Up-regulation of long non-coding RNA PANDAR is associated with poor prognosis and promotes tumorigenesis in bladder cancer

Non-coding RNA transcripts, incredible modulators of cisplatin chemo-resistance in bladder cancer through operating a broad spectrum of cellular processes and signaling mechanism

Bladder cancer (BC) is a highly frequent neoplasm in correlation with significant rate of morbidity, mortality, and cost. The onset of BC is predominantly triggered by environmental and/or occupational exposures to carcinogens, such as tobacco. There are two distinct pathways by which BC can be developed, including non-muscle-invasive papillary tumors (NMIBC) and non-papillary (or solid) muscle-invasive tumors (MIBC). The Cancer Genome Atlas project has further recognized key genetic drivers of MIBC along with its subtypes with particular properties and therapeutic responses; nonetheless, NMIBC is the predominant BC presentation among the suffering individuals. Radical cystoprostatectomy, radiotherapy, and chemotherapy have been verified to be the common therapeutic interventions in metastatic tumors, among which chemotherapeutics are more conventionally utilized. Although multiple chemo drugs have been broadly administered for BC treatment, cisplatin is reportedly the most effective chemo drug against the corresponding malignancy. Notwithstanding, tumor recurrence is usually occurred following the consumption of cisplatin regimens, particularly due to the progression of chemo-resistant trait. In this framework, non-coding RNAs (ncRNAs), as abundant RNA transcripts arise from the human genome, are introduced to serve as crucial contributors to tumor expansion and cisplatin chemo-resistance in bladder neoplasm. In the current review, we first investigated the best-known ncRNAs, i.e. microRNAs (miRNAs), long ncRNAs (lncRNAs), and circular RNAs (circRNAs), correlated with cisplatin chemo-resistance in BC cells and tissues. We noticed that these ncRNAs could mediate the BC-related cisplatin-resistant phenotype through diverse cellular processes and signaling mechanisms, reviewed here. Eventually, diagnostic and prognostic potential of ncRNAs, as well as their therapeutic capabilities were highlighted in regard to BC management.

Identification of hub genes in bladder transitional cell carcinoma through ceRNA network construction integrated with gene network analysis

Bladder transitional cell carcinoma (BTCC) forms more than 90% of bladder cancer cases. It brings challenges to the early diagnosis and therapy of BTCC, due to lack of efficient screening biomarkers. We used weighted gene co-expression network analysis (WGCNA) combined competing endogenous RNA (ceRNA) network construction depending on TCGA datasets to investigate potential hub genes and regulatory pathways associated with occurrence and progression of BTCC. We further used real-time polymerase chain reaction (RT-PCR) to validate the relative expression genes correlated with BTCC. By WGCNA, the gene co-expression module with 11 genes was found corelated with BTCC tumour stage and prognosis after survival analyses. Ultimately, we put 100 highly stage-related genes into the above constructed ceRNA network and then constructed another new network. Among them, all elements in AC112721.1/LINC00473/AC128709.1-hsa-mir-195-RECK and LINC00460-hsa-mir-429-ZFPM2 axes were simultaneously corelated with overall survival. RT-PCR showed that AKAP12 was downregulated in tumour tissues. The hub genes screened out in the present study may provide ideals for further treatment on BTCC.

Molecular landscape of LncRNAs in bladder cancer: From drug resistance to novel LncRNA-based therapeutic strategies

Bladder cancer (BC) is a common and serious type of cancer that ranks among the top ten most prevalent malignancies worldwide. Due to the high occurrence rate of BC, the aggressive nature of cancer cells, and their resistance to medication, managing this disease has become a growing challenge in clinical care. Long noncoding RNAs (lncRNAs) are a group of RNA transcripts that do not code for proteins and are more than 200 nucleotides in length. They play a significant role in controlling cellular pathways and molecular interactions during the onset, development and progression of different types of cancers. Recent advancements in high-throughput gene sequencing technology have led to the identification of various differentially expressed lncRNAs in BC, which indicate abnormal expression. In this review, we summarize that these lncRNAs have been found to impact several functions related to the development of BC, including proliferation, cell growth, migration, metastasis, apoptosis, epithelial-mesenchymal transition, and chemo- and radio-resistance. Additionally, lncRNAs may improve prognosis prediction for BC patients, indicating a future use for them as prognostic and diagnostic biomarkers for BC patients. This review highlights that genetic tools and anti-tumor agents, such as CRISPR/Cas systems, siRNA, shRNA, antisense oligonucleotides, and vectors, have been created for use in preclinical cancer models. This has led to a growing interest in using lncRNAs based on positive research findings.

Epigenetic and Immunological Features of Bladder Cancer

Bladder cancer (BLCA) is one of the most common types of malignant tumors of the urogenital system in adults. Globally, the incidence of BLCA is more than 500,000 new cases worldwide annually, and every year, the number of registered cases of BLCA increases noticeably. Currently, the diagnosis of BLCA is based on cystoscopy and cytological examination of urine and additional laboratory and instrumental studies. However, cystoscopy is an invasive study, and voided urine cytology has a low level of sensitivity, so there is a clear need to develop more reliable markers and test systems for detecting the disease with high sensitivity and specificity. Human body fluids (urine, serum, and plasma) are known to contain significant amounts of tumorigenic nucleic acids, circulating immune cells and proinflammatory mediators that can serve as noninvasive biomarkers, particularly useful for early cancer detection, follow-up of patients, and personalization of their treatment. The review describes the most significant advances in epigenetics of BLCA.

The long non-coding RNA PANDAR regulates cell proliferation and epithelial-to-mesenchymal transition in glioma

Glioma is one of the most aggressive intracranial tumors in the central nervous system. The long non-coding RNA P21 associated ncRNA DNA damage activated (PANDAR) has been reported to be an oncogene or tumor suppressor in several cancers. However, the prognostic value and biological function of PANDAR in glioma have not been described. Here, we report that expression of PANDAR is significantly up-regulated in glioma tissues and cell lines. PANDAR expression was correlated with tumor size (p=0.044) and World Health Organization (WHO) grades (p=0.005), as shown by chi-squared test. Moreover, significant upregulation of PANDAR was found to correlate with poor prognosis in glioma, as shown using Kaplan-Meier method and Cox multivariate survival analysis. Furthermore, PANDAR knockdown suppressed cell proliferation, G1/S transition, migration and invasion, and promoted apoptosis in glioma cell lines (U251 and U87). PANDAR knockdown decreased expression of CDK4, Bcl-2, N-cadherin and Vimentin, but increased E-cadherin expression in glioma cells. In conclusion, our data suggest PANDAR as a potential prognostic biomarker and therapeutic candidate for glioma.

The multi-molecular mechanisms of tumor-targeted drug resistance in precision medicine

Clinically, cancer drug therapy is still dominated by chemotherapy drugs. Although the emergence of targeted drugs has greatly improved the survival rate of patients with advanced cancer, drug resistance has always been a difficult problem in clinical cancer treatment. At the current level of medicine, most drugs cannot escape the fate of drug resistance. With the emergence and development of gene detection, liquid biopsy ctDNA technology, and single-cell sequencing technology, the molecular mechanism of tumor drug resistance has gradually emerged. Drugs can also be updated in response to drug resistance mechanisms and bring higher survival benefits. The use of new drugs often leads to new mechanisms of resistance. In this review, the multi-molecular mechanisms of drug resistance are introduced, and the overcoming of drug resistance is discussed from the perspective of the tumor microenvironment.

Regulatory roles of lncRNA PANDAR in breast cancer cell proliferation

Background

Breast cancer represents the second most deadly malignancy in women, and long noncoding RNAs (lncRNAs) have crucial functions in its development.

Objective

To investigate effects of the promoter of CDKN1A antisense DNA damage-activated RNA (PANDAR) on epithelial-mesenchymal transition (EMT) in breast cancer cells and their proliferation.

