castration-resistant prostate cancer (mCRPC). While androgen deprivation therapy (ADT), in combination with microtubule-targeting taxane chemotherapy, offers survival benefits in patients with mCRPC, therapeutic resistance invariably develops, leading to lethal disease. Understanding the mechanisms underlying resistance is critical to improving therapeutic outcomes and also to the development of biomarker signatures of predictive value. The interconversions between epithelial-to-mesenchymal transition (EMT) and mesenchymal-to-epithelial transition (MET) navigate the prostate tumor therapeutic response, and provide a novel targeting platform in overcoming therapeutic resistance. Both microRNA (miRNA)- and long non-coding RNA (lncRNA)-mediated mechanisms have been associated with epigenetic changes in prostate cancer. This review discusses the current evidence-based knowledge of the role of the phenotypic transitions and novel molecular determinants (non-coding RNAs) as contributors to the emergence of therapeutic resistance and metastasis and their integrated predictive value in prostate cancer progression to advanced disease.

Unraveling the dark matter, long non-coding RNAs, in male reproductive diseases: A narrative review

Recent advances in human transcriptome have revealed the fundamental and functional roles of long non-coding RNA in the susceptibility to diverse diseases and pathological conditions. They participate in wide range of biological processes such as the modulating of chromatin structure, transcription, translation, and post-translation modification. In addition, based on their unique expression profiles and their association with clinical abnormalities such as those of related to male reproductive diseases, they can be used to develop therapeutic methods and biomarkers for screening of the diseases. In this study, we will review the identified lncRNAs and their molecular functions in the pathogenesis of male reproductive diseases such as prostate cancer, benign prostatic hyperplasia, prostatitis, testicular cancer, varicocele, and sperm abnormalities.

Long Non-coding RNAs in Cancer: Implications for Diagnosis, Prognosis, and Therapy

Long non-coding RNAs (lncRNAs) are major components of cellular transcripts that are arising as important players in various biological pathways. They have received extensive attention in recent years, regarded to be involved in both developmental processes and various diseases. Due to their specific expression and functional diversity in a variety of cancers, lncRNAs have promising applications in cancer diagnosis, prognosis and therapy. Studies have shown that lncRNAs with high specificity and accuracy have the potential to become biomarkers in cancers. LncRNAs can be noninvasively extracted from body fluids, tissues and cells, and can be used as independent or auxiliary biomarkers to improve the accuracy of diagnosis or prognosis. Currently, the most well-recognized lncRNA is PCA3, which has been approved for use in the diagnosis of prostate cancer. Moreover, the underlying mechanisms of lncRNAs were explored as therapeutic targets, which have been investigated in clinical trials of several cancers. In this review, we presented a compilation of recent publications, clinical trials and patents, addressing the potential of lncRNAs that could be considered as biomarkers or therapeutic targets, with the hopes of providing promised implications for future cancer therapy.

Prostatic aspirated cellular RNA analysis enables fast diagnosis and staging of prostate cancer

•

Aspirated cellular RNA analysis technique based on needle biopsies was firstly described on prostate cancer (PCa).

•

Aspirated cellular RNA analysis can provide urgent information for PCa diagnosis and staging.

•

This technique enables fast and reliable review of whole-biopsy molecular profile prior to histopathological diagnosis.

Objective

The aim of this study is to investigate the potential application of prostatic aspirated cellular RNA analysis technique for fast diagnosing and staging prostate cancer.

Methods

Prostatic aspirated cells were obtained immediately after transrectal ultrasound (TRUS)-guided needle biopsy. Cellular RNA such as glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA, prostate specific antigen (PSA) mRNA and prostate-specific RNA (PCA3) mRNA were analyzed by using Reverse Transcription-Polymerase Chain Reaction (RT-PCR). PCA3 score was calculated as the ratio of PCA3 mRNA to PSA mRNA expression. Diagnostic performance of the fast-aspirated cellular RNA analysis technique for determining prostate cancer and metastatic status were evaluated by developing receiver operating characteristic curves (ROC), and the correlation between aspirated cellular RNA mRNA expressions and risk grouping was calculated, to investigate the underlying potential for PCa staging.

