Long non-coding RNA lncTCF7 activates the Wnt/β-catenin pathway to promote metastasis and invasion in colorectal cancer

Long non‑coding RNA signatures in breast cancer: Properties as biomarkers?

Breast cancer represents the most common type of cancer in females worldwide. The survival rates for breast cancer patients have been increasing since 1990. However, in 2023 breast cancer is still the second most common cause of malignancy-associated death in women. One decisive reason is the increase of treatment resistance and low therapy response. Therefore, new therapy targets and predictive markers for the response to treatment are needed. The present study analyzed the potential effects triggered by different breast cancer treatments on the transcriptional expression of 12 pre-selected long non-coding (lnc) RNAs and the proliferation markers Cyclin D1 and Ki-67 in six different breast cancer cell lines (BT-474, MDA-MB-231, BT-20, T-47D, SKBR-3 and MCF-7). The results revealed that lncRNA cytoskeleton regulator RNA may be an appropriate biomarker for the response to treatment with both epirubicin and gemcitabine (P<0.001). NF-ĸB interacting lnc RNA may be a marker for therapy response (P<0.001), while HOX transcript antisense RNA overexpression suggested resistance to treatment (P<0.001) with epirubicin. The transcriptional expression of lncRNA BC4 increased during treatment with epirubicin and gemcitabine, which indicated therapy response. Overall, the present data suggested that the aforementioned lncRNAs have a promising potential as biomarkers to detect early therapy response or resistance in and therefore should be analyzed in more detail.

A novel partnership between lncTCF7 and SND1 regulates the expression of the TCF7 gene via recruitment of the SWI/SNF complex

Long non-coding RNAs (lncRNAs) play key roles in cellular pathways and disease progression, yet their molecular mechanisms remain largely understudied. The lncRNA lncTCF7 has been shown to promote tumor progression by recruiting the SWI/SNF complex to the TCF7 promoter, activating its expression and the WNT signaling pathway. However, how lncTCF7 recruits SWI/SNF remains to be determined, and lncTCF7-specific binding partners are unknown. Using RNA-pulldown and quantitative mass spectrometry, we identified a novel interacting protein partner for lncTCF7, SND1, a multifunctional RNA binding protein that can also function as a transcription co-activator. Knockdown analysis of lncTCF7 and SND1 reveals that they are both required for the expression of TCF7. Chromatin immunoprecipitation assays suggest that both SND1 and lncTCF7 are required for recruiting the SWI/SNF chromatin remodeling complex, and these functions, in tandem, activate the expression of TCF7. Finally, using structural probing and RNA-pulldown of lncTCF7 and its subdomains, we highlight the potential binding region for SND1 in the 3'-end of lncTCF7. Overall, this study highlights the critical roles lncRNAs play in regulating gene expression and provides new insights into the complex network of interactions that underlie this process.

Targeting lncRNA/Wnt axis by flavonoids: A promising therapeutic approach for colorectal cancer

Despite the dramatic advances in our understanding of the etiology of colorectal cancer (CRC) in recent decades, effective therapeutic strategies are still urgently needed. Oncogenic mutations in the Wnt/β-Catenin pathway are hallmarks of CRC. Moreover, long non-coding RNAs (lncRNAs) as molecular managers are involved in the initiation, progression, and metastasis of CRC. Therefore, it is important to further explore the interaction between lncRNAs and Wnt/β-Catenin signaling pathway for targeted therapy of CRC. Natural phytochemicals have not toxicity and can target carcinogenesis-related pathways. Growing evidences suggest that flavonoids are inversely associated with CRC risk. These bioactive compounds could target carcinogenesis pathways of CRC and reduced the side effects of anti-cancer drugs. The review systematically summarized the progress of flavonoids targeting lncRNA/Wnt axis in the investigations of CRC, which will provide a promising therapeutic approach for CRC and develop nutrition-oriented preventive strategies for CRC based on epigenetic mechanisms. In the field, more epidemiological and clinical trials are required in the future to verify feasibility of targeting lncRNA/Wnt axis by flavonoids in the therapy and prevention of CRC.

