Long noncoding RNA HEGBC promotes tumorigenesis and metastasis of gallbladder cancer via forming a positive feedback loop with IL-11/STAT3 signaling pathway

The regulatory relationship between transcription factor STAT3 and noncoding RNA

Signal transducer and activator of transcription 3 (STAT3), as a key node in numerous carcinogenic signaling pathways, is activated in various tumor tissues and plays important roles in tumor formation, metastasis, and drug resistance. STAT3 is considered a potential subtarget for tumor therapy. Noncoding RNA (ncRNA) is a special type of RNA transcript. Transforming from "junk" transcripts into key molecules involved in cell apoptosis, growth, and functional regulation, ncRNA has been proven to be closely related to various epithelial-mesenchymal transition and drug resistance processes in tumor cells over the past few decades. Research on the relationship between transcription factor STAT3 and ncRNAs has attracted increased attention. To date, existing reviews have mainly focused on the regulation by ncRNAs on the transcription factor STAT3; there has been no review of the regulation by STAT3 on ncRNAs. However, understanding the regulation of ncRNAs by STAT3 and its mechanism is important to comprehensively understand the mutual regulatory relationship between STAT3 and ncRNAs. Therefore, in this review, we summarize the regulation by transcription factor STAT3 on long noncoding RNA, microRNA, and circular RNA and its possible mechanisms. In addition, we provide an update on research progress on the regulation of STAT3 by ncRNAs. This will provide a new perspective to comprehensively understand the regulatory relationship between transcription factor STAT3 and ncRNAs, as well as targeting STAT3 or ncRNAs to treat diseases such as tumors.

LINC00115 promotes gastric cancer partly by the miR-212-5p/ATPAF1 axis

LncRNAs are known to be key regulators in the initiation and development of diverse cancers. Whether LINC00115 is involved in the regulation of gastric cancer (GC) progression remains unclear. Here, we aimed to show the function of LINC00115 in GC. RT-qPCR was used to measure gene expression in GC tissues and cells. Colony formation, EdU, TUNEL, and wound healing assays were used to analyze cellular processes in GC. The in vivo GC xenograft model was established. We observed that LINC00115 was highly expressed in GC. Functionally, silencing LINC00115 inhibited GC cell proliferation, and migration but facilitated GC apoptosis. Mechanistically, LINC00115 sponged miR-212-5p, while miR-212-5p targeted ATPAF1 in GC cells. Rescue assays showed ATPAF1 overexpression countervailed the inhibitory role of LINC00115 depletion in GC progression in vitro and in vivo. Overall, LINC00115 promoted GC progression by upregulating ATPAF1 via miR-212-5p.

MCF2L-AS1/miR-874-3p/STAT3 feedback loop contributes to lung adenocarcinoma cell growth and cisplatin resistance

Background

Long noncoding RNA (lncRNA) is widely acknowledged for its crucial role in the biological processes of various human cancers. MCF2L antisense RNA 1 (MCF2L-AS1) is a newly identified lncRNA, which remains unexplored in the context of cancer.

Methods

MCF2L-AS1 expression was examined using qRT-PCR analysis. The impact of MCF2L-AS1 on LUAD cell growth was assessed through CCK-8, colony formation, EdU, caspase-3 activity, TUNEL, Western blot, and transwell assays. The interaction between miR-874-3p and MCF2L-AS1 or STAT3 was confirmed by RIP, luciferase reporter, and RNA pull-down assays.

Results

Our study demonstrated the overexpression of MCF2L-AS1 in LUAD cells. Functionally, the silencing of MCF2L-AS1 hindered cell proliferation, migration, and invasion, while promoting cell apoptosis. Notably, the depletion of MCF2L-AS1 was associated with decreased cisplatin resistance. Mechanistically, MCF2L-AS1 was identified as an upstream gene of miR-874-3p, negatively regulating its expression. Following this, STAT3, the downstream target of miR-874-3p, was identified. Additionally, the expression of STAT3 was inversely related to miR-874-3p and positively regulated by MCF2L-AS1. A restoration assay suggested that MCF2L-AS1 promoted LUAD cell growth by sponging miR-874-3p and modulating STAT3 expression. Intriguingly, STAT3 was subsequently confirmed as a transcription factor that binds to the MCF2L-AS1 promoter, thereby enhancing its transcription.

