Drug Response of Patient-Derived Lung Cancer Cells Predicts Clinical Outcomes of Targeted Therapy

Intratumor heterogeneity leads to different responses to targeted therapies, even within patients whose tumors harbor identical driver oncogenes. This study examined clinical outcomes according to a patient-derived cell (PDC)-based drug sensitivity test in lung cancer patients treated with targeted therapies. From 487 lung cancers, 397 PDCs were established with a success rate of 82%. In 139 PDCs from advanced non-small-cell lung cancer (NSCLC) patients receiving targeted therapies, the standardized area under the curve (AUC) values for the drugs was significantly correlated with their tumor response (p = 0.002). Among 59 chemo-naive EGFR/ALK-positive NSCLC patients, the PDC non-responders showed a significantly inferior response rate (RR) and progression-free survival (PFS) for the targeted drugs than the PDC responders (RR, 25% vs. 78%, p = 0.011; median PFS, 3.4 months [95% confidence interval (CI), 2.8-4.1] vs. 11.8 months [95% CI, 6.5-17.0], p < 0.001). Of 25 EGFR-positive NSCLC patients re-challenged with EGFR inhibitors, the PDC responder showed a higher RR than the PDC non-responder (42% vs. 15%). Four patients with wild-type EGFR or uncommon EGFR-mutant NSCLC were treated with EGFR inhibitors based on their favorable PDC response to EGFR inhibitors, and two patients showed dramatic responses. Therefore, the PDC-based drug sensitivity test results were significantly associated with clinical outcomes in patients with EGFR- or ALK-positive NSCLC. It may be helpful for predicting individual heterogenous clinical outcomes beyond genomic alterations.

Tumor Microenvironment Modulation by Neoadjuvant Erlotinib Therapy and Its Clinical Impact on Operable EGFR-Mutant Non-Small Cell Lung Cancer

PURPOSE

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors have greatly improved survival in EGFR-mutant (EGFRm) non-small cell lung cancer (NSCLC); however, their effects on the tumor microenvironment (TME) are unknown. We assessed the changes induced by neoadjuvant erlotinib therapy (NE) in the TME of operable EGFRm NSCLC.

MATERIALS AND METHODS

This was a single-arm phase II trial for neoadjuvant/adjuvant erlotinib therapy in patients with stage II/IIIA EGFRm NSCLC (EGFR exon 19 deletion or L858R mutations). Patients received up to 2 cycles of NE (150 mg/day) for 4 weeks, followed by surgery and adjuvant erlotinib or vinorelbine plus cisplatin therapy depending on observed NE response. TME changes were assessed based on gene expression analysis and mutation profiling.

RESULTS

A total of 26 patients were enrolled; the median age was 61, 69% were female, 88% were stage IIIA, and 62% had L858R mutation. Among 25 patients who received NE, the objective response rate was 72% (95% confidence interval [CI], 52.4 to 85.7). The median disease-free and overall survival (OS) were 17.9 (95% CI, 10.5 to 25.4) and 84.7 months (95% CI, 49.7 to 119.8), respectively. Gene set enrichment analysis in resected tissues revealed upregulation of interleukin, complement, cytokine, transforming growth factor β, and hedgehog pathways. Patients with upregulated pathogen defense, interleukins, and T-cell function pathways at baseline exhibited partial response to NE and longer OS. Patients with upregulated cell cycle pathways at baseline exhibited stable/progressive disease after NE and shorter OS.

CONCLUSION

NE modulated the TME in EGFRm NSCLC. Upregulation of immune-related pathways was associated with better outcomes.

Nivolumab after Induction Chemotherapy in Previously Treated Non-Small-Cell Lung Cancer Patients with Low PD-L1 Expression

This study aimed to investigate whether cyclophosphamide (C) and adriamycin (A) induction therapy (IT) prior to nivolumab could enhance the efficacy of nivolumab in previously treated patients with non-squamous (NSQ) non-small-cell lung cancer (NSCLC) with less than 10% programmed death-ligand 1 (PD-L1) expression. Twenty-two enrolled patients received four cycles of CA-IT every 3 weeks. Nivolumab was given 360 mg every 3 weeks from the second cycle and 480 mg every 4 weeks after four cycles of CA-IT. The median progression-free survival (PFS) and overall survival (OS) were 2.4 months and 11.6 months, respectively. Fluorescence-activated cell sorting revealed the lowest ratio of myeloid-derived suppressor cells (MDSCs) to CD8+T-cells in the responders. Proteomic analysis identified a consistent upregulation of extracellular matrix-receptor interactions and phagosome pathways in the responders. Among the differentially expressed proteins, the transferrin receptor protein (TFRC) was higher in the responders before treatment (fold change > 1.2). TFRC validation with an independent cohort showed the prognostic significance of either OS or PFS in patients with low PD-L1 expression. In summary, CA-IT did not improve nivolumab efficacy in NSQ-NSCLCs with low PD-L1 expression; however, it induced decreasing MDSC, resulting in a durable response. Higher baseline TFRC levels predicted a favorable response to nivolumab in NSCLC with low PD-L1 expression.

Clinical utility of a plasma-based comprehensive genomic profiling test in patients with non-small cell lung cancer in Korea

OBJECTIVES

Plasma-based comprehensive circulating cell-free DNA (cfDNA) next generation sequencing (NGS) has shown utility in advanced non-small cell lung cancer (aNSCLC). The aim of this study was to determine the feasibility of cfDNA-based NGS to identify actionable gene alterations in patients with aNSCLC.

PATIENTS AND METHODS

This single-center non-interventional retrospective study evaluated Korean patients with biopsy-confirmed stage III/IV non-squamous aNSCLC. Tissue biopsy samples were collected at baseline, and/or at progression and analysed with Standard of Care (SOC) testing; cfDNA was analyzed by NGS in some patients concurrently.

RESULTS

aNSCLC patients with cfDNA test results (n = 405) were categorized into three groups: treatment naïve (n = 182), progressive aNSCLC after chemotherapy and/or immunotherapy (n = 157), and progressive aNSCLC after tyrosine kinase inhibitors (TKIs) (n = 66). Clinically informative driver mutations were identified for 63.5% of patients which were classified as OncoKB Tiers 1 (44.2%), 2 (3.4%), tier 3 (18.9%), and 4 (33.5%). Concordance between cfDNA NGS and tissue SOC methods for concurrently collected tissue samples (n = 221) with common EGFR mutations or ALK/ROS1 fusions was 96.9%. cfDNA analysis identified tumor genomic alterations in 13 patients that were unidentified with tissue testing, enabling initiation of targeted treatment.

CONCLUSIONS

In clinical practice, results of cfDNA NGS are highly concordant with those of tissue SOC testing in aNSCLC patients. Plasma analysis identified actionable alterations that were missed or not evaluated by tissue testing, enabling the initiation of targeted therapy. Results from this study add to the body of evidence in the support routine use of cfDNA NGS for patients with aNSCLC.

Lazertinib in pretreated EGFR T790M-mutated advanced non-small cell lung cancer: A real-world multicenter study

INTRODUCTION

Lazertinib is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) that provides a high level of selectivity for sensitizing and p.Thr790Met (T790M) EGFR mutations. We aimed to collect real-world data regarding the efficacy and safety of lazertinib.

METHODS

This study included patients treated with lazertinib for T790M-mutated non-small cell lung cancer who had previously been treated with an EGFR-TKI. The primary outcome measure was progression-free survival (PFS). Additionally, this study evaluated overall survival (OS), time-to-treatment failure (TTF), duration of response (DOR), objective response rate (ORR) and disease control rate (DCR). Drug safety was also assessed.

RESULTS

In a study of 103 patients, 90 received lazertinib as a second- or third-line therapy. The ORR and DCR were 62.1% and 94.2%, respectively. The median follow-up duration was 11.1 months, and the median PFS period was 13.9 (95% confidence interval [CI], 11.0-not reached [NR]) months. OS, DOR, and TTF had not yet been determined. In a subgroup of 33 patients with evaluable brain metastases, the intracranial DCR and ORR were 93.5% and 57.6%, respectively. The median intracranial PFS period was 17.1 (95% CI, 13.9-NR) months. Approximately 17.5% of patients had dose modification or discontinuation due to adverse events, with the most common being grade 1 or 2 paresthesia.

