Colon Cancer-associated Transcript Research Articles

Knockdown of lncRNA CCAT1 enhances sensitivity of paclitaxel in prostate cancer via regulating miR-24-3p and FSCN1

ABSTRACTDrug resistance limits the efficacy of chemotherapy in human cancers. Previous studies reported that long noncoding RNA colon cancer-associated transcript 1 (CCAT1) regulated progression of prostate cancer (PCa). However, the potential role of CCAT1 in the sensitivity of paclitaxel (PTX) in PCa and its mechanism remain largely unknown. The PTX-resistant PCa cells were established in PC3 and DU145 cells by increasing concentrations of PTX. The expressions of CCAT1, microRNA-24-3p (miR-24-3p) and fascin1 (FSCN1) were measured by quantitative real-time polymerase chain reaction. The viability and apoptosis were detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay, flow cytometry and western blot, respectively. The interaction among CCAT1, miR-24-3p and FSCN1 was explored by luciferase activity, RNA immunoprecipitation, RNA pull-down and western blot, respectively. Results showed that the expressions of CCAT1 were up-regulated and miR-24-3p was down-regulated in PCa and PTX-resistant PCa cells (PC3-TXR and DU145-TXR). Knockdown of CCAT1 or overexpression of miR-24-3p inhibited survival rate, half maximal inhibitory concentration (IC50) of PTX but increased apoptosis in PC3-TXR and DU145-TXR cells after treatment of PTX. miR-24-3p was bound to CCAT1 and its abrogation reversed knockdown of CCAT1-mediated increase of PTX sensitivity in PC3-TXR and DU145-TXR cells. Moreover, FSCN1 restoration attenuated miR-24-3p-mediated inhibition of PTX resistance. Besides, FSCN1 level was enhanced in PCa and PTX-resistant PCa cells and regulated by CCAT1 and miR-24-3p. Our data suggested interference of CCAT1 contributed to PTX sensitivity in PCa by regulating miR-24-3p and FSCN1, indicating a novel avenue for treatment of PCa through regulating chemoresistance.

CCAT2 contributes to hepatocellular carcinoma progression via inhibiting miR-145 maturation to induce MDM2 expression.

Long noncoding RNA colon cancer-associated transcript 2 (CCAT2) has been recently found to function as an oncogene in hepatocellular carcinoma (HCC). However, the mechanisms of CCAT2 in HCC development remain to be further explored. In the present study, we found that CCAT2 was abnormally upregulated in HCC cells and tissue specimens, exhibiting an inverse correlation with microRNA (miR)-145 expression. Mechanistic investigation showed that CCAT2 selectively blocked miR-145 processing, leading to decreased mature miR-145 presence. Both the in vitro and in vivo effects of CCAT2 knockdown on the proliferation and metastasis of HCC cells were reversed by miR-145 inhibitor, indicating that miR-145 modulation accounts for CCAT2-meditated HCC progression. Furthermore, miR-145 mimic dramatically suppressed HCC cells' proliferation and metastasis, revealing a tumor suppressor role of miR-145 in HCC. Mechanistically, MDM2 was predicted to be a potential target of miR-145. The luciferase and western blot assay demonstrated that miR-145 mimic largely inhibited MDM2 3'-untranslated region luciferase activity and MDM2 expression, followed by the upregulation of p53/p21 expression. Finally, the coexpression of MDM2 in miR-145 mimic-transfected HCC cells was able to largely compromise the inhibitory effects of miR-145 mimic on HCC cells' proliferation and metastasis in vitro and tumor formation in a xenograft model, confirming MDM2 is the critical mediator of miR-145 in HCC. In summary, our findings indicated that CCAT2 selectively blocks the miR-145 maturation process and plays an oncogene in HCC. Furthermore, a novel CCAT2/miR-145/MDM2 axis was revealed in HCC development and might provide a new target in the molecular treatment of HCC.