Emerging role of lncRNAs in drug resistance mechanisms in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) originates in the squamous cell lining the mucosal surfaces of the head and neck region, including the oral cavity, nasopharynx, tonsils, oropharynx, larynx, and hypopharynx. The heterogeneity, anatomical, and functional characteristics of the patient make the HNSCC a complex and difficult-to-treat disease, leading to a poor survival rate and a decreased quality of life due to the loss of important physiologic functions and aggressive surgical injury. Alteration of driver-oncogenic and tumor-suppressing lncRNAs has recently been recently in HNSCC to obtain possible biomarkers for diagnostic, prognostic, and therapeutic approaches. This review provides current knowledge about the implication of lncRNAs in drug resistance mechanisms in HNSCC. Chemotherapy resistance is a major therapeutic challenge in HNSCC in which lncRNAs are implicated. Lately, it has been shown that lncRNAs involved in autophagy induced by chemotherapy and epithelial-mesenchymal transition (EMT) can act as mechanisms of resistance to anticancer drugs. Conversely, lncRNAs involved in mesenchymal-epithelial transition (MET) are related to chemosensitivity and inhibition of invasiveness of drug-resistant cells. In this regard, long non-coding RNAs (lncRNAs) play a pivotal role in both processes and are important for cancer detection, progression, diagnosis, therapy response, and prognostic values. As the involvement of more lncRNAs is elucidated in chemoresistance mechanisms, an improvement in diagnostic and prognostic tools could promote an advance in targeted and specific therapies in precision oncology.

Regulatory RNAs, microRNA, long-non coding RNA and circular RNA roles in colorectal cancer stem cells

The properties of cancer stem cells (CSCs), such as self-renewal, drug resistance, and metastasis, have been indicated to be responsible for the poor prognosis of patients with colon cancers. The epigenetic regulatory network plays a crucial role in CSC properties. Regulatory non-coding RNA (ncRNA), including microRNAs, long noncoding RNAs, and circular RNAs, have an important influence on cell physiopathology. They modulate cells by regulating gene expression in different ways. This review discusses the basic characteristics and the physiological functions of colorectal cancer (CRC) stem cells. Elucidation of these ncRNAs will help us understand the pathological mechanism of CRC progression, and they could become a new target for cancer treatment.

The Emerging role of EMT-related lncRNAs in therapy resistance and their application as biomarkers

Cancer is the world's second largest cause of death. The most common cancer treatments are surgery, radiation therapy, and chemotherapy. Drug resistance, epithelial-to-mesenchymal transition (EMT), and metastasis are all pressing issues in cancer therapy today. Increasing evidence showed that drug-resistant and EMT are co-related with each other. Indeed, drug-resistant cancer cells possess enhanced EMT and invasive ability. Recent researches have demonstrated lncRNAs (long noncoding RNAs) are noncoding transcripts, which play an important role in the regulation of EMT, metastasis, and drug resistance in different cancers. However, the relationships among lncRNAs, EMT, and drug resistance are still unclear. These effects could be exerted via several signaling pathways such as TGF-β, PI3K-AKT, and Wnt/β-catenin. Identifying the crucial regulatory roles of lncRNAs in these pathways and processes leads to the development of novel targeted therapies. We review the key aspects of lncRNAs associated with EMT and therapy resistance. We focus on the crosstalk between lncRNAs and molecular signaling pathways affecting EMT and drug resistance. Moreover, each of the mentioned lncRNAs could be used as a potential diagnostic, prognostic, and therapeutic biomarker for cancer. Although, there are still many challenges to investigate lncRNAs for clinical applications.

Differential Expression of Decorin in Metastasising Colorectal Carcinoma Is Regulated by miR-200c and Long Non-Coding RNAs

Decorin (DCN) is one of the matricellular proteins that participate in normal cells' function as well as in cancerogenesis. While its expression in primary tumours is well known, there is limited data about its expression in metastases. Furthermore, the post-transcriptional regulation of DCN is still questionable, although it is well accepted that it is an important mechanism of developing metastatic cancer. The aim of our study was to analyse the expression of DCN and its potential regulatory ncRNAs in metastatic colorectal carcinoma (CRC). Nineteen patients with metastatic CRC were included. Using qPCR, we analysed the expression of DCN, miR-200c and five lncRNAs (LUCAT1, MALAT1, lncTCF7, XIST, and ZFAS1) in lymph node and liver metastases in comparison to the invasive front and central part of a primary tumour. Our results showed insignificant upregulation of DCN and significant upregulation for miR-200c, MALAT1, lncTCF7 and ZFAS1 in metastases compared to the primary tumour. miR-200c showed a positive correlation with DCN, and the aforementioned lncRNAs exhibited a significant positive correlation with miR-200c expression in metastatic CRC. Our results suggest that DCN as well as miR-200c, MALAT1, lncTCF7 and ZFAS1 contribute to the development of metastases in CRC and that regulation of DCN expression in CRC by ncRNAs is accomplished in an indirect manner.

Bioinformatics Analysis of Prognostic Value of SPC24 in ccRCC and Pan-Cancer

Purpose

Clear cell renal cell carcinoma (ccRCC) is one of the most common diseases in the world, with high morbidity and mortality. Recent studies have revealed the important role of SPC24, a subunit of the Ndc80 complex, in the occurrence and development of carcinoma. However, the latent effect of SPC24 in the progress of ccRCC remains to be further explored. The intent of this research is to investigate whether SPC24 can be used as an index to predict the progression of ccRCC and to explore its relationship with the immune microenvironment and pan-cancer.

