PPARG and cancer: Simultaneously, Yang and coworkers [15] have shown that PPARγ knockdown by siRNA did not counteract theanti-invasive features of troglitazone using human ovarian carcinoma ES-2cells, underscoring the idea that the PPARγagonists counteract cancer cell migration by a yet unknown off-target activity.To validate these preliminary findings, we analyzed the effects of a troglitazonederivative, Δ2-troglitazone, which has been shown to be PPARγ-inactive [11, 31, 32].