CONCLUSIONS

The efficacy and safety of lazertinib were recapitulated in a real-world study reflecting routine clinical practice in Korea, showing durable disease control both systematically and intracranially, with manageable side effects.

Abstract 2805: Pharmacogenomic platform using patient-derived cells to delineate tumor heterogeneity and therapeutic response of refractory lung cancer

A pharmacogenomic platform using patient-derived cells (PDCs) was established to identify the underlying resistance mechanisms and tailored treatment for advanced or refractory lung cancer patients. Drug sensitivity screening was acquired from short-term PDC culture and multi-omics datasets were acquired from lung cancer PDCs (n = 199). Integrative analysis was performed to explore susceptible drug candidates from genetic variants, gene expression, and clinical profiles. To demonstrate PDC heterogeneity and its therapeutic response, cellular subpopulation was identified from single cell transcriptome from the patients (n = 8) harboring EGFR mutations with poor response to EGFR-TKIs. Mutation and gene expression profile of our PDC samples conserved with lung cancer tissue. Poor survival mutations were observed in KRAS, PDGFA, KEAP1, and MET. EGFR rare variants facilitated fast progression as well as poor susceptibility in EGFR-TKIs. PDC therapeutic subtypes classified patients into five groups: (1) epithelial-to-mesenchymal transition (EMT)-like (30.6 %), (2) EGFR-dominant (21.4 %), (3) stemness (19.4 %), (4) angiogenesis (17.3 %), and (5) inflammatory (11.2 %). The subtypes implicated in distinct pathway regulation activation,

variant enrichment, pathologic type, and survival as well as therapeutic candidates. Meanwhile, single cell transcriptome uncovered IDO1 and MET activation of EGFR-TKI resistance cancer cells. Stromal cell clusters exhibited the variety according to combinatorial immunotherapy response. While VEGFA+, and TOP2A+ clusters exhibited well response to angiogenesis and DNA damage target drug combinations of patients, CALB2+ cluster was clearly abundant to non-responder patients. We could detect angiogenesis (dasatinib) and DNA damage (irinotecan) drug candidates according to stromal clusters’ scoring from bulk PDC samples. Our PDC platform recapitulated the molecular characteristics of solid lung tumor tissues including tumor microenvironment. Uncovered molecular mechanism implied drug candidates.

Citation Format: Charny Park, Sehwa Hong, Mihwa Hwang, Youngjoo Lee, Bo Ram Song, Eun Hye Kang, Hanna Sim, Beung-Chul Ahn, Kum Hui Hwang, Namhee Yu, Sunshin Kim, Ji-Youn Han. Pharmacogenomic platform using patient-derived cells to delineate tumor heterogeneity and therapeutic response of refractory lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2805.

Patient-derived cell-based pharmacogenomic assessment to unveil underlying resistance mechanisms and novel therapeutics for advanced lung cancer

BACKGROUND

A pharmacogenomic platform using patient-derived cells (PDCs) was established to identify the underlying resistance mechanisms and tailored treatment for patients with advanced or refractory lung cancer.

METHODS

Drug sensitivity screening and multi-omics datasets were acquired from lung cancer PDCs (n = 102). Integrative analysis was performed to explore drug candidates according to genetic variants, gene expression, and clinical profiles.

RESULTS

PDCs had genomic characteristics resembled with those of solid lung cancer tissues. PDC molecular subtyping classified patients into four groups: (1) inflammatory, (2) epithelial-to-mesenchymal transition (EMT)-like, (3) stemness, and (4) epithelial growth factor receptor (EGFR)-dominant. EGFR mutations of the EMT-like subtype were associated with a reduced response to EGFR-tyrosine kinase inhibitor therapy. Moreover, although RB1/TP53 mutations were significantly enriched in small-cell lung cancer (SCLC) PDCs, they were also present in non-SCLC PDCs. In contrast to its effect in the cell lines, alpelisib (a PI3K-AKT inhibitor) significantly inhibited both RB1/TP53 expression and SCLC cell growth in our PDC model. Furthermore, cell cycle inhibitors could effectively target SCLC cells. Finally, the upregulation of transforming growth factor-β expression and the YAP/TAZ pathway was observed in osimertinib-resistant PDCs, predisposing them to the EMT-like subtype. Our platform selected XAV939 (a WNT-TNKS-β-catenin inhibitor) for the treatment of osimertinib-resistant PDCs. Using an in vitro model, we further demonstrated that acquisition of osimertinib resistance enhances invasive characteristics and EMT, upregulates the YAP/TAZ-AXL axis, and increases the sensitivity of cancer cells to XAV939.

CONCLUSIONS

Our PDC models recapitulated the molecular characteristics of lung cancer, and pharmacogenomics analysis provided plausible therapeutic candidates.

Real World Characteristics and Clinical Outcomes of HER2-Mutant Non-Small Cell Lung Cancer Patients Detected by Next-Generation Sequencing

PURPOSE

This study was conducted to investigate the clinical characteristics of patients with advanced non-small cell lung cancer (NSCLC) harboring human epidermal growth factor receptor 2 (HER2) mutations and to evaluate response to standard treatment and HER2-targeted agents.

Materials and Methods

Using tissue and/or blood next-generation sequencing, we identified 44 patients with NSCLC harboring HER2 mutations who were treated at Severance Hospital between December 2016 and February 2021. Clinical data, including patient characteristics, mutation status, incidence of metastasis for distant lesions, and response to chemotherapy, were retrospectively analyzed.

RESULTS

The median age was 58 years, and 61% of the patients were female. Most patients (64%) were never-smokers. Adenocarcinoma was the most predominant subtype (98%). A total of 66% of the patients had extrathoracic metastatic lesions, and 32% had intracranial lesions at initial presentation. The median time to the development of brain metastasis was 15.6 months (range, 2.4 to 43.7). The most common type of HER2 mutation was 12 base pair in-frame insertion in exon 20, A775_G776insYVMA. Of the 44 patients, two had concomitant driver mutations, one with epidermal growth factor receptor (EGFR) mutation (V769M), and one with BRAF mutation (V600E). Patients treated with pemetrexed-based chemotherapy (75%) had an overall response rate (ORR) and progression-free survival (PFS) of 30% and 8.3 months (95% confidence interval [CI], 3.9 to 12.7), respectively. The ORR and PFS of HER2-targeted agent treated patients (14%) were 0.0% and 1.9 months (95% CI, 0.1 to 2.8), respectively.

CONCLUSION

Given its distinct characteristics and treatment responses, novel treatment strategies for HER2-mutant NSCLC should be developed promptly to improve survival outcomes of patients.

Abstract 5539: Nivolumab after cyclophosphamide and doxorubicin induction therapy in previously treated advanced non-squamousl non-small cell lung cancer with PD-L1&lt;10%

Purpose: Immune checkpoint inhibitor(ICI) therapies are a standard treatment for advanced non-small-cell lung cancer(NSCLC). However, the beneficial effects are limited to a small subset of patients. Primary resistance to ICIs has been attributed to various kinds of suppressive immune regulatory cells in tumor-microenvironment. Different strategies have thus been explored to escape from immune evasion by depleting and/or inactivating these regulatory cells. Given the immune-modulating effects of low doses of cyclophosphamide and adriamycin (CA), we assessed the efficacy of CA induction therapy to modulate the antitumor effect of the nivolumab in advanced NSCLC.

Methods: This was a single center, open-label, single arm, phase II trial of nivolumab after CA induction therapy in previously treated advanced non-squamous NSCLC with PD-L1&lt;10%. Patients received cyclophosphamide(500mg/m2) and doxorubicin(50mg/m2) every 3weeks with additional nivolumab 360mg from the start of second cycle. After 4 cycles of induction therapy nivolumab 480mg was administered every 4weeks until disease progression or unacceptable toxicity. Assessments were performed every 4 weeks. The primary end point was objective response rate (ORR); secondary end points were progression-free survival (PFS), overall survival(OS) and safety. Level of various immune cells including myeloid-derived suppressor cells (MDSC), cytotoxic CD8+T-cell and regulatory T cells were measured by flow cytometry.