Conclusions

The MCF2L-AS1/miR-874-3p/STAT3 feedback loop plays a significant role in LUAD cell growth and cisplatin resistance.

Identification of a basement membrane-related genes signature with immune correlation in bladder urothelial carcinoma and verification in vitro

BACKGROUND

Bladder urothelial carcinoma (BLCA) is the most common genitourinary cancer and the prognosis of patients is often poor. However, studies of basement membrane-related genes (BM-related genes) in BLCA are less reported. Therefore, we established a BM-related genes signature to explore their functional and prognostic value in BLCA.

METHODS

In this study, a BM-related genes signature was constructed by LASSO-Cox regression analysis, and then a series of bioinformatics methods was used to assess the accuracy and validity of the signature. We constructed a nomogram for clinical application and also screened for possible therapeutic drugs. To investigate the functions and pathways affected by BM-related genes in BLCA, we performed functional enrichment analyses. In addition, we analyzed the immune cell infiltration landscape and immune checkpoint-related genes in the high and low-risk groups. Finally, we confirmed the prognostic value of BM-related genes in BLCA in vitro.

RESULTS

Combining multiple bioinformatics approaches, we identified a seven-gene signature. The accuracy and validity of this signature in predicting BLCA patients were confirmed by the test cohort. In addition, the risk score was strongly correlated with prognosis, immune checkpoint genes, drug sensitivity, and immune cell infiltration landscape. The risk score is an independent prognostic factor for BLCA patients. Further experiments revealed that all seven signature genes were differentially expressed between BLCA cell lines and normal bladder cells. Finally, overexpression of LAMA2 inhibited the migration and invasion ability of BLCA cell lines.

CONCLUSIONS

In summary, the BM-related genes signature was able to predict the prognosis of BLCA patients accurately, indicating that the BM-related genes possess great clinical value in the diagnosis and treatment of BLCA. Moreover, LAMA2 could be a potential therapeutic target, which provides new insights into the application of the BM-related genes in BLCA patients.

LncRNA ASB16-AS1 accelerates cellular process and chemoresistance of ovarian cancer cells by regulating GOLM1 expression via targeting miR-3918

BACKGROUND

Reportedly, ovarian cancer (OC) is a major threat to women's health. Long non-coding RNA (lncRNA) ASB16-AS1 has been uncovered to participate in cancer progression. Nevertheless, the role of ASB16-AS1 in OC remains to be revealed.

PURPOSE

This study aimed to unveil the biological function of ASB16-AS1 and its underlying mechanisms in OC cells.

METHODS

QRT-PCR was done to test ASB16-AS1 expression in OC cells. Functional assays were performed to evaluate the malignant behaviors and cisplatin resistance of OC cells. Mechanistic analyses were done to investigate the regulatory molecular mechanism in OC cells.

RESULTS

ASB16-AS1 was found to be highly expressed in OC cells. ASB16-AS1 knockdown repressed proliferation, migration, and invasion of OC cells, while facilitating cell apoptosis. ASB16-AS1 was further validated to up-regulate GOLM1 through competitively binding with miR-3918. Moreover, miR-3918 overexpression was corroborated to suppress OC cell growth. Rescue assays further uncovered that ASB16-AS1 modulated the malignant processes of OC cells via targeting miR-3918/GOLM1 axis.

CONCLUSION

ASB16-AS1 facilitates the malignant processes and chemoresistance of OC cells via serving as miR-3918 sponge and positively modulating GOLM1 expression.

Exosomal LOC85009 inhibits docetaxel resistance in lung adenocarcinoma through regulating ATG5-induced autophagy

AIMS

This study aims at investigating the role of a neighbor long non-coding RNA (lncRNA) of HDAC4 (LOC85009) in docetaxel (DTX) resistance of lung adenocarcinoma (LUAD).

METHODS

RT-qPCR was used to analyze LOC85009 expression in DTX-resistant LUAD cells. In vitro and in vivo experiments were applied to detect the influence of LOC85009 on LUAD cell growth and xenograft tumor growth. DNA pull down assay, RNA pull down assay, ChIP assay, CoIP assay and RIP assay were performed to identify the direct interactions between factors.

