Identification of CD147-positive extracellular vesicles as novel non-invasive biomarkers for the diagnosis and prognosis of colorectal cancer.

BACKGROUND: The mortality rate of colorectal cancer (CRC) can be decreased with effective screening and early diagnosis. Exosomes are released from cancer cells into the bloodstream, and circulating exosomes may serve as novel biomarkers. This study aimed to identify a sensitive and rapid method of exosome collection and measurement using specific antibodies. METHODS: ExoCounter, a high-sensitive exosome-counting system, allows the identification of exosomes without enrichment or purification, based on the identification of the transmembrane protein-CD147-on serum exosomes that are associated with CRC. RESULTS: Receiver operating characteristic curves between healthy donors and CRC patients were described and assessed by CD147-specific exosomes (exo-CD147), CEA, and CA19-9. And area under curves for exo-CD147, CEA, and CA19-9 were 0.827 (95%CI: 0.764-0.891), 0.630 (95%CI: 0.536-0.724), and 0.659 (95%CI: 0.559-0.759), respectively. Drawing a clinical decision curve of exo-CD147 for the diagnosis of CRC metastases showed that when the threshold probability of exo-CD147 was between 20% and 92%, the net clinical utilization rate was higher than for all patients with or without metastases. A nomogram was constructed using multivariate COX regression analysis to select significant variables such as the high CD147 group (>34 × 105 particles). Calibration curves for 1-, 3-, and 5-year survival rates of CRC patients showed that the actual 1-, 3-, and 5-year survival rates were in excellent agreement with the survival rates predicted by the nomogram. CONCLUSIONS: The increased CD147 expression in exosomes could serve as a diagnostic and prognostic biomarker for CRC.

Erratum: Myeloid cell-derived LL-37 promotes lung cancer growth by activating Wnt/ß-catenin signaling: Erratum.

[This corrects the article DOI: 10.7150/thno.30726.].

Immune Infiltration of Ulcerative Colitis and Detection of the m6A Subtype.

Ulcerative colitis (UC) is an inflammatory bowel disease characterized by persistent colon inflammation. N6-methyladenosine (m6A) methylation is one of the most prevalent RNA modifications with key roles in both normal and illness, but m6A methylation in ulcerative colitis is unknown. This research investigated m6A methylation in UC. We examined the expression of known m6A RNA methylation regulators in UC using the Gene Expression Omnibus database (GEO database). First, we used m6A regulators to examine m6A change in UC samples. These two patient groups were created by clustering three m6A gene expression datasets. These genes were then utilized to build an m6A gene network using WGCNA and PPI. These networks were built using differentially expressed genes. The 12 m6A regulators were found to be dispersed throughout the chromosome. The study's data were then connected, revealing positive or negative relationships between genes or signaling pathways. Then, PCA of the 12 m6A-regulated genes indicated that the two patient groups could be discriminated in both PC1 and PC2 dimensions. The ssGSEA algorithm found that immune invading cells could be easily distinguished across diverse patient groups. Both groups had varied levels of popular cytokines. The differential gene analysis of the two samples yielded 517 genes like FTO and RFX7. It found 9 hub genes among 121 genes in the blue module, compared their expression in two groups of samples, and found that the differences in expression of these 9 genes were highly significant. The identification of 9 possible m6A methylation-dependent gene regulatory networks suggests that m6A methylation is involved in UC pathogenesis. Nine candidate genes have been identified as possible markers for assessing UC severity and developing innovative UC targeted therapeutic approaches.

Immune Infiltration and N(6)-Methyladenosine ncRNA Isoform Detection in Acute Lung Injury.

