Development of a multi-targeted chemotherapeutic approach based on G-quadruplex stabilisation and carbonic anhydrase inhibition

Abstract

A novel class of compounds designed to hit two anti-tumour targets, G-quadruplex structures and human carbonic anhydrases (hCAs) IX and XII is proposed. The induction/stabilisation of G-quadruplex structures by small molecules has emerged as an anticancer strategy, disrupting telomere maintenance and reducing oncogene expression. hCAs IX and XII are well-established anti-tumour targets, upregulated in many hypoxic tumours and contributing to metastasis. The ligands reported feature a berberine G-quadruplex stabiliser scaffold connected to a moiety inhibiting hCAs IX and XII. In vitro experiments showed that our compounds selectively stabilise G-quadruplex structures and inhibit hCAs IX and XII. The crystal structure of a telomeric G-quadruplex in complex with one of these ligands was obtained, shedding light on the ligand/target interaction mode. The most promising ligands showed significant cytotoxicity against CA IX-positive HeLa cancer cells in hypoxia, and the ability to stabilise G-quadruplexes within tumour cells.

GRAPHICAL ABSTRACT

Keywords:

• G-Quadruplex
• carbonic anhydrase
• multitarget-directed ligands
• tumours

Author contributions

Conception, Data analysis, Investigation, Writing – original draft, Funding acquisition, AN; Investigation, Data analysis, Writing – original draft, ADP; Investigation, Data analysis, AB; Conceptualisation, Investigation, Data analysis, Writing – original draft, CB; Investigation, Formal analysis, AP; Investigation, Data analysis, TB; Investigation, Data analysis, SB; Investigation, Data analysis, SM; Investigation, Data analysis, JA; Investigation, Data analysis, BP; Investigation, Data analysis, NI; Investigation, Data analysis, SDT; Investigation, Data analysis, SA; Data analysis, Visualisation, CTS; Data analysis, Writing – original draft, Visualisation, Funding acquisition, AR; Conception, Data analysis, Funding acquisition, Writing – original draft, Visualisation, Project administration, PG. All authors agree to be accountable for all aspects of the work.

Disclosure statement

All authors except CTS report no conflict of interest. CT Supuran is Editor-in-Chief of the Journal of Enzyme Inhibition and Medicinal Chemistry. He was not involved in the assessment, peer review, or decision-making process of this paper. The authors have no relevant affiliations of financial involvement with any organisation or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Additional information

Funding

The authors acknowledge the financial support from: (i) Fondazione Intesa San Paolo [B/2021/0168] to PG; (ii) Fondazione Italiana per la Ricerca sul Cancro [IG 26313] and Ministero dell’Università e della Ricerca [PRIN P2022EPH87] to AR; Ministero dell’Università e della Ricerca [PRIN 2022HMJLN] to AN. ADP is the recipient of a postdoc fellowship from Fondazione Italiana per la Ricerca sul Cancro [26644]. SB acknowledges the Research Institute of the University of Bucharest for the ICUB Fellowship for Young Researchers.