lncRNA DSCAM-AS1 facilitates the progression of endometrial cancer via miR-136-5p

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.

MiR-136-5p in cancer: Roles, mechanisms, and chemotherapy resistance

MicroRNAs (miRNAs) have emerged as important regulators of gene expression, and the deregulation of their activity has been linked to the onset and progression of a variety of human malignancies. Among these miRNAs, miR-136-5p has attracted significant attention due to its diverse roles in cancer biology. Mostly, miR-136-5p is downregulated in malignancies. It could inhibit viability, proliferation, migration, invasion and promote apoptosis of tumor cells. This review article provides a comprehensive overview of the current understanding of miR-136-5p in different sorts of human cancers: genital tumors, head and neck tumors, tumors from the digestive and urinary systems, skin cancers, neurologic tumors, pulmonary neoplasms and other cancers by discussing its molecular mechanisms, functional roles, and impact in chemotherapies. In conclusion, miR-136-5p could be a promising new biomarker and potential clinical therapeutic target.

DSCAM-AS1 promotes the development of prostate cancer

PURPOSE

The purpose of this study was to investigate the role of lncRNA DSCAM-AS1 in prostate cancer to find new therapeutic targets and promote the research progress of prostate cancer.

METHODS

RT-qPCR was used to detect DSCAM-AS1 expression in prostate cancer tissues, normal tissues, human normal prostate epithelial cells (RWPE), and four prostate cancer cell lines. The clinical and prognostic role of DSCAM-AS1 was evaluated by the Kaplan-Meier curve and chi-square test. Secondly, a dual luciferase reporter gene assay was used to study the regulatory mechanism between miR-338-3p and DSCAM-AS1. Finally, the roles of DSCAM-AS1 and miR-338-3p in prostate cancer cell proliferation and metastasis were explored by CCK-8 and Transwell assays.

RESULTS

It was found that DSCAM-AS1 upregulation could serve as a warning of deterioration and poor prognosis in prostate cancer patients, and that knockdown of DSCAM-AS1 expression inhibited the progression of prostate cancer cells. In addition, miR-338-3p, a target of DSCAM-AS1, was found to be down-regulated in prostate cancer cells and miR-338-3p knockdown could reverse the inhibitory effect of DSCAM-AS1 silencing on prostate cancer.

CONCLUSION

DSCAM-AS1 is up-regulated in prostate cancer and regulates the progression of prostate cancer cells by targeting miR-338-3p.

LncRNA linc01194 promotes the progress of endometrial carcinoma by up-regulating SOX2 through binding to IGF2BP1

OBJECTIVE

Endometrial carcinoma (EC) is one of the most common gynecological malignant tumors. Our study showed that long non-coding RNA (lncRNA) linc01194 plays an important role in EC. We explored the mechanism of lncRNA linc01194 in EC.

METHODS

The expression of lncRNA linc01194 was detected in The Cancer Genome Atlas database and starBase database. The potential targeted protein of linc01194 was predicted through the starBase database. To determine the role of linc01194 in EC, we downregulated or upregulated the level of linc01194 in EC cell lines and analyzed the cell behaviors and the changes of its potential target proteins.

RESULTS

The expression of linc01194 in EC tissues is higher than that in normal endometrial tissues. The knockdown of linc01194 inhibited the cell proliferation, invasion and migration and promoted the apoptosis of EC cells, while overexpression of linc01194 promoted cell proliferation, invasion and migration and inhibited the apoptosis of EC cells. The starBase database revealed that linc01194 could bind to insulin-like growth factor 2 binding protein 1 (IGF2BP1). Previous results showed that in EC, IGF2BP1 could promote the expression of sex-determining region Y-box 2 (SOX2) by promoting the stability of SOX2 mRNA. Our results showed that linc01194 regulate the expression of IGF2BP1 and SOX2.

