This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Other topics and Adverse effects, Subject name: Anatomy
Pentostatin acts by inhibiting 
Select and explain. 
A. RNA dependent DNA polymerase, B. Aldolase, C. Aldenosine deaminase, D. Adenylyl cyclase
C: Aldenosine deaminase
Answer: C: Aldenosine deaminase 
Explanation: Ref-Katzung 10/920 Pentostatin and cilastatin are not statins i.e. these do not act by inhibiting HMG-CoA reductase. Pentostatin acts by inhibiting adenosine deaminase. It is used for the treatment of hairy cell leukemia. Drug of choice for hairy cell leukemia is cladribine.