LncRNA KCNQ1OT1 Promotes Proliferation, Invasion and Metastasis of Prostate Cancer by Regulating miR-211-5p/CHI3L1 Pathway

The effects of glycemic index on prostate cancer progression in a xenograft mouse model

BACKGROUND

Previously, we found low-carbohydrate diets slowed prostate cancer (PC) growth and increased survival vs. a Western diet in mice, by inhibiting the insulin/IGF-1 axis. Thus, we tested whether modifying carbohydrate quality to lower glycemic index (GI) without changing quantity results in similar benefits as with reduced quantity.

METHODS

Male SCID mice injected with LAPC-4 cells were single-housed and randomized when their tumors reached 200 mm3 on average to a LoGI (48% carbohydrate kcal, from Hylon-VII) or HiGI Western diet (48% carbohydrate kcal, from sucrose). Body weight and tumor volume were measured weekly. Body composition was assessed 35 days after randomization. Blood glucose and serum insulin, IGF-1 and IGFBP3 were measured at study end when tumor volumes reached 800 mm3. We analyzed gene expression of mice tumors by RNA-sequencing and human tumors using the Prostate Cancer Transcriptome Atlas.

RESULTS

There were no significant differences in tumor volume (P > 0.05), tumor proliferation (P = 0.29), and overall survival (P = 0.15) between groups. At 35 days after randomization, the LoGI group had 30% lower body fat (P = 0.007) despite similar body weight (P = 0.58). At sacrifice, LoGI mice had smaller livers (P < 0.001) and lower glucose (P = 0.15), insulin (P = 0.11), IGF-1 (P = 0.07) and IGF-1:IGFBP3 ratio (P = 0.05), and higher IGFBP3 (P = 0.09) vs. HiGI, although none of these metabolic differences reached statistical significance. We observed differential gene expression and pathway enrichment in mice tumors by diet. The most upregulated and downregulated gene in the LoGI group showed expression patterns more closely resembling expression in human benign prostate tissue vs. PC.

CONCLUSIONS

In this single mouse xenograft model, consuming a low GI diet did not delay PC growth or survival vs. a high GI diet despite suggestions of decreased activation of the insulin/IGF-1 pathway. These data suggest that improving carbohydrate quality alone while consuming a high carbohydrate diet may not effectively slow PC growth.

Long non-coding RNA LOXL1-AS1: a potential biomarker and therapeutic target in human malignant tumors

Long non-coding RNAs (lncRNAs) are transcripts that contain more than 200 nucleotides. Despite their inability to code proteins, multiple studies have identified their important role in human cancer through different mechanisms. LncRNA lysyl oxidase like 1 antisense RNA 1 (LOXL1-AS1), a newly discovered lncRNA located on human chromosome 15q24.1, has recently been shown to be involved in the occurrence and progression of various malignancies, such as colorectal cancer, gastric cancer, hepatocellular carcinoma, prostate cancer, non-small cell lung cancer, ovarian cancer, cervical cancer, breast cancer, glioma, thymic carcinoma, pancreatic carcinoma. LOXL1-AS1 acts as competitive endogenous RNA (ceRNA) and via sponging various miRNAs, including miR-374b-5p, miR-21, miR-423-5p, miR-589-5p, miR-28-5p, miR-324-3p, miR-708-5p, miR-143-3p, miR-18b-5p, miR-761, miR-525-5p, miR-541-3p, miR-let-7a-5p, miR-3128, miR-3614-5p, miR-377-3p and miR-1224-5p to promote tumor cell proliferation, invasion, migration, apoptosis, cell cycle, and epithelial-mesenchymal transformation (EMT). In addition, LOXL1-AS1 is involved in the regulation of P13K/AKT and MAPK signaling pathways. This article reviews the current understanding of the biological function and clinical significance of LOXL1-AS1 in human cancers. These findings suggest that LOXL1-AS1 may be both a reliable biomarker and a potential therapeutic target for cancers.

The regulatory process and practical significance of non-coding RNA in the dissemination of prostate cancer to the skeletal system

Prostate cancer is a major contributor to male cancer-related mortality globally. It has a particular affinity for the skeletal system with metastasis to bones seriously impacting prognosis. The identification of prostate cancer biomarkers can significantly enhance diagnosis and patient monitoring. Research has found that cancer and metastases exhibit abnormal expression of numerous non-coding RNA. Some of these RNA facilitate prostate cancer bone metastasis by activating downstream signaling pathways, while others inhibit this process. Elucidating the functional processes of non-coding RNA in prostate cancer bone metastasis will likely lead to innovative treatment strategies for this malignant condition. In this review, the mechanistic role of the various RNA in prostate cancer is examined. Our goal is to provide a new avenue of approach to the diagnosis and treatment of bone metastasis in this cancer.

