Tumor Programmed Cell Death Ligand 1 Research Articles

Nivolumab plus chemotherapy or ipilimumab versus chemotherapy in patients with advanced esophageal squamous cell carcinoma (CheckMate 648): 29-month follow-up from a randomized, open-label, phase III trial.

First-line nivolumab plus chemotherapy and nivolumab plus ipilimumab both demonstrated significant overall survival (OS) benefit versus chemotherapy in previously untreated patients with advanced esophageal squamous cell carcinoma (ESCC) in the CheckMate 648 trial, leading to approvals of both nivolumab-containing regimens in many countries. We report longer-term follow-up data. This open-label, phase III trial (NCT03143153) enrolled adults with previously untreated, unresectable, advanced, recurrent, or metastatic ESCC. Patients were randomized 1:1:1 to nivolumab plus chemotherapy, nivolumab plus ipilimumab, or chemotherapy. Primary endpoints were OS and progression-free survival (PFS) by blinded independent central review. Hierarchical testing was performed first in patients with tumor cell programmed death ligand 1 (PD-L1) expression of ≥1% and then in the overall population. A total of 970 patients were randomly assigned. After 29 months of minimum follow-up, nivolumab plus chemotherapy continued to demonstrate improvement in OS versus chemotherapy (hazard ratio [HR] = 0.59 [95% CI: 0.46-0.76]) in patients with tumor cell PD-L1 expression of ≥1% and in the overall population (HR = 0.78 [95% CI: 0.65-0.93]) and with nivolumab plus ipilimumab versus chemotherapy (HR = 0.62 [95% CI: 0.48-0.80]) in patients with tumor cell PD-L1 expression of ≥1% and in the overall population (HR = 0.77 [95% CI: 0.65-0.92]). In patients with tumor cell PD-L1 expression of ≥1%, nivolumab plus chemotherapy demonstrated PFS benefit versus chemotherapy (HR = 0.67 [95% CI: 0.51-0.89]); PFS benefit was not observed with nivolumab plus ipilimumab versus chemotherapy (HR = 1.04 [95% CI: 0.79-1.36]). Among all treated patients (n = 936), Grade 3-4 treatment-related adverse events were reported in 151 (49%, nivolumab plus chemotherapy), 105 (32%, nivolumab plus ipilimumab), and 110 (36%, chemotherapy) patients. Nivolumab plus chemotherapy and nivolumab plus ipilimumab continued to demonstrate clinically meaningful OS benefit versus chemotherapy with no new safety signals identified with longer follow-up, further supporting use as first-line standard treatment options for patients with advanced ESCC.

Scoring PD-L1 Expression in Urothelial Carcinoma: An International Multi-Institutional Study on Comparison of Manual and Artificial Intelligence Measurement Model (AIM-PD-L1) Pathology Assessments.

Assessing programmed death ligand 1 (PD-L1) expression on tumor cells (TCs) using Food and Drug Administration-approved, validated immunoassays can guide the use of immune checkpoint inhibitor (ICI) therapy in cancer treatment. However, substantial interobserver variability has been reported using these immunoassays. Artificial intelligence (AI) has the potential to accurately measure biomarker expression in tissue samples, but its reliability and comparability to standard manual scoring remain to be evaluated. This multinational study sought to compare the %TC scoring of PD-L1 expression in advanced urothelial carcinoma, assessed by either an AI Measurement Model (AIM-PD-L1) or expert pathologists. The concordance among pathologists and between pathologists and AIM-PD-L1 was determined. The positivity rate of ≥ 1%TC PD-L1 was between 20-30% for 8/10 pathologists, and the degree of agreement and scoring distribution for among pathologists and between pathologists and AIM-PD-L1 was similar both scored as a continuous variable or using the pre-defined cutoff. Numerically higher score variation was observed with the 22C3 assay than with the 28-8 assay. A 2-h training module on the 28-8 assay did not significantly impact manual assessment. Cases exhibiting significantly higher variability in the assessment of PD-L1 expression (mean absolute deviation > 10) were found to have patterns of PD-L1 staining that were more challenging to interpret. An improved understanding of sources of manual scoring variability can be applied to PD-L1 expression analysis in the clinical setting. In the future, the application of AI algorithms could serve as a valuable reference guide for pathologists while scoring PD-L1.

PD-L1 Expression in Neoplastic and Immune Cells of Thymic Epithelial Tumors: Correlations with Disease Characteristics and HDAC Expression.

