Abstract 3804: Molecular changes induced by the curcumin biphenyl analogue D6 in melanoma cells

Abstract

Abstract Malignant melanoma (MM) is one of the most aggressive cancers that affect humans. It is the most common and fatal skin cancer, with an incidence that is critically increasing in Western populations (15 times in the last 40 years) and for which, in the advanced stages, there is no effective therapy. The search for new compounds able to control it is therefore essential. The hydroxylated biphenyl compound (3E,3′E)-4,4′-(5,5′,6,6′-tetramethoxy-[1,1′-biphenyl]-3,3′-diyl)bis(but-3-en-2-one), namely D6, a structural analogue of curcumin, showed a strong antitumor activity on MM cells both in vitro and in vivo, as we have recently described [1]. The mechanisms of action of this compound are not clear yet, but it inhibits cancer cells growth by inducing apoptosis without affecting normal fibroblasts growth. Firstly we investigated the ability of D6 to enter cells by Liquid Chromatography-Mass Spectrometry (LC-MS) analysis. The LC-MS data showed a quick cellular uptake of D6 with a maximum peak after about 2 hours. To investigate on the effects of D6 treatment on the cell cycle progression in MM cells, we performed flow cytometry analysis, which evidenced a cell cycle arrest in the G2/M phase. Gene expression profiles analysis using Illumina® high-density microarrays, was carried out on D6 treated MM cells and normal fibroblasts allowing the identification of 599 transcripts whose expression was modulated by D6 treatment in MM cells but not in normal fibroblast. The analysis of results, performed by Ingenuity Pathway Analysis software, showed the centrality of CDKN1A gene, encoding p21, a major negative cell cycle regulator, which was strongly over expressed, while cyclin B and cdc25 phosphatase, showed both to be down modulated. Other genes which expression interestingly appeared to be decreased by D6 activity were the oncogenes c-kit and PI3K, suggesting a down regulation of both c-kit mediated and PI3K/AKT signal transduction pathways driving to cell proliferation. Modulation of expression of these specific genes has been confirmed at a protein level by western blotting analysis. Moreover our results pointed out an upregulation of several heat shock family genes, which is probably due to a curcumin related anti inflammatory effect of D6. The preliminary results of these analysis show that D6 induces molecular changes in MM cells at both gene expression and protein levels, involving major cell proliferation regulatory pathways. [1] Marina Pisano et al. (2010).Enhanced anti-tumor activity of a new curcumin-related compound against melanoma and neuroblastoma cells. Molecular Cancer, 9:137. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3804. doi:1538-7445.AM2012-3804