Circulating miRNAs and lncRNAs serve as biomarkers for early colorectal cancer diagnosis

BACKGROUND

Colorectal cancer (CRC), the third most prevalent and lethal disease, accounted for approximately 1.9 million new cases and claimed nearly 861,000 lives in 2018. It is imperative to develop a minimally invasive diagnostic technique for early identification of CRC. This would facilitate the selection of patient populations most suitable for clinical trials, monitoring disease progression, assessing treatment effectiveness, and enhancing overall patient care. Utilizing blood as a biomarker source is advantageous due to its minimal discomfort for patients, enabling better integration into clinical and follow-up trials. Recent findings indicate that long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) are detectable in the blood of cancer patients, proving crucial in diagnosing various malignancies.

METHODS

In this case-control study, we collected plasma samples from 30 patients diagnosed with colorectal cancer (CRC) and 30 healthy volunteers. Following RNA extraction, we measured the expression levels of specific biomolecules, including miR-410, miR-211, miR-139, miR-197, lncRNA UICLM, lncRNA FEZF1-AS1, miR-129, lncRNA CCAT1, lncRNA BBOX1-AS1, and lncRNA LINC00698, using real-time quantitative polymerase chain reaction (RT-qPCR). The obtained data underwent analysis using the Mann-Whitney test for non-parametric data and the T-test for parametric data.

RESULTS

The level of miR-410, miR-211, miR-139, miR-197, lncRNA UICLM, lncRNA FEZF1-AS1 were significantly higher in patients with CRC than healthy controls (p < .05). Meanwhile, the level of miR-129, lncRNA CCAT1, lncRNA BBOX1-AS1, and lncRNA LINC00698 were higher in healthy controls than in CRC patients (p < .05).

CONCLUSION

MicroRNA (miRNA) and long noncoding RNAs (lncRNAs) have recently emerged as detectable entities in the blood of cancer patients, playing crucial roles in diagnosing various malignancies. However, their specific relevance in the diagnosis of colorectal cancer (CRC) remains underexplored. This study aimed to investigate miRNA and lncRNA profiles in the plasma fraction of human blood to discern significant differences in content and expression levels between CRC patients and healthy individuals. Our cohort comprised 30 CRC patients and 30 healthy controls, with no statistically significant differences (p < 0.05) in age or gender observed between the two groups. Noteworthy is the uniqueness of our study, as we identified a panel of three significant microRNAs and one significant lncRNA, providing a more reliable prediction compared to existing molecular markers in diagnosing CRC. The four genes examined, including miR-211, miR-129, miR-197, and lncRNA UICLM, demonstrated impeccable results in terms of sensitivity and specificity, suggesting their potential candidacy for inclusion in diagnostic panels. Further validation in a larger statistical population is recommended to confirm the robustness of these genes as promising markers for colorectal cancer diagnosis.

A review on the role of KCNQ1OT1 lncRNA in human disorders

KCNQ1OT1 is an lncRNA located within KCNQ1 gene on chromosome 11p15.5. This lncRNAs participates in the pathogenesis of a diversity of cancers as well as non-cancerous conditions. In most types of cancers, KCNQ1OT1 is regarded as an oncogene. In a wide array of cancers, high level of KCNQ1OT1 is associated with lower overall survival time. This lncRNA has been found to adsorb a variety of miRNAs, namely miR-15a, miR-211-5p, hsa-miR-107, miR-145, miR-34a, miR-204-5p, miR-129-5p, miR-372-3p, miR-491-5p, miR-153, miR-185-5p, miR-124-3p, miR-211-5p, miR-149, miR-148a-3p, miR-140-5p, miR-125b-5p, miR-9, miR-329-3p, miR-760, miR-296-5p, miR-3666 and miR-129-5p, thus regulating the downstream targets of these miRNAs. In this manuscript, our attention is on this lncRNA and its biomolecular roles in human cancers and other disorders. KCNQ1OT1 plays significant roles in the tumorigenesis and may function as a prospective target for cancer therapy.

Long non-coding RNAs in cancer: multifaceted roles and potential targets for immunotherapy

Cancer remains a major global health concern with high mortality rates mainly due to late diagnosis and poor prognosis. Long non-coding RNAs (lncRNAs) are emerging as key regulators of gene expression in human cancer, functioning through various mechanisms including as competing endogenous RNAs (ceRNAs) and indirectly regulating miRNA expression. LncRNAs have been found to have both oncogenic and tumor-suppressive roles in cancer, with the former promoting cancer cell proliferation, migration, invasion, and poor prognosis. Recent research has shown that lncRNAs are expressed in various immune cells and are involved in cancer cell immune escape and the modulation of the tumor microenvironment, thus highlighting their potential as targets for cancer immunotherapy. Targeting lncRNAs in cancer or immune cells could enhance the anti-tumor immune response and improve cancer immunotherapy outcomes. However, further research is required to fully understand the functional roles of lncRNAs in cancer and the immune system and their potential as targets for cancer immunotherapy. This review offers a comprehensive examination of the multifaceted roles of lncRNAs in human cancers, with a focus on their potential as targets for cancer immunotherapy. By exploring the intricate mechanisms underlying lncRNA-mediated regulation of cancer cell proliferation, invasion, and immune evasion, we provide insights into the diverse therapeutic applications of these molecules.

