Spatially Preserved Multi-Region Transcriptomic Subtyping and Biomarkers of Chemoimmunotherapy Outcome in Extensive-Stage Small Cell Lung Cancer.

PURPOSE: Transcriptomic subtyping holds promise for personalized therapy in extensive-stage small cell lung cancer (ES-SCLC). In this study, we aimed to assess intratumoral transcriptomic subtype diversity and to identify biomarkers of long-term chemoimmunotherapy benefit in human ES-SCLC. EXPERIMENTAL DESIGN: We analyzed tumor samples from 58 patients with ES-SCLC enrolled in two multicenter single-arm phase IIIb studies evaluating frontline chemoimmunotherapy in Spain: n = 32 from the IMfirst trial and n = 26 from the CANTABRICO trial. We used the GeoMx Digital Spatial Profiler system to perform multi-region transcriptomic analysis. For subtype classification, we performed hierarchical clustering using the relative expression of ASCL1 (SCLC-A), NEUROD1 (SCLC-N), POU2F3 (SCLC-P), and YAP1 (SCLC-Y). RESULTS: Subtype distribution was found to be similar between bothcohorts, except for SCLC-P, which was not identified in the CANTABRICO_DSP cohort. A total of 44% of the patients in both cohorts had tumors with multiple coexisting transcriptional subtypes. Transcriptional subtypes or subtype heterogeneity was not associated with outcomes. Most potential targets did not show subtype-specific expression. Consistently in both cohorts, tumors from patients with long-term benefit (time to progression ≥12 months) contained an IFNγ-dominated mRNA profile, including enhanced capacity for antigen presentation. Hypoxia and glycolytic pathways were associated with resistance to chemoimmunotherapy. CONCLUSIONS: This work suggests that intratumoral heterogeneity, inconsistent association with outcome, and unclear subtype-specific target expression might be significant challenges for subtype-based precision oncology in SCLC. Preexisting IFNγ-driven immunity and mitochondrial metabolism seem to be correlates of long-term efficacy in this study, although the absence of a chemotherapy control arm precludes concluding that these are predictive features specific for immunotherapy.

Facts and Hopes on Cancer Immunotherapy for Small Cell Lung Cancer.

Platinum-based chemotherapy plus PD1 axis blockade is the standard of care in the first-line treatment of extensive-stage small cell lung cancer (SCLC). Despite the robust and consistent increase in long-term survival with PD1 axis inhibition, the magnitude of the benefit from immunotherapy seems lower than that for other solid tumors. Several immune evasive mechanisms have been shown to be prominently altered in human SCLC, including T-cell exclusion, downregulation of components of the MHC class I antigen processing and presentation machinery, or upregulation of macrophage inhibitory checkpoints, among others. New immunotherapies aiming to target some of these dominant immune suppressive features are being intensively evaluated preclinically and clinically in SCLC. They include strategies to enhance the efficacy and/or reverse features that promote intrinsic resistance to PD1 axis inhibition (e.g., restoring MHC class I deficiency and targeting DNA damage response) and novel immunomodulatory agents beyond T-cell checkpoint blockers (e.g., T cell-redirecting strategies, antibody-drug conjugates, or macrophage checkpoint blockers). Among them, delta-like ligand 3-targeted bispecific T-cell engagers have shown the most compelling preliminary evidence of clinical efficacy and hold promise as therapies that might contribute to further improve patient outcomes in this disease. In this study, we first provide a brief overview of key tumor microenvironment features of human SCLC. Then, we update the current clinical evidence with immune checkpoint blockade and review other emerging immunotherapy strategies that are gaining increasing attention in SCLC. We finally summarize our future perspective on immunotherapy and precision oncology for this disease.

Future Perspectives in the Second Line Therapeutic Setting for Non-Oncogene Addicted Non-Small-Cell Lung Cancer.

