Surgical Resection of SCLC: Prognostic Factors and the Tumor Microenvironment

Comprehensive genomic and spatial immune infiltration analysis of survival outliers in extensive-stage small cell lung cancer receiving first-line chemoimmunotherapy

BACKGROUND

A minority of patients with extensive-stage small cell lung cancer (ES-SCLC) exhibit prolonged survival following first-line chemoimmunotherapy, which warrants the use of reliable biomarkers. Here, we investigated the disparities in genomics and immune cell spatial distribution between long- and short-term survival of patients with ES-SCLC.

METHODS

We retrospectively recruited 11 long-term (>2 years) and 13 short-term (<9 months) ES-SCLC survivors receiving first-line chemoimmunotherapy. The samples were processed using targeted next-generation sequencing (tNGS), programmed death ligand-1 staining, multiplex immunohistochemical staining for immune cells (mIHC), tumor mutation burden (TMB), and chromosomal instability score measurements. The expression of putative genes in SCLC at the bulk and single-cell RNA-sequencing levels, as well as the role of putative genes in pan-cancer immunotherapy cohorts, were analyzed.

RESULTS

At the genomic level, a greater proportion of the smoking signature and higher TMB (>3.1) were associated with favorable survival. At the single-gene and pathway levels, tNGS revealed that MCL1 and STMN1 amplification and alterations in the apoptosis pathway were more common in short-term survivors, whereas alterations in the DLL3, KMT2B, HGF, EPHA3, ADGRB3, lysine deprivation, and HGF-cMET pathways were observed more frequently in long-term survivors. mIHC analysis of immune cells with different spatial distributions revealed that long-term survivors presented increased numbers of M1-like macrophages in all locations and decreased numbers of CD8+ T cells in the tumor stroma. Bulk transcriptomic analysis demonstrated that high levels of STMN1 and DLL3 represented an immune-suppressive tumor immune microenvironment (TIME), whereas HGF indicated an immune-responsive TIME. The expression levels of our putative genes were comparative in both TP53/RB1 mutant-type and TP53/RB1 wild-type. At the single-cell level, STMN1, MCL1, and DLL3 were highly expressed among all molecular subtypes (SCLC-A, SCLC-N, and SCLC-P), with STMN1 being enriched in cell division and G2M checkpoint pathways.

CONCLUSIONS

For ES-SCLC patients receiving first-line chemoimmunotherapy, alterations in DLL3, KMT2B, HGF, EPHA3, and ADGRB3 and a greater proportion of M1-like macrophages infiltration in all locations were predictors of favorable survival, while MCL1 and STMN1 amplification, as well as a greater proportion of CD8+ T cells infiltrating the tumor stroma, predicted worse survival.

Improved survival of patients with stage III small-cell lung cancer with primary resection: A SEER-based analysis

INTRODUCTION

Small cell lung cancer (SCLC) is mostly diagnosed in stage III-IV patients and associated with poor prognosis. To date, surgery is no gold-standard treatment for any SCLC stage and evidence is lacking whether it is beneficial. Here we investigate the impact of surgery, with special attention to stage III SCLC patients, sub-stages and treatment combinations.

METHODS

The overall survival (OS) and cancer-specific survival (CSS) of 33,198 SCLC patients (SEER database) were analyzed retrospectively, using various statistical analyses, including propensity score matching (PSM), recursive partitioning, and sequential landmark analyses.

RESULTS

Independent of stage, the OS of patients with surgery-including treatments was almost always better than without surgery. This holds true for stage I-II patients, even after PMS analysis (p < 0.017). The same was found for stage IV patients that underwent surgery plus chemotherapy vs. chemotherapy alone (p = 0.013 after PSM). Stage III patients showed a robust improvement in OS and CSS after surgery (OS: 18 vs.13 months) or surgery plus chemotherapy (OS: 20 vs.15 months) as confirmed by well-balanced PSM and sequential landmark analyses of long-term survivors. More detailed analyses using two independent approaches showed prolonged OS in T3-4/N0-1 and T1-2/N2 stage III patients after surgery or surgery plus chemotherapy. Importantly, primary site surgery had a major survival advantage over surgery at regional sites (p < 0.003).

CONCLUSION

Our study demonstrates that selected patients of all stages, including stage III T3-4/N0-1 and T1-2/N2, can benefit greatly from surgery-including treatments. Thus, surgery should be included into hospital treatment recommendations for specifically selected SCLC patients. Condensed abstract Primary resection in patients with stage III SCLC needs re-evaluation. Selected patients with stage III SCLC benefit significantly from surgery. Patients with T3-4/N0-1 and T1-2/N2 stage III SCLC should be considered for surgery.

Prediction of Prognosis and Immunotherapy Response with a Novel Natural Killer Cell Marker Genes Signature in Osteosarcoma

Background: Natural killer (NK) cells are characterized by their antitumor efficacy without previous sensitization, which have attracted attention in tumor immunotherapy. The heterogeneity of osteosarcoma (OS) has hindered therapeutic application of NK cell-based immunotherapy. The authors aimed to construct a novel NK cell-based signature to identify certain OS patients more responsive to immunotherapy. Materials and Methods: A total of eight publicly available datasets derived from patients with OS were enrolled in this study. Single-cell RNA sequencing data obtained from the Gene Expression Omnibus (GEO) database were analyzed to screen NK cell marker genes. Least Absolute Shrinkage and Selection Operator (LASSO) Cox regression analysis was used to construct an NK cell-based prognostic signature in the TARGET-OS dataset. The differences in immune cell infiltration, immune system-related metagenes, and immunotherapy response were evaluated among risk subgroups. Furthermore, this prognostic signature was experimentally validated by reverse transcription-quantitative real-time PCR (RT-qPCR). Results: With differentially expressed NK cell marker genes screened out, a five-gene NK cell-based prognostic signature was constructed. The prognostic predictive accuracy of the signature was validated through internal clinical subgroups and external GEO datasets. Low-risk OS patients contained higher abundances of infiltrated immune cells, especially CD8 T cells and naive CD4 T cells, indicating that T cell exhaustion states were present in the high-risk OS patients. As indicated from correlation analysis, immune system-related metagenes displayed a negative correlation with risk scores, suggesting the existence of immunosuppressive microenvironment in OS. In addition, based on responses to immune checkpoint inhibitor therapy in two immunotherapy datasets, the signature helped predict the response of OS patients to anti-programmed cell death protein 1 (PD-1) or anti-programmed cell death ligand 1 (PD-L1) therapy. RT-qPCR results demonstrated the roughly consistent relationship of these five gene expressions with predicting outcomes. Conclusions: The NK cell-based signature is likely to be available for the survival prediction and the evaluation of immunotherapy response of OS patients, which may shed light on subsequent immunotherapy choices for OS patients. In addition, the authors revealed a potential link between immunosuppressive microenvironment and OS.

The effects of surgical resection in the treatment of limited-stage small cell lung cancer: a multicenter retrospective study

This study aimed to examine the effects of surgical resection on the treatment of limited-stage small cell lung cancer and identify patient characteristics that may indicate a benefit from surgical resection. We retrospectively reviewed medical data from patients diagnosed with small cell lung cancer between January 2013 and December 2020 at three hospitals. A total of 478 patients were included in the study, 153 patients received surgery treatment and 325 patients received non-surgery treatment. Survival differences between the surgical resection group and the nonsurgical resection group were analyzed using the Kaplan-Meier method and the log-rank test. The overall survival in the surgical resection group was significantly improved compared to that in the nonsurgical resection group (HR: 0.58, 95% CI: 0.370-0.876, p = 0.0126). Surgical resection significantly improved overall survival compared to nonsurgical resection in stage I disease (HR: 0.56, 95% CI: 0.34-0.94, p = 0.029) and stage IIA disease (HR: 0.60, 95% CI: 0.40-0.92, p = 0.019). However, no significant differences in overall survival were found between surgical resection and nonsurgical resection in stage IIB disease (HR: 0.86, 95% CI: 0.57-1.29, p = 0.46) and stage III disease (HR: 0.99, 95% CI: 0.71-1.39, p = 0.97). The overall survival of patients who underwent lobectomy was significantly better than that of patients who underwent sublobular resection (HR: 1.85, 95% CI: 1.15-4.16, p = 0.021) and who underwent pneumonectomy (HR: 2.04, 95% CI: 1.29-5.28, p = 0.009). Surgical resection should be recommended for patients diagnosed with stage I-IIA SCLC. When deciding on the surgical type, it is preferable to choose lobectomy over sublobar resection or pneumonectomy.