LncRNA CCAT1 Acts as a MicroRNA-218 Sponge to Increase Gefitinib Resistance in NSCLC by Targeting HOXA1

Long non-coding RNA (lncRNA) colon cancer-associated transcript-1 (CCAT1) has been reported to play important roles in the development and progression of multiple human malignancies. However, the functional role and molecular mechanism of CCAT1 on gefitinib resistance in non-small cell lung cancer (NSCLC) are largely unclear. The aim of this study is to explore the roles of CCAT1 on gefitinib resistance in NSCLC and to explore the underlying mechanisms. The quantitative real-time PCR (qRT-PCR) analysis was to investigate the expression pattern of CCAT1 in gefitinib-resistant NSCLC patient tissues and cell lines, and then the effects of CCAT1 on gefitinib resistance of NSCLC in vitro and in vivo. Furthermore, bioinformatics online program predictions and luciferase reporter assay were used to validate the association of CCAT1 and miR-218 in NSCLC cells. In this study, CCAT1 was observed to be upregulated in gefitinib-resistant patient tissues and cell lines. In vitro and in vivo experiments demonstrated that CCAT1 knockdown impaired cell proliferation and promoted the gefitinib-induced cell apoptosis. Furthermore, we demonstrated that CCAT1 acts as a sponge for miR-218, and verified that HOXA1 is a novel target of miR-218. These results suggest that CCAT1 may serve as a promising therapeutic target for the treatment of epidermal growth factor receptor (EGFR) plus NSCLC patients.

Silencing of Long Non-Coding RNA Colon Cancer-Associated Transcript 2 Inhibits the Growth and Metastasis of Gastric Cancer Through Blocking mTOR Signaling.

PurposeThis study aimed to evaluate the specific role of colon cancer-associated transcript 2 (CCAT2) on gastric cancer (GC), and reveal the potential regulatory mechanism relating to mammalian target of rapamycin (mTOR) signaling.MethodsThe expression of CCAT2 was detected in GC tissues and cells by quantitative real-time PCR (qRT-PCR), and its relation with the pathologic characteristics of GC patients was analyzed. HGC-27 and SGC-7901 cells were transfected with siRNA-CCAT2 to silence CCAT2, and HGC-27 cells were then treated with an mTOR agonist Leucine (Leu) to activate mTOR signaling. The cell proliferation was evaluated by cell viability and colony formation. The cell cycle and apoptosis, and the migration and invasion abilities were detected by Flow cytometry, and Transwell assay, respectively. The expression of PCNA (proliferation marker), Snail, N-cadherin, E-cadherin (invasion markers), P53, Caspase-8, Bcl-2 (apoptosis markers), LC3-II/LC3-I, ATG3, p62 (autophagy makers), phosphorylated mTOR (p-mTOR), p-AKT, and p-p70S6K (mTOR signaling markers) were detected by Western blot.ResultsCCAT2 was upregulated in GC tissues and cells, and positively associated with the maximum tumor diameter, lymphatic metastasis, TNM staging, and low overall survival rate (P < 0.05). siRNA-CCAT2 transfection significantly inhibited the viability, colony formation, and migration and invasion abilities, blocked the cell cycle in G0/G1 phase, and promoted the apoptosis and autophagy of SGC-7901 and HGC-27 cells (P < 0.05). In addition, siRNA-CCAT2 transfection significantly upregulated P53, Caspase-8, LC3-II/LC3-I and ATG3, and downregulated PCNA, Bcl-2, p62, p-mTOR, p-AKT and p-p70S6K in SGC-7901 and HGC-27 cells (P < 0.05). siRNA-CCAT2 reversed the tumor-promoting effect of mTOR signaling activation on HGC-27 cells (P < 0.05).ConclusionSilencing of CCAT2 inhibited the proliferation, migration and invasion, and promoted the apoptosis and autophagy of GC cells through blocking mTOR signaling.

Hyperoside exhibits anticancer activity in non‑small cell lung cancer cells with T790M mutations by upregulating FoxO1 via CCAT1.