Acute lung injury (ALI) is a severe form of sepsis that is associated with a high rate of morbidity and death in critically ill individuals. The emergence of ALI is the result of several factors at work. Case mortality rates might range from 40% to 70%. Researchers have discovered that epigenetic alterations are important in the pathophysiology of ALI and that using epigenetic inhibitors may help reduce symptoms. In embryonic development, circadian rhythm, the cell cycle, and cancer, methylation of m6A seems to be relevant all along the way. According to recent research, posttranscriptional methylation is a key player in the development of alveolar lymphoma. In this study, we clustered ALI based on m6A-related factors, analyzed different classes of immune cell enrichment and inflammatory cytokine expression, screened clustered differential genes for ALI to construct coexpression networks, screened key ALI genes potentially regulated by m6A modifications, and then typed the disease based on key genes to compare the consistency of different clustering results. Our findings have revealed a hitherto undiscovered prognostic sign and a therapeutic target for ALI therapy in m6A and immune invading cells, respectively.

NCOA4: An Immunomodulation-Related Prognostic Biomarker in Colon Adenocarcinoma and Pan-Cancer.

Treatment of cancer in humans requires a thorough understanding of the multiple pathways by which it develops. Recent studies suggest that nuclear receptor coactivator 4 (NCOA4) may be a predictive biomarker for renal cancer. In the present work, TCGA, GEPIA, and several bioinformatics approaches were used to analyze the NCOA4 expression patterns, prognostic relevance, and association between NCOA4 and clinicopathological features and immune cell infiltration. We investigated NCOA4 expression in malignancies. Low NCOA4 expression was associated with poor overall survival in individuals with malignancies such as cholangiocarcinoma, colon adenocarcinoma, and clear cell renal carcinoma. We also analyzed NCOA4 DNA methylation in normal and primary tumor tissues and investigated possible functional pathways underlying NCOA4-mediated oncogenesis. In conclusion, downregulation of NCOA4 is associated with poor prognosis, and NCOA4 may be a predictive biomarker for COAD.

Tumor-Originated Exosomal hsa-miR-3937 as a Minimally Invasive Early Biomarker for Liquid Biopsy of Colorectal Cancer.

Background: Exosomal microRNAs (miRNAs) have been linked to the genesis and progression of certain cancers. The role and regulation mechanism of cancer-derived exosomal miRNAs in CRC, however, remain unknown. Methods: To address this, we first used miRNA sequencing to describe the miRNA profiles of circulating exosomes in order to identify miRNAs that were differently expressed between patients with CRC and healthy controls. Transmission electron microscopy, nanoparticle tracking analysis (NTA), and western blot were used to analyze exosomes generated from CRC cells. CCK-8, wound healing, and Transwell tests were used to see whether exosomes affected CRC cell proliferation, metastasis, and apoptosis, respectively. We chose and identified hsa-miR-3937, which was abundant in tumor-generated exosomes, based on earlier RNA sequencing data of exosomes obtained and extracted from seven matched specimens of tumor tissues and surrounding normal tissues of CRC patients. Results: The role of hsa-miR-3937 in CRC cells was found, and silencing of hsa-miR-3937 decreased CRC cell invasion and migration in a Transwell experiment. Furthermore, we discovered that there was no link between hsa-miR-3937 expression and CRC cell apoptosis. Initially, it was discovered that BCL2L12 was the target gene of hsa-miR-3937, and the TCGA database highlighted the potential therapeutic relevance of BCL2L12. Furthermore, to identify hsa-miR-3937 as a biomarker of CRC, we used peripheral blood samples rather than patient tissues and extracted exosomes from plasma samples. To assess the expression levels and predictive usefulness of plasma exosomal hsa-miR-3937 in CRC, we performed RT-qPCR to identify hsa-miR-3937 levels in all samples. We also gathered clinicopathological information in order to look for links between aberrant hsa-miR-3937 expression and clinicopathological characteristics. The pathologic stage of CRC patients was linked to hsa-miR-3937 expression levels, and the same was true for the T stage. ROC curve study revealed that hsa-miR-3937 outperforms CEA and CA199. The combination of hsa-miR-3937, CEA, and CA199 exhibited the highest sensitivity for CRC diagnosis. Conclusions: Our findings show that the tumor-originated exosomal hsa-miR-3937 is a potential and effective liquid biopsy marker for colorectal cancer detection and therapy.

Urinary Exosomal Long Noncoding RNA TERC as a Noninvasive Diagnostic and Prognostic Biomarker for Bladder Urothelial Carcinoma.