Spread Through Air Spaces in Stage I Pulmonary Large Cell Neuroendocrine Carcinoma

BACKGROUND

Pulmonary large cell neuroendocrine carcinoma (LCNEC) represents an exceptionally aggressive and infrequent variant within the realm of non-small cell lung cancer, necessitating surgical intervention as the primary therapeutic approach. However, the postoperative management strategy for early-stage patients continues to be a subject of intense debate and uncertainty.

METHODS

A retrospective analysis was conducted on a cohort of patients diagnosed with LCNEC who underwent surgical resection at Shanghai Pulmonary Hospital between July 2018 and June 2022. Comprehensive assessments, encompassing univariate and multivariate analyses, were performed to evaluate the prognostic significance of these indicators in patient clinical profiles, overall survival (OS), and disease-free survival (DFS).

RESULTS

A comprehensive screening effort identified 171 patients with LCNEC, with 70 stage I patients meeting the criteria for inclusion in the final cohort. Of these, 11 patients (15.7%) presented with combined LCNEC, and 59 (84.3%) exhibited pure LCNEC. Univariate and multivariate analyses both unveiled that spread through air spaces (STAS) status emerged as an independent prognostic determinant for both DFS (P = .003) and OS (P = .013), whereas histologic subtype independently predicted OS (P = .011). Subgroup survival analyses further underscored that the advantageous effects of postoperative chemotherapy were significantly pronounced exclusively among STAS-positive patients, showcasing a statistically significant enhancement in DFS (P = .047) and OS (P = .018).

CONCLUSIONS

STAS may serve as an adverse prognostic factor in stage I LCNEC patients, potentially offering guidance for postoperative chemotherapy decisions.

A retrospective study on the impact of radiotherapy on the survival outcomes of small cell lung cancer patients based on the SEER database

Small cell lung cancer (SCLC) patients exhibit significant heterogeneity in tumor burden, physical condition, and responses to initial treatment. This diversity in treatment responses can result in varying treatment outcomes. The primary objective of this study was to explore the patient demographics associated with improved survival outcomes through radiotherapy. Based on the SEER database, we identified 42,824 SCLC patients enrolled between 2004 and 2015. These patients were stratified into radiotherapy (n = 20,360) and non-radiotherapy groups (n = 22,464). We controlled for confounding factors using propensity score matching (PSM) analysis. Subsequently, Kaplan-Meier (KM) analysis was employed to evaluate the impact of radiotherapy on patients' overall survival (OS) and cancer-specific survival (CSS). Cancer-specific mortality was further analyzed using competitive risk models. Cox analysis was also conducted to examine additional variables potentially affecting the survival of SCLC patients. We identified a total of 42,824 eligible patients, and following PSM, 13,329 patients were successfully matched in both the radiotherapy and non-radiotherapy groups. The KM analysis showed that the median OS was 9 months in the radiotherapy group and 6 months in the non-radiotherapy group. The median CSS was 10 months in the radiotherapy group and 7 months in the non-radiotherapy group. The 5-year OS and 10-year OS rates were 6.2% versus 1.6% in the radiotherapy group and 2.6% versus 0.8% in the non-radiotherapy group (P < 0.001). Competitive risk analysis showed that cancer-specific mortality was significantly higher in the non-radiotherapy group than in the radiotherapy group (P < 0.001). Multivariate Cox analysis showed that the radiotherapy group (relative non-radiotherapy group) showed a significant positive effect on survival outcomes (OS: HR 0.658 95% CI [0.642, 0.675] P < 0.001; CSS: HR 0.662 95% CI [0.645, 0.679], P < 0.001). In addition, age, gender, race, primary tumor site, T stage, N stage, M stage, chemotherapy, and surgery were also considered as important predictors of SCLC outcome. The results of the subgroup analysis showed that the radiotherapy group showed a significant survival advantage regardless of age, sex, race, primary tumor site, M stage, chemotherapy, and surgery (P < 0.001). Radiotherapy may improve both OS and CSS in SCLC patients. Patients with SCLC may benefit from radiotherapy regardless of age, sex, race, primary tumor site, M stage, chemotherapy, and surgery.

Molecular subtypes of neuroendocrine carcinomas: A cross-tissue classification framework based on five transcriptional regulators

Neuroendocrine carcinomas (NECs) are extremely lethal malignancies that can arise at almost any anatomic site. Characterization of NECs is hindered by their rarity and significant inter- and intra-tissue heterogeneity. Herein, through an integrative analysis of over 1,000 NECs originating from 31 various tissues, we reveal their tissue-independent convergence and further unveil molecular divergence driven by distinct transcriptional regulators. Pan-tissue NECs are therefore categorized into five intrinsic subtypes defined by ASCL1, NEUROD1, HNF4A, POU2F3, and YAP1. A comprehensive portrait of these subtypes is depicted, highlighting subtype-specific transcriptional programs, genomic alterations, evolution trajectories, therapeutic vulnerabilities, and clinicopathological presentations. Notably, the newly discovered HNF4A-dominated subtype-H exhibits a gastrointestinal-like signature, wild-type RB1, unique neuroendocrine differentiation, poor chemotherapeutic response, and prevalent large-cell morphology. The proposal of uniform classification paradigm illuminates transcriptional basis of NEC heterogeneity and bridges the gap across different lineages and cytomorphological variants, in which context-dependent prevalence of subtypes underlies their phenotypic disparities.

Systemic immune index predicts tumor-infiltrating lymphocyte intensity and immunotherapy response in small cell lung cancer

Background

Despite recent progresses in immune checkpoint blockade (ICB) in small-cell lung cancer (SCLC), a lack of understanding regarding the systemic tumor immune environment (STIE) and local tumor immune microenvironment (TIME) makes it difficult to accurately predict clinical outcomes and identify potential beneficiaries from ICB therapy.

Methods

We enrolled 191 patients with stage I-III SCLC and comprehensively evaluated the prognostic role of STIE by several quantitative measurements, and further integrate it with a local immune score system (LISS) established by eXtreme Gradient Boosting (XGBoost) machine learning algorithm. We also test the value of STIE in beneficiary selection in our independent advanced SCLC cohort receiving programmed cell death 1 ligand 1 (PD-L1) blockade therapy.

Results

Among several systemic immune markers, the STIE as assessed by prognostic nutritional index (PNI) was correlated with disease-free survival (DFS) and overall survival (OS), and remained as an independent prognostic factor for SCLC patients [hazard ratio (HR): 0.473, 95% confidence interval (CI): 0.241-0.929, P=0.030]. Higher PNI score was closely associated with inflamed SCLC molecular subtype and local tumor-infiltrating lymphocytes (TILs). We further constructed a LISS which combined top three important local immune biomarkers (CD8+ T-cell count, PD-L1 expression on CD8+ T-cell and CD4+ T-cell count) and integrated it with the PNI score. The final integrated immune risk system was an independent prognostic factor and achieved better predictive performance than Tumor Node Metastasis (TNM) stages and single immune biomarker. Furthermore, PNI-high extensive-stage SCLC patients achieved better clinical response and longer progression-free survival (PFS) (11.8 vs. 5.9 months, P=0.012) from PD-L1 blockade therapy.

Conclusions

This study provides a method to investigate the prognostic value of overall immune status by combining the PNI with local immune biomarkers in SCLC. The promising clinical application of PNI in efficacy prediction and beneficiary selection for SCLC immunotherapy is also highlighted.

New findings in prognostic factor assessment for adenocarcinoma of transverse colon: a comparison study between competing-risk and COX regression analysis

Purpose

Competing-risk analysis was used to accurately assess prognostic factors for cancer-specific death in patients with adenocarcinoma of transverse colon (ATC), and the results were compared with those from a conventional Cox regression analysis.

Materials and Methods

Patients diagnosed with ATC between 2000 and 2019 were selected from the Surveillance, Epidemiology, and End Results database. The crude mortality rates of patients with ATC were calculated and their differences were tested using the Gray's test, respectively. In performing multivariate analysis, the Cox regression model and the subdistribution hazard function (SD) in competing risk analysis were utilized, respectively.

Results

This study included 21,477 eligible patients. The SD model indicated that age, etc. are actual independent prognostic factors. In contrast to previous recognition, the results of the Cox regression showed false-positives for sex and Carcinoembryonic antigen, and underestimated point-estimates in the stage and American Joint Committee on Cancer stage due to competing events. A detailed comparison of treatment revealed that the larger surgical scopes were prognostic risk factors compared with the smaller scope of local tumor excision, partial colectomy, or segmental resection. Patients treated with external proton beam radiotherapy had an increased risk compared with those with no radiotherapy and internal radiotherapy.