Programmed death-ligand 1 (PD-L1) expression in neoplastic and immune cells of the tumor microenvironment determines the efficacy of antitumor immunity, while it can be regulated at the epigenetic level by various factors, including HDACs. In this study, we aim to evaluate the expression patterns of PD-L1 in thymic epithelial tumors (TETs), while we attempt the first correlation analysis between PD-L1 and histone deacetylases (HDACs) expression. Immunohistochemistry was used to evaluate the expression of PD-L1 in tumor and immune cells of 91 TETs with SP263 and SP142 antibody clones, as well as the expressions of HDCA1, -2, -3, -4, -5, and -6. The PD-L1 tumor proportion score (TPS) was higher, while the immune cell score (IC-score) was lower in the more aggressive TET subtypes and in more advanced Masaoka-Koga stages. A positive correlation between PD-L1 and HDAC-3, -4, and -5 cytoplasmic expression was identified. Higher PD-L1 expression in neoplastic cells and lower PD-L1 expression in immune cells of TETs characterizes more aggressive and advanced neoplasms. Correlations between PD-L1 and HDAC expression unravel the impact of epigenetic regulation on the expression of immune checkpoint molecules in TETs, with possible future applications in combined therapeutic targeting.

A real-world retrospective, observational study of first-line pembrolizumab plus chemotherapy for metastatic non-squamous non-small cell lung cancer with PD-L1 tumor proportion score < 50% (PEMBROREAL).

The phase III Keynote-189 trial established a first-line treatment combining pembrolizumab with pemetrexed and platinum as a standard treatment for patients with stage IV non-small cell lung cancer (NSCLC) without known EGFR and ALK driver mutations and independent of programmed cell death ligand 1 (PD-L1) expression. However, in Italy, eligibility for the National Health Service payment program is limited to patients with PD-L1 <50%. The PEMBROREAL study assesses the real-world effectiveness and safety of pembrolizumab in patients eligible for the National Health Service payment program. PEMBROREAL is a retrospective, observational study on patients with NSCLC who started pembrolizumab combined with pemetrexed and platinum within the reimbursability time window, considered as December 2019 to December 2020. The primary endpoints were to assess progression-free survival (PFS) and overall survival (OS; using the Kaplan-Meier method), response to therapy, and tolerability. Until February 2022, 279 patients (median follow-up: 19.7 months) have been observed. The median PFS was 8.0 months (95% confidence interval: 6.5-9.2). OS was not reached, but we can estimate a 12- to 24-month survival rate for the combined treatment: 66.1% and 52.5%, respectively. PD-L1 expression and Eastern Cooperative Group (ECOG) Performance Status were both associated with PFS and OS. Overall, only 44.4% of patients reported an adverse event, whereas toxicity led to a 5.4% discontinuation rate. The results of the PEMBROREAL study have shown that the combined treatment of pembrolizumab with pemetrexed and platinum is effective for metastatic non-squamous NSCLC, even for patients with PD-L1 levels below 50%, despite the differences in patient demographics and pathological features compared to the Keynote-189 study. The adverse events reported during the study were more typical of chemotherapy treatment rather than immunotherapy, and physicians were able to manage them easily.

Abstract 3730: Impact of proton pump inhibitor on ICI with or without chemotherapy for NSCLC with high PD-L1 TPS

Abstract Background and Aim: Immune checkpoint inhibitors (ICIs) have been widely used for the initial treatment of non-small cell lung cancer (NSCLC). Although both ICI monotherapy and the combination of ICI plus chemotherapy (chemo-ICI) are promising therapeutic options for patients with a programmed cell death ligand-1 tumor proportion score of 50% or higher (high PD-L1), the patient's clinical background and biomarkers differentiating the two options are still not well-defined. In our prior research, we found that a history of proton pump inhibitor (PPI) use independently have negative impact with significantly shorter overall survival (OS) and progression-free survival (PFS) in NSCLC patients harboring high PD-L1 with pembrolizumab monotherapy, but not with chemo-ICI. However, this OS data remain immature. Therefore, in our current study, we extended the follow-up period and conduct additional analysis including OS data to confirm this trend. Method: Advanced NSCLC patients with high PD-L1 who had received pembrolizumab or chemo-ICI as the first-line treatment between March 2017 and December 2020 at 13 hospitals in Japan were analyzed. Survival outcomes were estimated using the Kaplan- Meier method and were compared using the log-rank test. Results: A total of 425 patients with NSCLC were included in the study, with 271 patients (median [range] age, 72 [43-90] years; 215 [79%] men) receiving pembrolizumab monotherapy as their first-line treatment and 154 patients (median [range] age, 69 [36-86] years; 121 [79%] men) receiving chemo-ICI as their first-line treatment. The median follow-up duration was 22.8 months. Among patients with a history of PPI use, both median PFS (19.3 months vs. 6.8 months; HR, 0.53; 95% CI, 0.35-0.78; P = .003) and the median OS(not reached vs. 20.4 months; HR, 0.53; 95% CI, 0.34-0.85; P = .04) were significantly longer in the chemo-ICI group compared to the pembrolizumab monotherapy group. For patients without a history of PPI use, both median PFS (11.4 months vs. 10.8 months; HR, 0.99; 95% CI, 0.76-1.3; P = .36) and the median overall survival (42.2 months vs. 29.9 months, HR, 0.84; 95% CI, 0.62-1.16; P = .33) showed no significant differences between the groups. Discussion and Conclusion: This retrospective study showed that a concomitant treatment with PPI is poor prognostic factor in patients harboring high PD-L1 and treated with ICI monotherapy compared with chemo-ICI in Japanese cohort and this tendency is durable in long-term follow-up. These results indicate that when deciding on an ICI treatment, with or without chemotherapy, it is essential to take into account a concomitant treatment with PPI. Citation Format: Ryo Sawada, Hayato Kawachi, Tadaaki Yamada, Motohiro Tamiya, Yoshiki Negi, Yasuhiro Goto, Akira Nakao, Shinsuke Shiotsu, Takayuki Takeda, Asuka Okada, Taishi Harada, Koji Date, Yusuke Chihara, Isao Hasegawa, Takashi Kijima, Koichi Takayama. Impact of proton pump inhibitor on ICI with or without chemotherapy for NSCLC with high PD-L1 TPS [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3730.