CONCLUSION

Linc01194 can promote the expression of downstream protein SOX2 through binding to IGF2BP1, thus promoting the occurrence and development of EC.

miR-136-5p: A key player in human cancers with diagnostic, prognostic and therapeutic implications

MiRNAs have emerged as crucial modulators of the expression of their target genes, attracting significant attention due to their engagement in various cellular processes, like cancer onset and development. Amidst the extensive repertoire of miRNAs implicated in cancer, miR-136-5p has emerged as an emerging miRNA with diverse roles. Dysregulation of miR-136-5p has been proved in human cancers. Accumulating evidence suggests that miR-136-5p mainly functions as a tumor suppressor. These data proposed that miR-136-5p is engaged in the regulation of various cellular processes, like cell proliferation, migration, invasion, EMT, and apoptosis. In addition, miR-136-5p has demonstrated substantial potential as a prognostic and diagnostic marker in human cancers as well as an effective mediator in cancer chemotherapy. Furthermore, miR-136-5p was shown to be correlated with clinicopathological features of affected patients, proposing that it could be used for cancer staging and patient survival. Therefore, a comprehensive comprehension of the precise molecular basis governing miR-136-5p dysregulation in different cancers is vital for unraveling its therapeutic importance. Here, we have discussed the molecular basis of miR-136-5p as a potential tumor suppressor as well as its importance in cancer diagnosis, prognosis, and chemotherapy. Finally, we have discussed the challenge of using miRNAs as a therapeutic target as well as the prospect regarding the importance of miR-136-5p in human cancers.

Deciphering the mechanisms of action of progesterone in breast cancer

A practice-changing, randomized, controlled clinical study established that preoperative hydroxyprogesterone administration improves disease-free and overall survival in patients with node-positive breast cancer. This research perspective summarizes evidences from our studies that preoperative hydroxyprogesterone administration may improve disease-free and overall survival in patients with node-positive breast cancer by modulating cellular stress response and negative regulation of inflammation. Non-coding RNAs, particularly DSCAM-AS1, play a regulatory role in this process, along with the upregulation of the kinase gene SGK1 and activation of the SGK1/AP-1/NDRG1 axis. Progesterone-induced modification of the progesterone receptor and estrogen receptor genomic binding pattern is also involved in orchestrating estrogen signaling in breast cancer, preventing cell migration and invasion, and improving patient outcomes. We also highlight the role of progesterone in endocrine therapy resistance, which could lead to novel treatment options for patients with hormone receptor-positive breast cancer and for those who develop resistance to traditional endocrine therapies.

PVT1/miR-136/Sox2/UPF1 axis regulates the malignant phenotypes of endometrial cancer stem cells

Tumor stem cells (TSCs) are thought to contribute to the progression and maintenance of cancer. Previous studies have suggested that plasmacytoma variant translocation 1 (PVT1) has a tumor-promoting effect on endometrial cancer; however, its mechanism of action in endometrial cancer stem cells (ECSCs) is unknown. Here, we found that PVT1 was highly expressed in endometrial cancers and ECSCs, correlated with poor patient prognosis, promoted the malignant behavior and the stemness of endometrial cancer cells (ECCs) and ECSCs. In contrast, miR-136, which was lowly expressed in endometrial cancer and ECSCs, had the opposite effect, and knockdown miR-136 inhibited the anticancer effects of down-regulated PVT1. PVT1 affected miR-136 specifically binding the 3' UTR region of Sox2 by competitively "sponging" miR-136, thus positively saving Sox2. Sox2 promoted the malignant behavior and the stemness of ECCs and ECSCs, and overexpression Sox2 inhibited the anticancer effects of up-regulated miR-136. Sox2 can act as a transcription factor to positively regulate Up-frameshift protein 1 (UPF1) expression, thereby exerting a tumor-promoting effect on endometrial cancer. In nude mice, simultaneously downregulating PVT1 and upregulating miR-136 exerted the strongest antitumor effect. We demonstrate that the PVT1/miR-136/Sox2/UPF1 axis plays an important role in the progression and maintenance of endometrial cancer. The results suggest a novel target for endometrial cancer therapies.

