The relationship between lncRNA PCGEM1 and STAT3 during the occurrence and development of endometrial carcinoma

The Promotive and Inhibitory Role of Long Non-Coding RNAs in Endometrial Cancer Course-A Review

Endometrial cancer is one of the most common malignant tumours in women. The development of this tumour is associated with several genetic disorders, many of which are still unknown. One type of RNA molecules currently being intensively studied in many types of cancer are long non-coding RNAs (lncRNAs). LncRNA-coding genes occupy a large fraction of the human genome. LncRNAs regulate many aspects of cell development, metabolism, and other physiological processes. Diverse types of lncRNA can function as a tumour suppressor or an oncogene that can alter migration, invasion, cell proliferation, apoptosis, and immune system response. Recent studies suggest that selected lncRNAs are important in an endometrial cancer course. Our article describes over 70 lncRNAs involved in the development of endometrial cancer, which were studied via in vivo and in vitro research. It was proved that lncRNAs could both promote and inhibit the development of endometrial cancer. In the future, lncRNAs may become an important therapeutic target. The aim of this study is to review the role of lncRNAs in the development of carcinoma of uterine body.

The cross-talk between LncRNAs and JAK-STAT signaling pathway in cancer

Long non-coding RNAs (lncRNAs) are non-coding RNAs that were transcribed from the human genome and have become important regulators in a number of cellular activities, mostly via controlling gene expression. A growing body of evidence shows that lncRNAs regulate various factors to impact various biological activities that are related to tumorigenesis, including the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway. lncRNAs influence the JAK-STAT signaling pathway either by directly targeting or via indirectly modulating other upstream or downstream pathways' components like members of the suppressor of cytokine signaling (SOCS) family, and other genes that regulate cell proliferation, apoptosis, migration, invasion, and epithelial-mesenchymal transition. Furthermore, lncRNAs can act as downstream effectors of the JAK-STAT pathway and mediates tumorigenesis. The relationship between JAK-STAT signaling and lncRNAs differs among various types of cancers. Besides, lncRNAs, as biological molecules, have been shown to play a dual role in either tumorigenesis or tumor suppression in various cancers. In this review, we focus on the reciprocated regulation and functions of lncRNAs and the JAK-STAT signaling pathway in cancer, as well as narrate the latest research progress on this association. A deeper understanding of this correlation may simplify the recognition of potential targets for clinical therapeutics.

PCGEM1 promotes cell proliferation and migration in endometriosis by targeting miR-124-3p-mediated ANTXR2 expression

BACKGROUND

Endometriosis, a common gynaecological disease in women, affects 10% of women of childbearing age. Among infertile women, this proportion is as high as 30-50%. Despite the high prevalence of endometriosis, the pathogenesis of endometriosis is still unclear.

METHODS

In the present study, bioinformatics analysis and molecular and animal experiments were employed to explore the functions of PCGEM1 in the pathogenesis of endometriosis. We established an endometriosis rat model and isolated endometrial stromal cells (ESCs) and primary normal ESCs (NESCs). Bioinformatics analysis was adopted to study the roles of PCGEM1 in promoting the pathogenesis of endometriosis. Luciferase reporter assays and RNA pull-down assays were carried out to study the mechanism by which PCGEM1 regulates ANTXR2.

RESULTS

Our results indicated that PCGEM1 promoted the motility and proliferation of ectopic endometrial cells, and the underlying mechanism was due to the direct binding of PCGEM1 to miR-124-3p to modulate ANTXR2 expression.

CONCLUSION

PCGEM1 can influence endometrial stromal cell proliferation and motility and may be a novel therapeutic target for endometriosis.

Long Noncoding RNA PCGEM1 Facilitates Tumor Growth and Metastasis of Osteosarcoma by Sponging miR-433-3p and Targeting OMA1

OBJECTIVE

Osteosarcoma (OS) is regarded as one of the most common malignant bone tumors, mainly occurring in children and adolescents with high mortality. The dysregulation of lncRNAs is reported to regulate tumor development and be closely related to patient prognosis. Nevertheless, the role of long noncoding RNAs (lncRNAs) prostate-specific transcript 1 (PCGEM1) in OS remains uncharacterized. The current study aimed to explore the role of PCGEM1 in OS.