Abstract 5146: Clinical significance of inter-assay discrepancy in PD-L1 expression evaluation for the efficacy of pembrolizumab in advanced NSCLC patients with high PD-L1 expression

Abstract Introduction: The expression of programmed cell death ligand-1 (PD-L1) is a predictive biomarker for the efficacy of pembrolizumab in advanced non-small cell lung cancer (NSCLC). While several assays have been approved for evaluating PD-L1 expression status, the inter-assay discordances are observed. The clinical significance of these discrepancies is still unclear. Methods: We retrospectively reviewed treatment-naïve NSCLC patients with available PD-L1 expression status by both 22C3 and SP142 assays. Among these patients, efficacy analysis was performed in those with PD-L1 tumor proportion score (TPS) ≥ 50% (22C3) who received the first-line pembrolizumab monotherapy. Additionally, we conducted RNA-sequence analysis in the patients with TPS ≥ 50% to investigate the distinct immune profiles with the inter-assay discordance. Results: A total of 611 patients were evaluated for PD-L1 expression status by both assays. Of 198 patients with TPS ≥ 50%, 91 (46%) had TC score ≤ 1 (SP142, i.e., inter-assay discrepancy). In 52 patients who received the first-line pembrolizumab monotherapy, the efficacy in patients with the inter-assay discrepancy was significantly lower than those without the discrepancy (shown in Table). While there was no difference in tumor microenvironments such as the tumor-infiltrating lymphocytes, the transcriptome analysis revealed significantly more CD274 splicing variants with aberrant 3’-terminal sequences in tumors with the inter-assay discrepancy than those without discrepancy, leading to the suppressed PD-1/PD-L1 pathway in those with the discrepancy. Conclusion: The inter-assay discrepancy in the PD-L1 expression status on tumor cells between the 22C3 and SP142 assays, reflecting an imbalance of the CD274 splicing variants, could be a primary-resistance mechanism to the pembrolizumab monotherapy in highly PD-L1-expressing NSCLCs. PD-L1(22C3) Discrepancy Pts. ORR(%) p value Median PFS(months) 95%CI p value TPS ≥ 50% yes 17 18 &amp;lt; 0.001 3.2 0.8–5.5 &amp;lt; 0.001 no 35 83 8.3 5.7–24.2 Citation Format: Jun Miyakoshi, Jumpei Kashima, Masayuki Shirasawa, Masahiro Torasawa, Yuji Matsumoto, Ken Masuda, Yuki Shinno, Yusuke Okuma, Tatsuya Yoshida, Yasushi Goto, Hidehito Horinouchi, Kouya Shiraishi, Takashi Kohno, Noboru Yamamoto, Yasushi Yatabe, Yuichiro Ohe. Clinical significance of inter-assay discrepancy in PD-L1 expression evaluation for the efficacy of pembrolizumab in advanced NSCLC patients with high PD-L1 expression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5146.

