Abstract 1722: Role of tumor infiltrating lymphocytes and spatial immune heterogeneity in sensitivity to PD-1 axis blockers in non-small cell lung cancer (NSCLC)

The rapid clinical expansion of immune checkpoint blockers (ICB) has transformed the therapeutic arsenal for non-small cell lung cancer (NSCLC). However, only a relatively small fraction of patients benefits from these treatments and those who respond can develop acquired resistance. This underlines the need to identify factors or biomarkers associated with treatment sensitivity and resistance to guide clinical decisions. It has been proposed that elevated levels of tumor infiltrating lymphocytes (TIL) in the tumor microenvironment could be associated with favorable clinical outcomes after treatment with ICB. However, few studies have explored this relationship and they used semi-quantitative scoring methods and/or analyzed small tumor areas. Here, we used multiplexed quantitative immunofluorescence (QIF) panels to study major TIL subsets (DAPI, CK, CD4, CD8 and CD20) and T-cell exhaustion markers (DAPI, CD3, LAG-3, PD-1, TIM-3) in full-face baseline whole-tumor slides from a large multi-institutional patient cohort (n=179). The analysis of numerous fields of view per case allowed us to examine the spatial distribution of immune cells and spatial immune heterogeneity. Our results demonstrate that CD8+ effector T-cells are the largest TIL subpopulation and that they are preferentially located in the stromal compartment. We also show that tertiary lymphoid structures have limited association with survival and their detection depends on the size of the tissue area analyzed. Additionally, higher levels of baseline CD8+ T-cells in the stroma were significantly associated with better survival in PD-L1 positive patients but not in PD-L1 negative. To validate these results, we used whole-exome sequencing to analyze the TCR-burden in an independent cohort of ICI-treated NSCLC patients. Increased expression of the exhaustion markers LAG-3 and TIM-3 in CD3 positive T-cells was associated with reduced survival. Finally, we used a novel multiparametric heterogeneity metric termed Rao’s quadratic entropy that enabled us to measure the spatial immune heterogeneity and was associated with worse survival. In summary, we quantitatively measured the density, functional properties, and spatial distribution of major TIL subsets in a large cohort of NSCLC patients treated with ICB. Our results highlight the prominent role of TILs in NSCLC and their potential role as a biomarker. These results could be easily translated into the clinic and used to guide optimal treatment options.

Citation Format: Miguel Lopez de Rodas Gregorio, Venkata Nagineni, Arvind Ravi, Ila J. Datar, Mari Mino-Kenudson, German Corredor, Cristian Barrera, Lindsey Behlman, David L. Rimm, Roy S. Herbst, Anant Madabhushi, Jonathan W. Riess, Vamsidhar Velcheti, Matthew Hellmann, Justin F. Gainor, Kurt A. Schalper. Role of tumor infiltrating lymphocytes and spatial immune heterogeneity in sensitivity to PD-1 axis blockers in non-small cell lung cancer (NSCLC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1722.

Role of tumor infiltrating lymphocytes and spatial immune heterogeneity in sensitivity to PD-1 axis blockers in non-small cell lung cancer

BACKGROUND

Tumor infiltrating lymphocytes (TILs) reflect adaptive antitumor immune responses in cancer and are generally associated with favorable prognosis. However, the relationships between TILs subsets and their spatial arrangement with clinical benefit from immune checkpoint inhibitors (ICI) in non-small cell lung cancer (NSCLC) remains less explored.

METHODS

We used multiplexed quantitative immunofluorescence panels to determine the association of major TILs subpopulations, CD8+ cytotoxic T cells, CD4+ helper T cells and CD20+ B cells, and T cell exhaustion markers, programmed cell death protein-1 (PD-1),lymphocyte-activation gene 3 (LAG-3) and T cell immunoglobulin mucin-3 (TIM-3) with outcomes in a multi-institutional cohort of baseline tumor samples from 179 patients with NSCLC treated with ICI. The analysis of full-face tumor biopsies including numerous fields of view allowed a detailed spatial analysis and assessment of tumor immune heterogeneity using a multiparametric quadratic entropy metric (Rao's Q Index (RQI)).