PURPOSE: Bladder cancer is one of the most common urological malignancies worldwide, and approximately 90% of bladder cancer cases are histologically typed as bladder urothelial carcinoma (BLCA). Exosomes are 30 to 200 nm extracellular vesicles that transport microRNAs, long noncoding RNAs (lncRNAs), mRNAs, circular RNAs, and proteins across tissues and through circulation. Urinary exosomes may contain genetic information from tumor cells. Herein, we explored the clinical significance of urinary exosomal lncRNA telomerase RNA component (TERC) levels to provide an urgently needed diagnostic and prognostic biomarker for BLCA. MATERIALS AND METHODS: In this study, we used RNA-sequencing of samples from four BLCA patients and three healthy controls to identify that TERC was differentially expressed in urinary exosomes. We then used quantitative PCR in different types of clinical samples to validate the biomarker and analyzed results using receiver operating characteristic curves. RESULTS: We found that TERC was significantly upregulated in urinary exosomes from BLCA patients compared with those from healthy controls (P < 0.0001). Urinary exosomal TERC showed higher sensitivity (78.65%) and accuracy (77.78%) than existing indicators including nuclear matrix protein-22 and urine cytometry. Using the cut-off value 4.302, the area under the curve for urinary exosomal TERC was 0.836 (95% confidence interval: 0.768-0.891, P < 0.0001). Furthermore, this noninvasive assay could distinguish low-grade and high-grade tumors (P = 0.0153). CONCLUSIONS: TERC is enriched in urinary exosomes from BLCA patients. Urinary exosomal TERC could become a diagnostic and prognostic biomarker for BLCA that allows clinicians to realize noninvasive detection of BLCA.

IGF2BP2 promotes the progression of colorectal cancer through a YAP-dependent mechanism.

To explore the effect of insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) on colorectal cancer (CRC) by recognizing the m6A modification of YAP mRNA thus activating ErbB2 expression. High expressions of IGF2BP2, YAP, and ErbB2 promoted the proliferation, migration and invasion of CRC cells and reduced their apoptosis. IGF2BP2 recognized the m6A on YAP mRNA and promoted the translation of mRNA. YAP regulated ErbB2 expression by promoting TEAD4 enrichment in ErbB2 promoter region. Therefore, IGF2BP2 promoted the expression of ErbB2 to enhance the proliferation, invasion and migration of CRC cells, to repress cell apoptosis, and to promote solid tumor formation in nude mice. IGF2BP2 activates the expression of ErbB2 by recognizing the m6A of YAP, thus affecting the cell cycle of CRC, inhibiting cell apoptosis, and promoting proliferation.

Correction to: Long non-coding RNA HOTTIP enhances IL-6 expression to potentiate immune escape of ovarian cancer cells by upregulating the expression of PD-L1 in neutrophils.

An amendment to this paper has been published and can be accessed via the original article.

A nomogram from the SEER database for predicting the prognosis of patients with non-small cell lung cancer.

OBJECTIVE: The purpose of this study was to establish and validate a nomogram to predict the prognosis in patients with non-small cell lung cancer (NSCLC) from multiple perspectives. RESULTS: A total of 98,640 eligible patients were randomly divided into a training set (n = 69,048) and a validation set (n = 29,592). The baseline characteristics of the two sets were similar. We used clinical data from patients in the training set for univariate and multivariate Cox regression analyses. Twelve independent risk factors were incorporated for constructed a prognostic nomogram. And the nomogram with a concordance index of 0.777 (95 % CI, 0.775 to 0.779) for overall survival. The calibration curve results showed that the actual survival rate was consistent with the predicted survival rate. The area under curve of the receiver operating characteristic curves demonstrated that the nomogram has a high prediction of the overall survival rate in patients with NSCLC. CONCLUSION: We have developed a nomogram with high prediction accuracy and discrimination ability, which can help clinicians making personalized survival predictions for NSCLC patients.

Novel evidence for retinoic acid-induced G (Rig-G) as a tumor suppressor by activating p53 signaling pathway in lung cancer.