Gut microbiome-derived butyrate inhibits the immunosuppressive factors PD-L1 and IL-10 in tumor-associated macrophages in gastric cancer

ABSTRACT Early detection and surgical treatment are essential to achieve a good outcome in gastric cancer (GC). Stage IV and recurrent GC have a poor prognosis. Therefore, new treatments for GC are needed. We investigated the intestinal microbiome of GC patients and attempted to reverse the immunosuppression of the immune and cancer cells of GC patients through the modulation of microbiome metabolites. We evaluated the levels of programmed death-ligand 1 (PD-L1) and interleukin (IL)-10 in the peripheral blood immunocytes of GC patients. Cancer tissues were obtained from patients who underwent surgical resection of GC, and stained sections of cancer tissues were visualized via confocal microscopy. The intestinal microbiome was analyzed using stool samples of healthy individuals and GC patients. Patient-derived avatar model was developed by injecting peripheral blood mononuclear cells (PBMCs) from advanced GC (AGC) patients into NSG mice, followed by injection of AGS cells. PD-L1 and IL-10 had higher expression levels in immune cells of GC patients than in those of healthy controls. The levels of immunosuppressive factors were increased in the immune and tumor cells of tumor tissues of GC patients. The abundances of Faecalibacterium and Bifidobacterium in the intestinal flora were lower in GC patients than in healthy individuals. Butyrate, a representative microbiome metabolite, suppressed the expression levels of PD-L1 and IL-10 in immune cells. In addition, the PBMCs of AGC patients showed increased levels of immunosuppressive factors in the avatar mouse model. Butyrate inhibited tumor growth in mice. Restoration of the intestinal microbiome and its metabolic functions inhibit tumor growth and reverse the immunosuppression due to increased PD-L1 and IL-10 levels in PBMCs and tumor cells of GC patients.

Meta-Analysis of Circulating Tumor Cell PD-L1 Expression and the Association with Clinical Outcomes in Non-Small Cell Lung Cancer.

Programmed death ligand-1 (PD-L1) expression on circulating tumor cells (CTCs) has been suggested to provide prognostic information in non-small cell lung cancer (NSCLC), but consensus relative to treatment outcomes is lacking. We conducted the first comprehensive meta-analysis exploring its potential as a prognostic and predictive marker, and assessed the concordance between PD-L1 + CTCs and paired tumor tissue in NSCLC patients. A comprehensive search was applied to PubMed and EMBASE to identify 26 studies that evaluated PD-L1 + CTCs and their association with survival outcomes in 1236 NSCLC patients. The meta-analysis estimated a mean PD-L1 + CTCs detection rate of 61% (95% CI, 49-72). Subgroup analysis based on treatment showed that PD-L1 + CTCs was not significantly associated with better overall survival (OS) in NSCLC patients treated with immune checkpoint inhibitors (ICIs) (Hazard Ratio (HR) = 0.96, 95% CI, 0.35-2.65, P = 0.944), but was predictive of worse OS in those treated with other therapies (HR = 2.11, 95% CI, 1.32-3.36, P = 0.002). Similarly, PD-L1 + CTCs was not significantly associated with superior progressing free survival (PFS) in NSCLCs treated with ICIs (HR = 0.67, 95% CI, 0.41-1.09, P = 0.121), but was significantly associated with shorter PFS in patients treated with other therapies (HR = 1.91, 95% CI, 1.24-2.94, P = 0.001). The overall estimate for the concordance between PD-L1 expression on CTCs and tumor cells was 63% (95% CI, 44-80). The average detection rate of PD-L1 + CTCs was comparable to the rate of PD-L1 expression in NSCLC tumors. There was a trend towards better PFS in ICI-treated NSCLC patients with PD-L1 + CTCs. Larger longitudinal studies on the association of PD-L1 + CTCs with clinical outcomes in NSCLC patients treated with ICIs are warranted.

Programmed Cell Death-Ligand 1 (PD-L1) Immunohistochemical Expression in Equine Melanocytic Tumors.

Currently available treatments for equine melanocytic tumors have limitations, mainly due to mass localization and dimension, or the presence of metastases. Therefore, a search for new therapies is necessary. Programmed cell death-ligand 1 (PD-L1) is expressed by several tumors, blocking T cell-mediated elimination of the tumor cells by binding to programmed cell death protein 1 (PD-1). A novel therapeutic approach using PD-1/PD-L1 blockade in human melanoma resulted in tumor regression and prolonged tumor-free survival. This study aimed to evaluate the immunohistochemical expression of PD-L1 in equine melanocytic tumors. A total of 77 melanocytic tumors were classified as benign or malignant and evaluated by extension of labeling. A total of 59.7% of the tumors showed >50% of immunolabeled cells. Regarding malignant tumors, 24/38 tumors presented >50% of labeled cells, 13 tumors presented between 25-50% and one tumor presented <10%. Regarding benign tumors, 22/39 tumors presented >50% of labeled cells, nine tumors presented 25-50%, three tumors presented 10-25%, two tumors presented <10% and three tumors did not present expression. Our results suggest that PD-L1 blockade may be a potential target for immunotherapy in equine melanocytic tumors and that future clinical research trials into the clinical efficacy of the anti-PD-L1 antibody are necessary.

Health-related quality of life with pembrolizumab plus chemotherapy vs placebo plus chemotherapy for advanced triple-negative breast cancer: KEYNOTE-355.

