Mechanisms of acquired tumor drug resistance

Area of Science:

• Oncology
• Cancer Biology
• Pharmacology

Background:

• Systemic cancer therapy frequently reduces tumor size but seldom eradicates all malignant cells.
• Key factors contributing to therapy failure include drug efflux, cancer stem cell (CSC) persistence, epithelial-mesenchymal transition (EMT), and reduced apoptosis.
• Tumor resistance can arise from pathway-specific mechanisms restoring signaling cascades, genetic alterations like mutations, or epigenetic changes.

Purpose of the Study:

• To review the multifaceted causes of cancer therapy failure and the emergence of drug resistance.
• To highlight that drug resistance can be inherent in pre-existing cell populations, not solely from new mutations.
• To discuss strategies for overcoming resistance and the challenges in clinical monitoring of resistant tumor evolution.

Main Methods:

• Literature review of studies on cancer drug resistance mechanisms.
• Analysis of common causes of therapy failure, including CSCs, EMT, and apoptosis evasion.
• Examination of resistance acquisition pathways and therapeutic strategies.

Main Results:

• Cancer drug resistance is a complex phenomenon driven by various cellular and molecular mechanisms.
• Pre-existing, therapy-resistant cells within tumors can drive disease progression even without new mutations.
• Combinatorial, sequential, and adaptive therapies show promise in prolonging treatment efficacy.

Conclusions:

• Addressing drug resistance is critical for improving cancer treatment efficacy.
• Developing methods for real-time monitoring of tumor phenotype evolution in patients is a significant clinical challenge.
• Further research into inherent resistance mechanisms and advanced therapeutic strategies is warranted.