Human Health and Diseases Question 93
93. Which of the following statements is not true for cancer cells in relation to mutations? [2016]
(a) Mutations in proto-oncogenes accelerate the cell cycle.
(b) Mutations destroy telomerase inhibitor.
(c) Mutations inactive the cell control.
(d) Mutations inhibit production of telomerase.
Show Answer
Answer : d
Hints & Solutions
(d) Telomerase production is increased in cancer. Telomerase has been examined in hundreds of studies as a potentially sensitive biomarker for screening, early cancer detection, prognosis or in monitoring as an indication of residual disease. The enzyme telomerase adds TTAGGG repeats onto mammalian telomeres, which prevents their shortening. The activation of telomerase in malignant cancers seems to be an important step in tumorigenesis, whereby the cell gains the ability of indefinite proliferation to become immortal. Telomeres represent ends of all eukaryotic chromosomes and serve specialized biological role in maintaining genomic integrity by preventing end fusions and degradation. Various protein complexes associate with telomeres to either protect them from DNA damage machinery or maintain telomere length homeostasis.