In KEYNOTE-355 (NCT02819518), the addition of pembrolizumab to chemotherapy led to statistically significant improvements in progression-free survival and overall survival in patients with advanced triple-negative breast cancer with tumor programmed cell death ligand 1 (PD-L1) combined positive score of at least 10. We report patient-reported outcomes from KEYNOTE-355. Patients were randomly assigned 2:1 to pembrolizumab 200 mg or placebo every 3 weeks for up to 35 cycles plus investigator's choice chemotherapy (nab-paclitaxel, paclitaxel, or gemcitabine plus carboplatin). The European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (QLQ-C30), Breast Cancer-Specific Quality of Life Questionnaire, and EuroQol 5-Dimension questionnaire visual analog scale were prespecified. Patient-reported outcomes were analyzed for patients who received at least 1 dose of study treatment and completed at least 1 patient-reported outcome assessment. Changes in patient-reported outcome scores from baseline were assessed at week 15 (latest time point at which completion and compliance rates were at least 60% and at least 80%, respectively). Time to deterioration in patient-reported outcomes was defined as time to first onset of at least a 10-point worsening in score from baseline. Patient-reported outcome analyses included 317 patients with tumor PD-L1 combined positive score of at least 10 (pembrolizumab plus chemotherapy: n = 217; placebo plus chemotherapy: n = 100). There were no between-group differences in change from baseline to week 15 in QLQ-C30 global health status/quality of life (QOL; least-squares mean difference = -1.81, 95% confidence interval [CI] = -6.92 to 3.30), emotional functioning (least-squares mean difference = -1.43, 95% CI = -7.03 to 4.16), physical functioning (least-squares mean difference = -1.05, 95% CI = -6.59 to 4.50), or EuroQol 5-Dimension questionnaire visual analog scale (least-squares mean difference = 0.18, 95% CI = -5.04 to 5.39) and no between-group difference in time to deterioration in QLQ-C30 global health status/QOL, emotional functioning, or physical functioning. Together with the efficacy and safety findings, patient-reported outcome results from KEYNOTE-355 support pembrolizumab plus chemotherapy as a standard of care for patients with advanced triple-negative breast cancer with tumor PD-L1 expression (combined positive score ≥10).

Progresses in biomarkers for cancer immunotherapy.

Currently, checkpoint inhibitor-based immunotherapy has emerged as prevailing treatment modality for diverse cancers. However, immunotherapy as a first-line therapy has not consistently yielded durable responses. Moreover, the risk of immune-related adverse events increases with combination regimens. Thus, the development of predictive biomarkers is needed to optimize individuals benefit, minimize risk of toxicities, and guide combination approaches. The greatest focus has been on tumor programmed cell death-ligand 1 (PD-L1), microsatellite instability (MSI), and tumor mutational burden (TMB). However, there remains a subject of debate due to thresholds variability and significant heterogeneity. Major unmet challenges in immunotherapy are the discovery and validation of predictive biomarkers. Here, we show the status of tumor PD-L1, MSI, TMB, and emerging data on novel biomarker strategies with oncogenic signaling and epigenetic regulation. Considering the exploration of peripheral and intestinal immunity has served as noninvasive alternative in predicting immunotherapy, this review also summarizes current data in systemic immunity, encompassing solute PD-L1 and TMB, circulating tumor DNA and infiltrating lymphocytes, routine emerging inflammatory markers and cytokines, as well as gut microbiota. This review provides up-to-date information on the evolving field of currently available biomarkers in predicting immunotherapy. Future exploration of novel biomarkers is warranted.

Clinicopathological and prognostic value of TIL and PD L1 in triple negative breast carcinomas

