Adverse prognostic value of PD-L1 expression in primary resected pulmonary squamous cell carcinomas and paired mediastinal lymph node metastases

PD-L1 Scoring Models for Non-Small Cell Lung Cancer in China: Current Status, AI-Assisted Solutions and Future Perspectives

Immunotherapy has revolutionized the diagnosis and treatment model for patients with advanced non-small cell lung cancer (NSCLC). Numerous clinical trials and real-world reports have confirmed that PD-L1 status is a key factor for the successful use of immunotherapy in NSCLC, by predicting clinical outcomes and identifying patients most likely to benefit from this treatment. Therefore, accurate and standardized evaluation of PD-L1 expression is crucial. Currently, PD-L1 testing in China faces several challenges, including a heavy pathologist workload, a shortage of highly trained pathologists plus the inadequate capacity of diagnostic laboratories, confusion around different scoring methods, cut-off values, and indications, and limited concordance between PD-L1 assays. In this review, we summarize the current status and limitations of PD-L1 testing for patients with NSCLC in China and discuss recent progress in artificial intelligence-assisted PD-L1 scoring. Our review aims to support improvements in clinical PD-L1 testing practice and optimization of the prognosis and outcomes of immunotherapy in this patient population.

Predicting Durable Clinical Benefits of Postoperative Adjuvant Chemotherapy in Non-small Cell Lung Cancer: A Nomogram Based on CT Imaging and Immune Type

PURPOSE

To develop a model based on conventional CT signs and the tumor microenvironment immune types (TIMT) to predict the durable clinical benefits (DCB) of postoperative adjuvant chemotherapy in non-small cell lung cancer (NSCLC).

METHODS AND MATERIALS

A total of 205 patients with NSCLC underwent preoperative CT and were divided into two groups: DCB (progression-free survival (PFS) ≥ 18 months) and non-DCB (NDCB, PFS <18 months). The density percentiles of PD-L1 and CD8 + tumor-infiltrating lymphocytes (TIL) were quantified to estimate the TIMT. Clinical characteristics and conventional CT signs were collected. Multivariate logistic regression was employed to select the most discriminating parameters, construct a predictive model, and visualize the model as a nomogram. Receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA) were used to evaluate prediction performance and clinical utility.

RESULTS

Precisely 118 patients with DCB and 87 with NDCB in NSCLC received postoperative adjuvant chemotherapy. TIMT was statistically different between the DCB and NDCB groups (P < 0.05). Clinical characteristics (neuron-specific enolase, squamous cell carcinoma antigen, Ki-76, and cM stage) and conventional CT signs (spiculation, bubble-like lucency, pleural retraction, maximum diameter, and CT value of the venous phase) varied between the four TIMT groups (P < 0.05). Furthermore, clinical characteristics (lymphocyte count [LYMPH] and cM stage) and conventional CT signs (bubble-like lucency and Pleural effusion) differed between the DCB and NDCB groups (P < 0.05). Multivariate analysis revealed that TIMT, cM stage, LYMPH, and pleural effusion were independently associated with DCB and were used to construct a nomogram. The area under the curve (AUC) of the combined model was 0.70 (95%CI: 0.64-0.76), with sensitivity and specificity of 0.73 and 0.60, respectively.

CONCLUSION

Conventional CT signs and the TIMT offer a promising approach to predicting clinical outcomes for patients treated with postoperative adjuvant chemotherapy in NSCLC.

Programmed Death Ligand-1 and Tumor Mutation Burden Testing of Patients With Lung Cancer for Selection of Immune Checkpoint Inhibitor Therapies: Guideline From the College of American Pathologists, Association for Molecular Pathology, International Association for the Study of Lung Cancer, Pulmonary Pathology Society, and LUNGevity Foundation

CONTEXT.—

Rapid advancements in the understanding and manipulation of tumor-immune interactions have led to the approval of immune therapies for patients with non-small cell lung cancer. Certain immune checkpoint inhibitor therapies require the use of companion diagnostics, but methodologic variability has led to uncertainty around test selection and implementation in practice.

OBJECTIVE.—

To develop evidence-based guideline recommendations for the testing of immunotherapy/immunomodulatory biomarkers, including programmed death ligand-1 (PD-L1) and tumor mutation burden (TMB), in patients with lung cancer.

DESIGN.—

The College of American Pathologists convened a panel of experts in non-small cell lung cancer and biomarker testing to develop evidence-based recommendations in accordance with the standards for trustworthy clinical practice guidelines established by the National Academy of Medicine. A systematic literature review was conducted to address 8 key questions. Using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach, recommendations were created from the available evidence, certainty of that evidence, and key judgments as defined in the GRADE Evidence to Decision framework.

RESULTS.—

Six recommendation statements were developed.

CONCLUSIONS.—

This guideline summarizes the current understanding and hurdles associated with the use of PD-L1 expression and TMB testing for immune checkpoint inhibitor therapy selection in patients with advanced non-small cell lung cancer and presents evidence-based recommendations for PD-L1 and TMB testing in the clinical setting.

Genomic discordances and heterogeneous mutational burden, PD-L1 expression and immune infiltrates of non-small cell lung cancer metastasis

AIMS

To investigate the genomic discordances and heterogeneous mutational burden, PD-L1 expression and immune cell (IC) infiltrates of non-small cell lung cancer (NSCLC) metastasis.

METHODS

Surgical samples from 41 cases of NSCLC with metastatic tumours (MTs) and paired primary tumours (PTs) were collected. PD-L1 expression and ICs were quantified using image-based immunohistochemistry profiling. Whole exome sequencing was employed to explore discrepancies in genomic characteristics, tumour mutational burden (TMB) and tumour neoantigen burden (TNB) in 28 cases.

RESULTS

Non-synonymous mutations in MTs were slightly more than in PTs, with only 42.34% of mutations shared between paired PTs and MTs. The heterogeneity of TMB showed no significant difference (p=0.785) between MTs and PTs, while TNB significantly increased in MTs (p=0.013). MTs generally exhibited a higher density of PD-L1+ cells and a higher tumour proportion score with a lower density of IC infiltrates. Subgroup analysis considering clinicopathological factors revealed that the heterogeneity of immune biomarkers was closely associated with the histology of lung adenocarcinoma, metastatic sites of extrapulmonary, time intervals and treatment history. Prognosis analysis indicated that a high density of CD8+ T cells was a low-risk factor, whereas a high density of PD-L1+ cells in MTs was a high-risk factor for cancer-related death in metastatic NSCLC.

CONCLUSIONS

The mutational burden, PD-L1 expression and IC infiltrates undergo changes during NSCLC metastasis, which may impact the immunotherapeutic benefits in patients with NSCLC with metastatic progression and should be monitored according to clinical scenarios.

