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

Expression and clinical significance of lncRNA PART1 in patients with unexplained recurrent pregnancy loss

PURPOSE

Previous studies have reported the involvement of long noncoding RNAs (lncRNAs) in reproductive diseases via the regulation of target genes. This study aimed to determine whether lnc-prostate androgen-regulated transcript 1 (lnc-PART1)could be used as a biomarker of unexplained recurrent pregnancy loss (URPL) and a possible predictor of poor pregnancy outcomes in women with URPL.

MATERIALS AND METHODS

Sixty patients with URPL and 15 healthy women were included in this study. PART1 expression was detected in plasma and endometrial tissues using a quantitative reverse transcription polymerase chain reaction. Logistic regression and receiver operating characteristic curve analyses were performed to analyze the association between PART1 expression and pregnancy outcomes in women with URPL.

RESULTS

The expression of PART1transcript variant 2 was significantly up-regulated in the endometrial specimens from patients with URPL compared to control tissues. High tissue expression levels of PART1transcript variant 2 were associated with poor pregnancy outcomes in women with URPL, indicating that it could serve as a potential risk factor. Additionally, PART1 could serve as a potential risk factor for adverse pregnancy outcomes in patients with URPL (OR = 4.374; 95% CI = 1.052-18.189; p = .042).

CONCLUSION

lncRNA PART1 transcript variant 2 was highly expressed in patients with URPL. Therefore, it is important to conduct in-depth studies on the relationship between PART1 expression and URPL.

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.

Participation of TLRs in cancer immunopathogenesis and drug resistance via interacting with immunological and/or non-immunological signaling pathways as well as lncRNAs

Toll-like receptors (TLRs) have a convoluted role in cancer even though they are crucial to the immune system. By bridging the innate immune system and cancer, TLRs have a very complex impact on the formation of tumors and the effectiveness of anti-cancer treatments. TLR signaling links the innate and adaptive immune systems and initiates direct pathogen eradication. In cancer immunopathogenesis and treatment resistance, long non-coding RNAs (lncRNAs) modify TLR signaling linkages with immunological and non-immunological pathways. We identified lncRNAs that positively and negatively control TLR signaling, impacting immunological response and drug sensitivity. These results highlight the complex interactions between long non-coding RNAs and TLRs that influence the start of cancer and its response to treatment. Targeting specific lncRNAs is a practical way to control TLR signaling and perhaps enhance anti-tumor immunity while overcoming medication resistance. We provide a framework for developing novel immunotherapeutic regimens and customized medicine approaches for cancer treatment. The exact mechanisms by which lncRNAs regulate TLR signaling pathways should be defined by further research, and these findings should be validated in clinical situations. This finding makes future research of lncRNA-based drugs in combination with existing cancer treatments feasible.

Roles of Long Noncoding RNA in Prostate Cancer Pathogenesis

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

PART1 facilitates tumorigenesis and inhibits ferroptosis by regulating the miR-490-3p/SLC7A11 axis in hepatocellular carcinoma

BACKGROUND

Ferroptosis is associated with cancer progression and has a promising application for treating hepatocellular carcinoma (HCC). Long non-coding RNA (lncRNA) participates widely in the regulation of ferroptosis, but the key lncRNA regulators implicated in ferroptosis and their molecular mechanisms remain to be identified.

METHODS

Bioinformatic analysis was performed in R based on The Cancer Genome Atlas Program (TCGA) public database. The relative expression of genes was detected by real-time quantitative PCR. Cell viability was assessed by the CCK8 assay. The cell cycle and apoptosis were detected by flow cytometry. Migration and invasion of HCC cells were detected by Transwell assay and wound healing assay. Expression of relevant proteins was detected by Western blotting. A dual-luciferase reporter assay was used to detect interactions between PART1 (or SLC7A11) and miR-490-3p.

RESULTS

The PART1/miR-490-3p/SLC7A11 axis was identified as a potential regulatory pathway of ferroptosis in HCC. PART1 silencing reduced HCC cell proliferation, migration, and metastasis and promoted apoptosis and erastin-reduced ferroptosis. Further investigation revealed that PART1 acted as a competitive endogenous RNA (ceRNA) for miR-490-3p to enhance SLC7A11 expression. Overexpression of miR-490-3p downregulated the expression of SLC7A11, inhibiting the proliferation, invasion, and metastasis of HCC cells while promoting apoptosis and erastin-induced ferroptosis. Knockdown of PART1 in HCC cells significantly improved the sensitivity of HCC cells to sorafenib.

CONCLUSION

Our results revealed that the PART1/miR-490-3p/SLC7A11 axis enhances HCC cell malignancy and suppresses ferroptosis, which provides a new perspective for understanding of the function of long chain non-coding RNAs in HCC. The PART1/miR-490-3p/SLC7A11 axis may be target for improving sorafenib sensitivity in HCC.

LncRNA PART1 promotes malignant biological behaviours associated with head and neck cancer cells via synergistic action with FUT6

The aim of this study was to determine the role of lncRNA PART1 and downstream FUT6 in tumorigenesis and progression of head and neck cancer (HNC). Bioinformatics analysis and qRT-PCR revealed that lncRNA PART1 was expressed at low levels in HNC patients. The proliferation, apoptosis, migration and flow cytometry results showed that low expression of lncRNA PART1 inhibited apoptosis and promoted HNC cell migration and proliferation. In addition, animal experiments have also shown that low expression of lncRNA PART1 can promote tumor growth. LncRNA PART1 overexpression promoted apoptosis and inhibited HNC cell migration and proliferation. Through bioinformatics analysis, FUT6 was found to be expressed at low levels in HNC and to be correlated with patient survival. Immunohistochemical and qRT-PCR results revealed that FUT6 was underexpressed in tumour tissues and HNC cells. Cell and animal experiments showed that overexpression of FUT6 could inhibit tumour proliferation and migration. Bioinformatics analysis revealed that lncRNA PART1 was positively correlated with FUT6. By qRT-PCR and western blot, we observed that after knockdown of lncRNA PART1, both the mRNA and protein expression levels of FUT6 were reduced. The above results indicated that lncRNA PART1 and FUT6 play an important role in HNC, and that lncRNA PART1 affected the development of tumor by downstream FUT6.

LncRNAs in Immune and Stromal Cells Remodel Phenotype of Cancer Cell and Tumor Microenvironment

Emerging studies suggest that long non-coding RNAs (lncRNAs) participate in the mutual regulation of cells in tumor microenvironment, thereby affecting the anti-tumor immune activity of immune cells. Additionally, the intracellular pathways mediated by lncRNAs can affect the expression of immune checkpoints or change the cell functions, including cytokines secretion, of immune and stromal cells in tumor microenvironment, which further influences cancer patients' prognosis and treatment response. With the in-depth research, lncRNAs have shown great potency as a new immunotherapy target and predict immunotherapy response. The research on lncRNAs provides us with a new insight into developing new immunotherapy drugs and predicting the outcome of immunotherapy. With development of RNA sequencing technology, amounts of lncRNAs were found to be dysregulated in immune and stromal cells rather than tumor cells. These lncRNAs function through ceRNA network or regulating transcript factor activity, thus leading abnormal differentiation and activation of immune and stromal cells. Here, we review the function of lncRNAs in the immune microenvironment and focus on the alteration of lncRNAs in immune and stromal cells, and discuss how these alterations affect tumor growth, metastasis and treatment response.

Tumor-infiltrating macrophage associated lncRNA signature in cutaneous melanoma: implications for diagnosis, prognosis, and immunotherapy

Along with the increasing knowledge of long noncoding RNA, the interaction between the long noncoding RNA (lncRNA) and tumor immune infiltration is increasingly valued. However, there is a lack of understanding of correlation between regulation of specific lncRNAs and tumor-infiltrating macrophages within melanoma. In this research, a macrophage associated lncRNA signature was identified by multiple machine learning algorithms and the robust and effectiveness of signature also validated in other independent datasets. The signature contained six specific lncRNAs (PART1, LINC00968, LINC00954, LINC00944, LINC00518 and C20orf197) was constructed, which could diagnose melanoma and predict the prognosis of patients. Moreover, our signature achieves higher accuracy than the previous well-established markers and regarded as an independent prognostic indicator. The pathway enrichment revealed that these lncRNAs were closely correlated with many immune processes. In addition, the signature was associated with different immune microenvironment and applied to predict response of immune checkpoint inhibitor therapy (low risk of patients well respond to anti-PD-1 therapy and high risk is insensitive to anti-CTLA-4 therapy). Therefore, our finding supplies a more accuracy and effective lncRNA signature for tumor-infiltrating macrophages targeting treatment approaches and affords a new clinical application for predicting the response of immunotherapies in melanomas.