Methods

lncRNAs potentially regulating the transcriptional activity of the E-cadherin (E-cad, an epithelial cell marker) gene promoter were screened using a dual-luciferase reporter assay. PANDAR was overexpressed in Michigan cancer foundation 7 (MCF-7) breast cancer cells. E-cad and N-cadherin (N-cad, a mesenchymal cell marker) levels were detected by immunoblotting. Cell viability was assessed using a cell counting kit-8.

Results

PANDAR and TCONS00068220/LOC105375819 conservatively regulated the promoter activity of E-cad. PANDAR overexpression in MCF-7 inhibited E-cad expression, but upregulated N-cad. The enhanced expression of PANDAR promoted cell proliferation.

Conclusion

PANDAR is a key transcriptional repressor of E-cad and has regulatory effects on the promotion of cell proliferation. PANDAR is an oncogene in breast cancer, potentially facilitating the EMT process and promoting cell proliferation.

Biological functions and clinical significance of long noncoding RNAs in bladder cancer

Bladder cancer (BCa) is one of the 10 most common cancers with high morbidity and mortality worldwide. Long noncoding RNAs (lncRNAs), a large class of noncoding RNA transcripts, consist of more than 200 nucleotides and play a significant role in the regulation of molecular interactions and cellular pathways during the occurrence and development of various cancers. In recent years, with the rapid advancement of high-throughput gene sequencing technology, several differentially expressed lncRNAs have been discovered in BCa, and their functions have been proven to have an impact on BCa development, such as cell growth and proliferation, metastasis, epithelial-mesenchymal transition (EMT), angiogenesis, and drug-resistance. Furthermore, evidence suggests that lncRNAs are significantly associated with BCa patients' clinicopathological characteristics, especially tumor grade, TNM stage, and clinical progression stage. In addition, lncRNAs have the potential to more accurately predict BCa patient prognosis, suggesting their potential as diagnostic and prognostic biomarkers for BCa patients in the future. In this review, we briefly summarize and discuss recent research progress on BCa-associated lncRNAs, while focusing on their biological functions and mechanisms, clinical significance, and targeted therapy in BCa oncogenesis and malignant progression.

Long non-coding RNAs as new players in bladder cancer: Lessons from pre-clinical and clinical studies

The clinical management of bladder cancer (BC) has become an increasing challenge due to high incidence rate of BC, malignant behavior of cancer cells and drug resistance. The non-coding RNAs are considered as key factors involved in BC progression. The long non-coding RNAs (lncRNAs) are RNA molecules and do not encode proteins. They have more than 200 nucleotides in length and affect gene expression at epigenetic, transcriptional and post-transcriptional phases. The lncRNAs demonstrate abnormal expression in BC cells and tissues. The present aims to identifying lncRNAs with tumor-suppressor and tumor-promoting roles, and evaluating their roles as regulatory of growth and migration. Apoptosis, glycolysis and EMT are tightly regulated by lncRNAs in BC. Response of BC cells to cisplatin, doxorubicin and gemcitabine chemotherapy is modulated by lncRNAs. LncRNAs regulate immune cell infiltration in tumor microenvironment and affect response of BC cells to immunotherapy. Besides, lncRNAs are able to regulate microRNAs, STAT3, Wnt, PTEN and PI3K/Akt pathways in affecting both proliferation and migration of BC cells. Noteworthy, anti-tumor compounds and genetic tools such as siRNA, shRNA and CRISPR/Cas systems can regulate lncRNA expression in BC. Finally, lncRNAs and exosomal lncRNAs can be considered as potential diagnostic and prognostic tools in BC.

LncRNA-PANDAR regulates the progression of thyroid carcinoma by targeting miR-637/KLK4

Thyroid gland carcinoma (TC) originates from follicular or parafollicular thyroid cells and is one of the most common endocrine organ malignancies. To explore the molecular mechanism by which long-chain non-coding RNAs regulate the growth and metastasis of thyroid gland carcinoma, in this study we focused on long non-coding RNAs (lncRNAs) that have been reported to be involved in tumorigenesis. We identified Promoter Region of CDKN 1A antisense DNA damage-activated RNA (PANDAR), which was positively correlated with thyroid gland carcinoma risk. PANDAR could promote thyroid gland carcinoma cell proliferation and metastasis. PANDAR negatively correlated with miR-637, and miR-637 overexpression suppressed thyroid gland carcinoma progression, which could be reversed by PANDAR. MiR-637 could target Kallikrein-related peptidases 4 (KLK4) to inhibit its expression, which was high in thyroid gland carcinoma. KLK4 inhibited cell progression in thyroid gland carcinoma cells. Knockdown of PANDAR expression inhibited cancer progression in nude mice. Overall, PANDAR can suppress miR-637 and induce KLK4 to regulate invasion and migration in thyroid gland carcinoma. Additionally, we identified miR-637 as a target of PANDAR in thyroid gland carcinoma, and PANDAR can be used as a novel therapeutic target for the treatment of thyroid gland carcinoma.

Explore prognostic biomarker of bladder cancer based on competing endogenous network

Bladder cancer (BC) is the most common tumor of the urinary tract. Increasing evidence showed that long non-coding RNA (lncRNA) is a critical regulator in cancer development and progression. However, the functions of lncRNAs in the development of BC remain mostly undefined. In the present study, based on RNA sequence profiles from The Cancer Genome Atlas database, we identified 723 lncRNAs, 157 miRNAs, and 1816 mRNAs aberrantly expressed in BC tissues. A competing endogenous RNA network, including 49 lncRNAs, 17 miRNAs, and 36 mRNAs, was then established. The functional enrichment analyses showed that the mRNAs in the ceRNA network mainly participated in ‘regulation of transcription’ and ‘pathways in cancer’. Moreover, the Cox regression analyses demonstrated that three lncRNAs (AC112721.1, TMPRSS11GP, and ADAMTS9-AS1) could serve as independent risk factors. We established a risk prediction model with these lncRNAs. Kaplan–Meier curve analysis showed that high-risk patients’ prognosis was lower than that of low-risk patients (P=0.001). The present study provides novel insights into the lncRNA-mediated ceRNA network and the potential of lncRNAs to be candidate prognostic biomarkers in BC, which could help better understand the pathological changes and pathogenesis of BC and be useful for clinical studies in the future.

Long non-coding RNA FAM83H-AS1 as an emerging marker for diagnosis, prognosis and therapeutic targeting of cancer

Incidence and mortality rates of cancer continue to increase greatly despite the improved diagnostic and therapeutic methods. Based on GLOBOCAN estimates, the numbers of new cancer cases reported in 2018 were ~18.1 million, while the numbers of cancer mortalities were ~9.6 million. It remains difficult to diagnose most cancer patients at early stages. Although cancer therapy market is rapidly evolving, the effectiveness of therapy is still inadequate. Therefore, exploring new biomarkers for diagnosis, prognosis and treatment is essential for cancer management. Long non-coding RNAs (lncRNAs) are unique regulatory molecules that control several cellular processes and are implicated in diverse human diseases including cancer. LncRNAs could serve as potential biomarkers for cancer patients to aid diagnosis and determine prognosis. In addition, numerous lncRNAs have proved their ability to predict response to cancer treatment. FAM83H antisense RNA 1 (FAM83H-AS1) is among those highly dysregulated lncRNAs in cancer. FAM83H-AS1 was demonstrated to participate in the progression of different malignancies and also shown to play a vital role in diagnosis, prognosis and treatment. Here, we analyse recent studies concerning the oncogenic role and molecular mechanisms of lncRNA FAM83H-AS1 in the following cancer types: bladder, breast, lung, hepatocellular, colorectal, gastric, pancreatic, ovarian, cervical cancer as well as glioma.

Long non-coding RNA CASC9 promotes tumor growth and metastasis via modulating FZD6/Wnt/β-catenin signaling pathway in bladder cancer

BACKGROUND

Accumulating evidence have highlighted the importance of long noncoding RNAs (lncRNAs) in multiple cancers development and progression. Cancer susceptibility candidate 9 (CASC9) is a novel long non-coding RNA and plays important regulatory role in diverse biological processes of cancers. However, the clinical significance and molecular mechanism of CASC9 in bladder cancer is still unknown.