RESULTS

LOC85009 was lowly-expressed in DTX-resistant LUAD cells. Functionally, LOC85009 overexpression inhibited DTX resistance and cell proliferation but triggered cell apoptosis. Moreover, we identified that LOC85009 was transferred from LUAD cells to DTX-resistant LUAD cells via exosomes. Exosomal LOC85009 inhibited DTX resistance, proliferation and autophagy while induced apoptosis in DTX-resistant cells. Additionally, we found that LOC85009 sequestered ubiquitin-specific proteinase 5 (USP5) to destabilize upstream transcription factor 1 (USF1) protein, thereby inactivating ATG5 transcription.

CONCLUSIONS

Exosomal LOC85009 inhibits DTX resistance through regulation of ATG5-induced autophagy via USP5/USF1 axis, suggesting that LOC85009 might be a potential target to reverse DTX resistance in the treatment of LUAD.

CERS6 antisense RNA 1 promotes colon cancer via upregulating mitochondrial calcium uniporter

BACKGROUND

Colon cancer (CC) belongs to a common cancer of digestive system. Long non-coding RNAs (lncRNAs) are dysregulated in numerous cancers and affect their development. The function of lncRNA CERS6 antisense RNA 1 (CERS6-AS1) in CC remains unclear.

MATERIALS AND METHODS

CERS6-AS1 expression in colon adenocarcinoma tissues and CC cell lines was assessed by The Cancer Genome Atlas database and quantitative real-time polymerase chain reaction analysis. The function of CERS6-AS1 in CC was analysed by 5-ethynyl-2'-deoxyuridine, colony formation, flow cytometry, terminal deoxynucleotidyl transferase dUTP nick end labelling, wound healing, Transwell and immunofluorescence assays. Mechanistic analyses including RNA pull down, RNA-binding protein immunoprecipitation and luciferase reporter assay revealed the interaction between RNAs.

RESULTS

CERS6-AS1 expression was aberrantly upregulated in colon adenocarcinoma tissues and CC cell lines. CERS6-AS1 knockdown inhibited CC cell malignant phenotypes and in vivo tumour growth. CERS6-AS1 served as the competing endogenous RNA of microRNA-16-5p in CC, and microRNA-16-5p inhibition partly rescued the effects of CERS6-AS1 depletion on CC development. Mitochondrial calcium uniporter was targeted by microRNA-16-5p. Mitochondrial calcium uniporter upregulation completely remedied the influence of CERS6-AS1 silencing in CC progression. Moreover, CERS6-AS1 enhanced the stability of mitochondrial calcium uniporter messenger RNA via recruiting RNA-binding protein embryonic lethal abnormal vision like 1.

CONCLUSION

CERS6-AS1 promotes the development of CC via upregulating mitochondrial calcium uniporter expression.

MiR-134-5p/Stat3 Axis Modulates Proliferation and Migration of MSCs Co-Cultured with Glioma C6 Cells by Regulating Pvt1 Expression

Mesenchymal stem cells (MSCs) are critical in regenerating tissues because they can differentiate into various tissue cells. MSCs interact closely with cells in the tissue microenvironment during the repair of damaged tissue. Although regarded as non-healing wounds, tumors can be treated by MSCs, which showed satisfactory treatment outcomes in previous reports. However, it is largely unknown whether the biological behaviors of MSCs would be affected by the tumor microenvironment. Exploring the truth of tumor microenvironmental cues driving MSCs tumor “wound” regeneration would provide a deeper understanding of the biological behavior of MSCs. Therefore, we mimicked the tumor microenvironment using co-cultured glioma C6 cells and rat MSCs, aiming to assess the proliferation and migration of MSCs and the associated effects of Stat3 in this process. The results showed that co-cultured MSCs significantly exhibited enhanced tumorigenic, migratory, and proliferative abilities. Both up-regulation of Stat3 and down-regulation of miR-134-5p were detected in co-cultured MSCs. Furthermore, miR-134-5p directly regulated Stat3 by binding to the sequence complementary to microRNA response elements in the 3′-UTR of its mRNA. Functional studies showed that both the migration and proliferation abilities of co-cultured MSCs were inhibited by miR-134-5p, whereas Stat3 gain-of-function treatment reversed these effects. In addition, Pvt1 was confirmed to be regulated by miR-134-5p through Stat3 and the suppression of Pvt1 reduced the migration and proliferation abilities of co-cultured MSCs. To sum up, these results demonstrate a suppressive role of miR-134-5p in tumor-environment-driven malignant transformation of rat MSCs through directly targeting Stat3, highlighting a crucial role of loss-of-function of miR-134-5p/Stat3 axis in the malignant transformation, providing a reference to the potential clinic use of MSCs.