METHODS

Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to examine the expression of PCGEM1 in OS cell lines. CCK-8, colony formation, Transwell, and western blotting analyses were applied to measure OS cell viability, proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) after PCGEM1 downregulation. Nuclear-cytoplasmic fractionation, RNA pulldown, RNA immunoprecipitation (RIP), luciferase reporter assays were performed to verify the relationship among PCGEM1, miR-433-3p. and OMA1 in OS. The xenograft tumor models were established to evaluate the effect of PCGEM1 on tumor growth of OS.

RESULTS

In this study, we discovered that PCGEM1 knockdown inhibited cell proliferation, migration, invasion and EMT in OS (P < 0.05). Additionally, PCGEM1 directly bound to miR-433-3p (P < 0.01). OMA1 was confirmed to be a target gene of miR-433-3p (P < 0.05), positively regulated by PCGEM1 but negatively regulated by miR-433-3p. Rescue assays further verified that overexpression of OMA1 reversed the PCGEM1 knockdown-mediated inhibitory effect on the malignant phenotype in OS cells (P < 0.05). Moreover, knockdown of PCGEM1 inhibited tumor growth and metastasis in vivo (P < 0.05).

CONCLUSIONS

Overall, PCGEM1 mediated tumor growth and metastasis of OS by sponging miR-433-3p and regulating OMA1, which might provide an innovative strategy for OS diagnosis or treatment.

lncRNA PCGEM1 Regulates the Progress of Colorectal Cancer through Targeting miR-129-5p/SOX4

Prostate cancer gene expression marker 1 (PCGEM1) has abnormal expression level in a variety of malignant tumor. However, the relationship between PCGEM1 and colorectal cancer is still unclear yet. This study is aimed at identifying the role of PCGEM1 in colorectal cancer. qRT-PCR was used to examine the expressions of the expression of lncRNA PCGEM1 and SOX4 in CRC tissues and cell lines. The biological functions of lncRNA PCGEM1 and SOX4 were examined by CCK-8 assay, Transwell assay, immunohistochemistry, western blotting, RNA interference, and gene overexpression techniques. Bioinformatics analysis was used to find the potential downstream molecule of PCGEM1 and miR-129-5p. The relationship between PCGEM1, miR-129-5p, and SOX4 was assessed by dual luciferase activity assay. We found that PCGEM1 is overexpressed in colorectal cancer cells and tissues, while miR-129-5p is underexpressed. SOX4 is overexpressed in colorectal cancer cells and tissues. Functionally, PCGEM1 silencing can significantly inhibit the proliferation, invasion, and migration of colorectal cancer cells. Mechanically, PCGEM1 acted as a sponge for miR-129-5p and absorbed its expression, and miR-129-5p was found to target SOX4, constructing the axis of PCGEM1/miR-129-5p/SOX4 in colorectal cancer. In conclusion, PCGEM1 mediates the proliferation, invasion, and migration of colorectal cancer cells by targeting miR-129-5p/SOX4 axis.

Long non-coding RNA-PCGEM1 contributes to prostate cancer progression by sponging microRNA miR-129-5p to enhance chromatin licensing and DNA replication factor 1 expression

PCGEM1 facilitates prostate cancer (PCa) progression. This study aimed to elucidate the mechanism of action of PCGEM1 in PCa. The expression of PCGEM1, microRNA miR-129-5p, chromatin licensing, and DNA replication factor 1 (CDT1) was detected by quantitative reverse transcription-PCR (qRT-PCR). A series of function experiments including cell counting kit-8 (CCK-8), caspase-3 activity, and cell cycle assays were performed to evaluate the influence of PCGEM1, miR-129-5p, and CDT1 on the biological processes of PCa cells. CyclinD1, cyclin dependent kinase 4 (CDK4), Bax, and Bcl-2 protein levels were measured by western blotting. Subcellular isolation revealed the distribution of PCa cells. The connections between PCGEM1, miR-129-5p, and CDT1 were evaluated by luciferase, RIP assay, and Pearson correlation analysis. Both PCGEM1 and CDT1 were upregulated in PCa, while miR-129-5p was downregulated and negatively correlated with PCGEM1 and CDT1. Downregulation of PCGEM1 or CDT1 inhibited the viability, promoted apoptosis and cycle arrest of PCa cells in vitro, and controlled tumor growth in vivo. PCGEM1 plays a crucial role in the progression of PCa by sponging miR-129-5p as a ceRNA of CDT1. PCGEM1 is a CDT1-dependent PCa promoter site that absorbs miR-129-5p.

