Stanley Lipkowitz

Targeting metabolic vulnerability by combining NAMPT inhibitors and disulfiram for treatment of recurrent ovarian cancer

Abstract Ovarian cancer (OV) has the highest mortality rate among gynecological cancers. As OV progresses, tumor cells spread outside the ovaries to the peritoneal and abdominal cavities, forming cell clusters that float in the ascitic fluid caused by peritonitis carcinomatosa, leading to further dissemination and metastasis. These cell clusters are enriched with cancer stem cells (CSCs) which are responsible for treatment resistance, recurrence, and metastasis. Therefore, targeting CSCs is a potentially effective approach for treating OV. However, understanding how CSCs acquire treatment resistance and identifying targets against CSCs remains challenging. In this study, we demonstrate that 3D-spheroids of OV cell lines exhibit higher stemness than conventional adherent cells. Metabolomics profiling studies have revealed that 3D-spheroids maintain a high-energy state through increased glucose utilization in the citric acid cycle (TCA), efficient nucleotide phosphorylation, and elevated phosphocreatine as an energy buffer. We also found that nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme for NAD + production, is highly expressed in OV. Furthermore, the approach based on NAMPT dependence rather than histology found NAMPT to be a potential therapeutic target against CSCs, while also serving as a prognostic indicator in OV. Moreover, we identified a previously unrecognized anti-tumor mechanism whereby disulfiram, an aldehyde dehydrogenase (ALDH) inhibitor, synergistically inhibited mitochondrial function when combined with NAMPT inhibitors - leading to cell cycle arrest in G2/M. Finally, the combination of a NAMPT inhibitor and disulfiram showed significant anti-tumor effects and extended survival in an animal model. Our findings demonstrate the potential of spheroids as a preclinical model for targeting OV CSCs and also indicate that the combination of NAMPT inhibitors and disulfiram is a promising therapeutic strategy to overcome recurrent OV.

A Single-Arm, Open-Label Phase II Study of ONC201 in Recurrent/Refractory Metastatic Breast Cancer and Advanced Endometrial Carcinoma

Abstract Background ONC201 is a small molecule that can cause nonapoptotic cell death through loss of mitochondrial function. Results from the phase I/II trials of ONC201 in patients with refractory solid tumors demonstrated tumor responses and prolonged stable disease in some patients. Methods This single-arm, open-label, phase II clinical trial evaluated the efficacy of ONC201 at the recommended phase II dose (RP2D) in patients with recurrent or refractory metastatic breast or endometrial cancer. Fresh tissue biopsies and blood were collected at baseline and at cycle 2 day 2 for correlative studies. Results Twenty-two patients were enrolled; 10 patients with endometrial cancer, 7 patients with hormone receptor–positive breast cancer, and 5 patients with triple-negative breast cancer. The overall response rate was 0%, and the clinical benefit rate, defined by complete response (CR) + partial response (PR) + stable disease (SD), was 27% (n = 3/11). All patients experienced an adverse event (AE), which was primarily low grade. Grade 3 AEs occurred in 4 patients; no grade 4 AEs occurred. Tumor biopsies did not show that ONC201 consistently induced mitochondrial damage or alterations in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) or the TRAIL death receptors. ONC201 treatment caused alterations in peripheral immune cell subsets. Conclusion ONC201 monotherapy did not induce objective responses in recurrent or refractory metastatic breast or endometrial cancer at the RP2D dose of 625 mg weekly but had an acceptable safety profile (ClinicalTrials.gov Identifier: NCT03394027).

ONC201 in Recurrent/Refractory Metastatic Breast Cancer and Advanced Endometrial Carcinoma

Background: The new drug ONC201 have been shown to kill breast cancer and endometrial cancer cells in the laboratory. The exact mechanism of action is not completely clear yet, but the ONC201 destroys the mitochondria inside the cells. Blocking mitochondrial activity may kill tumor cells, which would shrink tumors. Researchers want to see if ONC201 helps shrink tumors of certain breast or endometrial cancers and if that effect is maintained. Objective: To see if ONC201 shrinks tumors with a lasting effect. Eligibility: Adults ages 18 and older who have metastatic breast cancer (hormone-positive or triple-negative) or metastatic endometrial cancers. Design: Participants will be screened with: * Medical history * Physical exam * Heart, blood, and urine tests * Computed tomography (CT) and bone scans * Review of medical report and tumor sample * Participants will have a tumor biopsy before starting treatment and after 5 weeks taking the study drug. A scan or ultrasound may be used to guide the biopsy. Patients will receive local anesthetic and a needle will remove a small piece of tumor. * The study will be done in 28-day cycles. Every day 1 of each cycle participants will repeat most screening tests, will be seen by the physician and receive a supply of the study drug. * Participants will take the study drug by mouth once every 7 days. They will keep a diary of when they take the drug and any side effects. During cycle 1, participants will get weekly calls to discuss their health and symptoms. Images will be repeated every 2 cycles to evaluate response to the treatment.