Identification of a Potent and Selective CDK9 Degrader as a Targeted Therapeutic Option for the Treatment of...

Area of Science:

• Oncology
• Molecular Biology
• Drug Discovery

Background:

• Small-cell lung cancer (SCLC) presents a major health concern with limited treatment options.
• Advanced stage diagnosis and lack of effective targeted therapies contribute to high SCLC mortality.
• Targeting specific molecular pathways is crucial for developing novel SCLC treatments.

Purpose of the Study:

• To develop a potent and selective CDK9 degrader for SCLC treatment.
• To evaluate the therapeutic efficacy and pharmacokinetic properties of the novel compound C3.
• To explore the potential of targeted protein degradation as a strategy for SCLC.

Main Methods:

• PROTAC technology was used to modify a CDK9 inhibitor (AT-7519) into a degrader (C3).
• Apoptosis induction was assessed in various SCLC cell lines.
• In vivo tolerance, oral bioavailability, and anti-proliferative effects in mini-PDX models were evaluated.

Main Results:

• C3 induced apoptosis in SCLC cell lines at low nanomolar concentrations.
• C3 exhibited favorable in vivo tolerance and adequate oral bioavailability.
• PROTAC C3 significantly reduced tumor cell proliferation in patient-derived mini-PDX models.

Conclusions:

• Targeted degradation of CDK9 represents a promising therapeutic strategy for SCLC.
• C3 demonstrates significant anti-cancer activity and favorable drug-like properties.
• The study provides a framework for optimizing PROTAC molecules for enhanced selectivity and bioavailability.