Spatial metabolomics identifies distinct tumor-specific and stroma-specific subtypes in patients with lung squamous cell carcinoma

Molecular subtyping of lung squamous cell carcinoma (LUSC) has been performed at the genomic, transcriptomic, and proteomic level. However, LUSC stratification based on tissue metabolomics is still lacking. Combining high-mass-resolution imaging mass spectrometry with consensus clustering, four tumor- and four stroma-specific subtypes with distinct metabolite patterns were identified in 330 LUSC patients. The first tumor subtype T1 negatively correlated with DNA damage and immunological features including CD3, CD8, and PD-L1. The same features positively correlated with the tumor subtype T2. Tumor subtype T4 was associated with high PD-L1 expression. Compared with the status of subtypes T1 and T4, patients with subtype T3 had improved prognosis, and T3 was an independent prognostic factor with regard to UICC stage. Similarly, stroma subtypes were linked to distinct immunological features and metabolic pathways. Stroma subtype S4 had a better prognosis than S2. Subsequently, analyses based on an independent LUSC cohort treated by neoadjuvant therapy revealed that the S2 stroma subtype was associated with chemotherapy resistance. Clinically relevant patient subtypes as determined by tissue-based spatial metabolomics are a valuable addition to existing molecular classification systems. Metabolic differences among the subtypes and their associations with immunological features may contribute to the improvement of personalized therapy.

Impact of the immune molecular profile of the tumor microenvironment on the prognosis of NSCLC

The present study aimed to clarify the association between macrophages, tumor neo-vessels and programmed cell death-ligand 1 (PD-L1) in the tumor microenvironment and the clinicopathological features of patients with non-small cell lung cancer (NSCLC), and to explore the prognostic factors of stromal features in NSCLC. To determine this, tissue microarrays containing samples of 92 patients with NSCLC were studied using immunohistochemistry and immunofluorescence. The quantitative data demonstrated that in tumor islets, the number of CD68⁺ and CD206⁺ tumor-associated macrophages (TAMs) was 8-348 (median, 131) and 2-220 (median, 52), respectively (P<0.001). In tumor stroma, the number of CD68⁺ and CD206⁺ TAMs was 23-412 (median, 169) and 7-358 (median, 81), respectively (P<0.001). The number of CD68⁺ TAMs in each location of the tumor islets and tumor stroma was significantly higher than that of CD206⁺ TAMs, and they were significantly correlated (P<0.0001). The quantitative density of CD105 and PD-L1 in tumor tissues was 19-368 (median, 156) and 9-493 (median, 103), respectively. Survival analysis revealed that a high density of CD68⁺ TAMs in tumor stroma and islets and a high density of CD206⁺ TAMs and PD-L1 in tumor stroma were associated with worse prognosis (both P<0.05). Collectively, the survival analysis demonstrated that the high-density group was related to a worse prognosis regardless of combined neo-vessels and PD-L1 expression with the CD68⁺ TAMs in tumor islets and stroma, or CD206⁺ TAMs in tumor islets and stroma. To the best of our knowledge, the present study was the first to provide a multi-component combined prognostic survival analysis of different types of macrophages in different regions with tumor neo-vessels and PD-L1, which demonstrated the importance of macrophages in tumor stroma.

Image analysis reveals molecularly distinct patterns of TILs in NSCLC associated with treatment outcome

Despite known histological, biological, and clinical differences between lung adenocarcinoma (LUAD) and squamous cell carcinoma (LUSC), relatively little is known about the spatial differences in their corresponding immune contextures. Our study of over 1000 LUAD and LUSC tumors revealed that computationally derived patterns of tumor-infiltrating lymphocytes (TILs) on H&E images were different between LUAD (N = 421) and LUSC (N = 438), with TIL density being prognostic of overall survival in LUAD and spatial arrangement being more prognostically relevant in LUSC. In addition, the LUAD-specific TIL signature was associated with OS in an external validation set of 100 NSCLC treated with more than six different neoadjuvant chemotherapy regimens, and predictive of response to therapy in the clinical trial CA209-057 (n = 303). In LUAD, the prognostic TIL signature was primarily comprised of CD4+ T and CD8+ T cells, whereas in LUSC, the immune patterns were comprised of CD4+ T, CD8+ T, and CD20+ B cells. In both subtypes, prognostic TIL features were associated with transcriptomics-derived immune scores and biological pathways implicated in immune recognition, response, and evasion. Our results suggest the need for histologic subtype-specific TIL-based models for stratifying survival risk and predicting response to therapy. Our findings suggest that predictive models for response to therapy will need to account for the unique morphologic and molecular immune patterns as a function of histologic subtype of NSCLC.

Heterogeneity of programmed death-ligand 1 expression and infiltrating lymphocytes in paired resected primary and metastatic non-small cell lung cancer

Metastatic tumors (MTs) may show different characteristics of the immune microenvironment from primary tumors (PTs) in non-small cell lung cancer (NSCLC). The heterogeneity of immune markers in metastatic NSCLC and its associated factors has not been well demonstrated. In this study, 64 surgically resected specimens of paired PTs and MTs were obtained from 28 patients with NSCLC. Multiplex immunofluorescence (mIF; panel including programmed death-ligand 1 (PD-L1), Cytokeratin, CD8, and CD68) was performed on whole sections. The heterogeneity of the immune contexture of PD-L1 expression, infiltrating lymphocytes, and immune-to-tumor cell distances was quantified via digital image analysis. In a quantitative comparison of MTs and corresponding PTs, MTs showed higher PD-L1 expression levels, lower density of CD8+ cytotoxic T lymphocytes (CTLs), and longer spatial distance between CTLs and tumor cells. Subgroup analysis, which associated clinical factors, revealed that the heterogeneity of immune markers was more obvious in extrapulmonary, metachronous, and treated MTs, while fewer differences were observed in intrapulmonary, synchronous, and untreated MTs. In particular, MTs showed significantly higher PD-L1 expression and lower lymphocyte infiltration in metastatic NSCLC with EGFR mutations. Prognosis analysis showed that an increased density of CD8+ CTLs in MTs was associated with better overall survival (OS). Therefore, significant discrepancies in PD-L1 expression and lymphocyte infiltration in metastatic NSCLC are most likely associated with temporal heterogeneity with a history of anti-treatment and correlated with EGFR mutations. The detection of immune markers in re-obtained metastatic specimens may be required for immunotherapy prediction in these patients with metastatic NSCLC.

A prediction model integrated genomic alterations and immune signatures of tumor immune microenvironment for early recurrence of stage I NSCLC after curative resection

BACKGROUND

Surgery is the standard treatment for patients with stage I non-small cell lung cancer (NSCLC). However, postoperative recurrence leads to a poor prognosis of patients. Currently, there is no effective prognostic biomarker and perioperative treatment for patients with stage I NSCLC.