Immune checkpoint inhibitors (ICIs) have revolutionized the management of non-oncogene addicted non-small-cell lung cancer (NSCLC). Blocking the anti-PD-1 axis represents the current standard of care in the first-line setting, with drugs administered either as monotherapy or in combination with chemotherapy. Despite notable successes achieved with ICIs, most of their long-term benefits are restricted to approximately 20% of patients. Consequently, the post-failure treatment landscape after failure to first-line treatment remains a complex challenge. Currently, docetaxel remains the preferred option, although its benefits remain modest as most patients do not respond or progress promptly. In recent times, novel agents and treatment combinations have emerged, offering fresh opportunities to improve patient outcomes. ICIs combined either with antiangiogenic or other novel immunotherapeutic compounds have shown promising preliminary activity. However, more mature data concerning specific combinations do not support their benefit over standard of care. In addition, antibody-drug conjugates seem to be the most promising alternative among all available compounds according to already-published phase I/II data that will be confirmed in soon-to-be-published phase III trial data. In this report, we provide a comprehensive overview of the current second-line treatment options and discuss future therapeutic perspectives.

ONCOS-102 plus pemetrexed and platinum chemotherapy in malignant pleural mesothelioma: a randomized phase 2 study investigating clinical outcomes and the tumor microenvironment.

BACKGROUND: ONCOS-102, an oncolytic adenovirus expressing granulocyte-macrophage colony-stimulating factor, can alter the tumor microenvironment to an immunostimulatory state. Combining ONCOS-102 with standard-of-care chemotherapy for malignant pleural mesothelioma (MPM) may improve treatment outcomes. METHODS: In this open-label, randomized study, patients with unresectable MPM received intratumoral ONCOS-102 (3×1011 virus particles on days 1, 4, 8, 36, 78, and 120) and pemetrexed plus cisplatin/carboplatin (from day 22), or pemetrexed plus cisplatin/carboplatin alone. The primary endpoint was safety. Overall survival (OS), progression-free survival, objective response rate, and tumor immunologic activation (baseline and day 36 biopsies) were also assessed. RESULTS: In total, 31 patients (safety lead-in: n=6, randomized: n=25) were enrolled. Anemia (15.0% and 27.3%) and neutropenia (40.0% and 45.5%) were the most frequent grade ≥3 adverse events (AEs) in the ONCOS-102 (n=20) and chemotherapy-alone (n=11) cohorts. No patients discontinued ONCOS-102 due to AEs. No statistically significant difference in efficacy endpoints was observed. There was a numerical improvement in OS (30-month OS rate 34.1% vs 0; median OS 20.3 vs 13.5 months) with ONCOS-102 versus chemotherapy alone in chemotherapy-naïve patients (n=17). By day 36, ONCOS-102 was associated with increased T-cell infiltration and immune-related gene expression that was not observed in the control cohort. Substantial immune activation in the tumor microenvironment was associated with survival at month 18 in the ONCOS-102 cohort. CONCLUSIONS: ONCOS-102 plus pemetrexed and cisplatin/carboplatin was well tolerated by patients with MPM. In injected tumors, ONCOS-102 promoted a proinflammatory environment, including T-cell infiltration, which showed association with survival at month 18.

SEOM-GECP Clinical guidelines for diagnosis, treatment and follow-up of small-cell lung cancer (SCLC) (2022)

SEOM-GECP Clinical guidelines for diagnosis, treatment and follow-up of small-cell lung cancer (SCLC) (2022) (AU)

A narrative review of methods for the identification of ALK fusions in patients with non-small cell lung carcinoma.

Background and Objective: This narrative review is intended to provide pragmatic knowledge of current methods for the search of anaplastic lymphoma kinase (ALK) fusions in patients with non-small cell lung carcinoma (NSCLC). This information is very timely, because a recent survey has identified that almost 50% of patients with advanced NSCLC were not candidates for targeted therapies because of biomarker testing issues. Methods: PubMed was searched from January 1st, 2012 to February 28th, 2023 using the following keywords: "ALK" and "lung", including reviews and our own work. Key Content and Findings: Testing rates have not reached 85% among patients' candidates to ALK inhibition. The advantages and disadvantages of the different analytical options [immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), real-time polymerase chain reaction and next-generation sequencing (NGS)] are discussed. The key factor for success in ALK testing is a deep understanding of the concept of "molecular redundancy". This notion has been recommended and endorsed by all the major professional organizations in the field and can be summarized as follows: "laboratories should ensure that test results that are unexpected, discordant, equivocal, or otherwise of low confidence are confirmed or resolved using an alternative method or sample". In-depth knowledge of the different ALK testing methodologies can help clinical and molecular tumor boards implement and maintain sensible algorithms for a rapid and effective detection of predictive biomarkers in patients with NSCLC. Conclusions: Multimodality testing has the potential to increase both the testing rate and the accuracy of ALK fusion identification.