Results

PCA3 score was significantly higher in prostatic aspirated cells obtained from cancerous tissues than noncancerous tissues. The median aspirated cellular PCA3 score was higher in patients with PCa compared to BPH, and presenting an area under the ROC curve (AUC) of 0.87 (95%CI: 0.79–0.94) for PCa diagnosis. Multivariate regression analysis revealed that baseline median aspirated cellular PCA3 score (OR=9.316, 95%CI: 1.045–83.033, P<0.05) was an independent predictive factor for metastatic status in PCa patients.

Conclusion

The ease of use and minimal complexity of fast prostatic aspirated cellular RNA analysis may be a valuable diagnostic technique, providing urgent diagnostic information for accurate PCa diagnosing and staging.

OncoMX: A Knowledgebase for Exploring Cancer Biomarkers in the Context of Related Cancer and Healthy Data

PURPOSE

The purpose of OncoMX¹ knowledgebase development was to integrate cancer biomarker and relevant data types into a meta-portal, enabling the research of cancer biomarkers side by side with other pertinent multidimensional data types.

METHODS

Cancer mutation, cancer differential expression, cancer expression specificity, healthy gene expression from human and mouse, literature mining for cancer mutation and cancer expression, and biomarker data were integrated, unified by relevant biomedical ontologies, and subjected to rule-based automated quality control before ingestion into the database.

RESULTS

OncoMX provides integrated data encompassing more than 1,000 unique biomarker entries (939 from the Early Detection Research Network [EDRN] and 96 from the US Food and Drug Administration) mapped to 20,576 genes that have either mutation or differential expression in cancer. Sentences reporting mutation or differential expression in cancer were extracted from more than 40,000 publications, and healthy gene expression data with samples mapped to organs are available for both human genes and their mouse orthologs.

CONCLUSION

OncoMX has prioritized user feedback as a means of guiding development priorities. By mapping to and integrating data from several cancer genomics resources, it is hoped that OncoMX will foster a dynamic engagement between bioinformaticians and cancer biomarker researchers. This engagement should culminate in a community resource that substantially improves the ability and efficiency of exploring cancer biomarker data and related multidimensional data.

Long non-coding RNAs in prostate tumorigenesis and therapy (Review)

Prostate cancer (PCa) is one of the most frequently diagnosed malignancy. Although there have been many advances in PCa diagnosis and therapy, the concrete mechanism remains unknown. Long non-coding RNAs (lncRNAs) are novel biomarkers associated with PCa, and their dysregulated expression is closely associated with risk stratification, diagnosis and carcinogenesis. Accumulating evidence has suggested that lncRNAs play important roles in prostate tumorigenesis through relevant pathways, such as androgen receptor interaction and PI3K/Akt. The present review systematically summarized the potential clinical utility of lncRNAs and provided a novel guide for their function in PCa.

Effect of upregulation of DD3 on early detection and prognosis in prostate cancer

Background

Expression of prostate cancer antigen 3 (PCA3 OR DD3) in the blood has been reported to be significantly higher in prostate cancer (PCa) than in benign prostate hyperplasia (BPH). To confirm whether DD3 expression is significantly different between PCa and BPH tissues, DD3 expression was tested in the blood both preoperatively and postoperatively and in the paired tissues of PCa patients.

Methods

Expression levels of DD3 mRNA in the blood of patients who did not undergo surgery (PCa, n=102; BPH, n=53), those underwent surgery (preoperative, n=35; postoperative, n=35), and in PCa tissue specimens (tumor, n=41; adjacent normal, n=21) were determined by real-time quantitative PCR. Sensitivity and specificity for DD3 in PCa patients were validated by receiver operating characteristic (ROC) curve analysis.

Results

Our data suggest that expression level of DD3 in blood samples was significantly higher in PCa patients than in BPH patients (P=0.005). Expression of DD3 mRNA was also significantly elevated in PCa tissues compared with adjacent normal tissues (P=0.013). The increase in DD3 expression in PCa patients was further validated using a dataset from The Cancer Genome Atlas (n=549). Postoperative DD3 expression decreased following surgical intervention (P<0.001). Moreover, low DD3 expression was associated with improved overall survival (OS). Using gene set enrichment analysis, DD3 expression was correlated with specific PCa target genes including carcinogenesis-related and cancer proliferation-related genes.