Materials and Methods

Based on data from public databases, we determined the expression level and clinical value of SPC24 in ccRCC and human pan-cancer. RT-qPCR analysis was carried out to detect the expression level of SPC24 in the OSRC/786O (human ccRCC cells) cell lines and HK2 (human normal kidney cells) cell line. The signal transduction pathways activated by different levels of SPC24 expression were explored by Gene Set Enrichment Analysis (GSEA), and the CIBERSORT algorithm was applied to analyze the relationship between infiltrating immune cells and SPC24 expression in ccRCC and pan-cancer tissues.

Results

SPC24 is overexpressed in ccRCC and several types of tumors, which is associated with poor prognosis. GSEA and CIBERSORT algorithms suggested that the high expression group of SPC24 enriched various pathways including immune-related pathways, and the several infiltrated immunocytes were related to the expression of SPC24.

Conclusion

Our study revealed that SPC24 is a prognostic factor in ccRCC related to immunomodulation and has generalized value in pan-cancer.

LncRNA TCF7 Promotes Epithelial Ovarian Cancer Viability, Mobility and Stemness via Regulating ITGB8

This study aimed to investigate the carcinogenic role of long non-coding RNA T-cell factor 7 (lnc-TCF7) in epithelial ovarian cancer (EOC). Lnc-TCF7 overexpression and shRNA plasmids were transfected into SKOV3 and OVCAR3 cells, followed by measurement of cell proliferation, migration, invasion, apoptosis, stemness, and mRNA profile (via microarray). Besides, lnc-TCF7 expression was measured in tumor and adjacent tissues from 76 EOC patients. Lnc-TCF7 was upregulated in EOC cell lines; its overexpression increased cell proliferation, migration, invasion, but decreased apoptosis and promoted CD44, CD133 expressions, CD44+CD133+ cell proportion, spheres formation efficiency and drug resistance to cisplatin in SKOV3 and OVCAR3 cells. Besides, lnc-TCF7 ShRNA exhibited opposite effects comparing with its overexpression. Microarray analysis revealed 267 mRNAs were modulated by lnc-TCF7 dysregulation, among which ITGB8 was the most dysregulated one, which was validated by subsequent western blot and RT-qPCR. Furthermore, ITGB8 overexpression not only induced proliferation, migration, invasion and stemness, but also attenuated the effect of lnc-TCF7 ShRNA on these functions in SKOV3 and OVCAR3 cells. In addition, lnc-TCF7 was upregulated in tumor tissues and correlated with higher pathological grade, tumor size, International Federation of Gynecology and Obstetrics (FIGO) stage and worse overall survival in EOC patients. Conclusively, lnc-TCF7 regulates multiple oncogenic pathways, promotes proliferation, migration, invasion, stemness via upregulating ITGB8. It also correlates with advanced tumor features and poor prognosis in EOC, implying its potential as a target for EOC treatment.

Uncovering the stability status of the reputed reference genes in breast and hepatic cancer cell lines

Accurate and reliable relative gene expression analysis via the Reverse Transcription-quantitative Real Time PCR (RT-qPCR) method strongly depends on employing several stable reference genes as normalizers. Utilization of the reference genes without analyzing their expression stability under each experimental condition causes RT-qPCR analysis error as well as false output. Similar to cancerous tissues, cancer cell lines also exhibit various gene expression profiles. It is crucial to recognize stable reference genes for well-known cancer cell lines to minimize RT-qPCR analysis error. In this study, we showed the expression level and investigated the expression stability of eight common reference genes that are ACTB, YWHAZ, HPRT1, RNA18S, TBP, GAPDH, UBC, and B2M, in two sets of cancerous cell lines. One set contains MCF7, SKBR3, and MDA-MB231 as breast cancer cell lines. Another set includes three hepatic cancer cell lines, including Huh7, HepG2, and PLC-PRF5. Three excel-based softwares comprising geNorm, BestKeeper, and NormFinder, and an online tool, namely RefFinder were used for stability analysis. Although all four algorithms did not show the same stability ranking of nominee genes, the overall results showed B2M and ACTB as the least stable reference genes for the studied breast cancer cell lines. While TBP had the lowest expression stability in the three hepatic cancer cell lines. Moreover, YWHAZ, UBC, and GAPDH showed the highest stability in breast cancer cell lines. Besides that, a panel of five nominees, including ACTB, HPRT1, UBC, YWHAZ, and B2M showed higher stability than others in hepatic cancer cell lines. We believe that our results would help researchers to find and to select the best combination of the reference genes for their own experiments involving the studied breast and hepatic cancer cell lines. To further analyze the reference genes stability for each experimental condition, we suggest researchers to consider the provided stability ranking emphasizing the unstable reference genes.

