title: [Metformin impact on purine metabolism in breast cancer].
abstract: Large-scale epidemiological and clinical studies have demonstrated the efficacy of metformin in oncology practice. However, the mechanisms of implementation of the anti-tumor effect of this drug there is still need understanding. In this study we have investigated the effect of metformin on the activity of adenosine deaminase and respectively adenosinergic immunosuppression in tumors and their microenvironment. The material of the study was taken during surgery of breast cacer patients receiveing metformin, and also patients which did not take this drug. The adenosine deaminase activity and substrate (adenosine) and products (inosine, hypoxanthine) concentrations were determined by HPLC. Results of this study suggest that metformin significantly alters catabolism of purine nucleotides in the node breast adenocarcinoma tisue. However, the metformin-induced increase in the adenosine deaminase activity is not sufficient to reduce the level of adenosine in cancer tissue. Thus, in metformin treated patients the adenosine concentration remained unchanged, and inosine and hypoxanthine concentration significantly increased.
authors.affiliation: Gorky Donetsk National Medical University, Donetsk, Ukraine.
authors.forename: O P
authors.initials: OP
authors.lastname: Shatova
authors.affiliation: Gorky Donetsk National Medical University, Donetsk, Ukraine.
authors.forename: Eu V
authors.initials: EV
authors.lastname: Butenko
authors.affiliation: Gorky Donetsk National Medical University, Donetsk, Ukraine.
authors.forename: Eu V
authors.initials: EV
authors.lastname: Khomutov
authors.affiliation: Gorky Donetsk National Medical University, Donetsk, Ukraine.
authors.forename: D S
authors.initials: DS
authors.lastname: Kaplun
authors.affiliation: Gorky Donetsk National Medical University, Donetsk, Ukraine.
authors.forename: I Eu
authors.initials: IE
authors.lastname: Sedakov
authors.affiliation: Gorky Donetsk National Medical University, Donetsk, Ukraine.
authors.forename: I I
authors.initials: II
authors.lastname: Zinkovych
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D008687:Metformin / Q000009:adverse effects* / Q000627:therapeutic use; D008875:Middle Aged; D011687:Purines / Q000378:metabolism*
chemical_list: D007004:Hypoglycemic Agents; D011687:Purines; D008687:Metformin
keywords: adenosine; adenosine deaminase; breast cancer; hypoxanthine; inosine; metformin