Acquired epidermal growth factor receptor (EGFR) T790M mutation is the most common mechanism that accounts for EGFR‑TKI (tyrosine kinase inhibitor) resistance of non‑small cell lung cancer (NSCLC). High expense and acquired resistance weaken support for the use of osimertinib for T790M‑positive NSCLC treatment, and limit the efficacy and application of this drug. Hyperoside, a flavonol glycoside compound, extracted from Hypericum perforatum, has been reported to inhibit the growth of a variety of tumors. The present study aimed to investigate the role of hyperoside in treating NSCLC with T790M mutations, and to elucidate the underlying molecular mechanisms. Cell viability assays, apoptosis analysis, reverse transcription‑quantitative PCR, western blot analysis, animal experiments and immunohistochemistry were performed to examine the anticancer activity of hyperoside. Hyperoside inhibited the proliferation and induced the apoptosis of T790M‑positive NSCLC cells. Hyperoside upregulated forkhead box proteinO1 (FoxO1) expression and downregulated the level of long non‑coding RNA (lncRNA) colon cancer associated transcript1 (CCAT1) in T790M‑positive NSCLC cells. In the invivo study, hyperoside inhibited the growth of T790M‑positive NSCLC xenografts. In conclusion, hyperoside inhibited proliferation and induced apoptosis by upregulating FoxO1 via CCAT1 in T790M‑positive NSCLC both invitro and invivo, suggesting that hyperoside is a novel candidate for T790M‑positive NSCLC treatment.

The regulation and interaction of colon cancer-associated transcript-1 and miR7-5p contribute to the inhibition of SP1 expression by solamargine in human nasopharyngeal carcinoma cells.

Nasopharyngeal carcinoma (NPC) is a common head and neck malignancy with higher incidence in Southern China and Southeast Asia. Solamargine (SM), a steroidal alkaloid glycoside, has been shown to have anticancer properties. However, the underlying mechanism involved remains undetermined. In this study, we showed that SM inhibited the growth of NPC cells. Mechanistically, we found that solamargine decreased lncRNA colon cancer‐associated transcript‐1 (CCAT1) and increased miR7‐5p expression. There was a reciprocal interaction of CCAT1 and miR7‐5p. In addition, SM inhibited the expression of SP1 protein and promoter activity, which was strengthened by miR7‐5p mimics and inhibited by overexpressed CCAT1. MiR7‐5p could bind to 3'‐UTR of SP1 and attenuated SP1 gene expression. Exogenously expressed SP1 feedback resisted SM‐increased miR7‐5p expression and more importantly reversed SM‐inhibited growth of NPC cells. Finally, SM inhibited NPC tumor growth in vivo. Collectively, our results show that SM inhibits the growth of NPC cells through reciprocal regulation of CCAT1 and miR7‐5p, followed by inhibition of SP1 gene expression in vitro and in vivo. The interregulation and correlation among CCAT1, miR7‐5p and SP1, and the feedback regulatory loop unveil the novel molecular mechanism underlying the overall responses of SM in anti‐NPC.

LncRNA CCAT1/miR-490-3p/MAPK1/c-Myc positive feedback loop drives progression of acute myeloid leukaemia

Acute myeloid leukaemia (AML) is a frequently diagnosed malignancy in adults. Long non-coding RNA (lncRNA) colon cancer-associated transcript 1 (CCAT1) has been well known to play vital roles in multiple malignancies including AML. Unfortunately, the detailed mechanism of CCAT1 in AML progression remains obscure. In this study, we demonstrated that CCAT1 was up-regulated in AML samples while its target, miR-490-3p, was relatively down-regulated. CCAT1 markedly increased viability and metastasis of AML cells, while miR-490-3p had opposite effects. CCAT1 could specifically bind to miR-490-3p and reduce its expression and activity, and MAPK1 was a target gene of miR-490-3p. Overexpressed CCAT1 could induce MAPK1 expression and c-Myc reciprocally increased CCAT1 expression. Our data implied that miR-490-3p could be a novel therapeutic target for AML, and highlights the crucial role of CCAT1/miR-490-3p/MAPK1/c-Myc positive feedback loop in AML progression.

LncRNA CCAT2 promotes radiotherapy resistance for human esophageal carcinoma cells via the miR‑145/p70S6K1 and p53 pathway.

