CDA and familial pancreatic carcinoma: Interestingly, scientists have observed a similar phenomenon in mycoplasma, which can encode the CDD to inhibit the antitumor activity of gemcitabine in mycoplasma-infected mouse tumor cells, and this inhibition can be relieved by tetrahydrouridine (a cytidine deaminase inhibitor) or antibiotics such as tetracycline 153, suggesting that these bacteria may be related to chemotherapy resistance in pancreatic cancer.