title: Antihyperglycaemic therapies and cancer risk.
abstract: OBJECTIVE
  This review is aimed at highlighting the potential mitogenic/tumour growth-promoting or antimitogenic/tumour growth-inhibiting effects of the main antihyperglycaemic drug classes.
  
  
  METHODS
  We review and discuss the most current studies evaluating the association between antidiabetic medications used in clinical practice and malignancies as described so far.
  
  
  RESULTS
  Metformin seems to be the only antidiabetic drug to exert protective effects both on monotherapy and also when combined with other oral antidiabetic drugs or insulins in several site-specific cancers. In contrast, several other drug classes may increase cancer risk. Some reason for concern remains regarding sulphonylureas and also the incretin-based therapies regarding pancreas and thyroid cancers and the sodium glucose cotransporter-2 inhibitors as well as pioglitazone regarding bladder cancer. The majority of meta-analyses suggest that there is no evidence for a causal relationship between insulin glargine and elevated cancer risk, although the studies have been controversially discussed. For α-glucosidase inhibitors and glinides, neutral or only few data upon cancer risk exist.
  
  
  CONCLUSIONS
  Although the molecular mechanisms are not fully understood, a potential risk of mitogenicity and tumour growth promotion cannot be excluded in case of several antidiabetic drug classes. However, more large-scale, randomized, well-designed clinical studies with especially long follow-up time periods are needed to get reliable answers to these safety issues.
authors.affiliation: Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, Department of Internal Medicine, University of Tübingen, Tübingen, Germany German Centre for Diabetes Research (DZD), Tübingen, Germany.
authors.forename: Stefan Z
authors.initials: SZ
authors.lastname: Lutz
authors.affiliation: Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, Department of Internal Medicine, University of Tübingen, Tübingen, Germany German Centre for Diabetes Research (DZD), Tübingen, Germany Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Centre Munich at the University of Tübingen, Tübingen, Germany.
authors.forename: Harald
authors.initials: H
authors.lastname: Staiger
authors.affiliation: Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, Department of Internal Medicine, University of Tübingen, Tübingen, Germany German Centre for Diabetes Research (DZD), Tübingen, Germany Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Centre Munich at the University of Tübingen, Tübingen, Germany Division of Nutritional and Preventive Medicine, Department of Internal Medicine, University of Tübingen, Tübingen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Fritsche
authors.affiliation: Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, Department of Internal Medicine, University of Tübingen, Tübingen, Germany German Centre for Diabetes Research (DZD), Tübingen, Germany Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Centre Munich at the University of Tübingen, Tübingen, Germany hans-ulrich.haering@med.uni-tuebingen.de.
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Häring
mesh_terms: D000818:Animals; D003920:Diabetes Mellitus / Q000188:drug therapy; D006801:Humans; D007004:Hypoglycemic Agents / Q000009:adverse effects*; D009369:Neoplasms / Q000139:chemically induced* / Q000401:mortality
chemical_list: D007004:Hypoglycemic Agents
keywords: Diabetes; antidiabetic therapy; insulin; malignancy; tumour growth