METHODS

Comprehensive lncRNAs profiling analysis were conducted to identify lncRNAs profile alterations and uncover valuable lncRNA candidates for bladder cancer. The expression level of CASC9 was determined in a total of 106 patients with bladder cancer. Loss-of-function experiments were performed to identify the functions of CASC9 in tumor growth and metastasis of bladder cancer in vitro and in vivo. Bioinformatics analysis and further experiments were performed to explore the molecular mechanisms underlying the functions of CASC9.

RESULTS

This study found that CASC9 expression was markedly upregulated in bladder cancer and related to histological grade, TNM stage and prognosis. Knockdown of CASC9 inhibited tumor growth and metastasis of bladder cancer in vitro and in vivo. Mechanistically, we found that CASC9 functions as a miRNA sponge to positively regulate FZD6 expression and subsequently activates Wnt/β-catenin signaling pathway, thus playing an oncogenic role in bladder cancer pathogenesis.

CONCLUSION

In summary, lncRNA CASC9 plays a critical regulatory role in bladder cancer. The CASC9/miR-497-5p/ FZD6 axis provides insights for regulatory mechanism of bladder cancer, and new strategies for clinical practice.

LncRNA WEE2-AS1 promotes proliferation and inhibits apoptosis in triple negative breast cancer cells via regulating miR-32-5p/TOB1 axis

Triple negative breast cancer (TNBC) is a malignant breast cancer subtype with poor prognosis. Recent studies have revealed the critical roles of dysregulated long non-coding RNAs (lncRNAs) in many cancer types, including TNBC. LncRNA WEE2 antisense RNA 1 (WEE2-AS1) has been reported to be able to promote the progression of hepatocellular carcinoma, but the function of WEE2-AS1 in TNBC is still unknown. Therefore, in this study, we specifically researched the role of WEE2-AS1 and probed its molecular mechanism in TNBC cells. Our results showed that WEE2-AS1 was up-regulated in TNBC cell lines, and WEE2-AS1 knockdown could inhibit TNBC cell proliferation, promote apoptosis, and suppress migration and invasion. Further, we found that miR-32-5p was down-regulated in TNBC cells and could be sponged by WEE2-AS1. Moreover, miR-32-5p could target its downstream gene transducer of ERBB2, 1 (TOB1), which was highly expressed and could play the oncogenic role in TNBC cells. Through rescue assays, we proved that WEE2-AS1/miR-32-5p/TOB1 axis could modulate cancer progression in TNBC cells. In conclusion, our results demonstrated the oncogenic function of lncRNA WEE2-AS1 in TNBC cells, providing a novel insight into TNBC therapy.

Long non-coding RNA SOX2OT promotes the stemness phenotype of bladder cancer cells by modulating SOX2

BACKGROUND

Accumulating evidence indicates that long non-coding RNAs (lncRNAs) are potential biomarkers and key regulators of tumour development and progression. SOX2 overlapping transcript (SOX2OT) is a novel lncRNA that acts as a potential biomarker and is involved in the development of cancer and cancer stem cells. However, the clinical significance and molecular mechanism of SOX2OT in bladder cancer are still unknown.

METHODS

The expression level of SOX2OT was determined by RT-qPCR in a total of 106 patients with urothelial bladder cancer and in different bladder cancer cell (BCC) lines. Bladder cancer stem cells (BCSCs) were isolated from BCCs using flow cytometry based on the stem cell markers CD44 and ALDH1. Loss-of-function experiments were performed to investigate the biological roles of SOX2OT in the stemness phenotype of BCSCs. Comprehensive transcriptional analysis, RNA FISH, dual-luciferase reporter assays and western blots were performed to explore the molecular mechanisms underlying the functions of SOX2OT.

RESULTS

SOX2OT was highly expressed in bladder cancer, and increased SOX2OT expression was positively correlated with a high histological grade, advanced TNM stage and poor prognosis. Further experiments demonstrated that knockdown of SOX2OT inhibited the stemness phenotype of BCSCs. Moreover, inhibition of SOX2OT delayed xenograft tumour growth and decreased metastases in vivo. Mechanistically, we found that SOX2OT was mainly distributed in the cytoplasm and positively regulated SOX2 expression by sponging miR-200c. Furthermore, SOX2 overexpression reversed the SOX2OT silencing-induced inhibition of the BCSC stemness phenotype.

CONCLUSION

This study is the first to demonstrate that SOX2OT plays an important regulatory role in BCSCs and that SOX2OT may serve as a potential diagnostic biomarker and therapeutic target in bladder cancer.

Inhibition of lncRNA PANDAR reduces cell proliferation, cell invasion and suppresses EMT pathway in breast cancer

BACKGROUND

The PANDAR, a novel identified long non-coding RNA, is previously reported to function as oncogene in various cancers including breast cancer. the study aims to explore the role of lncRNA PANDAR for cell proliferation and invasion of breast cancer, and its underlying mechanism.

METHODS

The expression of lncRNA PANDAR in 65 pairs of breast cancer tissues and adjacent normal tissues was detected by quantitative Real-time polymerase chain reaction (qRT-PCR) assay. The association between lncRNA PANDAR expression and clinical factors of breast cancer was analyzed. Cell proliferation, cell colony formation and cell invasion assays were performed to detect the effects of lncRNA PANDAR expression tumor proliferation and invasion abilities. The western blot analysis was also performed to detected the EMT related makers expression of E-cadherin, Vimentin, MMP2 and MMP9.

RESULTS

We demonstrated that lncRNA PANDAR expression was higher in breast cancer tissues and cells compared with adjacent normal tissues and the normal mammary epithelial cell line, respectively. Higher lncRNA PANDAR expression positively associated with lymph node metastasis and advanced clinical stage in patients. In vitro, we demonstrated that knockdown of lncRNA PANDAR significantly suppressed cell proliferation, cell colony formation and cell invasion ability in breast cells. Furthermore, we verified that knockdown of lncRNA PANDAR dramatically inhibited cell epithelial-mesenchymal transition (EMT) pathway by downregulating Vimentin, MMP2 and MMP9 expression, but upregulating E-cadherin expression in breast cancer.

CONCLUSIONS

Our results proved that PANDAR may serve as potential target of breast cancer treatment.

Prognostic and Clinicopathological Significance of Long Non-coding RNA PANDAR Expression in Cancer Patients: A Meta-Analysis

Background: Long non-coding RNA PANDAR is an emerging non-coding RNA mapping to 6p21.2. It underlies metastatic progression and chromosomal instability in a variety of cancers. Despite the fact that recent studies have revealed that lncRNA PANDAR may be a potential prognostic biomarker for patients with cancer, there has still been controversy on the prognostic value of PANDAR. Methods: Databases of PubMed, Embase, SinoMed, and Web of Science were carefully searched and the literature which investigated the prognostic value of PANDAR expression among human cancers was collected for further analysis. Odds ratios (ORs) or hazards ratios (HRs) with 95% confidence intervals (CIs) were pooled to estimate the relation between PANDAR expression and survival or clinicopathological characteristics of cancer patients. Results: There were 13 eligible studies in total, with 1,465 patients enlisted in this meta-analysis. All the eligible studies complied with the case-control study. The outcome showed that the elevated expression level of PANDAR was significantly related to poor overall survival (OS) (pooled HR 1.72, 95%CI 1.14-2.60). However, high or low expression of PANDAR did not differ in the prediction of event-free survival (EFS). Moreover, we discovered that high PANDAR expression was closely related to decreased OS in colorectal cancer (pooled HR 3.43, 95%CI 2.06-5.72) and reduced expression level of PANDAR was markedly related to poor OS (pooled HR 0.65, 95%CI 0.45-0.88) in non-small cell lung cancer. However, the expression level of PANDAR had no significant association with OS in renal cell carcinoma (pooled HR 1.19, 95%CI 0.56-2.50). Moreover, after analysis, we discovered that the high expression level of PANDAR was associated closely with the depth of invasion (pooled OR 3.95, 95%CI 2.36-6.63), lymph node metastasis (pooled OR 1.92, 95%CI 0.93-3.98), tumor stage (pooled OR 2.05, 95%CI 0.99-4.27), and distant metastasis (pooled OR 2.87, 95%CI 1.60-5.16). Conclusions: Our study revealed that increased PANDAR expression may serve as an adverse prognostic biomarker for cancer patients, thus helping the clinical decision-making process.