The long non‑coding RNA colon cancer‑associated transcript2 (CCAT2) is abnormally expressed in various types of malignant tumor tissues and considered to be an oncogene, including for esophageal cancer (EC). Radiotherapy is an important and widely used cancer treatment. However, some patients with EC do not respond to radiotherapy. This study was designed to investigate effects of CCAT2 expression on radiotherapy dynamics for ECcells and to explore underlying molecular mechanisms. Reverse transcription‑quantitative PCR was used to measure CCAT2 expression in EC tissues, normal esophageal mucosa, ECcells and normal human esophageal epithelial cells. TUNEL assays were used to assess the effect of CCAT2 on X‑ray‑induced apoptosis of ECcells. Protein expression was detected by western blot. CCAT2 was highly expressed in EC tissues and ECcells, and was negatively associated with radiotherapy efficacy in patients with EC. Invitro, knockdown of CCAT2 enhanced radiosensitivity of ECcells and promoted apoptosis by increasing Bax/Bcl2 and active‑caspase3/caspase3 following X‑ray treatment. In addition, CCAT2 negatively regulated miR‑145 and P70 ribosomal protein S6 kinase1 (p70S6K1) expression, and inhibited phosphorylation of Akt, ERK and p70S6K1 in ECcells. After X‑ray treatment, CCAT2 negatively regulated protein levels of p53, P21 and c‑Myc. These results showed that CCAT2 promoted the radiotherapy resistance of ECcells via negative regulation of the miR‑145/p70S6K1 and the p53 signaling pathways and associated elements may be potential targets for improving the sensitivity of EC radiotherapy.

Expression profile analysis of two antisense lncRNAs to improve prognosis prediction of colorectal adenocarcinoma

BackgroundLong noncoding RNAs (lncRNAs) are involved in different pathogenesis pathways including cancer pathogenesis. The adenoma-carcinoma pathway in colorectal cancer may involve the aberrant and variable gene expression of regulatory RNAs. This study was conducted to analyse the expression and prognosis prediction ability of two natural antisense transcripts, protein kinase C theta antisense RNA 1 (PRKCQ-AS1), and special AT-rich sequence binding protein 1 antisense RNA 1 (SATB1-AS1) in colorectal low-grade adenoma, advanced adenoma, and adenocarcinomas.MethodsIn this study, from two RNA-seq analyses of CCAT1-ko cells and colorectal carcinoma biopsies having diminished and increased levels of CCAT1 transcription, respectively, we nominated two antisense lncRNAs of PRKCQ-AS1 and SATB1-AS1. Samples from colorectal low-grade adenomas, advanced adenomas, adenocarcinomas, and adjacent tissue were subjected to RT-qPCR to determine the expression of PRKCQ-AS1, SATB1-AS1 along with colon cancer-associated transcript 1 (CCAT1) and cMYC. In addition, we used different bioinformatics analyses and webservers (including GEPIA 2, TCGA, and CancerMine) to elucidate the prognosis prediction value, the expression correlation of sense–antisense pair of genes, and the expression profile of these antisense transcripts at the presence or absence of mutations in the driver genes, or the corresponding sense genes.ResultsPRKCQ-AS1 showed a wide range of expression levels in colorectal adenoma, advanced adenoma, and adenocarcinoma. Upregulation of PRKCQ-AS1 was related to a significant decrease in survival of colorectal cancer (CRC) patients. The expression levels of PRKCQ-AS1 and PRKCQ were strong and significantly concordant in normal and cancerous colorectal tissues. While SATB1-AS1 showed a wide range of expression in colorectal adenoma, advanced adenoma, and adenocarcinoma as well, its expression was not related to a decrease in survival of CRC patients. The expression levels of SATB1-AS1 and SATB1 (the sense gene) were not strong in normal colorectal tissues. In addition, where SATB1 gene was mutated, the expression of SATB1-AS1 was significantly downregulated.ConclusionsWe found the expression of PRKCQ-AS1 and SATB1-AS1 at a given stage of CRC very variable, and not all biopsy samples showed the increased expression of these antisense transcripts. PRKCQ-AS1 in contrast to SATB1-AS1 showed a significant prognostic value. Since a significantly concordant expression was observed for SATB1-AS1 and SATB1 in only cancerous, and for PRKCQ-AS1 and PRKCQ in both normal and cancerous colorectal tissues, it can be concluded that common mechanisms may regulate the expression of these sense and antisense genes.