Noncoding RNAs as Promising Diagnostic Biomarkers and Therapeutic Targets in Intestinal Fibrosis of Crohn's Disease: The Path From Bench to Bedside

Fibrosis is a major pathway to organ injury and failure, accounting for more than one-third of deaths worldwide. Intestinal fibrosis causes irreversible and serious clinical complications, such as strictures and obstruction, secondary to a complex pathogenesis. Under the stimulation of profibrotic soluble factors, excessive activation of mesenchymal cells causes extracellular matrix deposition via canonical transforming growth factor-β/Smads signaling or other pathways (eg, epithelial-to-mesenchymal transition and endothelial-to-mesenchymal transition) in intestinal fibrogenesis. In recent studies, the importance of noncoding RNAs (ncRNAs) stands out in fibrotic diseases in that ncRNAs exhibit a remarkable variety of biological functions in modulating the aforementioned fibrogenic responses. In this review, we summarize the role of ncRNAs, including the emerging long ncRNAs and circular RNAs, in intestinal fibrogenesis. Notably, the translational potential of ncRNAs as diagnostic biomarkers and therapeutic targets in the management of intestinal fibrosis is discussed based on clinical trials from fibrotic diseases in other organs. The main points of this review include the following: • Characteristics of ncRNAs and mechanisms of intestinal fibrogenesis • Wide participation of ncRNAs (especially the emerging long ncRNAs and circular RNAs) in intestinal fibrosis, including transforming growth factor-β signaling, epithelial-to-mesenchymal transition/endothelial-to-mesenchymal transition, and extracellular matrix remodeling • Translational potential of ncRNAs in the diagnosis and treatment of intestinal fibrosis based on clinical trials from fibrotic diseases in other organs.

lncRNA transcription factor 7 is related to deteriorating clinical features and poor prognosis in multiple myeloma, and its knockdown suppresses disease progression by regulating the miR-203-mediated Jagged1-Notch1 signaling pathway

Multiple myeloma (MM) remains a challenge to treat, and its precise pathogenic mechanisms have not been fully clarified. The present study aimed to evaluate the relation between long non-coding RNA transcription factor 7 (lnc-TCF7) and clinical features, as well as the prognosis of patients with MM, and to determine the effects of lnc-TCF7-knockdown on the regulation (and regulatory mechanisms) of MM progression. lnc-TCF7 expression was detected in the bone marrow plasma cells of 86 patients with MM and 30 healthy controls. In patients with MM, the clinical data were collected, and event-free survival (EFS) and overall survival (OS) analyses were conducted. In vitro, lnc-TCF7 expression was detected in MM cell lines and normal bone marrow plasma cells. Using Roswell Park Memorial Institute 8226 cells, functional experiments were conducted following lnc-TCF7 short hairpin (sh)RNA transfection, and compensation experiments were performed after lnc-TCF7 shRNA transfection alone and in combination with a microRNA (miR)-203 inhibitor. lnc-TCF7 expression was increased in patients with MM compared with the healthy controls and was positively related to β-2-microglobulin expression and International Staging System stage, while negatively associated with complete response, EFS and OS. In vitro, lnc-TCF7 was upregulated in MM cells compared with normal bone marrow plasma cells, and its knockdown suppressed MM cell proliferation while promoting apoptosis. Compensation experiments showed that miR-203 inhibition promoted MM progression by regulating the Jagged1-Notch1 signaling pathway in lnc-TCF7-knockdown cells. In conclusion, increased lnc-TCF7 expression was related to deteriorating clinical features and prognosis, and lnc-TCF7-knockdown inhibited disease progression by regulating the miR-203-mediated Jagged1-Notch1 signaling pathway activation in MM.

The Emerging Landscape of Long Non-Coding RNAs in Colorectal Cancer Metastasis

Colorectal cancer (CRC) is one of the most common gastrointestinal cancers, with extremely high rates of morbidity and mortality. The main cause of death in CRC is distant metastasis; it affects patient prognosis and survival and is one of the key challenges in the treatment of CRC. Long non-coding RNAs (lncRNAs) are a group of non-coding RNA molecules with more than 200 nucleotides. Abnormal lncRNA expression is closely related to the occurrence and progression of several diseases, including cancer. Recent studies have shown that numerous lncRNAs play pivotal roles in the CRC metastasis, and reversing the expression of these lncRNAs through artificial means can reduce the malignant phenotype of metastatic CRC to some extent. This review summarizes the major mechanisms of lncRNAs in CRC metastasis and proposes lncRNAs as potential therapeutic targets for CRC and molecular markers for early diagnosis.

Long non-coding RNA T-cell factor 7 in multiple myeloma: A potential biomarker for deteriorated clinical features and poor prognosis

BACKGROUND

This study aimed to investigate the correlation of long non-coding RNA T-cell factor 7 (lnc-TCF7) with clinical features and prognosis in patients with multiple myeloma (MM).

