Abstract 408: Reduction of tumor-infiltrating B cells linked to recurrence of NSCLC tumors
Authors: Juncker-Jensen Anna , Stavrou Nicholas , Nagy Mate , Parnell Erinn , Kuo Judy , Leones Eric , Pham Kathy , Sahafi Flora 
Published: September 2020

Abstract
Introduction: Lung cancer is the leading cause of cancer related mortality worldwide. Non-small cell lung cancer (NSCLC), accounting for approximately 80-85% of all lung cancer cases, is characterized by a poor response to chemotherapy and a low survival rate. Early stage NSCLC patients are typically treated with complete surgical resection of the tumor, but nevertheless 30-50% of these patients end up developing recurrence within 5 years of surgery. While the presence of tumor-infiltrating lymphocytes (TILs) has been shown to be significantly correlated with a positive clinical prognosis in multiple types of cancer the role of tumor-infiltrating B cells (TIBs) remains more controversial.
Experimental Procedures: To perform a comprehensive immunoprofiling of NSCLC FFPE tumor samples we used MultiOmyx™, a proprietary immunofluorescent multiplexing assay. Using a 15-marker panel we have analyzed the proportion of T cell subtypes, B cells, Granulocytes, M1/M2-type tumor-associated macrophages, as well as the expression of PD-1, PD-L1, LAG-3, TIM-3, ICOS, and OX40 in 12 samples from patients with early stage (stage I-II) NSCLC (6 non-recurrent and 6 recurrent).
Results: Using the MultiOmyx image analysis suite based on NeoGenomics' proprietary deep-learning algorithms, we compared the number and overall density of immune cell populations between non-recurrent and recurrent NSCLC samples and found recurrent samples to have a highly significant decrease in B cells (166.8 cells/mm2 to 26.2 cells/mm2; p-value 0.006). In addition to a decrease in the overall density of B cells, we also observed a decrease in the tumor-infiltration rate, measured as the % of cells found inside the tumor area versus in the stroma of the tumor samples. This demonstrates that not only are there fewer B cells in the recurrent samples, but the B cells present are also less likely to infiltrate into the tumor area. While research on tumor immunity has been highly focused on T cells, the specific role of B cells in this area has been somewhat overlooked. While the release of antibodies and interleukin-10 might be involved in TIB-mediated tumor immunity, interactions between TIBs and TILs as well as the PD-1/PD-L1 cascade has been documented more recently. Indeed, in our study we did observe a significant positive correlation between the densities of B cells and cytotoxic lymphocytes, as well as B cells and PD-L1, although interestingly this was only observed in the recurrent group of patients. We are currently in the process of performing further multiplexing analyses on these samples to examine the mechanism behind these correlations and their potential significance for NSCLC recurrence.
Conclusion: Identifying early stage NSCLC patients at high risk of recurrence following surgical resection can help guide a more accurate patient selection and treatment plan for this group. We present data to suggest that B-cell density and tumor-infiltration rate represents novel biomarkers for NSCLC patients at risk for recurrence.
Citation Format: Anna Juncker-Jensen, Nicholas Stavrou, Mate Nagy, Erinn Parnell, Judy Kuo, Eric Leones, Kathy Pham, Flora Sahafi. Reduction of tumor-infiltrating B cells linked to recurrence of NSCLC tumors [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 408.