Urinary PART1 and PLA2R1 Could Potentially Serve as Diagnostic Markers for Diabetic Kidney Disease Patients

Background

Diabetic kidney disease (DKD) is a chronic renal disease which could eventually develop into renal failure. Though albuminuria and estimated glomerular filtration rate (eGFR) are helpful for the diagnosis of DKD, the lack of specific biomarkers reduces the efficiency of therapeutic interventions.

Methods

Based on bulk-seq of 56 urine samples collected at different time points (including 11 acquired from DKD patients and 11 from healthy controls), in corporation of scRNA-seq data of urine samples and snRNA-seq data of renal punctures from DKD patients (retrieved from NCBI GEO Omnibus), urine-kidney specific genes were identified by Multiple Biological Information methods.

Results

Forty urine-kidney specific genes/differentially expressed genes (DEGs) were identified to be highly related to kidney injury and proteinuria for the DKD patients. Most of these genes participate in regulating glucagon and apoptosis, among which, urinary PART1 (mainly derived from distal tubular cells) and PLA2R1 (podocyte cell surface marker) could be used together for the early diagnosis of DKD. Moreover, urinary PART1 was significantly associated with multiple clinical indicators, and remained stable over time in urine.

Conclusion

Urinary PART1 and PLA2R1 could be shed lights on the discovery and development of non-invasive diagnostic method for DKD, especially in early stages.

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.

Identification of androgen response-related lncRNAs in prostate cancer

BACKGROUND

Long noncoding RNAs (lncRNAs) are RNA molecules with over 200 nucleotides that do not code for proteins, but are known to be widely expressed and have key roles in gene regulation and cellular functions. They are also found to be involved in the onset and development of various cancers, including prostate cancer (PCa). Since PCa are commonly driven by androgen regulated signaling, mainly stimulated pathways, identification and determining the influence of lncRNAs in androgen response is useful and necessary. LncRNAs regulated by the androgen receptor (AR) can serve as potential biomarkers for PCa. In the present study, gene expression data analysis were performed to distinguish lncRNAs related to the androgen response pathway.

METHODS AND RESULTS

We used publicly available RNA-sequencing and ChIP-seq data to identify lncRNAs that are associated with the androgen response pathway. Using Universal Correlation Coefficient (UCC) and Pearson Correlation Coefficient (PCC) analyses, we found 15 lncRNAs that have (a) highly correlated expression with androgen response genes in PCa and are (b) differentially expressed in the setting of treatment with an androgen agonist as well as antagonist compared to controls. Using publicly available ChIP-seq data, we investigated the role of androgen/AR axis in regulating expression of these lncRNAs. We observed AR binding in the promoter regions of 5 lncRNAs (MIR99AHG, DUBR, DRAIC, PVT1, and COLCA1), showing the direct influence of AR on their expression and highlighting their association with the androgen response pathway.

CONCLUSION

By utilizing publicly available multiomics data and by employing in silico methods, we identified five candidate lncRNAs that are involved in the androgen response pathway. These lncRNAs should be investigated as potential biomarkers for PCa.

Emerging RNA-Based Therapeutic and Diagnostic Options: Recent Advances and Future Challenges in Genitourinary Cancers

Renal cell carcinoma, bladder cancer, and prostate cancer are the most widespread genitourinary tumors. Their treatment and diagnosis have significantly evolved over recent years, due to an increasing understanding of oncogenic factors and the molecular mechanisms involved. Using sophisticated genome sequencing technologies, the non-coding RNAs, such as microRNAs, long non-coding RNAs, and circular RNAs, have all been implicated in the occurrence and progression of genitourinary cancers. Interestingly, DNA, protein, and RNA interactions with lncRNAs and other biological macromolecules drive some of these cancer phenotypes. Studies on the molecular mechanisms of lncRNAs have identified new functional markers that could be potentially useful as biomarkers for effective diagnosis and/or as targets for therapeutic intervention. This review focuses on the mechanisms underlying abnormal lncRNA expression in genitourinary tumors and discusses their role in diagnostics, prognosis, and treatment.

A review on the role of long non-coding RNA prostate androgen-regulated transcript 1 (PART1) in the etiology of different disorders

LncRNA prostate androgen-regulated transcript 1 (PART1) is an important lncRNA in the carcinogenesis whose role has been firstly unraveled in prostate cancer. Expression of this lncRNA is activated by androgen in prostate cancer cells. In addition, this lncRNA has a role in the pathogenesis intervertebral disc degeneration, myocardial ischemia-reperfusion injury, osteoarthritis, osteoporosis and Parkinson's disease. Diagnostic role of PART1 has been assessed in some types of cancers. Moreover, dysregulation of PART1 expression is regarded as a prognostic factor in a variety of cancers. The current review provides a concise but comprehensive summary of the role of PART1 in different cancers and non-malignant disorders.

Mitochondrial Aldehyde Dehydrogenase 2 Represents a Potential Biomarker of Biochemical Recurrence in Prostate Cancer Patients

BACKGROUND

We aimed to explore the role of mitochondrial aldehyde dehydrogenase 2 (ALDH2) in prostate cancer (PCa) patients and provide insights into the tumor immune microenvironment (TME) for those patients undergoing radical radiotherapy.

METHODS

We performed all analyses using R version 3.6.3 and its suitable packages. Cytoscape 3.8.2 was used to establish network of competing endogenous RNAs (ceRNAs).

RESULTS

Downregulation of ADLH2 was significantly associated with higher risk of BCR-free survival (HR: 0.40, 95%CI: 0.24-0.68, p = 0.001) and metastasis-free survival (HR: 0.21, 95%CI: 0.09-0.49, p = 0.002). Additionally, ALDH2 repression contributed to significantly shorter BCR-free survival in the TCGA database (HR: 0.55, 95%CI: 0.33-0.93, p = 0.027). For immune checkpoints, patients that expressed a higher level of CD96 had a higher risk of BCR than their counterparts (HR: 1.79, 95%CI: 1.06-3.03, p = 0.032), as well as NRP1 (HR: 2.18, 95%CI: 1.29-3.69, p = 0.005). In terms of the TME parameters, the spearman analysis showed that ALDH was positively associated with B cells (r: 0.13), CD8+ T cells (r: 0.19), neutrophils (r: 0.13), and macrophages (r: 0.17). Patients with higher score of neutrophils (HR: 1.75, 95%CI: 1.03-2.95, p = 0.038), immune score (HR: 1.92, 95%CI: 1.14-3.25, p = 0.017), stromal score (HR: 2.52, 95%CI: 1.49-4.26, p = 0.001), and estimate score (HR: 1.81, 95%CI: 1.07-3.06, p = 0.028) had higher risk of BCR than their counterparts. Our ceRNA network found that PART1 might regulate the expression of ALDH via has-miR-578 and has-miR-6833-3p. Besides, PHA-793887, PI-103, and piperlongumine had better correlations with ALDH2.

CONCLUSIONS

We found that ALDH2 might serve as a potential biomarker predicting biochemical recurrence for PCa patients.