Conclusions

After comparing the results of the two methods and mitigating the significant bias introduced by Cox regression, we found independent factors that really affect the prognosis of ATC. On the other hand, in terms of ATC, a larger surgical scope and external proton beam radiotherapy may not improve the long-term survival of patients. Therefore, when faced with ATC patients, these differences should be noted and treated differently from common colorectal cancer patients. Thus, clinicians are able to give more targeted treatment plans and prognostic assessments.

Tissue and circulating biomarkers of benefit to immunotherapy in extensive-stage small cell lung cancer patients

Extensive stage-Small-Cell Lung Cancer (ES-SCLC) is an aggressive cancer with dismal prognosis. The addition of immune-checkpoint inhibitors (ICIs) to platinum-based chemotherapy have been consistently demonstrated to improve outcomes and survival, becoming the new standard in first - line treatment of ES-SCLC patients. However, despite positive results reported in the pivotal trials, longer benefit appears evident only for a selected group of patients. Several predictive biomarkers have been studied so far but the prospective identification of patients more likely to experience better outcome seems to be challenging in SCLC. Indeed, classical immune predictive biomarkers as PD-L1 and tumor mutational burden (TMB) seem not to correlate with outcomes. Recently, a new molecular classification of SCLC based on differential expression of genes associated with specific clinical behaviors and therapeutic vulnerability have been presented suggesting a new field to be investigated. Despite the achievements, these studies focused mainly on inter-tumoral heterogeneity, limiting the exploration of intra-tumoral heterogeneity and cell to cell interactions. New analysis methods are ongoing in order to explore subtypes plasticity. Analysis on single biopsies cannot catch the whole genomic profile and dynamic change of disease over time and during treatment. Moreover, the availability of tissue for translational research is limited due to the low proportion of patients undergoing surgery. In this context, liquid biopsy is a promising tool to detect reliable predictive biomarkers. Here, we reviewed the current available data on predictive role of tissue and liquid biomarkers in ES-SCLC patients receiving ICIs. We assessed latest results in terms of predictive and prognostic value of gene expression profiling in SCLC. Finally, we explored the role of liquid biopsy as a tool to monitor SCLC patients over time.

Histopathology images-based deep learning prediction of prognosis and therapeutic response in small cell lung cancer

Small cell lung cancer (SCLC) is a highly aggressive subtype of lung cancer characterized by rapid tumor growth and early metastasis. Accurate prediction of prognosis and therapeutic response is crucial for optimizing treatment strategies and improving patient outcomes. In this study, we conducted a deep-learning analysis of Hematoxylin and Eosin (H&E) stained histopathological images using contrastive clustering and identified 50 intricate histomorphological phenotype clusters (HPCs) as pathomic features. We identified two of 50 HPCs with significant prognostic value and then integrated them into a pathomics signature (PathoSig) using the Cox regression model. PathoSig showed significant risk stratification for overall survival and disease-free survival and successfully identified patients who may benefit from postoperative or preoperative chemoradiotherapy. The predictive power of PathoSig was validated in independent multicenter cohorts. Furthermore, PathoSig can provide comprehensive prognostic information beyond the current TNM staging system and molecular subtyping. Overall, our study highlights the significant potential of utilizing histopathology images-based deep learning in improving prognostic predictions and evaluating therapeutic response in SCLC. PathoSig represents an effective tool that aids clinicians in making informed decisions and selecting personalized treatment strategies for SCLC patients.

Clinical and molecular characterization of long-term survivors with extensive-stage small cell lung cancer treated with first-line atezolizumab plus carboplatin and etoposide

OBJECTIVES

In the Phase I/III IMpower133 study, first-line atezolizumab plus carboplatin and etoposide (CP/ET) treatment for extensive-stage small cell lung cancer (ES-SCLC) significantly improved overall survival (OS) and progression-free survival versus placebo plus CP/ET. We explored patient and disease characteristics associated with long-term survival in IMpower133, and associations of differential gene expression and SCLC-A (ASCL1-driven), SCLC-N (NEUROD1-driven), SCLC-P (POU2F3-driven), and SCLC-inflamed (SCLC-I) transcriptional subtypes with long-term survival.

MATERIALS AND METHODS

Patients with previously untreated ES-SCLC were randomized 1:1 to four 21-day cycles of CP/ET with atezolizumab or placebo. Long-term survivors (LTS) were defined as patients who lived ≥ 18 months post randomization. A generalized linear model was used to evaluate the odds of living ≥ 18 months. Differential gene expression was analyzed using RNA-sequencing data in LTS and non-LTS. OS was assessed by T-effector and B-cell gene signature expression. Distribution of SCLC transcriptional subtypes was assessed in LTS and non-LTS.

RESULTS

More LTS were in the atezolizumab arm (34%) than in the placebo arm (20%). The odds ratio for living ≥ 18 months in the atezolizumab arm versus the placebo arm was 2.1 (P < 0.03). Enhanced immune-related signaling was seen in LTS in both arms. Exploratory OS analyses showed atezolizumab treatment benefit versus placebo across T-effector and B-cell gene signature expression subgroups. A higher proportion of LTS than non-LTS in both arms had the SCLC-I subtype; this difference was particularly pronounced in the atezolizumab arm.

CONCLUSION

These exploratory analyses suggest that long-term survival is more likely with atezolizumab than placebo in ES-SCLC, confirming the treatment benefit of the IMpower133 regimen.

CLINICALTRIAL

gov Identifier: NCT02763579.

Survival of small-cell lung cancer patients after surgery: A single-center retrospective cohort study

This study summarized and analyzed the clinical characteristics and prognosis of small-cell lung cancer (SCLC) patients after surgical treatment. The clinical data of 130 patients (99 males and 31 females) with SCLC treated by surgery and confirmed by postoperative pathological examination at Peking Union Medical College Hospital from April 2004 to April 2019 were retrospectively analyzed. Clinical characteristics, surgery, pathological stage, and perioperative treatment were summarized. Kaplan-Meier survival curve and Cox regression analysis were performed. Pathological examination revealed that 36 (27.69%) patients had stage I SCLC, 22 (16.92%) patients had stage II SCLC, 65 (50.00%) patients had stage III SCLC, and 7 (5.39%) patients had stage IV SCLC. The overall median survival time was 50 months (95% confidence interval, 10.8-89.2 months). The median survival time of stage I, II, III and IV SCLC patients was 148, 42, 32, and 10 months, respectively. In patients who underwent surgical treatment, postoperative adjuvant therapy and tumor stage were independent prognostic factors for survival (p < 0.05).Lobectomy and lymph nodes resection combined with adjuvant therapy were cautiously recommended for stage I-IIIa SCLC patients.

Shaping the tumor immune microenvironment of SCLC: Mechanisms, and opportunities for immunotherapy

Small-cell lung cancer (SCLC) is a very aggressive neuroendocrine tumor with a poor prognosis. Whereas immunotherapy has emerged as a promising approach for treating SCLC, its unique tumor immune microenvironment (TIME) might limit patient responses. To fully characterize the TIME and understand the mechanism of its formation with respect to SCLC is crucial. The recent rapid development of multi-omics technologies has rapidly advanced knowledge of TIME features and the regulatory mechanisms associated with SCLC. This review summarizes the TIME features of SCLC as well as shaping the TIME according to the genomics, epigenomics, and metabolomics of tumors. Future opportunities and challenges for immunotherapy are also discussed.

Identification of useful biomolecular markers in kidney renal clear cell carcinoma: an in silico and in vitro analysis-based study

BACKGROUND

Kidney renal clear cell carcinoma (KIRC) is the most prevalent type of renal cell carcinoma (RCC), with a high incidence and mortality rate. There is a lack of sensitive biomarkers. Therefore, the discovery of accurate biomarkers for KIRC patients is critical to improve prognosis.

METHODS

We determined hub genes and their associated pathways involved in the pathogenesis of KIRC from the GSE66272 dataset consisting of KIRC (n = 26) and corresponding control (n = 26) samples and later validated the expression and methylation level of the identified hub genes on The Cancer Genomic Atlas (TCGA) datasets and Human RCC 786-O and normal HK-2 cell lines through RNA sequencing (RNA-seq), Reverse transcription-quantitative polymerase chain reaction (RT-qPCR), and targeted bisulfite sequencing (bisulfite-seq) analyses.