LncRNAs signatures associated with cuproptosis predict the prognosis of endometrial cancer

Background: Endometrial cancer (UCEC) is the sixth most common cancer in women, and although surgery can provide a good prognosis for early-stage patients, the 5-year overall survival rate for women with metastatic disease is as low as 16%. Long non-coding RNAs (LncRNAs) are thought to play an important role in tumor progression. Cuproptosis is a recently discovered form of cell death in which copper binds directly to the lipoacylated component of the tricarboxylic acid (TCA) cycle. The aggregation of these copper-bound listed mitochondrial proteins and the loss of Fe-S cluster proteins trigger proteotoxic stress, which leads to cell death. Therefore, the aim of this work was to investigate the role of Cuproptosis-related LncRNAs signaling in clinical prognostic prediction and immunotherapy, as well as the relationship between tumor mutation burden. Methods: Genomic, clinical and mutational data of endometrial cancer patients were presented in the TCGA database, and cuproptosis-related genes obtained from related studies. Coexpression analysis and Cox regression analysis were used to construct prognostic features. Patients were divided into high risk group and low risk group, and then ROC, survival rate, risk curve, principal component analysis, independent prognostic analysis and clinical subgroup model validation were performed to observe the prognostic value of characteristics. Subsequently, the GO and genomic KEGG enrichment and immune-related functions of LncRNAs as well as the tumor mutation burden were analyzed. Results: In 548 UCEC case data, we identified five associated LncRNAs co-expressed with cuproptosis genes, and we found that high-risk patients had poorer overall survival (OS), progression-free survival (PFS), and higher mortality. Independent prognostic analysis, ROC showed that the LncRNAs associated with cuproptosis could accurately predict the prognosis of patients. Enrichment analysis revealed that the biological functions of LncRNAs were related to tumorigenesis. We also discovered suppression of immune-related functions in high-risk patients with oncogene mutations, higher tumor mutation burden in low-risk patients, and longer overall survival in patients with higher tumor mutation burden. Conclusion: The identification of five LncRNAs associated with cuproptosis can accurately predict the prognosis of patients with endometrial cancer, and may provide a new perspective for clinical application and immunotherapy.

Progesterone modulates the DSCAM-AS1/miR-130a/ESR1 axis to suppress cell invasion and migration in breast cancer

BACKGROUND

A preoperative-progesterone intervention increases disease-free survival in patients with breast cancer, with an unknown underlying mechanism. We elucidated the role of non-coding RNAs in response to progesterone in human breast cancer.

METHODS

Whole transcriptome sequencing dataset of 30 breast primary tumors (10 tumors exposed to hydroxyprogesterone and 20 tumors as control) were re-analyzed to identify differentially expressed non-coding RNAs followed by real-time PCR analyses to validate the expression of candidates. Functional analyses were performed by genetic knockdown, biochemical, and cell-based assays.

RESULTS

We identified a significant downregulation in the expression of a long non-coding RNA, Down syndrome cell adhesion molecule antisense DSCAM-AS1, in response to progesterone treatment in breast cancer. The progesterone-induced expression of DSCAM-AS1 could be effectively blocked by the knockdown of progesterone receptor (PR) or treatment of cells with mifepristone (PR-antagonist). We further show that knockdown of DSCAM-AS1 mimics the effect of progesterone in impeding cell migration and invasion in PR-positive breast cancer cells, while its overexpression shows an opposite effect. Additionally, DSCAM-AS1 sponges the activity of miR-130a that regulates the expression of ESR1 by binding to its 3'-UTR to mediate the effect of progesterone in breast cancer cells. Consistent with our findings, TCGA analysis suggests that high levels of miR-130a correlate with a tendency toward better overall survival in patients with breast cancer.

CONCLUSION

This study presents a mechanism involving the DSCAM-AS1/miR-130a/ESR1 genomic axis through which progesterone impedes breast cancer cell invasion and migration. The findings highlight the utility of progesterone treatment in impeding metastasis and improving survival outcomes in patients with breast cancer.