Long non‑coding RNA PART1: dual role in cancer

Increasing evidence has shown that long non-coding RNAs (lncRNAs), which are non-coding endogenous single-stranded RNAs, play an essential role in various physiological and pathological processes through transcriptional interference, post-transcriptional regulation, and epigenetic modification. Moreover, lncRNAs, as oncogenes or tumor suppressor genes, play an important role in the occurrence and development of human cancers. Prostate androgen-regulated transcript 1 (PART1) was initially identified as a carcinogenic lncRNA in prostate adenomas. The upregulated expression of PART1 plays a tumor-promoting role in liver, prostate, lung cancers, and other tumors. In contrast, the expression of PART1 is downregulated in esophageal squamous cell carcinoma, glioma, and other tumors, which may inhibit the tumor. PART1 plays a dual role in cancer and regulates cell proliferation, apoptosis, invasion, and metastasis through a variety of potential mechanisms. These findings suggest that PART1 is a promising tumor biomarker and therapeutic target. This article reviews the biological functions, related mechanisms, and potential clinical significance of PART1 in a variety of human cancers.

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.

Construction and validation of N6-methyladenosine long non-coding RNAs signature of prognostic value for early biochemical recurrence of prostate cancer

PURPOSE

Early biochemical recurrence (eBCR) indicated a high risk for potential recurrence and metastasis in prostate cancer. The N6-methyladenosine (m6A) methylation modification played an important role in prostate cancer progression. This study aimed to develop a m6A lncRNA signature to accurately predict eBCR in prostate cancer.

METHODS

Pearson correlation analysis was first conducted to explore m6A lncRNAs and univariate Cox regression analysis was further performed to identify m6A lncRNAs of prognostic roles for predicting eBCR in prostate cancer. The m6A lncRNA signature was constructed by least absolute shrinkage and selection operator analysis (LASSO) in training cohort and further validated in test cohort. Furthermore, half maximal inhibitory concentration (IC50) values were utilized to explore potential effective drugs for high-risk group in this study.

RESULTS

Five hundred and thirty-eighth m6A lncRNAs were searched out through Pearson correlation analysis and 25 out of 538 m6A lncRNAs were identified to pose prediction roles for eBCR in prostate cancers. An m6A lncRNA signature including 5 lncRNAs was successfully built in training cohort. The high-risk group derived from m6A lncRNA signature could efficiently predict eBCR occurrence in both training (p < 0.001) and test cohort (p = 0.002). ROC analysis also confirmed that lncRNA signature in this study posed more accurate prediction roles for eBCR occurrence when compared with PSA, TNM stages and Gleason scores. Drug sensitivity analysis further discovered that various drugs could be potentially utilized to treat high-risk samples in this study.

CONCLUSIONS

The m6A lncRNA signature in this study could be utilized to efficiently predict eBCR occurrence, various clinical characteristic and immune microenvironment for prostate cancer.

Identification of LOC101927355 as a Novel Biomarker for Preeclampsia

Preeclampsia, a disorder with a heterogeneous physiopathology, can be attributed to maternal, fetal, and/or placental factors. Long non-coding RNAs (lncRNAs) refer to a class of non-coding RNAs, the essential regulators of biological processes; their differential expression has been associated with the pathogenesis of multiple diseases. The study aimed to identify lncRNAs, expressed in the placentas and plasma of patients who presented with preeclampsia, as potential putative biomarkers of the disease. In silico analysis was performed to determine lncRNAs differentially expressed in the placentas of patients with preeclampsia, using a previously published RNA-Seq dataset. Seven placentas and maternal plasma samples collected at delivery from preterm preeclamptic patients (≤37 gestational weeks of gestation), and controls were used to validate the expression of lncRNAs by qRT-PCR. Six lncRNAs were validated and differentially expressed (p < 0.05) in the preeclampsia and control placentas: UCA1 and HCG4 were found upregulated, and LOC101927355, LINC00551, PART1, and NRAD1 downregulated. Two of these lncRNAs, HCG4 and LOC101927355, were also detected in maternal plasma, the latter showing a significant decrease (p = 0.03) in preeclamptic patients compared to the control group. In silico analyses showed the cytoplasmic location of LOC101927355, which suggests a role in post-transcriptional gene regulation. The detection of LOC101927355 in the placenta and plasma opens new possibilities for understanding the pathogenesis of preeclampsia and for its potential use as a biomarker.

lncRNA MNX1‑AS1 promotes prostate cancer progression through regulating miR‑2113/MDM2 axis

A growing number of dysregulated long non-coding (lnc)RNAs have been verified to serve an essential role in human prostate cancer. However, the underlying mechanisms of lncRNA MNX1 Antisense RNA 1 (MNX1-AS1) in prostate cancer has not been explored. Therefore, the present study aimed to explore the function of MNX1-AS1 in prostate cancer tumorigenesis and investigate the in-depth mechanism. The expression of MNX1-AS1, microRNA (miR)-2113 and murine double min 2 (MDM2) in prostate cancer tissues and corresponding normal tissues were assessed by reverse transcription-quantitative PCR. The protein expression levels of MDM2 were detected by western blotting. LNCaP and PC-3 cells were transfected with short hairpin (sh)-MNX1-AS1, miR-2113 mimics, miR-2113 inhibitor and pCDH-MDM2 vector using Lipofectamine^® 3000. Cell proliferation, migration and invasion abilities were assessed by CCK-8 assay, colony formation and Transwell assay, respectively. Dual luciferase reporter assay was carried out to confirm the putative targets of MNX1-AS1 and miR-2113. Tumor formation experiment in nude mice was applied to evaluate the tumor growth effect of MNX1-AS1 in vivo. The expression of MNX1-AS1 was significantly upregulated in the prostate cancer tissues and cell lines. MNX1-AS1 knockdown suppressed the abilities of cell viability and migration and invasion in vitro and inhibited tumor growth in vivo. Additionally, luciferase reporter assay revealed that MNX1-AS1 could target miR-2113 and negatively interacted with miR-2113 in prostate cancer cells. miR-2113 directly targeted to MDM2 and negatively modulated the expression of MDM2. Rescue assays suggested that the viability, migration and invasion of impaired cells triggered by transfection with sh-MNX1-AS1 alone could be recovered by co-transfection with sh-MNX1-AS1 + miR-2113 inhibitor or sh-MNX1-AS1 + pCDH- MDM2 vector. The present study demonstrated that MNX1-AS1 promoted prostate cancer progression through regulating miR-2113/ MDM2 axis.

Tumor-derived extracellular vesicles containing long noncoding RNA PART1 exert oncogenic effect in hepatocellular carcinoma by polarizing macrophages into M2

AIM

We explored whether tumor-derived extracellular vesicles (EVs) could deliver long noncoding RNA (lncRNA) PART1 into macrophage to orchestrate macrophage polarization in the progression of hepatocellular carcinoma (HCC).

METHOD

The expression patterns of PART1, microRNA (miR)-372-3p and TLR4 were detected by RT-qPCR in the HCC tissues and HCC cells. PART1 was silenced or overexpressed in HCC cells to assess its effects on the HCC cell process. EVs were isolated from PART1-overexpressed HCC cells, and co-cultured with macrophages, and gain- and loss-of-function assays were implemented in macrophages to evaluate their role in macrophage polarization. Relationship among PART1, miR-372-3p, and TLR4 was evaluated. Effect of EV-PART1 on tumorigenicity in vivo was detected by subcutaneous tumorigenicity test in nude mice.

RESULT

PART1 and TLR4 were upregulated while miR-372-3p was downregulated in HCC tissues and cells. PART1 increased HCC cell proliferation, migration, invasion, and EMT. Mechanistically, PART1 bound to miR-372-3p to downregulate its expression, whereas TLR4 was negatively targeted by miR-372-3p in the macrophages. EVs containing PART1, TLR4 overexpression, or miR-372-3p inhibition induced M2 polarization of macrophages. Also, EVs containing PART1 promoted M2 polarization of macrophages and the occurrence of HCC by affecting miR-372-3p/TLR4 axis.

CONCLUSION

HCC cell-derived EVs might up-regulate TLR4 by inhibiting miR-372-3p via PART1 delivery to promote macrophage M2 polarization in HCC.