Conclusions

This study demonstrated that expression of DD3 was upregulated in blood and PCa tumor tissues and was associated with prognosis. The oncogenic role of DD3 was further validated in the TCGA database, indicating that DD3 is a potential therapeutic target for PCa. Furthermore, this study suggests that DD3 expression could be considered as a prognostic biomarker for PCa.

Long non-coding RNA LINC01419 mediates miR-519a-3p/PDRG1 axis to promote cell progression in osteosarcoma

Background

Osteosarcoma (OS) is one of the most aggressive malignancies with mortality rate worldwide. Accumulating evidence has revealed that long noncoding RNAs (lncRNAs) exert important functions in regulation of cancer initiation and progression. Recently, long intergenic non-protein coding RNA 1419 (LINC01419) has been reported to function as an oncogene in several cancers. However, its role in OS has not been explored yet.

Methods

qRT-PCR and western blot analyses were implemented to determine the expression of genes. The function of OS cells was assessed through colony formation, EdU, JC-1, TUNEL, transwell, and immunofluorescence (IF) assays. FISH and subcellular fractionation assays were conducted to estimate the localization of LINC01419 in OS cells. The interaction between genes was validated through luciferase reporter and RNA pull down assays.

Results

LINC01419 expression was elevated in OS tissues and cells. Functionally, LINC01419 accelerated OS cell proliferation, motility and EMT. In vivo assay showed that silencing LINC01419 hindered the growth of OS tumors. Mechanistic investigation unveiled that LINC01419 acted as a competing endogenous RNA (ceRNA) to augment PDRG1 expression by miR-519a-3p sequestration. Rescue assays verified the oncogenic effect of LINC01419/miR-519a-3p/PDRG1 axis on OS development.

Conclusion

LINC01419 mediates malignant phenotypes in OS by targeting miR-519a-3p/PDRG1 axis.

Urinary PCA3 detection in prostate cancer by magnetic nanoparticles coupled with colorimetric enzyme-linked oligonucleotide assay

PCA3 is one of the most prostate cancer-specific genes described to date. Of note, PCA3 expression is detectable at high level in the urine of prostate cancer (PCa) patients. Accordingly, PCA3 is an ideal biomarker for PCa diagnosis. Several techniques for the measurement of this biomarker in urine have been developed but there are still some drawbacks. In this study, magnetic nanoparticle-based PCR coupled with streptavidin-horseradish peroxidase and a substrate for colorimetric detection was established as a potential assay for urinary PCA3 detection. The method provided a high specificity for PCA3 gene in LNCaP prostate cancer cell line. Additionally, this technique could detect PCA3 at femtogram level which was approximately 1,000-fold more sensitive than the conventional RT-PCR followed by agarose gel electrophoresis. The effectiveness of the method was assessed by PCA3 detection in clinical specimens. The relative PCA3 expression of PCa patients determined by this assay was significantly greater than that of benign prostatic hyperplasia (BPH) patients and healthy controls. The results of our test were comparable with the results of qRT-PCR. The proposed method is promising to distinguish between cancerous and non-cancerous groups. Altogether, this simple assay is practicable and useful for prostate cancer diagnosis.

Long non-coding RNAs in genitourinary malignancies: a whole new world

Long non-coding RNAs (lncRNAs) are regulators of cellular machinery that are commonly dysregulated in genitourinary malignancies. Accordingly, the investigation of lncRNAs is improving our understanding of genitourinary cancers, from development to progression and dissemination. lncRNAs are involved in major oncogenic events in genitourinary malignancies, including androgen receptor (AR) signalling in prostate cancer, hypoxia-inducible factor (HIF) pathway activation in renal cell carcinoma and invasiveness in bladder cancer, as well as multiple other proliferation and survival mechanisms. In line with their putative oncogenic roles, new lncRNA-based classifications are emerging as potent predictors of prognosis. In clinical practice, detection of oncogenic lncRNAs in serum or urine might enable early cancer detection, and lncRNAs might also be promising therapeutic targets for patients with genitourinary cancer. Furthermore, as predictors of sensitivity to anticancer treatments, lncRNAs could be integrated into future precision medicine strategies. Overall, lncRNAs are promising new candidates for molecular studies and for discovery of innovative biomarkers and are putative therapeutic targets in genitourinary oncology.