Reiterating the Emergence of Noncoding RNAs as Regulators of the Critical Hallmarks of Gall Bladder Cancer

Gall bladder cancer (GBC) is a rare and one of the most aggressive types of malignancies, often associated with a poor prognosis and survival. It is a highly metastatic cancer and is often not diagnosed at the initial stages, which contributes to a poor survival rate of patients. The poor diagnosis and chemoresistance associated with the disease limit the scope of the currently available surgical and nonsurgical treatment modalities. Thus, there is a need to explore novel therapeutic targets and biomarkers that will help relieve the severity of the disease and lead to advanced therapeutic strategies. Accumulating evidence has correlated the atypical expression of various noncoding RNAs (ncRNAs), including circular RNAs (circRNAs), long noncoding RNAs (lncRNAs), microRNAs (miRNAs), and small nucleolar RNAs (snoRNA) with the increased cell proliferation, epithelial-mesenchymal transition (EMT), invasion, migration, metastasis, chemoresistance, and decreased apoptosis in GBC. Numerous reports have indicated that the dysregulated expression of ncRNAs is associated with poor prognosis and lower disease-free and overall survival in GBC patients. These reports suggest that ncRNAs might be considered novel diagnostic and prognostic markers for the management of GBC. The present review recapitulates the association of various ncRNAs in the initiation and progression of GBC and the development of novel therapeutic strategies by exploring their functional and regulatory role.

Knockdown of long noncoding RNA AC245100.4 inhibits the tumorigenesis of prostate cancer cells via the STAT3/NR4A3 axis

Aim: To explore the role and mechanism of long noncoding RNA AC245100.4 and NR4A3 in prostate cancer (PCa). Methods: RNA-sequencing analysis was used to detect the downstream genes of AC245100.4. A series of gain- and loss-of-function approaches were used to investigate the roles of AC245100.4 and NR4A3. RNA immunoprecipitation was performed to examine the interaction between AC245100.4 and STAT3. Results: AC245100.4 was significantly upregulated in PCa cells and tissues. Knockdown of AC21500.4 significantly inhibited the tumorigenesis of PCa cells. Mechanistically, AC245100.4 deregulated the transcription of NR4A3 via increasing p-STAT3, which acted as a transcriptional repressor of NR4A3. Conclusion: Knockdown of long noncoding RNA AC245100.4 inhibits the tumorigenesis of PCa cells via the STAT3/NR4A3 axis.

LncRNA PCAT6 activated by SP1 facilitates the progression of breast cancer by the miR-326/LRRC8E axis

Breast cancer is an aggressive malignancy with high morbidity in females worldwide. Extensive studies reveal that long noncoding RNAs (lncRNAs) are abnormally expressed and act as key regulators in various cancers, including breast cancer. In this work, we investigated the role and regulatory mechanism of lncRNA prostate cancer-associated transcript 6 (PCAT6) in breast cancer progression. Our findings revealed that PCAT6 was overexpressed in breast cancer tissues and cell lines. Furthermore, elevation of PCAT6 reflected an adverse prognosis of patients. Functional experiments indicated that PCAT6 knockdown hampered cell proliferation, facilitated apoptosis and cell cycle arrest in vitro, and inhibited tumor growth in vivo. We also found that the transcription factor SP1 could bind to the PCAT6 promoter and promoted its expression. Subsequently, it was verified that PCAT6 was a molecular sponge for microRNA-326 (miR-326), and the leucine-rich repeat containing the eight family member E (LRRC8E) was a direct target of miR-326. Rescue assays revealed that LRRC8E overexpression attenuated the suppressive effect of PCAT6 knockdown on cellular progression of breast cancer. In summary, this study demonstrated that SP1-activated PCAT6 promoted the malignant behaviors of breast cancer cells by regulating the miR-326/LRRC8E axis.