Increased expression of long non-coding RNA CCAT2 predicts poorer prognosis in patients with hepatocellular carcinoma.

Background:Long non-coding RNA colon cancer-associated transcript 2 (CCAT2) is a 1752-bp lncRNA transcribed from m8q24 genomic region. A lot of investigations have confirmed the involvement of CCAT2 in the tumorigenesis of many cancer types. Previous studies found that over-expression of CCAT2 significantly promoted cell migration and proliferation, and inhibited apoptosis of HCC cells. In the present investigation, the clinical value and prognostic significance of CCAT2 were investigated.Methods:The 122 pairs of HCC tissues and adjacent normal liver tissues were acquired between September 2013 and February 2018. The expression levels of CCAT2 in HCC tissues and their corresponding adjacent normal liver tissues were examined by RT-qPCR analysis. Survival was calculated using the Kaplan-Meier method and analyzed using the log-rank test. Independent prognostic indicators were determined in the multivariate analysis using Cox's proportional hazard model.Results:CCAT2 expression levels were significantly increased in HCC tissues compared to that in their normal counterparts (P < .001). CCAT2 expression was significantly correlated with vascular invasion (P = .001), histopathologic grading (P = .001), distant metastasis (P = .002) and TNM stage (P = .018). A Kaplan–Meier survival curve showed that the overall survival rate of HCC patients in high CCAT2 expression group markedly decreased as compared with that of low CCAT2 expression group (P = .016). In addition, COX multivariate analysis showed that high expression of CCAT2 was an independent risk factor for predicting shorter overall survival time in HCC (HR = 2.126, 95%CI:1.273–8.775, P = .021).Conclusions:Taken together, this research revealed that lncRNA CCAT2 may serve as a potential biomarker for predicting overall survival time in HCC.

Assessment of The Lnc-CCAT1/miR-155a Regulatory Network in Acute Myeloid Leukemia

Colon cancer-associated transcript_1 (CCAT1) is a long noncoding RNA that maps to chromosome 8q24.21, it was first discovered to be upregulated in colorectal cancer. Recent studies have observed the CCAT1 overexpression in primary human solid cancers and cell lines as well as in AML, moreover, it repressed monocytic differentiation and promoted cell growth of HL-60 by sequestering tumor suppressive miR-155. However, the prognostic value of CCAT1/miR-155a pathway in acute myeloid Leukemia (AML) has not been investigated on clinical samples. In this study, the expression levels of CCAT1 and miR_155a was measured in 150 AML patients with standard and high-risk factors; CCAT1 and miR_155a were increased by 2.7 and 5.7 folds; respectively in AML compared to healthy controls. Furtherly, upregulation of both biomarkers was significantly associated with high risk AML. Collectively, these results suggest that CCAT1 and miR_155a can be considered as a diagnostic and prognostic biomarker in AML.

LncRNA CCAT1 is a biomarker for the proliferation and drug resistance of esophageal cancer via the miR-143/PLK1/BUBR1 axis.

Recent evidence indicates that long noncoding RNA colon cancer-associated transcript-1 (lncRNA CCAT1) is abundantly expressed in esophageal cancer and is closely related to the occurrence, development, invasion, metastasis, and drug resistance of this disease. However, the role and molecular mechanisms of CCAT1 in the cell proliferation and chemoresistance of esophageal cancer are largely unknown. The correlation between CCAT1 expression and drug resistance to cisplatin (CDDP) in esophageal squamous cell carcinoma (ESCC) cells was analyzed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) and quantitative real-time polymerase chain reaction (qRT-PCR) assays. CCAT1 knockdown and miR-143 overexpression or inhibition were used to verify the effects on proliferation and drug resistance via MTT, western blotting, flow cytometry, and immunofluorescence assays. qRT-PCR and western blotting were applied to detect the potential regulatory relationship among CCAT1, miR-143, PLK1, and BUBR1. A xenograft tumor assay was performed to validate the role of CCAT1 in vivo. The expression of CCAT1 was positively correlated with drug resistance in several ESCC cell lines. CCAT1 knockdown and miR-143 overexpression inhibited cell proliferation and CDDP drug resistance. Moreover, the downstream target of CCAT1 was found to be miR-143, which can regulate the expression of PLK1 and BUBR1. In vivo assays showed that CCAT1 knockdown suppressed tumor growth and enhanced the sensitivity of tumors to CDDP in nude mice. Taken together, we discovered a novel mechanism by which CCAT1 promotes cell proliferation and enhances drug resistance by regulating the miR-143/PLK1/BUBR1 signaling axis both in vitro and in vivo. Our findings further suggest that lncRNA CCAT1 may be a potential therapeutic target for overcoming chemoresistance in esophageal cancer.

