Phosphoflow cytometry to assess cytokine signaling pathways in peripheral immune cells: potential for inferring immune cell function and treatment response in patients with solid tumors

Abstract Tumor biopsy is often not available or difficult to obtain in patients with solid tumors. Investigation of the peripheral immune system allows for in-depth and dynamic profiling of patient immune response prior to and over the course of treatment and disease. Phosphoflow cytometry is a flow cytometry‒based method to detect levels of phosphorylated proteins in single cells. This method can be applied to peripheral immune cells to determine responsiveness of signaling pathways in specific immune subsets to cytokine stimulation, improving on simply defining numbers of populations of cells based on cell surface markers. Here, we review studies using phosphoflow cytometry to (a) investigate signaling pathways in cancer patients’ peripheral immune cells compared with healthy donors, (b) compare immune cell function in peripheral immune cells with the tumor microenvironment, (c) determine the effects of agents on the immune system, and (d) predict cancer patient response to treatment and outcome. In addition, we explore the use and potential of phosphoflow cytometry in preclinical cancer models. We believe this review is the first to provide a comprehensive summary of how phosphoflow cytometry can be applied in the field of cancer immunology, and demonstrates that this approach holds promise in exploring the mechanisms of response or resistance to immunotherapy both prior to and during the course of treatment. Additionally, it can help identify potential therapeutic avenues that can restore normal immune cell function and improve cancer patient outcome

Microwave Synthesis of Quaternary Ammonium Salts

The microwave synthesis of several quaternary ammonium salts is described. The synthesis provides comparable or better yields than published methods with reduced reaction times and in the absence of solvent

Metformin for biochemical recurrence of prostate cancer: Immune data from a phase 2 study

377 Background: Metformin impacts immune response in several ways. It protects CD8 TILs from apoptotic death, downregulates CD39 and CD73, reduces MDSC activity and suppresses the transcription of PD1 thus enhancing CD8+ T cell antitumor activity (Ma et al, 2000, Nature). There is limited data on the immunologic impact of metformin treatment in hormone sensitive prostate cancer. Methods: We conducted an open label, randomized, phase II trial of bicalutamide with or without metformin of patients with high risk, biochemically recurrent prostate cancer (NCT02614859). Patients were randomized 1:2 to observation for an initial 8 weeks or metformin 1000 mg twice daily. Bicalutamide 50 mg/day was added after 8 weeks to both arms. The study discontinued accrual after interim analysis indicated no difference in PSA at 32 weeks between the two arms; however, metformin monotherapy for 8 weeks induced modest PSA declines observed in 40% of patients. Here we report immune responses in a subgroup of patients (N=12), including systemic cytokine levels and 158 circulating immune cell subsets after 8 weeks of metformin monotherapy. Results: Twelve patients treated at the NCI were analyzed. After 8 weeks, the metformin arm showed increased pDCs and lower Tregs compared to baseline. Significant differences in the percent change of immune parameters after 8 weeks of metformin monotherapy compared to 8 weeks of observation are summarized. Conclusions: Metformin has been shown to reduce markers of immune exhaustion in hormone sensitive prostate cancer which is supported by a greater reduction of PD-1 + and Tim3 + NK cells. Additional immune changes included increases in activated subpopulations of natural killer (NK) cells, which have been reported as a potential predictive biomarker of prolonged treatment response to hormone therapy in prostate cancer (Pasero et al, Oncotarget, 2015). Clinical trial information: NCT02614859 . [Table: see text

Multiplatform molecular test performance in indeterminate thyroid nodules

BackgroundApproximately 25% of thyroid nodule fine‐needle aspirates (FNAs) have cytology that is indeterminate for malignant disease. Accurate risk stratification of these FNAs with ancillary testing would reduce unnecessary thyroid surgery.MethodsWe evaluated the performance of an ancillary multiplatform test (MPTX) that has three diagnostic categories (negative, moderate, and positive). MPTX includes the combination of a mutation panel (ThyGeNEXT®) and a microRNA risk classifier (ThyraMIR®). A blinded, multicenter study was performed using consensus histopathology diagnosis among three pathologists to validate test performance.ResultsUnanimous consensus diagnosis was reached in 197 subjects with indeterminate thyroid nodules; 36% had disease. MPTX had 95% sensitivity (95% CI,86%‐99%) and 90% specificity (95% CI,84%‐95%) for disease in prevalence adjusted nodules with Bethesda III and IV cytology. Negative MPTX results ruledout disease with 97% negative predictive value (NPV; 95% CI,91%‐99%) at a 30% disease prevalence, while positive MPTX results ruledin high risk disease with 75% positive predictive value (PPV; 95% CI,60%‐86%). Such results are expected in four out of five Bethesda III and IV nodules tested, including RAS positive nodules in which the microRNA classifier was useful in rulingin disease. 90% of mutation panel false positives were due to analytically verified RAS mutations detected in benign adenomas. Moderate MPTX results had a moderate rate of disease (39%, 95% CI,23%‐54%), primarily due to RAS mutations, wherein the possibility of disease could not be excluded.ConclusionsOur results emphasize that decisions for surgery should not solely be based on RAS or RAS‐like mutations. MPTX informs management decisions while accounting for these challenges.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/163550/2/dc24564_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/163550/1/dc24564.pd