PD-1/PD-L1 Inhibitors as Monotherapy in the First-Line Treatment of Advanced Non-Small Cell Lung Cancer Patients with High PD-L1 Expression: An Expert Position Statement.

INTRODUCTION: There are currently three first-line immunotherapy options used as monotherapy in advanced non-small cell lung cancer (NSCLC) patients with high programmed death ligand 1 (PD-L1) expression (≥50%). This manuscript aims to evaluate the available data on atezolizumab (AT), cemiplimab (CEMI), and pembrolizumab (PEMBRO) and to study the results obtained during pivotal trials, especially regarding patient subgroups. METHODS: Nominal group and Delphi techniques were used. Eight Spanish experts in lung cancer (the scientific committee of the project) analyzed the use of immunotherapy monotherapy as first-line treatment in patients with NSCLC and high PD-L1 expression. The expert scientific committee formulated several statements based on a scientific review and their own clinical experience. Subsequently, 17 additional Spanish lung cancer experts were selected to appraise the committee's statements through two Delphi rounds. They completed a Delphi round via an online platform and voted according to a scale from 1 (strongly disagree) to 10 (strongly agree). The statements were approved if ≥70% of experts voted 7 or more. RESULTS: A total of 20 statements were proposed covering the following areas: (1) general characteristics of pivotal clinical trials; (2) overall main outcomes of pivotal clinical trials; and (3) subgroup analysis. All statements reached consensus in the first round. CONCLUSIONS: AT, CEMI, and PEMBRO as monotherapy can be considered the standard of care in patients with advanced NSCLC and high PD-L1 expression (≥50%). Moreover, some differences noted among the drugs analyzed in this document might facilitate treatment decision-making, especially in clinically relevant patient subgroups, when using PD-1/PD-L1 inhibitors. The high level of agreement reached among experts supports the proposed statements.

SEOM-GECP Clinical guidelines for diagnosis, treatment and follow-up of small-cell lung cancer (SCLC) (2022).

Small-cell lung cancer (SCLC) is a highly aggressive malignancy comprising approximately 15% of lung cancers. Only one-third of patients are diagnosed at limited-stage (LS). Surgical resection can be curative in early stages, followed by platinum-etoposide adjuvant therapy, although only a minority of patients with SCLC qualify for surgery. Concurrent chemo-radiotherapy is the standard of care for LS-SCLC that is not surgically resectable, followed by prophylactic cranial irradiation (PCI) for patients without progression. For extensive-stage (ES)-SCLC, a combination of platinum and etoposide has historically been a mainstay of treatment. Recently, the efficacy of programmed death-ligand 1 inhibitors combined with chemotherapy has become the new front-line standard of care for ES-SCLC. Emerging knowledge regarding SCLC biology, including genomic characterization and molecular subtyping, and new treatment approaches will potentially lead to advances in SCLC patient care.

PTEN Loss Confers Resistance to Anti-PD-1 Therapy in Non-Small Cell Lung Cancer by Increasing Tumor Infiltration of Regulatory T Cells.