The long non-coding RNA PCA3: an update of its functions and clinical applications as a biomarker in prostate cancer

Prostate cancer antigen 3 (PCA3) is an overexpressed prostate long non-coding RNA (lncRNA), transcribed from an intronic region at the long arm of human chromosome 9q21–22. It has been described that PCA3 modulates prostate cancer (PCa) cell survival through modulating androgen receptor (AR) signaling, besides controlling the expression of several androgen responsive and cancer-related genes, including epithelial–mesenchymal transition (EMT) markers and those regulating gene expression and cell signaling. Also, PCA3 urine levels have been successfully used as a PCa diagnostic biomarker. In this review, we have highlighted recent findings regarding PCA3, addressing its gene structure, putative applications as a biomarker, a proposed origin of this lncRNA, roles in PCa biology and expression patterns. We also updated data regarding PCA3 interactions with cancer-related miRNAs and expression in other tissues and diseases beyond the prostate. Altogether, literature data indicate aberrant expression and dysregulated activity of PCA3, suggesting PCA3 as a promising relevant target that should be even further evaluated on its applicability for PCa detection and management.

Long non-coding RNAs in prostate cancer: Functional roles and clinical implications

Long noncoding RNAs (lncRNAs) are defined as RNA transcripts longer than 200 nucleotides that do not encode proteins. LncRNAs have been documented to exhibit aberrant expression in various types of cancer, including prostate cancer. Currently, screening for prostate cancer results in overdiagnosis. The consequent overtreatment of patients with indolent disease in the clinic is due to the lack of appropriately sensitive and specific biomarkers. Thus, the identification of lncRNAs as novel biomarkers and therapeutic targets for prostate cancer is promising. In the present review, we attempt to summarize the current knowledge of lncRNA expression patterns and mechanisms in prostate cancer. In particular, we focus on lncRNAs regulated by the androgen receptor and the specific molecular mechanism of lncRNAs in prostate cancer to provide a potential clinical therapeutic strategy for prostate cancer.

The evolution of long noncoding RNA acceptance in prostate cancer initiation, progression, and its clinical utility in disease management

CONTEXT

It is increasingly evident that non-protein-coding regions of the genome can give rise to transcripts that form functional layers of the cancer genome. One of most abundant classes in these regions is long noncoding RNAs (lncRNAs). They have gained increasing attention in prostate cancer (PCa) and paved the way for a greater understanding of these cryptic regulators in cancer.

OBJECTIVE

To review current research exploring the functional biology of lncRNAs in PCa over the past three decades.

EVIDENCE ACQUISITION

A systematic review was performed using PubMed to search for reports with terms "long noncoding RNA", "prostate", and "cancer" over the past 30 yr (1988-2018).

EVIDENCE SYNTHESIS

We comprehensively surveyed the literature collected and summarise experiments leading to the characterisation of lncRNAs in PCa. A historical timeline of lncRNA identification is described, where each lncRNA is categorised mechanistically and within the primary areas of carcinogenesis: tumour risk and initiation, tumour promotion, tumour suppression, and tumour treatment resistance. We describe select lncRNAs that exemplify these areas. We also review whether these lncRNAs have a clinical utility in PCa diagnosis, prognosis, and prediction, and as therapeutic targets.

CONCLUSIONS

The biology of lncRNA is multifaceted, demonstrating a complex array of molecular and cellular functions. These studies reveal that lncRNAs are involved in every stage of PCa. Their clinical utility for diagnosis, prognosis, and prediction of PCa is well supported, but further evaluation for their therapeutic candidacy is needed. We provide a detailed resource and view inside the lncRNA landscape for other cancer biologists, oncologists, and clinicians.

PATIENT SUMMARY

In this study, we review current knowledge of the non-protein-coding genome in prostate cancer (PCa). We conclude that many of these regions are functional and a source of accurate biomarkers in PCa. With a strong research foundation, they hold promise as future therapeutic targets, yet clinical trials are necessary to determine their intrinsic value to PCa disease management.

