Chemoresistance refers to the ability of cancer cells to survive and continue growing despite being exposed to chemotherapy drugs. This phenomenon poses a significant challenge in cancer treatment, as it can lead to treatment failure and disease progression. Chemoresistance can arise through various mechanisms, including the overexpression of drug efflux pumps, alterations in drug targets, activation of DNA damage repair pathways, and changes in cell signaling pathways. Understanding and overcoming chemoresistance is a critical area of research in cancer biology and oncology, as it can help improve the effectiveness of chemotherapy and ultimately improve patient outcomes.