Prognostic Value of Long Noncoding RNA SNHG11 in Patients with Prostate Cancer

The present study was aimed to explore the prognostic value of long noncoding RNA SNHG11 in prostate cancer, study its expression, and assess its effect on tumor progression. One hundred and twenty prostate cancer patients and 45 cases of benign prostate hyperplasia (BPH) patients were collected. RT-qPCR was used to test the expression of SNHG11 in prostate cancer and BPH tissues, as well as in cell lines. Kaplan-Meier survival analysis and Cox regression assays were introduced to evaluate the prognostic meaning of SNHG11 in prostate cancer. The CCK-8 assays were performed to explore the effect of SNHG11 on prostate cancer cell proliferation, and a Transwell assay was conducted to access the influence of SNHG11 on prostate cancer cell migration and invasion. SNHG11 expression level was upregulated both in prostate cancer tissues and cell lines. Overexpression of SNHG11 was significantly associated with Gleason score, clinical T stage, surgical margin status, and lymph node metastasis. Patients with high SNHG11 expression levels led to a shorter overall survival time and biochemical recurrence-free survival when compared with those of low expression levels. Multivariate Cox regression results suggested that SNHG11 has the potential to act as a prognostic marker for prostate cancer patients. Knockdown of SNHG11 suppressed 22RV1 cell proliferation, migration, and invasion. In conclusion, SNHG11 is upregulated in prostate cancer patients and predicts an unfavorable prognosis for prostate cancer patients. Its knockdown can weaken prostate cancer cell metastasis and growth in vitro.

Emerging Roles of lncRNAs Regulating RNA-Mediated Type-I Interferon Signaling Pathway

The type-I interferon (IFN-I) signaling pathway plays pivot roles in defending against pathogen invasion. Exogenous ssRNA and dsRNA could be immunogenic. RNA-mediated IFN signaling is extensively studied in the field. The incorrect functioning of this pathway leads to either autoimmune diseases or suffering from microorganism invasion. From the discrimination of “self” and “non-self” molecules by receptors to the fine-tune modulations in downstream cascades, all steps are under the surveillance featured by complex feedbacks and regulators. Studies in recent years highlighted the emerging roles of long noncoding RNAs (lncRNAs) as a reservoir for signaling regulation. LncRNAs bind to targets through the structure and sequence, and thus the mechanisms of action can be complex and specific. Here, we summarized lncRNAs modulating the RNA-activated IFN-I signaling pathway according to the event order during the signaling. We hope this review help understand how lncRNAs are participating in the regulation of IFN-I signaling.

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

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

Repression of lncRNA PART1 attenuates ovarian cancer cell viability, migration and invasion through the miR-503-5p/FOXK1 axis

BACKGROUND

Ovarian cancer (OC) is a female malignant tumor with a high fatality rate. Long non-coding RNAs (lncRNAs) are deeply involved in OC progression. The aim of this study is to explore the specific mechanism of lncRNA prostate androgen-regulated transcript 1 (PART1) in OC.

METHODS

Quantitative real time PCR was utilized to determine the expression levels of PART1, microRNA (miR)-503-5p and forkhead-box k1 (FOXK1) in OC tissues and/or cells. The cell viability, migration, and invasion in OC were evaluated by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-h-tetrazolium bromide assay, wound healing assay and transwell invasion assay, respectively. Flow cytometry was used to analyze the cell apoptosis. The xenograft tumor was conducted in nude mice to verify the effect of PART1 knockdown on OC in vivo. The target relationships among PART1, miR-503-5p and FOXK1 were predicted by StarBase, and verified by luciferase reporter assay. The level of FOXK1 was assessed by western blot.

RESULTS

Increased expression of PART1 and FOXK1 was observed in OC tissues or cells, whereas miR-503-5p was downregulated. PART1 silencing or miR-503-5p overexpression repressed the cell viability, migration and invasion, and protomed apoptosis. Meanwhile, miR-503-5p was a target of PART1, and FOXK1 was a direct target gene of miR-503-5p. Both downregulation of miR-503-5p and upregulation of FOXK1 partly relieved the suppressive effects of PART1 knockdown on the oncogenicity of OC in vitro.

CONCLUSION

Decreased PART1 represses the cell viability, migration and invasion of OC via regulating the miR-503-5p/FOXK1 axis, which provided an underlying target for treating OC.

Homeodomain-containing gene 10 contributed to breast cancer malignant behaviors by activating Interleukin-6/Janus kinase 2/Signal transducer and activator of transcription 3 pathway

Homeodomain‑containing gene 10 (HOXC10) has been identified as an oncogene in various malignancies. Nevertheless, the role and function of HOXC10 in breast cancer (BC) remain unclear. RT-qPCR and Western blot were used to detect the mRNA and protein levels of genes, respectively. CCK-8, transwell, and TUNEL assays were performed to evaluate cell viability, invasion, migration, and apoptosis of BC cells in vitro. The xenograft model was established to examine the effect of HOXC10 on tumor growth in vivo. Our results indicated that HOXC10 expression was increased in BC and correlated with an unsatisfactory prognosis. Functional assays indicated that HOXC10 overexpression promoted cell proliferation and metastasis, and suppressed cell apoptosis of BC, while HOXC10 knockdown showed opposite trends. Furthermore, in vitro and in vivo assays uncovered that HOXC10 promoted the tumorigenesis of BC via the activation of IL-6/JAK2/STAT3 signaling. Overall, our study revealed that HOXC10 could function as a tumor promotor in BC by upregulating IL-6 levels to activate the JAK2/STAT3 signaling pathway.

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

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

Comprehensive analysis of competitive endogenous RNAs networks reveals potential prognostic biomarkers associated with epithelial ovarian cancer

Ovarian cancer (OC) is a major health threat to females, as it has high morbidity and mortality. Evidence has increasingly demonstrated that long non-coding RNAs (lncRNAs) regulate OC progression and they may have value as early diagnostic biomarkers, prognostic biomarkers and/or therapeutic targets. In the present study, the regulatory mechanisms and prognosis associated with cancer-specific lncRNAs and their related competing endogenous (ce)RNA network in OC were investigated. The differential expression profiles and prognostic significance of lncRNAs and mRNAs were systematically explored based on data from 359 OC cases from The Cancer Genome Atlas and 180 healthy individuals from the Genotype-Tissue Expression database. Functional enrichment analyses, RNA-RNA interactome prediction, ceRNA network analysis, correlation analysis and survival analysis were utilized to identify hub lncRNAs and biomarkers associated with OC diagnosis or prognosis. A total of 1,049 differentially expressed lncRNAs and 6,516 differentially expressed mRNAs between OC and healthy tissues were detected. An lncRNA-micro (mi)RNA-mRNA regulatory network in OC was further established, containing 91 lncRNAs, 23 miRNAs and 179 mRNAs. After survival analysis based on the expression of the RNAs in the ceRNA network, 8 lncRNAs, 4 miRNAs and 11 mRNAs that were significantly associated with OC patient survival (P<0.05) were obtained. Using least absolute shrinkage and selection operator-penalized Cox regression, an eight-lncRNA risk score model was generated, which was able to readily discriminate between OC and healthy individuals and predict the survival of patients with OC. In addition, the differential expression of several key lncRNAs and mRNAs was verified by reverse transcription-quantitative PCR and western blot analysis. The current study presents a novel lncRNA-miRNA-mRNA network, which provides insight into the potential pathogenesis of OC and allows the identification of prognostic biomarkers and treatment strategies for OC.

Downregulation of PART1 Inhibits Proliferation and Differentiation of Hep3B Cells by Targeting hsa-miR-3529-3p/FOXC2 Axis

Background

Long noncoding RNAs (lncRNAs) are an important subtype of noncoding RNAs (ncRNAs) and microRNA sponges regulate protein-coding gene expression. The lncRNA prostate androgen-regulated transcript 1 (PART1) was implicated in the process of several cancer pathogeneses. However, studies on the regulation of PART1 expression and its mechanism in liver cancer are lacking.

Methods

qRT-PCR and western blot were used to detect PART1 levels in liver cancer serums and cell lines. Cell proliferation, migration, and invasion were detected using CCK8 assays, cell clones, and transwell assays. Interaction between PART1 and miR-3529-3p and forkhead box protein C2 (FOXC2) was confirmed using dual-luciferase reporter assays.