LncRNAs act as prognostic biomarkers in bladder carcinoma: A meta-analysis

Background and purpose

Increasing studies have shown that different kinds of lncRNAs play key role in the development of multiple carcinomas. Therefore, we conducted a meta-analysis to investigate an association between the expression level of lncRNAs and the prognosis of bladder cancer (death or other clinical outcomes).

Methods

A systematic literature search was performed by using PubMed. Twenty-four studies were included in the meta-analysis based on the inclusion and exclusion criteria. In total, there are 1652 independent participants.

Results

The result showed that high expression levels of lncRNAs were demonstrated to be associated with poor overall survival (OS) (HR = 2.33, 95%CI: 1.51–2.39, p < 0.01) in bladder carcinoma, but there was no significant correlation between lncRNAs level and recurrence-free survival (RFS) (pooled HR = 1.57, 95%CI 0.69–3.56, p = 0.284), and progression-free survival (PFS) (pooled HR = 1.37, 95%CI 0.79–2.38, p = 0.269). Additionally, increased lncRNAs expression was found to be moderately correlated with tumor stage and progression (II/III/IV vs. I, OR = 3.20, 95%CI: 1.72–5.98, p < 0.001). In addition, elevated lncRNAs expression predicted lymph node metastasis (LNM) significantly (pooled OR = 2.29, 95 % CI 1.33–3.95, p < 0.01). No significant heterogeneity was observed among studies except lymph node metastasis.

Conclusion

In conclusion, high expression levels of lncRNAs were demonstrated to be associated with poor OS and positive LNM, and lncRNAs might be potential prognostic markers in bladder cancer.

Long noncoding RNA AC114812.8 promotes the progression of bladder cancer through miR-371b-5p/FUT4 axis

Bladder cancer (BC) brings a heavy burden to afflicted patients worldwide. In order to find new diagnostic markers and therapeutic targets for this disease, we investigated the role of a novel lncRNA, AC114812.8, in bladder cancer progression. Clone formation and CCK-8 assays were used to detect the proliferative capacity of the cells, and the transwell assay was used to explore their invasion and migration abilities. Wound healing experiments were also used to detect cell migration. Luciferase reporter assays were used to investigate the interactions between lncRNA, target gene and miRNA. The expression of FUT4 and marker genes related to epithelial-mesenchymal transition was explored through western blot analysis. Our findings revealed that AC114812.8 was significantly upregulated in BC and could markedly facilitate the proliferation, migration, and invasion of bladder cancer cells both in vitro and in vivo. Furthermore, duel-luciferase reporter assay revealed that AC114812.8 could regulate the FUT4 expression level by sponging miR-371b-5p to facilitate BC progression. We detected the levels of EMT-related biomarkers in AC114812.8-overexpressing BC cells by western blot analysis and found that AC114812.8 could promote EMT process. Rescue experiments showed that miR-371b-5p could rescue the effect of AC114812.8 on proliferation and metastasis of BC. Our results suggest that AC114812.8 could be a novel prognostic biomarker and therapeutic target for bladder cancer.

Long non-coding RNAs in non-small cell lung cancer: functions and distinctions from other malignancies

Lung cancer leads to the most cancer-related death in the world. It was shown from the increasing evidences that long non-coding RNAs (lncRNAs) are emerging as molecules for diagnosis, prognosis and even therapy of lung cancer and other malignancies. The biological functions or involved signaling pathways of lncRNAs are always found to be inconsistent among different types of malignancies. However, no available literature has systemically summarized differences in the functions and underlying molecular mechanisms of lncRNAs between lung cancer and other cancers. In this review, the biological functions and molecular mechanisms of lncRNAs in lung cancer were introduced. Furthermore, their functional differences between lung cancer and other malignancies were discussed. Finally, their potential clinical applications in future lung cancer therapy were focused on.

Long noncoding RNAs in cancer: From discovery to therapeutic targets

Long noncoding RNAs (lncRNAs) have recently gained considerable attention as key players in biological regulation; however, the mechanisms by which lncRNAs govern various disease processes remain mysterious and are just beginning to be understood. The ease of next-generation sequencing technologies has led to an explosion of genomic information, especially for the lncRNA class of noncoding RNAs. LncRNAs exhibit the characteristics of mRNAs, such as polyadenylation, 5' methyl capping, RNA polymerase II-dependent transcription, and splicing. These transcripts comprise more than 200 nucleotides (nt) and are not translated into proteins. Directed interrogation of annotated lncRNAs from RNA-Seq datasets has revealed dramatic differences in their expression, largely driven by alterations in transcription, the cell cycle, and RNA metabolism. The fact that lncRNAs are expressed cell- and tissue-specifically makes them excellent biomarkers for ongoing biological events. Notably, lncRNAs are differentially expressed in several cancers and show a distinct association with clinical outcomes. Novel methods and strategies are being developed to study lncRNA function and will provide researchers with the tools and opportunities to develop lncRNA-based therapeutics for cancer.

Long Noncoding RNAs in Acute Myeloid Leukemia: Functional Characterization and Clinical Relevance

Acute Myeloid Leukemia (AML) is the most common form of leukemia in adults with an incidence of 4.3 per 100,000 cases per year. Historically, the identification of genetic alterations in AML focused on protein-coding genes to provide biomarkers and to understand the molecular complexity of AML. Despite these findings and because of the heterogeneity of this disease, questions as to the molecular mechanisms underlying AML development and progression remained unsolved. Recently, transcriptome-wide profiling approaches have uncovered a large family of long noncoding RNAs (lncRNAs). Larger than 200 nucleotides and with no apparent protein coding potential, lncRNAs could unveil a new set of players in AML development. Originally considered as dark matter, lncRNAs have critical roles to play in the different steps of gene expression and thus affect cellular homeostasis including proliferation, survival, differentiation, migration or genomic stability. Consequently, lncRNAs are found to be differentially expressed in tumors, notably in AML, and linked to the transformation of healthy cells into leukemic cells. In this review, we aim to summarize the knowledge concerning lncRNAs functions and implications in AML, with a particular emphasis on their prognostic and therapeutic potential.

Plasma long noncoding RNAs PANDAR, FOXD2-AS1, and SMARCC2 as potential novel diagnostic biomarkers for gastric cancer

Background

Gastric cancer is still a common cancer worldwide. Investigation of potential plasma biomarkers for gastric cancer diagnosis is essential for prevention strategies and early intervention for gastric cancer-control planning.

Objectives

This study was aimed to explore the lncRNAs' promoter of CDKN1A antisense DNA-damage-activated RNA (PANDAR), FOXD2-AS1, and SMARCC2 as potential novel diagnostic biomarkers for gastric cancer.

Method

109 gastric cancer patients and 106 healthy controls were involved in this study. Plasma lncRNAs PANDAR, FOXD2-AS1, and SMARCC2 were detected by real-time PCR. Student's t-test, Mann-Whitney U test, and Chi-square test were used to verify the differences of clinical variables between two groups. Receiver operating characteristic curve (ROC) was used to evaluate the diagnostic value of every biomarker. Multivariable analysis of risk factors for gastric cancer was performed using logistic regression analysis.

Results

There were significant differences in age, gender, carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 153 between gastric cancer and healthy controls (P<0.05). Compared with healthy subjects, the levels of plasma lncRNAs PANDAR, FOXD2-AS1, and SMARCC2 were all significantly higher in gastric cancer patients (P<0.05). These lncRNAs were significantly associated with clinicopathological parameters of gastric cancer, like pathological differentiation, TNM stage, and/or lymph nodes metastasis, and/or invasion depth (P<0.05). The AUC for lncRNA PANDAR was 0.767, for FOXD2-AS1 was 0.700, for SMARCC2 was 0.748, and the AUC of the combinative diagnostic value of these three lncRNAs was 0.839. Adjusted by other variables, these lncRNAs' expressions were significantly associated with gastric cancer.