RESULTS

The identified up-regulated four hub genes include TYROBP (Transmembrane Immune Signaling Adaptor TYROBP), PTPRC (Protein tyrosine phosphatase, receptor type, C), LCP2 (Lymphocyte cytosolic protein 2), and ITGB2 (Integrin Subunit Beta 2). Moreover, the higher expression of TYROBP, PTPRC, LCP2, and ITGB2 in KIRC patients insignificantly correlates with a poor prognosis in KIRC patients. In addition, hub genes were involved in the "Fc epsilon RI signaling pathway, asthma, natural cell killer mediated cytotoxicity, T cell receptor signaling pathway, primary immunodeficiency, Fc gamma R-mediated phagocytosis, malaria, leukocyte transendothelial migration, and legionellosis" pathways and associated with the infiltration level of CD8+ T, CD4+ T, and macrophage cells.

CONCLUSION

Our integrated in silico and in vitro analysis identified important hub genes (TYROBP, PTPRC, LCP2, and ITGB2) involved in the pathogenesis of KIRC as possible diagnostic biomarkers.

Survival analysis of surgical versus nonsurgical treatment in stage I to III small cell lung cancer in the last 20 years: A systematic review and meta-analysis

More and more patients with small cell lung cancer (SCLC) have received surgical treatment in the last 20 years. This meta-analysis compared whether surgical treatment can bring greater survival benefits to patients with stage I-III SCLC compared with chemotherapy, radiotherapy and chemoradiotherapy. Pubmed, Embase, Web of Science, Cochrane library database, and ClinicalTrials were searched for relevant articles. The main outcomes were overall survival (OS), reported as hazard ratios (HRs), and 95% confidence intervals (CIs). A total of 19 articles containing 30 185 patients (3940 patients receiving surgical treatment and 26 245 patients receiving nonsurgical treatment) were included in this study. Surgical resection significantly improved OS when compared to nonsurgical treatment in retrospective studies (HR: 0.55, 95% CI: 0.47-0.64, p < 0.01). In the subgroup analysis for retrospective studies, surgical resection was associated with superior OS in stage I (HR: 0.42, 95% CI: 0.24-0.71, p < 0.01), stage II (HR: 0.61, 95% CI: 0.52-0.73, p < 0.01), and stage III diseases (HR: 0.66, 95% CI: 0.51-0.86, p < 0.01). Sublobar resection resulted in worse OS than a lobectomy (HR: 0.78,95% CI: 0.60-1.00, p < 0.01) for patients undergoing surgical resection. Compared with nonsurgical treatment, surgical treatment can indeed bring more significant survival benefits to patients with stage I-III SCLC, and lobectomy can bring longer survival compared with sublobectomy. More prospective studies are needed to confirm these findings.

Integrative Analysis of a Large Real-World Cohort of Small Cell Lung Cancer Identifies Distinct Genetic Subtypes and Insights into Histologic Transformation

Small cell lung cancer (SCLC) is a recalcitrant neuroendocrine carcinoma with dismal survival outcomes. A major barrier in the field has been the relative paucity of human tumors studied. Here we provide an integrated analysis of 3,600 "real-world" SCLC cases. This large cohort allowed us to identify new recurrent alterations and genetic subtypes, including STK11-mutant tumors (1.7%) and TP53/RB1 wild-type tumors (5.5%), as well as rare cases that were human papillomavirus-positive. In our cohort, gene amplifications on 4q12 are associated with increased overall survival, whereas CCNE1 amplification is associated with decreased overall survival. We also identify more frequent alterations in the PTEN pathway in brain metastases. Finally, profiling cases of SCLC containing oncogenic drivers typically associated with NSCLC demonstrates that SCLC transformation may occur across multiple distinct molecular cohorts of NSCLC. These novel and unsuspected genetic features of SCLC may help personalize treatment approaches for this fatal form of cancer.

SIGNIFICANCE

Minimal changes in therapy and survival outcomes have occurred in SCLC for the past four decades. The identification of new genetic subtypes and novel recurrent mutations as well as an improved understanding of the mechanisms of transformation to SCLC from NSCLC may guide the development of personalized therapies for subsets of patients with SCLC. This article is highlighted in the In This Issue feature, p. 1501.

[Study on the Biological Function of Abemecilib in Inhibiting the Proliferation, Invasion and Migration of Small Cell Lung Cancer with High c-Myc Expression]

BACKGROUND

Small cell lung cancer (SCLC) with high c-Myc expression is prone to relapse and metastasis, leading to extremely low survival rate. Cyclin-dependent kinases 4 and 6 (CDK4/6) inhibitor Abemaciclib plays a key role in the treatment of tumors, but the effects and mechanisms on SCLC remain unclear. This study was to analyze the effect and molecular mechanism of Abemaciclib in inhibiting proliferation, migration and invasion of SCLC with high c-Myc expression, with a view to expanding a new direction for reducing the recurrence and metastasis.

METHODS

Proteins interacting with CDK4/6 were predicted using the STRING database. The expressions of CDK4/6 and c-Myc in 31 cases of SCLC cancer tissues and paired adjacent normal tissues were analyzed by immunohistochemistry. The effects of Abemaciclib on the proliferation, invasion and migration of SCLC were detected by CCK-8, colony formation assay, Transwell and migration assay. Western blot was used to detect the expressions of CDK4/6 and related transcription factors. Flow cytometry was used to analyze the effects of Abemaciclib on the cell cycle and checkpoint of SCLC.

RESULTS

The expression of CDK4/6 was associated with c-Myc by STRING protein interaction network. c-Myc can directly modalize achaete-scute complex homolog 1 (ASCL1), neuronal differentiation 1 (NEUROD1) and Yes-associated protein 1 (YAP1). Moreover, CDK4 and c-Myc regulate the expression of programmed cell death ligand 1 (PD-L1). Immunohistochemistry showed that the expressions of CDK4/6 and c-Myc in cancer tissues were higher than those in adjacent tissues(P<0.0001). CCK-8, colony formation assay, Transwell and migration assay verified that Abemaciclib could effectively inhibit the proliferation, invasion and migration of SBC-2 and H446OE(P<0.0001). Western blot analysis further showed that Abemaciclib not only inhibited CDK4 (P<0.05) and CDK6 (P<0.05), but also affected c-Myc (P<0.05), ASCL1 (P<0.05), NEUROD1 (P<0.05) and YAP1 (P<0.05), which are related to SCLC invasion and metastasis. Flow cytometry showed that Abemaciclib not only inhibited the cell cycle progression of SCLC cells (P<0.0001), but also significantly increased PD-L1 expression on SBC-2 (P<0.01) and H446OE (P<0.001).

CONCLUSIONS

Abemaciclib significantly inhibits the proliferation, invasion, migration and cell cycle progression of SCLC by inhibiting the expressions of CDK4/6, c-Myc, ASCL1, YAP1 and NEUROD1. Abemaciclib can also increase the expression of PD-L1 in SCLC.

Primary head and neck cancer cell cultures are susceptible to proliferation of Epstein-Barr virus infected lymphocytes

BACKGROUND

New concepts for a more effective anti-cancer therapy are urgently needed. Experimental flaws represent a major counter player of this development and lead to inaccurate and unreproducible data as well as unsuccessful translation of research approaches into clinics. In a previous study we have created epithelial cell cultures from head and neck squamous cell carcinoma (HNSCC) tissue.

METHODS

We characterize primary cell populations isolated from human papillomavirus positive HNSCC tissue for their marker expression by RT-qPCR, flow cytometry, and immunofluorescence staining. Their sensitivity to MDM2-inhibition was measured using cell viability assays.

RESULTS

Primary HNSCC cell cultures showed the delayed formation of spheroids at higher passages. These spheroids mimicked the morphology and growth characteristics of other established HNSCC spheroid models. However, expression of epithelial and mesenchymal markers could not be detected in these cells despite the presence of the HNSCC stem cell marker aldehyde dehydrogenase 1 family member A1. Instead, strong expression of B- and T-lymphocytes markers was observed. Flow cytometry analysis revealed a heterogeneous mixture of CD3 + /CD25 + T-lymphocytes and CD19 + B-lymphocytes at a ratio of 4:1 at passage 5 and transformed lymphocytes at late passages (≥ passage 12) with CD45 + CD19 + CD20 + , of which around 10 to 20% were CD3 + CD25 + CD56 + . Interestingly, the whole population was FOXP3-positive indicative of regulatory B-cells (B_regs). Expression of transcripts specific for the Epstein-Barr-virus (EBV) was detected to increase in these spheroid cells along late passages, and this population was vulnerable to MDM2 inhibition. HPV + HNSCC cells but not EBV + lymphocytes were detected to engraft into immunodeficient mice.