LncRNA AP000842.3 Triggers the Malignant Progression of Prostate Cancer by Regulating Cuproptosis Related Gene NFAT5

OBJECTIVES

Prostate cancer (PRAD) is a highly malignant disease with poor prognosis, and its development is regulated by a complex network of genes and signaling pathways. LncRNAs and miRNAs have significant regulatory roles in PRAD through the ceRNA network. Cuproptosis is a unique form of programmed cell death that is involved in various signaling pathways and biological processes related to tumor development. Nuclear factor of activated T cells 5 (NFAT5), a transcription factor that activates T cells, has been implicated in cuproptosis. However, the regulatory mechanism by which NFAT5 is involved in the ceRNA network in PRAD remains unclear.

METHODS

Through bioinformatics analysis, we found the ceRNA axis that regulates cuproptosis. By performing ROS assay and copper ion concentration assay, we demonstrated that inhibiting NFAT5 can increase the sensitivity of PRAD to cuproptosis inducers. By using luciferase assay, we discovered that AP000842.3 acts as the ceRNA of miR-206 to regulate the expression of NFAT5.

RESULTS

In this study, we found that lncRNA AP000842.3, as a ceRNA of miR-206, was involved in the regulation of levels of the transcription factor NFAT5 associated with cuproptosis in PRAD. First, knocking down NFAT5 can increase the sensitivity of PRAD to cuproptosis inducers. Meanwhile, changes in the expression of AP000842.3 and miR-206 could affect the proliferation of PRAD by regulating NFAT5. Mechanistically, AP000842.3 acts as the ceRNA of miR-206 to regulate the expression of NFAT5. In addition, the effects of lncRNA AP000842.3 on malignant progression of PRAD and NFAT5 were partially dependent on miR-206.

CONCLUSION

Taken together, our study reveals a key ceRNA regulatory network in PRAD and can be regarded as a new potential target for PRAD diagnosis and treatment.

Biological role of long non-coding RNA KCNQ1OT1 in cancer progression

Long non-coding RNAs (lncRNAs) are a type of RNAs that are more than 200 nucleotides without protein-coding potential. In recent years, more and more attention has been paid to the role of lncRNAs in cancer pathogenesis. LncRNA KCNQ1 overlapping transcript 1 (KCNQ1OT1) is located on chromosome 11p15.5 with a total length of 91 kb and is highly expressed in various malignancies, which is closely related to tumor growth, lymph node metastasis, survival cycle and recurrence rate. In addition, KCNQ1OT1 is involved in the regulation of PI3K/AKT and Wnt/β-catenin signaling pathways. In this review, the mechanism and related progress of KCNQ1OT1 in different cancers were reviewed. It was found that KCNQ1OT1 can stabilize mRNA expression through sponging miRNA, which not only induced tumor cell proliferation, migration, invasion, drug resistance, epithelial-mesenchymal transition (EMT) and inhibited cell apoptosis in vitro, but also promoted tumor growth and metastasis in vivo. Therefore, as a new biomarker and therapeutic target, KCNQ1OT1 has broad prospects for the diagnosis and treatment of different cancers.

Potential Roles and Future Perspectives of Chitinase 3-like 1 in Macrophage Polarization and the Development of Diseases

Chitinase-3-like protein 1 (CHI3L1), a chitinase-like protein family member, is a secreted glycoprotein that mediates macrophage polarization, inflammation, apoptosis, angiogenesis, and carcinogenesis. Abnormal CHI3L1 expression has been associated with multiple metabolic and neurological disorders, including diabetes, atherosclerosis, and Alzheimer's disease. Aberrant CHI3L1 expression is also reportedly associated with tumor migration and metastasis, as well as contributions to immune escape, playing important roles in tumor progression. However, the physiological and pathophysiological roles of CHI3L1 in the development of metabolic and neurodegenerative diseases and cancer remain unclear. Understanding the polarization relationship between CHI3L1 and macrophages is crucial for disease progression. Recent research has uncovered the complex mechanisms of CHI3L1 in different diseases, highlighting its close association with macrophage functional polarization. In this article, we review recent findings regarding the various disease types and summarize the relationship between macrophages and CHI3L1. Furthermore, this article also provides a brief overview of the various mechanisms and inhibitors employed to inhibit CHI3L1 and disrupt its interaction with receptors. These endeavors highlight the pivotal roles of CHI3L1 and suggest therapeutic approaches targeting CHI3L1 in the development of metabolic diseases, neurodegenerative diseases, and cancers.