LncRNA CCAT1 contributes to the growth and invasion of gastric cancer via targeting miR-219-1.

Gastric cancer (GC) is one of the most malignant tumors that seriously threatenhuman health. Increased reports have indicated that long noncoding RNAs (lncRNAs) areassociated with GC. This study aims to investigate the regulatory role of colon cancer-associated transcript-1 (CCAT1) in GC. The results exhibited the fact that CCAT1 was expressed higher in 57 GC tissue samples than in 57 paired adjacent normal tissue samples. The expression of CCAT1 was also increased in GC cell lines (MKN45, Hs746T, and SGC-7901) compared with the gastric epithelial cell line GES-1. Besidesthis, decreased cell proliferation with increased cell apoptosis wasdetected in SGC-7902 cells transfected with CCAT1 short hairpin RNA (shRNA). At the same time, a lower cell invasion ability was measured in SCG-7901 cells transfected with CCAT1 shRNA.In addition, miR-219-1 was predicted and convinced a direct target of CCAT1. The expression of miR-219-1 was decreased in GC tissues and GC cell lines. Further studies demonstrated that the roles of CCAT1 in cell proliferation, apoptosis, and invasion were inhibited by miR-219-1. Finally, in vivo experiment indicated that tumor growth of GC was suppressed through knockdown of CCAT1. In conclusion, these results suggested that CAT1 promotes the tumorigenesis and progression of GC by negatively regulating miR-219-1.

LncRNA CCAT1 functions as apoptosis inhibitor in podocytes via autophagy inhibition.

Podocyte apoptosis importantly contributes to various kidney diseases. Long noncoding RNAs Colon cancer‐associated transcript‐1 (CCAT‐1) has been demonstrated for a critical role in cell proliferation. In the present study, the relationship between CCAT1 and popdocyte impairment, and the underlying mechanism was investigated. Podocytes were isolated from mice and then treated with tumor necrosis factor‐α to simulate podocyte injury. After developed CCAT1 overexpression or knockdown, cell viabilities were determined with the CCK‐8 assay, apoptosis was examined with Flow cytometry, the autophagy was observed by Western blot. Furthermore, phosphorylated PI3K and Akt expressions were examined. We found that after CCAT1 overexpression, the cell viability was significantly increased, apoptosis was significantly decreased, and autophagy was significantly inhibited, which was indicated by induced P62, LC3B‐I and decreased LC3B‐II. In addition, CCAT1 overexpression induced the levels of phosphorylated PI3K and Akt. With Rap treatment, these effects by CCAT1 were reversed. Furthermore, the results contrary to the effects by CCAT1 overexpression were presented after CCAT1 knockdown, and this was inhibited by 3‐MA. Taken together, our results suggested that CCAT1 induction critically participated in apoptosis inhibition in podocytes through autophagy inhibition via increasing PI3K/Akt signaling. This might act as a promising therapeutic intervention for renal diseases associated with podocyte apoptosis.

Association of lncRNA CCAT2 and CASC8 Gene Polymorphisms with Hepatocellular Carcinoma.