Competing Endogenous RNA and Coexpression Network Analysis for Identification of Potential Biomarkers and Therapeutics in association with Metastasis Risk and Progression of Prostate Cancer

Prostate cancer (PCa) is the most frequently diagnosed malignant neoplasm in men. Despite the high incidence, the underlying pathogenic mechanisms of PCa are still largely unknown, which limits the therapeutic options and leads to poor prognosis. Herein, based on the expression profiles from The Cancer Genome Atlas (TCGA) database, we investigated the interactions between long noncoding RNA (lncRNA) and mRNA by constructing a competing endogenous RNA network. Several competing endogenous RNAs could participate in the tumorigenesis of PCa. Six lncRNA signatures were identified as potential candidates associated with stage progression by the Kolmogorov-Smirnov test. In addition, 32 signatures from the coexpression network had potential diagnostic value for PCa lymphatic metastasis using machine learning algorithms. By targeting the coexpression network, the antifungal compound econazole was screened out for PCa treatment. Econazole could induce growth restraint, arrest the cell cycle, lead to apoptosis, inhibit migration, invasion, and adhesion in PC3 and DU145 cell lines, and inhibit the growth of prostate xenografts in nude mice. This systematic characterization of lncRNAs, microRNAs, and mRNAs in the risk of metastasis and progression of PCa will aid in the identification of candidate prognostic biomarkers and potential therapeutic drugs.

Discovery of a novel long noncoding RNA overlapping the LCK gene that regulates prostate cancer cell growth

Background

Virtually all patients with metastatic prostate cancer (PCa) will relapse and develop lethal castration-resistant prostate cancer (CRPC). Long noncoding RNAs (lncRNAs) are emerging as critical regulatory elements of many cellular biological processes, and may serve as therapeutic targets for combating PCa progression. Here, we have discovered in a high-throughput RNAi screen a novel lncRNA in PCa, and assessed the oncogenic effects of this lncRNA.

Methods

Rapid amplification of cDNA ends and sequencing was utilized to identify a previously unannotated lncRNA lying within exon six and the 3’UTR of the lymphocyte-specific protein tyrosine kinase (LCK) gene. The levels of HULLK in the presence or absence of hormone and/or enzalutamide or coregulator inhibitors were measured by quantitative PCR (qPCR). The determination of HULLK transcription and localization were characterized by strand-specific qPCR and cellular fractionation followed by qPCR, respectively. The correlation between HULLK expression and prostate cancer Gleason score was analyzed by droplet digital PCR. CyQuant assays were conducted to evaluate the effects of knocking down HULLK with shRNAs or overexpressing HULLK on cell growth.

Results

In this study, a previously unannotated lncRNA lying within exon six and 3’UTR of the LCK gene was dramatically upregulated by androgen in a dose-dependent manner, and the anti-androgen enzalutamide completely blocked this hormone-induced increase. Therefore, we labeled this lncRNA “HULLK” for Hormone-Upregulated lncRNA within LCK. Binding sites for two AR coregulators p300 and Brd4 reside near the HULLK transcriptional start site (TSS), and inhibitors of these coregulators downregulated HULLK. HULLK is transcribed from the sense strand of DNA, and predominantly localizes to the cytoplasm. HULLK transcripts are not only expressed in prostate cancer cell lines, but also prostate cancer patient tissue. Remarkably, there was a significant positive correlation between HULLK expression and high-grade PCa in multiple cohorts. shRNAs targeting HULLK significantly decreased PCa cell growth. Moreover, cells overexpressing HULLK were hypersensitive to androgen stimulation.

Conclusions

HULLK is a novel lncRNA situated within the LCK gene that may serve as an oncogene in PCa. Our data enhances our understanding of lncRNA biology and may assist in the development of additional biomarkers or more effective therapeutic targets for advanced PCa.

Electronic supplementary material

The online version of this article (10.1186/s12943-019-1039-6) contains supplementary material, which is available to authorized users.