Immunotherapy resistance in non-small cell lung cancer (NSCLC) may be mediated by an immunosuppressive microenvironment, which can be shaped by the mutational landscape of the tumor. Here, we observed genetic alterations in the PTEN/PI3K/AKT/mTOR pathway and/or loss of PTEN expression in >25% of patients with NSCLC, with higher frequency in lung squamous carcinomas (LUSC). Patients with PTEN-low tumors had higher levels of PD-L1 and PD-L2 and showed worse progression-free survival when treated with immunotherapy. Development of a Pten-null LUSC mouse model revealed that tumors with PTEN loss were refractory to antiprogrammed cell death protein 1 (anti-PD-1), highly metastatic and fibrotic, and secreted TGFß/CXCL10 to promote conversion of CD4+ lymphocytes into regulatory T cells (Treg). Human and mouse PTEN-low tumors were enriched in Tregs and expressed higher levels of immunosuppressive genes. Importantly, treatment of mice bearing Pten-null tumors with TLR agonists and anti-TGFß antibody aimed to alter this immunosuppressive microenvironment and led to tumor rejection and immunologic memory in 100% of mice. These results demonstrate that lack of PTEN causes immunotherapy resistance in LUSCs by establishing an immunosuppressive tumor microenvironment that can be reversed therapeutically. SIGNIFICANCE: PTEN loss leads to the development of an immunosuppressive microenvironment in lung cancer that confers resistance to anti-PD-1 therapy, which can be overcome by targeting PTEN loss-mediated immunosuppression.

Cost-Effectiveness of Next-Generation Sequencing Versus Single-Gene Testing for the Molecular Diagnosis of Patients With Metastatic Non-Small-Cell Lung Cancer From the Perspective of Spanish Reference Centers.

PURPOSE: The aim of this study was to assess the cost-effectiveness of using next-generation sequencing (NGS) versus single-gene testing (SgT) for the detection of genetic molecular subtypes and oncogenic markers in patients with advanced non-small-cell lung cancer (NSCLC) in the setting of Spanish reference centers. METHODS: A joint model combining decision tree with partitioned survival models was developed. A two-round consensus panel was performed to describe clinical practice of Spanish reference centers, providing data on testing rate, prevalence of alterations, turnaround times, and treatment pathways. Treatment efficacy data and utility values were obtained from the literature. Only direct costs (euros, 2022), obtained from Spanish databases, were included. A lifetime horizon was considered, so a 3% discount rate for future costs and outcomes was considered. Both deterministic and probabilistic sensitivity analyses were performed to assess uncertainty. RESULTS: A target population of 9,734 patients with advanced NSCLC was estimated. If NGS was used instead of SgT, 1,873 more alterations would be detected and 82 more patients could potentially be enrolled in clinical trials. In the long term, using NGS would provide 1,188 additional quality-adjusted life-years (QALYs) in the target population compared with SgT. On the other hand, the incremental cost of NGS versus SgT in the target population was €21,048,580 euros for a lifetime horizon (€1,333,288 for diagnosis phase only). The obtained incremental cost-utility ratios were €25,895 per QALY gained, below the standard cost-effectiveness thresholds. CONCLUSION: Using NGS in Spanish reference centers for the molecular diagnosis of patients with metastatic NSCLC would be a cost-effective strategy over SgT.

At the crossroads of immunotherapy for oncogene-addicted subsets of NSCLC.

Non-small-cell lung cancer (NSCLC) has become a paradigm of precision medicine, with the discovery of numerous disease subtypes defined by specific oncogenic driver mutations leading to the development of a range of molecularly targeted therapies. Over the past decade, rapid progress has also been made in the development of immune-checkpoint inhibitors (ICIs), especially antagonistic antibodies targeting the PD-L1-PD-1 axis, for the treatment of NSCLC. Although many of the major oncogenic drivers of NSCLC are associated with intrinsic resistance to ICIs, patients with certain oncogene-driven subtypes of the disease that are highly responsive to specific targeted therapies might also derive benefit from immunotherapy. However, the development of effective immunotherapy approaches for oncogene-addicted NSCLC has been challenged by a lack of predictive biomarkers for patient selection and limited knowledge of how ICIs and oncogene-directed targeted therapies should be combined. Therefore, whether ICIs alone or with chemotherapy or even in combination with molecularly targeted agents would offer comparable benefit in the context of selected oncogenic driver alterations to that observed in the general unselected NSCLC population remains an open question. In this Review, we discuss the effects of oncogenic driver mutations on the efficacy of ICIs and the immune tumour microenvironment as well as the potential vulnerabilities that could be exploited to overcome the challenges of immunotherapy for oncogene-addicted NSCLC.

