Related Experiment Video
Updated: Jul 10, 2026
Implementation of In Vitro Drug Resistance Assays: Maximizing the Potential for Uncovering Clinically Relevant Resistance Mechanisms
Published on: December 9, 2015
Systematic review of comparative transcriptomic studies of cellular resistance to genotoxic stress
Z B Ismailov1, E S Belykh1, A A Chernykh2
1Institute of Biology of Komi Science Centre of the Ural Branch of the Russian Academy of Sciences, 28b Kommunisticheskaya St., Syktyvkar 167982, Russia.
Abstract:
The development of resistance by tumor cells to various types of therapy is a significant problem that decreases the effectiveness of oncology treatments. For more than two decades, comparative transcriptomic studies of tumor cells with different sensitivities to ionizing radiation and chemotherapeutic agents have been conducted in order to identify the causes and mechanisms underlying this phenomenon. However, the results of such studies have little in common and often contradict each other. We have assumed that a systematic analysis of a large number of such studies will provide new knowledge about the mechanisms of development of therapeutic resistance in tumor cells. Our comparison of 123 differentially expressed gene (DEG) lists published in 98 papers suggests a very low degree of consistency between the study results. Grouping the data by type of genotoxic agent and tumor type did not increase the similarity. The most frequently overexpressed genes were found to be those encoding the transport protein ABCB1 and the antiviral defense protein IFITM1. We put forward a hypothesis that the role played by the overexpression of the latter in the development of resistance may be associated not only with the stimulation of proliferation, but also with the limitation of exosomal communication and, as a result, with a decrease in the bystander effect. Among down regulated DEGs, BNIP3 was observed most frequently. The expression of BNIP3, together with BNIP3L, is often suppressed in cells resistant to non-platinum genotoxic chemotherapeutic agents, whereas it is increased in cells resistant to ionizing radiation. These observations are likely to be mediated by the binary effects of these gene products on survival, and regulation of apoptosis and autophagy. The combined data also show that even such obvious mechanisms as inhibition of apoptosis and increase of proliferation are not universal but show multidirectional changes.
Insights
Tumor cells develop resistance to cancer therapies, but studies on gene expression changes show little consistency. Overexpressed ABCB1 and IFITM1, and downregulated BNIP3, were common findings, suggesting complex resistance mechanisms.
Area of Science:
- Oncology
- Genomics
- Molecular Biology
Background:
- Therapeutic resistance in tumor cells significantly reduces cancer treatment efficacy.
- Comparative transcriptomic studies aim to identify mechanisms of resistance but yield inconsistent results.
- A systematic analysis of existing studies is needed to uncover common resistance pathways.
Approach:
- A meta-analysis was performed on 123 differentially expressed gene (DEG) lists from 98 published papers.
- Data were compared to identify consistent gene expression changes across studies.
- Analyses were stratified by genotoxic agent type and tumor type to assess data similarity.
Key Points:
- A very low degree of consistency was observed between DEG lists from different studies.
- Overexpression of ABCB1 (transport protein) and IFITM1 (antiviral defense protein) were the most frequent findings.
- Downregulation of BNIP3 was most common among downregulated DEGs, with differential expression patterns observed for BNIP3 and BNIP3L in response to different therapies.
Conclusions:
- Mechanisms of therapeutic resistance, including apoptosis inhibition and proliferation increase, are not universal.
- IFITM1 overexpression may contribute to resistance by stimulating proliferation and limiting exosomal communication.
- BNIP3 and BNIP3L expression changes likely play complex roles in mediating resistance through survival, apoptosis, and autophagy regulation.