Conclusions

Plasma lncRNAs PANDAR, FOXD2-AS1, and SMARCC2 might be appropriate diagnostic biomarkers for gastric cancer.

Long Non-coding Ribonucleic Acid as a Novel Diagnosis and Prognosis Biomarker of Bladder Cancer

Long non-coding ribonucleic acids (lncRNAs) are the largest group of non-coding RNAs and supposedly have a broad spectrum of diverse functions in normal cellular processes. This study was carried out to review the biological functions of candidate lncRNAs (i.e., H19, MALAT-1, TUG1, UCA-1, MEG-3, HOTAIR, CCAT2, AATBC, and the like) with aberrant expressions that play critical roles in bladder cancer (BC) initiation, progression, and metastasis. A formal narrative review was performed by searching the PubMed database for English articles using a combination of keywords such as "long non-coding RNA", "lncRNA", "cancer", "bladder cancer", "screening", "prognosis", "diagnosis", and "response to therapy". In addition, the existing literature was studied on biological function, aberrant expression, and the clinical applications of candidate lncRNAs in BC. By a better understanding of the molecular mechanisms of lncRNAs, they can be used as biomarkers for tumor signatures in urologic malignancies, which can improve screening, prognosis, diagnosis, and the treatment of BC.

MiR-101 acts as a novel bio-marker in the diagnosis of bladder carcinoma

MiR-101 plays an important role in tumorigenesis. The aim of this study was to estimate diagnostic potential of serum miR-101 in bladder cancer.Serum level of miR-101 in 122 bladder cancer patients and 110 healthy volunteers was detected using quantitative real-time polymerase chain reaction method. The association between miR-101 expression and clinicopathological characteristic was analyzed via χ test. Then receiver operating characteristic (ROC) curve was plotted to evaluate diagnostic value of serum miR-101 in bladder cancer.MiR-101 expression was statistically down-regulated in bladder cancer patients compared to healthy controls. MiR-101 expression was significantly associated with TNM stage (P = .019), pathological grade (P = .006) and lymph node metastasis (P = .010). ROC analysis suggested that miR-101 had high value in discriminating between bladder cancer patients and healthy individuals with an AUC value of 0.884. The cut-off value for serum miR-101 in bladder cancer diagnosis was 1.645, with a sensitivity of 82.0% and a specificity of 80.9%.MiR-101 is decreased in bladder cancer patients, and shows negative association with aggressive clinical characteristics. MiR-101 may serve as a bio-marker in diagnosing bladder cancer.

LncRNAs Regulatory Networks in Cellular Senescence

Long noncoding RNAs (lncRNAs) are a class of transcripts longer than 200 nucleotides with no open reading frame. They play a key role in the regulation of cellular processes such as genome integrity, chromatin organization, gene expression, translation regulation, and signal transduction. Recent studies indicated that lncRNAs are not only dysregulated in different types of diseases but also function as direct effectors or mediators for many pathological symptoms. This review focuses on the current findings of the lncRNAs and their dysregulated signaling pathways in senescence. Different functional mechanisms of lncRNAs and their downstream signaling pathways are integrated to provide a bird’s-eye view of lncRNA networks in senescence. This review not only highlights the role of lncRNAs in cell fate decision but also discusses how several feedback loops are interconnected to execute persistent senescence response. Finally, the significance of lncRNAs in senescence-associated diseases and their therapeutic and diagnostic potentials are highlighted.

Long non-coding RNAs in retinoblastoma

Retinoblastoma represents 3% of all childhood cancers and is the most common intraocular malignant tumor with a highly aggressive and metastatic phenotype. While recent genetic and epigenetic studies have reported new insights into the mechanism of retinoblastoma development, the involvement of regulatory non-coding RNAs remains unclear. Long non-coding RNAs (lncRNAs) are a group of endogenous non-protein-coding RNAs with the capacity to regulate gene expression at multiple levels. Recent evidence has shown that lncRNAs can regulate many cellular processes, such as cell proliferation, differentiation, migration, and invasion. Several lncRNAs, including BANCR, AFAP1-AS1, NEAT1, XIST, ANRIL, PlncRNA-1, HOTAIR, PANDAR, DANCR, and THOR, promote the progression and metastasis of retinoblastoma. However, some lncRNAs, such as MEG3, MT1JP, and H19, play a tumor suppressive role. Our review summarizes the functional role of lncRNAs in retinoblastoma and their potential clinical applications for diagnosis, prognosis, and treatment.

Long non-coding RNAs are emerging targets of phytochemicals for cancer and other chronic diseases

The long non-coding RNAs (lncRNAs) are the crucial regulators of human chronic diseases. Therefore, approaches such as antisense oligonucleotides, RNAi technology, and small molecule inhibitors have been used for the therapeutic targeting of lncRNAs. During the last decade, phytochemicals and nutraceuticals have been explored for their potential against lncRNAs. The common lncRNAs known to be modulated by phytochemicals include ROR, PVT1, HOTAIR, MALAT1, H19, MEG3, PCAT29, PANDAR, NEAT1, and GAS5. The phytochemicals such as curcumin, resveratrol, sulforaphane, berberine, EGCG, and gambogic acid have been examined against lncRNAs. In some cases, formulation of phytochemicals has also been used. The disease models where phytochemicals have been demonstrated to modulate lncRNAs expression include cancer, rheumatoid arthritis, osteoarthritis, and nonalcoholic fatty liver disease. The regulation of lncRNAs by phytochemicals can affect multi-steps of tumor development. When administered in combination with the conventional drugs, phytochemicals can also produce synergistic effects on lncRNAs leading to the sensitization of cancer cells. Phytochemicals target lncRNAs either directly or indirectly by affecting a wide variety of upstream molecules. However, the potential of phytochemicals against lncRNAs has been demonstrated mostly by preclinical studies in cancer models. How the modulation of lncRNAs by phytochemicals produce therapeutic effects on cancer and other chronic diseases is discussed in this review.

Long non-coding RNA DANCR promotes malignant phenotypes of bladder cancer cells by modulating the miR-149/MSI2 axis as a ceRNA

BACKGROUND

Accumulating evidences have indicated that long non-coding RNAs (lncRNAs) are potential biomarkers that play key roles in tumor development and progression. Differentiation antagonizing non-protein noding RNA (DANCR) is a novel lncRNA that acts as a potential biomarker and is involved in the development of cancers. However, the clinical significance and molecular mechanism of DANCR in bladder cancer is still unknown.

METHODS

The relative expression level of DANCR was determined by Real-Time qPCR in a total of 106 patients with urothelial bladder cancer and in different bladder cancer cell lines. Loss-of-function experiments were performed to investigate the biological roles of DANCR on bladder cancer cell proliferation, migration, invasion and tumorigenicity. Comprehensive transcriptional analysis, RNA-FISH, dual-luciferase reporter assay and western blot were performed to explore the molecular mechanisms underlying the functions of DANCR.

RESULTS

In this study, we found that DANCR was significantly up-regulated in bladder cancer. Moreover, increased DANCR expression was positively correlated with higher histological grade and advanced TNM stage. Further experiments demonstrated that knockdown of DANCR inhibited malignant phenotypes and epithelial-mesenchymal transition (EMT) of bladder cancer cells. Mechanistically, we found that DANCR was distributed mostly in the cytoplasm and DANCR functioned as a miRNA sponge to positively regulate the expression of musashi RNA binding protein 2 (MSI2) through sponging miR-149 and subsequently promoted malignant phenotypes of bladder cancer cells, thus playing an oncogenic role in bladder cancer pathogenesis.