Spatially resolved proteomic profiling identifies tumor cell CD44 as a biomarker associated with sensitivity to PD-1 axis blockade in advanced non-small-cell lung cancer.

BACKGROUND: Most patients with advanced non-small-cell lung cancer (NSCLC) fail to derive significant benefit from programmed cell death protein-1 (PD-1) axis blockade, and new biomarkers of response are needed. In this study, we aimed to discover and validate spatially resolved protein markers associated with sensitivity to PD-1 axis inhibition in NSCLC. METHODS: We initially assessed a discovery cohort of 56 patients with NSCLC treated with PD-1 axis inhibitors at Yale Cancer Center. Using the GeoMx Digital Spatial Profiling (DSP) system, 71 proteins were measured in spatial context on each spot in a tissue microarray. We used the AQUA method of quantitative immunofluorescence (QIF) to orthogonally validate candidate biomarkers. For external independent validation, we assessed whole tissue sections derived from 128 patients with NSCLC treated with single-agent PD-1 axis inhibitors at the 12 de Octubre Hospital (Madrid) using DSP. We further analyzed two immunotherapy untreated cohorts to address prognostic significance (n=252 from Yale Cancer Center; n=124 from University Clinic of Navarra) using QIF and DSP, respectively. RESULTS: Using continuous log-scaled data, we identified CD44 expression in the tumor compartment (pan-cytokeratin (CK)+) as a novel predictor of prolonged progression-free survival (PFS) (multivariate HR=0.68, p=0.043) in the discovery set. We validated by QIF that tumor CD44 levels assessed as continuous QIF scores were associated with longer PFS (multivariate HR=0.31, p=0.022) and overall survival (multivariate HR=0.29, p=0.038). Using DSP in an independent immunotherapy treated cohort, we validated that CD44 levels in the tumor compartment, but not in the immune compartment (panCK-/CD45+), were associated with clinical benefit (OR=1.22, p=0.018) and extended PFS under PD-1 axis inhibition using the highest tertile cutpoint (multivariate HR=0.62, p=0.03). The effect of tumor cell CD44 in predicting PFS remained significant after correcting for programmed death-ligand 1 (PD-L1) Tumor Proportion Score (TPS) in both cohorts. High tumor cell CD44 was not prognostic in the absence of immunotherapy. Using DSP data, intratumoral regions with elevated tumor cell CD44 expression showed prominent (fold change>1.5, adjusted p<0.05) upregulation of PD-L1, TIM-3, ICOS, and CD40 in two independent cohorts. CONCLUSIONS: This work highlights CD44 as a novel indicative biomarker of sensitivity to PD-1 axis blockade that might help to improve immunotherapy strategies for NSCLC.

Discovery of Biomarkers of Resistance to Immune Checkpoint Blockade in NSCLC Using High-Plex Digital Spatial Profiling.

INTRODUCTION: Despite the clinical efficacy of immune checkpoint inhibitors (ICIs) in NSCLC, only approximately 20% of patients remain disease-free at 5 years. Here, we use digital spatial profiling to find candidate biomarker proteins associated with ICI resistance. METHODS: Pretreatment samples from 56 patients with NSCLC treated with ICI were analyzed using the NanoString GeoMx digital spatial profiling method. A panel of 71 photocleavable oligonucleotide-labeled primary antibodies was used for protein detection in four molecular compartments (tumor, leukocytes, macrophages, and immune stroma). Promising candidates were orthogonally validated with quantitative immunofluorescence. Available pretreatment samples from 39 additional patients with NSCLC who received ICI and 236 non-ICI-treated patients with operable NSCLC were analyzed to provide independent cohort validation. RESULTS: Biomarker discovery using the protein-based molecular compartmentalization strategy allows 284 protein variables to be assessed for association with ICI resistance by univariate analysis using continuous log-scaled data. Of the 71 candidate protein biomarkers, CD66b in the CD45+CD68 molecular compartment (immune stroma) predicted significantly shorter overall survival (OS) (hazard ratio [HR] 1.31, p = 0.016) and was chosen for validation. Orthogonal validation by quantitative immunofluorescence illustrated that CD66b was associated with resistance to ICI therapy but not prognostic for poor outcomes in untreated NSCLC (discovery cohort [OS HR 2.49, p = 0.026], validation cohort [OS HR 2.05, p = 0.046], non-ICI-treated cohort [OS HR 1.67, p = 0.06]). CONCLUSIONS: Using the technique, we have discovered that CD66b expression is indicative of resistance to ICI therapy in NSCLC. Given that CD66b identifies neutrophils, further studies are warranted to characterize the role of neutrophils in ICI resistance.