Excavation of Molecular Subtypes of Endometrial Cancer Based on DNA Methylation

Tumor heterogeneity makes the diagnosis and treatment of endometrial cancer difficult. As an important modulator of gene expression, DNA methylation can affect tumor heterogeneity and, therefore, provide effective information for clinical treatment. In this study, we explored specific prognostic clusters based on 482 examples of endometrial cancer methylation data in the TCGA database. By analyzing 4870 CpG clusters, we distinguished three clusters with different prognostics. Differences in DNA methylation levels are associated with differences in age, grade, clinical pathological staging, and prognosis. Subsequently, we screened out 264 specific hypermethylation and hypomethylation sites and constructed a prognostic model for Bayesian network classification, which corresponded to the classification of the test set to the classification results of the train set. Since the tumor microenvironment plays a key role in determining immunotherapy responses, we conducted relevant analyses based on clusters separated from DNA methylation data to determine the immune function of each cluster. We also predicted their sensitivity to chemotherapy drugs. Specific classifications of DNA methylation may help to address the heterogeneity of previously existing molecular clusters of endometrial cancer, as well as to develop more effective, individualized treatments.

DSCAM-AS1 Long Non-Coding RNA Exerts Oncogenic Functions in Endometrial Adenocarcinoma via Activation of a Tumor-Promoting Transcriptome Profile

Accumulating evidence suggests that lncRNA DSCAM-AS1 acts tumor-promoting in various cancer entities. In breast cancer, DSCAM-AS1 was shown to be the lncRNA being most responsive to induction by estrogen receptor α (ERα). In this study, we examined the function of DSCAM-AS1 in endometrial adenocarcinoma using in silico and different in vitro approaches. Initial analysis of open-source data revealed DSCAM-AS1 overexpression in endometrial cancer (EC) (p < 0.01) and a significant association with shorter overall survival of EC patients (HR = 1.78, p < 0.01). In EC, DSCAM-AS1 was associated with endometrial tumor promotor gene PRL and with expression of ERα and its target genes TFF1 and PGR. Silencing of this lncRNA by RNAi in two EC cell lines was more efficient in ERα-negative HEC-1B cells and reduced their growth and the expression of proliferation activators like NOTCH1, PTK2 and EGR1. DSCAM-AS1 knockdown triggered an anti-tumoral transcriptome response as revealed by Affymetrix microarray analysis, emerging from down-regulation of tumor-promoting genes and induction of tumor-suppressive networks. Finally, several genes regulated upon DSCAM-AS1 silencing in vitro were found to be inversely correlated with this lncRNA in EC tissues. This study clearly suggests an oncogenic function of DSCAM-AS1 in endometrial adenocarcinoma via activation of a tumor-promoting transcriptome profile.

LncRNA GATA3-AS1 promoted invasion and migration in human endometrial carcinoma by regulating the miR-361/ARRB2 axis

Endometrial carcinoma (EC) is a kind of fatal female malignancy. lncRNA GATA3-AS1 has been identified as an oncogene in various cancers. However, the functions and mechanisms of GATA3-AS1 in EC remain to be explored. Human EC tissues and four EC cell lines were used. Western blotting and quantitative real-time PCR (qRT-PCR) were used to evaluate the expression of GATA3-AS1, miR-361, and ARRB2. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were used to validate the interaction among GATA3-AS1, miR-361, and ARRB2. Flow cytometry, colony formation assay, scratch assay, and transwell assay were used to examine the cell apoptosis, proliferation, migration, and invasion of EC cells, respectively. In vivo tumor growth was monitored in nude mice. GATA3-AS1 and ARRB2 were upregulated while miR-361 was downregulated in human EC tissues and EC cells. GATA3-AS1 knockdown constrained cell proliferation, invasion, migration, and EMT while promoting the apoptosis of EC cells by upregulating miR-361. GATA3-AS1 negatively regulated miR-361 expression. ARRB2 was the direct target of miR-361 and could activate the Src/Akt pathway. In vivo, GATA3-AS1 knockdown suppressed tumor progression by upregulating the miR-361 expression. lncRNA GATA3-AS1 promoted EC invasion and migration by the miR-361/ARRB2 axis, which indicated that GATA3-AS1 might be a promising therapeutic option for advanced EC progression. KEY MESSAGES: GATA3-AS1 knockdown suppressed EC proliferation, invasion, and migration. GATA3-AS1 directly inhibited miR-361 as a ceRNA. MiR-361 knockdown reversed the tumor suppressive effect caused by GATA3-AS1 knockdown. MiR-361 bound to ARRB2 directly and suppressed its expression. The GATA3-AS1/miR-361/ARRB2 axis regulated EC cell proliferation, invasion, and migration.