Preliminary SAR on indole-3-carbinol and related fragments reveals a novel anticancer lead compound against resistant glioblastoma cells.

The prognosis for glioblastoma patients is, at best, poor, with the median time of survival after diagnosis measured in months. As such, there is much need for the rapid development of potent and novel treatments. Herein, we report our preliminary findings on the SAR of a series of indole-3-carbinol and related fragments and reveal a potent lead with low micromolar activity against a particularly resistant glioblastoma cell culture, providing a new platform for future development of a new therapy in this area.

Preliminary biological evaluation and mechanism of action studies of selected 2-arylindoles against glioblastoma.

A series of related 2-arylindoles have been evaluated for their anticancer activity against a range of glioblastoma cell lines using a number of different cell-based assays to determine cell viability after treatment with the compounds. The best indoles, which showed comparable activity to cisplatin against a U87MG cell line in the MTS assay, were taken forward and initial studies suggest that their mechanism of action is consistent with the generation of reactive oxygen species followed by autophagic cell death. Furthermore, activity was also observed in glioblastoma short-term cell cultures for the best lead compound and in some cases gave low micromolar IC50s.

Towards identifying potent new hits for glioblastoma.

Glioblastoma is a devastating disease of the brain and is the most common malignant primary brain tumour in adults. The prognosis for patients is very poor with median time of survival after diagnosis measured in months, due in part to the tumours being highly aggressive and often resistant to chemotherapies. Alongside the ongoing research to identify key factors involved in tumour progression in glioblastoma, medicinal chemistry approaches must also be used in order to rapidly establish new and better treatments for brain tumour patients. Using a computational similarity search of the ZINC database, alongside traditional analogue design by medicinal chemistry intuition to improve the breadth of chemical space under consideration, six new hit compounds (14, 16, 18, 19, 20 and 22) were identified possessing low micromolar activity against both established cell lines (U87MG and U251MG) and patient-derived cell cultures (IN1472, IN1528 and IN1760). Each of these scaffolds provides a new platform for future development of a new therapy in this area, with particular promise shown against glioblastoma subtypes that are resistant to conventional chemotherapeutic agents.