A randomized phase 2 study of bicalutamide with or without metformin for biochemical recurrence in overweight or obese prostate cancer patients (BIMET-1)

Background Metformin may have anticancer effects that are independent of its hypoglycemic effects. Retrospective studies have shown that metformin use is associated with decreased incidence of prostate cancer and prostate cancer-specific mortality. Preclinical studies suggesting additive anticancer effects of combining metformin and bicalutamide prompted this clinical trial (NCT02614859). Methods This open-label, randomized, phase 2 trial enrolled non-diabetic patients with biochemically recurrent prostate cancer, a PSADT of 3-9 months, BMI > 25 and normal testosterone. Patients were randomized 1:2 to observation for an initial 8 weeks (Arm A) or metformin 1000 mg twice daily (Arm B). Bicalutamide 50 mg/day was added after 8 weeks to both arms. The primary objective was to evaluate the number of patients with undetectable PSA ( < 0.2 ng/mL) at the end of 32 weeks. Immune correlatives were assessed as exploratory endpoints. Results A total of 29 patients were enrolled from March 2015 to January 2020. No difference was seen between the 2 arms in the proportion of patients with undetectable PSA. Modest PSA decrease ranging from 4% to 24% were seen in 40.0% (95% CI: 19.1-64.0%) of patients with metformin monotherapy, compared to 11.1% (95% CI: 0.3-48.3%) in the observation arm. Metformin monotherapy reduced PD-1(+) NK cells, and increased NKG2D(+) NK cells. The combination of metformin and bicalutamide led to greater reductions in PD-1 expressing NK, CD4(+) T, and CD8(+) T-cell subsets compared to bicalutamide alone. The trial was stopped early due to predicted inability to achieve its primary endpoint. Conclusions Although metformin plus bicalutamide was well tolerated, there was no improvement in rates of achieving undetectable PSA at 32 weeks. Metformin monotherapy induced modest PSA declines in 40% of patients after 8 weeks. Metformin, given alone and in combination with bicalutamide, displayed immune modifying effects, primarily within NK and T cells subsets

A Phase I Single-Arm Study of Biweekly NHS-IL12 in Patients With Metastatic Solid Tumors

NHS-IL12 is a first-in-class, recombinant fusion protein composed of the human monoclonal antibody NHS76 (binds exposed DNA/histones at sites of intratumoral necrosis) fused to 2 IL-12 heterodimers. The maximum tolerated dose (MTD) and recommended phase II dose (RP2D) of NHS-IL12 monotherapy given subcutaneously (SC) every 4 weeks was previously reported. The study was expanded to include a high-exposure cohort with NHS-IL12 SC every 2 weeks (q2w). This single-arm, phase I trial evaluated NHS-IL12 12 µg/kg SC q2w or 16.8µg/kg SC q2w in patients with metastatic solid tumors. The primary endpoint was safety. Using a 3+3 design, 13 patients with advanced cancer were enrolled and 12 were dose-limiting toxicity (DLT) evaluable. There was 1 DLT (Grade 3 aspartate transaminase/alanine transaminase [AST/ALT] elevation). Other grade 3 toxicities included: flu-like symptoms 1/13 (8%), decreased absolute lymphocyte count (ALC) 1/13 (8%), decreased white blood cell count (WBC) 1/13 (8%), but most adverse events reported were low grade and self-limiting grade. Fifty percent of evaluable patients (6/12) experienced stable disease (SD) with 42% (5/12) developing progressive disease (PD) at the first restaging. Biweekly NHS-IL12 was well tolerated in this small phase I study. Additional studies incorporating NHS-IL12 with other immunomodulating agents are underway. (ClinicalTrials.gov Identifier: NCT01417546)