Lung cancer is one of most common malignancies worldwide. We have previously identified retinoic acid-induced gene G (Rig-G) as a tumor suppressor in not only acute promyelocytic leukemia, but also in other solid tumors. However, the clinical significance of Rig-G and the underlying mechanism(s) for its biological function in lung cancer remain largely unexplored. Herein, we first compared the expression of Rig-G between lung cancer (n = 138) and normal tissues (n = 23), from public-available data sets and our patient cohort. We further analyzed the correlation of Rig-G expression with key clinico-pathological features and survival outcomes in a multi-site clinical cohort of 300 lung cancer patients. Functional studies for Rig-G were performed in cell lines, and an animal model to support clinical findings. We found that Rig-G was frequently downregulated in lung cancer tissues and cell lines, and correlated with poor prognosis in lung cancer patients. Overexpression of Rig-G led to significantly reduced cell growth and suppressed migration in A549 and NCI-H1944 cells, accompanied by reduced epithelial-mesenchymal transition. Likewise, restoration of Rig-G in Lewis lung carcinoma cells permitted development of fewer cancer metastases versus controls in an animal model. Gene expression profiling results identified p53 pathway as a key downstream target of Rig-G, and p53 inhibition by pifithrin-α caused abrogation of tumor-suppressive effects of Rig-G in lung cancer. In conclusion, we, for the first time, have identified Rig-G as a novel and important tumor suppressor, which may serve as a potential therapeutic target for restoring p53 expression in lung cancer patients.

Exosomal circPACRGL promotes progression of colorectal cancer via the miR-142-3p/miR-506-3p- TGF-ß1 axis.

BACKGROUND: Colorectal cancer (CRC) is the leading cause of cancer-related death worldwide. Exosome shave emerged as crucial regulators of intercellular communication and that abundant Circular RNAs (circRNAs) are enriched within exosomes. CircRNAs are novel members of noncoding RNAs regulating cancer proliferation and progression. However, the function and regulatory mechanism of cancer-derived exosomal circRNAs in CRC remains unclear. METHODS: CRC cells-derived exosomes were characterized using transmission electron microscopy, nanoparticle tracking analysis (NTA) and western blot. CCK-8, wound healing and transwell assays, and flow cytometry assays were conducted to assess whether exosomes would affect the proliferation, metastasis, and apoptosis of CRC cells, respectively. Moreover, we performed the RNA sequencing and RT-qPCR to identify circRNAs in exosome-stimulated CRC cells. Fluorescence in situ hybridization (FISH) assay was used to detect the cellular distribution of circPACRGL. Bioinformatic analyses (StarBase 2.0) were used to pool the miRNA targets of circPACRGL. Luciferase assays were performed to verify the direct interaction. Finally, flow cytometry was used to detect the differentiation of N1-N2 neutrophils. RESULTS: Our study identified a novel CRC-derived exosomal circRNA, circPACRGL. We found circPACRGL was significantly upregulated in CRC cells after tumor-derived exosomes addition. Moreover, circPACRGL serves as a sponge for miR-142-3p/miR-506-3p to facilitate the transforming growth factor-ß1 (TGF-ß1) expression. As a result, circPACRGL promoted CRC cell proliferation, migration and invasion, as well as differentiation of N1 to N2 neutrophils via miR-142-3p/miR-506-3p-TGF-ß1 axis. CONCLUSION: Our study, the first to reveal that cancer-derived exosomal circPACRGL plays an oncogenic role in CRC proliferation and metastasis, providing mechanistic insights into the roles of circRNAs in CRC progression and a valuable marker for CRC treatment.

Exosomal miR-183-5p promotes angiogenesis in colorectal cancer by regulation of FOXO1.

