Abstract 4068: The potent quadruplex-binding compound SOP1812 shows potent anti-proliferative activity in a prostate cancer cell panel and anti-tumor activity in an in vivo model of metastatic prostate cancer

Abstract

Abstract The compound SOP1812, a tetra-substituted naphthalene diimide (ND) derivative has been designed as a potent compound for targeting quadruplex sequences in cancer genes. It has been previously disclosed to have single-digit nM anti-proliferative activity in a panel of human cancer cell lines (Ahmed et al., ACS Med Chem Lett, 2020, 11, 1634-1644). It also has significant anti-tumor activity in several models for pancreatic cancer. We have also previously shown that two early-generation ND derivatives are active in both androgen-positive and negative prostate cancer cell lines (Mitchell et al, Biochemistry, 2013, 32, 1429-1436) and that these compounds down-regulate the transcription of quadruplex-containing genes such as c-MYC. We now report that this compound also shows significant anti-proliferative activity in several prostate cancer cell lines, notably with a GI50 value of 3 nM in the PC3 cell line. Abiraterone has a GI50 in this line of 4820 nM. By contrast SOP1812 has a GI50 of 247 nM in the LNCaP line, which is also derived from a patient with metastatic prostate cancer but is androgen positive. The PC3 line is derived from a metastatic carcinoma following androgen suppression therapy and is thus androgen independent and is a model for castration-resistant prostate cancer when hormone therapies are no longer effective. We have evaluated the activity of SOP1812 in the PC3 xenograft model using a twice-weekly 1 mg/kg dose regimen IV administered, against a saline control and abiraterone, at a daily dose of 200 mg/kg, administered by the PO route, both over a 28-day period. No weight loss was observed in treated animals with either drug. SOP1812 produced statistically significant tumor shrinkage (P value of 0.0008) relative to the controls, with a T/C value of 33.5% on day 28. Abiraterone treatment resulted in a T/C value of 61.6%, with a P value of 0.0382. SOP1812 is bio-available at therapeutic doses and is well tolerated at these levels in this animal model. It is currently being evaluated as a candidate for clinical development by Qualigen Therapeutics Inc. Citation Format: Nicole Williams, Jenny Worthington, Stephen Neidle, Ahmed Ahmed. The potent quadruplex-binding compound SOP1812 shows potent anti-proliferative activity in a prostate cancer cell panel and anti-tumor activity in an in vivo model of metastatic prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4068.