METHODS

Totally, 216 newly diagnosed symptomatic MM patients and 60 healthy controls (HCs) were enrolled. Bone marrow samples were collected from patients before treatment and from HCs on donation to detect lnc-TCF7 expression in plasma cells by reverse transcription quantitative polymerase chain reaction. Besides, clinical response, progression-free survival (PFS), and overall survival (OS) of patients were assessed.

RESULTS

Lnc-TCF7 expression was increased in patients with MM compared with HCs. Lnc-TCF7 expression was highest in international staging system (ISS) stage III patients, followed by ISS stage II patients, and then ISS stage I patients, while lnc-TCF7 expression was similar in patients with different immunoglobulin subtypes and Durie-Salmon stages. Regarding chromosomal abnormalities, lnc-TCF7 expression positively correlated with t(4; 14) and Del(17p), whereas no correlation of lnc-TCF7 expression with t(14; 16), 1q21 amplification, Del(13q), or hyperdiploid was observed in patients with MM. Furthermore, lnc-TCF7 expression positively correlated with serum creatinine, beta-2-microglobulin, and lactate dehydrogenase in patients. Besides, lnc-TCF7 was negatively associated with complete response but not overall response rate in patients. Additionally, patients with lnc-TCF7 high expression exhibited shorter PFS and OS compared to patients with lnc-TCF7 low expression.

CONCLUSION

Lnc-TCF7 might have clinical value in aiding disease management and prognosis prediction of MM.

Long non-coding RNA (lncRNA) and epithelial-mesenchymal transition (EMT) in colorectal cancer: a systematic review

BACKGROUND

Colorectal cancer (CRC) is a leading cause of cancer-related death. Epithelial-mesenchymal transition (EMT) is a major process in tumor metastasis development. This systematic review aims to describe the role of long non-coding RNA (lncRNA) in EMT in CRC.

METHODS

The electronic databases, PubMed, Cochrane, and EMBASE, were searched from January1990 to June 2019 to identify studies examining lncRNA and their role in mediating EMT in CRC. Studies examining clinical specimens and/or in vitro experiments were included.

RESULTS

In 61 identified studies, 54 lncRNAs were increased in CRC compared to normal colorectal epithelium. Increased lncRNA expression was frequently associated with worse survival. Many lncRNAs mediate their effect through competitive endogenous RNA or transcription factor regulation. The ZEB1, 2/E-cadherin, Wnt/β-catenin signaling, and chromatin remodeling pathways are discussed in particular.

CONCLUSIONS

lncRNAs are major regulators of EMT and predictor adverse outcome in CRC patients. Future research must focus on delineating lncRNA function prior to potential clinical use.

LncRNA & Wnt signaling in colorectal cancer

The outlook for new therapeutic approaches is pivotal to ameliorate the deterioration caused by the abrogated Wnt signaling. Long non-coding RNAs (lncRNAs) are tiny molecules that have begun emerging as vital molecular manager for the regulation of various cellular processes at transcription and translation levels in the colorectal cancer (CRC). Targeting Wnt pathway with lncRNA seems a promising approach to eradicate CRC. However, little is known of their active role in commencing both apoptosis and proliferation in CRC. This article  reviews the importance of these molecules in the pathogenesis of CRC and also emphasizes on the development of new therapeutic strategies to cope with the Wnt mediated CRC.

Paxillin knockdown suppresses metastasis and epithelial‑mesenchymal transition in colorectal cancer via the ERK signalling pathway

Paxillin (PXN) is a cytoplasmic protein that plays an important role in regulating focal adhesion, cytoskeletal rearrangements and cell motility. The present study aimed to investigate the role of PXN in the metastasis of human colorectal cancer (CRC) and its possible mechanisms. Immunohistochemical staining of tissues from 102 surgical CRC patients revealed that high PXN expression was positively correlated with tumour‑node‑metastasis (TNM) stage, lymph node metastasis, distant metastasis, and recurrence at distant sites after radical surgery. In 24 cases of stage IV CRC, PXN expression in liver metastasis was higher than that in the matched primary tumour. The knockdown of PXN inhibited the proliferation, migration and invasion potential of SW480 cells in vitro and in vivo. Transmission electron microscopy revealed the effect of PXN on ultrastructural characteristics, observed mainly in microvilli and desmosomes. The downregulation of PXN decreased the activation of extracellular regulated protein kinase (ERK) and suppressed the epithelial‑mesenchymal transition (EMT) process. Following the downregulation of PXN, the addition of an ERK activator or inhibitor restored or further suppressed EMT, respectively, accompanied by corresponding changes in cell migration and invasion. Collectively, the present results confirmed the important role of PXN in CRC metastasis and revealed that PXN regulated EMT progression via the ERK signalling pathway. PXN may represent a future therapeutic strategy to prevent the EMT‑associated progression and invasion of CRC.