Results: A total of 22 patients were enrolled; the median age, 61 years old; female, 81%; adenocarcinoma histology, 76.2%; and current or former smoker, 26.9%. The ORR and disease control rate (DCR) were 9.1% (95% confidence interval [CI], 1.9 -26.1)) and 22.7% (95% CI, 9.2-42.9) respectively. The median PFS and OS were 2.4 months (95% CI, 1.3-3.5) and 11.6 months (95% CI, 5.3-18.0) respectively. Though there were no significant safety signals during the trial, 72% of patients had grade 3 or 4 hematologic toxicities including neutropenia and anemia during CA combination. Regarding MDSC (HLA-DR-Lin-CD11b+CD33+) level, two patients with good response correlatively maintained the low ratio (&lt;1) of MDSC to CD8+T-cell throughout the treatment.

Conclusions: Our study didn’t meet the primary endpoint. However, CA induction prior to nivolumab showed an immune-modulating potential by decreasing MDSC in two responders. Further augmentation studies for enhancing ICIs response are warranted. As more patients gets ICIs, combination strategy with various immune modulator harbors great potential to eliminate the immunosuppressive mechanism within the tumor microenvironment architecture.

Citation Format: Beung-Chul Ahn, Hyae Young Kim, Geon Kook Lee, Sang-Jin Lee, Ji-Eun Hwang, Kyoungsuk Kwon, Youngjoo Lee, Ji-Youn Han. Nivolumab after cyclophosphamide and doxorubicin induction therapy in previously treated advanced non-squamousl non-small cell lung cancer with PD-L1&lt;10% [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 5539.

Incorporation of SKI-G-801, a Novel AXL Inhibitor, With Anti-PD-1 Plus Chemotherapy Improves Anti-Tumor Activity and Survival by Enhancing T Cell Immunity

A recently developed treatment strategy for lung cancer that combines immune checkpoint inhibitors with chemotherapy has been applied as a standard treatment for lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC), and it has improved the outcomes of chemotherapy. Maintenance treatment with anti-PD-1 antibody (aPD-1) enhances the effect of immunochemical combination therapy and improves therapeutic efficacy, which contributes toward a significant improvement in patient survival rates. The AXL receptor tyrosine kinase (AXL), which is expressed in tumor cells, plays an essential role in the resistance of cancers to chemotherapy and immunotherapy, and stimulates signaling associated with epithelial-mesenchymal transition (EMT) in metastatic cancer. AXL is thus an attractive target for controlling resistance to anti-tumor therapies. In this study, we examined the effect of AXL inhibitors on immune activation and tumor growth in TC1 and C3PQ mouse tumor models, in the context of clinical immunotherapy/chemotherapy and maintenance treatment, using an aPD-1 with/without pemetrexed. To determine the optimal timing for administration of SKI-G-801, an AXL inhibitor, we investigated its anti-tumor effects based on inclusion at the immunochemotherapy and maintenance therapy stages. We also performed flow cytometry-based immune profiling of myeloid cells and lymphoid cells at different points in the treatment schedule, to investigate the immune activation and anti-tumor effects of the AXL inhibitor. The addition of SKI-G-801 to the immune checkpoint inhibitor and chemotherapy stage, as well as the maintenance therapy stage, produced the best anti-tumor results, and significant tumor growth inhibition was observed in both the TC1 and C3PQ models. Both models also exhibited increased proportion of effector memory helper T cells and increased expression of CD86⁺ macrophages. Especially, regulatory T cells were significantly reduced in the TC1 tumor model and there was an increase in central memory cytotoxic T cell infiltration and an increased proportion of macrophages with high CD80 expression in the C3PQ tumor model. These results suggest increased infiltration of T cells, consistent with previous studies using AXL inhibitors. It is expected that the results from this study will serve as a stepping stone for clinical research to improve the existing standard of care.

Predicting treatment outcomes using 18F-FDG PET biomarkers in patients with non-small-cell lung cancer receiving chemoimmunotherapy

Background

Predictive markers for treatment response and survival outcome have not been identified in patients with advanced non-small-cell lung cancer (NSCLC) receiving chemoimmunotherapy. We aimed to evaluate whether imaging biomarkers of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) and routinely assessed clinico-laboratory values were associated with clinical outcomes in patients with advanced NSCLC receiving pembrolizumab plus platinum-doublet chemotherapy as a first-line treatment.

Methods

We retrospectively enrolled 52 patients with advanced NSCLC who underwent baseline ¹⁸F-FDG PET/CT before treatment initiation. PET/CT parameters and clinico-laboratory variables, constituting the prognostic immunotherapy scoring system, were collected. Optimal cut-off values for PET/CT parameters were determined using the maximized log-rank test for progression-free survival (PFS). A multivariate prediction model was developed based on Cox models for PFS, and a scoring system was established based on hazard ratios of the predictive factors.

Results

During the median follow-up period of 16.7 months (95% confidence interval: 15.7-17.7 months), 43 (82.7%) and 31 (59.6%) patients experienced disease progression and death, respectively. Objective response was observed in 23 (44.2%) patients. In the multivariate analysis, maximum standardized uptake value, metabolic tumour volume_2.5, total lesion glycolysis_2.5, and bone marrow-to-liver uptake ratio from the PET/CT variables and neutrophil-to-lymphocyte ratio (NLR) from the clinico-laboratory variables were independently associated with PFS. The scoring system based on these independent predictive variables significantly predicted the treatment response, PFS, and overall survival.

Conclusion

PET/CT variables and NLR were useful biomarkers for predicting outcomes of patients with NSCLC receiving pembrolizumab and chemotherapy as a first-line treatment, suggesting their potential as effective markers for combined PD-1 blockade and chemotherapy.

SKI-G-801, an AXL kinase inhibitor, blocks metastasis through inducing anti-tumor immune responses and potentiates anti-PD-1 therapy in mouse cancer models

Objectives

AXL‐mediated activation of aberrant tyrosine kinase drives various oncogenic processes and facilitates an immunosuppressive microenvironment. We evaluated the anti‐tumor and anti‐metastatic activities of SKI‐G‐801, a small‐molecule inhibitor of AXL, alone and in combination with anti‐PD‐1 therapy.

Methods

In vitro pAXL inhibition by SKI‐G‐801 was performed in both human and mouse cancer cell lines. Immunocompetent mouse models of tumor were established to measure anti‐metastatic potential of SKI‐G‐801. Furthermore, SKI‐G‐801, anti‐PD‐1 or their combination was administered as an adjuvant or neoadjuvant in the 4T1 tumor model to assess their potential for clinical application.

Results

SKI‐G‐801 robustly inhibited pAXL expression in various cell lines. SKI‐G‐801 alone or in combination with anti‐PD‐1 potently inhibited metastasis in B16F10 melanoma, CT26 colon and 4T1 breast models. SKI‐G‐801 inhibited the growth of B16F10 and 4T1 tumor‐bearing mice but not immune‐deficient mice. An antibody depletion assay revealed that CD8⁺ T cells significantly contributed to SKI‐G‐801‐mediated survival. Anti‐PD‐1 and combination group were observed the increased CD8⁺Ki67⁺ and effector T cells and M1 macrophage and decreased M2 macrophage, and granulocytic myeloid‐derived suppressor cell (G‐MDSC) compared to the control group. The neoadjuvant combination of SKI‐G‐801 and anti‐PD‐1 therapy achieved superior survival benefits by inducing more profound T‐cell responses in the 4T1 syngeneic mouse model.

Conclusion

SKI‐G‐801 significantly suppressed tumor metastasis and growth by enhancing anti‐tumor immune responses. Our results suggest that SKI‐G‐801 has the potential to overcome anti‐PD‐1 therapy resistance and allow more patients to benefit from anti‐PD‐1 therapy.

