INS and type 2 diabetes mellitus: No association between insulin therapy and clinicopathological subtypes was noted, even though insulin use in T2DM may induce oestrogen (ER) and progesterone receptors expression.36 Conversely, a systematic review of in vitro, animal and human studies found no evidence of increased BC risk with commercially available insulin analogues and human insulin.37 Conflicting findings were reported by other investigators.