CONCLUSIONS

In this study we present a primary cell culture of EBV-infected tumor-infiltrating B-lymphocytes, which could be used to study the role of these cells in tumor biology in future research projects. Moreover, by describing the detailed characteristics of these cells, we aim to caution other researchers in the HNSCC field to test for EBV-infected lymphocyte contaminations in primary cell cultures ahead of further experiments. Especially researchers who are interested in TIL-based adopted immunotherapy should exclude these cells in their primary tumor models, e.g. by MDM2-inhibitor treatment. BI-12-derived xenograft tumors represent a suitable model for in vivo targeting studies.

Effect of pleural invasion on survival of patients with small cell lung cancer: Propensity score analysis and nomogram establishment based on the SEER database

Objectives

Pleural invasion (PI) is identified as an adverse prognostic factor for non-small cell lung cancer (NSCLC), but its value in small cell lung cancer (SCLC) remains unclear. We aimed to evaluate the survival effect of PI on overall survival (OS) in SCLC, meanwhile, we established a predictive nomogram based on related risk factors for OS in SCLC patients with PI.

Methods

We extracted the data of patients diagnosed with primary SCLC between 2010 and 2018 from the Surveillance, Epidemiology, and End Results (SEER) database. The propensity score matching (PSM) method was used to minimize the baseline difference between the non-PI and PI groups. Kaplan-Meier curves and the log-rank test were used for survival analysis. Univariate and multivariate Cox regression analyses were applied to identify the independent prognostic factors. Randomly divided the patients with PI into training (70%) and validation (30%) cohorts. A prognostic nomogram was established based on the training cohort and was evaluated in the validation cohort. The C-index, receiver operating characteristic curves (ROC), calibration curves, and decision curve analysis (DCA) were applied to assess the performance of the nomogram.

Results

A total of 1,770 primary SCLC patients were enrolled, including1321patients with non-PI and 449 patients with PI. After PSM, the 387 patients in the PI group matched the 387 patients in the non-PI group. By Kaplan-Meier survival analysis, we observed the exact beneficial effect of non-PI on OS in both original and matched cohorts. Multivariate Cox analysis showed similar results to demonstrate a statistically significant benefit for patients with non-PI in both original and matched cohorts. Age, N stage, M stage, surgery, radiotherapy, and chemotherapy were independent prognostic factors for SCLC patients with PI. The C-index of the nomogram in the training and validation cohort was 0.714 and 0.746, respectively. The ROC curves, calibration curves, and DCA curves also demonstrated good predictive performance in the training and validation cohorts of the prognostic nomogram.

Conclusion

Our study shows that PI is an independent poor prognostic factor for SCLC patients. The nomogram is a useful and reliable tool to predict the OS in SCLC patients with PI. The nomogram can provide strong references to clinicians to facilitate clinic decisions.

Potential predictors of immunotherapy in small cell lung cancer

Lung cancer is one of the leading causes of cancer-related deaths worldwide, with small cell lung cancer (SCLC) having the worst prognosis. SCLC is diagnosed late in the disease's progression, limiting treatment options. The most common treatment for SCLC is chemotherapy. As the disease progresses, immunotherapy, most commonly checkpoint inhibitor medication, becomes more important. Efforts should be made in the development of immunotherapy to map specific biomarkers, which play a role in properly assigning a type of immunotherapy to the right cohort of patients, where the benefits outweigh any risks or adverse effects. The objective of this review was to provide a thorough assessment of current knowledge about the nature of the tumor process and treatment options for small cell lung cancer, with a focus on predictive biomarkers. According to the information obtained, the greatest potential, which has already been directly demonstrated in some studies, has characteristics such as tumor microenvironment composition, tumor mutation burden, and molecular subtyping of SCLC. Several other aspects appear to be promising, but more research, particularly prospective studies on a larger number of probands, is required. However, it is clear that this field of study will continue to expand, as developing a reliable method to predict immunotherapy response is a very appealing goal of current medicine and research in the field of targeted cancer therapy.

Pathological Stage N1 Limited-Stage Small-Cell Lung Cancer Patients Can Benefit From Surgical Resection

PURPOSE

Surgery is controversial in limited-stage small-cell lung cancer (LS-SCLC) (except for T1-2, N0M0). This study aimed to analyze the survival of LS-SCLC patients with proximal lobe (N1) lymph node metastases after surgery and appropriate postoperative adjuvant treatment.

PATIENTS AND METHODS

We reviewed and followed up medical history and survival data of LS-SCLC patients from June 2007 to June 2016, and a total of 68 pathological stage N1 (p-N1) patients who underwent surgical resection and 71 clinical-stage N1 (c-N1) patients who received chemoradiotherapy were included in the final analysis.

RESULTS

The median follow-up of all the patients was 99.30 months. The median disease-free survival (DFS) of the surgery group was 13.567 months, and the median overall survival (OS) of the surgery and chemoradiotherapy groups were 29.600 months and 21.133 months (P-value < .001), respectively. The 2- and 5-year survival rates of the surgery group were 55.9% and 33.7%, and the 2- and 5-year survival rates of the chemoradiotherapy group were 39.8% and 9.4%, respectively. Meanwhile, postoperative thoracic radiotherapy appeared to be associated with a good prognosis (median OS 36.400 vs. 21.333 months, P-value .048), as did prophylactic cranial irradiation (median OS 50.867 vs. 22.600 months, P-value .007) in the surgery group.

CONCLUSIONS

Surgery may benefit patients with p-N1 SCLC, and in combination with appropriate postoperative adjuvant treatment, surgery may be a new therapeutic modality for SCLC.

cfDNA methylome profiling for detection and subtyping of small cell lung cancers

Small cell lung cancer (SCLC) is characterized by morphologic, epigenetic and transcriptomic heterogeneity. Subtypes based upon predominant transcription factor expression have been defined that, in mouse models and cell lines, exhibit potential differential therapeutic vulnerabilities, with epigenetically distinct SCLC subtypes also described. The clinical relevance of these subtypes is unclear, due in part to challenges in obtaining tumor biopsies for reliable profiling. Here we describe a robust workflow for genome-wide DNA methylation profiling applied to both patient-derived models and to patients' circulating cell-free DNA (cfDNA). Tumor-specific methylation patterns were readily detected in cfDNA samples from patients with SCLC and were correlated with survival outcomes. cfDNA methylation also discriminated between the transcription factor SCLC subtypes, a precedent for a liquid biopsy cfDNA-methylation approach to molecularly subtype SCLC. Our data reveal the potential clinical utility of cfDNA methylation profiling as a universally applicable liquid biopsy approach for the sensitive detection, monitoring and molecular subtyping of patients with SCLC.

Unraveling tumor microenvironment of small-cell lung cancer: implications for immunotherapy

Small-cell lung cancer (SCLC) is an aggressive lung cancer subtype and its first-line treatment has remained unchanged for decades. In recent years, immunotherapy has emerged as a therapeutic strategy for tumor treatment, whereas, patients with SCLC exhibit poor overall responses to immunotherapy alone, which highlights the necessity for combinatorial approaches. The tumor microenvironment (TME), an integral component in cancer, is widely implicated in tumorigenesis and tumor metastasis. The interactions of various cells within TME shape the adverse conditions of the tumor microenvironment (characterized by hypoxia, nutrient restriction, and acidity) and are considered responsible for the modest therapeutic responses to immunotherapy. Several studies have suggested that adverse TME can regulate immune cell activation and function. However, the specific regulatory mechanisms and their implications on immunotherapy remain unclear. Thus, it is worth unraveling the characteristics of TME and its impact on antitumor immunity, in the hope of devising novel strategies to reinforce immunotherapeutic effects on SCLC. In this review, we firstly elaborate on the immune landscape of SCLC and the formation of three remarkable characteristics in TME, as well as the interaction among them. Next, we summarize the latest findings regarding the impacts of adverse TME on immune cells and its targeted therapy in SCLC. Finally, we discuss the ongoing trials in combination therapy and potential directions of SCLC therapy. Collectively, the findings combined here are expected to aid the design of trials for combining immunotherapy with therapy targeting the TME of SCLC.

