Purpose “Driver gene-negative” non-small cell lung cancer (NSCLC) currently has no approved targeted drug, due to the lack of common actionable driver molecules. Even though miRNAs play crucial roles in various malignancies, their roles in “driver gene-negative” NSCLC keep unclear. Methods miRNA expression microarrays were utilized to screen miRNAs associated with “driver gene-negative” NSCLC malignant progression. Quantitative real-time PCR (RT-qPCR) and in situ hybridization (ISH) were employed to validate the expression of miR-4739, and its correlation with clinicopathological characteristics was analyzed in tumor specimens using univariate and multivariate analyses. The biological functions and underlying mechanisms of miR-4739 were investigated both in vitro and in vivo. Results our research demonstrated, for the first time, that miR-4739 was substantially increased in “driver gene-negative” NSCLC tumor tissues and cell lines, and overexpression of miR-4739 was related to clinical staging, metastasis, and unfavorable outcomes. Functional experiments discovered that miR-4739 dramatically enhanced tumor cell proliferation, migration, and metastasis by promoting the epithelial-to-mesenchymal transition (EMT). Meanwhile, miR-4739 can be transported from cancer cells to the site of vascular epithelial cells through exosomes, consequently facilitating the proliferation and migration of vascular epithelial cells and inducing angiogenesis. Mechanistically, miR-4739 can activate Wnt/β-catenin signaling both in tumor cells and vascular epithelial cells by targeting Wnt/β-catenin signaling antagonists APC2 and DKK3, respectively. Conclusion Our work identifies a valuable oncogene, miR-4739, that accelerates malignant progression in “driver gene-negative” NSCLC and serves as a potential therapeutic target for this group of tumors.
Current guidelines recommend adjuvant chemotherapy (ACT) for stage II colorectal cancer (CRC) patients by using clinical high risk factors, with which circulating tumor cells (CTCs) were not considered. Here, an assessment to detect CTCs based on subtraction enrichment mediated by magnetic beads conjugated with CD45, immunofluorescence staining of CK, and fluorescence in situ hybridization of CEP8 is established. Both CEP8- and CK-positive CTCs have the potential to improve the risk stratification of stage II CRC patients. Patients with preoperative CTCs of ≥4 had a significantly higher recurrence risk than those with preoperative CTCs of <4 in two external validation cohorts (P < 0.0001). In the subgroup with clinical high risk, when preoperative CTCs were <4, patients did not benefit from ACT (P = 0.5764); however, when preoperative CTCs were ≥4, patients received benefit from ACT (P = 0.0064). Additionally, regardless of clinical risk status and preoperative CTC levels, if postoperative CTC levels were ≥4 for more than three consecutive time points (monitoring time interval, 2-6 months), the recurrence rate was 100%. Our findings suggested that the subtraction enrichment of CTCs could provide a reliable method to stratify the recurrence risk and make therapeutic decisions after surgery in stage II CRC patients.