Signal transducer and activator of transcription family is a prognostic marker associated with immune infiltration in endometrial cancer

BACKGROUND

Signal transducer and activator of transcription (STAT) is a unique protein family that binds to DNA and plays a vital role in regulating major physiological cellular processes. Seven STAT genes have been identified in the human genome. Several studies suggest STAT family members to be involved in cancer development, progression, and metastasis. However, the predictive relationship between STAT family expression and immune cell infiltration in endometrial cancer remains unknown.

METHODS

We explored STAT family expression and prognosis in endometrial cancer using various databases. The STRING, GeneMANIA, and DAVID databases, along with GO and KEGG analyses, were used to construct a protein interaction network of related genes. Finally, the TIMER database and ssGSEA immune infiltration algorithm were used to investigate the correlation of STAT family expression with the immune infiltration level in uterine corpus endometrial carcinoma (UCEC).

RESULTS

Our study showed that different STAT family members are differentially expressed in UCEC. STAT1 and STAT2 expression increased at various stages of UCEC, and STAT5A, STAT5B, and STAT6 levels were decreased. STAT3 and STAT4 expression was not significantly different between UCEC and normal tissues. High STAT1 expression may be a prognostic disadvantage of UCEC, and high STAT6 expression may improve UCEC patient prognosis. The STAT family-associated genes were significantly enriched in signal transduction, protein binding, DNA binding, and ATP binding upon GO analysis. Related genes in the KEGG analysis were mainly enriched in pathways in cancer, viral carcinogenesis, chemokine signaling pathway, JAK/STAT signaling pathway, and regulation of the actin cytoskeleton. In terms of immune infiltration, STAT1 and STAT2 were positively correlated with B, CD8+ T, CD4+ T, and dendritic cells, and neutrophils (p < 0.05). All STAT family members were positively correlated with neutrophils and dendritic cells (p < 0.05). STAT1 and STAT2 showed similar correlations with all immune cell types, whereas STAT1 and STAT6 showed opposite correlations.

CONCLUSION

These findings suggest that the STAT family is a prognostic marker, and the immune infiltration level, a therapeutic target, for endometrial cancer.

LncRNA PCGEM1 in Human Cancers: Functions, Mechanisms and Promising Clinical Utility

As novel members of the noncoding RNA family, long noncoding RNAs (lncRNAs) have been widely reported to function as powerful regulators in gene expression processes, including chromosome remodeling, transcription interference and posttranscriptional modification. With the rapid development of metagenomic sequencing, numerous studies have indicated that the dysregulation of lncRNAs is closely associated with diverse human diseases, especially cancers. Prostate Gene Expression Marker 1 (PCGEM1), a recently identified lncRNA, has been reported to play a crucial role in the initiation and progression of multiple tumors by interacting with pivotal regulators of tumor-related signaling pathways. In this review, we will retrospectively review the recent studies of the expression of lncRNA PCGEM1 in human cancers and comprehensively describe the underlying regulatory mechanism by which PCGEM1 functions in tumors. More importantly, based on the relationship between PCGEM1 and cancers, the potential application of PCGEM1 in clinical diagnosis, prognosis and therapeutic treatment will also be highlighted.