METHODS

One hundred thirty stage I NSCLC patients who had surgical resection were enrolled, including 69 patients who had recurrence within three years and 61 patients who had no recurrence (follow up more than five years). Whole exome sequencing was performed to evaluate gene mutation, copy number variation, and tumor mutation burden (TMB). Immunohistochemistry was carried out to assess the expression of PD-L1 and the level of CD3+ and CD8+ tumor-infiltrating lymphocytes (TILs). Tumor mutation score (TMS) was constructed with the recurrence-associated genes identified by Lasso regression. Immunoscore (IS) was built based on the location and density of CD3+ and CD8+ TILs. Logistic regression was performed to build a prediction model. Seventy percent of patients were included in the training cohort and 30% patients in the testing cohort. P<0.05 was considered to be statistically significant.

RESULTS

Univariate analysis showed that lung adenocarcinoma (LUAD), MUC4 mutation, and high TMB were related to early recurrence (P=0.008, 0.0008, and <0.0001, respectively). CD3+ and CD8+ TILs within tumor center and invasive margin significantly negatively correlated with recurrence. EGFR mutation and PD-L1 expression had no association with recurrence. Early recurrence group had significantly higher TMS and lower IS (P<0.0001 and P=0.0003, respectively). Multivariate analysis showed that high TMS and low IS were independent predictors for early recurrence (P<0.0001 and P=0.001, respectively). Integrating TMS and IS, we built a recurrence-model with great discrimination and calibration in the training cohort (AUC =0.935; HL test, P=0.2885) and testing cohort (AUC =0.932; HL test, P=0.5515).

CONCLUSIONS

High TMS and low IS were both poor prognostic factors for recurrence in stage I NSCLC. The integrated recurrence-model helps identify patients with high recurrence risk, which provides evidence for future research about perioperative treatment.

PD-L1 Expression in Mismatch Repair-deficient Endometrial Carcinoma and Tumor-associated Immune Cells: Differences Between MLH1 Methylated and Nonmethylated Subgroups

Mismatch repair (MMR)-deficient endometrial carcinomas show increased programmed cell death-ligand 1 (PD-L1) expression compared with MMR-intact endometrial carcinomas, but there are limited data regarding PD-L1 expression between sporadic and inherited carcinomas exhibiting MMR loss. Most of the studies investigating PD-L1 expression in endometrial carcinoma have used tissue microarrays and did not examine all tumor blocks. In this study, we analyzed the expression of PD-L1 in resection specimens of 176 consecutive endometrial carcinomas using all tumor blocks; we compared PD-L1 expression in MMR-deficient endometrial carcinomas, including the MLH1 and PMS2-loss subgroup, and the other MMR-loss subgroups (MSH2 and MSH6, isolated PMS2, and isolated MSH6), with the MMR-intact subgroup. MLH1 methylation was performed in tumors with MLH1 and PMS2 loss. Tumor cell (TC) and tumor-associated immune cell (IC) PD-L1 positivity with a 1% cutoff was observed in 21% (n=37) and 66.5% (n=117) of cases, respectively, and with a 5% cutoff in 5.1% (n=9) and 39.8% (n=70) of cases, respectively. MMR protein deficiency was a statistically significant parameter associated with IC PD-L1 positivity, with 1% and 5% cutoffs on multivariate analysis [odds ratio (OR)=5.236, 95% confidence interval (CI)=2.075-13.211, P=0.001, and OR=3.702, 95% CI=1.759-7.791, P=0.001, respectively]. The multivariate analysis showed that IC PD-L1 positivity, using both 1% and 5% cutoffs, was significantly associated with the MLH1 and PMS2 loss compared with the MMR protein-intact subgroup (MLH1 and PMS2 loss for 1% cutoff: OR=5.104, 95% CI=1.876-13.881, P=0.001, and for 5% cutoff: OR=3.322, 95% CI=1.540-7.166, P=0.002). Squamous differentiation was an independent predictor for TC PD-L1 positivity, with a 5% cutoff (OR=6.102, 95% CI=1.280-10.096, P=0.026). Larger tumor size was an independent predictive factor for IC PD-L1 positivity with a 1% cutoff (OR=6.757, 95% CI=1.569-29.109, P=0.010). Overall, 48 (92.3%) of 52 MLH1 methylated tumors showed IC PD-L1 positivity with 1% cutoff, and 34 (65.4%) of 52 MLH1 methylated tumors showed IC PD-L1 positivity with 5% cutoff. Our results show a higher rate of IC PD-L1 positivity than in previous studies. This is likely due in part to the use of all tumor blocks. MLH1 and PMS2 loss was an independent predictive factor for IC PD-L1 positivity, with both 1% and 5% cutoffs. Using univariate analysis, we observed decreased disease-free survival for IC PD-L1 positivity ≥5%. Our study results should now be tested and proven in larger cohorts, with longer follow-up data.

Patterns of carbon-bound exogenous compounds in lung cancer patients and association with disease pathophysiology

Asymptomatic anthracosis is the accumulation of black carbon particles in adult human lungs. It is a common occurrence, but the pathophysiological significance of anthracosis is debatable. Using in situ high mass resolution matrix-assisted laser desorption/ionization (MALDI) fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometry imaging analysis, we discovered noxious carbon-bound exogenous compounds, such as polycyclic aromatic hydrocarbons (PAHs), tobacco-specific nitrosamines, or aromatic amines, in a series of 330 lung cancer patients in highly variable and unique patterns. The characteristic nature of carbon-bound exogenous compound had a strong association with patient outcome, tumor progression, the tumor immune microenvironment, PD-L1 expression, and DNA damage. Spatial correlation network analyses revealed substantial differences in the metabolome of tumor cells compared to tumor stroma depending on carbon-bound exogenous compounds. Overall, the bioactive pool of exogenous compounds is associated with several changes in lung cancer pathophysiology and correlates with patient outcome. Given the high prevalence of anthracosis in the lungs of adult humans, future work should investigate the role of carbon-bound exogenous compounds in lung carcinogenesis and lung cancer therapy.

[Prognostic Analysis of NSCLC Based on the Tumor-associated Macrophages, Tumor Neo-vessels and PD-L1 Expression in Tumor Microenvironment]

背景与目的

肿瘤微环境是肿瘤细胞赖以生存的复杂环境。其中肿瘤相关巨噬细胞（tumor-associated macrophages, TAMs）、肿瘤新生血管及程序性死亡受体1/程序性死亡受体-配体1（programmed cell death protein 1/programmed cell death ligand 1, PD-1/PD-L1）作为关键部分，在肿瘤发生、发展过程中起重要作用，影响患者预后。本研究旨在阐明TAMs、肿瘤新生血管和PD-L1的表达与非小细胞肺癌（non-small cell lung cancer, NSCLC）临床病理特征的相关性，并探讨它们对NSCLC预后的影响。

方法

收集92例NSCLC患者的临床病理资料及手术标本，采用免疫组化法检测癌组织和癌旁组织中TAMs、肿瘤新生血管和PD-L1的表达，采用配备有Olympus-DP72图像采集系统的Olympus-BX51正置显微镜进行拍照并用Image-pro Plus 6.0软件进行半定量分析。