Exosomes play important roles in proliferation and microenvironment modulation of many types of cancers, including colorectal cancer (CRC). However, the inhibitory effect of CRC cells-derived exosomes in angiogenesis has not been fully discussed. In this study, the roles of microRNA-183-5p (miR-183-5p) in abundant in exosomes secreted from the CRC cells were investigated. Initially, microarray analysis was employed to determine the differentially expressed miRNAs. Exosomes isolated from CRC cells were co-cultured with HMEC-1 cells to explore the role of exosomes in angiogenesis. Further, the effects of CRC cell-derived exosomal miR-183-5p on proliferation, invasion and tube formation abilities of HMEC-1 cells were assessed. The preventative effect of exosomal miR-183-5p in vivo was measured in nude mice. Initially, it was found that FOXO1 was downregulated while miR-183-5p was upregulated in CRC. Additionally, the inhibition of miR-183-5p was suggested to suppress proliferation, invasion and tube formation abilities of HMEC-1 cells through upregulating FOXO1. Then, in vitro assays demonstrated that CRC cell-derived exosomes overexpressing miR-183-5p contributed to an enhanced proliferation, invasion and tube formation abilities of HMEC-1 cells. Furthermore, in vivo experiments confirmed the tumor-promotive effects of CRC cell-derived exosomal miR-183-5p. Collectively, our study demonstrates that the CRC cell-derived exosomes overexpressing miR-183-5p aggravates CRC through the regulation of FOXO1. Exosomes overexpressing miR-183-5p might be a potential treatment biomarker for CRC.

Long non-coding RNA CCAT1 promotes colorectal cancer progression by regulating miR-181a-5p expression.

The vital roles of long noncoding RNAs (lncRNAs) have been implicated in growing number of studies in tumor development. LncRNA CCAT1 has been recognized as associated with tumor development, yet its relation with colorectal cancer (CRC) remains elusive. Our study aimed at elucidating the function and mechanisms of long non-coding RNA CCAT1 in CRC. From a lncRNA profile dataset of 38 pairs of matched tumor-control colon tissues from colorectal patients housed in The Cancer Genome Atlas (TCGA), we detected 10 upregulated and 10 down-regulated lncRNAs in CRC. Fifty cases of CRC patients were enrolled to analyze the correlation between the expression of CCAT1 and clinical pathology. The inverse correlation of expression and target relationship between CCAT1 and miR-181a-5p were verified using qRT-PCR and dual-luciferase reporter gene assay. Cell viability, colony formation ability, aggression and apoptosis were determined by MTT assay, colony formation assay, Transwell and wound healing assays and flow cytometry analysis. Furthermore, Xenograft model was used to show that knockdown of CCAT1 inhibits tumor growth in vivo. The expression of lncRNA CCAT1 was significantly upregulated in CRC tissues. The CCAT1 expression was positively associated with cancer stage (American Joint Committee on Cancer stage, P<0.05). CCAT1 promoted cell proliferation, growth and mobility by targeting miR-181a-5p and the silence of CCAT1 increased the cell apoptosis. Same effect was observed in an in vivo xenograft model, which the tumor size and pro-tumor proteins were significantly diminished by knocking down of CCAT1.

Exosomal KRAS mutation promotes the formation of tumor-associated neutrophil extracellular traps and causes deterioration of colorectal cancer by inducing IL-8 expression.

BACKGROUND: Colorectal cancer (CRC) remains one of the leading causes of cancer-related death. The current study aimed to elucidate the mechanism by which exosomes carrying KRAS mutant contribute to neutrophil recruitment as well as the formation of the neutrophil extracellular trap (NET) in CRC. METHODS: APC-WT and APC-KRASG12D mouse models were initially developed. Peripheral blood, spleen, bone marrow (BM) and mesenteric lymph nodes (mLN) were isolated to detect neutrophil content. Then, APC-WT and APC-KRASG12D mice were injected with exosomes isolated from APC-WT and APC-KRASG12D mice. The ratio of neutrophils, NETs formation and IL-8 protein content were subsequently quantified in colon tissues. DKs-8 (wild type) and DKO-1 (KRAS mutant) cells were employed for in vitro experimentation. Then, DKs-8 cells were cultured with exosome-treated PMA stimulated neutrophil-forming NETs culture medium, with cell viability, invasion, migration, and adhesion evaluated. RESULTS: Compared with APC-WT mice, the numbers of polyps and neutrophils in the peripheral blood, spleen and mLNs were increased in APC-KRASG12D mice, accompanied with increased NET formation, IL-8 expression and exosomes. Meanwhile, IL-8 upregulation, neutrophil recruitment and NET formation were observed in the mice injected with exosomes derived from APC-KRASG12D. The in vitro investigation results revealed that more NETs were formed in the presence of DKO-1-Exos, which were inhibited by DNAse. In addition, DKs-8- and DKO-1 cells-derived exosomes could adhere to NETs under static conditions in vitro. Exosomal KRAS mutants were noted to exert stimulatory effects on the IL-8 production and NET formation to promote the growth of CRC cells. CONCLUSION: The results provide evidence suggesting that exosomes may transfer mutant KRAS to recipient cells and trigger increases in IL-8 production, neutrophil recruitment and formation of NETs, eventually leading to the deterioration of CRC.