The Role of Long Non-Coding RNAs (lncRNAs) in Female Oriented Cancers

Recent advances in molecular biology have discovered the mysterious role of long non-coding RNAs (lncRNAs) as potential biomarkers for cancer diagnosis and targets for advanced cancer therapy. Studies have shown that lncRNAs take part in the incidence and development of cancers in humans. However, previously they were considered as mere RNA noise or transcription byproducts lacking any biological function. In this article, we present a summary of the progress on ascertaining the biological functions of five lncRNAs (HOTAIR, NEAT1, H19, MALAT1, and MEG3) in female-oriented cancers, including breast and gynecological cancers, with the perspective of carcinogenesis, cancer proliferation, and metastasis. We provide the current state of knowledge from the past five years of the literature to discuss the clinical importance of such lncRNAs as therapeutic targets or early diagnostic biomarkers. We reviewed the consequences, either oncogenic or tumor-suppressing features, of their aberrant expression in female-oriented cancers. We tried to explain the established mechanism by which they regulate cancer proliferation and metastasis by competing with miRNAs and other mechanisms involved via regulating genes and signaling pathways. In addition, we revealed the association between stated lncRNAs and chemo-resistance or radio-resistance and their potential clinical applications and future perspectives.

RHO GTPase-Related Long Noncoding RNAs in Human Cancers

RHO GTPases are critical signal transducers that regulate cell adhesion, polarity, and migration through multiple signaling pathways. While all these cellular processes are crucial for the maintenance of normal cell homeostasis, disturbances in RHO GTPase-associated signaling pathways contribute to different human diseases, including many malignancies. Several members of the RHO GTPase family are frequently upregulated in human tumors. Abnormal gene regulation confirms the pivotal role of lncRNAs as critical gene regulators, and thus, they could potentially act as oncogenes or tumor suppressors. lncRNAs most likely act as sponges for miRNAs, which are known to be dysregulated in various cancers. In this regard, the significant role of miRNAs targeting RHO GTPases supports the view that the aberrant expression of lncRNAs may reciprocally change the intensity of RHO GTPase-associated signaling pathways. In this review article, we summarize recent advances in lncRNA research, with a specific focus on their sponge effects on RHO GTPase-targeting miRNAs to crucially mediate gene expression in different cancer cell types and tissues. We will focus in particular on five members of the RHO GTPase family, including RHOA, RHOB, RHOC, RAC1, and CDC42, to illustrate the role of lncRNAs in cancer progression. A deeper understanding of the widespread dysregulation of lncRNAs is of fundamental importance for confirmation of their contribution to RHO GTPase-dependent carcinogenesis.

Towards Personalized Medicine: Non-Coding RNAs and Endometrial Cancer

Endometrial cancer (EC) is the most frequent female cancer associated with excellent prognosis if diagnosed at an early stage. The risk factors on which clinical staging is based are constantly updated and genetic and epigenetic characteristics have recently been emerging as prognostic markers. The evidence shows that non-coding RNAs (ncRNAs) play a fundamental role in various biological processes associated with the pathogenesis of EC and many of them also have a prognosis prediction function, of remarkable importance in defining the therapeutic and surveillance path of EC patients. Personalized medicine focuses on the continuous updating of risk factors that are identifiable early during the EC staging to tailor treatments to patients. This review aims to show a summary of the current classification systems and to encourage the integration of various risk factors, introducing the prognostic role of non-coding RNAs, to avoid aggressive therapies where not necessary and to treat and strictly monitor subjects at greater risk of relapse.

Histopathologic, Genetic and Molecular Characterization of Endometrial Cancer Racial Disparity

Simple Summary

Black patients are diagnosed and die earlier of endometrial cancer in comparison with their White counterparts. Factors that have been implicated in this racial disparity, such as socioeconomic status, increased frequencies of more aggressive tumor histology, and comorbid conditions, do not account for all of the disparity. Molecular defects in the endometrial tumors likely also contribute to the more aggressive tumor biology and the patient disparities. In this study, we reviewed the published data of molecular characteristics of endometrial cancer in different races. The majority of the publications compare Black and White patients, and identify molecules and pathways that can be targeted with existing drugs. These findings encourage molecular profile studies comparing additional races and ethnicities, and development of race-specific treatments.