Results

We revealed that expression levels of PART1 and FOXC2 are significantly upregulated and the miR-3529-3p expression level significantly decreases in the serum while high expression level of PART1 is positively associated with tumour size, BCLC stage, and TNM stage. shRNA of PART1 can significantly reduce the ability of cell migration and invasion by regulating AKT signalling associated with the reduction of MMP-2 and MMP-9 protein expression. Dual-luciferase reporter assays showed that PART1 can sponge miR-3529-3p, which targets FOXC2 in liver cancer cells. The promoting or suppressing effect of PART1 for Hep3B cell proliferation, invasion, and migration is revised by miR-3529-3p mimics and inhibitors.

Conclusion

Results showed that downregulation of PART1 can partially inhibit proliferation and differentiation by targeting hsa-miR-3529-3p/FOXC2 axis.

Identification of a Costimulatory Molecule-Related Signature for Predicting Prognostic Risk in Prostate Cancer

Costimulatory molecules have been proven to enhance antitumor immune responses, but their roles in prostate cancer (PCa) remain unexplored. In this study, we aimed to explore the gene expression profiles of costimulatory molecule genes in PCa and construct a prognostic signature to improve treatment decision making and clinical outcomes. Five prognosis-related costimulatory molecule genes (RELT, TNFRSF25, EDA2R, TNFSF18, and TNFSF10) were identified, and a prognostic signature was constructed based on these five genes. This signature was an independent prognostic factor according to multivariate Cox regression analysis; it could stratify PCa patients into two subgroups with different prognoses and was highly associated with clinical features. The prognostic significance of the signature was well validated in four different independent external datasets. Moreover, patients identified as high risk based on our prognostic signature exhibited a high mutation frequency, a high level of immune cell infiltration and an immunosuppressive microenvironment. Therefore, our signature could provide clinicians with prognosis predictions and help guide treatment for PCa patients.

The Role of Tumor-related LncRNA PART1 in cancer

BACKGROUND

As we all know, long non-coding RNA (lncRNA) affects tumor progression, which has caused a great upsurge in recent years. It can also affect the growth, migration, and invasion of tumors. When we refer to the abnormal expression of lncRNA, we will find it associated with malignant tumors. In addition, lncRNA has been proved to be a key targeted gene for the treatment of some diseases. PART1, a member of lncRNA, has been reported as a regulator in the process of tumor occurrence and development. This study aims to reveal the biological functions, specific mechanisms, and clinical significance of PART1 in various tumor cells.

METHODS

Through the careful search of PUBMED, the mechanisms of the effect of PART1 on tumorigenesis and development are summarized.

RESULTS

On the one hand, the up-regulated expression of PART1 plays a tumor-promoting role in tumors, including lung cancer, prostate cancer, bladder cancer and so on. On the other hand, PART1 is down-regulated in gastric cancer, glioma and other tumors to play a tumor inhibitory role. In addition, PART1 regulates tumor growth mainly by targeting microRNA such as miR-635, directly regulating the expression of proteins such as FUS/EZH2, affecting signal pathways such as the Toll-like receptor pathway, or regulating immune cells.

CONCLUSION

PART1 is closely related to tumors by regulating a variety of molecular mechanisms. In addition, PART1 can be used as a clinical marker for the early diagnosis of tumors and plays an important role in tumor-targeted therapy.

Development and validation of ferroptosis-related lncRNAs signature for hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) with high heterogeneity is one of the most frequent malignant tumors throughout the world. However, there is no research to establish a ferroptosis-related lncRNAs (FRlncRNAs) signature for the patients with HCC. Therefore, this study was designed to establish a novel FRlncRNAs signature to predict the survival of patients with HCC.

Method

The expression profiles of lncRNAs were acquired from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database. FRlncRNAs co-expressed with ferroptosis-related genes were utilized to establish a signature. Cox regression was used to construct a novel three FRlncRNAs signature in the TCGA cohort, which was verified in the GEO validation cohort.

Results

Three differently expressed FRlncRNAs significantly associated with prognosis of HCC were identified, which composed a novel FRlncRNAs signature. According to the FRlncRNAs signature, the patients with HCC could be divided into low- and high-risk groups. Patients with HCC in the high-risk group displayed shorter overall survival (OS) contrasted with those in the low-risk group (P < 0.001 in TCGA cohort and P = 0.045 in GEO cohort). This signature could serve as a significantly independent predictor in Cox regression (multivariate HR > 1, P < 0.001), which was verified to a certain extent in the GEO cohort (univariate HR > 1, P < 0.05). Meanwhile, it was also a useful tool in predicting survival among each stratum of gender, age, grade, stage, and etiology,etc. This signature was connected with immune cell infiltration (i.e., Macrophage, Myeloid dendritic cell, and Neutrophil cell, etc.) and immune checkpoint blockade targets (PD-1, CTLA-4, and TIM-3).

Conclusion

The three FRlncRNAs might be potential therapeutic targets for patients, and their signature could be utilized for prognostic prediction in HCC.

LncRNA PART1 Promotes Proliferation and Migration, Is Associated with Cancer Stem Cells, and Alters the miRNA Landscape in Triple-Negative Breast Cancer

Triple-negative breast cancers (TNBCs) are aggressive, lack targeted therapies and are enriched in cancer stem cells (CSCs). Novel therapies which target CSCs within these tumors would likely lead to improved outcomes for TNBC patients. Long non-coding RNAs (lncRNAs) are potential therapeutic targets for TNBC and CSCs. We demonstrate that lncRNA prostate androgen regulated transcript 1 (PART1) is enriched in TNBCs and in Aldefluor^high CSCs, and is associated with worse outcomes among basal-like breast cancer patients. Although PART1 is androgen inducible in breast cancer cells, analysis of patient tumors indicates its androgen regulation has minimal clinical impact. Knockdown of PART1 in TNBC cell lines and a patient-derived xenograft decreased cell proliferation, migration, tumor growth, and mammosphere formation potential. Transcriptome analyses revealed that the lncRNA affects expression of hundreds of genes (e.g., myosin-Va, MYO5A; zinc fingers and homeoboxes protein 2, ZHX2). MiRNA 4.0 GeneChip and TaqMan assays identified multiple miRNAs that are regulated by cytoplasmic PART1, including miR-190a-3p, miR-937-5p, miR-22-5p, miR-30b-3p, and miR-6870-5p. We confirmed the novel interaction between PART1 and miR-937-5p. In general, miRNAs altered by PART1 were less abundant than PART1, potentially leading to cell line-specific effects in terms miRNA-PART1 interactions and gene regulation. Together, the altered miRNA landscape induced by PART1 explains most of the protein-coding gene regulation changes (e.g., MYO5A) induced by PART1 in TNBC.

LINC00665 promotes cell proliferation, invasion, and metastasis by activating the TGF-β pathway in gastric cancer

BACKGROUND AND AIMS

Accumulating studies have demonstrated that long noncoding RNA plays a vital role in cancer progression. A previous study reported that LINC00665 was overexpressed and acted as a key tumor promoter in lung cancer, but the role of LINC00665 in gastric cancer (GC) remained uncharacterized. Thus, this study aimed to explore the mechanism of LINC00665 in GC.

METHODS

LINC00665 expression was explored using the Cancer Genome Atlas (TCGA), and a meta-analysis was conducted to assess the expression and prognostic value of LINC00665 in GC from Gene Expression Omnibus databases and the TCGA dataset. Real-time polymerase chain reaction (RT-PCR) was then conducted to verify the LINC00665 expression in GC tissues and cell lines. The effects of LINC00665 on cell proliferation, invasion, metastasis, and cell cycle in GC were evaluated using the CCK-8, wound healing, Transwell, and flow cytometry assays. In vitro validation was also performed.

