# Synthesis and Biological Evaluation of a Novel Dual-Targeting Small Molecule Drug Conjugate Modulating the Crosstalk between α5β1 Integrin and MDM2 in Glioblastoma

## TL;DR

A new drug targeting two proteins linked to glioblastoma was developed and shown to stop cancer cell growth and reactivate a key tumor suppressor.

## Contribution

A novel dual-targeting small molecule drug conjugate was designed to modulate the crosstalk between α5β1 integrin and MDM2 in glioblastoma.

## Key findings

- The drug conjugate retained antiproliferative activity in glioblastoma cells.
- It induced p53 reactivation with minimal MDM2 induction.
- It caused cell cycle redistribution, suggesting a unique mechanism of action.

## Abstract

Negative crosstalk
between α5β1 integrin
and the p53-MDM2
regulatory axis contributes to glioblastoma progression and therapeutic
resistance. To explore the potential of dual inhibition of these two
biological targets, the dual targeting small molecule drug conjugate
(SMDC) (1) was designed by coupling the MDM2 inhibitor
SAR405838 to a selective α5β1 integrin ligand cyclo(phg-isoDGR-k) (7) through a stable chemical linker. The resulting conjugate
retained antiproliferative activity in U87-MG glioblastoma cells and
induced p53 reactivation with minimal MDM2 induction. Cell cycle distribution
analysis revealed a redistribution of cells from the G0/G1 phase to
the G2/M phase exclusively upon treatment with conjugate 1, suggesting that a different mechanism of action is engaged. These
findings support the potential of this dual-targeting approach through
a dual-targeting SMDC as a promising therapeutic strategy against
high-grade glioma overexpressing the α5β1 integrin receptor.