A thorough understanding of the role of lncRNA in prostate cancer pathogenesis; Current knowledge and future research directions

In the entire world, prostate cancer (PCa) is one of the most common and deadly cancers. Treatment failure is still common among patients, despite PCa diagnosis and treatment improvements. Inadequate early diagnostic markers and the emergence of resistance to conventional therapeutic approaches, particularly androgen-deprivation therapy, are the causes of this. Long non-coding RNAs (lncRNAs), as an essential group of regulatory molecules, have been reported to be dysregulated through prostate tumorigenesis and hold great promise as diagnostic targets. Besides, lncRNAs regulate the malignant features of PCa cells, such as proliferation, invasion, metastasis, and drug resistance. These multifunctional RNA molecules interact with other molecular effectors like miRNAs and transcription factors to modulate various signaling pathways, including AR signaling. This study aimed to compile new knowledge regarding the role of lncRNA through prostate tumorigenesis in terms of their effects on the various malignant characteristics of PCa cells; in light of these characteristics and the significant potential of lncRNAs as diagnostic and therapeutic targets for PCa. AVAILABILITY OF DATA AND MATERIALS: Not applicable.

Associations between KCNQ1OT1 genetic variation rs10766212 and susceptibility to colorectal cancer and clinical stage in a Chinese Han population

KCNQ1OT1 has been linked to the development and progression of colorectal cancer (CRC). As a result, functional polymorphisms in the KCNQ1OT1 gene may have a role in CRC formation and progression. The goal of this study was to see if the rs10766212 polymorphism on the KCNQ1OT1 gene was linked to CRC susceptibility and clinical stage in a Chinese Han population. The case-control research comprised a total of 576 CRC patients and 606 healthy controls. The genotype of the rs10766212 polymorphic locus was determined using the Sanger sequencing technique. We found that the KCNQ1OT1 rs10766212 polymorphism was not related to CRC susceptibility; however, it was connected with the clinical stage of CRC. Patients with CRC who had the rs10766212 T allele had a lower risk of stage III/IV tumors than those who had the rs10766212 C allele. Furthermore, CRC tissues with the rs10766212 CC genotype showed a significant negative connection between KCNQ1OT1 and hsa-miR-622 expression. The luciferase assay showed that the rs10766212 C allele might contribute to the adsorption of KCNQ1OT1 on hsa-miR-622. In conclusion, the rs10766212 polymorphism altering hsa-miR-622 binding is linked to the clinical stage of CRC and may serve as a biomarker for predicting CRC progression in the Chinese Han population. However, better-designed studies are still needed to confirm the current findings.

lncRNA EGFEM1P Drives the Progression of Papillary Thyroid Cancer by Regulating miR-6867-5p/CHI3L1 Axis

Long noncoding RNA (lncRNA), a subgroup of noncoding RNA with > 200 nt, plays critical roles in cancer progression. Here, we aimed to explore the detailed biological function of lncRNA EGFEM1P during papillary thyroid cancer (PTC) progression. RT-qPCR and Western blot were used to analyze the expression of lncRNA EGFEM1P, miR-6867-5p, and CHI3L1. CCK8, colony formation, and Transwell migration assays were undertaken to assess PTC cell proliferation and migration. A xenograft tumor mouse model was also used to establish tumor growth in vivo. Luciferase reporter and anti-AGO2 RNA immunoprecipitation (RIP) assays were used to clarify the interplay between miR-6867-5p and lncRNA EGFEM1P or CHI3L1. We found lncRNA EGFEM1P and CHI3L1 to be highly expressed in PTC tissues and cells, while miR-6867-5p expression decreases. Functionally, lncRNA EGFEM1P silence delays PTC cell proliferation and migration, and impairs tumorigenesis in vivo. LncRNA EGFEM1P targets miR-6867-5p, and CHI3L1 is a target gene of miR-6867-5p. LncRNA EGFEM1P silence decreases the pro-proliferation and pro-migration caused by the miR-6867-5p inhibitor in PTC cells, and CHI3L1 silence abrogates the pro-tumorigenic action resulting from the miR-6867-5p inhibitor in PTC cells. Our data showed that lncRNA EGFEM1P targeting of the miR-6867-5p/CHI3L1 axis drives PTC progression, suggesting lncRNA EGFEM1P as a therapeutically target for PTC.

Long non-coding RNAs in bone metastasis: progresses and perspectives as potential diagnostic and prognostic biomarkers

In a precision medicine perspective, among the biomarkers potentially useful for early diagnosis of cancers, as well as to define their prognosis and eventually to identify novel and more effective therapeutic targets, there are the long non-coding RNAs (lncRNAs). The term lncRNA identifies a class of non-coding RNA molecules involved in the regulation of gene expression that intervene at the transcriptional, post-transcriptional, and epigenetic level. Metastasis is a natural evolution of some malignant tumours, frequently encountered in patients with advanced cancers. Onset and development of metastasis represents a detrimental event that worsen the patient's prognosis by profoundly influencing the quality of life and is responsible for the ominous progression of the disease. Due to the peculiar environment and the biomechanical properties, bone is a preferential site for the secondary growth of breast, prostate and lung cancers. Unfortunately, only palliative and pain therapies are currently available for patients with bone metastases, while no effective and definitive treatments are available. The understanding of pathophysiological basis of bone metastasis formation and progression, as well as the improvement in the clinical management of the patient, are central but challenging topics in basic research and clinical practice. The identification of new molecular species that may have a role as early hallmarks of the metastatic process could open the door to the definition of new, and more effective, therapeutic and diagnostic approaches. Non-coding RNAs species and, particularly, lncRNAs are promising compounds in this setting, and their study may bring to the identification of relevant processes. In this review, we highlight the role of lncRNAs as emerging molecules in mediating the formation and development of bone metastases, as possible biomarkers for cancer diagnosis and prognosis, and as therapeutic targets to counteract cancer spread.

