Answer:
The resistance of cancer cells to medications can be classified as intrinsic, when the tumors do not respond to chemotherapy and the treatment has no effect on the disease. Another type of resistance is that acquired, when a resistant cell clone appears, which induces an increase in the tumor that cannot be controlled by drugs.
Explanation:
The development of chemotherapy resistance in people with cancer has a multicausal effect, and its origin may be due to different factors of pharmacological or cellular types. The way in which the drug is distributed throughout the body, its catabolism or the location of the tumor, all this leads to the low bioavailability of the drug. This type of resistance is known as pharmacological resistance.
Some cellular resistance mechanisms are as follows:
-Alteration in intracellular metabolism.
-Alteration in the intracellular distribution.
-A decrease or alteration of the topoisomerase II enzyme.
-Much greater increase in DNA repair characteristic.