Dynamic ctDNA-based analysis of drug-resistant gene alterations at RAS/BRAF wild-type metastatic colorectal cancer patients after cetuximab plus chemotherapy as the first-line treatment.

Background: The purpose of this study was to explore the dynamic changes of genomic mutations and their correlations with the efficacy in metastatic colorectal cancer (mCRC) patients treated with cetuximab plus mFOLFOX as the first-line treatment.

Methods: We included mCRC patients from January 2018 to October 2020 as a studied cohort which were treated with cetuximab plus mFOLFOX as first line therapy. Blood samples were collected for circulating tumor DNA (ctDNA) test at three timepoints: before the first-line therapy(baseline), at the time of first-line progression and at the time of second-line progression.

Noninvasive Imaging of Ras Activity by Monomolecular Biosensor Based on Split-Luciferase Complementary Assay.

Deregulated activity of Ras GTPases has been observed in many types of human cancers, and contributes to the diverse aspects of carcinogenesis. Although the significance in tumorigenesis has been widely accepted and many therapeutic drugs are under development, little attention has been dedicated to the development of sensors for the Ras activity in vivo. Therefore, based on the split firefly luciferase complementation strategy, we developed a monomolecular bioluminescent biosensor to image endogenous Ras activity in living subject.

[The effect of eukaryotic expression plasmid ARHI on gastric cancer].

Objective: To study the effect of expressed aplasia ras homolog member I (ARHI) on the malignant biological behaviors of gastric cancer including the proliferation, migration and invasion of the cell.

Methods: The eukaryotic expression plasmid of ARHI was constructed and transfected into MKN-28 cell with lipofectamine 2000 as pEGFP-ARHI group, transfected with pEGFP-N1 as pEGFP-N1 group, and untreated MKN-28 as control group. The expression of ARHI was detected by Western blotting and fluorescence microscope.