Role of lncRNAs in the Development of an Aggressive Phenotype in Gallbladder Cancer

Long non-coding RNAs are sequences longer than 200 nucleotides that are involved in different normal and abnormal biological processes exerting their effect on proliferation and differentiation, among other cell features. Functionally, lncRNAs can regulate gene expression within the cells by acting at transcriptional, post-transcriptional, translational, or post-translational levels. However, in pathological conditions such as cancer, the expression of these molecules is deregulated, becoming elements that can help in the acquisition of tumoral characteristics in the cells that trigger carcinogenesis and cancer progression. Specifically, in gallbladder cancer (GBC), recent publications have shown that lncRNAs participate in the acquisition of an aggressive phenotype in cancer cells, allowing them to acquire increased malignant capacities such as chemotherapy resistance or metastasis, inducing a worse survival in these patients. Furthermore, lncRNAs are useful as prognostic and diagnostic biomarkers since they have been shown to be differentially expressed in tumor tissues and serum of individuals with GBC. Therefore, this review will address different lncRNAs that could be promoting malignant phenotypic characteristics in GBC cells and lncRNAs that may be useful as markers due to their capability to predict a poor prognosis in GBC patients.

Keep your eyes peeled for long noncoding RNAs: Explaining their boundless role in cancer metastasis, drug resistance, and clinical application

Cancer metastasis and drug resistance are two major obstacles in the treatment of cancer and therefore, the leading cause of cancer-associated mortalities worldwide. Hence, an in-depth understanding of these processes and identification of the underlying key players could help design a better therapeutic regimen to treat cancer. Earlier thought to be merely transcriptional junk and having passive or secondary function, recent advances in the genomic research have unravelled that long noncoding RNAs (lncRNAs) play pivotal roles in diverse physiological as well as pathological processes including cancer metastasis and drug resistance. LncRNAs can regulate various steps of the complex metastatic cascade such as epithelial-mesenchymal transition (EMT), invasion, migration and metastatic colonization, and also affect the sensitivity of cancer cells to various chemotherapeutic drugs. A substantial body of literature for more than a decade of research evince that lncRNAs can regulate gene expression at different levels such as epigenetic, transcriptional, posttranscriptional, translational and posttranslational levels, depending on their subcellular localization and through their ability to interact with DNA, RNA and proteins. In this review, we mainly focus on how lncRNAs affect cancer metastasis by modulating expression of key metastasis-associated genes at various levels of gene regulation. We also discuss how lncRNAs confer cancer cells either sensitivity or resistance to various chemo-therapeutic drugs via different mechanisms. Finally, we highlight the immense potential of lncRNAs as prognostic and diagnostic biomarkers as well as therapeutic targets in cancer.

Long Noncoding RNA MLK7-AS1 Promotes Non-Small-Cell Lung Cancer Migration and Invasion via the miR-375-3p/YWHAZ Axis

Long noncoding RNAs act essential regulators in lung cancer tumorigenesis. Our research aimed to investigate the potential function and molecular mechanisms of MLK7-AS1 in NSCLC (non-small-cell lung cancer). QRT-PCR results indicated that the MLK7-AS1 expression level was upregulated in NSCLC cells and tissues. MLK7-AS1 strengthened cell migration and invasion in H1299 and A549 cells. Luciferase reporter assay found that MLK7-AS1 functioned as an endogenous sponge for miR-375-3p. Transwell assay results showed that miR-375-3p suppressed cell migration and invasion in H1299 and A549 cells. YWHAZ was confirmed as a target gene of miR-375-3p by Targetscan. YWHAZ overexpression promoted the invasion of H1299 and A549 cells. MLK7-AS1 upregulated YWHAZ expression and enhanced H1299 and A549 cell invasion by sponging miR-375-3p. MLK7-AS1 improved the metastasis ability of A549 in vivo. In conclusion, MLK7-AS1 was identified as a novel oncogenic RNA in NSCLC and can function as a potential therapeutic target for NSCLC treatment.