Accurate treatment of small cell lung cancer: Current progress, new challenges and expectations

Small cell lung cancer (SCLC) is a deadly disease with poor prognosis. Fast growing speed, inclination to metastasis, enrichment in cancer stem cells altogether constitute its aggressive nature. In stark contrast to non-small cell lung cancer (NSCLC) that strides vigorously on the road to precision oncology, SCLC has been on the embryonic path to achieve effective personalized treatments. The survival of patients with SCLC have not been improved greatly, which could be possibly due to our inadequate understanding of genetic alterations of SCLC. Recently, encouraging effects have been observed in patients with SCLC undergoing immunotherapy. However, exciting results have only been observed in a small fraction of patients with SCLC, warranting biomarkers predictive of responses as well as novel therapeutic strategies. In addition, SCLC has previously been viewed to be homogeneous. However, perspectives have been changed thanks to the advances in sequencing techniques and platforms, which unfolds the complex heterogeneity of SCLC both genetically and non-genetically, rendering the treatment of SCLC a further step forward into the precision era. To outline the road of SCLC towards precision oncology, we summarize the progresses and achievements made in precision treatment in SCLC in genomic, transcriptomic, epigenetic, proteomic and metabolic dimensions. Moreover, we conclude relevant therapeutic vulnerabilities in SCLC. Clinically tested drugs and clinical trials have also been demonstrated. Ultimately, we look into the opportunities and challenges ahead to advance the individualized treatment in pursuit of improved survival for patients with SCLC.

YES1 is a druggable oncogenic target in Small Cell Lung Cancer

RATIONALE

Small cell lung cancer (SCLC) is an extremely aggressive subtype of lung cancer without approved targeted therapies. Here we identified YES1 as a novel targetable oncogene driving SCLC maintenance and metastasis.

OBJECTIVES

To investigate the role of YES1 in SCLC prognosis and evaluate its inhibition as a new therapeutic strategy.

METHODS

Association between YES1 levels and prognosis was evaluated in SCLC clinical samples. In vitro functional experiments for proliferation, apoptosis, cell cycle and cytotoxicity were performed. Genetic and pharmacological inhibition of YES1 was evaluated in vivo in cell-/patient-derived xenografts (PDXs) and in metastasis. YES1 levels were evaluated in mouse and patients' plasma-derived exosomes MEASUREMENTS AND MAIN RESULTS: Overexpression or gain/amplification of YES1 was identified in 31% and 26% of cases, respectively, across molecular subgroups, and was found as an independent predictor of poor prognosis. Genetic depletion of YES1 dramatically reduced cell proliferation, 3D organoid formation, tumor growth and distant metastasis, leading to extensive apoptosis and tumor regressions. Mechanistically, YES1-inhibited cells showed alterations in the replisome and DNA repair processes, that conferred sensitivity to irradiation. Pharmacological blockade with the novel YES1 inhibitor CH6953755 or Dasatinib induced significant anti-tumor activity in organoid models and cell-/patient-derived xenografts. YES1 protein was detected in plasma exosomes from patients and mouse models, with levels matching those of tumors, suggesting that circulating YES1 could represent a biomarker for patient selection/monitoring.

CONCLUSIONS

Our results provide evidence that YES1 is a new druggable oncogenic target and biomarker to advance the clinical management of a subpopulation of SCLC patients.

Extracellular vesicles containing PD-L1 contribute to CD8+ T-cell immune suppression and predict poor outcomes in small cell lung cancer

Programmed death ligand-1 (PD-L1) is expressed on the surface of tumor cells and binds to programmed cell death protein-1 (PD1) on the surface of T cells, leading to cancer immune evasion via inhibition of T-cell function. One of the characteristics of small cell lung cancer (SCLC) is its ineffective anti-tumor immune response and highly immunosuppressive status in the tumor microenvironment. SCLC cells have been shown to generate extracellular vesicles (EVs), which may play an important role in tumor progression. We thus hypothesized that SCLC EVs may be important mediators of immunosuppression and that PD-L1 could play a role. Herein, we showed that PD-L1 was expressed on the surface of SCLC-derived EVs, with the potential to directly bind to PD1. Experimentally, we further showed that EVs secreted by SCLC cells can inhibit CD8+ T-cell activation and cytokine production in vitro in response to T-cell receptor stimulation. Importantly, an anti-PD-L1 blocking antibody significantly reversed the EV-mediated inhibition of CD8+ T-cell activation. Furthermore, we performed a retrospective study of patients with SCLC to determine the prognostic value of PD-L1 harvested from plasm circulating EVs. The results showed that EVs containing PD-L1 was an independent prognostic factor and significantly correlated with progression-free survival. Together, these results indicate that EVs containing PD-L1 can be served as a diagnostic biomarker for predicting the effectiveness of therapy, as well as a new strategy to enhance T-cell-mediated immunotherapy against SCLC cancers.

Infiltrating T lymphocytes in the tumor microenvironment of small cell lung cancer: a state of knowledge review

Immune checkpoint inhibitors (ICIs) have brought new hope for the treatment of patients with small cell lung cancer (SCLC) over the past decades. However, the overall response rate is limited, and is lower than that in non-small cell lung cancer (NSCLC). This is in part because of the lack of pre-existing tumor-infiltrating T lymphocytes (TITLs), especially cytotoxic T cells (CTLs), in the SCLC tumor microenvironment (TME), resulting in insufficient anti-tumor immune response. To unleash the full potential of ICIs, the trafficking and infiltration of TITLs to the tumor is necessary and tightly regulated, the highly immunosuppressive tumor microenvironment blunts the infiltration and function of TITLs that reach the tumor in SCLC. Here, we review the characteristics of TITLs, the effects of various factors on T cell infiltration, and possible strategies to restore or promote T cell infiltration in the TME of SCLC.

Small-Cell Lung Cancer Long-Term Survivor Patients: How to Find a Needle in a Haystack?

Small-cell lung cancer (SCLC) is an aggressive malignancy characterized by a rapid progression and a high resistance to treatments. Unlike other solid tumors, there has been a scarce improvement in emerging treatments and survival during the last years. A better understanding of SCLC biology has allowed for the establishment of a molecular classification based on four transcription factors, and certain therapeutic vulnerabilities have been proposed. The universal inactivation of TP53 and RB1, along with the absence of mutations in known targetable oncogenes, has hampered the development of targeted therapies. On the other hand, the immunosuppressive microenvironment makes the success of immune checkpoint inhibitors (ICIs), which have achieved a modest improvement in overall survival in patients with extensive disease, difficult. Currently, atezolizumab or durvalumab, in combination with platinum–etoposide chemotherapy, is the standard of care in first-line setting. However, the magnitude of the benefit is scarce and no predictive biomarkers of response have yet been established. In this review, we describe SCLC biology and molecular classification, examine the SCLC tumor microenvironment and the challenges of predictive biomarkers of response to new treatments, and, finally, assess clinical and molecular characteristics of long-term survivor patients in order to identify possible prognostic factors and treatment vulnerabilities.

Identification of a prognostic immune-related signature for small cell lung cancer

Purpose

As a subgroup of lung cancer, small cell lung cancer (SCLC) is characterized by a short tumor doubling time, high rates of early occurred distant cancer spread, and poor outcomes. Despite its exquisite sensitivity to chemotherapy and radiotherapy, acquired drug resistance and tumor progression are typical. This study aimed to develop a robust signature based on immune‐related genes to predict the outcome of patients with SCLC.

Methods

The expression data of 77 SCLC patients from George's cohort were divided into training set and testing set, and 1534 immune‐related genes from ImmPort database were used to generate and validate the signature. Cox proportional hazards and the Kaplan–Meier analysis were used for developing and testing the prognostic signature. Single‐sample gene set enrichment analysis was used to determine immune cell infiltration phenotypes.

Results

A 10‐gene model comprising NR3C1, NR1D2, TANK, ARAF, HDGF, INHBE, LRSAM1, PLXNA1, PML, and SP1 with the highest frequency after 1000 interactions, was chosen to construct immune‐related signature. This signature showed robust predictive value for SCLC patients’ survival in both training and testing sets. This signature was weakly associated with the clinic pathological values like TNM stage. Furthermore, patients with low risk presented with activation of immune signal pathways, and specific immune cell infiltration with high levels of CD56^bright NK cells but low levels of CD8⁺ T cells, mast cells, and helper T cells.

Conclusion

The present study developed immune‐related signature that may help predict the prognosis of SCLC patients, which reflects an unappreciated level of heterogeneity of immunophenotype associated with diverse prognosis for specific subsets in this highly lethal cancer type.

CCR2 and PTPRC are regulators of tumor microenvironment and potential prognostic biomarkers of lung adenocarcinoma

Background

Tumor microenvironment (TME) plays an essential role in lung adenocarcinoma (LUAD) development and metastasis. With the development of TME research, it has been proved that differences in tumor-infiltrating immune cells (TICs) and gene expression profile are related to the prognosis of cancer. The aim of our study was to identify key genes affecting immune state in TME of LUAD.

