An Alternative Fixative to Formalin Fixation for Molecular Applications: The RCL2-CS100 Approach

Molecular analysis of tissue lesions is increasingly used in laboratories to identify new prognostic and therapeutic markers. Formalin has long been the tissue fixative of choice in the laboratories of pathology, as it preserves tissue morphology allowing accurate histological diagnosis. However, formalin is highly toxic and alters nucleic acids and protein integrity, so that new fixatives are critically needed that would allow both morphological and molecular analysis on the same tissue specimen. Recently, we found RCL2^� -CS100, a noncross-linking fixative, to display interesting performances regarding tissue morphology and DNA, RNA, and protein quality. We adapted RCL2 tissue fixation protocol so it could be used on a routine and automated laboratory basis, still preserving its good performances. This protocol will be described in detail in the following review.