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.

LMCD1 antisense RNA 1 (LMCD1-AS1) potentiates thyroid cancer cell growth and stemness via a positive feedback loop of LMCD1-AS1/miR-1287-5p/GLI2

Background

LMCD1 antisense RNA 1 (LMCD1-AS1) is a certified oncogene in several tumour types. However, its role in thyroid cancer (THCA) remains unknown.

Methods

The expression level of LMCD1-AS1 in THCA cells and the normal control cell was measured by quantitative real-time polymerase chain reaction (qRT-PCR). The effects of LMCD1-AS1 knockdown on cell proliferation, migration and apoptosis were detected by colony formation assay, EdU assay, wound healing assay and TUNEL assay. Sphere formation assay was applied to assess sphere formation ability of THCA cells. Bioinformatics analysis and mechanism experiments, including ChIP assay, RIP assay and luciferase reporter assay were conducted to evaluate the downstream and upstream molecular mechanisms of LMCD-AS1.

Results

A marked up-regulation of LMCD1-AS1 in THCA cells relative to normal control cells was found. LMCD1-AS1 silencing suppressed proliferation and migration but induced apoptosis in THCA cells. Moreover, LMCD1-AS1 knockdown reduced the sphere formation capacity of THCA cells. The transcriptional factor GLI family zinc finger 2 (GLI2) binds to LMCD1-AS1, which contributed to LMCD1-AS1 up-regulation in THCA cells. Cytoplasmic LMCD1-AS1 sponged a shared microRNA between LMCD1-AS1 and GLI2. GLI2 was inhibited bymiR-1287-5p and disinhibited by LMCD1-AS1.

Conclusions

LMCD1-AS1exerts pro-tumorigenic function through sponging miR-1287-5p to elevate GLI2 expression in THCA development, constituting a feedback loop of LMCD1-AS1/miR-1287-5p/GLI2.

Long noncoding RNA PVT1 promoted gallbladder cancer proliferation by epigenetically suppressing miR-18b-5p via DNA methylation

Gallbladder cancer (GBC) accounts for 85–90% malignancies of the biliary tree worldwide. Considerable evidence has demonstrated that dysregulation of lncRNAs is involved in the progression of cancer. LncRNA PVT1 has been reported to play important roles in various cancers, but its role in gallbladder cancer remains unknown. In the present study, we found that PVT1 was upregulated in GBC tissues and cells, and its upregulation was related with poor prognosis in GBC patients. PVT1 promoted GBC cells proliferation in vitro and in vivo. Mechanistically, PVT1 recruited DNMT1 via EZH2 to the miR-18b-5p DNA promoter and suppressed the transcription of miR-18b-5p through DNA methylation. Moreover, HIF1A was proved to be the downstream target gene of miR-18b-5p and PVT1 regulated GBC cells proliferation via HIF1A. In conclusion, our studies clarified the PVT1/miR-18b-5p/HIF1A regulation axis and indicated that PVT1 could be a potential therapeutic target for GBC.

Identification of UBE2T as an independent prognostic biomarker for gallbladder cancer

Gallbladder cancer is the most common biliary tract malignant tumor, with unfavorable patient outcomes. The present study aimed to identify potential diagnostic or prognostic biomarkers for gallbladder cancer. To do so, differentially expressed genes in the gallbladder walls and tumor tissues of patients with gallbladder cancer were analyzed via microarray. Furthermore, a protein-protein interaction network was constructed and genes with a degree score >10 were selected as hub genes. As ubiquitin conjugating enzyme E2T (UBE2T) was considered to be a hub gene, its expression was assessed via reverse transcription-quantitative (RT-q)PCR and immunohistochemistry (IHC). In addition, the association between UBE2T expression and the clinicopathological characteristics of patients with gallbladder cancer was analyzed using the χ² test. Furthermore, all patients were divided into high- and low groups based on UBE2T expression level and overall survival analysis was performed. Univariate and multivariate Cox regression analyses were performed to determine whether UBE2T may serve as an independent risk factor for gallbladder cancer. The results demonstrated that UBE2T expression was upregulated in the gallbladder walls and tumor tissues of patients with gallbladder cancer. Furthermore, UBE2T expression level was confirmed to be upregulated following RT-qPCR, and results from IHC demonstrated that UBE2T was predominantly expressed in the cytoplasm of gallbladder cancer cells. In addition, high UBE2T expression level was associated with clinical stage, T classification, N classification and M classification. The results from Univariate and multivariate analyses indicated that UBE2T expression level may be considered as an independent risk factor for gallbladder cancer. Taken together, the findings from this study suggested that high UBE2T expression level may contribute to the poor prognosis of patients with gallbladder cancer, and that UBE2T may act as an independent prognostic biomarker for these patients.