RNA-based markers in biopsy cores with atypical small acinar proliferation: Predictive effect of T2E fusion positivity and MMP-2 upregulation for a subsequent prostate cancer diagnosis

BACKGROUND

Atypical small acinar proliferation (ASAP) is a precursor lesion of prostate cancer (PC), and PC develops from this suspicious focus or an unsampled malignant gland nearby. However, PC-related molecular alterations that could guide the timing of repeat biopsies and help monitor PC risk in ASAP-diagnosed patients have not been investigated. The purpose of this study was to first investigate the expression of seven different PC-related RNAs that included serine 2 (TMPRSS2): erythroblastosis virus E26 oncogene homolog (ERG) gene (TMPRSS2-ERG, T2E) fusion, alpha-methylacyl-CoA racemase (AMACR), kallikrein related peptidase 3 (KLK3), androgen receptor (AR), prostate cancer specific antigen 3 (PCA3), and matrix metalloproteinases (MMP)-2 and 9.

METHODS

PC-related RNAs were evaluated using a real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) system in pathologically ASAP-diagnosed prostate biopsy cores from 55 patients presenting with a normal digital rectal examination and a PSA level of 4-10 ng/mL.

RESULTS

We detected that positive T2E fusion status (P = 0.013) and the expression of AMACR (P = 0.016), AR (P = 0.016) and MMP-2 (P = 0.013) were independently and significantly associated with PC risk in ASAP patients. There were also several statistically significant correlations between expression levels. Additionally, we demonstrated that T2E fusion positive ASAP patients with higher MMP-2 expression were more likely to be diagnosed with PC at a subsequent biopsy during the follow-up period (P = 0.003).

CONCLUSIONS

Although, more clinical validations are needed for the stratification of PC risk in ASAP-diagnosed biopsy cores, our current results indicate that the coexistence of T2E fusion positivity with MMP-2 upregulation may help clinicians adjust their biopsy timetable and/or assessment of PC risk in ASAP-diagnosed patients with a PSA level of 4-10 ng/mL.

Measures of co-expression for improved function prediction of long non-coding RNAs

BACKGROUND

Almost 16,000 human long non-coding RNA (lncRNA) genes have been identified in the GENCODE project. However, the function of most of them remains to be discovered. The function of lncRNAs and other novel genes can be predicted by identifying significantly enriched annotation terms in already annotated genes that are co-expressed with the lncRNAs. However, such approaches are sensitive to the methods that are used to estimate the level of co-expression.

RESULTS

We have tested and compared two well-known statistical metrics (Pearson and Spearman) and two geometrical metrics (Sobolev and Fisher) for identification of the co-expressed genes, using experimental expression data across 19 normal human tissues. We have also used a benchmarking approach based on semantic similarity to evaluate how well these methods are able to predict annotation terms, using a well-annotated set of protein-coding genes.

CONCLUSION

This work shows that geometrical metrics, in particular in combination with the statistical metrics, will predict annotation terms more efficiently than traditional approaches. Tests on selected lncRNAs confirm that it is possible to predict the function of these genes given a reliable set of expression data. The software used for this investigation is freely available.

LncRNA PART1 modulates toll-like receptor pathways to influence cell proliferation and apoptosis in prostate cancer cells

We investigated thoroughly the effect of lncRNA PART1 on prostate cancer cells proliferation and apoptosis, through regulating toll-like receptor (TLR) pathways. LncRNA PART1 expression was also examined by quantitative real-time polymerase chain reactions (qRT-PCR) in human tissues and the cells lines LNCaP and PC3. After transfection with si-PART1 or control constructs, the cell viability was measured by MTS and colony formation assays. In addition, the apoptosis rate of the prostate cancer cells was validated by TUNEL staining. Relationships between lncRNA PART1 expression and TLR pathway genes were demonstrated by qRT-PCR and Western blotting. High levels of lncRNA PART1 expression were correlated with advanced cancer stage and predication of poor survival. LncRNA PART1 levels was increased in PCa cells treated with 5α-dihydrotestosterone (DHT), confirming PART1 was directly induced by androgen. Moreover, down-regulation of lncRNA PART1 inhibited prostate cancer cell proliferation and accelerated cell apoptosis. In addition, lncRNA PART1 induced downstream genes expression in TLR pathways including TLR3, TNFSF10 and CXCL13 to further influence prostate cancer cells, indicating its carcinogenesis on prostate cancer. LncRNA PART1 promoted cell proliferation ability and apoptosis via the inhibition of TLR pathways in prostate cancer. LncRNA PART1 could hence be considered as a new target in the treatment of prostate cancer.