CONCLUSION

This study is the first to demonstrate that DANCR plays a critical regulatory role in bladder cancer cell and DANCR may serve as a potential diagnostic biomarker and therapeutic target of bladder cancer.

The cisplatin-induced lncRNA PANDAR dictates the chemoresistance of ovarian cancer via regulating SFRS2-mediated p53 phosphorylation

As a component of p53-dependent lncRNA (long non-coding RNA), PANDAR (the promoter of CDKN1A antisense DNA damage activated RNA) participates in the epigenetic regulation in human cancer. However, the involvement of PANDAR in cancer chemoresistance is unknown. In this study, we report that PANDAR serves as a negative regulator of cisplatin sensitivity in human ovarian cancer via PANDAR-SRFS2-p53 feedback regulation in nuclear. Our data showed that among the drugs commonly used in ovarian cancer therapy, cisplatin induces higher levels of PANDAR compared with doxorubicin and paclitaxel. We also proved that PANDAR exhibited higher expression in cisplatin-resistant ovarian cancer tissues and cells, compared with cisplatin-sensitive ones, and this expression pattern depends on wild-type p53 (wt-p53), not mutant-p53 (mt-p53). In vitro and in vivo, PANDAR overexpression improved cell survival rate and tumor growth in response to cisplatin, while depletion of PANDAR leads to a reduced tumor growth. Further investigation revealed that PANDAR-reduced cisplatin sensitivity was likely or partly due to the PANDAR-binding protein SFRS2 (arginine/serine-rich 2), a splicing factor with the ability to negative regulate p53 and its phosphorylation at Serine 15 (Ser15). This feedback regulation of PANDAR–SFRS2–p53 leads to a reduced transactivation of p53-related pro-apoptotic genes, such as PUMA (p53-upregulated modulator of apoptosis). In addition, in platinum-treated patients with relapsed ovarian cancer, resistant period was positively correlated with the expression of PANDAR and SFRS2, and inversely associated with expression of p53-Ser15 and PUMA in these clinical tissues. Last but not least, the role of PANDAR in chemoresistance was confirmed in patients with ovarian cancer. These findings reveal a novel regulatory maneuver of cancer cells in response to chemostress, and might shed light on overcoming cisplatin resistance in ovarian cancer.

Overexpression of long non‑coding RNA n346372 in bladder cancer tissues is associated with a poor prognosis

Accumulating evidence has confirmed that dysregulated long non-coding RNAs (lncRNAs) participate in the initiation and progression of a number of solid tumors and have potential applications for early diagnosis, targeted therapy, and the prognosis of patients with bladder cancer. In the present study, via high-throughput sequencing technology and bioinformatics analysis, a total of 169 lncRNAs with significantly differential expression between bladder cancer tissues and paired adjacent normal tissues (n=10) were initially identified by screening. Reverse-transcription-quantitative polymerase chain reaction was carried out to validate the expression levels of lncRNA-n346372 in 60 pairs of tissue samples from bladder cancer patients. The results indicated that lncRNA-n346372 was upregulated in bladder cancer tissues compared with the matched adjacent normal tissues (P<0.05). In addition, the results of fluorescence in situ hybridization analysis of bladder cancer cells and tissues demonstrated that lncRNA-n346372 is located in the cytoplasm, and the expression of lncRNA-n346372 in bladder cancer tissues was significantly increased compared with the paired normal tissues. Following a χ² test with common clinical variables among the patients, the expression level of lncRNA-n346372 was demonstrated to be positively associated with advanced tumor stage and poor histological differentiation of bladder cancer. Kaplan-Meier survival analysis revealed that patients with high expression of n346372 were more likely to have a poor prognosis compared with patients with low n346372 expression. Finally, univariate and multivariate analyses indicated that the relative level of n346372, apart from tumor stage and histological grade, may serve as an independent prognostic factor of bladder cancer. To the best of the authors' knowledge, this is the first study to verify the dysregulated expression of lncRNA-n346372 in bladder cancer; an association of this lncRNA with overall survival of bladder cancer patients was also uncovered in the present study, suggesting that lncRNA-n346372 may contribute to the initiation and/or progression of bladder cancer with potential applications in the clinic.

LncRNA as a diagnostic and prognostic biomarker in bladder cancer: a systematic review and meta-analysis

Background

Bladder cancer is one of the most common urinary malignancies, and has a high recurrence rate and poor outcomes. In order to identify novel diagnostic and prognostic biomarkers for bladder cancer, we conducted a meta-analysis to analyze the association between long non-coding RNA (lncRNA) expression and survival in bladder cancer.

Materials and methods

We searched literature from databases using our inclusion and exclusion criteria. STATA 14.0 software was used to analyze the data from collected studies and to construct the forest plots. A different effect size was selected for each meta-analysis.

Results

After selection, 30 articles were found to be eligible. The present meta-analysis contains data from 13 articles about clinicopathological characteristics, six articles about diagnosis, and 16 articles about prognosis. In the present study, we found that many lncRNAs could function as potential diagnostic and prognostic markers in bladder cancer. Among these findings, UCA1 was expected to be a diagnostic biomarker for bladder cancer, while the aberrant expression of HOTAIR and GAS5 was associated with poor disease-free survival/recurrence-free survival/disease-specific survival.

Conclusion

Overall, the present study is the first meta-analysis to assess the association between expression of lncRNAs and clinical value in patients with bladder cancer. LncRNAs hold promise as novel diagnostic and prognostic markers in bladder cancer.

SP1-induced upregulation of lncRNA PANDAR predicts adverse phenotypes in retinoblastoma and regulates cell growth and apoptosis in vitro and in vivo

Retinoblastoma (RB) is an intraocular malignancy for children and has a high mortality rate. Long non-coding RNAs (lncRNAs) are emerging as gene regulators and biomarkers in various malignancies. PANDAR is a novel cancer-related lncRNA that dysregulated in several types of cancers. However, its clinical value and potential effects on RB remains unclear. RT-qPCR was used to assess the relative expression of PANDAR in RB tissues and cells. Additionally, chromatin immunoprecipitation (ChIP) and luciferase reporter assays were performed to investigate whether SP1 could bind to the promoter region of PANDAR and activate its transcription. Furthermore, in vitro and in vivo studies were induced to elucidate the biological functions of PANDAR. The results indicated that PANDAR was increased in RB tissues and cells, and this upregulation was associated with advanced IIRC stage, positive optic nerve invasion, and lower differentiation grade in RB patients. In addition, SP1 could bind directly to the PANDAR promoter region and activate its transcription. Furthermore, PANDAR silencing yielded tumor suppressive effects both in vitro and in vivo. Importantly, PANDAR protects against apoptosis partly by affecting Bcl-2/caspase-3 pathway. Ultimately, our work first illustrate that PANDAR plays an oncogenic role in RB and may offer a potential therapeutic target for treating this devastating disease.

Long non-coding RNA expression in bladder cancer

The advent of novel high-throughput sequencing methods has facilitated identification of non-coding RNAs with fundamental roles in cellular biological and pathological conditions. A group of these consisting of at least 200 nucleotides are called long non-coding RNAs (lncRNAs). Their participation in the pathogenesis of cancer has been highlighted in recent years. Bladder cancer, one of the most prevalent cancers worldwide, exhibits altered expression levels of several lncRNAs. Several in vitro and in vivo studies have assessed the effects of silencing RNAs on cancer cell phenotypes and in vivo tumor growth. For instance, in vitro studies have shown that nuclear paraspeckle assembly transcript 1 (NEAT1), promoter of CDKN1A antisense DNA damage-activated RNA(PANDAR) and metastasis-associated lung adenocarcinoma transcript 1(MALAT1) have oncogenic effects while Maternally expressed 3 (MEG3) and BRAF activated non-coding RNA (BANCR) are tumor suppressors. Analysis of these data will help to identify a panel of lncRNAs that can be potentially used for both early detection and prognosis in bladder cancer patients. Here, we review the roles of several lncRNAs in the oncogenesis, tumor suppression, early detection, and prognosis of bladder cancer.