Long non-coding RNA HOTTIP enhances IL-6 expression to potentiate immune escape of ovarian cancer cells by upregulating the expression of PD-L1 in neutrophils.

BACKGROUND: Long non-coding RNA (lncRNA) HOXA transcript at the distal tip (HOTTIP), has been demonstrated to be a vital biomarker when evaluating the prognosis of multiple cancers. Nevertheless, the potential function of HOTTIP in ovarian cancer (OC), a prevalent cancer among women worldwide, remains elusive. Hence, the current study aimed to elucidate the functional relevance of HOTTIP in the development of OC. METHODS: Positive expression of PD-L1 and IL-6 was determined using immunohistochemical staining in the collected OC and normal tissues. The correlation of IL-6 and PD-L1 was analyzed using flow cytometry, Western blot analysis as well as Pearson's correlation coefficient. The interaction among HOTTIP, c-jun and IL-6 was investigated with the use of RIP, ChIP and dual luciferase reporter gene assays. Finally, the effects of HOTTIP on T cell proliferation and infiltration were identified through gain- and loss-of-function studies in vitro and in vivo. RESULTS: HOTTIP, IL-6 and PD-L1 were all highly expressed in OC tissues. A positive correlation was observed between IL-6 and PD-L1 and that between HOTTIP and IL-6 in OC tissues. HOTTIP was noted to promote the expression of IL-6 by binding to c-jun, which resulted in a promoted PD-L1 expression in neutrophils and immune escape while inhibiting T cell proliferation as well as tumor immunotherapy. CONCLUSION: Taken together, our study unveiled that HOTTIP could promote the secretion of IL-6, and consequently up-regulate the expression of PD-L1 in neutrophils, thus inhibiting the activity of T cells and ultimately accelerating immune escape of OC cells. Our study provides a potential therapeutic strategy by targeting HOTTIP in OC.

Myeloid cell-derived LL-37 promotes lung cancer growth by activating Wnt/ß-catenin signaling.

Rationale: Antimicrobial peptides, such as cathelicidin LL-37/hCAP-18, are important effectors of the innate immune system with direct antibacterial activity. In addition, LL-37 is involved in the regulation of tumor cell growth. However, the molecular mechanisms underlying the functions of LL-37 in promoting lung cancer are not fully understood. Methods: The expression of LL-37 in the tissues and sera of patients with non-small cell lung cancer was determined through immunohistological, immunofluorescence analysis, and enzyme-linked immunosorbent assay. The animal model of wild-type and Cramp knockout mice was employed to evaluate the tumorigenic effect of LL-37 in non-small cell lung cancer. The mechanism of LL-37 involving in the promotion of lung tumor growth was evaluated via microarray analyses, recombinant protein treatment approaches in vitro, tumor immunohistochemical assays, and intervention studies in vivo. Results: LL-37 produced by myeloid cells was frequently upregulated in primary human lung cancer tissues. Moreover, its expression level correlated with poor clinical outcome. LL-37 activated Wnt/ß-catenin signaling by inducing the phosphorylation of protein kinase B and subsequent phosphorylation of glycogen synthase kinase 3ß mediated by the toll-like receptor-4 expressed in lung tumor cells. LL-37 treatment of tumor cells also decreased the levels of Axin2. In contrast, it elevated those of an RNA-binding protein (tristetraprolin), which may be involved in the mechanism through which LL-37 induces activation of Wnt/ß-catenin. Conclusion: LL-37 may be a critical molecular link between tumor-supportive immune cells and tumors, facilitating the progression of lung cancer.