RESULTS

TILs were preferentially located in the stromal tissue areas surrounding tumor-cell nests and CD8+ T cells were the most abundant subset. Higher density of stromal CD8+ cytotoxic T cells was significantly associated with longer survival, and this effect was more prominent in programmed death ligand-1 (PD-L1) positive cases. The role of baseline T cell infiltration to stratify PD-L1 expressing cases was confirmed measuring the T cell receptor-burden in an independent NSCLC cohort studied with whole-exome DNA sequencing. High levels of LAG-3 on T cells or elevated RQI heterogeneity index were associated with worse survival in the cohort.

CONCLUSION

Baseline T cell density and T cell exhaustion marker expression can stratify outcomes in PD-L1 positive patients with NSCLC treated with ICI. Spatial immune heterogeneity can be measured using the RQI and is associated with survival in NSCLC.

Spatial Analysis and Clinical Significance of HLA Class-I and Class-II Subunit Expression in Non-Small Cell Lung Cancer

PURPOSE

To analyze the distribution, associated immune contexture, and clinical significance of human leukocyte antigen (HLA) class-I and HLA class-II subunits in non-small cell lung cancer (NSCLC).

EXPERIMENTAL DESIGN

Using spatially resolved and quantitative multiplexed immunofluorescence we studied the tumor/stromal tissue distribution, cancer cell-specific defects, and clinicopathologic/survival associations of β2 microglobulin (β2M), HLA-A, and HLA-B,-C heavy chains, as well as HLA class-II β chain in >700 immunotherapy-naïve NSCLCs from four independent cohorts. Genomic analysis of HLA genes in NSCLC was performed using two publicly available cohorts.

RESULTS

Cancer cell-specific downregulation of HLA markers was identified in 30.4% of cases. β2M was downregulated in 9.8% (70/714), HLA-A in 9% (65/722), HLA-B,-C in 12.1% (87/719), and HLA class-II in 17.7% (127/717) of evaluable samples. Concurrent downregulation of β2M, HLA-B,-C, and HLA class-II was commonly identified. Deleterious mutations in HLA genes were detected in <5% of lung malignancies. Tumors with cancer cell-specific β2M downregulation displayed reduced T cells and increased natural killer (NK)-cell infiltration. Samples with cancer cell HLA-A downregulation displayed modest increase in CD8⁺ T cells and NK-cell infiltration. Samples with cancer cell-selective HLA-B,-C or HLA class-II downregulation displayed reduced T cells and NK-cell infiltration. There was limited association of the markers with clinicopathologic variables and KRAS/EGFR mutations. Cancer cell-selective downregulation of the HLA subunits was associated with shorter overall survival.

CONCLUSIONS

Our results reveal frequent and differential defects in HLA class-I and HLA class-II protein subunit expression in immunotherapy-naïve NSCLCs associated with distinct tumor microenvironment composition and patient survival.

Abstract 5657: Objective measurement and significance of VISTA (PD-1H) expression in non-small cell lung cancer (NSCLC)

Introduction: VISTA (PD-1H) is a member of the B7 family of immune co-regulatory molecules and has been proposed as a novel anti-cancer immunotherapy target. The intra- and extracellular domains of VISTA show homology to PD-1 and PD-L1, respectively, suggesting a role in anti-tumor immune evasion. The expression of VISTA, its association with PD-1 axis components and biological role in human NSCLC are unknown.

Methods: Using multiplex quantitative immunofluorescence (QIF), we simultaneously measured the levels of VISTA (clone D1L2G, CST), PD-L1 (clone 405.9A11, CST) and PD-1 (clone EH33, CST) protein in 732 stage I-IV NSCLCs from 3 retrospective collections represented in tissue microarray format (cohort #1 [n=297, Yale], cohort #2 [n=329, Greece]; and cohort #3 [n=106, Yale]). To evaluate the tumor tissue distribution, VISTA was also selectively measured in cytokeratin+ tumor cells, CD3+ T-cells, CD4+ T-helper cells, CD8+ cytotoxic T-cells and CD20+ B-lymphocytes. Associations between the marker levels, clinico-pathological-molecular variables and survival were studied.