Long Non-Coding RNAs in Biliary Tract Cancer-An Up-to-Date Review

The term long non-coding RNA (lncRNA) describes non protein-coding transcripts with a length greater than 200 base pairs. The ongoing discovery, characterization and functional categorization of lncRNAs has led to a better understanding of the involvement of lncRNAs in diverse biological and pathological processes including cancer. Aberrant expression of specific lncRNA species was demonstrated in various cancer types and associated with unfavorable clinical characteristics. Recent studies suggest that lncRNAs are also involved in the development and progression of biliary tract cancer, a rare disease with high mortality and limited therapeutic options. In this review, we summarize current findings regarding the manifold roles of lncRNAs in biliary tract cancer and give an overview of the clinical and molecular consequences of aberrant lncRNA expression as well as of underlying regulatory functions of selected lncRNA species in the context of biliary tract cancer.

LINC00961 inhibits the migration and invasion of colon cancer cells by sponging miR-223-3p and targeting SOX11

Long noncoding RNAs play essential roles in colon cancer tumorigenesis. This study aimed to explore the potential function and molecular mechanisms of LINC00961 in colon cancer. qPCR results showed that LINC00961 was downregulated in colon cancer cells and tissues. Functional assays demonstrated that LINC00961 suppressed the migration and invasion of colon cancer cells in vitro. LINC00961 functioned as an endogenous sponge for miR-223-3p in colon cancer cells. SOX11 was confirmed as a target gene of miR-223-3p. The effect of miR-223-3p on colon cancer cells was then investigated. MiR-223-3p inhibition enhanced their migration and invasion. The effect of SOX11 on colon cancer cells was studied. SOX11 overexpression inhibited the invasion of colon cancer cells. LINC00961 acted as an anti-oncogene and upregulated SOX11 expression by functioning as a miR-223-3p sponge. This research revealed the molecular mechanism of LINC00961 in colon cancer. LINC00961 might act as a potential diagnostic biomarker and therapeutic target for further clinical treatments.

The long non-coding RNA OLC8 enhances gastric cancer by interaction with IL-11

BACKGROUND

The gastric cancer (GC) represents a common malignancy especially in China. Long non-coding RNAs (lncRNAs) are critically involved in various types of cancer. However, the underlying mechanisms of OLC8 in gastric cancer are still largely unknown.

METHODS

The lncRNA profiling was used to identify novel lncRNAs associated with GC. The expression of OLC8 was quantified using qRT-PCR. Migration and viability assays were performed to evaluate the in vitro effects. Xenograft tumor models were conducted to investigate the in vivo oncogenic potential. RNA-seq was used to identify IL-11 as OLC8 binding partner.

RESULTS

In current study, we have identified a novel lncRNA termed OLC8. OLC8 was significantly overexpressed in gastric cancer specimens and cell lines. In vitro experiments showed that OLC8 facilitated migration and viability of MKN1 and AGS cells. As expected, in vivo experiments also confirmed an oncogenic role for OLC8. Mechanistic study indicated that OLC8 associated with IL-11 transcripts. The OLC8-IL-11 binding greatly impaired the degradation of IL-11 mRNAs. Not surprisingly, enhanced expression of IL-11 could increase STAT3 activation to favor gastric cancer development.

CONCLUSIONS

Our current research has identified OLC8 as a novel oncogenic lncRNA in IL-11/STAT3 signaling, and OLC8 may constitute a potential target for gastric cancer intervention.

