Lessons learned from clinical trial queries on small biopsy collections: importance of rapid on-site evaluation.

INTRODUCTION: Small biopsies and cytology specimens have become increasingly important for clinical trials and biomarker testing. Thus, institutions must ensure that adequate lesional material meeting the specifications for a multitude of different protocols is available. This can be achieved using rapid on-site evaluation (ROSE). The aim of the present study was to determine the recent clinical trial biopsy characteristics and study the feedback on these collections at our institution. MATERIALS AND METHODS: Clinical trial biopsies performed at our institution and trial feedback (including "queries") were analyzed from the 2017 to 2019. The query data were reviewed in detail, in addition to any protocol modifications related to biopsy requirements and study protocol changes. RESULTS: A total of 698 biopsy collections were performed for clinical trial purposes for 95 trials, with most requiring biopsies at >1 time point (63.2%), for phase I or II trials (92.6%), and for specific tumor types (67.4%). Only 18 of the trials (18.9%) requiring fresh tissue biopsies provided feedback. The feedback included data from 90 cases (12.9%), of which 27 (30.0%) had queries regarding insufficient (n = 10; 37.0%) or borderline (n = 17; 63.0%) tumor tissue. Only 1 (3.7%) of these had had ROSE by cytology. ROSE was performed in accordance with institutional guidelines (45.3%), as required by the study (1.1%), or because of trial modification (5.3%). CONCLUSIONS: The present investigation has shown the high volume of clinical trial biopsies managed at our academic cancer center. Feedback from the trials was low at 18.9% and frequently involved suboptimal cases without ROSE used at acquisition. This has led to more widespread adoption of ROSE to mitigate insufficient biopsy specimens and repeat procedures. The high volume of clinical trial biopsies and variability in trial needs necessitates a collaborative multidisciplinary network, including cytology services, to facilitate these important biopsies for patients with cancer.

Helicase-Driven Activation of NFκB-COX2 Pathway Mediates the Immunosuppressive Component of dsRNA-Driven Inflammation in the Human Tumor Microenvironment.

Presence of cytotoxic CD8+ T cells (CTL) in tumor microenvironments (TME) is critical for the effectiveness of immune therapies and patients' outcome, whereas regulatory T(reg) cells promote cancer progression. Immune adjuvants, including double-stranded (ds)RNAs, which signal via Toll-like receptor-3 (TLR3) and helicase (RIG-I/MDA5) pathways, all induce intratumoral production of CTL-attractants, but also Treg attractants and suppressive factors, raising the question of whether induction of these opposing groups of immune mediators can be separated. Here, we use human tumor explant cultures and cell culture models to show that the (ds) RNA Sendai Virus (SeV), poly-I:C, and rintatolimod (poly-I:C12U) all activate the TLR3 pathway involving TRAF3 and IRF3, and induce IFNα, ISG-60, and CXCL10 to promote CTL chemotaxis to ex vivo-treated tumors. However, in contrast with SeV and poly I:C, rintatolimod did not activate the MAVS/helicase pathway, thus avoiding NFκB- and TNFα-dependent induction of COX2, COX2/PGE2-dependent induction of IDO, IL10, CCL22, and CXCL12, and eliminating Treg attraction. Induction of CTL-attractants by either poly I:C or rintatolimod was further enhanced by exogenous IFNα (enhancer of TLR3 expression), whereas COX2 inhibition enhanced the response to poly-I:C only. Our data identify the helicase/NFκB/TNFα/COX2 axis as the key suppressive pathway of dsRNA signaling in human TME and suggest that selective targeting of TLR3 or elimination of NFκB/TNFα/COX2-driven suppression may allow for selective enhancement of type-1 immunity.Significance: This study characterizes two different poly-I:C-induced signaling pathways in their induction of immunostimulatory and suppressive factors and suggests improved ways to reprogram the TME to enhance the antitumor efficacy of immunotherapies. Cancer Res; 78(15); 4292-302. ©2018 AACR.