Efficacy and safety of atezolizumab, in combination with etoposide and carboplatin regimen, in the first-line treatment of extensive-stage small-cell lung cancer: a single-center experience

BACKGROUND

Patients with small-cell lung cancer (SCLC) have a dismal prognosis with limited overall survival (OS) despite a high response rate to chemotherapy. Recently, immune checkpoint inhibitors, combined with chemotherapy, as the first-line treatment for extensive-stage (ES)-SCLC have shown improvement in clinical outcomes.

PATIENTS AND METHODS

Real-world data from 68 Korean ES-SCLC patients, treated with atezolizumab, etoposide, and carboplatin at Yonsei Cancer Center between June 2019 and November 2020, were retrospectively analyzed to determine safety and efficacy using Cox regression analysis.

RESULTS

The median follow-up was 11.6 months. The median progression-free survival was 4.6 months (95% confidence interval [CI] 4.0-5.2), and the median OS was 12.0 months (95% CI 7.4-16.6). Baseline bone metastasis, immune-related adverse events (IRAEs), and elevated LDH were related to OS (hazard ratio 2.18, 0.33, and 4.64; P = 0.05, 0.02, and 0.003, respectively). Among the 42 patients with disease progression, liver metastasis progression and baseline bone metastasis were associated with inferior OS, but without statistical significance (hazard ratio 2.47 and 1.97; P = 0.25 and 0.26, respectively). Overall, 61 (89.7%) patients experienced treatment-related adverse events (TRAEs), with hematologic toxicities as the most common grade 3-4 TRAEs. Twenty-two (32.4%) patients experienced IRAEs, with skin rash as the most common, and five (7.4%) patients had grade-3 IRAEs (pneumonitis, hyperglycemia, and aspartate aminotransferase elevation).

CONCLUSION

Atezolizumab, combined with etoposide and carboplatin, showed efficacy and safety in our real-world data. Further studies are needed to predict the response to immunotherapy in SCLC.

A phase II study of poziotinib in patients with recurrent and/or metastatic head and neck squamous cell carcinoma

Background

In phase I studies, poziotinib has shown meaningful efficacy against various types of cancers. This phase 2 study aimed to investigate the efficacy and safety of poziotinib in recurrent and/or metastatic head and neck squamous cell carcinoma (R/M‐HNSCC).

Methods

Overall, 49 patients were enrolled (median age, 62 years; age range, 21–78 years). Patients received a median of two prior treatments including chemotherapy and others and received 12 mg poziotinib orally once daily as part of a 28‐day cycle. The primary endpoint was objective response rate (ORR), and the secondary endpoints were progression‐free survival (PFS) and overall survival (OS). Targeted capture sequencing was performed using available tissues to identify translational biomarkers related to clinical response.

Results

ORR was 22.4%, median PFS was 4.0 months (95% confidence interval [CI], 1.8–6.2 months), and median OS was 7.6 months (95% CI, 4.4–10.8 months). The most common treatment‐related adverse events were acneiform rash (85%) and mucositis (77%). A grade 3 or higher adverse event was acneiform rash (3%). Targeted capture sequencing was performed in 30 tissue samples. TP53 and PIK3CA were the most frequently mutated genes (43%), followed by CCND1 (33%) and EGFR (30%). Mutations in ERBB2, ERBB3, and ERBB4, which are HER family genes, were observed in 17%, 13%, and 10% samples, respectively. There was no difference in the frequency of somatic mutations in the HER family genes between the clinically benefitted and non‐benefitted groups.

Conclusion

Compared to other pan‐HER inhibitors, poziotinib showed clinically meaningful efficacy in heavily treated R/M‐HNSCC.

Clinical trial registration number.

NCT02216916.

Abstract 1471: Incorporation of SKI-G-801, novel AXL inhibitor, with anti-PD-1 inhibitor plus chemotherapy improved anti-tumor activity and survival outcome via enhancing anti-tumor T cell immunity

Background: AXL has been identified to play multiple roles in the tumor microenvironment including the promotion of epithelial-mesenchymal transition and immune evasion. SKI-G-801, a small molecule inhibitor targeting phosphorylation of AXL, presented strong inhibition of cancer migration and invasion. Anti-PD-1(αPD-1) combined with paclitaxel(Pac)/carboplatin(Carbo) and pemetrexed(Pem)/cisplatin(Cis) are standard therapy in non-squamous and squamous lung cancer patients, respectively. Herein, we present that adding AXL inhibition with SKI-G-801 on αPD-1 plus chemotherapy suppressed tumor growth and improved overall survival and also enhanced anti-tumor T cell immunity in both non-squamous and squamous lung cancer models.

Methods: C3PQ squamous and TC-1 non-squamous lung cancer bearing mouse models were established. In C3PQ squamous model, mice were treated with 2 cycles of induction Carbo + Pac + αPD-1 and 13 cycles of maintenance with αPD-1. In TC-1 non-squamous model, mice were treated with 3 cycles of induction with Cis + Pem + αPD-1 and 14 cycles of maintenance therapy. Both models included the groups of SKI-G-801 treatment from induction therapy and/or maintenance therapy. The tumor growth and survival were monitored for 60 days in both models. The tumor infiltrated lymphocytes were analyzed by flow cytometry.

Results: In TC-1 non-squamous model, upfront addition of SKI-G-801 on αPD-1 plus Pem/Cis chemotherapy followed by αPD-1 and Pem maintenance showed the superior overall survival to the others (vs. αPD-1+ Pem/Cis and αPD-1 + Pem maintenance; p&lt;0.001, vs. αPD-1 + Pem/Cis and αPD-1 + Pem + SKI-G-801 maintenance; p&lt;0.01, vs. αPD-1 + Pem/Cis and SKI-G-801 maintenance; p&lt;0.01). In C3PQ squamous model, upfront addition of SKI-G-801 on αPD-1 plus Pac/Carbo followed by αPD-1 prolonged the overall survival compared the others (vs. αPD-1+Pac/Carbo and αPD-1 maintenance; p&lt;0.05, vs. αPD-1 + Pac/Carbo and αPD-1+ SKI-G-801 maintenance; p&lt;0.05, vs. αPD-1 + Pac/Carbo + SKI-G-801 maintenance; n.s.). In line with survival outcomes, upfront SKI-G-801 on αPD-1 combined with chemotherapy showed the strong tumor growth inhibition compared to the others. Especially, effector memory T cells (CD3+CD4+CD44+CD107-) and IFN-γ secretion level of CD8+ T cells were significantly increased in SKI-G-801 treated groups in C3PQ model (p&lt;0.05).

Conclusion: Incorporation of SKI-G-801, a novel AXL inhibitor, with αPD-1 combined with chemotherapy significantly improved overall survival and anti-tumor activity in both non-squamous and squamous lung cancer model through enhancing cytotoxicity of CD8+ T cells and memory CD4+ T cells. These findings provide mechanistic insight into the activity of SKI-G-801 combined with standard therapy and support its clinical development in metastatic NSCLC as first line therapy.

Citation Format: Kyoung-Ho Pyo, Wongeun Lee, Hee Kyu Lee, Dong Kwon Kim, Ha Ni Jo, Chun-Bong Synn, Jae Hwan Kim, Yeongseon Byeon, Young Seob Kim, Beung-Chul Ahn, Min Hee Hong, Sun Min Lim, Byoung Chul Cho, Hye Ryun Kim. Incorporation of SKI-G-801, novel AXL inhibitor, with anti-PD-1 inhibitor plus chemotherapy improved anti-tumor activity and survival outcome via enhancing anti-tumor T cell immunity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1471.

Abstract 1826: Comprehensive preclinical study on GI-101, a novel CD80-IgG4-IL2 variant protein, as a therapeutic antibody candidate with bispecific immuno-oncology target

Introduction: GI-101 was designed to address the significant unmet needs in immunotherapy for noninflamed tumor. The harmonized mechanisms of action consist of the extracellular domain of CD80 acting as a CTLA-4 inhibitor, together with a long-acting IL-2 variant that preferentially binds to the IL2Rβ. Therefore, GI-101 can play a role in the activation of cytotoxic immune cells and inhibition of CTLA-4-B7.1 axis-based immune suppression.