结果

癌组织与癌旁组织中TAMs、肿瘤新生血管和PD-L1的表达差异无统计学意义（P > 0.05）。根据肿瘤微环境中各组分的定量表达，可将其分为低、中、高表达组。癌组织中TAMs的低、中和高密度组的中位总生存（overall survival, OS）分别是36个月（95%CI: 25.3-46.7）、26个月（95%CI: 12.2-39.8）和16个月（95%CI: 9.4-22.6），差异具有统计学意义（P=0.016）；肿瘤新生血管的低、中和高密度组的中位OS分别为30个月（95%CI: 22.5-37.5）、28个月（95%CI: 18.1-37.9）和25个月（95%CI: 14.6-35.4），差异无统计学意义（P=0.626）；PD-L1的低、中和高表达组的中位OS分别为35个月（95%CI: 29.4-40.6），28个月（95%CI: 13.6-42.4）和17个月（95%CI: 10.5-23.5），差异具有统计学意义（P=0.002）。联合低、中和高表达组的中位OS分别为36个月（95%CI: 30.6-41.4）、26个月（95%CI: 19.2-32.8）和9个月（95%CI: 4.4-13.6），差异具有统计学意义（P=0.001）。Cox回归分析结果显示，病理分型、TAMs和PD-L1均为肺癌患者的独立预后因素。

结论

肿瘤微环境关键成分PD-L1及TAMs的表达与NSCLC患者的预后密切相关。

Prevalence and Heterogeneity of PD-L1 Expression by 22C3 Assay in Routine Population-Based and Reflexive Clinical Testing in Lung Cancer

INTRODUCTION

Programmed death-ligand 1 (PD-L1) is used as a biomarker for anti-programmed cell death protein-1 (PD-1) or anti-PD-L1 immunotherapies in NSCLC. We report here the results of population-based PD-L1 testing using the 22C3 IHC pharmDx Assay (Agilent Technologies) in a large Canadian regional reference pathology laboratory.

METHODS

Testing was conducted reflexively on biopsies and resections for NSCLC during an 8-month period. Tumor proportion score (TPS) cutoffs for low and high expression were 1% and 50%, respectively.

RESULTS

Altogether, 2031 PD-L1 tests were performed on specimens from 1795 patients, with 107 inconclusive results (5.3%). Excluding cases with inconclusive/missing data, proportions for the remaining 1713 patients were 41.6% for TPS less than 1%, 28.6% for TPS 1% to 49%, and 29.8% for TPS greater than or equal to 50%. Higher PD-L1 expression rates were noted in EGFR wild-type versus mutant tumors (p < 0.001), squamous versus adenocarcinoma (p < 0.001), and metastatic versus primary tumors (p < 0.001). PD-L1 among 103 patients with paired biopsy and resection specimens revealed moderate concordance (κ = 0.67). A total of 52% (25 of 48) of biopsies with TPS less than 1% had TPS greater than 1% in resection, whereas 84.6% (22 of 26) of biopsies with TPS greater than or equal to 50% were concordant in resected tumors. Discordance rates between biopsy and resection were 71.4% for biopsies with less than 8 mm² total area, compared with 33.3% for biopsies with greater than or equal to 8 mm² area (p < 0.026). Concordance among 27 patients with paired primary lung and metastatic tumor biopsies revealed only weak concordance (κ = 0.48).

CONCLUSIONS

Intratumoral heterogeneity of PD-L1 expression may result in misclassification of PD-L1 status in a substantial proportion of PD-L1-negative small biopsy samples. Biopsy of metastatic site may increase proportion of patients with high PD-L1 expression.

Chemotherapy-induced CDA expression renders resistant non-small cell lung cancer cells sensitive to 5'-deoxy-5-fluorocytidine (5'-DFCR)

BACKGROUND

Pemetrexed (MTA) plus cisplatin combination therapy is considered the standard of care for patients with advanced non-small-cell lung cancer (NSCLC). However, in advanced NSCLC, the 5-year survival rate is below 10%, mainly due to resistance to therapy. We have previously shown that the fraction of mesenchymal-like, chemotherapy-resistant paraclone cells increased after MTA and cisplatin combination therapy in the NSCLC cell line A549. Cytidine deaminase (CDA) and thymidine phosphorylase (TYMP) are key enzymes of the pyrimidine salvage pathway. 5'-deoxy-5-fluorocytidine (5'-DFCR) is a cytidine analogue (metabolite of capecitabine), which is converted by CDA and subsequently by TYMP into 5-fluorouracil, a chemotherapeutic agent frequently used to treat solid tumors. The aim of this study was to identify and exploit chemotherapy-induced metabolic adaptations to target resistant cancer cells.

METHODS

Cell viability and colony formation assays were used to quantify the efficacy of MTA and cisplatin treatment in combination with schedule-dependent addition of 5'-DFCR on growth and survival of A549 paraclone cells and NSCLC cell lines. CDA and TYMP protein expression were monitored by Western blot. Finally, flow cytometry was used to analyze the EMT phenotype, DNA damage response activation and cell cycle distribution over time after treatment. CDA expression was measured by immunohistochemistry in tumor tissues of patients before and after neoadjuvant chemotherapy.

RESULTS

We performed a small-scale screen of mitochondrial metabolism inhibitors, which revealed that 5'-DFCR selectively targets chemotherapy-resistant A549 paraclone cells characterized by high CDA and TYMP expression. In the cell line A549, CDA and TYMP expression was further increased by chemotherapy in a time-dependent manner, which was also observed in the KRAS-addicted NSCLC cell lines H358 and H411. The addition of 5'-DFCR on the second day after MTA and cisplatin combination therapy was the most efficient treatment to eradicate chemotherapy-resistant NSCLC cells. Moreover, recovery from treatment-induced DNA damage was delayed and accompanied by senescence induction and acquisition of a hybrid-EMT phenotype. In a subset of patient tumors, CDA expression was also increased after treatment with neoadjuvant chemotherapy.

CONCLUSIONS

Chemotherapy increases CDA and TYMP expression thereby rendering resistant lung cancer cells susceptible to subsequent 5'-DFCR treatment.

Assessment of Immunological Features in Muscle-Invasive Bladder Cancer Prognosis Using Ensemble Learning

The clinical staging and prognosis of muscle-invasive bladder cancer (MIBC) routinely includes the assessment of patient tissue samples by a pathologist. Recent studies corroborate the importance of image analysis in identifying and quantifying immunological markers from tissue samples that can provide further insight into patient prognosis. In this paper, we apply multiplex immunofluorescence to MIBC tissue sections to capture whole-slide images and quantify potential prognostic markers related to lymphocytes, macrophages, tumour buds, and PD-L1. We propose a machine-learning-based approach for the prediction of 5 year prognosis with different combinations of image, clinical, and spatial features. An ensemble model comprising several functionally different models successfully stratifies MIBC patients into two risk groups with high statistical significance (p value < 1×10-5). Critical to improving MIBC survival rates, our method correctly classifies 71.4% of the patients who succumb to MIBC, which is significantly more than the 28.6% of the current clinical gold standard, the TNM staging system.