Noncoding RNAs: the shot callers in tumor immune escape

Immunotherapy, designed to exploit the functions of the host immune system against tumors, has shown considerable potential against several malignancies. However, the utility of immunotherapy is heavily limited due to the low response rate and various side effects in the clinical setting. Immune escape of tumor cells may be a critical reason for such low response rates. Noncoding RNAs (ncRNAs) have been identified as key regulatory factors in tumors and the immune system. Consequently, ncRNAs show promise as targets to improve the efficacy of immunotherapy in tumors. However, the relationship between ncRNAs and tumor immune escape (TIE) has not yet been comprehensively summarized. In this review, we provide a detailed account of the current knowledge on ncRNAs associated with TIE and their potential roles in tumor growth and survival mechanisms. This review bridges the gap between ncRNAs and TIE and broadens our understanding of their relationship, providing new insights and strategies to improve immunotherapy response rates by specifically targeting the ncRNAs involved in TIE.

LncRNA BANCR Promotes Pancreatic Cancer Tumorigenesis via Modulating MiR-195-5p/Wnt/β-Catenin Signaling Pathway

Long noncoding BRAF-activated noncoding RNA has been reported to be tightly associated with tumorigenesis and development in various types of cancers. However, the expression, biological function, and modulatory mechanism of BRAF-activated noncoding RNA in pancreatic cancer remained unclear. In the present work, we explored the carcinogenic activity and underlying mechanism of BRAF-activated noncoding RNA on pancreatic cancer in vitro. We identified that BRAF-activated noncoding RNA was upregulated in pancreatic cancer tissues and cell lines, and BRAF-activated noncoding RNA was related to tumor metastasis and stage. BRAF-activated noncoding RNA reinforces proliferation, invasion, and migration in PANC-1 and SW1990 cells. Moreover, miR-195-5p was downregulated in both PC tissues and cell lines. Our results based on luciferase reporter, RIP-Ago2 and qRT-PCR assays, showed that miR-195-5p was a direct target of BRAF-activated noncoding RNA. Furthermore, miR-195-5p inhibitor abrogated the effects of short-interfering BRAF-activated noncoding RNA on PANC-1 and SW1990 cell growth and invasion in vitro. We further identified that BRAF-activated noncoding RNA played a vital role in activating the Wnt/β-catenin pathway by sponging miR-195-5p. Collectively, our study showed that BRAF-activated noncoding RNA promotes pancreatic cancer tumorigenesis through miR-195-5p/Wnt/β-catenin axis may serve as a potential target for diagnostics and therapeutics in pancreatic cancer.

Combination of Inositol Hexaphosphate and Inositol Inhibits Liver Metastasis of Colorectal Cancer in Mice Through the Wnt/β-Catenin Pathway

Introduction

Colorectal cancer, one of the most common tumors, is mainly fatal because of the occurrence of liver metastasis. Inositol hexaphosphate (IP6) and inositol (INS) were found, both, in vitro and in vivo to play an anti-tumor effect, whereas the combination of IP6 and INS was more effective than IP6 or INS alone.

Materials and Methods

The inhibitory effects of IP6, INS and the combination of IP6+INS on tumor progression and liver metastasis of colorectal cancer were investigated in an orthotopic transplantation model of colorectal cancer. The tumor-bearing mice were selected by in vivo bioluminescence imaging and were treated with IP6, INS, and IP6 combined with INS, respectively. All mice were sacrificed after 6 weeks of treatment. The cancer development and metastasis were compared among the groups. The expression of genes related to the Wnt/β-catenin in the model was analyzed.

Results

The results demonstrated that liver metastasis was inhibited after treatment with IP6, INS, and IP6+INS. Compared to that of the M_G, survival period was extended, and tumor weight was lowered in IP6_G, INS_G, and IP6+INS_G. Besides, the liver metastatic area of mice in IP6+INS_G was relatively smaller than that in M_G, IP6_G, or INS_G. The results of RNA-seq analysis showed that the expressions of Wnt10b, Tcf7, and c-Myc were significantly downregulated in IP6+INS_G compared to that in M_G (P<0.05). Results of real-time PCR and Western blot showed that mRNA and protein expressions of β-catenin, Wnt10b, Tcf7, and c-Myc were significantly lower in IP6+INS_G compared to that in M_G (P<0.05).

Discussion

IP6+INS was more effective in inhibiting liver metastasis of colorectal cancer than IP6 or INS alone. The better inhibition effect may be accomplished through regulating the mutation of Wnt/β-catenin signaling pathway by inhibiting Wnt10b, Tcf7, β-catenin, and c-Myc from abnormally high expression.