MiR-211 plays a dual role in cancer development: From tumor suppressor to tumor enhancer

Cancer is a general term for more than 100 unique malignancies in different organs of the body. Each cancer type and subtype has its own unique genetic, epigenetic, and cellular factors accountable for malignant progression and metastasis. Small non-coding RNAs called miRNAs target mRNAs and play a vital part in the pathogenesis of human diseases, specifically cancer. Recent investigations provided knowledge of the deregulation of miR-211 in various cancer types and disclosed that miR-211 has an oncogenic or tumor-suppressive impact on tumourigenesis and cancer development. Moreover, recent discoveries which clarify the essential functions of miR-211 might provide proof for its prognosis, diagnostic and therapeutic impact on cancer. Thereby, this review will discuss recent findings regarding miR-211 expression level, target genes, and mechanisms in different cancers. In addition, the most recent results that propose miR-211 usefulness as a noninvasive biomarker and therapeutic factor for the diagnosis and treatment of cancer will be explained.

The LINC00852/miR-29a-3p/JARID2 axis regulates the proliferation and invasion of prostate cancer cell

Long intergenic non-coding RNA 00852 (LINC00852) has been shown to promote the progression of many different cancers including prostate cancer. However, the involved mechanism in promoting the proliferation, migration and invasion of prostate cancer cells has not been reported. In this study, we found that LINC00852 was highly expressed in the tissue of prostate cancer using quantitative reverse transcription PCR (qRT-PCR). CCK-8 assay, colony formation experiment, Transwell migration and invasion experiments were performed to prove that the up-regulation of LINC00852 could promote the proliferation, migration and invasion of prostate cancer cells in vitro. Xenograft tumors experiments in nude mice confirmed that up-regulation of LINC00852 promoted the proliferation of prostate cancer cells in vivo. Bioinformatics predictions and dual-luciferase reporter gene assay showed that miR-29a-3p binds to the 3'-untranslated region of JARID2, and the enhancement of miR-29a-3p could reverse the effect of LINC00852 overexpression in vitro. Moreover, the results of qRT-PCR and western blot showed that LINC00852 could regulate the expression of JARID2 through miR-29a-3p induction. In summary, we demonstrated that LINC00852 played a key role in promoting the prostate cancer, and LINC00852/miR-29a-3p/JARID2 axis could be used as a target for prostate cancer treatment.

Upregulation of YKL-40 Promotes Metastatic Phenotype and Correlates with Poor Prognosis and Therapy Response in Patients with Colorectal Cancer

YKL-40 is a heparin- and chitin-binding glycoprotein that belongs to the family of glycosyl hydrolases but lacks enzymatic properties. It affects different (patho)physiological processes, including cancer. In different tumors, YKL-40 gene overexpression has been linked to higher cell proliferation, angiogenesis, and vasculogenic mimicry, migration, and invasion. Because, in colorectal cancer (CRC), the serological YKL-40 level may serve as a risk predictor and prognostic biomarker, we investigated the underlying mechanisms by which it may contribute to tumor progression and the clinical significance of its tissue expression in metastatic CRC. We demonstrated that high-YKL-40-expressing HCT116 and Caco2 cells showed increased motility, invasion, and proliferation. YKL-40 upregulation was associated with EMT signaling activation. In the AOM/DSS mouse model, as well as in tumors and sera from CRC patients, elevated YKL-40 levels correlated with high-grade tumors. In retrospective analyses of six independent cohorts of CRC patients, elevated YKL-40 expression correlated with shorter survival in patients with advanced CRC. Strikingly, high YKL-40 tissue levels showed a predictive value for a better response to cetuximab, even in patients with stage IV CRC and mutant KRAS, and worse sensitivity to oxaliplatin. Taken together, our findings establish that tissue YKL-40 overexpression enhances CRC metastatic potential, highlighting this gene as a novel prognostic candidate, a predictive biomarker for therapy response, and an attractive target for future therapy in CRC.