Discordance of immunotherapy response predictive biomarkers between primary lesions and paired metastases in tumours: A systematic review and meta-analysis

BACKGROUND

Several biomarkers predict the efficacy of immunotherapy, which is essential for selecting patients who would potentially benefit. Discordant status of these biomarkers between primary tumours and paired metastases has been increasingly revealed. We aimed to comprehensively summarize the incidence of this phenomenon.

METHODS

Databases were searched to identify studies reporting primary-to-metastatic conversion of biomarkers, including programmed death ligand-1 (PD-L1), programmed cell death protein-1 (PD-1), PD-L2, tumour-infiltrating lymphocyte (TIL), tumour mutational burden (TMB), and microsatellite instability (MSI).

FINDINGS

56 studies with 2739 patients were included. The pooled discordance rate of PD-L1 was 22%. The percentage of PD-L1 changed from positive to negative was 41%, whereas that from negative to positive was 16%. The discordance rate for PD-1 and PD-L2 was 26% and 22%, respectively. TIL level was found with a discordance rate of 39%, and changes from high to low (50%) occurred more than that from low to high (16%). No significant difference in TMB was observed between two sites in most studies. MSI status discordance was found in 6% patients, with a percentage of 9% from MSI-high to microsatellite instable (MSS) and 0% from MSS to MSI-high.

INTERPRETATION

Our study demonstrates that PD-L1, PD-1, PD-L2, and TIL level had high frequency of discordance, while TMB and MSI status were less likely to change between primary tumours and paired metastases. Therefore, evaluating those frequently altered biomarkers of both primary and metastatic tumours is strongly recommended for precise clinical decision of immune checkpoint treatment. FUND: The National Natural Science Foundation of China (81872152).

PD-L1 Is a Tumor Suppressor in Aggressive Endometrial Cancer Cells and Its Expression Is Regulated by miR-216a and lncRNA MEG3

BACKGROUND

Poorly differentiated endometrioid adenocarcinoma and serous adenocarcinoma represent an aggressive subtype of endometrial cancer (EC). Programmed death-ligand-1 (PD-L1) was known to exhibit a tumor cell-intrinsic function in mediating immune-independent tumor progression. However, the functional relevance of tumor cell-intrinsic PD-L1 expression in aggressive EC cells and the mechanisms regulating its expression remain unknown.

METHODS

PD-L1 expression in 65 EC tissues and 18 normal endometrium samples was analyzed using immunohistochemical staining. The effects of PD-L1 on aggressive EC cell growth, migration and invasion were investigated by cell functional assays. Luciferase reporter assays were used to reveal the microRNA-216a (miR-216a)-dependent mechanism modulating the expression of PD-L1.

RESULTS

Positive PD-L1 expression was identified in 84% of benign cases but only in 12% of the EC samples, and the staining levels of PD-L1 in EC tissues were significantly lower than those in the normal tissues. Higher PD-L1 expression predicts favorable survival in EC. Ectopic expression of PD-L1 in aggressive EC cells results in decreased cell proliferation and the loss of mesenchymal phenotypes. Mechanistically, PD-L1 exerts the anti-tumor effects by downregulating MCL-1 expression. We found that PD-L1 levels in aggressive EC cells are regulated by miR-216a, which directly targets PD-L1. We further identified a mechanism whereby the long non-coding RNA MEG3 represses the expression of miR-216a, thereby leading to increased PD-L1 expression and significant inhibition of cell migration and invasion.

CONCLUSION

These results reveal an unappreciated tumor cell-intrinsic role for PD-L1 as a tumor suppressor in aggressive EC cells, and identify MEG3 and miR-216a as upstream regulators of PD-L1.

A prognostic model for overall survival of patients with early-stage non-small cell lung cancer: a multicentre, retrospective study

Background

Intratumoural heterogeneity has been previously shown to be related to clonal evolution and genetic instability and associated with tumour progression. Phenotypically, it is reflected in the diversity of appearance and morphology within cell populations. Computer-extracted features relating to tumour cellular diversity on routine tissue images might correlate with outcome. This study investigated the prognostic ability of computer-extracted features of tumour cellular diversity (CellDiv) from haematoxylin and eosin (H&E)-stained histology images of non-small cell lung carcinomas (NSCLCs).

Methods

In this multicentre, retrospective study, we included 1057 patients with early-stage NSCLC with corresponding diagnostic histology slides and overall survival information from four different centres. CellDiv features quantifying local cellular morphological diversity from H&E-stained histology images were extracted from the tumour epithelium region. A Cox proportional hazards model based on CellDiv was used to construct risk scores for lung adenocarcinoma (LUAD; 270 patients) and lung squamous cell carcinoma (LUSC; 216 patients) separately using data from two of the cohorts, and was validated in the two remaining independent cohorts (comprising 236 patients with LUAD and 335 patients with LUSC). We used multivariable Cox regression analysis to examine the predictive ability of CellDiv features for 5-year overall survival, controlling for the effects of clinical and pathological parameters. We did a gene set enrichment and Gene Ontology analysis on 405 patients to identify associations with differentially expressed biological pathways implicated in lung cancer pathogenesis.

Findings

For prognosis of patients with early-stage LUSC, the CellDiv LUSC model included 11 discriminative CellDiv features, whereas for patients with early-stage LUAD, the model included 23 features. In the independent validation cohorts, patients predicted to be at a higher risk by the univariable CellDiv model had significantly worse 5-year overall survival (hazard ratio 1·48 [95% CI 1·06–2·08]; p=0·022 for The Cancer Genome Atlas [TCGA] LUSC group, 2·24 [1·04–4·80]; p=0·039 for the University of Bern LUSC group, and 1·62 [1·15–2·30]; p=0·0058 for the TCGA LUAD group). The identified CellDiv features were also found to be strongly associated with apoptotic signalling and cell differentiation pathways.

Interpretation

CellDiv features were strongly prognostic of 5-year overall survival in patients with early-stage NSCLC and also associated with apoptotic signalling and cell differentiation pathways. The CellDiv-based risk stratification model could potentially help to determine which patients with early-stage NSCLC might receive added benefit from adjuvant therapy.

Funding

National Institue of Health and US Department of Defense.