RESULTS

LINC00665 overexpression was found in GC, and LINC00665 upregulation was significantly related to poor overall survival and disease-free survival. LINC00665 expression was associated with tumor depth, lymph node metastasis, and TNM stage. Univariate and multivariate analyses proved that LINC00665 could be an independent prognostic biomarker in GC. LINC00665 knockdown subsequently inhibited cell proliferation, invasion, and metastasis in GC cell lines; promoted cell apoptosis; and arrested GC cell lines in the G0/G1 phase. Western blot analysis indicated that LINC00665 silencing inhibited epithelial-mesenchymal transition and decreased the expression levels of TGF-β1, Smad2, and α-SMA.

CONCLUSION

LINC00665 can be a potential diagnostic and prognostic biomarker for GC patients, and LINC00665 promotes GC cell proliferation, invasion, and metastasis by activating the TGF-β signal pathway.

Development and validation of a set of novel and robust 4-lncRNA-based nomogram predicting prostate cancer survival by bioinformatics analysis

Background and objective

Accumulating evidence shows that long noncoding RNAs (lncRNAs) possess great potential in the diagnosis and prognosis of prostate cancer (PCa). Therefore, this study aimed to construct an lncRNA-based signature to more accurately predict the prognosis of different PCa patients, so as to improve patient management and prognosis.

Methods

Through univariate and multivariate Cox regression analysis, this study constructed a 4 lncRNAs-based prognosis nomogram for the classification and prediction of survival risk in patients with PCa based on TCGA data. Then we used the data of TCGA and ICGC to verify the performance of our prediction model. The receiver operating characteristic curve was plotted for detecting and validating our prediction model sensitivity and specificity. In addition, Cox regression analysis was conducted to examine whether the signature’s prediction ability was independent of additional clinicopathological variables. Possible biological functions for those prognostic lncRNAs were predicted on those 4 protein-coding genes (PCGs) related to lncRNAs.

Results

Four lncRNAs (HOXB-AS3, YEATS2-AS1, LINC01679, PRRT3-AS1) were extracted after COX regression analysis for classifying patients into high and low-risk groups by different OS rates. As suggested by ROC analysis, our proposed model showed high sensitivity and specificity. Independent prognostic capability of the model from other clinicopathological factors was indicated through further analysis. Based on functional enrichment, those action sites for prognostic lncRNAs were mostly located in the extracellular matrix and cell membrane, and their functions are mainly associated with the adhesion, activation and transport of the components across the extracellular matrix or cell membrane.

Conclusion

Our current study successfully identifies a novel candidate, which can provide more convincing evidence for prognosis in addition to the traditional clinicopathological indicators to predict the PCa survival, and laying the foundation for offering potentially novel therapeutic treatment. Additionally, this study sheds more lights on the PCa-related molecular mechanisms.

Long non-coding RNA PART1 predicts a poor prognosis and promotes the malignant progression of pancreatic cancer by sponging miR-122

BACKGROUND AND OBJECTIVES

Long non-coding RNA (lncRNA) prostate androgen-regulated transcript 1 (PART1) was previously shown to exert an oncogenic role in several human cancers. However, whether PART1 is associated with the malignant progression of pancreatic cancer remains unclear. In the current study, we aimed to identify the role and potential mechanism of PART1 in pancreatic cancer.

METHODS

qRT-PCR was applied to detect PART1 expression in 45 cases of pancreatic cancer patients. The chi-square test was performed to assess the association between PART1 expression and clinicopathologic features, and Kaplan-Meier method was applied to evaluate overall survival. In vitro CCK-8, transwell invasion, and flow cytometry assays were applied to detect the effects of PART1 on cell proliferation, invasion, and apoptosis, respectively. Luciferase reporter and RNA immunoprecipitation assays were used to identify the regulatory mechanism between PART1 and miR-122.

RESULTS

PART1 expression was upregulated in pancreatic cancer tissues and cell lines. High PART1 expression was closely correlated with tumor size, T classification, clinical stage, and vascular invasion, and predicted a poor overall survival. PART1 knockdown significantly suppressed cell proliferation and invasion abilities of pancreatic cancer but promoted cell apoptosis. PART1 was found to serve as a molecular sponge of miR-122, and miR-122 inhibition partially reversed the inhibitory phenotypes of PART1 knockdown on pancreatic cancer cells.

CONCLUSIONS

PART1 promotes the malignant progression of pancreatic cancer by sponging miR-122. The PART1/miR-122 axis might be a promising target for anticancer therapy in patients with pancreatic cancer.

LncRNA PART1 promotes cell proliferation and progression in non-small-cell lung cancer cells via sponging miR-17-5p

It has been demonstrated in previous studies that lncPART1 is dysregulated in non-small cell lung cancer (NSCLC). However, the function of lncPART1 in NSCLC is unclear. Therefore, this experimental design was based on LncPART1 to explore the pathogenesis of NSCLC. Real-time polymerase chain reaction was used to detect the expression of lncPART1 and miR-17-5p in NSCLC. Cell Counting Kit -8, colony formation, and transwell assays were used to examine the effects of lncPART1 and miR-17-5p on NSCLC cell proliferation and migration invasiveness. Target gene prediction, luciferase reporter assays were used to validate downstream target genes for lncPART1 and miR-17-5p. Western blot analysis was used to detect the expression of TGFBETAR2. LncPART1 was highly expressed in NSCLC. LncPART1 significantly promoted cell proliferation of NSCLC cells. miR-17-5p was down-expressed in NSCLC. miR-17-5p overexpression inhibited cell proliferation and migration invasion in NSCLC cells. LncPART1 was able to inhibit miR-17-5p expression and upregulate the expression level of TGFBETAR2. The results of in vivo animal models confirmed that lncPART1 promoted NSCLC progression by miR-17-5p/TGFBETAR2 axis. LncPART1 promoted the progression of NSCLC by miR-17-5p/TGFBETAR2 axis.

LncRNA PART1 promotes cell proliferation and inhibits apoptosis of oral squamous cell carcinoma by blocking EZH2 degradation

Long noncoding RNAs (lncRNAs) have been considered as novel regulators in oral squamous cell carcinoma (OSCC). Enhancer of zeste homolog 2 (EZH2) can act as an oncogene in OSCC. This study intended to investigate whether lncRNA PART1 can exert its role in OSCC by regulating EZH2. The expression of PART1 in OSCC samples, tumors tissues, or OSCC cell lines was detected by qRT-PCR. The proliferation and apoptosis of OSCC cells were detected by CCK-8 and flow cytometry assays, respectively. The expression of PART1 and EZH2 were highly expressed in clinical OSCC tumors and cell lines. The expression level of PART1 was positively correlated to the size, clinical stage, and node metastasis of OSCC patients. Functionally, PART1 knockdown inhibited proliferation and facilitated apoptosis of OSCC cells. Mechanically, FUS interacted with PART1 and EZH2. Additionally, PART1 knockdown reduced the mRNA expression of EZH2, which was offset by FUS overexpression. The overexpression of FUS abrogated the effects of PART1 silence on proliferation and apoptosis of OSCC cells. The in vivo experiment revealed that PART1 knockdown inhibited tumor growth of OSCC cells in nude mice. This study indicated that PART1 exerts a carcinogenic role in OSCC by enhancing the stability of EZH2 protein.

lncRNA PART1, manipulated by transcriptional factor FOXP2, suppresses proliferation and invasion in ESCC by regulating the miR‑18a‑5p/SOX6 signaling axis

An increasing number of studies have demonstrated that long non-coding (lnc)RNAs are associated with tumor invasion, metastasis and the prognosis of patients with a variety of different tumors. However, the roles of lncRNA prostate androgen regulated transcript 1 (PART1) in esophageal squamous cell carcinoma (ESCC) remain unknown. In the present study, reverse transcription-quantitative PCR was performed to investigate the levels of PART1, SRY-box transcription factor 6 (SOX6) and miR-18a-5p in ESCC tissues and cells. The functions of PART1 in ESCC were demonstrated using Cell Counting Kit-8 and Matrigel assays. Promoter activity and dual-luciferase reporter assays, RNA immunoprecipitation and western blot analyses were also used to determine the potential mechanisms of PART1 in ESCC cell lines. It was found that PART1 and SOX6 were both downregulated in ESCC tissues and cells, and their low expression levels were associated with TNM stage, lymph node metastasis and poor prognosis in patients with ESCC. Forkhead box protein P2 (FOXP2) exhibited low expression level in ESCC tissues, and its expression was positively correlated with PART1 expression level in ESCC tissues. FOXP2 was found to bind to the promoter region of PART1 to regulate its expression in ESCC cells. Functionally, PART1 overexpression suppressed cell proliferation and invasion, whereas PART1 downregulation promoted cell proliferation and invasion in the ESCC cell lines. Mechanistically, PART1 functions as a competing endogenous (ce)RNA by sponging miR-18a-5p, resulting in the upregulation of the downstream target gene, SOX6, coupled with the inactivation of the β-catenin/c-myc signaling axis, to suppress ESCC cell proliferation and invasion. In conclusion, data from the present study unveil a potential ceRNA regulatory pathway, in which PART1 affects SOX6 expression level by sponging miR-18a-5p, to ultimately suppress ESCC development and progression.

