Compounds 1 and 2 have no effect on the HIF-1α protein level and cell proliferation in HCT-116.

<p>(A) Western blotting analysis of the total protein extracts from HCT-116 cells after treatment with compounds <b>1</b> and <b>2</b> probed with HIF-1α and β-actin antibodies. Histograms report the densitometric values of HIF-1α/β-actin ratio. The densitometric values represent the mean ± SDs of three independent experiments; (B) the cell proliferation was measured by MTT assay in HCT-116 cells 24 h after treatment with compounds <b>1</b> and <b>2</b>. All values represent the mean ± SDs of three independent experiments and are expressed as a percentage compared to 100% of control cells; (C) Clonogenic survival assay in HCT-116 after treatment with L-carnosine (50 mM) or compounds <b>1</b> and <b>2</b> (0.5 mM) with respect to untreated cells.