# Various anthracyclines exhibit differential cytotoxic effects related to CBR1-induced resistance in lung cancer cells

## TL;DR

This study shows how different anthracycline drugs react to a protein called CBR1, which can reduce their effectiveness in treating lung cancer.

## Contribution

The study reveals that CBR1 affects anthracyclines differently, with aclarubicin being the most impacted despite slow CBR1 activity.

## Key findings

- CBR1 overexpression significantly alters the cytotoxic effects of various anthracyclines in lung cancer cells.
- Aclarubicin shows the highest dependency on CBR1 despite having low reaction velocity with the enzyme.
- The study identifies differential susceptibility of anthracyclines to CBR1-mediated resistance.

## Abstract

Anthracyclines are widely used anticancer agents with a complex mechanism of action involving topoisomerase II inhibition and DNA intercalation. Despite their clinical efficacy, their use is limited by cancer cell resistance, linked to the formation of secondary alcohol metabolites via carbonyl reductase 1 (CBR1)-mediated reduction. These metabolites exhibit reduced anticancer activity, positioning CBR1 as significant factor in determining therapy outcomes. The study aimed to elucidate the role of CBR1 in mediating the differential responses of various anthracyclines in cancer cells. The role of CBR1 in cancer resistance against five anthracyclines: doxorubicin, daunorubicin, epirubicin, idarubicin, and aclarubicin, was examined in A549 lung cancer cells transduced with the CBR1. Anthracyclines were found to present significant differences in activity related to CBR1 overexpression. Surprisingly, aclarubicin was the most dependent on CBR1 among the tested compounds, while it exhibited a low reaction velocity when catalyzed by recombinant CBR1. The findings reveal critical differences in anthracycline susceptibility to CBR1, offering insights into resistance mechanisms.