PANDAR: a pivotal cancer-related long non-coding RNA in human cancers

Long non-coding RNAs (lncRNAs), non-protein-coding RNAs that are more than 200 nucleotides in length, have been demonstrated to play a vital role in the pathophysiology of human diseases, particularly in tumorigenesis and progression of cancers. Dysregulation of lncRNAs, which serve as either oncogenes or tumor suppressor genes, is involved in diverse cellular processes, such as proliferation, dedifferentiation, migration, invasion and anti-apoptosis. Promoter of CDKN1A antisense DNA damage-activated RNA (PANDAR), which was recently found to manifest aberrant expression in various malignancies including non-small cell lung cancer, hepatocellular carcinoma, colorectal cancer and gastric cancer, is a novel cancer-related lncRNA. Deregulation of PANDAR contributes to tumorigenesis and progression of cancers, suggesting that PANDAR is likely to represent a viable biomarker and therapeutic target for human cancers. In this review, we summarize current evidence regarding the biological functions and mechanisms of PANDAR during tumor development.

Clinical Values of Long Non-coding RNAs in Bladder Cancer: A Systematic Review

Background: Increasing evidence shows that dysregulated expression of long non-coding RNAs (lncRNAs) can serve as diagnostic or prognostic markers in bladder cancer. The aim of this study was to evaluate the clinical values of dysregulated lncRNAs in bladder cancer.

Methods: Eligible studies were systematically searched in PubMed, Embase, and Web of Science databases from inception to December 2017. Odds ratios (OR) were calculated to investigate the correlation between lncRNAs and clinicopathological parameters. Pooled hazard ratios (HR) and 95% confidence interval (CI) were calculated to explore the prognostic value of lncRNAs in bladder cancer. Pooled diagnostic parameters were also calculated to estimate the performance of lncRNAs in diagnosing bladder cancer. All statistical analyses were performed by using STATA 13.1 program.

Results: A total of 37 relevant studies were included to the present systematic review according to the inclusion and exclusion criteria, including 26 on clinicopathological parameters, 19 on prognosis, and 7 on diagnosis. For clinicopathological parameters, MALAT1 expression was significantly associated with lymph node metastasis (OR = 2.731; 95% CI: 1.409–5.292; p = 0.003), and high-level expression of XIST was related to larger tumor size (OR = 2.473; 95% CI: 1.159–5.276; p = 0.019) and higher TNM stage (OR = 0.400; 95% CI, 0.184–0.868; p = 0.020). For the prognostic values, the most significant association was observed between increased expressions of SPRY4-IT1 and poor overall survival (OS) (HR = 3.716; 95% CI: 2.084–6.719; p < 0.001); high MALAT1 expression was significantly associated with poor OS (HR = 1.611; 95% CI: 1.076–2.412; p = 0.020). For the diagnostic values, UCA1 expression profile achieved a combined AUC of 0.92, with sensitivity of 0.84 and specificity of 0.89 in distinguishing patients with bladder cancer from non-cancerous controls.

Conclusions: In summary, systematic review elaborated that abnormal lncRNAs expression can serve as potential markers for prognostic evaluation in bladder cancer patients. In addition, the diagnostic meta-analysis concluded that abnormally expressed UCA1 can function as potential diagnostic markers for bladder cancer.

Long non-coding RNA PANDAR promotes melanoma cell invasion through regulating epithelial-mesenchymal transition

Melanoma is a malignant skin tumor and has a poor cure rate because of its high metastatic potential. Overexpression of long non-coding (lnc) RNA PANDAR has been observed in several kinds of cancer, but the function of PANDAR on melanoma is still unclear. Therefore, this study was to explore the mechanism of PANDAR on the occurrence and progression in malignant melanoma. We detected expression of PANDAR in malignant melanoma tissues and cell lines by qRT-PCR and analyzed correlation of PANDAR expression with the patients' prognosis. Furthermore, we investigated the effects of PANDAR on cell viability, migration, invasion, tumorigenesis, and epithelial-mesenchymal transition (EMT) using CCK-8, Transwell, and nude mouse subcutaneous tumor formation model assays and Western blotting analysis, respectively. From the results, we discovered that the PANDAR expression is strikingly upregulated in melanoma tissues compared with paired-adjacent non-tumorous tissues and elevated PANDAR is positively correlated with short overall survival time. The results also demonstrate that knockdown of PANDAR inhibits cell viability, migration, invasion, tumorigenesis, and EMT, whereas overexpression of PANDAR gave opposite results by promoting cell viability, migration, invasion, tumorigenesis, and EMT of melanoma cells. These new findings all illustrate that PANDAR might play a pivotal oncogenic role in the occurrence and development of melanoma, and PANDAR might promote melanoma cell invasion through regulating EMT, providing a potential diagnostic and therapeutic target for melanoma.

Long non-coding RNA PANDAR overexpression serves as a poor prognostic biomarker in oral squamous cell carcinoma

BACKGROUND

Long non-coding RNA (lncRNA) has been found to play a crucial role in carcinogenesis and in evaluating prognosis of multiple neoplasms. PANDAR (promoter of CDKN1A antisense DNA damage activated RNA), a newly discovered cancer-associated RNA is abnormally expressed in a wide variety of tumors. Expression and the functional role of PANDAR in human oral squamous cell carcinoma (OSCC), however, needs to be completely elucidated.

METHODS

Quantitative real-time PCR (qRT-PCR) was applied to detect expression levels of lncRNA PANDAR in OSCC tissues and corresponding paracancerous normal tissues in 92 OSCC patients, four OSCC cell lines, and a normal oral keratinocytes cell line. Association between expression of PANDAR and clinicopathological features of OSCC patients was also analyzed. For analysis of overall survival data, Kaplan-Meier curves were constructed. The prognostic value of PANDAR was examined by Cox regression analysis. PANDAR levels were knocked down in OSCC cell line Tca8113 by using PANDAR siRNA. Function of PANDAR on tumor cell proliferation, migration, and invasion was further evaluated by MTT and Transwell assays in vitro.

RESULTS

PANDAR was highly expressed in OSCC tissues and cell lines (P < 0.05) and its high expression level was found to be closely associated with advanced TNM stage (P = 0.004) and positive distant metastasis (P = 0.001). Furthermore, overall survival rate of OSCC patients with high PANDAR expression was poorer than patients with low PANDAR expression (P < 0.001). Cox proportional hazards model analysis showed that expression level of PANDAR can be used as an independent prognostic indicator for OSCC. Functionally, knockdown of PANDAR can inhibit proliferation, invasion, and migration of OSCC cells.

CONCLUSIONS

Our findings indicate that PANDAR may serve as a promising prognostic biomarker and a new molecular target for new therapies for OSCC patients.

Increased expression of long non-coding RNA CCEPR is associated with poor prognosis and promotes tumorigenesis in urothelial bladder carcinoma

Recent emerging evidences have showed that long non-coding RNAs play important regulatory roles in diverse biological processes of tumor development and progression. CCEPR (cervical carcinoma expressed PCNA regulatory lncRNA) is a novel identified lncRNA that acts as a potential biomarker and involves in development and progression of cervical carcinoma. Nevertheless, we know nothing about the clinical significance and molecular mechanism of CCEPR in bladder cancer. In this study, we found that CCEPR was significantly up-regulated in bladder cancer. Furthermore, up-regulated CCEPR expression was positively correlated with advanced TNM stage and higher histological grade. Moreover, further experiments demonstrated that CCEPR promotes cell proliferation and suppresses cell apoptosis in bladder cancer. Mechanistically, we found CCEPR upregulates the expression of PCNA in mRNA and protein level to promote cancer growth. In conclusions, these findings demonstrated that CCEPR plays an important regulatory role in bladder cancer and may serve as a potential diagnostic biomarker and therapeutic target.

High expression of long noncoding RNA NORAD indicates a poor prognosis and promotes clinical progression and metastasis in bladder cancer

PURPOSE

To explore the function of NORAD in bladder cancer (BC), and to verify whether NORAD could be used as a biomarker to determine preoperative presence of progression and lymph node metastasis. To our knowledge, it is the first study investigating NORAD and its implications in BC.