Triple negative breast cancer (TNBC), a highly aggressive subtype of breast cancer, accounts for 15 % of all diagnosed breast cancers. This group, which has the worst clinical outcome, high recurrence rate and poor prognosis, does not benefit from specific treatment. Therefore, there is a need to develop more effective biomarker and therapeutic strategies especially for this group. A positive level of immunity has been found to be associated with patient survival in various organ cancers. More specifically, tumor infiltrating lymphocytes (TIL) have been documented to have strong prognostic value. The programmed cell death 1 (PD 1) protein on the surface of T lymphocytes is activated by the Programmed cell death ligand 1 (PD-L1) protein on the cancer cell surface. PD- L1 is thought to form a pathway that results in suppression of antitumor responses when activated. Patients with breast cancer (BC) who underwent resection without neoadjuvant chemotherapy between 2010 and 2020 were included in this study. Of the 302 BCs examined, 21 constitute the group with TNBC. In our study, the mean age of the Triple positive breast cancer (TPBC) and TNBC groups was similar (55.67 ± 12.61 vs. 53.23 ± 8.21, p = 0.384). There was no significant correlation between TPBC and TNBC and tumor size, lymph node, histological grade, and PD-L1 positivity in the center of the tumor (all p-value >.05). It was observed that tumor stage was higher in patients with TNBC than in patients with TPBC (19 % vs. 1.1 %, p = .002). The Ki 67 proliferation index was found to be higher in patients with TNBC than in patients with TPBC (90.5 % vs. 41.8 %, p .001). Although not statistically significant, clinically, CD 3 and CD 8 immune scores with high tumor margin were higher in patients with TNBC than in patients with TPBC (90.4 % vs, 9.6 % and 85.7 % vs. 14.3 %, respectively). Positive expression of PD-L1 at the tumor margin was significantly higher in patients with TNBC than patients with TPBC (20.3 % vs, 52.4 %, p = .002). By Kaplan-Meier analysis, the survival distribution of CD 3 and CD 8 immunoscore, tumor central and margin PD-L1 values were compared. Mean follow-up was 136.18 months (range, 1 – 144 months); and the 10-year Overall Survival (OS) estimate for the population was 90.9 % (95 % CI, 85.5 – 96.7). In this study, this difference was not statistically significant according to the log-rank test. In this study, we aimed to evaluate the relationship between CD 3, CD 8 T lymphocyte immune score and PD-L1 expression at the tumor center and margin in TNBC, the prognostic value and clinicopathological significance of this relationship.

Assay-agnostic spatial profiling detects tumor microenvironment signatures: new diagnostic insights for triple-negative breast cancer.

The role of the tumor microenvironment (TME) in immuno-oncology has driven demand for technologies that deliver in situ, or spatial, molecular information. Compartmentalized heterogeneity that traditional methods miss is becoming key to predicting both acquired drug resistance to targeted therapies as well as patient response to immunotherapy. Here, we describe a novel method for assay-agnostic spatial profiling and demonstrate its ability to detect immune microenvironment signatures in breast cancer patients that are unresolved by the immunohistochemical (IHC) assessment of programmed cell death ligand-1 (PD-L1) on immune cells, which represents the only FDA microenvironment-based companion diagnostic test that has been approved for triple-negative breast cancer (TNBC). Two distinct physiological states were found that are uncorrelated to tumor mutational burden (TMB), microsatellite instability (MSI), PD-L1 expression, and intrinsic cancer subtypes.

PD-L1 Expression in Pituitary Neuroendocrine Tumors/Pituitary Adenomas.

About a third of Pituitary Neuroendocrine Tumors (PitNETs) may show aggressive behavior. Many efforts have been performed for identifying possible predictive factors to early determine the future behavior of PitNETs. Programmed cell death ligand 1 (PD-L1) expression was associated with a more aggressive biology in different solid tumors, but its role in PitNET is not well-established yet. Our study aims to analyze PD-L1 expression in a surgical cohort of PitNETs to determine its association with radiological invasion and pathology findings, as well as with long-term recurrence rates. We performed a retrospective analysis in a series of 86 PitNETs. Clinical presentation and radiological features of the preoperative period were collected, as well as pathological data and follow-up data. The rate of PD-L1 expression was immunohistochemically evaluated and expressed as a tumor proportion score (TPS). We assessed its relationship with cavernous sinus invasion and Trouillas' classification as primary outcomes. Secondary outcomes included the TPS' relationship with histopathological markers of proliferation, hormonal expression, tumor size and long-term recurrence rates. We calculated the optimal cut-point for the primary outcomes while maximizing the product of the sensitivity and specificity and then we evaluated the significance of secondary outcomes with logistic regression analysis. Eighty-six patients were included in the analysis; 50 cases were non-functional PitNETs. The TPS for PD-L1 showed a highly right-skewed distribution in our sample, as 30.2% of patients scored 0. Using Trouillas' classification, we found that "proliferative" cases have a significantly higher probability to express PD-L1 in more than 30% of tumor cells (OR: 5.78; CI 95%: 1.80-18.4). This same cut-point was also associated with p53 expression. A positive association was found between PD-L1 expression and GH expression (p = 0.001; OR: 5.44; CI 95%: 1.98-14.98), while an inverse relationship was found with FSH/LH expression (p = 0.014; OR = 0.27, CI 95%: 0.10-0.76). No association was found with CS invasion, tumor size, bone erosion or dura invasion. We could not find any association between PD-L1 expression and recurrence. PD-L1 expression was associated with proliferative grades of Trouillas' classification and p53 expression. We also confirmed a higher expression of PD-L1 in somatotroph tumors. Larger studies are necessary to investigate the relationship between PD-L1 expression and aggressive behaviors.

Immunohistological analysis of B7-H4, IDO1, and PD-L1 expression and tumor immune microenvironment based on triple-negative breast cancer subtypes.