Long noncoding RNAs as potential biomarkers and therapeutic targets in gallbladder cancer: a systematic review and meta-analysis

Background

Mounting evidence has shown that long noncoding RNAs (lncRNAs) can play a substantial role in gallbladder cancer (GBC) development as tumor promotors or suppressors, and their abnormal expression is relevant to GBC patient outcomes. We completed this systematic review and meta-analysis to explore the clinical significance and mechanisms of lncRNAs in GBC.

Methods

We conducted a comprehensive literature search and selected eligible records according to the inclusion and exclusion criteria. Hazard ratios (HRs) and odds ratios (ORs) were extracted or calculated to estimate the relationships of high lncRNA expression with GBC patient survival and clinical outcomes.

Results

Eighteen studies were identified as eligible for this systematic review and meta-analysis. Heterogeneity among HRs of overall survival (OS) was notably high (I² = 86.2%, p < 0.001). Subgroup analysis suggested that overexpression of lncRNAs in a group that is upregulated in GBC showed a significant association with poor OS (HR = 2.454, 95% CI 2.004–3.004, I² = 0%). Conversely, overexpression of lncRNAs in a downregulated group was markedly related to good OS (HR = 0.371, 95% CI 0.267–0.517, I² = 0%). High expression levels of lncRNA AFAP1-AS1, MALAT1 and ROR were positively correlated with tumor size. Expression of lncRNA LET, LINC00152 and HEGBC exhibited a positive correlation with high T status. LncRNA LINC00152, HEGBC, MALAT1 and ROR showed a marked correlation with positive lymph node metastasis (LNM), while lncRNA GCASPC, MEG3, LET and UCA1 had the opposite effect. High expression levels of lncRNA HEGBC, PAGBC, PVT1 and UCA1 predicted high tumor node metastasis (TNM) stages, while lncRNA LET, GCASPC and MEG3 indicated low TNM stages. We also summarized the mechanisms of lncRNAs in GBC.

Conclusion

Aberrant expression of several lncRNAs was indicative of the prognosis of GBC patients, and lncRNAs showed promise as biomarkers and therapeutic targets for GBC.

Emerging roles for Interleukin-11 in disease

Interleukin (IL)-11 belongs to the IL-6 family of cytokines, discovered over 30 years ago. While early studies focused on the ability of IL-11 to stimulate megakaryocytopoiesis, the importance of this cytokine to inflammatory disease and cancers is only just beginning to be uncovered. This review outlines recent advances in our understanding of IL-11 biology, and highlights the development of novel therapeutics with the potential for clinical targeting of signaling by this cytokine in multiple diseases.

Long noncoding RNA NPCCAT1 promotes nasopharyngeal carcinoma progression via upregulating YY1

Long noncoding RNAs (lncRNAs) are frequently implicated in various cancers. However, the significances of lncRNAs in nasopharyngeal carcinoma (NPC) are largely unclear. In this study, we identified a novel lncRNA nasopharyngeal carcinoma copy number amplified transcript-1 (NPCCAT1), whose expression is increased in NPC tissues compared with nasopharyngeal normal tissues. Furthermore, we found the genomic copy number of NPCCAT1 is amplified in NPC, which contributes to the upregulation of NPCCAT1 in NPC. Functional experiments demonstrated that overexpression of NPCCAT1 promotes NPC cell growth and migration in vitro and NPC tumor growth in vivo. Knockdown of NPCCAT1 suppresses NPC cell grow and migration. Mechanistically, we found that NPCCAT1 directly binds YY1 mRNA 5'UTR, promotes YY1 mRNA translation, and upregulates YY1 protein level. Gain-of-function and loss-of-function assays revealed that YY1 promoted NPC cell proliferation and migration. Moreover, rescue assays showed that depletion of YY1 attenuated the roles of NPCCAT1 overexpression in promoting NPC cell growth and migration in vitro and NPC tumor growth in vivo. Overall, our study identified NPCCAT1 as an oncogenic lncRNA which promotes NPC progression via upregulating YY1, and suggested that lncRNA NPCCAT1 may be a promising therapeutic target for NPC.