The impact of cGAS/STING tumor expression on PD-1/L1 inhibitor efficacy and the tumor microenvironment remain to be elucidated. In a post-hoc analysis of a prospective biomarker study with 106 advanced NSCLC patients treated with PD-1/L1 inhibitors from December 2015 to September 2018, tumor tissue before treatment from 68 patients was analyzed. cGAS and STING expression were measured using immunohistochemical staining and H-scores. Additionally, 40 serum proteins were quantified before and 4–6 weeks after treatment initiation. Median cGAS and STING H-scores were 220 (range, 5–300) and 190 (range, 0–300), respectively. There were no differences in cGAS or STING H-scores between the high (tumor proportion score [TPS] ≥ 50) and low (TPS < 50) PD-L1groups (p = 0.990 and 0.283, respectively). Unexpectedly, patients with high cGAS (H-score ≥ 220) demonstrated significantly shorter progression-free survival (PFS) of PD-1/L1 inhibitors when the PD-L1 TPS was high (median PFS: 143 days vs. not reached; p = 0.028); PFS at 18 months was 7% and 53% in the high and low cGAS groups, respectively while STING expression did not impact PFS. In serum protein analyses, high cGAS H-score was associated with significantly higher TGF-β1 and TGF-β2 before PD-1/L1 inhibition (47.5 vs. 22.3 ng/l, p = 0.023; 2118 vs. 882 pg/ml, p = 0.037); additionally, the cGAS H-score significantly correlated with TGF-β1 (r = 0.451, p = 0.009) and TGF-β2 (r = 0.375, p = 0.031) basal levels. cGAS expression, but not STING, predicts poor PD-1/L1 inhibitor efficacy in NSCLC with high PD-L1, potentially due to a TGF-β-mediated immunosuppressive environment (UMIN000024414).
Abstract Background Although predictive value of immune-related adverse events (irAEs) induced by immune checkpoint inhibitors (ICIs) have been suggested by several studies, their assessments were insufficient because patients were categorized only by the occurrence of irAEs. It has not been elucidated whether irAEs also play a significant role even in responders. Materials and Methods Between December 2015 and September 2018, 106 patients with advanced non-small cell lung cancer treated with ICIs were enrolled in our prospective biomarker study. Twenty-three of these were responders, defined as those with complete or partial response. We investigated the proportion of irAEs among overall and responders. For responders, progression-free survival (PFS) and overall survival of ICIs were compared between those with and without irAEs. As an exploratory analysis, we measured 41 proteins from peripheral blood before and after ICI treatment. Results The proportion of irAEs was significantly higher in responders than nonresponders (65.2% vs. 19.3%, p < .01). Among responders, clinical characteristics did not differ regardless of the occurrence of irAEs. However, there was a significant difference in PFS among responders (irAE group 19.1 months vs. non-irAE group 5.6 months; hazard ratio: 0.30 [95% confidence interval: 0.10–0.85]; p = .02). Of 41 protein analyses, fibroblast growth factor-2 at baseline and monocyte chemoattractant protein fold change showed significant differences between them (p < .04). Conclusion Although this is a small sample–sized study, irAE might be a predictive factor of durable efficacy, even in patients who responded to ICIs. Investigation into the significance of irAEs in responders will contribute to the establishment of optimal administration of ICI.