Methods: The binding affinity of GI-101 to IL-2Rs, CTLA-4, and CD28 was performed by SPR and immune cell proliferation was analyzed by CFSE assay in vitro. GI-101 induced dose-dependent pharmacodynamics effects with consistent magnitude following repeat administration in monkeys. Direct anti-tumor effect of GI-101 was tested by single or combination treatment manner in multiple syngeneic and humanized models. Immune profiling in TME was analyzed by flow cytometry, IHC and IFN-γ ELISPOT assay. To mimic the standard care (SOC) in clinic, TC1 lung cancer model was involved in evaluating the efficacy of both 1st line and maintenance therapy of GI-101 with or without immuno-chemotherapy (Cisplatin, Pemetrexed, and anti-PD-1).

Results: CD80 of GI-101 highly binds to CTLA-4 (Kd, 2.9nM), acting as a decoy ligand. IL-2 variant induces CD8+ T and NK cell proliferation. However, GI-101 had no evidence of toxicity related to IL-2 activity in the non-GLP monkey study, including vascular leakage syndrome and cytokine storm. GI-101 elicits improved restoration of immune functions in human PBMCs co-cultured setting with PD-L1/CTLA-4 co-expressed tumor cells. A dose-dependent (3 to 12 mg/kg) single inhibition of tumor growth was observed in CT26 syngeneic model. Immune profiling revealed a robust increase of M1 macrophages, CD8+ central memory T (Tcm) and NK cells but not Tregs in TME. Splenocyte tumor-specific immune cells were strongly proliferated when stimulated with CT26 neoantigens (gp70). IFN-γ+ T cells were significantly increased in draining lymph nodes from GI-101 treated mice. Furthermore, GI-101 was superior at inhibiting tumor growth when co-treated with anti-PD-1 in syngeneic (MC38, TC1, and B16F10) and MDA-MB-231 humanized mice models. Finally, the combination of GI-101 and immuno-chemotherapy showed not only suppressed tumor growth but also improved survival compared to immuno-chemotherapy alone.

Conclusion: The complementary modes of action of GI-101 via checkpoint blockade and IL-2 activity to enhance the proliferation and activation of Tcm and NK cells are projected to translate into superior clinical efficacy and safety as indicated even in ‘cold tumor' models. GI-101 has promising potential to replace the first-generation ICBs as a monotherapy or in combination with other immunotherapies. Our findings provide a rationale for further clinical investigations.

Citation Format: Kyoung-Ho Pyo, Young Jun Koh, Chun-Bong Synn, Jae Hwan Kim, Youngseon Byeon, Ha Ni Jo, Young Seob Kim, Wongeun Lee, Do Hee Kim, Seul Lee, Dong Kwon Kim, Eun ji Lee, Beung-Chul Ahn, Min Hee Hong, Myoung Ho Jang, Sun Min Lim, Hye Ryun Kim, Su Youn Nam, Byoung Chul Cho. Comprehensive preclinical study on GI-101, a novel CD80-IgG4-IL2 variant protein, as a therapeutic antibody candidate with bispecific immuno-oncology target [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1826.

Abstract 2755: Single-cell RNA sequencing reveals priming professional antigen-presenting macrophages and chemokine expressing T cells in tumor microenvironment by AXL inhibitor, SKI-G-801

The mechanistic investigations have defined that AXL inhibition reprograms the immunological microenvironment leading to increased T cells and antigen-presenting cells. However, previous reports did not clearly demonstrate the linchpin mechanism of anti-tumor effects with AXL inhibitors. It may be possible to elucidate the immunological mechanism of AXL inhibitor based on a comprehensive analysis of cell type-specific transcriptomic changes using scRNA-seq. The human CD34-NSG mice were engrafted LUSC tumor. These mice were divided into four dose groups: Vehicle, SKI-G-801, pembrolizumab, and combination groups. The tumor-associated cells were collected for flow cytometry and scRNA-seq analysis, and FFPE sample of tumor tissue was analyzed by a multispectral imager. The combination group demonstrated the superior anti-cancer efficacy to vehicle, pembrolizumab, and SKI-G-801 groups (all p&lt;0.05). The scRNA-seq was performed with Seurat 4.0. The cells were separated into total 9 clusters. Following SKI-G-801 treatment, the T cells showed higher expressions of CD2, CCL5, CCL4, GZMA, and GZMB compared to both pembrolizumab and vehicle groups (both p&lt;0.05). The gene expressions of CD2 and GZMA were higher than pembrolizumab and vehicle groups (both p&lt;0.05). The CDR3 length differences of TCRs and diversity of T cell clones were higher increased in SKI-G-801, pembrolizumab and combination groups than vehicle group (p&lt;0.05). In the macrophage cluster, the HLA-A, HLA-DRA, HLA-DRB1, and IL-1B genes were commonly expressed in SKI-G-801 and combination group (p&lt;0.05). Mostly, the professional antigen-presenting macrophages (MHC class 2 protein complex high, p&lt;0.05) were increased in the combination group. The combination effects between pembrolizumab and SKI-G-801 can be addressed by enhanced antigen presenting machinery, T cell activation and unique T cell clones. These transcriptomic results were highly correlated with the results of multispectral imaging and flow cytometry. Tumor infiltrations of helper T cells and cytotoxic T cells significantly increased in combination and SKI-G-801 groups (p &lt; 0.01, p &lt; 0.001 respectively). In multiplex IHC analysis, the proportion of CD4+ and CD8+ T cells were significantly increased in the tumor nest (both p&lt;0.05), but the Tregs were not changed in the tumor nest which observations were validated by further flow cytometry analysis. A novel AXL inhibitor, SKI-G-801 drives priming of professional antigen-presenting cells and tumor-infiltrating T cells, leading to immunological synapsis for tumor killing, which is significantly enhanced by the combination with pembrolizumab. These results suggest the inhibition of AXL signal pathway by SKI-G-801 could confer a solid rationale for clinical investigation of lung cancer cells.

Citation Format: Kyung-Ho Pyo, Hee Kyu Lee, Ha Ni Jo, Wongeun Lee, Seong Gu Heo, Sang Bin Lim, Dong Kwon Kim, Chun-Bong Synn, Youngseon Byeon, Young Seob Kim, Beung-Chul Ahn, Min Hee Hong, Sun Min Lim, Hye Ryun Kim, Byoung Chul Cho. Single-cell RNA sequencing reveals priming professional antigen-presenting macrophages and chemokine expressing T cells in tumor microenvironment by AXL inhibitor, SKI-G-801 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2755.

Prognostic implications of PD-L1 expression in patients with angiosarcoma

Aim:

There are limited data on the feasibility of programmed death ligand-1 (PD-L1) expression as a prognostic biomarker in metastatic angiosarcoma.

Patients & methods:

We retrospectively collected and analyzed the data on PD-L1 expression in 70 angiosarcoma patients who were diagnosed at our center between 2005 and 2019.

Results:

Thirteen (19%) patients had PD-L1 expression. Metastatic angiosarcoma patients who were PD-L1-negative (n = 24) showed longer median progression-free survival (4.9 vs 1.6 months; p = 0.04) and median overall survival (OS; 10.9 vs 5.4 months; p = 0.01) than those who were PD-L1-positive (n = 4). PD-L1 status proved to be a significant factor for OS.

Conclusion:

Metastatic angiosarcoma patients with PD-L1 expression showed shorter survival. PD-L1 status is an independent prognostic factor for OS in metastatic angiosarcoma patients.

Angiosarcoma, a rare subtype of sarcoma, is highly aggressive and has poor prognosis. The majority of patients are diagnosed at advanced and metastatic stages, and treatment options for these subsets of patients are limited to cytotoxic chemotherapy. Validation of prognostic markers including PD-L1 expression remain to be fully carried out in metastatic angiosarcoma. In our study, we assessed the PD-L1 expression in metastatic angiosarcoma and its role as a prognostic biomarker.

Dynamic changes in circulating PD-1+CD8+ T lymphocytes for predicting treatment response to PD-1 blockade in patients with non-small-cell lung cancer

BACKGROUND

The predictive value of immune monitoring with circulating CD8⁺ T lymphocytes for treatment response to programmed cell death protein 1 (PD-1) inhibitors has not been explored in non-small-cell lung cancer (NSCLC), prompting us to investigate whether dynamic changes in PD-1⁺CD8⁺ T lymphocytes have predictive value for durable clinical benefit (DCB) and survival after PD-1 blockade.