Chaperone-Mediated Autophagy Markers LAMP2A and HSC70 Are Independent Adverse Prognostic Markers in Primary Resected Squamous Cell Carcinomas of the Lung

LAMP2A and HSC70 are crucial players in chaperone-mediated autophagy (CMA), a targeted, lysosome-dependent protein degradation pathway. Elevated LAMP2A levels, indicative of increased CMA activity, are observed in several malignancies, and CMA downregulation may be exploited therapeutically. We evaluated the impact of LAMP2A and HSC70 in pulmonary squamous cell carcinomas (pSQCC). Antibodies were validated by knockdown and overexpression experiments using three different cell lines. Expression levels in tissue were analyzed by immunohistochemistry in a cohort of 336 consecutive pSQCC using tissue microarrays. There was no significant correlation between the two markers among each other and no association with pathological parameters (TNM categories, grading). However, both high LAMP2A and HSC70 expression were associated with worse outcome, including overall survival (OS; p = 0.012 and p = 0.001) and disease free survival (DFS; p = 0.049 and p = 0.036). In multivariate analysis, both markers and a combination of them were independent adverse prognostic factors for OS (LAMP2Ahigh: HR = 2.059; p < 0.001; HSC70high: HR = 1.987; p < 0.001; LAMP2Ahigh/HSC70high: HR = 1.529; p < 0.001) and DFS (LAMP2Ahigh: HR = 1.709; p = 0.004; HSC70high: HR = 1.484; p = 0.027; LAMP2Ahigh/HSC70high: HR = 1.342, p < 0.001). The negative prognostic impact of high LAMP2A and HSC70 and their variable expression in pSQCC may justify the use of these proteins as potential biomarkers for future CMA-inhibiting therapies.

EpCAM+CD73+ mark epithelial progenitor cells in postnatal human lung and are associated with pathogenesis of pulmonary disease including lung adenocarcinoma

Lung injury in mice induces mobilization of discrete subsets of epithelial progenitor cells to promote new airway and alveolar structures. However, whether similar cell types exist in human lung remains unresolved. Using flow cytometry, we identified a distinct cluster of cells expressing the epithelial cell adhesion molecule (EpCAM), a cell surface marker expressed on epithelial progenitor cells, enriched in the ecto-5'-nucleotidase CD73 in unaffected postnatal human lungs resected from pediatric patients with congenital lung lesions. Within the EpCAM⁺CD73⁺ population, a small subset coexpresses integrin β4 and HTII-280. This population remained stable with age. Spatially, EpCAM⁺CD73⁺ cells were positioned along the basal membrane of respiratory epithelium and alveolus next to CD73⁺ cells lacking EpCAM. Expanded EpCAM⁺CD73⁺ cells give rise to a pseudostratified epithelium in a two-dimensional air-liquid interface or a clonal three-dimensional organoid assay. Organoids generated under alveolar differentiation conditions were cystic-like and lacked robust alveolar mature cell types. Compared with unaffected postnatal lung, congenital lung lesions were marked by clusters of EpCAM⁺CD73⁺ cells in airway and cystic distal lung structures lined by simple epithelium composed of EpCAM⁺SCGB1A1⁺ cells and hyperplastic EpCAM⁺proSPC⁺ cells. In non-small-cell lung cancer (NSCLC), there was a marked increase in EpCAM⁺CD73⁺ tumor cells enriched in inhibitory immune checkpoint molecules CD47 and programmed death-ligand 1 (PD-L1), which was associated with poor survival in lung adenocarcinoma (LUAD). In conclusion, EpCAM⁺CD73⁺ cells are rare novel epithelial progenitor cells in the human lung. Importantly, reemergence of CD73 in lung adenocarcinoma enriched in negative immune checkpoint molecules may serve as a novel therapeutic target.

Selected highlights of the 2019 Pulmonary Pathology Society Biennial Meeting: PD-L1 test harmonization studies

Immune checkpoint inhibitors (ICI) including programmed death 1 (PD-1) inhibitors, such as nivolumab and pembrolizumab, or programmed death ligand 1 (PD-L1) inhibitors, such as atezolizumab and durvalumab, have recently emerged in advanced stage lung cancer as new standards of care. They are now indicated in first- line and second- or later-line treatment of metastatic or locally-advanced stage III non-small cell lung cancer (NSCLC), as well as for metastatic small cell lung cancer (SCLC), as single agent immunotherapy or in combination with chemotherapy. Four PD-L1 immunohistochemistry (IHC) assays have been established and validated in randomized trials, each for a specific ICI. They use different primary monoclonal antibodies, platforms and detection systems, as well as different scoring systems to assess PD-L1 expression either by tumor cells (TCs) and/or by infiltrating immune cells (ICs). Most studies have shown a close analytical performance of three of these clinically-validated standardized assays, but their use restricted to dedicated platforms, which are not all available in most laboratories, questions their applicability. In addition, the relative high costs of the assays have led to the development of in-house protocols in many pathology laboratories. Their use in clinical practice to assess the predictive value of PD-L1 expression for prescription of ICI raises the issue of their reliability and their validation as compared to standardized assays. This article discusses the main comparative studies available between LDT and assays, with clear evidence that LDT can reach a performance equivalent to the trial-validated assays. The requirements are an adequate validation as compared to an appropriate standard, and the participation to external quality assurance programs and training programs for PD-L1 IHC assessment for pathologists.

Validation of the International Tumor Budding Consensus Conference (ITBCC) 2016 recommendation in squamous cell carcinoma of the lung-a single-center analysis of 354 cases

There are no universally accepted grading systems in pulmonary squamous cell carcinoma (pSQCC). Recently, tumor budding, cell nest size, and spread through airspaces (STAS) have been proposed as grading scheme candidates. Tumor budding is a well-established independent prognostic factor in colorectal cancer. The International Tumor Budding Consensus Conference (ITBCC) provided consensus on scoring in 2016, albeit for colorectal cancers. Here, we aimed to validate the ITBCC method in pSQCC and evaluate additional proposed grading parameters. We analyzed a fully clinico-pathologically annotated Western single-center cohort of 354 consecutive primary resected pSQCC (resected 2000-2013). Patients with SQCC of other organs were excluded to reliably exclude lung metastases. We assessed conventional grading, keratinization, STAS, and tumor budding according to ITBCC recommendations, and correlated them with clinico-pathological parameters and survival. Tumor budding was low (0-4 buds/0.785 mm²) in 41%, intermediate (5-9 buds/0.785 mm²) in 30%, and high (≥10 buds/0.785 mm²) in 29% of cases (mean bud count = 7.45 (H&E), min = 0, max = 84). Cell nests of 1, 2-4, 5-15, >15 cells were present in 68%, 20%, 5%, 7%, respectively. We detected STAS in 33% of cases, desmoplasia in 68%. Tumor budding assessed as continuous and categorized variables was highly concordant between hematoxylin and eosin (H&E) and pancytokeratin (AE1/AE3) stained slides (P < 0.001) and significantly associated with tumor size, UICC/AJCC pT, pN, stage (all P < 0.001) and presence of mediastinal lymph node metastases (H&E: P = 0.028). Tumor budding was a significant prognostic parameter for overall, disease-specific, and progression-free survival (PFS) (all P < 0.001). ITBCC tumor budding categories were independent prognostic factors for overall survival (HR = 1.581; 95% CI 1.186-2.108; P = 0.002), disease-specific survival (HR = 1.710; 95% CI 1.111-2.632; P = 0.015), and PFS (HR = 1.457; 95% CI 1.123-1.890; P = 0.005). STAS or conventional tumor grade had no prognostic value. In conclusion, we confirm tumor budding as an independent prognostic marker in pSQCC and validate the ITBCC 2016 scoring recommendations in pSQCC.