Development of an immunohistochemical assay for Siglec-15.

Siglec-15, a member of sialic-acid binding immunoglobulin type lectins, is normally expressed by myeloid cells and upregulated in some human cancers and represents a promising new target for immunotherapy. While PD-L1 blockade is an important strategy for immunotherapy, its effectiveness is limited. The expression of Siglec-15 has been demonstrated to be predominantly mutually exclusive to PD-L1 in certain cancer histologies. Thus, there is significant opportunity for Siglec-15 as an immunotherapeutic target for patients that do not respond to PD-1/PD-L1 inhibition. The aim of this study was to prospectively develop an immunohistochemical (IHC) assay for Siglec-15 to be used as a companion diagnostic for future clinical trials. Here, we create and validate an IHC assay with a novel recombinant antibody to the cytoplasmic domain of Siglec-15. To find an enriched target, this antibody was first used in a quantitative fluorescence (QIF) assay to screen a broad range of tumor histologies to determine tumor types where Siglec-15 demonstrated high expression. Based on this and previous data, we focused on development of a chromogenic IHC assay for lung cancer. Then we developed a scoring system for this assay that has high concordance amongst pathologist readers. We then use this chromogenic IHC assay to test the expression of Siglec-15 in two cohorts of NSCLC. We found that this assay shows a higher level of staining in both tumor and immune cells compared to previous QIF assays utilizing a polyclonal antibody. However, similar to that study, only a small percentage of positive Siglec-15 cases showed high expression for PD-L1. This validated assay for Siglec-15 expression may support development of a companion diagnostic assay to enrich for patients expressing the Siglec-15 target for therapy.

Comprehensive Characterization of Human Lung Large Cell Carcinoma Identifies Transcriptomic Signatures with Potential Implications in Response to Immunotherapy.

Lung cancer is the leading cause of cancer mortality worldwide, with non-small cell lung cancer (NSCLC) being the most prevalent histology. While immunotherapy with checkpoint inhibitors has shown outstanding results in NSCLC, the precise identification of responders remains a major challenge. Most studies attempting to overcome this handicap have focused on adenocarcinomas or squamous cell carcinomas. Among NSCLC subtypes, the molecular and immune characteristics of lung large cell carcinoma (LCC), which represents 10% of NSCLC cases, are not well defined. We hypothesized that specific molecular aberrations may impact the immune microenvironment in LCC and, consequently, the response to immunotherapy. To that end, it is particularly relevant to thoroughly describe the molecular genotype-immunophenotype association in LCC-to identify robust predictive biomarkers and improve potential benefits from immunotherapy. We established a cohort of 18 early-stage, clinically annotated, LCC cases. Their molecular and immune features were comprehensively characterized by genomic and immune-targeted sequencing panels along with immunohistochemistry of immune cell populations. Unbiased clustering defined two novel subgroups of LCC. Pro-immunogenic tumors accumulated certain molecular alterations, showed higher immune infiltration and upregulated genes involved in potentiating immune responses when compared to pro-tumorigenic samples, which favored tumoral progression. This classification identified a set of biomarkers that could potentially predict response to immunotherapy. These results could improve patient selection and expand potential benefits from immunotherapy.

