TYMP and frontotemporal dementia: Since DNA MMR-deficient cells were shown to be sensitive to FTD despite being resistant to 5-FU, we next examined whether 5-FU-refractory cells were also sensitive to FTD, since TAS-102, which consists of FTD and tipiracil hydrochloride (a thymidine phosphorylase inhibitor) had been clinically shown to be effective for patients with metastatic CRC whose diseases are refractory to fluorouracil.