A Strong B-cell Response Is Part of the Immune Landscape in Human High-Grade Serous Ovarian Metastases.

PURPOSE: In high-grade serous ovarian cancer (HGSOC), higher densities of both B cells and the CD8+ T-cell infiltrate were associated with a better prognosis. However, the precise role of B cells in the antitumor response remains unknown. As peritoneal metastases are often responsible for relapse, our aim was to characterize the role of B cells in the antitumor immune response in HGSOC metastases. EXPERIMENTAL DESIGN: Unmatched pre and post-chemotherapy HGSOC metastases were studied. B-cell localization was assessed by immunostaining. Their cytokines and chemokines were measured by a multiplex assay, and their phenotype was assessed by flow cytometry. Further in vitro and in vivo assays highlighted the role of B cells and plasma cell IgGs in the development of cytotoxic responses and dendritic cell activation. RESULTS: B cells mainly infiltrated lymphoid structures in the stroma of HGSOC metastases. There was a strong B-cell memory response directed at a restricted repertoire of antigens and production of tumor-specific IgGs by plasma cells. These responses were enhanced by chemotherapy. Interestingly, transcript levels of CD20 correlated with markers of immune cytolytic responses and immune complexes with tumor-derived IgGs stimulated the expression of the costimulatory molecule CD86 on antigen-presenting cells. A positive role for B cells in the antitumor response was also supported by B-cell depletion in a syngeneic mouse model of peritoneal metastasis. CONCLUSIONS: Our data showed that B cells infiltrating HGSOC omental metastases support the development of an antitumor response. Clin Cancer Res; 23(1); 250-62. ©2016 AACR.

Neoadjuvant Chemotherapy Modulates the Immune Microenvironment in Metastases of Tubo-Ovarian High-Grade Serous Carcinoma.

PURPOSE: The purpose of this study was to assess the effect of neoadjuvant chemotherapy (NACT) on immune activation in stage IIIC/IV tubo-ovarian high-grade serous carcinoma (HGSC), and its relationship to treatment response. EXPERIMENTAL DESIGN: We obtained pre- and posttreatment omental biopsies and blood samples from a total of 54 patients undergoing platinum-based NACT and 6 patients undergoing primary debulking surgery. We measured T-cell density and phenotype, immune activation, and markers of cancer-related inflammation using IHC, flow cytometry, electrochemiluminescence assays, and RNA sequencing and related our findings to the histopathologic treatment response. RESULTS: There was evidence of T-cell activation in omental biopsies after NACT: CD4(+) T cells showed enhanced IFNγ production and antitumor Th1 gene signatures were increased. T-cell activation was more pronounced with good response to NACT. The CD8(+) T-cell and CD45RO(+) memory cell density in the tumor microenvironment was unchanged after NACT but biopsies showing a good therapeutic response had significantly fewer FoxP3(+) T regulatory (Treg) cells. This finding was supported by a reduction in a Treg cell gene signature in post- versus pre-NACT samples that was more pronounced in good responders. Plasma levels of proinflammatory cytokines decreased in all patients after NACT. However, a high proportion of T cells in biopsies expressed immune checkpoint molecules PD-1 and CTLA4, and PD-L1 levels were significantly increased after NACT. CONCLUSIONS: NACT may enhance host immune response but this effect is tempered by high/increased levels of PD-1, CTLA4, and PD-L1. Sequential chemoimmunotherapy may improve disease control in advanced HGSC. Clin Cancer Res; 22(12); 3025-36. ©2016 AACR.

Noninvasive urinary miRNA biomarkers for early detection of pancreatic adenocarcinoma.

Currently, the majority of patients diagnosed with pancreatic ductal adenocarcinoma (PDAC) present with locally invasive and/or metastatic disease, resulting in five-year survival of less than 5%. The development of an early diagnostic test is, therefore, expected to significantly impact the patient's prognosis. In this study, we successfully evaluated the feasibility of identifying diagnostic cell free microRNAs (miRNAs) for early stage PDAC, through the analysis of urine samples. Using Affymetrix microarrays, we established a global miRNA profile of 13 PDAC, six chronic pancreatitis (CP), and seven healthy (H) urine specimens. Selected differentially expressed miRNAs were subsequently investigated using an independent technique (RT-PCR) on 101 urine samples including 46 PDAC, 29 CP and 26 H. Receiver operating characteristic (ROC) and logistic regression analyses were applied to determine the discriminatory potential of the candidate miRNA biomarkers. Three miRNAs (miR-143, miR-223, and miR-30e) were significantly over-expressed in patients with Stage I cancer when compared with age-matched healthy individuals (P=0.022, 0.035 and 0.04, respectively); miR-143, miR-223 and miR-204 were also shown to be expressed at higher levels in Stage I compared to Stages II-IV PDAC (P=0.025, 0.013 and 0.008, respectively). Furthermore, miR-223 and miR-204 were able to distinguish patients with early stage cancer from patients with CP (P=0.037 and 0.036). Among the three biomarkers, miR-143 was best able to differentiate Stage I (n=6) from healthy (n=26) with area under the curve (AUC) of 0.862 (95% CI 0.695-1.000), with sensitivity (SN) of 83.3% (95% CI 50.0-100.0), and specificity (SP) of 88.5% (95% CI 73.1-100.0). The combination of miR-143 with miR-30e was significantly better at discriminating between these two groups, achieving an AUC of 0.923 (95% CI 0.793-1.000), with SN of 83.3% (95% CI 50.0-100.0) and SP of 96.2% (95% CI 88.5-100.0). In this feasibility study, we demonstrate for the first time the utility of miRNA biomarkers for non-invasive, early detection of PDAC in urine specimens.

Chemotherapy Response Score: Development and Validation of a System to Quantify Histopathologic Response to Neoadjuvant Chemotherapy in Tubo-Ovarian High-Grade Serous Carcinoma.

PURPOSE: To develop and validate a histopathologic scoring system for measuring response to neoadjuvant chemotherapy in interval debulking surgery specimens of stage IIIC to IV tubo-ovarian high-grade serous carcinoma. PATIENTS AND METHODS: A six-tier histopathologic scoring system was proposed and applied to a test cohort (TC) of 62 patients treated with neoadjuvant chemotherapy and interval debulking surgery. Adnexal and omental sections were independently scored by three pathologists. On the basis of TC results, a three-tier chemotherapy response score (CRS) system was developed and applied to an independent validation cohort of 71 patients. RESULTS: The initial system showed moderate interobserver reproducibility and prognostic stratification of TC patients when applied to the omentum but not to the adnexa. Condensed to a three-tier score, the system was highly reproducible (kappa, 0.75). When adjusted for age, stage, and debulking status, the score predicted progression-free survival (PFS; score 2 v 3; median PFS, 11.3 v 32.1 months; adjusted hazard ratio, 6.13; 95% CI, 2.13 to 17.68; P < .001). The three-tier CRS system applied to omental samples from the validation cohort showed high reproducibility (kappa, 0.67) and predicted PFS (CRS 1 and 2 v 3: median, 12 v 18 months; adjusted hazard ratio, 3.60; 95% CI, 1.69 to 7.66; P < .001). CRS 3 also predicted sensitivity to first-line platinum therapy (94.3% negative predictive value for progression < 6 months). A Web site was established to train pathologists to use the CRS system. CONCLUSION: The CRS system is reproducible and shows prognostic significance for high-grade serous carcinoma. Implementation in international pathology reporting has been proposed by the International Collaboration on Cancer Reporting, and the system could potentially have an impact on patient care and research.