The effects of endosulfan on cell migration and invasion in prostate cancer cells via the KCNQ1OT1/miR-137-3p/PTP4A3 axis

Endosulfan belongs to persistent organic pollutants (POPs), closely related to an increased risk of prostate cancer (PCa). The existing evidence shows that lncRNAs compete with miRNAs for binding sites and contribute to the onset and progression of human malignancies. In this study we investigate how endosulfan promotes cell migration and invasion in DU145 and PC3 prostate cancer cells through epigenetic mechanism of lncRNA-miRNA regulation. Based on our past research we focused on PTP4A3 and constructed wild-type (WT) and mutant PTP4A3 plasmids for further analysis. Our results revealed that transfection of PTP4A3-WT can lead to changes in the expression of epithelial-mesenchymal transition (EMT) biomarkers and critical proteins in the TGF-β signaling pathway, and promote cell migration and invasion in PCa cells. Bioinformatics analysis shows that there were complementary sequences in PTP4A3 3'-UTR and KCNQ1OT1 3'-UTR to the seed sequence of hsa-miR-137-3p, and dual luciferase reporter assay indicates the potential binding capacity of miR-137-3p to 3'-UTR of PTP4A3 and KCNQ1OT1. We found that miR-137-3p mimic inhibited cell migration and invasion, as well as repressed alterations of EMT biomarkers and critical proteins in the TGF-β signaling pathway. Rescue experiment results revealed that co-transfection of miR-137-3p mimic and PTP4A3-WT plasmid reversed these changes following transfection with miR-137-3p mimic alone. We found that KCNQ1OT1 was predominantly distributed in the cytoplasm from a subcellular fractionation assay. Functionally, silencing of KCNQ1OT1 repressed cell migration and invasion, and caused alterations of EMT biomarkers and critical proteins in the TGF-β signaling pathway, which were all restored by co-transfection with anti-miR-137-3p or PTP4A3-WT plasmid. Furthermore, overexpression of miR-137-3p or silencing of KCNQ1OT1 dramatically rescued the effects of endosulfan on promoting cell migration and invasion. These findings suggest that endosulfan can indeed promote cell migration and invasion via the KCNQ1OT1/miR-137-3p/PTP4A3 axis in PCa cells.

Molecular Landscape of LncRNAs in Prostate Cancer: A focus on pathways and therapeutic targets for intervention

Background

One of the most malignant tumors in men is prostate cancer that is still incurable due to its heterogenous and progressive natures. Genetic and epigenetic changes play significant roles in its development. The RNA molecules with more than 200 nucleotides in length are known as lncRNAs and these epigenetic factors do not encode protein. They regulate gene expression at transcriptional, post-transcriptional and epigenetic levels. LncRNAs play vital biological functions in cells and in pathological events, hence their expression undergoes dysregulation.

Aim of review

The role of epigenetic alterations in prostate cancer development are emphasized here. Therefore, lncRNAs were chosen for this purpose and their expression level and interaction with other signaling networks in prostate cancer progression were examined.

Key scientific concepts of review

The aberrant expression of lncRNAs in prostate cancer has been well-documented and progression rate of tumor cells are regulated via affecting STAT3, NF-κB, Wnt, PI3K/Akt and PTEN, among other molecular pathways. Furthermore, lncRNAs regulate radio-resistance and chemo-resistance features of prostate tumor cells. Overexpression of tumor-promoting lncRNAs such as HOXD-AS1 and CCAT1 can result in drug resistance. Besides, lncRNAs can induce immune evasion of prostate cancer via upregulating PD-1. Pharmacological compounds such as quercetin and curcumin have been applied for targeting lncRNAs. Furthermore, siRNA tool can reduce expression of lncRNAs thereby suppressing prostate cancer progression. Prognosis and diagnosis of prostate tumor at clinical course can be evaluated by lncRNAs. The expression level of exosomal lncRNAs such as lncRNA-p21 can be investigated in serum of prostate cancer patients as a reliable biomarker.

SNHG3 could promote prostate cancer progression through reducing methionine dependence of PCa cells

In recent years, morbidity and mortality of prostate cancer (PCa) have increased dramatically, while mechanistic understanding of its onset and progression remains unmet. LncRNA SNHG3 has been proved to stimulate malignant progression of multiple cancers, whereas its functional mechanism in PCa needs to be deciphered. In this study, our analysis in the TCGA database revealed high SNHG3 expression in PCa tissue. Further analysis in starBase, TargetScan, and mirDIP databases identified the SNHG3/miR-152-3p/SLC7A11 regulatory axis. FISH was conducted to assess the distribution of SNHG3 in PCa tissue. Dual-luciferase reporter gene and RIP assays confirmed the relationship among the three objects. Next, qRT-PCR and western blot were conducted to measure expression levels of SNHG3, miR-152-3p, and SLC7A11. CCK-8, colony formation, Transwell, and flow cytometry were carried out to assess proliferation, migration, invasion, methionine dependence, apoptosis, and the cell cycle. It was noted that SNHG3 as a molecular sponge of miR-152-3p stimulated proliferation, migration, and invasion, restrained methionine dependence and apoptosis, and affected the cell cycle of PCa cells via targeting SLC7A11. Additionally, we constructed xenograft tumor models in nude mice and confirmed that knockdown of SNHG3 could restrain PCa tumor growth and elevate methionine dependence in vivo. In conclusion, our investigation improved understanding of the molecular mechanism of SNHG3 modulating PCa progression, thereby generating novel insights into clinical therapy for PCa.