Results: VISTA protein was detected in all NSCLCs, showed a membranous staining pattern and was localized predominantly in the tumor cells in 27.4% of cases; and in the stromal compartment in 98.5%. Although VISTA was detected in all major tumor infiltrating lymphocyte (TIL) subsets, the signal was higher in CD20+ B-cells than in CD3+ T-lymphocytes (P&lt;0.05); and in CD4+ helper than in CD8+ cytotoxic T-cells (P&lt;0.001). Using the median score as cut point, elevated VISTA in tumor and/or stromal cells was significantly associated with high PD-L1, PD-1 protein expression and increased CD8+TILs in the cohorts (P&lt;0.001 - P&lt;0.05). No consistent association between VISTA levels and age, gender, smoking status, specific NSCLC histology, stage, EGFR/KRAS mutations and overall survival was found.

Conclusion: VISTA is expressed in the majority of NSCLCs and shows differential distribution in tumor/stromal cells and TIL subsets, suggesting a complex function as a ligand and receptor. Elevated expression of VISTA in NSCLC is associated with increased PD-1 axis targets and cytotoxic T-cell density, indicating its possible modulation by pro-inflammatory signals. Our results support VISTA as a candidate target for anti-cancer immunotherapy in NSCLC alone or in combination with PD-1 axis blockers.

Citation Format: Franz Villarroel-Espindola, Ila J. Datar, Vamsidhar Velcheti, David L. Rimm, Roy S. Herbst, Kurt A. Schalper. Objective measurement and significance of VISTA (PD-1H) expression in non-small cell lung cancer (NSCLC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5657. doi:10.1158/1538-7445.AM2017-5657

Abstract 5600: Simultaneous measurement and clinical significance of PD-1, LAG-3 and TIM-3 in non-small cell lung cancer (NSCLC)

Introduction: The ineffective anti-tumor immune response is characterized by increased immune suppressive signals in the tumor microenvironment. In particular, T-cells recognizing tumor antigens can express diverse immune inhibitory receptors mediating lymphocyte inactivation and limiting tumor rejection. Blockade of these receptors such as PD-1 induces prominent clinical benefit in patients with NSCLC. However, the expression and significance of additional potentially actionable immune inhibitory receptors in lung cancer is poorly understood.

Methods: After careful validation of assays and using multiplexed quantitative immunofluorescence (QIF) we measured the levels of CD3 (rabbit polyclonal, Dako), PD-1 (clone EH33, CST), LAG-3 (Clone 17B4, Abcam) and TIM-3 (clone D5D5R, CST) in 698 stages I-IV formalin-fixed paraffin embedded (FFPE) lung carcinomas represented in three tissue microarrays (cohort #1 [Yale n=186], cohort #2 [Yale n=192, and cohort #3 [Greece n=320]). We also included a collection of lung adenocarcinomas with molecular annotation (cohort #4 [Yale n=106]). The targets were measured in all cells of the preparation using fluorescence co-localization with DAPI and specifically in CD3-positive T-lymphocytes. Associations between the markers and with major clinico-pathological variables, driver mutations and survival were studied.

Results: All the targets were detected predominantly in CD3+ T-cells with membranous staining. Expression of PD-1, LAG-3 and TIM-3 in T-cells across all NSCLC cohorts was 68.7%, 39.7% and 55.8%, respectively. Elevated levels of PD-1, LAG-3 or TIM-3 were significantly associated with increased tumor infiltrating lymphocytes and with the co-expression of one or more of the other inhibitory receptors (P&lt;0.001). Simultaneous co-expression of all 3 markers was identified in 32.6% of cases. No consistent association was seen between the targets and patient age, gender, smoking status, clinical stage, tumor histology and overall survival. PD-1, TIM-3 and CD3 expression was significantly lower in EGFR and KRAS mutant lung adenocarcinomas than in tumors lacking mutations in these oncogenic drivers (P&lt;0.05).

Conclusion: PD-1, LAG-3 and TIM-3 are differentially expressed in NSCLC, show frequent co-expression and association with elevated CD3+ T-cells. Our results support the biological role of PD-1, LAG-3 and TIM-3 in NSCLC and suggest co-activation of these immune inhibitory pathways in a proportion of cases. Modulation of these receptors could enhance the anti-tumor immune response in lung cancer.