Comparability of PD-L1 immunohistochemistry assays for non-small-cell lung cancer: a systematic review

Programmed cell death ligand 1 (PD‐L1) immunohistochemistry is used to determine which patients with advanced non‐small‐cell lung cancer (NSCLC) respond best to treatment with PD‐L1 inhibitors. For each inhibitor, a unique immunohistochemical assay was developed. This systematic review gives an up‐to‐date insight into the comparability of standardised immunohistochemical assays and laboratory‐developed tests (LDTs), focusing specifically on tumour cell (TC) staining and scoring. A systematic search was performed identifying publications that assessed interassay, interobserver and/or interlaboratory concordance of PD‐L1 assays and LDTs in tissue of NSCLC patients. Of 4294 publications identified through the systematic search, 27 fulfilled the inclusion criteria and were of sufficient methodological quality. Studies assessing interassay concordance found high agreement between assays 22C3, 28‐8 and SP263 and properly validated LDTs, and lower concordance for comparisons involving SP142. A decrease in concordance, however, is seen with use of cut‐offs, which hampers interchangeability of PD‐L1 immunohistochemistry assays and LDTs. Studies assessing interobserver concordance found high agreement for all assays and LDTs, but lower agreement with use of a 1% cut‐off. This may be problematic in clinical practice, as discordance between pathologists at this cut‐off may result in some patients being denied valuable treatment options. Finally, five studies assessed interlaboratory concordance and found moderate to high agreement levels for various assays and LDTs. However, to assess the actual existence of interlaboratory variation in PD‐L1 testing and PD‐L1 positivity in clinical practice, studies using real‐world clinical pathology data are needed.

The prognostic value of tumour-associated macrophages in Non-Hodgkin's lymphoma: A systematic review and meta-analysis

Tumour-associated macrophages (TAMs) play an important role in the tumour environment and were reported to be associated with poor prognosis in several tumours. However, the prognostic significance of TAMs in Non-Hodgkin's Lymphoma (NHL) remains controversial. Consequently, we aimed to evaluate the relationship between subpopulations of TAMs and clinical outcomes in NHL patients. We did a comprehensive search of the PubMed, elsevier ScienceDirect, and Cochrane databases and extracted hazard ratio (HR) and their corresponding 95% confidence intervals (95% CIs) from eligible studies. Pooling total effect value by the stata statistical software and analysing correlation of TAMs with overall survival (OS) and progression-free survival (PFS). Furthermore, subgroup analysis and sensitivity analysis were also conducted. We deemed eleven studies, including 1211 NHL patients. Our study demonstrated that high-density CD68⁺ TAMs are associated with poor OS (HR: 1.17; 95% CI, 0.81-1.54; P = .000) and poor PFS (HR: 1.15; 95% CI, 0.63-1.67; P = .000) compared with low-density CD68⁺ TAMs in the tumour microenvironment. Similarly, high-density CD163⁺ TAMs can also predict poor OS (HR: 1.52; 95% CI, 1.11-1.92; P = .000) and shorter PFS (HR: 1.52; 95% CI, 0.73-2.30; P = .000). In addition, the high CD163⁺ /CD68⁺ TAMs ratio is significantly correlated with poor OS (HR: 3.59; 95% CI, 0.77-6.40; P = .013). However, in our subgroup analysis, high-density CD68⁺ TAMs in the tumour microenvironment is associated with better OS (HR: 0.75; 95% CI, 0.41-1.09; P = .000) in NHL patients treated with rituximab chemotherapy. Our results suggest that TAMs are a robust predictor of outcomes in NHL.

Comparison of the 7th and 8th Edition of the UICC/AJCC TNM Staging System in Primary Resected Squamous Cell Carcinomas of the Lung-A Single Center Analysis of 354 Cases

Background: The AJCC/UICC TNM (tumor, node, metastasis) classification is a standardized system for the description of anatomical extent and stage grouping of solid malignant tumors and is regularly updated. We aimed at testing the new 2017 8th edition of the TNM classification (TNM8) compared to the former 2009 7th edition (TNM7), in pulmonary squamous cell carcinomas (pSQCC). Methods: We analyzed a clinico-pathologically well-annotated Western single-center cohort of 354 consecutive pSQCC, resected 2000-2013, without previous neoadjuvant therapy. Patients with a clinical history of SQCC of other organs were excluded to reliably exclude lung metastases. Patients in whom TNM was unclear due to multiple tumor nodules were excluded. We reevaluated all pathological records and slides and retrospectively validated pleural invasion for all cases. Raw data of our cohort are provided as Supplementary Material. Results: The stage distribution according to TNM7 was as follows: IA (2009): 59 (16.7%), IB: 75 (21.2%), IIA: 71 (20.1%), IIB: 53 (15.0%), IIIA: 79 (22.3%), IIIB: 7 (2.0%), IV: 10 (2.8%). Staging the cases according to TNM8, 7/354 (2.0%) cases were down-staged, 154 (43.5%) were upstaged; most pronounced between stages IIA(TNM7) and IIB(TNM8), and IIB(TNM7) and IIIA(TNM8). Both staging systems showed significant prognostic impact for overall survival, disease free and disease specific survival and time to recurrence, without significant differences regarding goodness-of-fit criteria (Akaike Information Criterion and Schwarz Bayesian Criterion). Conclusion: In conclusion, we show a significant stage migration between tumors staged using TNM7 and TNM8, without benefit regarding prognostication in our cohort of primary resected pSQCC.

