Exosomal circLPAR1 functions in colorectal cancer diagnosis and tumorigenesis through suppressing BRD4 via METTL3-eIF3h interaction.

BACKGROUND: Exosomes have emerged as vital biomarkers of multiple cancers and contain abundant circular RNAs (circRNAs). However, the potential for exosomal circRNAs to be used in diagnostics and their molecular mechanism of action in colorectal cancer (CRC) remain unclear. METHODS: CRC-specific exosomal circRNAs were identified by RNA sequencing, exoRBase database and a tissue microarray. The diagnostic performance of plasma exosomal circRNAs was evaluated among cancer-free controls, precancer individuals, CRC patients, and patients with other types of cancer. The corresponding biological functions were mainly assessed using circRNA pull-down, proteomic analysis, and RNA immunoprecipitation assay underlying cellular and mouse models. RESULTS: CircLPAR1 was encapsulated in exosomes with high stability and detectability, and its expression in plasma exosomes was remarkably decreased during CRC development but recovered after surgery. Exosomal circLPAR1 showed cancer specificity in CRC diagnosis and increased the diagnostic performance to an area under the receiver operating characteristic curve of 0.875, as determined by analysing its performance in combination with common clinical biomarkers CEA and CA19-9. Additionally, circLPAR1 was downregulated in CRC tissues and was associated with overall survival. Mechanistically, exosomal circLPAR1 was internalized by CRC cells, and it suppressed tumor growth, likely because exosomal circLPAR1 directly bound with eIF3h specifically suppressed the METTL3-eIF3h interaction, decreasing the translation of oncogene BRD4. CONCLUSIONS: This comprehensive study highlights plasma exosomal circLPAR1 as a promising predictor in CRC diagnosis and describes its biological regulation of colorectal tumorigenesis. This study provides a new perspective on early diagnosis in the clinic and pathogenesis in disease development.

Afatinib combined with anlotinib in the treatment of lung adenocarcinoma patient with novel HER2 mutation: a case report and review of the literature.

BACKGROUND: HER2 is a member of the ERBB family of receptor tyrosine kinases, and HER2 mutations occur in 1-4% of non-small cell lung cancer (NSCLC) as an oncogenic driver mutation. We found a rare mutation of HER2 p.Asp769Tyr in NSCLC. CASE PRESENTATION: We presented a case of a 68-year-old nonsmoking male patient with brain metastasis from lung adenocarcinoma harboring a rare mutation of HER2 p.Asp769Tyr. After multiple lines of treatment, he obtained a durable response (10 months) to afatinib and anlotinib. CONCLUSION: We reported for the first time that afatinib and anlotinib have successfully treated lung adenocarcinoma with HER2 p.Asp769Tyr mutation. This finding can provide an insight into the optimal treatment of lung adenocarcinoma patients with novel mutations. Additionally, we summarized the efficacy of targeted therapy for HER2 mutant lung cancer in this article.

Coexistence of a novel NBEA-ALK, EML4-ALK double-fusion in a lung adenocarcinoma patient and response to alectinib: A case report.

OBJECTIVES: The echinoderm microtubule-associated protein-like 4 gene (EML4) and anaplastic lymphoma kinase gene (ALK) fusion is the most common ALK rearrangements in non-small cell lung cancer (NSCLC). Herein, we firstly report that coexistence of a novel Neurobeachin (NBEA)-ALK, EML4-ALK double-fusion is sensitive to alectinib. MATERIALS AND METHODS: Hematoxylin-eosin staining (HE), fluorescent in situ hybridization (FISH), and next-generation sequencing (NGS) was performed on the biopsy sample. RESULTS: The patient responded to alectinib as a second-line treatment and achieved stable disease for 11 months, without significant symptoms of toxicity. Significantly, the liquid biopsy also validated clinical benefit, with the disappearance of NBEA-ALK and EML4-ALK fusion variants. We also provided a comprehensive review of all 50 ALK fusion genes in NSCLC. CONCLUSION: This is the first report on one patient with a novel NBEA-ALK, EML4-ALK double-ALK fusion beneficial from alectinib. Alectinib may be a viable therapeutic option for NSCLC patients with double-ALK fusion, and liquid biopsy could dynamically monitor clinical curative effect.

A methylation-based prognostic model predicts survival in patients with colorectal cancer.