e21048 Background: The cGAS/STING pathway is an innate immune pathway that promotes cytokine production in response to cytoplasmic DNA, and its activation is important for the induction of anti-tumor immunity. However, predictivity of cGAS/STING tumor expression on the efficacy of PD-1/L1 inhibitors and subsequent immune responses (e.g., changes in serum cytokines) remain to be elucidated. Non-small cell lung cancer with PD-L1 tumor proportion score (TPS) of 50% or higher respond well to immune checkpoint inhibitor (ICI) monotherapy, but there is still a poor response group among them, and the extraction of such patients is an urgent issue. Methods: This is a post hoc analysis of prospective biomarker study, which enrolled 106 patients with advanced non-small cell lung cancer (NSCLC) who were treated with ICI monotherapy between December 2015 and September 2018. We investigated in 68 patients with preserved evaluable tissue samples taken before start of ICI treatment. cGAS, STING, and PD-L1 expression in tumors were stained by immunohistochemistry. cGAS and STING were evaluated by H-score. Using peripheral blood which was collected by the observational study, 41 serum proteins at the time of PD-1/L1 inhibitors initiation and in 4 – 6 weeks later were quantified. Results: The median cGAS and STING H-SCORE were 220 (5 – 300) and 190 (0 – 300), respectively. There were no differences in cGAS or STING H-SCORE between PD-L1 high (TPS ≥50) and low (TPS < 50) groups ( p= 0.990 and 0.283). Cases were divided into two groups according to median of the H-SCORE, respectively, and compared. Unexpectedly, cGAS high (H-SCORE ≥220) patients showed significantly shorter progression free survival of ICI when PD-L1 TPS ≥50 (median progression free survival (PFS); 143 days vs. not reached, p = 0.028) and progression free rate at 18 months was 7 and 53%, while no association was observed when PD-L1 TPS < 50 (median PFS; 47 vs. 61 days, p= 0.798). STING tumor expression was not associated with PFS regardless of PD-L1 TPS. In cytokine analysis, cGAS high was associated with significantly higher serum concentrations of TGF-β1 and β2 before ICI initiation (47.5 vs. 22.3hg/l, p= 0.023; 2118 vs. 882rg/ml, p= 0.037), and H-SCORE of cGAS, not STING, were significantly correlated with TGF-β1 and β2 basal levels (r = 0.447, p= 0.009; r = 0.373, p= 0.033). Analysis about fold change from baseline to 4 – 6 weeks later of 41 cytokines revealed that leptin significantly increased in cGAS high tumor while no difference was seen in all of cytokines between STING high and low tumor. Conclusions: Tumor expression (H-Score) of cGAS, not STING, is a candidate for predictor of poor response to ICI monotherapy in NSCLC with PD-L1 high (TPS ≥50). cGAS tumor expression may be associated with TGF-β producing, immune-suppressive tumor microenvironment in NSCLC. Clinical trial information: UMIN000024414.
Background: An association exists among the diagnostic yield of transbronchial biopsy using endobronchial ultrasonography with a guide sheath (EBUS-GS-TBB) and several factors, such as simple within or adjacent endobronchial ultrasonography (EBUS) findings. Here, we aimed to investigate whether more detailed EBUS findings affect the diagnostic yield of lung cancer in EBUS-GS-TBB. Methods: We conducted this retrospective single-center cohort study, enrolling consecutive patients with lung cancer who underwent EBUS-GS-TBB. The primary outcome was examination of predictive factors affecting the diagnostic yield of lung cancer using EBUS-GS-TBB. The secondary outcome was a subgroup analysis of within and adjacent lesions. The adjacent angle was defined as the angle formed by the midpoint of the probe and the two points where the edge of the probe and shadow of the tumor intersected. Results: Of the 179 lesions investigated, 140 (78.2%) were diagnosed using EBUS-GS-TBB. The diagnostic yields of within and adjacent lesions were 91.6% and 51.7%, respectively. In the multivariable analysis, within lesions had significantly higher diagnostic yields than did the adjacent lesions (P<0.001). The adjacent angle was larger in lesions diagnosed using EBUS-GS-TBB than in undiagnosed lesions (P=0.003). In adjacent lesions, the diagnostic yields were 75.0% and 36.1% for lesions ≥180° and <180°, respectively. Conclusions: In adjacent lesions, the diagnostic yields differed significantly depending on the adjacent angle. Even if EBUS findings are adjacent, the operator should identify the branch of the bronchus with a greater adjacent angle. Future studies should investigate improvements in diagnostic yields via additional procedures for lesions with small adjacent angles.
Introduction Triplet regimen of carboplatin or cisplatin with pemetrexed and pembrolizumab is a standard treatment for patients with advanced, chemo-naïve, non-squamous non-small cell lung cancer. However, subgroup analysis for patients aged ≥75 years indicated that elderly patients who received the triplet regimen may have had shorter survival times than if they had chemotherapy alone (HR of 2.09). Treatments in the elderly are not always as effective or safe as for non-elderly patients, so there remains concern over whether the triplet regimen can be widely used in the elderly. Methods and analysis This is a single-arm, prospective, multicentre phase II study. The primary endpoint is set as the overall response rate according to Response Evaluation Criteria in Solid Tumors V.1.1. Secondary endpoints are progression-free survival, disease control rate and safety. This trial will enrol 22 patients. Ethics and dissemination This study was approved by the Wakayama Medical University Central Review Board on 2 December 2019 (approval number: W-32). Patients have been enrolled since February 2020. As the study will complete accrual in January 2022, results will be submitted for publication in peer-reviewed medical journals within 2023 and international scientific meetings. This study will provide significant information on whether the triplet regimens are clinically beneficial to elderly patients. Trial registration number Japan Registry of Clinical Trials (jRCTs051190095).