The Clinicopathologic and Prognostic Significance of Programmed Cell Death Ligand 1 (PD-L1) Expression in Patients With Prostate Cancer: A Systematic Review and Meta-Analysis

Background: Programmed cell death ligand 1 (PD-L1) expression has been shown to correlate with poor prognosis in diverse human cancers. However, limited data exist on the prognostic and clinicopathologic significance of PD-L1 expression in prostate cancers (PCa), and the curative effect of anti-PD-1/PD-L1 therapy remains controversial. In this systematic review and meta-analysis, we aimed to evaluate the prognostic and clinicopathologic value of PD-L1 in PCa. Methods: We performed a systematic literature search in the PubMed, Cochrane Library, EMBASE, Web of Science, and SCOPUS databases up to July 21st, 2018. Pooled prevalence of PD-L1 in PCa was calculated using Freeman-Tukey double arcsine transformation by R software version 3.5.0. The data from the studies were examined by a meta-analysis using Review Manager software 5.3 to calculate pooled hazard ratios (HRs) and pooled odds ratios (ORs) with 95% confidence intervals (CIs) to estimate the prognostic and clinicopathologic value of PD-L1 in PCa. Heterogeneity was tested by the Chi-squared test and I ² statistic. Results: Five studies with 2,272 patients were included in this meta-analysis. The pooled prevalence of PD-L1 in PCa was 35% (95% CI 0.32 to 0.37). Both PD-L1 expression (HR = 1.78; 95% CI 1.39 to 2.27; p < 0.00001) and PD-L1 DNA methylation (HR = 2.23; 95% CI 1.51 to 3.29; p < 0.0001) were significantly associated with poor biochemical recurrence-free survival (BCR-FS). PD-L1 tended to have high expression levels in high Gleason score cases (OR = 1.54; 95% CI, 1.17 to 2.03; P = 0.002) and androgen receptor-positive cases (OR = 2.42, 95% CI 1.31 to 4.50; P = 0.005). However, PD-L1 had relatively weak correlation with age, pathologic stage, lymph node metastasis and preoperative PSA level. Conclusions: This meta-analysis confirms the negative prognostic significance of PD-L1 expression and mPD-L1 in PCa patients. Additionally, PD-L1 has a statistically significant correlation with Gleason score and androgen receptor status, while the correlations with age, pathologic stage, lymph node metastasis, and preoperative PSA level were not statistically significant. However, the number of included studies is too small to make the conclusions more convincing, so more retrospective large-cohort studies are expected for the further confirmation of these findings.

Expression Analysis of Autophagy Related Markers LC3B, p62 and HMGB1 Indicate an Autophagy-Independent Negative Prognostic Impact of High p62 Expression in Pulmonary Squamous Cell Carcinomas

Autophagy is involved in maintaining cellular homeostasis under stress conditions. It also plays an important role in various diseases including cancer. Pulmonary squamous cell carcinomas (pSQCC) at present lack targetable molecular alterations, and demand alternative therapeutic options. We assessed the expression levels of autophagy related proteins LC3B, p62, and HMGB1 in 271 primary resected pSQCC by immunohistochemistry, in correlation with clinical and pathological parameters, as a rationale for a potential autophagy directed therapy. LC3B, p62, and HMGB1 staining showed various patterns. LC3B^highp62^low levels, suggested to indicate intact activated autophagy, were associated with prolonged disease specific survival (DSS) and LC3B^highp62^high levels, indicating activated but late stage impaired autophagy, with shorter DSS (p = 0.024). p62^high expression regardless of LC3B, however, showed an even stronger association with shorter DSS (p = 0.015) and was also an independent negative prognostic factor in multivariate analysis (HR = 2.99; 95% CI 1.38–6.52; p = 0.006). HMGB1 expression correlated neither with the expression of LC3B and p62, nor with patients’ outcome. Different states of autophagy characterized by distinct p62 and LC3B expression patterns may be linked to patient’s prognosis in pSQCC. Our results, however, point also to an autophagy independent role of p62 with an even more pronounced prognostic impact compared to autophagy related p62.

High number of PD-1 positive intratumoural lymphocytes predicts survival benefit of cytokine-induced killer cells for hepatocellular carcinoma patients

BACKGROUND & AIMS

Adjuvant cytokine-induced killer (CIK) cells treatment has shown potential in reducing the recurrence rate and prolonging the survival of patients with hepatocellular carcinoma (HCC). We aimed to identify the best predictive biomarker for adjuvant CIK cells treatment in patients with HCC after curative resection.

METHODS

This study retrospectively included 145 pairs of HCC patients by one-to-one propensity score matching. One group received CIK cells transfusion after surgery (surgery-CIK group); the other one group underwent surgery only (surgery-only group). Immunohistochemistry (IHC) was used to measure PD-1, PD-L1, CD4, CD8 and Foxp3 expression in tumour tissues of surgery-CIK group; IHC of PD-1 and PD-L1 was conducted in the surgery-only group.

RESULTS

The surgery-CIK group had a significantly higher disease-free survival (DFS) and overall survival (OS) rates compared to the surgery-only group. Of all the intratumoural biomarkers, in the surgery-CIK group, multivariate analysis showed that a high number of PD-1⁺ tumour infiltrative lymphocytes (TILs) was the only factor that independently predicted favourable OS and DFS. By contrast, in the surgery-only group, no significant correlations between PD-1/PD-L1 expression and survival of patients were identified. Further correlation analysis showed a high number of PD-1⁺ TILs associated with a high number of both CD4⁺ and CD8⁺ TILs in surgery-CIK group.

CONCLUSIONS

A high number of PD-1⁺ TILs can serve as a potent biomarker for adopting CIK cells therapy in HCC patients after curative resection.

The Prognostic Value of Immune Factors in the Tumor Microenvironment of Penile Squamous Cell Carcinoma

The host's immune system plays a pivotal role in many tumor types, including squamous cell carcinomas (SCCs). We aim to identify immunological prognosticators for lymph node metastases (LNM) and disease-specific survival (DSS) in penile SCC. For this retrospective observational cohort study, penile SCC patients (n = 213) treated in the Netherlands Cancer Institute, were selected if sufficient formalin-fixed, paraffin-embedded tumor material was available. Analysis included previously described high-risk human papilloma virus (hrHPV) status, immunohistochemical scores for classical and non-classical human leukocyte antigen (HLA) class I, programmed death ligand-1 (PD-L1) expression, and novel data on tumor-infiltrating macrophages and cytotoxic an regulatory T-cells. Clinicopathological characteristics and extended follow-up were also included. Regression analyses investigated relationships of the immune parameters with LNM and DSS. In the total cohort, diffuse PD-L1 tumor-cell expression, CD163+ macrophage infiltration, non-classical HLA class I upregulation, and low stromal CD8+ T-cell infiltration were all associated with LNM. In the multivariable model, only tumor PD-L1 expression remained a significant predictor for LNM (odds ratio (OR) 2.8, p = 0.05). hrHPV negativity and diffuse PD-L1 tumor-cell expression were significantly associated with poor DSS and remained so upon correction for clinical parameters [hazard ratio (HR) 9.7, p < 0.01 and HR 2.8, p = 0.03]. The only immune factor with different expression in HPV+ and HPV- tumors was PD-L1, with higher PD-L1 expression in the latter (p = 0.03). In the HPV- cohort (n = 158), LNM were associated with diffuse PD-L1 tumor-cell expression, high intratumoral CD163+ macrophage infiltration, and low number of stromal CD8+ T-cells. The first two parameters were also linked to DSS. In the multivariable regression model, diffuse PD-L1 expression remained significantly unfavorable for DSS (HR 5.0, p < 0.01). These results emphasize the complexity of the tumor microenvironment in penile cancer and point toward several possible immunotherapy targets. Here described immune factors can aid risk-stratification and should be evaluated in clinical immunotherapy studies to ultimately lead to patient tailored treatment.