LncRNA PART1 promotes lung squamous cell carcinoma progression via miR-185-5p/Six1 axis

Dysregulation of the long non-coding RNA prostate androgen regulated transcript 1 (lncRNA PART1) is involved in the tumorigenesis of various cancers. However, little is known about its function and molecular mechanism in the development of lung squamous cell carcinoma (LSCC). In this study, we examined the expression of PART1 in LSCC clinical tissue samples and cell lines, and gain- and loss-of-function experiments were performed to explore the function of PART1 in LSCC proliferation, invasion and migration. We found that PART1 was overexpressed in both LSCC tissues and cell lines. Functional studies revealed that PART1 knockdown significantly suppressed cell proliferation, invasion and migration but enhanced apoptosis in LSCC cells, whereas overexpression of PART1 showed the opposite results. Mechanistically, we identified that PART1 acted as a sponge of miR-185-5p, and sineoculis homeobox homolog 1 (Six1) was a direct downstream target of miR-185-5p. Moreover, restoration of miR-185-5p or silencing of Six1 partially abolished the oncogenic effect of PART1 in LSCC cells. Clinically, The areas under the receiver operating characteristic (ROC) curve of PART1, miR-185-5p, and Six1 were 0.7857, 0.7332, 0.8112, respectively. Notably, high PART1, low miR-185-5p, and high Six1 expressions were significantly associated with severe clinical parameters and were the independent risk factors for poor prognosis of LSCC patients. Thus, we concluded that the PART1/miR-185-5p/Six1 axis might serve as a novel biomarker for the diagnosis and treatment of LSCC.

Role of lncRNA PART1 in intervertebral disc degeneration and associated underlying mechanism

Intervertebral disc degeneration (IDD) is a chronic skeletal muscle degeneration disease. Previous studies have demonstrated that long non-coding RNAs (lncRNAs) exert significant roles in serious illnesses. Prostate androgen-regulated transcript 1 (PART1) is an identified lncRNA that has been reported to be a regulator in a number of diseases. However, the potential effects of PART1 in IDD have yet to be fully elucidated. The present study aimed to investigate the roles of lncRNA PART1 in IDD and identify a possible underlying mechanism. Human nucleus pulposus (NP) cells were first exposed to lipopolysaccharide (LPS) to construct in vitro IDD models. Reverse transcription-quantitative PCR (RT-qPCR) was performed to measure lncRNA PART1 expression levels in 10 ng/ml LPS-stimulated NP cells and normal cells (untreated cells). Dual-luciferase reporter assays were conducted to verify the possible binding sites of microRNA (miR)-190a-3p on lncRNA PART1. In addition, NP cell viability and apoptosis were measured by performing MTT and flow cytometry, respectively. Expression and secretion of inflammatory factors (TNF-α, IL-1β and IL-6) and extracellular matrix (ECM) degradation-related proteins (aggrecan and collagen type II) were measured using ELISA, RT-qPCR and western blotting. Expression levels of lncRNA PART1 in LPS-treated NP cells were found to be higher compared with those in the control groups. miR-190a-3p directly targeted lncRNA PART1. PART1 knockdown enhanced cell viability, reduced cell apoptosis, inhibited inflammatory factor secretion and promoted ECM degradation in LPS-stimulated NP cells. However, transfection with the miR-190a-3p inhibitor reversed the aforementioned PART1 knockdown-induced alterations in cell viability, apoptosis, inflammatory cytokine and ECM degradation. Collectively, these results suggest that PART1 accelerates the progression of IDD by directly targeting miR-190a-3p, which provides a novel target for IDD diagnosis and treatment.

Targeting Toll like Receptors in Cancer: Role of TLR Natural and Synthetic Modulators

Background:

Toll like receptors (TLRs) are a group of transmembrane receptors belonging to the broad class pattern recognition receptors (PRR), involved in recognition of Pathogen Associated Molecular Patterns (PAMPs) thereby inducing an immune response. Apart from these exogenous PAMPs, numerous endogenous PAMPs are also ligands for various TLRs thereby activating the TLR dependent immune response, subsequently leading to the onset of an inflammatory response. Prolonged activation of TLR by these endogenous PAMPs leads to chronic inflammatory insults to the body and which in turn alters the proliferative patterns of the cells, which ultimately leads to the development of cancer.

Objectives:

The present review aims to provide a detailed outline of the differential roles of various TLRs in cancer and the possible use of them as a therapeutic target.

Methods:

Data were collected from PubMed/Sciencedirect/Web of Science database and sorted; the latest literature on TLRs was incorporated in the review.

Results:

Among the different TLRs, few are reported to be anti-neoplastic, which controls the cell growth and multiplication in response to the endogenous signals. On the contrary, numerous studies have reported the procarcinogenic potentials of TLRs. Hence, TLRs have emerged as a potential target for the prevention and treatment of various types of cancers. Several molecules, such as monoclonal antibodies, small molecule inhibitors and natural products have shown promising anticancer potential by effectively modulating the TLR signalling.

Conclusion:

Toll-like receptors play vital roles in the process of carcinogenesis, hence TLR targeting is a promising approach for cancer prevention.

Exploring the Roles of lncRNAs in GBM Pathophysiology and Their Therapeutic Potential

Glioblastoma (GBM) remains the most devastating primary central nervous system malignancy with a median survival of around 15 months. The past decades of research have not yielded significant advancements in the treatment of GBM. In that same time, a novel class of molecules, long non-coding RNAs (lncRNAs), has been found to play a multitude of roles in cancer and normal biology. The increased accessibility of next generation sequencing technologies and the advent of lncRNA-specific microarrays have facilitated the study of lncRNA etiology. Molecular and computational methods can be applied to predict lncRNA function. LncRNAs can serve as molecular decoys, scaffolds, super-enhancers, or repressors. These molecules can serve as phenotypic switches for GBM cells at the expression and/or epigenetic levels. LncRNAs can affect stemness/differentiation, proliferation, invasion, survival, DNA damage response, and chromatin dynamics. Aberrant expression of these transcripts may facilitate therapy resistance, leading to tumor recurrence. LncRNAs could serve as novel theragnostic or prognostic biomarkers in GBM and other cancers. RNA-based therapeutics may also be employed to target lncRNAs as a novel route of treatment for primary or recurrent GBM. In this review, we explore the roles of lncRNAs in GBM pathophysiology and posit their novel therapeutic potential for GBM.

LncRNA PART1 Exerts Tumor-Suppressive Functions in Tongue Squamous Cell Carcinoma via miR-503-5p

Background

Tongue squamous cell carcinoma (TSCC) accounts for one-third of oral cancers. Previous studies had reported that lncRNA/miRNA regulated the biological behaviors of different cancer cells. However, the mechanisms of PART1 in regulating tumorigenesis and TSCC development via targeting miR-503-5p had not been studied.