B7 homolog 4 (B7-H4) and indoleamine 2,3-dioxygenase (IDO1) are factors involved in the inhibition of antitumor activity and are new therapeutic targets for immune checkpoint therapy. Our study aimed to simultaneously investigate the interrelationship among B7-H4, IDO1 and programmed cell death ligand 1 (PD-L1) expression in triple-negative breast cancer (TNBC), including tumor immune microenvironment (TIME) and TNBC subtypes. Immunostaining for PD-L1, B7-H4, and IDO1 was performed on whole-slide sections of 119 cases of TNBC. The TIME was evaluated based on stromal tumor infiltrating lymphocytes (sTILs; %), pattern classification of TILs, tumor-stroma ratio (TSR), and tertiary lymphoid structure (TLS). TNBC subtypes were also determined by immunohistochemistry analysis of cytokeratin 5/6 and androgen receptor (AR) expression. B7-H4 expression was significantly higher in cases with a combined positive score cutoff of 5 for PD-L1 (clone 28-8; p = 0.021), inflamed TIL pattern (p = 0.007), and TLS ≥ 4 (p = 0.006). B7-H4 expression was higher in case of CK5/6 ≥ 10 (p = 0.035). The H-scores of AR and B7-H4 were inversely correlated (ρ = -0.509, p < 0.001). B7-H4 and IDO1 expression levels were inversely correlated in cases with AR < 10 (ρ = -0.354, p < 0.001). These results suggest that considering the TIL pattern and TLS and identifying the expression of PD-L1 and the basal-like type are useful for estimating B7-H4 expression. In addition, luminal androgen receptor (LAR)-type is frequently deficient in B7-H4 expression. In non-LAR types, B7-H4 and IDO1 expression are exclusive.

A novel 68Ga-labeled cyclic peptide molecular probe based on the computer-aided design for noninvasive imaging of PD-L1 expression in tumors

Programmed death-ligand 1 (PD-L1) serves as a crucial biomarker for guiding the screening of cancer patients and the stratification of immunotherapy. However, due to the high heterogeneity of tumors, the current gold standard for detecting PD-L1 expression (immunohistochemistry) fails to comprehensively evaluate the overall PD-L1 expression levels in the body. Fortunately, the use of PD-L1 targeted radiotracers enables quantitative, real-time, and noninvasive assessment of PD-L1 expression levels and dynamics in tumors. Notably, analyzing the binding mode between the precursor and the target protein to find linker binding sites that do not affect the activity of the target molecule can greatly enhance the successful development of molecular probes. This study introduced a groundbreaking cyclic peptide molecular probe called 68Ga-DOTA-PG1. It was derived from the BMS-71 cyclic peptide and was specifically designed to evaluate the expression of PD-L1 in tumors. The radiolabeling yield of 68Ga-DOTA-PG1 surpassed 97% while maintaining a radiochemical purity of over 99%. In vitro experiments demonstrated the effective targeting of PD-L1 in tumor cells by 68Ga-DOTA-PG1, with significantly higher cellular uptake observed in A375-hPD-L1 cells (PD-L1 + ) compared to A375 cells (PD-L1-). Biodistribution and PET imaging studies consistently showed specific accumulation of 68Ga-DOTA-PG1 in A375-hPD-L1 tumors, with a maximum uptake of 11.06 ± 1.70% ID/g at 2 h, significantly higher than the tumor uptake in A375 cells (1.70 ± 0.17% ID/g). These results strongly indicated that 68Ga-DOTA-PG1 held great promise as a PET radiotracer for imaging PD-L1-positive tumors.

Nanomedicine integrating the lipidic derivative of 5-fluorouracil, miriplatin and PD-L1 siRNA for enhancing tumor therapy

Immunosuppressive microenvironments present critical problems in clinical chemotherapy. To regulate the tumor immune microenvironment for enhancing antitumor effect, a combination of immune checkpoint inhibitors (ICIs) with chemotherapeutics has been applied clinically. In this study, miriplatin (MiPt), the lipidic derivative of 5-fluorouracil (Fu-OA), as well as the programmed death ligand 1 (PD-L1) target siRNA (siPD-L1) were integrated into Lip-Pt/Fu@siPD-L1 nanoparticles (NPs) for chemo-immunotherapy. In vitro results showed that Lip-Pt/Fu@siPD-L1 NPs could exhibit effective siRNA gene silencing and promote the phagocytosis of tumor cells by macrophages. Furthermore, in vivo results revealed that Lip-Pt/Fu@siPD-L1 NPs showed significantly higher anti-tumor efficiency than that of the physical mixing of MiPt, 5-fluorouracil, and Lip@siPD-L1 NPs (delivery of siPD-L1 by liposomes). The best anti-tumor efficiency of Lip-Pt/Fu@siPD-L1 NPs resulted from the synergistic immunotherapeutic effects of MiPt and siPD-L1 based on the inhibition of CD47 expression and the downregulation of PD-L1 in tumor cells, which elicited a robust anti-tumor immune response through the activation of macrophage phagocytosis and immune checkpoint inhibition. The Lip-Pt/Fu@siPD-L1 NPs provide a potential strategy for tumor chemo-immunotherapy.