Identifying Structural Domains and Conserved Regions in the Long Non-Coding RNA lncTCF7

Long non-coding RNA (lncRNA) biology is a rapidly growing area of study. Thousands of lncRNAs are implicated as key players in cellular pathways and cancer biology. However, the structure–function relationships of these novel biomolecules are not well understood. Recent structural studies suggest that lncRNAs contain modular structural domains, which play a crucial role in their function. Here, we hypothesized that such structural domains exist in lncTCF7, a conserved lncRNA implicated in the development and progression of several cancers. To understand the structure–function relationship of lncTCF7, we characterized its secondary structure using chemical probing methods. Our model revealed structural domains and conserved regions in lncTCF7. One of the modular domains identified here coincides with a known protein-interacting domain. The model reported herein is, to our knowledge, the first structural model of lncTCF7 and thus will serve to direct future studies that will provide fundamental insights into the function of this lncRNA.

LncRNA LUCAT1 facilitates tumorigenesis and metastasis of triple-negative breast cancer through modulating miR-5702

Triple-negative breast cancer (TNBC) is a subtype of aggressive breast cancer with high recurrence and poor survival. Emerging evidence has indicated that long non-coding RNAs (lncRNAs) play pivotal roles in the development and progression of multiple cancers. Although there are substantial studies revealing that lung cancer-associated transcript 1 (LUCAT1) functions as a tumor promotor in various human cancers, the molecular mechanism of LUCAT1 in TNBC remains largely to be explored. In our study, we identified that LUCAT1 expression was dramatically enhanced in TNBC samples and cells. High LUCAT1 expression was strongly associated with advanced stages and poor prognosis of TNBC. LUCAT1 contributed to TNBC development through accelerating cell proliferation, cell cycle progression and metastasis as well as attenuating cell apoptosis. Moreover, miR-5702 was proved to directly bind to LUCAT1 and be negatively modulated by LUCAT1. Knockdown of miR-5702 reversed the suppressing influences of LUCAT1 depletion on TNBC progression. In conclusion, it was the first investigation to shed light on the significant function and underlying regulatory mechanism of LUCAT1 in TNBC tumorigenesis. We validated that LUCAT1 induced tumorigenesis and metastasis of TNBC via miR-5702, which provided clues for improving the treatment of TNBC.

Linc01194 acts as an oncogene in colorectal carcinoma and is associated with poor survival outcome

Background

The incidence of colorectal cancer ranks among the top three malignant tumors, attributing to more than 50,000 deaths in the United States every year. Survival rate is directly correlated with TNM stage at diagnosis, and identifying the molecules involved in the cancer development process will provide directions to better investigate the mechanisms of colorectal cancer.

Materials and methods

Bioinformatics analysis of differentially expressed long noncoding RNAs (lncRNAs), survival analysis, cell proliferation assay, migration assay, and Western blot analysis were performed.

Results

Fifty-one lncRNAs were identified between the early stage and late-stage groups. In the survival analysis, we found that Linc01194 is correlated with poor survival of colon cancer patients. In addition, by suppressing the expression of Linc01194 in colon cancer cell lines, cell proliferation and migration were inhibited. Western blot showed that N-cadherin and vimentin were downregulated, whereas E-cadherin was upregulated indicating that the process of epithelial–mesenchymal transition (EMT) was restrained.

Conclusion

Linc01194 promotes the proliferation and migration ability of colon cancer cells by activating EMT. It acts as an oncogene in colorectal carcinoma and is associated with worse survival outcome.

Novel long noncoding RNA OTUD6B-AS1 indicates poor prognosis and inhibits clear cell renal cell carcinoma proliferation via the Wnt/β-catenin signaling pathway

BACKGROUND

The long noncoding RNA (lncRNA) OTUD6B antisense RNA 1 (OTUD6B-AS1) is oriented in an antisense direction to the protein-coding gene OTUD6B on the opposite DNA strand. TCGA database data show that the expression of the lncRNA OTUD6B-AS1 is downregulated and that OTUD6B-AS1 acts as an antioncogene in a variety of tumors. However, the expression and biological functions of the lncRNA OTUD6B-AS1 are still unknown in tumors, including clear cell renal cell carcinoma (ccRCC).

METHODS

The expression level of OTUD6B-AS1 was measured in 75 paired human ccRCC tissue and corresponding adjacent normal renal tissue samples. The correlations between the OTUD6B-AS1 expression level and clinicopathological features were evaluated using the chi-square test. The effects of OTUD6B-AS1 on ccRCC cells were determined via MTT assay, clone formation assay, transwell assay, and flow cytometry. Furthermore, the impact of OTUD6B-AS1 overexpression on the activation of the Wnt/β-catenin signaling pathway was investigated. Finally, ACHN cells with OTUD6B-AS1 overexpression were subcutaneously injected into nude mice to evaluate the influence of OTUD6B-AS1 on tumor growth in vivo.