Abstract

In contrast to the decline in incidence and mortality of most other cancers, these rates are rising for endometrial cancer. Black women with endometrial cancer have earlier diagnosis, more aggressive histology, advanced stage and worse outcomes compared with their White counterparts. Socioeconomic status, a higher incidence of aggressive histology, and comorbid conditions are known factors leading to racial disparity in patients with endometrial cancer; nevertheless, they do not account for the entire racial disparity; which emphasizes the roles of molecular, histopathological and genetic factors. We performed a comprehensive review of all published scientific literature up to January 2021 reporting histopathologic, genetic and molecular factors associated with racial disparities in patients with endometrial cancer. The interactions and pathways of molecules reported to have significant differential expression in endometrial cancers from Black and White patients were identified with Ingenuity Pathway Analysis. The majority of studies compared Black and White patients; however, limited data are available for other racial and ethnic groups. Reported differences that could account for the worse survival of Black endometrial cancer patients include more aggressive histopathologies and molecular alterations, including upregulation of molecules driving cell cycle progression, and p53 and HER2/NEU signaling. Several of these molecules are targeted by existing pharmaceuticals. These findings encourage further study and the development of race-specific treatment strategies.

Non-Coding RNAs as Prognostic Markers for Endometrial Cancer

Endometrial cancer (EC) has been classified over the years, for prognostic and therapeutic purposes. In recent years, classification systems have been emerging not only based on EC clinical and pathological characteristics but also on its genetic and epigenetic features. Noncoding RNAs (ncRNAs) are emerging as promising markers in several cancer types, including EC, for which their prognostic value is currently under investigation and will likely integrate the present prognostic tools based on protein coding genes. This review aims to underline the importance of the genetic and epigenetic events in the EC tumorigenesis, by expounding upon the prognostic role of ncRNAs.

LncRNA APTR Promotes Uterine Leiomyoma Cell Proliferation by Targeting ERα to Activate the Wnt/β-Catenin Pathway

The molecular mechanisms by which uterine leiomyoma (UL) cells proliferate are unclear. Long noncoding RNA (lncRNA) is reported to participate in the occurrence and development of gynecological cancers. We investigated the molecular mechanisms that lncRNA uses in UL. We found that lncRNA Alu-mediated p21 transcriptional regulator (APTR) showed higher expression in UL tumor tissues compared with that in normal uterine tissues. APTR induced cell proliferation and colony formation both in vitro and in vivo. The JASPAR database showed that APTR was likely interacted with ERα, and these molecules were identified via laser scanning confocal microscopy and RNA immunoprecipitation analysis. To verify the correlation between APTR and ERα, we overexpressed and underexpressed APTR and simultaneously expressed ERα. The results showed that APTR function was suppressed. APTR increased the expressions of the proteins in the Wnt pathway, and inhibiting ERα eliminated these responses. In conclusion, our data suggest that APTR promoted leiomyoma cell proliferation through the Wnt pathway by targeting ERα, suggesting a new role of APTR in the Wnt signaling pathway in UL.

LncRNA PCGEM1 contributes to malignant behaviors of glioma by regulating miR-539-5p/CDK6 axis

Background: Glioma, one of the most prevalent and aggressive cancers, is regulated by long noncoding RNAs (lncRNAs). This study aims to research the functional mechanism of lncRNA PCGEM1 involved in glioma progression.

Methods: Expression levels of PCGEM1, miR-539-5p and CDK6 were analyzed by qRT-PCR in NHA, U251, U87, and LN229 cells or glioma tissues. shRNAs were used to knock down PCGEM1 in U251 and LN229 cells. Kaplan-Meier curve and log rank test were utilized to examine survival rate. CCK8 (Cell Counting Kit-8) assay, colony formation assay and EdU staining were conducted to detect cell proliferation. Transwell assay was performed to evaluate cell migration and invasion. Luciferase reporter assay was conducted to assess RNA interaction between PCGEM1 and miR-539-5p. Nude mice were used for tumor xenograft assay.

Results: LncRNA PCGEM1 was upregulated in glioma tissues and tumor cell lines. PCGEM1 upregulation predicted unsatisfactory prognosis. PCGEM1 knockdown inhibited proliferation, colony formation, migration and invasion. PCGEM1 knockdown delayed tumor growth in vivo. PCGEM1 played as a competing endogenous RNA (ceRNA) for miR-539-5p to promote CDK6 expression. MiR-539-5p mimics repressed glioma progression while CDK6 overexpression reversed the roles of PCGEM1 knockdown.