Dual Synergistic Tumor-Specific Polymeric Nanoparticles for Efficient Chemo-Immunotherapy.

Chemo-immunotherapy has made significant progress in cancer treatment. However, the cancer cell self-defense mechanisms, including cell cycle checkpoint and programmed cell death-ligand 1 (PD-L1) upregulation, have greatly hindered the therapeutic efficacy. Herein, norcantharidin (NCTD)-platinum (Pt) codelivery nanoparticles (NC-NP) with tumor-sensitive release profiles are designed to overcome the self-defense mechanisms via synergistic chemo-immunotherapy. NC-NP remains stable under normal physiological conditions but quickly releases 1,2-diaminocyclohexane-platinum(II) (DACHPt, a parent drug of oxaliplatin) and NCTD in response to the tumor acidity. NCTD inhibits protein phosphatase 2A (PP2A) activity to relieve cell cycle arrest and downregulates the tumor PD-L1 expression to disrupt the programmed cell death-1 (PD-1)/PD-L1 interaction, synergistically enhancing Pt-based chemotherapy and immunogenic cell death-induced immunotherapy. As a result, NC-NP exhibits potent synergistic cytotoxicity and promotes T cell recruitment to generate robust antitumor immune responses. The dual synergism exhibits potent antitumor activity against orthotopic 4T1 tumors, providing a promising chemo-immunotherapy paradigm for cancer treatment.

Association of PD-L1 tumor proportion score ≥20% with early resistance to osimertinib in patients with EGFR-mutated NSCLC.

The relationship between epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) resistance, including osimertinib, and programmed cell death-ligand 1 (PD-L1) expression status in EGFR-mutated non-small cell lung carcinoma (NSCLC) remains unclear. We retrospectively analyzed 64 patients with unresectable advanced or metastatic NSCLC carrying EGFR exon 19 deletions (ex19del) or EGFR exon 21 L858R substitutions (L858R) who received osimertinib as the first-line treatment. We compared progression-free survival (PFS) between eligible patients with PD-L1 tumor proportion scores (TPS) ≥20% and PD-L1 TPS <20% using the Kaplan-Meier survival plots with a log-rank test. Multivariate analysis was performed to examine the poor prognostic factors of PFS. The PD-L1 TPS ≥20% group included 22 cases (median [range] age: 70.5 [33-86] years; 10 women [45.5%]; 11 current or ex-smokers [50%]); ECOG performance status (PS) of 0-1/2/3/4 was noted in 16/4/1/1 patients, respectively. The PD-L1 TPS <20% group included 42 patients (median [range] age 73 [43-88] years; 29 women [69%]; 12 current or ex-smokers [28.6%]); ECOG PS of 0-1/2/3/4 was noted in 33/6/3/0 cases, respectively. The median PFS was 9.1 and 28.1 months in the PD-L1 TPS ≥20% and PD-L1 TPS <20% groups, respectively (log-rank p = 0.013). Multivariate analysis revealed that PD-L1 TPS ≥20% was associated with PFS (hazard ratio: 2.35, 95% confidence interval: 1.09-5.08, p = 0.030). PD-L1 TPS ≥20% in patients with EGFR-mutated NSCLC may be associated with early resistance to osimertinib.

Pembrolizumab plus chemotherapy for advanced non-small-cell lung cancer without tumor PD-L1 expression in Asia.

Aim: We pooled patient-level data from three randomized controlled studies to evaluate the combination of pembrolizumab plus chemotherapy in patients with untreated advanced/metastatic NSCLC and programmed cell death ligand 1 (PD-L1)tumor proportion score <1% in East Asia. Methods: The analysis included 107 patients from China, Japan, Korea, Thailand and Taiwan (pembrolizumab plus chemotherapy, n=56; chemotherapy alone, n=51). Results: For pembrolizumab plus chemotherapy versus chemotherapy alone, median overall survival was 21.3 versus 12.6months (HR, 0.55 [95% CI: 0.35-0.87]) and median progression-free survival (PFS) was 8.4 versus 6.0months (HR, 0.64 [95% CI: 0.43-0.96]). Conclusion: The analysis supports the use of pembrolizumab in combination with platinum-based chemotherapy for East Asian patients with PD-L1-negative, advanced NSCLC.