The worldwide incidence of hepatocellular carcinoma (HCC), the major histological type of primary liver cancer, is heterogeneous due to the variable prevalence of etiological factors, indicating a correlation of HCC risk with genetic variations among individuals. Among long non-coding RNAs (lncRNAs) located in the chromosome 8q24 loci and involved in the carcinogenesis are colon cancer associated transcript 2 (CCAT2) and cancer susceptibility candidate 8 (CASC8). In this study, the association of CCAT2 and CASC8 gene polymorphisms with the occurrence of HCC was explored between 397 HCC patients and 1195 controls. We found that carriers of rs6983267 GG in CCAT2 were more susceptible to HCC, with the odds ratio (OR) and adjusted odds ratio (AOR) being 1.532 (95% CI, 1.103–2.129; p = 0.011) and 1.627 (95% CI, 1.120–2.265; p = 0.033), respectively. Moreover, for patients stratified by age (under 65), gender (male only), or status of drinking (habitual drinkers), a protective effect of CASC8 rs3843549 on presenting high Child–Pugh scores, metastatic vascular invasion, or large-size tumors was observed in a dominant model. Collectively, our data reveal association of CCAT2 and CASC8 gene polymorphisms with the occurrence and progression of HCC.

Sinomenine retards LPS-elicited inflammation via down-regulating CCAT1 in HaCaT cells

AimsThe initiation of pressure ulcers is accompanied by inflammation. Sinomenine emerges as a potential anti-inflammation agent. The aim of this study was to corroborate its anti-inflammatory property in skin keratinocyte HaCaT cells. Long non-coding RNA colon cancer associated transcript-1 (CCAT1)-associated mechanisms were also investigated. Main methodsHaCaT cells were stimulated with lipopolysaccharide (LPS) for 6 h after sinomenine pre-administration. Transfection was carried out to induce CCAT1 overexpression or silence it in HaCaT cells. Viability and apoptosis of HaCaT cells were determined by MMT and observed using flow cytometry, respectively. Protein expression was quantified using Western blot or ELISA. CCAT1 was measured by qRT-PCR. Key findingsLPS notably decreased cell viability and exaggerated apoptosis with the cleavage of caspase-3/-9. The secretion of inflammatory factors was promoted. Sinomenine pre-administration maintained cell viability, blocked apoptosis and relieved inflammation with the decrease in cleaved caspase-3/-9 and inflammatory factors. LPS-induced phosphorylation of p65, IκBα and p38MAPK and overexpression of CCAT1 were precluded by sinomenine. CCAT1 overexpression, which per se induced inflammatory lesions, negated the positive effects of sinomenine with the restored phosphorylation of p65, IκBα, and p38MAPK. SignificanceSinomenine played a protective role against LPS-induced inflammation. The anti-inflammatory activity of sinomenine might be mediated by CCAT1 down-regulation.

LncRNA CCAT1 promotes autophagy via regulating ATG7 by sponging miR-181 in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is a significant clinical challenge, and the mechanisms underlying HCC pathogenesis remain incompletely understood. Colon cancer associated transcript 1 (CCAT1), is one novel long noncoding RNA (lncRNA) which is upregulated in HCC. Autophagy is a vital process in HCC progression, and it is unknown whether CCAT1 regulates autophagy in HCC. Immunofluorescence staining and transmission electron microscopy were used to analyze autophagy activity. Luciferase assay was performed to confirm miRNA-181a-5p (miR-181a-5p) bind CCAT1 and ATG7. CCAT1 levels were higher in tissue and cell lines of HCC. In function research, we found that CCAT1 facilitates HCC cell autophagy and cell proliferation. Our results show that, mechanistically, CCAT1 promotes autophagy through functioning as a sponge for miR-181a-5p, and then regulating ATG7 expression. Our findings indicate CCAT1 may play a role in regulating autophagy by sponging miR-181a-5p in HCC.

Long non-coding RNA colon cancer-associated transcript 2 may promote esophageal cancer growth and metastasis by regulating the Wnt signaling pathway.

