Thanh H. Dellinger

Immunologic Signatures of Peripheral Blood T Cells Reveal the Outcome of p53MVA Vaccine and Pembrolizumab Treatment in Patients with Advanced Ovarian Cancer

Abstract Purpose: Our previous studies indicated that p53-reactive T cells were associated with clinical benefit in patients with advanced ovarian cancer who were treated with p53-expressing modified vaccinia Ankara (p53MVA) vaccine and gemcitabine chemotherapy. To replace chemotherapy with an approach that will enhance vaccine efficacy and antitumor immunity, we treated patients with p53MVA in combination with PD-1 checkpoint blocker, pembrolizumab. We also attempted to further characterize the activation status of T cells prior to vaccination and during treatment. Experimental Design: Patients received up to three triweekly vaccinations concurrent with pembrolizumab, followed by pembrolizumab monotherapy at 3-week intervals. Correlative studies analyzed peripheral blood T-cell phenotypes and profiles of immune function gene expression. Results: We observed 6/28 (21%) patients with a clinical benefit to therapy, including 3 partial responses (PR) and 3 patients with stable disease (SD) for 6+ months. The median progression-free survival was 1.8 months (95% confidence interval: 1.7–3.8) and median overall survival was 15.1 months (9.4–30.4). Two patients remain progression-free at 28 and 33 months. Of the 18 patients evaluable in correlative studies, 6 were immunologic responders of whom 5 had clinical benefit (3 PR, 2 SD). Immunologic non-responders expressed in pretreatment peripheral blood mononuclear cell samples high levels of mRNA for multiple molecules associated with terminally differentiated T cells. Conclusions: p53MVA/pembrolizumab immunotherapy showed promising antitumor activity in patients who demonstrated functionally competent peripheral blood T cells. Detection of markers of terminally differentiated T cells before treatment may identify patients unlikely to respond to p53MVA/pembrolizumab. Significance: The activity of a combination immunotherapy of p53 vaccine and PD-1 checkpoint blockade in patients with platinum-resistant ovarian cancer was evaluated in a phase II trial. Clinical benefit was correlated with the responsive immune status of patients before and during the treatment, defining potential predictive markers for immune therapy.

Specific targeting of ovarian tumor-associated macrophages by large, anionic nanoparticles

Significance Tumor-associated macrophages (TAMs) are abundant in tumor microenvironments and are predominantly immunosuppressive. The ratio between immunosuppressive M2 TAMs and proinflammatory M1 TAMs correlates with worse outcomes for many cancers, including ovarian cancer. TAMs are potential targets for immunotherapy, and here we show that, when relatively large (>100-nm) anionic nanoparticles are administered intraperitoneally (i.p.), they selectively accumulate in TAMs with high efficiency (>60% of injected dose). The composition of particles that achieve this targeting appears to be quite flexible. Thus, based on our results, many formulations can now be tested for targeted immunotherapy of ovarian cancer and other cancers of the i.p. cavity.

Hyperthermic Intraperitoneal Chemotherapy–Induced Molecular Changes in Humans Validate Preclinical Data in Ovarian Cancer

PURPOSE Hyperthermic intraperitoneal chemotherapy (HIPEC) confers a survival benefit in epithelial ovarian cancer (EOC) and in preclinical models. However, the molecular changes induced by HIPEC have not been corroborated in humans. PATIENTS AND METHODS A feasibility trial evaluated clinical and safety outcomes of HIPEC with cisplatin during optimal cytoreductive surgery (CRS) in patients with EOC diagnosed with stage III, IV, or recurrent EOC. Pre- and post-HIPEC biopsies were comprehensively profiled with genomic and transcriptomic sequencing to identify mutational and RNAseq signatures correlating with response; the tumor microenvironment was profiled to identify potential immune biomarkers; and transcriptional signatures of tumors and normal samples before and after HIPEC were compared to investigate HIPEC-induced acute transcriptional changes. RESULTS Thirty-five patients had HIPEC at the time of optimal CRS; all patients had optimal CRS. The median progression-free survival (PFS) was 24.7 months for primary patients and 22.4 for recurrent patients. There were no grade 4 or 5 adverse events. Anemia was the most common grade 3 adverse event (43%). Hierarchical cluster analyses identified distinct transcriptomic signatures of good versus poor responders to HIPEC correlating with a PFS of 29.9 versus 7.3 months, respectively. Among good responders, significant HIPEC-induced molecular changes included immune pathway upregulation and DNA repair pathway downregulation. Within cancer islands, % programmed cell death protein 1 expression in CD8+ T cells significantly increased after HIPEC. An exceptional responder (PFS 58 months) demonstrated the highest programmed cell death protein 1 increase. Heat shock proteins comprised the top differentially upregulated genes in HIPEC-treated tumors. CONCLUSION Distinct transcriptomic signatures identify responders to HIPEC, and preclinical model findings are confirmed for the first time in a human cohort.

Surgery and Chemotherapy With or Without Chemotherapy After Surgery in Treating Patients With Ovarian, Fallopian Tube, Uterine, or Peritoneal Cancer

This phase I trial studies the side effects and how well surgery and heated chemotherapy with or without non-heated chemotherapy after surgery works in treating patients with ovarian, fallopian tube, uterine, or peritoneal cancer. Giving a dose of heated chemotherapy into the abdomen during surgery that is done to remove ovarian, fallopian tube, uterine, or peritoneal cancer may help lower the risk of the cancer coming back. Giving unheated chemotherapy drugs directly into the abdomen after surgery may kill more tumor cells.