METHODS

Patients with recurrent and/or metastatic NSCLC treated with PD-1 inhibitors were enrolled (discovery cohort; n = 94). Peripheral blood was obtained immediately before and after one cycle of treatment with PD-1 blockade. Phenotyping of circulating CD8⁺ T lymphocytes was conducted using multi-colour flow cytometry. Predictive values of dynamic changes in circulating PD-1⁺CD8⁺ T lymphocytes during the first cycle were validated in an independent cohort (validation cohort; n = 54) of a prospective trial with a PD-1 inhibitor (NCT03486119).

RESULTS

Circulating PD-1⁺CD8⁺ T lymphocytes were enriched with effector/memory populations with elevated expression of activation- and exhaustion-related markers. Reduction in the frequency of PD-1⁺ cells among CD8⁺ T lymphocytes after one cycle of treatment was associated with a higher probability of DCB and superior survival outcomes in the discovery cohort. Similar results were obtained in the analysis of tumour antigen NY-ESO-1-specific CD8⁺ T lymphocytes and the validation cohort. Mechanistically, PD-1 molecule expression on CD8⁺ T lymphocytes suppresses the effector functions of tumour antigen-specific CD8⁺ T lymphocytes.

CONCLUSIONS

Dynamic changes in circulating PD-1⁺CD8⁺ T lymphocytes predict clinical, and survival benefit from PD-1 blockade treatment in NSCLC, providing a useful tool to identify patient subgroups who will optimally benefit from PD-1 inhibitors.

Abstract 3325: Intratumoral STING activation on artificially generated cutaneous metastasis of EML4-ALK lung cancer alters immunologic milieu of primary tumor

Introduction: Therapeutic monoclonal antibodies targeting immune checkpoints inhibitors (ICIs) are game changers in the treatment landscape of multiple solid tumors. However, response rate remains relatively low in most cases. Particularly, anti-PD-1 or PD-L1 therapies are not effective in EML4-ALK rearranged- and EGFR mutant-NSCLC patients due to their cold immune microenvironment. Recently, activation of stimulator of interferon genes (STING) has shown potential to enhance antitumor immunity through induction of various pro-inflammatory cytokines and chemokines. In this study, we attempted to induce inflamed tumor microenvironment by artificially generating skin metastasis using intratumoral STING activation in EML4-ALK transgenic mice.

Methods: EML4-ALK transgenic mice were implanted with a new EML4-ALK tumor subcutaneously. The size of lung primary tumor and subcutaneous tumor were each measured by micro-MRI and calipers, respectively. The treatment groups were divided into the control group, tumor-implanted group, and intratumor STING activation group (skin). On day 14, subcutaneous tumor, primary tumor (lung), and systemic immune organs were collected for further analysis.

Results: STING agonist promotes pIRF3 signaling and massive immune cell recruitment in skin region, the subcutaneous tumor was dramatically reduced with hyperinflammation. In addition, primary tumor (lung) was observed with increased T cell population in tumor with necrotic regions. IFN-gamma expression was increased in bronchoalveolar fluid in STING activation group compared to control and tumor only groups (P &lt; 0.05). Tumor macrophages and NK cells were increased compared to control group (P &lt; 0.05, P = ns, respectively). We considered that skin consists of cutaneous innate immune cells, especially, macrophage. Increased T cells and macrophages were observed in STING activated tumor within 6 hours. The in vitro assay proved that macrophages highly express chemokines (CCL5, CCL2, and CCL12) which is recruiting T cells and myeloid cells. This initial immune activation results in increased tumor-specific T cell, especially, memory helper T cell (CD3+CD4+CD44+) in spleen, LN and MLN. We tested anti-IFN-beta antibody for neutralization of STING activity in vivo. The IFN-gamma expression of lymphocytes in MLN was reduced but not significant.

Conclusion: This study confirmed that STING activation in cold tumor alters inflamed-immunologic milieu of primary tumor via hyper cutaneous immune activity with pivotal roles of macrophage. Our findings provide a rationale for further clinical investigations.

Keywords: STING, cutaneous metastasis, EML4-ALK

Citation Format: Chun-Bong Synn, Ji Min Lee, SunMin Lim, Do Hee Kim, Bianca-Ioana Gheorghiu, Jae-Hwan Kim, Wongeun Lee, Sung-Eun Kim, Sungwon Park, Beung-Chul Ahn, Ha Ni Jo, Min Hee Hong, Hye Ryun Kim, Kyoung-Ho Pyo, Byung Chul Cho. Intratumoral STING activation on artificially generated cutaneous metastasis of EML4-ALK lung cancer alters immunologic milieu of primary tumor [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 3325.

Abstract 4981: Comprehensive analysis of immune phenotypes identifies CD73+ CD163high macrophages as a prognostic biomarker in lung adenocarcinoma

To better understand the immune profile within the tumor microenvironment (TME) and the potential immune-evasion capacity that may arise from administration of immune checkpoint inhibitors, we investigated immunological phenotypes and their correlations with genomic alterations in order to provide predictive/prognostic implications in lung adenocarcinoma (LAC).Surgical sections with corresponding peripheral blood mononuclear cells were collected from 76 patients with pathologically confirmed Ia-IIIa. The histological contents expressing immune checkpoint molecules in the tumor nest and stromal area were imaged and quantified using a multi-spectral imaging system. Distribution of tumor mutation burden (TMB) and non-synonymous somatic mutations were analyzed in whole exome sequencing (WES) data.Total 76 patients consisted of EGFR-mutant (n=37) and EGFR-wild type (n=39) tumors. As is well known, the number of tumor-infiltrating cytotoxic T cells (174.7 ± 24.4 cells/mm2) and TMB (3.8 ± 0.4) in EGFR-mutant tumors was significantly lower than those of EGFR wild type tumors (394.2 ± 82.3 cells/mm2 and 6.7 ± 1.2) (p=0.0146 and p=0.0254, respectively), elucidating EGFR mutation-mediated immune evasion. The subjects carrying EGFR wild-type were classified into two subgroups by the density of tumor-infiltrating cytotoxic T cells, defined as the high TIL (n=20) and low TIL (n=19). There was great difference of mean density of cytotoxic T cells between low TIL group (129.6 ± 16.8 cells/mm2) and high TIL group (672.8±143.5 cells/mm2). Tumor-infiltrating T cells were granzyme B-positive, suggesting most cells were tumor-specific. Interestingly, no significant difference in TMB was found between the two subgroups (7.5 ± 1.9 in low TIL group vs. 5.8±1.3 in high TIL group; p=0.4642). Tumor proportion score (TPS) of PD-L1 was remarkably higher in high TIL group than low TIL group (29.7 ± 6.5% vs. 13.9 ± 2.8%, p=0.0008, respectively), but no significant differences of tumoral CD73 and IDO between the two groups (p=0.643 and p=0.923, respectively). Even there were no significant differences in counts of tumor-infiltrating macrophages in all types of macrophage, significantly higher counts of PD-L1+ M1-type macrophages (CD68+ CD163low) in the stromal area were discovered in the high TIL group compared to those of the low TIL group (396.2 ± 93.6 vs. 139.8 ± 30.1, p=0.0114, respectively), indicating that most of macrophages resided in the stromal area. Interestingly, the low TIL group exhibited higher counts of CD73+ M2-type macrophages (CD68+ CD163high) in the stromal area than the high TIL group (644.5 ± 110.9 vs. 387.9 ± 73.2, p=0.0639, respectively). Cell count ratio (M1/M2) of macrophages was significantly higher in the high TIL group (p=0.0042), suggesting that the TME with a smaller number of TILs tends to contain more M2-type macrophages. The tumor recurrence was more frequent in the low TIL group compared to the high TIL group with no statistical significance (p=0.127). In surgically resected lung adenocarcinoma patients, the subgroup with a low density of tumor-infiltrating cytotoxic T cells had a large number of CD73+ M2-type macrophages, which may contribute to poor prognosis.