BACKGROUND: To construct a model that could effectively predict the prognosis of colorectal cancer (CRC) by searching for methylated-differentially expressed genes (MDEGs). METHODS: We identified MDEGs through four databases from Gene Expression Omnibus (GEO) and annotated their functions via bioinformatics analysis. Subsequently, after adjusting for gender, age, and grading, multivariate Cox hazard analysis was utilized to select MDEGs interrelated with the prognosis of CRC, and LASSO analysis was utilized to fit the prediction model in the training set. Furthermore, another independent dataset was harnessed to verify the effectiveness of the model in predicting prognosis. RESULTS: In total, 252 hypomethylated and up-regulated genes and 132 hypermethylated and down-regulated genes were identified, 27 of which were correlated with the prognosis of CRC, and a 10-gene prognostic model was established after LASSO analysis. The overall survival rate could be effectively grouped into different risks by the median score of this model in the training set [risk ratio (HR) =2.27, confidence interval (95% CI), 1.69-3.13, P=8.15×10-8], and the validity of its effect in predicting prognosis in CRC was verified in the validation dataset (HR =1.75, 95% CI, 1.15-2.70, P=9.32×10-3). CONCLUSIONS: Our model could effectively predict the overall survival rate of patients with CRC and provides potential application guidelines for its clinically personalized treatment.

Circular RNAs in body fluids as cancer biomarkers: the new frontier of liquid biopsies.

Cancer is a leading cause of death worldwide, particularly because of its high mortality rate in patients who are diagnosed at late stages. Conventional biomarkers originating from blood are widely used for cancer diagnosis, but their low sensitivity and specificity limit their widespread application in cancer screening among the general population. Currently, emerging studies are exploiting novel, highly-accurate biomarkers in human body fluids that are obtainable through minimally invasive techniques, which is defined as liquid biopsy. Circular RNAs (circRNAs) are a newly discovered class of noncoding RNAs generated mainly by pre-mRNA splicing. Following the rapid development of high-throughput transcriptome analysis techniques, numerous circRNAs have been recognized to exist stably and at high levels in body fluids, including plasma, serum, exosomes, and urine. CircRNA expression patterns exhibit distinctly differences between patients with cancer and healthy controls, suggesting that circRNAs in body fluids potentially represent novel biomarkers for monitoring cancer development and progression. In this study, we summarized the expression of circRNAs in body fluids in a pan-cancer dataset and characterized their clinical applications in liquid biopsy for cancer diagnosis and prognosis. In addition, a user-friendly web interface was developed to visualize each circRNA in fluids ( https://mulongdu.shinyapps.io/circrnas_in_fluids/ ).

The association between plasma fibrinogen levels and lung cancer: a meta-analysis.

BACKGROUND: Published studies have presented an inconsistent association between plasma fibrinogen level and poor prognosis or clinicopathological characteristics in lung cancer. METHODS: In the absence of significant quality difference, combined hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) were calculated according to overall survival (OS), progression-free survival (PFS) and disease-free survival (DFS). Risk ratio (RR), odds ratio (OR) and standardized mean difference (SMD) with CIs were pooled to appraise the effect of plasma fibrinogen on clinicopathological characteristics. Furthermore, we directly combined the P values to estimate the association of plasma fibrinogen and tumor size. We adjusted the publication bias using trim-and fill method. RESULTS: Twenty studies with 6,494 patients were contained in meta-analysis. The pooled data indicated that elevated fibrinogen level associated with poor prognosis in lung cancer. Typically, the pooled HRs were 1.44 (95% CI, 1.34-1.55), 1.49 (95% CI, 1.24-1.80) and 1.69 (95% CI, 1.31-2.17) for OS, PFS and DFS of lung cancer, respectively. In addition, the combined ORs were 1.50 (95% CI, 1.23-1.84) and 2.01 (95% CI, 1.66-2.44) for lymph node metastasis and III-IV stage; and the combined RR was 2.15 (95% CI, 1.11-4.15) for disease control rate (DCR). Moreover, patients with distant metastasis or III-IV stage had significantly higher plasma fibrinogen level (SMD: 0.20, 95% CI, 0.04-0.36; SMD: 0.31, 95% CI, 0.18-0.44, respectively). CONCLUSIONS: The summary results indicated that plasma fibrinogen was a marker of prognosis and clinicopathological characteristics in lung cancer.