RNAs as Candidate Diagnostic and Prognostic Markers of Prostate Cancer-From Cell Line Models to Liquid Biopsies

The treatment landscape of prostate cancer has evolved rapidly over the past five years. The explosion in treatment advances has been witnessed in parallel with significant progress in the field of molecular biomarkers. The advent of next-generation sequencing has enabled the molecular profiling of the genomic and transcriptomic architecture of prostate and other cancers. Coupled with this, is a renewed interest in the role of non-coding RNA (ncRNA) in prostate cancer biology. ncRNA consists of several different classes including small non-coding RNA (sncRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA). These families are under active investigation, given their essential roles in cancer initiation, development and progression. This review focuses on the evidence for the role of RNAs in prostate cancer, and their use as diagnostic and prognostic markers, and targets for treatment in this disease.

Urinary biomarkers of prostate cancer

The development of more specific biomarkers for prostate cancer and/or high-risk prostate cancer is necessary, because the prostate-specific antigen test lacks specificity for the detection of prostate cancer and can lead to unnecessary prostate biopsies. Urine is a promising source for the development of new biomarkers of prostate cancer. Biomarkers derived from prostate cancer cells are released into prostatic fluids and then into urine. Urine after manipulation of the prostate is enriched with prostate cancer biomarkers, which include prostate cancer cells, DNAs, RNAs, proteins and other small molecules. The urinary prostate cancer antigen 3 test is the first Food and Drug Administration-approved RNA-based urinary marker, and it helps in the detection of prostate cancer on repeat biopsy. The SelectMDx test is based on messenger RNA detection of DLX1 and HOXC6 in urine after prostate massage, and helps in the detection of high-risk prostate cancer on prostate biopsy. Exosomes are extracellular vesicles with a diameter of 30-200 nm that are secreted from various types of cells. Urinary prostate cancer-derived exosomes also contain RNAs and proteins specific for prostate cancer (e.g. PCA3 and TMPRSS2-ERG), and could be promising sources of novel biomarker discovery. The ExoDx Prostate test is a commercially available test based on the detection of three genes (PCA3, ERG and SPDEF) in urinary exosomes. Advancement of comprehensive analysis (microarray, mass spectrometry and next-generation sequencing) has resulted in the discovery of several urinary biomarkers. Non-invasive urinary markers can help in the decision to carry out prostate biopsy or in the design of a therapeutic strategy.

The use of long non-coding RNAs as prognostic biomarkers and therapeutic targets in prostate cancer

Prostate cancer is the most common cancer in men and the second leading cause of cancer-related deaths. The most used biomarker to detect prostate cancer is Prostate Specific Antigen (PSA), whose levels are measured in serum. However, it has been recently established that molecular markers of cancer should not be based solely on genes and proteins but should also reflect other genomic traits; long non-coding RNAs (lncRNAs) serve this purpose. lncRNAs are transcripts of >200 bases that do not encode proteins and that have been shown to display abnormal expression profiles in different types of cancer. Experimental studies have highlighted lncRNAs as potential biomarkers for prognoses and treatments in patients with different types of cancer, including prostate cancer, where the PCA3 lncRNA is currently used as a diagnostic tool and management strategy. With the development of genomic technologies, particularly next-generation sequencing (NGS), several other lncRNAs have been linked to prostate cancer and are currently under validation for their medical use. In this review, we will discuss different strategies for the discovery of novel lncRNAs that can be evaluated as prognostic biomarkers, the clinical impact of these lncRNAs and how lncRNAs can be used as potential therapeutic targets.

Carcinogenesis in prostate cancer: The role of long non-coding RNAs

LncRNAs appear to play a considerable role in tumourigenesis through regulating key processes in cancer cells such as proliferative signalling, replicative immortality, invasion and metastasis, evasion of growth suppressors, induction of angiogenesis and resistance to apoptosis. LncRNAs have been reported to play a role in prostate cancer, particularly in regulating the androgen receptor signalling pathway. In this review article, we summarise the role of 34 lncRNAs in prostate cancer with a particular focus on their role in the androgen receptor signalling pathway and the epithelial to mesenchymal transition pathway.