Related Experiment Video

Updated: Aug 8, 2026

Demonstrating a Multi-drug Resistant Mycobacterium tuberculosis Amplification Microarray
07:35

Demonstrating a Multi-drug Resistant Mycobacterium tuberculosis Amplification Microarray

Published on: April 25, 2014

Analysis of dihydrofolate reductase gene amplification in a methotrexate-resistant human tumor cell line

P S Meltzer, Y C Cheng, J M Trent

    Cancer Genetics and Cytogenetics
    |August 1, 1985
    PubMed

    Insights

    Methotrexate resistance in human KB tumor cells is linked to increased amplification of the dihydrofolate reductase gene. This gene amplification is localized to a specific region on chromosome 10q in resistant cell lines.

    Area of Science:

    • Cytogenetics
    • Molecular Biology
    • Cancer Research

    Background:

    • The KB tumor cell line is a model for studying drug resistance.
    • Methotrexate is a chemotherapy agent targeting dihydrofolate reductase.

    Purpose of the Study:

    • To investigate the genetic basis of methotrexate resistance in human KB tumor cells.
    • To characterize the changes in the dihydrofolate reductase gene in resistant subclones.

    Main Methods:

    • Cytogenetic analysis of tumor cell lines.
    • Molecular biologic studies including gene amplification analysis.
    • Localization of gene sequences using chromosomal analysis.

    Main Results:

    • Progressively methotrexate-resistant subclones showed increased amplification of the dihydrofolate reductase gene.
    • Dihydrofolate reductase gene sequences were localized to a homogeneously staining region on chromosome 10q.

    Conclusions:

    • Gene amplification of dihydrofolate reductase is a key mechanism of methotrexate resistance in KB cells.
    • Chromosomal abnormalities, specifically on 10q, are associated with this drug resistance.

    More Related Videos

    Using RNA-sequencing to Detect Novel Splice Variants Related to Drug Resistance in In Vitro Cancer Models09:58

    Using RNA-sequencing to Detect Novel Splice Variants Related to Drug Resistance in In Vitro Cancer Models

    Published on: December 9, 2016

    Multi-Gene Single Nucleotide Polymorphism Detection in Gastric Cancer Based on Ion Semiconductor Sequencing Platform06:21

    Multi-Gene Single Nucleotide Polymorphism Detection in Gastric Cancer Based on Ion Semiconductor Sequencing Platform

    Published on: May 10, 2024

    Related Concept Videos

    Treatment Resistant Cancers02:56

    Treatment Resistant Cancers

    Cancer is the second leading cause of death in the United States. A cancer cell is genetically unstable and hence can mutate faster. They can also modify their microenvironment and escape immune surveillance. The difficulties in treating cancer are further compounded by the emergence of rapid resistance to anticancer drugs. The most common ways to attain resistance in cancer cells include alteration in drug transport and metabolism, modification of drug target, elevated DNA damage response, or...
    Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase01:11

    Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase

    Genetic polymorphisms in drug targets have emerged as critical determinants of interindividual variability in drug response and toxicity. Pharmacogenomic investigations increasingly focus on identifying these variations to personalize and optimize therapeutic interventions. A drug target may be a receptor, enzyme, or signaling protein involved in pharmacologic responses or disease-related pathways. While early pharmacogenetic studies focused primarily on drug metabolism, current research...