Conclusion: PCGEM1 knockdown suppressed glioma progression through sponging miR-539-5p and regulating CDK6 expression, implying PCGEM1 as a potential therapeutic target.

Dual relationship between long non-coding RNAs and STAT3 signaling in different cancers: New insight to proliferation and metastasis

Uncontrolled growth and metastasis of cancer cells is an increasing challenge for overcoming cancer, and improving survival of patients. Complicated signaling networks account for proliferation and invasion of cancer cells that need to be elucidated for providing effective cancer therapy, and minimizing their malignancy. Long non-coding RNAs (lncRNAs) are RNA molecules with a length of more than 200 nucleotides. They participate in cellular events, and their dysregulation in a common phenomenon in different cancers. Noteworthy, lncRNAs can regulate different molecular pathways, and signal transducer and activator of transcription 3 (STAT3) is one of them. STAT3 is a tumor-promoting factors in cancers due to its role in cancer proliferation (cell cycle progression and apoptosis inhibition) and metastasis (EMT induction). LncRNAs can function as upstream mediators of STAT3 pathway, reducing/enhancing its expression. This dual relationship is of importance in affecting proliferation and metastasis of cancer cells. The response of cancer cells to therapy such as chemotherapy and radiotherapy is regulated by lncRNA/STAT3 axis. Tumor-promoting lncRNAs including NEAT1, SNHG3 and H19 induces STAT3 expression, while tumor-suppressing lncRNAs such as MEG3, PTCSC3 and NKILA down-regulate STAT3 expression. Noteworthy, upstream mediators of STAT3 such as microRNAs can be regulated by lncRNAs. These complicated signaling networks are mechanistically described in the current review.

Down-regulation of lncRNA PCGEM1 inhibits cervical carcinoma by modulating the miR-642a-5p/LGMN axis

LncRNA PCGEM1 (PCGEM1) has been reported to exert essential effects on the development and progress of various tumors, while the detailed effects and possible mechanisms of PCGEM1 in cervical carcinoma remain unknown. In the present study, PCGEM1 was over-expressed in cervical carcinoma cells as evidenced by real-time quantitative polymerase chain reaction (RT-qPCR) assay. Knockdown of PCGEM1 significantly repressed proliferation, migration, and invasion, while induced G1 arrest in cervical carcinoma cells. In addition, PCGEM1 was predicted to target miR-642a-5p by bioinformatics software, which was further confirmed by luciferase reporter assay. Besides, RT-qPCR assay indicated that miR-642a-5p expression was decreased in cervical carcinoma cells and knockdown of PCGEM1 could accelerate miR-642a-5p expression. Moreover, inhibition of miR-642a-5p partly abolished the functions of PCGEM1 knockdown on proliferation, cell cycle, migration and invasion of cervical carcinoma cells. Furthermore, miR-642a-5p could bind to the 3'-UTR of LGMN, which was over-expressed in the cervical carcinoma cells. Suppression of LGMN partly restored the functions of miR-642a-5p inhibitor on proliferation, cell cycle distribution, migration and invasion in the cervical carcinoma cells treated with the PCGEM1 shRNA. Taken together, our data indicated that knockdown of PCGEM1 inhibited proliferation, migration and invasion in cervical carcinoma by modulating the miR-642a-5p/ LGMN axis.

LncRNA PCGEM1 accelerates non-small cell lung cancer progression via sponging miR-433-3p to upregulate WTAP

Background

Non-small cell lung cancer (NSCLC) is one of the most common malignant tumors all over the world. In recent years, long non-coding RNAs (lncRNAs) have been proven to participate in the development of different cancers, including NSCLC. PCGEM1 prostate-specific transcript (PCGEM1) is the lncRNA which is associated with the progression of several cancers. Nevertheless, in NSCLC, the specific functions of PCGEM1 are not yet clear.

Methods

The real-time quantitative polymerase chain reaction (qPCR) was utilized to test the expression of PCGEM1 in NSCLC cells. Functional experiments, including cell Counting Kit-8 (CCK-8) assay, 5-ethynyl-2’-deoxyuridine (EdU) assay, flow cytometry analysis and transwell assays were utilized to estimate cell proliferation, migration, invasion and apoptosis. Meanwhile, RNA pull down assay and luciferase reporter assay were utilized to evaluate the correlation of miR-433-3p with PCGEM1 or WT1 associated protein (WTAP).