METHODS

BC specimens of 90 patients underwent bladder cystectomy or transurethral resection between January 2012 to December 2016 were tested by fluorescence in situ hybridization. The association between NORAD expression and clinicopathological features and prognosis of the patients was analyzed using Kaplan-Meier survival analysis and Cox regression analysis. Quantitative real-time polymerase chain reaction was performed in 4 BC cell lines and 10 fresh tumor sample together with adjacent tissues. MTT, colony formation assay, and Annexin-V apoptosis detection were performed after knockdown of NORAD using shRNA in TSSCUP cells. Western blot was performed to related proteins extracted from these cells.

RESULTS

Fluorescence in situ hybridization indicated that high NORAD expression was associated with more advanced histological grade and clinical stage for patients with BC. Higher NORAD expression resulted in lower overall survival, and was an independent prognostic indicator. Real-time polymerase chain reaction showed that the expression of NORAD in BC tissues was higher than those measured in adjacent normal tissues. MTT and colony formation assay demonstrated that knockdown of NORAD results in lower proliferation in TSSCUP cells, whereas PUM2 expression was upregulated and E2F3 downregulated.

CONCLUSIONS

High NORAD expression could serve as an independent prognostic factor for overall survival of patients with transitional BC. NORAD could be considered as a promising candidate for novel biomarker and therapeutic target for human BC.

Overexpression of CRNDE promotes the progression of bladder cancer

Accumulating evidences indicate that long non-coding RNAs (lncRNAs) are indispensable in cancer initiation and progression. Dysregulation of functional lncRNAs can promote the development of cancers. Previous research have revealed that augmented expression of CRNDE caused poor prognosis of cancer patients and facilitate the tumor progress in various cancers. Nevertheless, the underlying roles of CRNDE in bladder cancer progression are not entirely clear. To further identify the effects CRNDE in bladder cancer progression, we performed the gain and loss of function assay. In this work, we have presented evidence that CRNDE was significantly increased in bladder cancer, and overexpressed expression of CRNDE was positively related with advanced TNM stage of bladder cancer patients. In addition, in vitro experiments showed that CRNDE strengthened cell migration/proliferation and inhibited cell apoptosis in bladder cancer. To sum up, our results exhibited new understand into the role of lncRNA CRNDE in the development of bladder cancer.

A potential prognostic lncRNA signature for predicting survival in patients with bladder urothelial carcinoma

Increasing evidence has highlighted the critical roles of long non-coding RNA (lncRNA) in cancer development and progression. However, the prognostic power of expression-based lncRNA signature for predicting overall survival in patients with Bladder Urothelial Carcinoma (BLCA) has not been investigated. Here, we performed a comprehensive analysis for lncRNA expression profiles and corresponding clinical information of 234 BLCA patients from The Cancer Genome Atlas (TCGA). We established a set of four-lncRNAs that were significantly associated with BLCA patients’ survival. Using the prognostic four-lncRNA signature, we successfully classified the BLCA patients into high-risk and low-risk groups, and the prognostic power of the four-lncRNA signature was further validated in the testing dataset and entire dataset. Multivariate Cox regression and stratified analyses demonstrated that the prognostic power of the four-lncRNA signature was independent of other clinical variables. Functional enrichment analyses suggested the four prognostic lncRNAs may be involved in known BLCA-related biological processes and pathways. Our results demonstrated that the four-lncRNA signature could be novel independent biomarkers for predicting survival in patients with BLCA.

Identification of novel PANDAR protein interaction partners involved in splicing regulation

Interactions of long non-coding RNAs (lncRNA) with proteins play important roles in the regulation of many cellular processes. PANDAR (Promotor of CDKN1AAntisense DNA damage Activated RNA) is a lncRNA that is transcribed in a p53-dependent manner from the CDKN1A promoter and is involved in the regulation of proliferation and senescence. Overexpression of PANDAR has been observed in several tumor species and correlated with a poor prognosis for patient survival rate. Depending on the cellular state, PANDAR is known to interact with proteins such as the nuclear transcription factor Y subunit A (NF-YA) and the scaffold attachment factor A (SAF-A). However, a comprehensive analysis of the PANDAR interactome was missing so far. Therefore, we applied peptide nucleic acid (PNA)-based pull-downs combined with quantitative mass spectrometry to identify new protein binding partners. We confirmed potential candidates like U2AF65 and PTBP1, known to be involved in RNA processing. Furthermore, we observed that overexpression of PANDAR leads to a reduced level of the short pro-apoptotic BCL-X splice variant (BCL-XS) which is regulated by PTBP1. Simultaneous overexpression of PTBP1 was able to rescue this effect. Overall, our data suggest a role for PANDAR in the regulation of splicing events via its interaction partner PTBP1.

Long noncoding RNA PANDAR blocks CDKN1A gene transcription by competitive interaction with p53 protein in gastric cancer

Emerging evidence indicates that lncRNAs play important roles in cancer tumourigenesis and could be used as potential diagnostic biomarkers or therapeutic targets. However, the clinical significance and molecular mechanism of lncRNAs in gastric cancer (GC) is still unclear. The aim of this study was to explore the expression and role of lncRNAs in GC. The relative expression level of lncRNAs in GC samples was examined by an lncRNA microarray analysis, northern blot analysis and qRT-PCR analysis. A Kaplan−Meier survival analysis and univariate and multivariate Cox proportional hazards models were performed to evaluate the clinical and prognostic significance of PANDAR (promoter of CDKN1A antisense DNA damage activated RNA) in GC patients. The binding activity of PANDAR with the p53 protein was analysed by an RNA immunoprecipitation analysis and RNA pull-down analysis. The depletion of PANDAR was conducted using the CRISPR/Cas9 system for PANDAR. The biological functions of PANDAR in GC cells were determined both in vitro and in vivo. Upregulated PANDAR in GC patients was positively correlated with increased tumour size, advanced TNM classification and a poor survival rate in GC patients. The ROC curves identified that the PANDAR level was a marker for discriminating the early-stage tumour group from the healthy group, the metastasis group from the non-metastasis group and the chemoresistance group from the chemosensitive group in GC patients. As a target, the CDKN1A gene was successfully downregulated by PANDAR. PANDAR controlled the transcription of the CDKN1A gene by competitively binding with p53 protein. In combination with a p53 activator (nutlin3), the knockout of PANDAR by CRISPR/Cas9 technology synergistically inhibited GC tumour growth in vivo. Our results suggest that the PANDAR is a powerful diagnostic and therapeutic marker for patients with GC and, combined with other chemotherapeutics, may have distinct antitumour effects.

Long non-coding PANDAR as a novel biomarker in human cancer: A systematic review

OBJECTIVES

Long non-coding RNAs (lncRNAs) are characterized as a group of RNAs that more than 200 nucleotides in length and have no protein-coding function. More and more evidences provided that lncRNAs serve as key molecules in the development of cancer. Deregulation of lncRNAs functions as either oncogenes or tumour suppressor genes in various diseases. Recently, increasing studies about PANDAR in cancer progression were reported. In our review, we will focus on the current research on the character of PANDAR include the clinical management, tumour progression and molecular mechanisms in human cancers.

MATERIALS AND METHODS

We summarize and analyze current studies concerning the biological functions and mechanisms of lncRNA PANDA in tumour development. The related studies were obtained through a systematic search of Pubmed.

RESULTS

PANDAR was a well-characterized oncogenic lncRNA and widely overexpressed in many tumours. PANDAR is upregulated in many types of cancer, including colorectal cancer, lung cancer, renal cell carcinoma, cholangiocarcinoma, osteosarcoma, thyroid cancer and other cancers. Upregulation of PANDAR was significantly associated with advanced tumour weights, TNM stage and overall survival. Furthermore, repressed of PANDAR would restrain proliferation, migration and invasion.

CONCLUSION

PANDAR may act as a powerful tumour biomarker for cancer diagnosis and treatment.