Acknowledgement: This study was sponsored by Ono Pharma Co., Ltd

Citation Format: Jae-Hwan Kim, Tae-Min Kim, Sung-Gu Her, Kyoung-Ho Pyo, Jeong- Oh Kim, Beung-Chul Ahn, Byoung Chul Cho, Jin Hyoung Kang. Comprehensive analysis of immune phenotypes identifies CD73+ CD163high macrophages as a prognostic biomarker in lung adenocarcinoma [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 4981.

Abstract 5189: Neoadjuvant and adjuvant anti-PD-1 based combination immunotherapy with a novel AXL inhibitor, SKI-G-801 in syngeneic tumor model: A combined analysis of immune profiling

Introduction: Neoadjuvant therapy suggests the systemic treatment of cancer prior to surgical therapy. The main purpose of neoadjuvant therapy is to improve surgical outcomes in patients for whom a primary surgical approach is difficult to practice. Recently, Anti-PD-1 has been applied to neoadjuvant and adjuvant therapy, but the anti-cancer responses are not sufficient to prevent tumor recurrence. According to our previous study, a novel AXL inhibitor, SKI-G-801 strongly inhibits metastasis of syngeneic tumor with immune responses. The primary goal of this study is to overcome limitation of anti-PD-1 based neoadjuvant and adjuvant therapy with SKI-G-801.

Methods: 4T1 cancer bearing mouse models were established for neoadjuvant or adjuvant treatment. Mice were treated with single anti-PD-1 (BIW), SKI-G-801 (QD) or a combination for 6 days, followed by the surgical dissection of tumor tissue in a subcutaneous xenograft model. In five mice per group, their survival rates were monitored for 50 days. We used flow cytometry and immunohistochemistry for comprehensive immune profiling and tumor-infiltrating lymphocytes (TILs) from three mice per group surgically removed tumor tissues. Three tumors per group were stained, and CD3-positive cells per unit area (mm2) were analyzed using Vectra Polaris.

Results: According to results, the median survival of control group (only surgical operation without treatment) was 16 days (N=5), whereas, the longest survival group was neoadjuvant-combination (median survival = 37 days). Two out of five mice were survived until end of experiment (D-50). Most of the groups had similar outcomes excluding neoadjuvant-combination group. The median survival of adjuvant-anti-PD-1 group was 30 days, and adjuvant-SKI-G-801 and neoadjuvant-anti-PD-1 group were 25 days. The Neoadjuvant-SKI-G-801 was recorded 23.5 days. Statistically, survival rate of neoadjuvant-combination therapy was significantly higher than of neoadjuvant-anti-PD-1 and neoadjuvant-SKI-G-801 (log-rank test, p &lt;0.01).The reason for neoadjuvant therapy is to improve immune responses before surgical operation. We investigated the effects of SKI-G-801 or anti-PD-1 alone and combination therapy on neoadjuvant treatment in the tumor microenvironment. IHC and flow cytometry were performed to elucidate tumor infiltrating immune cell populations with the tumor obtained by surgery. In IHC result, CD3+ cells population was significantly increased in SKI-G-801 alone and combination of neoadjuvant therapy compared to control group (p&lt;0.05, p &lt; 0.001, respectively), however, anti-PD-1 group was not significant. IFN-γ+ Tc cells, CD3+CD44+ memory Tc, and PD-1+Tc cells were significantly infiltrated into the tumor in the combination of neoadjuvant therapy (p &lt; 0.01).

Conclusion: This study confirmed that a potential combination with aPD-1 and SKI-G-801 applies to neoadjuvant therapy, as evidenced by increased T cell infiltration and function. Our findings provide a rationale for further clinical investigations.

Keywords: Axl inhibitor, Neoadjuvant therapy, Adjuvant therapy, Immunotherapy, Anti-PD-1

Citation Format: Ha Ni Jo, Wongeun Lee, Chun-Bong Synn, Hee Kyu Lee, Jae-Hwan Kim, Yeongseon Byeon, Sung Eun Kim, Ji Min Lee, Do Hee Kim, Jung-Ho Kim, Beung-Chul Ahn, Min Hee Hong, Hye Ryun Kim, Kyoung-Ho Pyo, Byoung Chul Cho. Neoadjuvant and adjuvant anti-PD-1 based combination immunotherapy with a novel AXL inhibitor, SKI-G-801 in syngeneic tumor model: A combined analysis of immune profiling [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 5189.

Abstract B16: High-resolution metagenomic profiling revealed gut microbiome features for the response to cancer immunotherapy reproducible among multiple cohorts of patients

Cancer immunotherapy is currently standard of treatment showing significant clinical benefits to cancer patients, but the beneficial effects are limited to a relatively small subset of patients. Of various factors that may affect the efficacy of cancer immunotherapy, the gut microbiome is receiving more attention because of its strong correlation with immune regulation. Recently, independent studies based on Western populations have identified several taxa that are differentially abundant between responders and nonresponders. However, the reported taxa associated with anti-PD-1 response differ entirely among these studies. In this study, we performed 1) deep (&gt;100M reads in average) metagenome shotgun sequencing on the fecal sample of 49 Korean non-small cell lung cancer (NSCLC) patients, 2) taxonomic profiling using a highly comprehensive gut microbiome-specific genome database, and 3) gene-level profiling with the gut microbiome specific gene catalog to improve the resolution of metagenomic analysis. With the high-resolution metagenomic profiling, we found several taxonomic and functional signatures associated with the response of anti-PD-1 therapy. Interestingly, we found that some of the signatures were reproduced in five independent datasets regardless of the cancer types (melanoma, NSCLC, and renal cell carcinoma) and the type of immunotherapy (anti-PD-1, anti-CTLA4, and the combination of them). For instance, a responder-enriched taxon in the Korean cohort was more frequently detected in the responders in all cohorts (abundance fold-change &gt; 2) and significantly enriched (p&lt;0.05) in two cohorts. Moreover, when we performed an association analysis with the combined profile, the taxon was identified with the highest significance among the differentially abundant taxa (fold-change=2.41, p=2.5e-06). Consistent with the result of the taxon-level analysis, we found that the genes encoded by the taxon were also enriched in responders in multiple studies. In summary, using high-resolution metagenomic profiling, we identified gut microbiome features for the response to cancer immunotherapy shared across multiple cohorts for the first time, to the best of our knowledge.

Citation Format: Chan Yeong Kim, Beung-Chul Ahn, Min Hee Hong, Yoo Jin Chun, Hye Ryun Kim, Insuk Lee. High-resolution metagenomic profiling revealed gut microbiome features for the response to cancer immunotherapy reproducible among multiple cohorts of patients [abstract]. In: Proceedings of the AACR Special Conference on the Microbiome, Viruses, and Cancer; 2020 Feb 21-24; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2020;80(8 Suppl):Abstract nr B16.

Abstract 683: A machine learning based clinical decision support system (CDSS) for anti-PD-1 therapy using non-invasive blood marker and clinical information for lung cancer patients

