Characterization of resistance to VP-16 in human leukemic cell line.

Tohoku J Exp Med

Department of Internal Medicine, Tohoku University, Sendai.

Published: December 1989

Resistance mechanism was studied in the VP-16-resistant human leukemic cell line (THP-1/E) which was developed by continuous drug exposure. The drug uptake and efflux studies revealed no decrease in net cellular drug accumulation. VP-16-induced DNA single- and double-strand breaks in the whole THP-1/E cells decreased significantly compared to the sensitive counterpart as assessed by alkaline elution methods. Decrease in DNA SSBs was also observable in the isolated nuclei from the THP-1/E cells. The resistance to VP-16 in THP-1/E appeared to be independent of altered membrane permeability, and more likely to be associated with decreased VP-16-mediated DNA cleavage.

Download full-text PDF

Source
http://dx.doi.org/10.1620/tjem.159.299DOI Listing

Publication Analysis

Top Keywords

resistance vp-16
8
human leukemic
8
leukemic cell
8
thp-1/e cells
8
characterization resistance
4
vp-16 human
4
cell resistance
4
resistance mechanism
4
mechanism studied
4
studied vp-16-resistant
4

Similar Publications

Synthesis, Structural Modification, and Antismall Cell Lung Cancer Activity of 3-Arylisoquinolines with Dual Inhibitory Activity on Topoisomerase I and II.

J Med Chem

January 2025

Department of Respiratory and Critical Care Medicine, Molecularly Targeted Research and Development Laboratory, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P. R. China.

To overcome the compensatory effect between Topo I and II, one of the reasons accounting for the resistance of SCLC patients, we are pioneering the use of 3-arylisoquinolines to develop dual inhibitors of Topo I/II for the management of SCLC. A total of 46 new compounds were synthesized. Compounds (IC = 1.

View Article and Find Full Text PDF

Comprehensive Cellular Senescence Evaluation to Aid Targeted Therapies.

Research (Wash D C)

January 2025

State Key Laboratory of Genetic Engineering, National Clinical Research Center for Aging and Medicine, Huashan Hospital, Collaborative Innovation Center of Genetics and Development, Human Phenome Institute, Center for Evolutionary Biology, Shanghai Engineering Research Center of Industrial Microorganisms, School of Life Sciences, Fudan University, Shanghai 200438, China.

Drug resistance to a single agent is common in cancer-targeted therapies, and rational drug combinations are a promising approach to overcome this challenge. Many Food and Drug Administration-approved drugs can induce cellular senescence, which possesses unique vulnerabilities and molecular signatures. However, there is limited analysis on the effect of the combination of cellular-senescence-inducing drugs and targeted therapy drugs.

View Article and Find Full Text PDF

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) effectively treat EGFR-mutant lung adenocarcinoma, demonstrating initial efficacy but eventually leading to acquired resistance. Small cell transformation is a rare resistance mechanism to EGFR-TKIs in lung adenocarcinoma, which can complicate clinical diagnosis and treatment. We present a patient with lung adenocarcinoma who underwent a prior pneumonectomy and adjuvant chemotherapy and was treated with osimertinib after the recurrence of lung cancer.

View Article and Find Full Text PDF

Lung cancer continues to be the leading cause of mortality globally. Nanotechnology-mediated targeted drug delivery approach is one of the promising strategies for the treatment of lung cancer. Due to their multifactorial role, mesoporous silica nanoparticles (MSNs), have attracted a lot of attention for drug delivery.

View Article and Find Full Text PDF

Increased expression of branched-chain amino acid (BCAA) transaminase 1 (BCAT1) often correlates with tumor aggressiveness and drug resistance in cancer. We have recently reported that BCAT1 was overexpressed in a subgroup of T-cell acute lymphoblastic (T-ALL) samples, especially those with NOTCH1 activating mutations. Interestingly, BCAT1-depleted cells showed pronounced sensitivity to DNA-damaging agents such as etoposide; however, how BCAT1 regulates this sensitivity remains uncertain.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!