The aim of this study was to investigate how long non-coding (lnc)RNA colon cancer-associated transcript 2 (CCAT2) regulates the proliferation, invasion and metastasis of esophageal cancer cells via the Wnt signaling pathway. The expression of lncRNA CCAT2 was quantified by reverse transcription-quantitative PCR in four esophageal cancer cell lines (Eca-109, EC9706, KYSE150 and TE-1) and normal human esophageal epithelial cells (HEECs). The effect of silencing CCAT2 (si-CCAT2) and inhibiting Wnt signaling (using the inhibitor FH535) on the proliferation, migration and invasion of Eca-109 cells was measured by MTT, wound-healing and Transwell invasion assays. Flow cytometry was used to evaluate apoptosis in si-CCAT2 Eca-109 cells. The expression of β-catenin and proliferating cell nuclear antigen (PCNA) proteins was detected by immunohistochemistry. The pro-apoptotic protein Bax, cyclin D1 and Wnt target proteins, including c-Myc and adenomatous polyposis coli (APC), were detected by western blotting. LncRNA CCAT2 was highly expressed in the four esophageal cancer cell lines compared with the HEEC cells. The expression of CCAT2 was significantly decreased in si-CCAT2 Eca-109 cells. Treatment with si-CCAT2 and FH535 alone or in combination significantly inhibited the proliferation, migration and invasion of Eca-109 cells. The treatments also promoted apoptosis, upregulated the expression of Bax and APC proteins, and downregulated β-catenin, PCNA, cyclin D1 and c-Myc proteins. In summary, lncRNA CCAT2 is upregulated in esophageal cancer cells and the knockdown of lncRNA CCAT2 inhibits their proliferation, migration and invasion via the Wnt signaling pathway.

Extracellular Vesicles and Their Potential Use in Monitoring Cancer Progression and Therapy: The Contribution of Proteomics.

Extracellular Vesicles (EVs) are small membrane-enclosed particles released by cells and able to vehiculate information between them. The term EVs categorizes many and different vesicles based on their biogenesis and release pathway, such as exosomes (Exo), ectosomes, or shedding microvesicles (SMVs), apoptotic blebs (ABs), and other EVs subsets, generating a heterogeneous group of components able to redistribute their cargo into the entire organism. Moreover EVs are becoming increasingly important in monitoring cancer progression and therapy, since they are able to carry specific disease biomarkers such as Glypican-1, colon cancer-associated transcript 2, CD63, CD24, and many others. The importance of their biological role together with their heterogeneity prompted researchers to adopt and standardize purification methods able to isolate EVs for characterizing their cargo. In this way, mass spectrometry (MS)-based proteomics approaches are emerging as promising tool for the identification and quantification of EVs protein cargoes, but this technique resulted to be deeply influenced by the low quality of the isolation techniques. This review presents the state-of-the-art of EVs isolation, purification, and characterization for omics studies, with a particular focus to their potential use in monitoring cancer progression and therapy.

LncRNA CCAT1 promotes bladder cancer cell proliferation, migration and invasion.

ABSTRACTObjective:To study the expression patterns of long noncoding RNA (lncRNA) colon cancer-associated transcript 1 (CCAT1) and the changes in cell proliferation, apoptosis, migration and invasion induced by silencing CCAT1 in bladder cancer cells.Materials and Methods:The expression levels of CCAT1 were determined using realtime quantitative polymerase chain reaction in cancerous tissues and paired normal tissues from 34 patients with bladder cancer. The relationship between clinical characteristics and CCAT1 expression was analyzed. And then we conducted cell experiments. Bladder urothelial carcinoma cell lines T24 and 5637 cells were transfected with CCAT1 small interfering RNA (siRNA) or scramble siRNA. Cell proliferation and apoptosis changes were determined using a Cell Counting Kit-8 (CCK-8) assay and a flow cytometry assay. Migration and invasion changes were measured using a wound healing assay and a trans-well assay. microRNAs (miRNAs) were predicted by Starbase 2.0, and their differential expression levels were studied.Results:CCAT1 was significantly upregulated in bladder cancer (P < 0.05). CCAT1 upregulation was positively related to tumor stage (P = 0.004), tumor grade (P = 0.001) and tumor size (P = 0.042). Cell proliferation, migration and invasion were promoted by abnormally expressed CCAT1. miRNAs miR-181b-5p, miR-152-3p, miR-24-3p, miR-148a-3p and miR-490-3p were potentially related to the aforementioned functions of CCAT1.Conclusion:CCAT1 plays an oncogenic role in urothelial carcinoma of the bladder. In addition, CCAT1 may be a potential therapeutic target in this cancer.