Methods

The expressions of PART1 and miR-503-5p in tissues and cultured cell lines were detected by qRT-PCR. StarBase 3.0 was used to predict the binding sites of PART1, then dual-luciferase assay and RNA pull-down assay were executed to confirm whether miR-503-5p was a target of PART1. TSCC cells were co-transfected with PART1-overexpressed plasmid or miR-503-5p mimics in vitro, and the transfection efficiency was evaluated through qRT-PCR. Western blot was performed to assess the expressions of EMT-related proteins. CCK-8 and clone formation assays were conducted to detect cell proliferation, TUNEL assay was used to detect apoptosis, and transwell assay was executed to test migration and invasion.

Results

The low PART1 expression and high miR-503-5p expression were found in TSCC tissues and cell lines (CAL-27 and SCC9). PART1 expression was positively correlated with patients’ prognosis. The targeting and binding relationship between PART1 and miR-503-5p was confirmed, and overexpressed PART1 diminished the expression of miR-503-5p as well. Moreover, PART1 facilitated apoptosis, inhibited proliferation, invasion and migration of TSCC cells, and these influences were impeded by miR-503-5p overexpression.

Conclusion

LncRNA PART1 played a cancer-suppressing role in TSCC by targeting miR-503-5p, which provided a potential target for TSCC treatment.

lncRNA PART1 and MIR17HG as ΔNp63α direct targets regulate tumor progression of cervical squamous cell carcinoma

Cervical cancer (CC) remains one of the leading causes of mortality of female cancers worldwide, with more than 90% being cervical squamous cell carcinoma (CSCC). ΔNp63α is the predominant isoform expressed in cervical epithelial tissues and exerts its antitumor function in CSCC. In this study, we have identified 39 long noncoding RNAs as ΔNp63α targets in CSCC through RNA sequencing and chromatin immunoprecipitation sequencing, in which we further confirmed and focused on the two tumor‐related long noncoding RNAs, PART1 (lncPART1) and MIR17HG (lncMIR17HG). Experiments from stable overexpression/knockdown cell lines revealed that lncPART1 and lncMIR17HG regulated cell proliferation, migration, and invasion. In vivo experiments further showed that lncPART1 suppresses tumor growth in CSCC‐derived tumors. Examinations of clinical tissues indicated that the expression of lncPART1 was positively correlated with ΔNp63α expression, while lncMIR17HG was negatively correlated with ΔNp63α expression, suggesting that ΔNp63α plays a central role via regulating its direct targets in the progression of CSCC. These findings provide novel insights in targeted therapy of cervical cancers.

Dysregulation of LncRNA ANRIL mediated by miR-411-3p inhibits the malignant proliferation and tumor stem cell like property of multiple myeloma via hypoxia-inducible factor 1α

Long non-coding RNA (lncRNA) ANRIL has been reported to be closely related to the relapse of multiple myeloma patients. However, the functional role and underlying mechanism of lncRNA ANRIL in multiple myeloma are not known. This study aims to investigate the biological function of lncRNA ANRIL in multiple myeloma. In this study, compared with normal tissues from healthy donors, lncRNA ANRIL and HIF-1α expressions were up-regulated in tumor tissues from multiple myeloma patients. miR-411-3p expression was down-regulated in tumor tissues from multiple myeloma patients. Besides, lncRNA ANRIL can interact with miR-411-3p. HIF-1α was confirmed to be a target of miR-411-3p. Correlation analysis showed that lncRNA ANRIL expression was negatively correlated with miR-411-3p expression. HIF-1α expression was negatively correlated with miR-411-3p expression. Further transfection experiments showed that knockdown of ANRIL or overexpression of miR-411-3p significantly inhibited cell proliferation, tumor formation ability and tumor stem cell like property, promoted cell apoptosis in vitro. Finally, miR-411-3p mimic reduced tumor volume, improved survival rate, suppressed malignant proliferation and tumor stem cell like property in U266 xenograft model. Our results demonstrate that lncRNA ANRIL mediated by miR-411-3p promotes the malignant proliferation and tumor stem cell like property of multiple myeloma through regulating HIF-1α.

Long noncoding RNA PART1 restrains aggressive gastric cancer through the epigenetic silencing of PDGFB via the PLZF-mediated recruitment of EZH2

Current reports refer to the role of long noncoding RNA (lncRNA) prostate androgen-regulated transcript 1 (PART1) as a tumor suppressor in some types of cancer but as an oncogene in other kinds of cancer. In gastric cancer, it had been reported to be downregulated. However, the clinical significance and underlying mechanism of PART1 function in gastric cancer remains undefined. Here, seven differential expression levels of noncoding RNAs (DE-lncRNAs) were screened from gastric cancer through a probe reannotation of a human exon array. PART1 was selected for further study because of its high fold change number. In our cohort, PART1 was identified as a significant downregulated lncRNA in gastric cancer tissues by qPCR and in situ hybridization (ISH), and its low expression was significantly correlated with postoperative metastasis and short overall survival time after surgery. Through the results of gain-of-function experiments, PART1 was confirmed as a tumor suppressor that can decrease not only cell viability, migration, and invasion in vitro but also tumorigenesis and tumor metastasis in vivo. Mechanistically, RNA pull-down and RNA-binding protein immunoprecipitation (RIP) showed that PART1 interacts with androgen receptor (AR), and then, promyelocytic leukemia zinc finger (PLZF) is upregulated in an androgen-independent manner. In a chain reaction, chromatin immunoprecipitation (ChIP) assay additionally illustrated that PLZF upregulation increased the enrichment of EZH2 and H3K27 trimethylation in the platelet-derived growth factor (PDGFB) promotor, thereby inhibition of PDGFB and the subsequent PDGFRβ/PI3K/Akt signaling pathway. Based on these findings, we showed PART1 plays a tumor suppressor role by promoting PLZF expression followed by recruitment of EZH2 to mediate epigenetic PDGFB silencing and downstream PI3K/Akt inhibition, suggesting that PART1 has a key role in restraining the aggressive ability of GC cells and providing a novel perspective on lncRNAs in GC progression.

lncRNA PART1 Promotes Breast Cancer Cell Progression by Directly Targeting miR-4516

Introduction

Breast cancer is a serious threat to human health. It is meaningful to study the pathogenesis of breast cancer. lncRNAs have been found to play vital roles in numerous biological processes including development, immunology and cancer.

Methods

qRT-PCR was performed to examine the expressions of PART1 and miR-4516. CCK-8 assay, colony formation assay and transwell assay were used to examine the progression of breast cancer cells.

Results

In this study, we showed that lncRNA PART1 was highly expressed in breast cancer cells. Knockdown of PART1 induced decreased proliferation, invasion and migration of breast cancer cells. Moreover, we found that PART1 can bind to miR-4516 directly. We also found that inhibition of miR-4516 could rescue the decreased proliferation, migration and invasion of breast cancer cells induced by knockdown of PART1.

Discussion

lncRNA PART1 and miR-4516 were proven to be involved in the progression of many cancers. However, the roles of lncRNA PART1 and miR-4516 in the regulation of breast cancer remain unknown. Here, we demonstrated that PART1 can bind to miR-4516 to decrease the expression of miR-4516 and promote the development of breast cancer.

Toll-like Receptors as a Novel Therapeutic Target for Natural Products Against Chronic Diseases

Toll-like receptors (TLR) are one among the initial responders of the immune system which participate in the activation inflammatory processes. Several different types of TLR such as TLR2, TLR4, TLR7 and TLR9 have been identified in various cell types, each having distinct ligands like lipids, lipoproteins, nucleic acids and proteins. Though its prime concern is xenobiotic defences, TLR signalling has also recognized as an activator of inflammation and associated development of chronic degenerative disorders (CDDs) including obesity, type 2 diabetes mellitus (T2DM), fatty liver disease, cardiovascular and neurodegenerative disorders as well as various types of cancers. Numerous drugs are in use to prevent these disorders, which specifically inhibit different pathways associated with the development of CDDs. Compared to these drug targets, inhibition of TLR, which specifically responsible for the inflammatory insults has proven to be a better drug target. Several natural products have emerged as inhibitors of CDDs, which specifically targets TLR signalling, among these, many are in the clinical trials. This review is intended to summarize the recent progress on TLR association with CDDs and to list possible use of natural products, their combinations and their synthetic derivative in the prevention of TLR-driven CDD development.