Methods

The RNA-seq data and clinical characteristics of 594 LUAD patients were downloaded from the TCGA database. ImmuneScore, StromalScore and ESTIMATEScore of each LUAD sample were calculated using ESTIMATE algorithm. Based on the median of different scores, LUAD samples were divided into high and low score groups. Differentially expressed genes (DEGs) between groups were obtained, and univariate Cox regression analysis and protein-protein interaction (PPI) network were used to screen the shared DEGs generating in the intersection analysis. Finally, the CIBORSORT algorithm was performed to calculate the relative contents of TICs for each LUAD sample, and the correlation analysis between TICs and key genes was used to determine the influence of key genes to the TME.

Results

In the presented study, we found that three different scores were positively correlated with the prognosis of LUAD patients, and correlation analysis showed the different scores were closely related to tumor progression and metastasis. After performing the intersection analysis, a total of 585 up-regulated and 107 down-regulated DEGs between the high and low score groups were obtained, all of which were enriched in immune-related functions. Having used univariate COX regression analysis and PPI network, the key genes, CCR2 and PTPRC, affecting the immune status of TME and the prognosis of LUAD were acquired. Analysis based on the CIBERSORT algorithm suggested that CCR2 and PTPRC were correlated with a variety of TICs, and closely related to the clinical characteristics of the LUAD patients.

Conclusions

Our research showed that CCR2 and PTPRC may be potential prognostic markers in LUAD, which may affect the function of γδT cells and other immune cells by participating in the regulation of TME immune state.

Propensity score matched analysis for the role of surgery in stage Ⅲ small cell lung cancer based on the eighth edition of the TNM classification: a population study of the US SEER database and a Chinese hospital

OBJECTIVE

Patients with very early stage small cell lung cancer (SCLC) can benefit from surgery. However, the role of surgery in local advanced SCLC patients remains controversial. We designed this study to investigate the role of surgery on survival of this subset population.

METHODS

The included patients were identified from the Surveillance, Epidemiology, and End Results SEER database from 1998 to 2016 and Shanghai Chest Hospital of China from 2009 to 2016. Propensity score matching(PSM) was used to balance clinical bias. The overall survival (OS) and lung cancer-specific survival (LCSS) were compared by the Kaplan-Meier analysis. Cox proportional hazards regression was used to identify factors associated with survival.

RESULTS

Among the 3005 stage Ⅲ patients, 570 (18.97%) patients underwent surgery. Compared with non-surgical group, patients undergoing surgery were more likely to be male, had smaller tumor size, mediastinal lymph node involvement and lower pathologic stage. The Kaplan-Meier analysis showed that surgical patients had a better OS and LCSS before and after PSM. 418 surgical patients were well matched with non-surgical patients. In matched surgical group, there were 224 (53.59%) patients who underwent lobectomy (LB), 147 (35.17%) patients who received sublobectomy (SLB), 31 (7.41%) patients who underwent pneumonectomy and 16 (3.83%) patients with unknown surgery type. The 5-year OS of the 4 subgroups were 28.80%, 12.50%, 8.70% and 13.50%, respectively (P = 0.002). In a multivariable Cox model, SLB (hazard ratio, 1.53; 95%CI, 1.20-1.96; P = 0.001) and pneumonectomy (hazard ratio, 1.72; 95%CI, 1.12-2.65; P = 0.013) were associated with worse OS compared with LB.

CONCLUSION

Surgical resection significantly improved OS and LCSS of stage Ⅲ SCLC patients in our study. Furthermore, LB had advantage over other surgery type but further exploration in larger prospective clinical trials is needed.

What Are the Biomarkers for Immunotherapy in SCLC?

Small-cell lung cancer (SCLC) is an aggressive malignancy that exhibits a rapid doubling time, a high growth fraction, and the early development of widespread metastases. The addition of immune checkpoint inhibitors to first-line chemotherapy represents the first significant improvement of systemic therapy in several decades. However, in contrast to its effects on non-SCLC, the advantageous effects of immunotherapy addition are modest in SCLC. In particular, only a small number of SCLC patients benefit from immune checkpoint inhibitors. Additionally, biomarkers selection is lacking for SCLC, with clinical trials largely focusing on unselected populations. Here, we review the data concerning the major biomarkers for immunotherapy, namely, programmed death ligand 1 expression and tumour mutational burden. Furthermore, we explore other potential biomarkers, including the role of the immune microenvironment in SCLC, the role of genetic alterations, and the potential links between neurological paraneoplastic syndromes, serum anti-neuronal nuclear antibodies, and outcomes in SCLC patients treated with immunotherapy.

Impact of Adjuvant Therapy on Survival in Surgically Resected Limited-Stage Small Cell Lung Cancer

Background

Data on efficacy of adjuvant therapy for surgically resected small cell lung cancer are scant. This study was determined to reveal the survival benefits of different adjuvant treatment modalities for limited-stage small cell lung cancer patients following surgical resection.

Methods

Data of patients with histologically confirmed small cell lung cancer after surgical resection were collected from November 2006 to June 2019. Survival analyses were calculated by Kaplan–Meier method, with log-rank test to evaluate statistical significance. Prognostic factors were identified by multivariate analysis using cox proportional hazards model. Further survival analysis and cox regression analysis stratified by clinicopathologic features were conducted to evaluate the survival benefits of different adjuvant treatment modalities.

Results

In total, 153 out of 157 patients were analyzed. Multivariate analysis showed male sex, lymph node metastasis, residual tumor, VPI and non-adjuvant therapy were independently associated with poor prognosis. Subgroup analyses revealed both adjuvant chemotherapy and adjuvant chemoradiotherapy were significantly associated with superior survival for stage pT2-4 (HR=0.176, 95%CI:0.053-0.578, p=0.004; and HR=0.115, 95%CI:0.033-0.405, p=0.001) and pure SCLC patients (HR=0.182, 95%CI:0.067-0.494, p=0.001; and HR=0.181, 95%CI:0.071-0.465, p<0.001). For pN0 patients, adjuvant chemotherapy was associated with better survival (HR=0.219, 95%CI:0.054-0.891, p=0.034), while adjuvant chemoradiotherapy was associated with improved survival for pN+ patients (HR=0.324, 95%CI:0.138-0.760, p=0.010).

Conclusions

For patients without pathologic lymph node metastasis, there is a survival benefit with adjuvant chemotherapy. However, for patients with pathologic lymph node metastasis, adjuvant chemoradiotherapy might achieve a significant survival benefit. Further prospective studies are needed to validate the results.

Octogenarians may benefit from stage-specific small cell lung cancer treatment

BACKGROUND

Our study investigates treatment profiles in octogenarian patients with small cell lung cancer (SCLC) and assesses each treatment's role in a stage-specific manner.

METHODS

Patient data from individuals with SCLC aged 80 years and older between 1988 and 2015 in the Surveillance, Epidemiology, and End Results Program (SEER) database were extracted. Cancer-specific survival (CSS) between patients with no treatment and different treatment groups were compared by the Kaplan-Meier method, with stratifications by stage. Cox Proportional Hazard model further identified independent prognostic factors.

RESULTS

A total of 7,290 patients were included in this study. Notably, 3,358 (46.1%) patients did not receive active treatment. Compared with the no active treatment group, the CSS of patients who received treatment was significantly improved (median 6 vs. 0 months, P<0.001) and further validated in stage subgroups. Chemotherapy combined with local therapy was associated with the best CSS in regional and distant disease stages, with the hazard ratios (HR) and 95% confidence intervals (CI) being 0.30 (0.26-0.34) and 0.27 (0.25-0.30), respectively. Local therapy only appeared to confer better oncological outcomes (HR =0.33; 95% CI: 0.25-0.42) than chemotherapy only (HR =0.37; 95% CI: 0.29-0.47) in the localized disease stage.

CONCLUSIONS

Although nearly half of octogenarians with SCLC did not receive active treatment in the real clinical setting, these patients may benefit from treatment. Chemotherapy combined with local therapy may provide the best treatment choice in octogenarians with advanced SCLC, while local therapy appears to play a more critical role in treating those with early-stage disease.

mRNA Network: Solution for Tracking Chemotherapy Insensitivity in Small-Cell Lung Cancer

Background

Small-cell lung cancer (SCLC) has poor prognosis and is prone to drug resistance. It is necessary to search for possible influencing factors for SCLC chemotherapy insensitivity. Therefore, we proposed an mRNA network to track the chemotherapy insensitivity in SCLC.