Extensive-Stage Small-Cell Lung Cancer: First-Line and Second-Line Treatment Options.

Extensive-stage small-cell lung cancer is a therapeutically challenging disease. After more than two decades without clinical progress, the addition of programmed cell death protein 1 axis blockade to platinum-based chemotherapy has demonstrated sustained overall survival benefit and represents the current standard of care in the first-line setting. Despite this benefit, resistance emerges relatively rapidly in virtually all patients. Although newer treatments are being incorporated in the relapse setting, marked therapeutic resistance is typically observed in patients with relapsed small-cell lung cancer (SCLC), underscoring the need of developing more effective therapies in this setting. Notably, recent progress in the understanding of the molecular biology of SCLC might bring possibilities toward molecularly informed therapeutic strategies for patients with SCLC, which could have a significant impact for improving outcomes in this disease. Here, we review current treatment options and recent progress made in the first-line and relapsed SCLC, including the role of biomarkers and new evolving therapeutic strategies.

Association of PD-1/PD-L1 Co-location with Immunotherapy Outcomes in Non-Small Cell Lung Cancer.

PURPOSE: Programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) interaction suppresses local T-cell responses and promotes peripheral tolerance. In the current study, we focus on PD-1/PD-L1 co-location as a surrogate for this interaction and assess its association with immunotherapy outcomes in patients with non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: Pretreatment biopsies from a retrospective cohort of 154 immunotherapy-treated patients with advanced NSCLC were analyzed. Expression of PD-1 and PD-L1 was assessed by multiplexed quantitative immunofluorescence (QIF) and PD-1 expression in the same pixels as PD-L1 (called a co-location score) was measured using an algorithm to define overlapping expression areas. Co-location scores were correlated with immunotherapy outcomes and PD-L1 tumor proportion score. RESULTS: PD-1/PD-L1 co-location score was associated with best overall response (P = 0.0012), progression-free survival (P = 0.0341), and overall survival after immunotherapy (P = 0.0249). The association was driven by patients receiving immune checkpoint inhibitors in the second or subsequent line of treatment. PD-L1 tumor proportion score by IHC was also correlated with best overall response and progression-free survival. PD-L1 measured within the tumor compartment by QIF did not show any significant association with either best overall response or overall survival. Finally, co-location score was not associated with PD-L1 expression by either method. CONCLUSIONS: On the basis of our findings, co-location score shows promise as a biomarker associated with outcome after immunotherapy. With further validation, it could have value as a predictive biomarker for the selection of patients with NSCLC receiving treatment with immune checkpoint inhibitors.

Multiplex Quantitative Analysis of Tumor-Infiltrating Lymphocytes, Cancer-Associated Fibroblasts, and CD200 in Pancreatic Cancer.

Pancreatic cancer is marked by a desmoplastic tumor microenvironment and low tumor immunogenicity, making it difficult for immunotherapy drugs to improve outcomes for patients. Tumor-infiltrating lymphocytes (TILs) and cancer-associated fibroblasts (CAFs) are seen in the tumor microenvironment of patients with pancreatic ductal adenocarcinoma (PDAC). In this work, we sought to characterize the expression levels and potential prognostic value of TILs (CD4, CD8, and CD20) and CAFs (Thy-1, FAP, and SMA) in a large retrospective cohort of PDAC patients. Additionally, we investigated the expression levels and prognostic significance of CD200, an immunoinhibitory protein that has shown interest as a potential target for immune checkpoint blockade. We measured the expression levels of these seven proteins with multiplexed immunofluorescence staining and quantitative immunofluorescence (QIF). We found CD8 and FAP to be independent predictors of progression-free survival and overall survival. CD200 was found to be heterogeneously expressed in both the tumor and stromal compartments of PDAC, with the majority of patients having positive stromal expression and negative tumor expression. This work demonstrates the potential clinical utility of CD8 and FAP in PDAC patients, and it sheds light on the expression patterns of CD200 in pancreatic cancer as the protein is being tested as a target for immune checkpoint blockade.