Cancer immunotherapy with anti-PD-1 therapy (αPD-1) has greatly improved the survival outcome of patients with non-small cell lung cancer (NSCLC). However, the response rates of αPD-1 are around 20-30% based on clinical trials. The presence of PD-L1, tumor infiltrating lymphocyte or tumor mutation burden may be used as indicators of response, but are still limited to predict αPD-1 response. In this study, we established the machine learning based clinical decision support system (CDSS) to predict the αPD-1 response by comprehensively combining clinical information and blood-based data which are easily assessable in routine practice.We enrolled 126 patients with NSCLC treated with the αPD-1 at Yonsei cancer center. Clinical data including patient characteristics, mutation, treatment outcomes, and adverse events were collected and analyzed. Forty patients additionally had blood-based immune data by flow cytometry. There were two data sets; clinical data set (n=126) with 15 variables, and immune data set (n=40) with 37 variables. We found that 27 variables out of 52 variables are selected by recursive feature elimination. The responders are defined as PR or SD ≥6 months and the non-responders are defined as the others. Supervised learning algorithms such as the LASSO, Ridge, Elastic Net, SVM, ANN, and RF were applied to each data set for predicting the αPD-1 response. The performances of each model were evaluated according to the ROC curve or cross-validation errors. Variable importance was measured by using the random forest and gradient boosting.Patient characteristics included male (69.8%), age ≥ 60 years (66.2%), ECOG 0/1 (77.7%), adenocarcinoma (69.8%), EGFR mutations (15.1%), and PD-L1 positive (61.2%). We classified the patients into responders (38%) and non-responders (62%) in total 126 patients. A result from the clinical data set of 126 patients demonstrated that the Ridge regression model (AUC: 0.78) can more accurately predict the αPD-1 response than others. Of 15 clinical variables, some are considered to be important in the following order; tumor burden,age, PD-L1, ECOG PS, and irAE based on the random forest. When we performed the machine learning process with clinical and immune data, The Ridge regression model (AUC:0.82) showed the good performance to predict αPD-1 response, compared to the single clinical model. The machine learning based CDSS for aPD-1 to NSCLC patients has benefit for predicting aPD-1 responses. Our prediction model could be easily accessible and fast processed in routine practice. The supervised machine learning based non-invasive predictive score (NIPS) demonstrates the rate of aPD-1 response on NSCLC patients. We will validate NIPS in independent patient cohort and currently are establishing the NIPS as web-based software.

Citation Format: Kyoung-Ho Pyo, Beung-Chul Ahn, Chun-Feng Xin, Dongmin Jung, Chang Gon Kim, Min Hee Hong, Byoung Chul Cho, Hye Ryun Kim. A machine learning based clinical decision support system (CDSS) for anti-PD-1 therapy using non-invasive blood marker and clinical information for lung cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 683.

Comprehensive analysis of the characteristics and treatment outcomes of patients with non-small cell lung cancer treated with anti-PD-1 therapy in real-world practice

Purpose

Immune checkpoint inhibitors (ICI) have shown marked responses in patients with non-small cell lung cancer (NSCLC) in clinical trials. However, because such trials comprise cohorts selected based on specific criteria, it is unclear if their results represent routine clinical practice.

Methods

We examined 155 patients with advanced NSCLC who were administered either nivolumab or pembrolizumab at Yonsei Cancer Center, Korea between March 2014 and January 2019. Patient characteristics, EGFR/ALK mutation status, metastatic locations, response to ICIs, and adverse events were retrospectively analyzed.

Results

The median age was 64 years and 72.9% of patients were male; former or current smokers constituted 67.1% of the subjects. Adenocarcinoma was predominant (67.7%), and 50.3% of the patients underwent ≥ 2 previous treatments. Twenty-three patients (14.8%) were EGFR mutation- or ALK rearrangement-positive. The objective response rate (ORR) was 23.9% [95% confidence interval (CI) 17.4–31.4%]; the median progression-free survival (PFS) and overall survival (OS) were 3.06 (95% CI 1.893–4.21) and 10.25 (95% CI 5.39–15.11) months, respectively. Multivariate analysis identified ECOG performance status, EGFR mutation/ALK rearrangement status, liver metastasis and PD-L1 proportion as independent predictors of OS. Furthermore, 61.9% of the patients had adverse events of any grade; 38.1% had immune-related adverse events that were associated with PFS and OS on multivariate analysis.

Conclusions

The real-world ORR, PFS, OS, and adverse event profiles were comparable to previous clinical trials despite the patients’ different baseline characteristics. Our findings can aid in establishing effective immunotherapeutic management of NSCLC in routine clinical practice.

Electronic supplementary material

The online version of this article (10.1007/s00432-019-02899-y) contains supplementary material, which is available to authorized users.

Angiopoietin-1 induces endothelial cell sprouting through the activation of focal adhesion kinase and plasmin secretion

Angiopoietin-1 (Ang1) is a strong inducer of endothelial cell sprouting, which is a first step in both angiogenesis and neovascularization. We examined the mechanisms underlying Ang1-induced cell sprouting using porcine pulmonary artery endothelial cells. Ang1 induced the nondirectional and directional migration of endothelial cells mediated through the Tie2 but not the Tie1 receptor. Ang1 induced tyrosine phosphorylation of p125(FAK), and this phosphorylation was dependent on phosphatidylinositol (PI) 3'-kinase activity. Ang1 induced the secretion of plasmin and matrix metalloproteinase-2 (MMP-2), which is inhibited by PI 3'-kinase inhibitors. Ang1 also induced the secretion of small amounts of proMMP-3 and proMMP-9 but not proMMP-1. Ang1 suppressed the secretion of tissue inhibitor of metalloproteinase-2 (TIMP-2), but not of TIMP-1. Addition of alpha(2)-antiplasmin, a combination of TIMP-1 and TIMP-2, or PI 3'-kinase inhibitors inhibited Ang1-induced sprouting activity. Therefore, Ang1-induced sprouting activity in endothelial cells may be accomplished by cytoskeletal changes and secretion of proteinases and may be largely mediated through intracellular PI 3'-kinase activation.

Intramedullary fat necrosis of multiple bones associated with pancreatitis

We describe findings of intramedullary fat necrosis on five imaging studies in a patient with alcoholic pancreatitis. Radiography and CT of extremities showed multiple osteolytic lesions that were initially considered to be metastases. However, a 99mTc-methylene diphosphonate whole-body bone scan revealed abnormal areas of increased uptake in only the bones of extremities without involvement of the axial skeleton, a distribution quite unusual for metastatic disease. Furthermore, 99mTc-sestamibi scintigraphy was essentially normal. MRI revealed findings compatible with the diagnosis of fat necrosis/infarct. Findings from bone biopsy demonstrated necrotic bone marrow without malignant cells. It may not be necessary to perform all the imaging studies described in this report when clinical features suggesting metastatic fat necrosis are present. Appearance and distribution of abnormalities on the whole-body bone scan and MR images show that necrosis/infarct of the marrow may obviate bone biopsy, which is often needed to confirm the diagnosis of intramedullary fat necrosis and to exclude neoplastic processes.

Sarcomatous transformation of neurofibromas. Comparative imaging with Ga-67, Tl-201, Tc-99m pentavalent DMSA and Tc-99m MIBI

A 29-year-old man, with a history of von Recklinghausen's disease, presented with progressive dyspnea associated with a rapidly growing mass on the right chest wall. Plain radiograph and CT of the chest revealed a huge soft-tissue mass with central low-density area involving the right upper lung and chest wall. SPECT imaging with Ga-67 citrate, Tl-201 chloride, Tc-99m pentavalent DMSA (V-DMSA), and Tc-99m MIBI were performed to characterize the mass. The tumor concentrated Ga-67, Tl-201, and Tc-99m (V) DMSA, but not Tc-99m MIBI. Punch biopsy of the lesion revealed malignant transformation of a thoracic neuroma (neurofibrosarcoma). Subsequently, findings compatible with the presence of a multidrug resistance-1 (MDR1) gene in the tumor was documented, which may explain the poor uptake of Tc-99m MIBI. The patient did not respond to intensive chemotherapeutic regimens, and died 3 months later. This case demonstrates the potential use of combined radionuclide imaging for the detection of malignant transformation of neurofibroma, as well as for predicting tumor response to chemotherapy.

Detection, quantitation, and localization of bovine angiogenin by immunological assays

Bovine angiogenin (bAng) is a potent blood vessel inducing protein found in bovine serum and milk. Antisera have been raised against bAng. Western blot analysis for bAng indicated that the polyclonal antibody recognized bAng specifically, and no cross-reactivity with bovine RNase A, a protein homologous to bAng, was observed. The sandwich enzyme-linked immunosorbent assay for bAng was sensitive to 10 pg of bAng, and this assay was able to quantitate bAng in bovine serum (100-180 ng/mL) and milk (4-8 micrograms/mL). Strong positive immunohistochemical reactions were detected in alveolar cells, the secretion of alveolar cells and excretory ducts in sections of cow mammary gland, epithelial cells of visceral peritoneum and bile-duct in sections of cow liver, and epithelial cells and mucous glands in sections of cow gallbladder. These results suggest that epithelial cells and secretory cells are major sites of angiogenin synthesis.