Multidrug Resistance Mechanisms in Cancer Therapeutics

Multidrug resistance (MDR) remains one of the foremost obstacles to successful cancer therapy, arising when malignant cells evade the cytotoxic effects of structurally and functionally distinct agents. Central to this phenomenon are ATP-binding cassette (ABC) transporters, notably P-glycoprotein and multidrug resistance-associated proteins, which actively efflux chemotherapeutics and targeted inhibitors, reducing intracellular drug concentrations. Additional mechanisms include enhanced DNA damage repair, altered drug metabolism through phase I and II enzymes, suppression of apoptosis via dysregulation of BCL-2 family proteins, epigenetic modifications that silence drug-sensitivity genes, and tumour heterogeneity that fosters drug-tolerant subclones. Crosstalk between survival pathways such as PI3K/AKT/mTOR and microenvironmental factors including hypoxia further amplifies resistance. A holistic understanding of these interdependent processes is essential for the design of combination regimens that counteract efflux, restore programmed cell death and inhibit compensatory signalling networks.

Research from Nature Portfolio

Recent studies have illuminated the role of the ABCC1 transporter in modulating the efficacy of BCL-2 inhibitors in acute myeloid leukaemia. Functional genomic screens demonstrated that ABCC1 overexpression diminishes intracellular levels of Venetoclax, whereas its genetic or pharmacologic inhibition re-sensitises resistant cells and potentiates apoptotic responses. Complementary work has unveiled novel small-molecule inhibitors of P-glycoprotein that bind the nucleotide-binding domain, thereby preventing drug efflux without being themselves transported substrates. In vitro and three-dimensional microtumour models confirm that co-administration with standard chemotherapeutics enhances drug retention, reduces cell viability and curbs motility in resistant ovarian and prostate cancer lines, offering promising leads for clinical translation.

Multidrug Resistance Mechanisms in Cancer Therapeutics publication trend

The graph below shows the total number of articles in multidrug resistance mechanisms in cancer therapeutics across all publications each year (not limited to Nature Index journals).

Technical terms

ATP-binding cassette (ABC) transporters: Membrane proteins that utilise ATP hydrolysis to translocate a wide range of substrates, including chemotherapeutic agents, across cellular membranes, thereby mediating drug efflux.

Multidrug resistance (MDR): The capacity of cancer cells to resist structurally and mechanistically diverse therapeutic agents, often through combined alterations in transport, metabolism, repair and survival pathways.

Apoptosis: Programmed cell death regulated by intrinsic and extrinsic signals, with BCL-2 family proteins controlling mitochondrial outer membrane permeabilisation.

PI3K/AKT pathway: A key intracellular signalling cascade that promotes cell survival, growth and metabolism; aberrant activation contributes to chemoresistance by multiple downstream effectors.

Glutathione metabolism: Cellular redox network centred on glutathione conjugation and recycling; influences drug detoxification and transporter-mediated drug export.

References

1. ABCC1 and glutathione metabolism limit the efficacy of BCL-2 inhibitors in acute myeloid leukemia. Nature Communications (2023).
2. Structure and Mechanism of Human ABC Transporters. Annual Review of Biophysics (2023).
3. Mechanisms of Multidrug Resistance in Cancer Chemotherapy. International Journal of Molecular Sciences (2020).
4. PI3K/AKT pathway as a key link modulates the multidrug resistance of cancers. Cell Death & Disease (2020).
5. Targeted inhibitors of P-glycoprotein increase chemotherapeutic-induced mortality of multidrug resistant tumor cells. Scientific Reports (2018).