Knockdown of long noncoding RNA PVT1 suppresses cell proliferation and invasion of colorectal cancer via upregulation of microRNA-214-3p.

Long noncoding RNAs (lncRNAs) have been reported to be involved in the occurrence and tumorigenesis of numerous malignant cancers. Microarray expression profiles were used to screen colorectal cancer (CRC)-related differentially expressed genes and lncRNAs, which revealed that insulin receptor substrate 1 (IRS1) and lncRNA plasmacytoma variant translocation 1 (PVT1) were highly expressed in CRC. This study aimed to investigate the regulatory role of lncRNA PVT1 in CRC. Subcellular localization detected by fluorescence in situ hybridization identified that lncRNA PVT1 was primarily located in the cytoplasm. The interaction between lncRNA PVT1 and microRNA-214-3p (miR-214-3p) and IRS1 was predicted using the RNA22 website. Next the dual luciferase reporter gene assay, RNA pull-down, and RNA immunoprecipitation assays verified lncRNA PVT1 to be a competitive endogenous RNA (ceRNA) against miR-214-3p, and IRS1 was found to be a target of miR-214-3p. The expression pattern of lncRNA PVT1, miR-214-3p, IRS1, phosphoinositide 3-kinase (PI3K), and Akt was characterized in response to lncRNA PVT1 silencing or miR-214-3p upregulation. Meanwhile, their regulatory effects on cell proliferation, invasion, and apoptosis were detected in CRC cells. With increased levels of miR-214-3p and decreased levels of lncRNA PVT1 in CRC cells, the expression of phosphatidylinositol 3-kinase, putative (PI3K) and Akt was reduced, and consequently, the cell apoptosis was stimulated and cell proliferation and invasion were suppressed. All in all, lncRNA PVT1 competitively binds to miR-214-3p to upregulate the expression of IRS1 thus activating the PI3K/Akt signaling pathway, thus accelerating CRC progression. This study suggests that lncRNA PVT1 might be a potential target of therapeutic strategies for CRC treatment.NEW & NOTEWORTHY This study mainly suggests that long noncoding (lnc)RNA plasmacytoma variant translocation 1 (PVT1) is a downregulated lncRNA in colorectal cancer (CRC), accelerating CRC progression. Strikingly, lncRNA PVT1 acts as a competitive endogenous RNA against microRNA (miR)-214-3p, whereas miR-214-3p targets insulin receptor substrate 1, which draws a comprehensive picture of the potential molecular mechanisms of lncRNA PVT1 in CRC.

Bronchoalveolar Lavage Fluid-Derived Exosomes: A Novel Role Contributing to Lung Cancer Growth.

Exosomes are nanovesicles produced by a number of different cell types and regarded as important mediators of cell-to-cell communication. Although bronchoalveolar lavage fluid (BALF) has been shown to be involved in the development of tumors, its role in lung cancer (LC) remains unclear. In this article, we systemically studied BALF-derived exosomes in LC. C57BL/6 mice were injected with Lewis lung carcinoma cells and exposed to non-typeable Haemophilus influenza (NTHi) lysate. The analysis showed that the growth of lung tumors in these mice was significantly enhanced compared with the control cohort (only exposure to air). Characterization of the exosomes derived from mouse BALF demonstrated elevated levels of tumor necrosis factor alpha and interleukin-6 in mice exposed to NTHi lysates. Furthermore, abnormal BALF-derived exosomes facilitated the development of LC in vitro and in vivo. The internalization of the BALF-derived exosomes contributed to the development of LC tumors. Collectively, our data demonstrated that exosomes in BALF are a key factor involved in the growth and progression of lung cancer.