Result

PCGEM1 was highly expressed in NSCLC cells, while miR-433-3p was lowly expressed in NSCLC cells. PCGEM1 silencing or miR-433-3p overexpression inhibited cell proliferation, migration and invasion but accelerated cell apoptosis. MiR-433-3p was proven be sponged by PCGEM1. Besides, WTAP was the target of miR-433-3p and it accelerated the progression of NSCLC. In the end, rescue experiments indicated that overexpression of WTAP or knockdown of miR-433-3p reversed the inhibited roles of silencing PCGEM1 on cell behavior.

Conclusions

PCGEM1 accelerates NSCLC progression via sponging miR-433-3p to upregulate WTAP.

Non-coding RNAs, metabolic stress and adaptive mechanisms in cancer

Metabolic reprogramming in cancer describes the multifaceted alterations in metabolism that contribute to tumorigenesis. Major determinants of metabolic phenotypes are the changes in signalling pathways associated with oncogenic activation together with cues from the tumor microenvironment. Therein, depleted oxygen and nutrient levels elicit metabolic stress, requiring cancer cells to engage adaptive mechanisms. Non-coding RNAs (ncRNAs) act as regulatory elements within metabolic pathways and their widespread dysregulation in cancer contributes to altered metabolic phenotypes. Indeed, ncRNAs are the regulatory accomplices of many prominent effectors of metabolic reprogramming including c-MYC and HIFs that are activated by metabolic stress. By example, this review illustrates the range of ncRNAs mechanisms impacting these effectors throughout their DNA-RNA-protein lifecycle along with presenting the mechanistic roles of ncRNAs in adaptive responses to glucose, glutamine and lipid deprivation. We also discuss the facultative activation of metabolic enzymes by ncRNAs, a phenomenon which may reflect a broad but currently invisible level of metabolic regulation. Finally, the translational challenges associated with ncRNA discoveries are discussed, emphasizing the gaps in knowledge together with importance of understanding the molecular basis of ncRNA regulatory mechanisms.

The long noncoding RNA PCGEM1 promotes cell proliferation, migration and invasion via targeting the miR-182/FBXW11 axis in cervical cancer

Background

Cervical cancer (CC) is the fourth leading cause of cancer-associated death in women worldwide. Recently, long noncoding RNA (lncRNA) prostate cancer gene expression marker 1 (PCGEM1) has been demonstrated to involve in the initiation and progression of human cancers. However, to date, the clinical and functional significance of PCGEM1 expression in CC progression remains unknown.

Methods

qRT-PCR was performed to investigate PCGEM1 expression levels in CC tissues and cell lines. The effect of PCGEM1 on CC cells was assessed by gain- and loss-of-function assays. MS2-binding sequences-MS2-binding protein-based RIP assay (MS2-RIP), RNA pull-down and Luciferase reporter assays were performed to investigate the interaction between PCGEM1 and miR-182. The association between miR-182 and F-box and WD repeat domain containing 11 (FBXW11) was verified by luciferase reporter assay. The effect of PCGEM1 on the NF-κB and β-catenin/TCF signaling pathways was determined by luciferase reporter assay.

Results

Our present study showed that PCGEM1 was significantly upregulated in CC tissues and cell lines. Overexpression of PCGEM1 was correlated with advanced International Federation of Gynecology and Obstetrics (FIGO) stage, lymph node, distant metastasis and poor prognosis in CC patients. Functionally, PCGEM1 promoted cell proliferation, cell cycle progression, migration and invasion, while suppressed cell apoptosis in CC cells. Further mechanistic investigation revealed that PCGEM1 associated with miR-182 and suppressed its expression. PCGEM1 could act as a competing endogenous (ceRNA) of oncogene F-box and WD repeat domain containing 11 (FBXW11) for miR-182 in CC cells. Additionally, PCGEM1 was capable to activate the NF-κB and β-catenin/TCF signaling pathways, which was reversed by inhibition of FBXW11.