RESULTS

In this study, we found that the expression of the lncRNA OTUD6B-AS1 was downregulated in ccRCC tissue samples and that patients with low OTUD6B-AS1 expression had shorter overall survival than patients with high OTUD6B-AS1 expression, which showed that the different expression level of OTUD6B-AS1 indirectly correlated with survival of patients. Lentivirus-mediated OTUD6B-AS1 overexpression significantly decreased the proliferation of ccRCC cells and promoted the apoptosis of the cells. Furthermore, OTUD6B-AS1 overexpression partly inhibited cell migration and invasion. The overexpression of OTUD6B-AS1 decreased the activity of the Wnt/β-catenin pathway and suppressed the expression of epithelial-to-mesenchymal transition (EMT)-related proteins (E-cadherin, N-cadherin and Snail) in ccRCC cells. In addition, compared with the parental ACHN cells, OTUD6B-AS1-overexpressing ACHN cells injected into nude mice exhibited decreased tumor growth in vivo.

CONCLUSIONS

Taken together, our findings present a road map for targeting the newly identified lncRNA OTUD6B-AS1 to suppress ccRCC progression in cell lines, and these results elucidate a novel potential therapeutic target for ccRCC treatment.

Long Noncoding RNA Plasmacytoma Variant Translocation 1 (PVT1) Promotes Colon Cancer Progression via Endogenous Sponging miR-26b

BACKGROUND Recently, long noncoding RNAs (lncRNAs) have received wide attention in the area of tumor progression. Dysregulation of lncRNAs has been shown to participated in colon cancer, a known malignant tumor. This study aimed to identify the way lncRNA PVT1 affects the progression of colon cancer. MATERIAL AND METHODS Both human colon cancer tissues and 30 paired adjacent normal tissue samples, as well as the colon cancer cells, were collected. Then quantitative real-time (qRT-PCR) was performed to detect the expression of lncRNA PVT1 and miR-26b. Furthermore, the role of PVT1 was determined by function assays such as cell proliferation assay, invasion assay, and wound healing assay. The mechanism was studied using western blot assay and luciferase assay. RESULTS We demonstrate that the expression of PVT1 was significantly higher in tumor tissue compared with the adjacent normal tissue with a lower expression of miR-26b. Moreover, PVT1 promoted tumor growth, migration, and invasion in vitro. In addition, further experiments revealed that miR-26b was a direct target of PVT1 and could inhibit cell migration, invasion, and proliferation in colon cancer. CONCLUSIONS Our results suggest that PVT1 could promote metastasis and proliferation of colon cancer via endogenous sponging and inhibiting the expression of miR-26b, which may highlight the significance of lncRNA PVT1 in colon cancer tumorigenesis.

The roles of Wnt/β-catenin signaling pathway related lncRNAs in cancer

Long noncoding RNAs (lncRNAs), with length of more than 200 nucleotides, are not translated into proteins but involved in multiple diverse diseases, especially tumorigenesis. The dysregulation of lncRNAs greatly contributes to the progression of various tumors through specific signaling pathways, including Wnt/β-catenin signaling pathway, which is associated with malignant features of tumors. The interactions between lncRNAs, which have specific expression characteristics in diverse cancer tissues, and Wnt/β-catenin signaling pathway, exhibit potential as novel biomarkers and therapeutic targets. In this review, we aim to present research findings on the roles of Wnt pathway-related lncRNAs and their effects on Wnt/β-catenin signaling to regulate tumorigenesis in different cancer types. Results may be used as basis to develop or improve strategies for treatment of different carcinomas.

1,25(OH)2D3 Attenuates IL-1β-Induced Epithelial-to-Mesenchymal Transition Through Inhibiting the Expression of lncTCF7

The activated form of vitamin D3, 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], regulates numerous cellular processes, including inhibition of cancer progression. IL-1β has been reported to facilitate cancer development, especially by inducing an epithelial-to-mesenchymal transition (EMT) in several malignant tumors. However, the underlying mechanism of 1,25(OH)2D3 and IL-1β in colorectal cancer (CRC) still remains largely unknown. To fill in this knowledge gap, we measured cell proliferation and invasion by CCK-8 and Transwell assays after stimulation with 1,25(OH)2D3 and IL-1β. E-cadherin and vimentin were chosen as markers of EMT measured by immunofluorescence, quantitative real-time PCR (qRT-PCR), and Western blot. The expression and function of the vitamin D receptor (VDR) was evaluated by Western blot and luciferase reporter assay. qRT-PCR and RNA-FISH were performed to detect the expression and location of lncTCF7 in vitro. The binding sites of VDR in the lncTCF7 promoter were confirmed by a chromatin immunoprecipitation assay. Based on the above experiments, we found that 1,25(OH)2D3 attenuates IL-1β-induced increased proliferation and invasion in colorectal cancer through enhancing VDR, which inhibits the expression of lncTCF7 by directly binding to its promoter region.