TGFB1 and cancer: Thus, knockout of the β6 gene (itgb6) in mice was associated with a mild inflammatory response in skin and lung (Huang et al. 1996) and with a propensity for the spontaneous formation of certain cancers in up to 25 % of itgb6-null mice (Ludlow et al. 2005), patterns that mimicked a mild form of global TGFβ1 knockout mouse (Shull et al. 1992).