Institut de Biologie StructuraleGrenoble / France

Contact person(s) related to this article / VAUCLARE Pierre

DNA repair in anti-cancer drug resistance

Cancer is at present one of the leading causes of death in the world, with millions of people diagnosed with cancer every year. With the exception of surgery, most anticancer therapies (including both radio- and chemotherapy) aim to eliminate cancer cells by causing severe damage to the DNA. However, efficient repair of such damage in tumor cells represents a common mechanism of resistance to initially effective cytotoxic treatments. There is thus an increasing interest in the development of new generation anticancer drugs that target DNA repair pathways. In particular, the base excision repair (BER) pathway is an attractive target since it is responsible for removal of damaged bases resulting from oxidative, alkylating and deamination events, induced by either environmental factors, endogenous stress such as reactive oxygen species, or anticancer agents.

Our team is particularly interested in the human DNA glycosylase, hNTH1, that is responsible for recognition and removal of oxidized pyrimidines from the DNA. We and others have demonstrated that its repair activity is stimulated by a stress response factor, the multifunctional Y-box binding protein 1 (YB1), after its translocation into the nucleus in response to genotoxic stress, leading to increased resistance to the chemotherapeutic agent, cisplatin. In a recent study (Senarisoy et. al., 2020), we demonstrated that inhibition of the hNTH1-YB1 interaction can partially restore the sensitivity of MCF7 breast cancer cells to cisplatin, indicating that this interface represents a promising new drug target. For the purpose of this study, we successfully developed an original and robust, low-cost FRET-based biosensor that allowed us to efficiently screen chemical libraries to find potent inhibitors of this complex. The IC50 values of these selected compounds were then determined using an orthologous approach (AlphaScreen technology) and their molecular targets were identified by thermal shift assay. Our objective is now to decipher the mechanisms underlying the role of hNTH1 and YB1 in cisplatin resistance and to find and optimize more potent inhibitors of this complex for therapeutic use.

Members of the team

• Salvatore DE BONIS
• Fabienne HANS
• Jean-Philippe KLEMAN
• Françoise LACROIX
• Joanna TIMMINS

Techniques

• Molecular biology
• Recombinant expression and purification of proteins
• Mammalian cell culture
• Stable & transient transfections
• Förster Resonance Energy Transfer
• Confocal fluorescence microscopy
• DNA repair assays
• High-throughput screening of chemical libraries
• Thermal shift assay
• AlphaScreen technology

Collaborations

• Caroline BARETTE & Marie-Odile FAUVARQUE (CMBA, Grenoble)
• Philippe FRACHET (PIXEL team, I2SR Group, IBS)

Major publications

Hans F, Senarisoy M, Bhaskar Naidu C and Timmins J. Focus on DNA glycosylases – A set of tightly regulated enzymes with high potential as anticancer drug targets. (Review) Int. J. Mol. Sci., Special issue : Recognition of DNA lesions. (2020). 21 (23), 9226. DOI : 10.3390/ijms21239226.

Senarisoy M, Barette C, Lacroix F, De Bonis S, Stelter M, Hans F, Kleman JP, Fauvarque M-O and Timmins J. Förster resonance energy transfer-based biosensor for targeting the hNTH1-YB1 interface as a potential anti-cancer drug target. ACS Chemical Biology (2020) 15, 4, 990-1003. DOI : 10.1021/ acschembio.9b01023.

Sarre A, Stelter M, Rollo F, De Bonis S, Seck A, Hognon C, Ravanat JL, Monari A, Dehez F, Moe E and Timmins J. The three Endonuclease III variants of Deinococcus radiodurans possess distinct and complementary DNA repair activities. DNA Repair (2019) 78 p. 45-59. DOI : 10.1016/j.dnarep.2019.03.014