Long Non-Coding RNAs at the Chromosomal Risk Loci Identified by Prostate and Breast Cancer GWAS

Long non-coding RNAs (lncRNAs) are emerging as key players in a variety of cellular processes. Deregulation of the lncRNAs has been implicated in prostate and breast cancers. Recently, germline genetic variations associated with cancer risk have been correlated with lncRNA expression and/or function. In addition, single nucleotide polymorphisms (SNPs) at well-characterized cancer-associated lncRNAs have been analyzed for their association with cancer risk. These SNPs may occur within the lncRNA transcripts or spanning regions that may alter the structure, function, and expression of these lncRNA molecules and contribute to cancer progression and may have potential as therapeutic targets for cancer treatment. Additionally, some of these lncRNA have a tissue-specific expression profile, suggesting them as biomarkers for specific cancers. In this review, we highlight some of the cancer risk-associated SNPs that modulated lncRNAs with a potential role in prostate and breast cancers and speculate on how these lncRNAs may contribute to cancer development.

Identification of Novel Biomarkers for Predicting Prognosis and Immunotherapy Response in Head and Neck Squamous Cell Carcinoma Based on ceRNA Network and Immune Infiltration Analysis

Objectives

Patients with head and neck squamous cell carcinoma (HNSCC) have poor prognosis and show poor responses to immune checkpoint (IC) inhibitor (ICI) therapy. Competing endogenous RNA (ceRNA) networks, tumor-infiltrating immune cells (TIICs), and ICIs may influence tumor prognosis and response rates to ICI therapy. This study is aimed at identifying prognostic and IC-related biomarkers and key TIIC signatures to improve prognosis and ICI therapy response in HNSCC patients.

Methods and Results

Ninety-five long noncoding RNAs (lncRNAs), microRNAs (miRNAs), and 1746 mRNAs were identified using three independent methods. We constructed a ceRNA network and estimated the proportions of 22 immune cell subtypes. Ten ceRNAs were related to prognosis according to Kaplan–Meier analysis. Two risk signatures based, respectively, on nine ceRNAs (ANLN, CFL2, ITGA5, KDELC1, KIF23, NFIA, PTX3, RELT, and TMC7) and three immune cell types (naïve B cells, neutrophils, and regulatory T cells) via univariate Cox regression, least absolute shrinkage and selection operator, and multivariate Cox regression analyses could accurately and independently predict the prognosis of HNSCC patients. Key mRNAs in the ceRNA network were significantly correlated with naïve B cells and regulatory T cells and with stage, grade, and immune and molecular subtype. Eight IC genes exhibited higher expression in tumor tissues and were correlated with eight key mRNAs in the ceRNA network in HNSCC patients with different HPV statuses according to coexpression and TIMER 2.0 analyses. Most drugs were effective in association with expression of these key signatures (ANLN, CFL2, ITGA5, KIF23, NFIA, PTX3, RELT, and TMC7) based on GSCALite analysis. The prognostic value of key biomarkers and associations between key ceRNAs and IC genes were validated using online databases. Eight key ceRNAs were confirmed to predict response to ICI in other cancers based on TIDE analysis.

Conclusions

We constructed two risk signatures to accurately predict prognosis in HNSCC. Key IC-related signatures may be associated with response to ICI therapy. Combinations of ICIs with inhibitors of eight key mRNAs may improve survival outcomes of HNSCC patients.

An effective N6-methyladenosine-related long non-coding RNA prognostic signature for predicting the prognosis of patients with bladder cancer

Background

Bladder cancer (BLCA) typically has a poor prognosis due to high relapse and metastasis rates. A growing body of evidence indicates that N6-methyladenosine (m6A) and long non-coding RNAs (lncRNAs) play crucial roles in the progression of BLCA and the treatment response of patients with BLCA. Therefore, we conducted a comprehensive RNA-seq analysis of BLCA using data from The Cancer Genome Atlas (TCGA) to establish an m6A-related lncRNA prognostic signature (m6A-RLPS) for BLCA.

Methods

Consensus clustering analysis was used to investigate clusters of BLCA patients with varying prognoses. The least absolute shrinkage and selection operator Cox regression were used to develop the m6A-RLPS. The ESTIMATE and CIBERSORT algorithms were used to evaluate the immune composition.

Results

A total of 745 m6A-related lncRNAs were identified using Pearson correlation analysis (|R| > 0.4, p < 0.001). Fifty-one prognostic m6A-related lncRNAs were screened using univariate Cox regression analysis. Through consensus clustering analysis, patients were divided into two clusters (clusters 1 and 2) with different overall survival rates and tumor stages based on the differential expression of the lncRNAs. Enrichment analysis demonstrated that terms related to tumor biological processes and immune-related activities were increased in patient cluster 2, which was more likely to exhibit low survival rates. Nine m6A-related prognostic lncRNAs were finally determined and subsequently used to construct the m6A-RLPS, which was verified to be an independent predictor of prognosis using univariate and multivariate Cox regression analyses. Further, a nomogram based on age, tumor stage, and the m6A-RLPS was generated and showed high accuracy and reliability with respect to predicting the survival outcomes of BLCA patients. The prognostic signature was found to be strongly correlated to tumor-infiltrating immune cells and immune checkpoint expression.

