Abstract 1289: The synthetic peptide CIGB-300 inhibits nuclear factor κB (NF-κB) affecting the survival and chemoresistance of human lung cancer cells

• Published in: Cancer research (Chicago, Ill.) Ill.), 2016-07, Vol.76 (14_Supplement), p.1289-1289
• Main Authors: Cirigliano, Stéfano M., Díaz Bessone, María Inés, Flumian, Carolina, Berardi, Damián E., Perea, Silvio, Bal De Kier Joffé, Elisa, Farina, Hernán, Todaro, Laura, Urtreger, Alejandro
• Format: Article
• Language: English
• ISSN: 0008-5472; 1538-7445
• DOI: 10.1158/1538-7445.AM2016-1289

Lung cancer is the leading cause of cancer deaths worldwide and despite significant progress, current therapies are limited in efficacy. The CK2 Ser/Thr kinase has been historically linked with cancer. It is involved in cell proliferation, survival and apoptosis by modulating diverse signaling pathways, including Wnt and NF-κB among the most relevant. CIGB-300 is an antitumor peptide with a novel mechanism of action, capable of binding to CK2 substrates thus preventing the enzyme activity. Previously, we have determined that CIGB-300 induces apoptosis through caspase-3 activation in different lung cancer cell lines. Moreover, CIGB-300 strongly inhibited RelA/NF-κB (p65) nuclear translocation, even in the presence of a phorbol-ester activating stimulus. NF-κB activation is known to reduce chemotherapy efficiency in different malignancies, including lung cancer. Based on this evidence, we hypothesize that supplementing cisplatin with CIGB-300 would improve the treatment efficiency. Indeed, we observed by Western blot that nuclear p65 levels were highly increased after treating human NCI-H125 cells with cisplatin. Moreover, when cells were treated with cisplatin plus CIGB-300, NF-κB activation was completely abolished. Therefore, the CIGB-300 effect on NF-κB signaling pathway prevails over cisplatin. These promising results on NF-κB inhibition led us to evaluate the combined treatment in chemoresistant setting. For this purpose we developed a cisplatin resistant A549 lung cancer cell line (A549-Rcisp) by the chronic administration of cisplatin during six months. A549-Rcisp viability was 40% higher than parental cells, confirming the cisplatin-acquired resistance. Remarkably, cisplatin resistant cells showed a significant increase in CIGB-300 sensitivity as compared to the parental cell line (p