Conclusion

In conclusion, our findings demonstrated that PCGEM1-miR-182-FBXW11 axis play an important role in CC progression, and indicated a promising therapeutic target for CC patients.

Long non-coding RNAs and endometrial cancer

Endometrial cancer (EC) is one of the most common gynecologic malignancies. In spite of the advance in chemotherapy, radiotherapy or surgical techniques for EC in recent years, the survival rate of advanced stage EC patients remains unsatisfactory. Long non-coding RNAs (lncRNAs) are known as transcripts longer than 200 nucleotides exhibiting no or limited protein-coding potential. Growing evidence suggested lncRNAs may be a critical class of pervasive genes involved in cancer progression. However, the function and biological relevance between lncRNAs and EC remain not yet fully understood. Accumulating evidence has indicated that lncRNAs are dysregulated in EC, and closely related to tumorigenesis, metastasis and chemoresistance. In this review, we summarize the known regulation and functional roles of lncRNAs in EC. Besides, we will discuss the potential of lncRNAs as diagnostic biomarkers and therapeutic targets in EC.

Exploring lncRNA-Mediated Regulatory Networks in Endometrial Cancer Cells and the Tumor Microenvironment: Advances and Challenges

Recent studies have revealed both the promise and challenges of targeting long non-coding RNAs (lncRNAs) to diagnose and treat endometrial cancer (EC). LncRNAs are upregulated or downregulated in ECs compared to normal tissues and their dysregulation has been linked to tumor grade, FIGO stage, the depth of myometrial invasion, lymph node metastasis and patient survival. Tumor suppressive lncRNAs (GAS5, MEG3, FER1L4 and LINC00672) and oncogenic lncRNAs (CCAT2, BANCR, NEAT1, MALAT1, H19 and Linc-RoR) have been identified as upstream modulators or downstream effectors of major signaling pathways influencing EC metastasis, including the PTEN/PI3K/AKT/mTOR, RAS/RAF/MEK/ERK, WNT/β-catenin and p53 signaling pathways. TUG1 and TDRG1 stimulate the VEGF-A pathway. PCGEM1 is implicated in activating the JAK/STAT3 pathway. Here, we present an overview of the expression pattern, prognostic value, biological function of lncRNAs in EC cells and their roles within the tumor microenvironment, focusing on the influence of lncRNAs on established EC-relevant pathways. We also describe the emerging classification of EC subtypes based on their lncRNA signature and discuss the clinical implications of lncRNAs as valuable biomarkers for EC diagnosis and potential targets for EC treatment.

Hypoxia-induced LncRNA PCGEM1 promotes invasion and metastasis of gastric cancer through regulating SNAI1

PURPOSE

Hypoxia is an indispensable factor in the progression of metastasis. Hypoxia inducible factor-1α (HIF-1α), the core element in generating the hypoxia response, induces invasion and metastasis by promoting epithelial-mesenchymal transition (EMT). This study explored the underlying mechanism of hypoxia associated with the invasion and metastasis of gastric cancer (GC).

METHODS

Six methods were employed to assess the function of the long noncoding RNA (lncRNA) prostate cancer gene expression marker 1 (PCGEM1) including gene silencing, RT-PCR, the separation of nuclear and cytoplasmic fractions, scrape motility assay, transwell migration assay, and Western-blot.

RESULTS

LncRNA PCGEM1 was overexpressed in GC cells and tissues, and was induced by hypoxia in GC cells. Additional experiments confirmed that the knockdown of PCGEM1 significantly repressed the invasion and metastasis of GC cells. SNAI1, a key transcription factor of EMT, was regulated by PCGEM1. Overexpression of SNAI1 rescued the inhibition of PCGEM1-knockdown during the invasion and metastasis of GC cells. In addition, PCGEM1 and SNAI1 jointly affected the biomarkers of EMT.

CONCLUSION

Our findings indicated that PCGEM1 is a hypoxia-responsive lncRNA, and contributes to the invasion and metastasis of GC. The potential mechanism is attributed to the regulation of EMT by PCGEM1 and its influence on the expression of SNAI1.