Conclusions

We established a novel m6A-RLPS with a favorable prognostic value for patients with BLCA. We believe that this prognostic signature can provide new insights into the tumorigenesis of BLCA and predict the treatment response in patients with BLCA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08981-4.

KCNQ1OT1: An Oncogenic Long Noncoding RNA

Long noncoding RNAs (lncRNAs) are transcripts greater than 200 nucleotides that do not code for proteins but regulate gene expression. Recent studies indicate that lncRNAs are involved in the modulation of biological functions in human disease. KCNQ1 Opposite Strand/Antisense Transcript 1 (KCNQ1OT1) encodes a lncRNA from the opposite strand of KCNQ1 in the CDKN1C/KCNQ1OT1 cluster that is reported to play a vital role in the development and progression of cancer. KCNQ1OT1 regulates cancer cell proliferation, cell cycle, migration and invasion, metastasis, glucose metabolism, and immune evasion. The aberrant expression of KCNQ1OT1 in cancer patients is associated with poor prognosis and decreased survival. This review summarizes recent literature related to the biological functions and molecular mechanisms of KCNQ1OT1 in various human cancers, including colorectal, bladder, breast, oral, melanoma, osteosarcoma, lung, glioma, ovarian, liver, acute myeloid leukemia, prostate, and gastric. We also discuss the role of KCNQ1OT1 as a promising diagnostic biomarker and a novel therapeutic target in human cancers.

LncRNA PART1/miR-185-5p/RUNX3 feedback loop modulates osteogenic differentiation of bone marrow mesenchymal stem cells

BACKGROUND

Osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBMSCs) is essential for bone formation, and its dysfunction is reported to be associated with osteoporosis (OP). Recent researches have determined that lncRNA PART1 participates in the pathogenesis of multiple diseases. However, its role in modulating osteogenic differentiation of hBMSCs is unclear.

METHODS

PART1, miR-185-5p, and RUNX3 levels were assessed via RT-qPCR. The protein levels of OCN, OSN, and COL1A1 were measured by western blotting. The osteoblastic phenotype was evaluated via ALP activity and ARS staining. The relationship between miR-185-5p and PART1 or RUNX3 was validated by luciferase reporter, RIP assays.

RESULTS

PART1 and RUNX3 expression were enhanced during hBMSC osteogenic differentiation. PART1 deletion decreased OCN, OSN, and COL1A1 levels and weakened ALP activity, but promoted the apoptosis of hBMSCs. Moreover, PART1 served as a ceRNA to influence the RUNX3 level via targeting miR-185-5p. In addition, RUNX3 was verified to activate the transcription of PART1 in hBMSCs. Finally, rescue assays indicated that suppression of miR-185-5p or addition of RUNX3 partially abolished the effects of PART1 knockdown on the levels of OCN, OSX, and COL1A1 levels, ALP activity, and apoptosis.

CONCLUSION

Our study elaborated that PART1/miR-185-5p/RUNX3 feedback contributed to osteogenic differentiation and inhibited the hBMSCs apoptosis, suggesting that PART1 might be a novel target for OP treatment.

The lncRNA OGFRP1/miR-149-5p/IL-6 axis regulates prostate cancer chemoresistance

BACKGROUND

The long non-coding RNA (lncRNA) OGFRP1 has been found to promote malignancy in prostate cancer (PC) and other cancer types. How this lncRNA functions in the regulation of PC chemoresistance, however, is poorly defined.

METHODS

qRT-PCR was employed to measure OGFRP1, miR-149-5p, and IL-6 expression in PC tissues and cells. IC50 values for paclitaxel and docetaxel in PC cells were assessed via a CCK-8 assay approach. Putative miR-149-5p binding targets were identified and validated through bioinformatics assays and luciferase reporter assays, respectively. The impact of OGFRP1 on PC chemoresistance in vivo was validated using a xenograft model system.

RESULTS

Docetaxel-resistant PC (PC/DR) cells and tissues exhibited reduced OGFRP1 expression and increased miR-149-5p expression. Knocking down OGFRP1 augmented the sensitivity of these PC cells to docetaxel and paclitaxel in vitro and in vivo. Mechanistically, OGFRP1 was found to bind and sequester miR-149-5p within PC/DR cells, thereby indirectly regulating IL-6 expression. Consistent with this model, the overexpression of IL-6 reversed the OGFRP1 knockdown-mediated reductions in docetaxel and paclitaxel IC50 values for these PC cells.

CONCLUSIONS

OGFRP1 can sequester miR-149-5p, thereby indirectly promoting IL-6 upregulation and thereby promoting chemoresistance in PC cells. This OGFRP1/miR-149-5p/IL-6 axis may thus be a promising target for therapeutic efforts aimed at PC chemosensitization and treatment.