Plasma ctDNA enhances the tissue-based detection of oncodriver mutations in colorectal cancer.

PURPOSE: The advent of circulating tumor DNA (ctDNA) technology has provided a convenient and noninvasive means to continuously monitor cancer genomic data, facilitating personalized cancer treatment. This study aimed to evaluate the supplementary benefits of plasma ctDNA alongside traditional tissue-based next-generation sequencing (NGS) in identifying targetable mutations and tumor mutational burden (TMB) in colorectal cancers (CRC). METHODS: Our study involved 76 CRC patients, collecting both tissue and plasma samples for NGS. We assessed the concordance of gene mutational status between ctDNA and tissue, focusing on actionable genes such as KRAS, NRAS, PIK3CA, BRAF, and ERBB2. Logistic regression analysis was used to explore variables associated with discordance and positive mutation rates. RESULTS: In total, 26 cancer-related genes were identified. The most common variants in tumor tissues and plasma samples were in APC (57.9% vs 19.7%), TP53 (55.3% vs 22.4%) and KRAS (47.4% vs 43.4%). Tissue and ctDNA showed an overall concordance of 73.53% in detecting actionable gene mutations. Notably, plasma ctDNA improved detection for certain genes and gene pools. Variables significantly associated with discordance included gender and peritoneal metastases. TMB analysis revealed a higher detection rate in tissues compared to plasma, but combining both increased detection. CONCLUSIONS: Our study highlights the importance of analyzing both tissue and plasma for detecting actionable mutations in CRC, with plasma ctDNA offering added value. Discordance is associated with gender and peritoneal metastases, and TMB analysis can benefit from a combination of tissue and plasma data. This approach provides valuable insights for personalized CRC treatment.

Knockdown of ZEB1 Inhibits Hypertrophic Scarring through Suppressing the Wnt/ß-catenin Signaling Pathway in a Mouse Model.

BACKGROUND: Hypertrophic scars (HS) cause functional impairment and cosmetic deformities following surgeries or burns (30% to 94%). There is no target therapy yet because the pathogenesis of HS progression is not well-known. In tissue fibrosis, Zinc finger E-box binding homeobox 1 (ZEB1) abnormal upregulation is an important cause for extracellular matrix (ECM) overexpression, which is the main molecular change in HS. Therefore, we hypothesized that ZEB1-knockdown inhibits HS formation. METHODS: ZEB1 expression in human HS and TGF-ß1-induced fibroblasts were identified by PCR and western blotting. ZEB1 was knockdown by siRNA in HS fibroblasts (HSFs) and mouse HS model (C57/BL6, male, 8-12 weeks). After 8-hour-transfection, HSFs were subjected to PCR, western blotting and CCK-8, apoptosis, migration and contraction assays. Mice HS were analyzed by HE staining, PCR and western blotting after 56 days. RESULTS: ZEB1 was upregulated in HS tissue (2.0-fold; p < 0.001). ZEB1 knockdown inhibited HSFs activity (0.6 to 0.7-fold; p < 0.001), the expression of fibrotic markers (0.4 to 0.6-fold; p < 0.001) and ß-catenin, cyclinD1 and c-Myc expression (0.5-fold; p < 0.001). In mouse HS models, HS skin thickness was thinner (1.60 ± 0.40 mm vs. 4.04 ± 0.36 mm; p < 0.001) after ZEB1 knockdown. CONCLUSIONS: Knockdown of ZEB1 inhibits HS formation both in vitro and in vivo. However, this is an in vitro/mouse model and more validation is needed. CLINICAL RELEVANCE STATEMENT: The discovery of ZEB1 as a mediator of HS formation might be a potential therapeutic target in HS treatment.