Citation Format: Ila J. Datar, Jun Wang, Nikita Mani, Franz Villarroel-Espindola, Patrick Ryan, Miguel F. Sanmamed, Kristen McEachern, David Jenkins, David L. Rimm, Leiping Chen, Roy Herbst, Kurt Schalper. Simultaneous measurement and clinical significance of PD-1, LAG-3 and TIM-3 in non-small cell lung cancer (NSCLC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5600. doi:10.1158/1538-7445.AM2017-5600

Abstract 124: Effect of RKIP on MMP expression and regulation of breast cancer metastasis

Raf Kinase Inhibitory Protein or RKIP was initially identified as a Raf-1 binding protein using the yeast 2-hybrid screen. RKIP inhibits the activation phosphorylation of MEK by Raf-1 by competitively inhibiting the binding of MEK to Raf-1 and thus exerting an inhibitory effect on the Raf-MEK-ERK pathway. RKIP has been identified as a metastasis suppressor gene. Metastasis is a complex multiple-step process. Expression of RKIP is low in cancer metastases. Although primary tumor growth was unaffected, re-expression of RKIP inhibits cancer metastasis. Mechanistically, RKIP constrains metastasis by inhibiting angiogenesis, local invasion, intravasation, and colonization. The molecular mechanism of how RKIP inhibits these individual steps remains undefined. Using an unbiased PCR based screening and by analyzing DNA microarray expression datasets we observed that the expression of multiple metalloproteases (MMP) including MMP1, MMP3, MMP10 and MMP13 were negatively correlated with RKIP expression in breast cancer cell lines and clinical samples. Since expression of MMPs by cancer cells is important for cancer metastasis, we hypothesize that RKIP may mediate suppression of breast cancer metastasis by inhibiting multiple MMPs. In this study we show that the expression signature of RKIP and MMPs is better at predicting high metastatic risk than the individual gene. Using a combination of loss- and gain-of-function approaches, we found that MMP13 is the cause of RKIP-mediated inhibition of local cancer invasion. Interestingly expression of MMP13 alone was not sufficient to reverse the inhibition of breast cancer cells metastasis to the lung due to the expression of RKIP. We found that RKIP negatively regulated MMP13 through the Erk2-Fra1 transcriptional axis and the repression of MMP13 by RKIP requires the presence of the a TPA-responsive element in the MMP13 proximal promoter. Together, our findings indicate that RKIP inhibits cancer cell invasion, in part, via MMP13 inhibition. These data also implicate RKIP in the regulation of MMPs transcription, suggesting a potential mechanism by which RKIP inhibits tumor progression and metastasis.

Citation Format: Ila J. Datar, Jingwei Feng, Gang Ren, Zehui Li, Xiaoliang Qiu, Fahd Al-Mulla, Milad S. Bitar, Miranda Yeung, Kam Yeung. Effect of RKIP on MMP expression and regulation of breast cancer metastasis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 124. doi:10.1158/1538-7445.AM2014-124

Abstract 5045: miR-10b mediates melanoma progression induced by BRAFV600E

The protein kinase BRaf plays an important role in the mitogen-activated protein kinase (MAPK) pathway initiated by Ras. Raf, after activated by Ras activates Erk and its downstream effectors to carry out normal cellular functions, which include differentiation, proliferation, survival and senescence. BRafV600E mutation has been implicated in 50-60% of all melanoma cases. It is a constitutively active mutation that has been linked to the progression of melanoma. Many microRNAs have been implicated in cancer proliferation and metastasis. Of special interest is the miR-10b, which is known to play a crucial role in tumor invasion and metastasis as previously observed in a mouse mammary tumor model. Our preliminary data show that miR-10b was upregulated in melanoma cell-lines that carried either N-Ras gain-of-function mutation or BRafV600E. BRafV600E knockdown in melanoma cell lines reduces the expression of TWIST, a transcriptional activator of miR-10b, as well as the expression of miR-10b. Further, BrafV600E is known to mediate senescence through several factors including the transcriptional regulator DMTF1. Concordantly, we detected an increase in the expression of DMTF1 on BRafV600E knockdown. Thus, we hypothesize that in melanoma, BRafV600E activates the expression of TWIST which then activates miR-10b, leading to inhibition of DMTF1 and ultimately a failure to bring about cell-cycle arrest.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5045. doi:1538-7445.AM2012-5045