Methods

Six samples of patients with SCLC were recruited for RNA sequencing. TopHat2 and Cufflinks were used to make differential analysis. Functional analysis was applied as well. Finally, multidimensional validation was applied for verifying the results we obtained by experiment.

Results

This study was a trial of drug resistance in 6 SCLC patients after first-line chemotherapy. The top 10 downregulated genes differentially expressed in the chemo-insensitive group were SERPING1, DRD5, PARVG, PRAME, NKX1-1, MCTP2, PID1, PLEKHA4, SPP1, and SLN. Cell-cell signaling by Wnt (p=6.98E - 21) was the most significantly enriched GO term in biological process, while systemic lupus erythematosus (p=6.97E - 10), alcoholism (p=1.01E - 09), and transcriptional misregulation in cancer (p=0.00227988) were the top three ones of KEGG pathways. In multiple public databases, we also highlighted and verified the vital role of glycolysis/gluconeogenesis pathway and corresponding genes in chemo-insensitivity in SCLC.

Conclusion

Our study confirmed some SCLC chemotherapy insensitivity-related genes, biological processes, and pathways, thus constructing the chemotherapy-insensitive network for SCLC.

Patterns of Recurrence and Survival Rate After Complete Resection of Pathological Stage N2 Small-Cell Lung Cancer

The benefits of surgical resection for patients with stage N2 limited-disease small-cell lung cancer (LD-SCLC) remain controversial. This retrospective study analyzed the survival and recurrence patterns of the patients diagnosed with pathological N2 (p-N2) LD-SCLC after radical resection. A total of 171 p-N2 LD-SCLC patients who underwent radical pulmonary resection and systematic lymphadenectomies at Shanghai Chest Hospital from July 2005 to June 2015 were enrolled. The influence of the mediastinal lymph node status (single or multiple nodes, single- or multiple-station) on the survival and recurrence patterns was retrospectively analyzed. The main recurrence sites were outside the chest cavity (54.8%) and hematogenous metastasis (67.4%). The bone and liver as initial recurrence sites had a poor prognosis, with a median overall survival (OS) of 13.100 months and 11.900 months, respectively. The median disease-free survival (DFS) of patients diagnosed with single and multiple p-N2 after surgery were 19.233 and 9.367 months (P = 0.001), and the median OS were 43.033 and 17.100 months (P < 0.001), respectively. In conclusion, recurrence occurred in the form of hematogenous metastasis mostly in the extra-thoracic part. Interestingly, patients diagnosed with single p-N2 benefited from radical resection. Surgery may be a treatment option regardless of the T stage if N2 SCLC with a single metastatic lymph node can be identified preoperatively.

Neuron - specific enolase predicts the prognosis in advanced small cell lung cancer patients treated with first-line PD-1/PD-L1 inhibitors

There has been no effective biomarker for small cell lung cancer (SCLC) patients with first-line immune checkpoint inhibitors (ICIs) treatment. The predictive value of neuron-specific enolase (NSE) in this cohort remains unclear.The medical records of 254 consecutive SCLC patients receiving programmed cell death receptor-1/programmed cell death-ligand 1 (PD-1/PD-L1) inhibitors were compiled from January 2015 to October 2020 in Chinese PLA General Hospital. Survival analysis was performed to explore the prognostic role of NSE at baseline and 3 weeks post treatment.One hundred two advanced SCLC patients treated with first-line PD-1/PD-L1 inhibitors were enrolled in this study. Normal baseline NSE levels were correlated with significantly prolonged progression-free survival (PFS, median: 8.7 vs 4.7 months, P = .006) and overall survival (OS, median: 23.8 vs 15.2 months, P = .014) compared with elevated baseline NSE levels, so as for normal NSE levels at 3 weeks with prolonged PFS (median PFS: 8.4 vs 4.5 months, P = .0002) and OS (median OS: 23.3 vs 7.4 months, P < .0001). Intriguingly, elevated NSE levels at 3 weeks were associated with shorter PFS (median PFS: 4.5 vs 5.8 months, P = .04) and OS (median OS: 5.5 vs 14.7 months, P < .0001) compared with normal NSE levels in the elevated baseline NSE subgroup. Most subgroup analyses stratified by clinical characteristics confirmed the prognostic value of baseline NSE level.Elevated NSE levels at baseline and 3 weeks were associated with worse prognosis in advanced SCLC patients receiving first-line ICIs treatment. NSE level might be applied as a useful prognostic tool for SCLC patients with immunotherapy.

Effect of surgery on survival in patients with stage III N2 small cell lung cancer: propensity score matching analysis and nomogram development and validation

Background

The standard treatment of stage III N2 small cell lung cancer (SCLC) is concurrent chemoradiation, and surgery is not recommended. This study was aimed to evaluate whether surgery has survival benefits in patients with stage III N2 SCLC and investigate the factors influencing survival of surgery.

Methods

Patients diagnosed with stage T1-4N2M0 SCLC from 2004 to 2015 were selected from the Surveillance Epidemiology End Results database. Propensity score matching (PSM) was used to balance confounders between patients who underwent surgery and those treated with radiation and/or chemotherapy. We compared overall survival (OS) of the two groups using Kaplan-Meier curves and a Cox proportional hazard model. We also identified prognostic factors in patients with surgical resection, and a nomogram was developed and validated for predicting postoperative OS.

Results

−A total of 5576 patients were included in the analysis; of these, 211 patients underwent surgery. PSM balanced the differences between the two groups. The median OS was longer in the surgery group than in the non-surgery group (20 vs. 15 months; p = 0.0024). Surgery was an independent prognostic factor for longer OS in the multivariate Cox regression analysis, and subgroup analysis revealed a higher survival rate in T1 stage patients treated with surgery (hazard ratio = 0.565, 95% confidence interval: 0.401–0.798; p = 0.001). In patients who underwent surgery, four prognostic factors, including age, T stage, number of positive lymph nodes, and radiation, were selected into nomogram development for predicting postoperative OS. C-index, decision curve analyses, integrated discrimination improvement, and time-dependent receiver operating characteristics showed better performance in nomogram than in the tumor-node-metastasis staging system. Calibration plots demonstrated good consistency between nomogram predicted survival and actual observed survival. The patients were stratified into three different risk groups by prognostic scores and Kaplan-Meier curves showed significant difference between these groups.

Conclusions

These results indicate that surgery can prolong survival in patients with operable stage III N2 SCLC, particularly those with T1 disease. A nomogram that includes age, T stage, number of positive lymph nodes, and radiation can be used to predict their long-term postoperative survival.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-021-02364-6.

Prognostic factors of patients with small cell lung cancer after surgical treatment

Background

The current National Comprehensive Cancer Network guidelines recommend surgical treatment for patients with stages I–IIA small cell lung cancer (SCLC), but it still cannot deny the effect of surgical treatment on other limited-stage SCLC. Although more advanced diagnostic methods are now used for the diagnosis and classification of SCLC, the selection of surgical candidates is still arbitrary.

Methods

Data were collected from patients with SCLC who underwent surgery at the First Affiliated Hospital of Zhengzhou University from January 2011 to January 2021. Kaplan-Meier method was used to calculate cumulative survival curves, and log-rank test was used to evaluate differences among different subgroups. The Cox proportional hazard regression model was used to assess the predictive power of the variables for prognosis and survival.

Results

Smoking index, surgical resection method, TNM stage of postoperative pathology, and postoperative chemotherapy were significantly correlated with postoperative survival (P<0.05), which were independent predictors for postoperative survival. Patients with a smoking index >800 had a higher risk of death after surgery [hazard ratio (HR): 7.050, 95% confidence interval (CI): 3.079–16.143, P<0.001]. Compared with patients who underwent pulmonary lobectomy, those who underwent other pneumoresections (e.g., wedge resection, segmental resection, sleeve resection) had an increased risk of death (HR: 2.822, 95% CI: 1.030–7.734, P=0.044). Compared with stage I patients, stage II and stage III patients had an increased risk of death, with HRs of 6.039 and 3.145, respectively. Compared with those who received ≤4 courses of postoperative chemotherapy, those who received >4 courses of postoperative chemotherapy had reduced postoperative mortality risk (HR: 0.211, 95% CI: 0.097–0.459, P<0.001).

Conclusions

A high smoking index suggests worse prognosis; therefore, patients who smoke should be advised to quit smoking. Compared with stage II and stage III patients, surgical treatment is recommended for stage I SCLC patients. TNM staging, especially N staging, should be evaluated prior to surgery. Pulmonary lobectomy with mediastinal lymph node dissection should be the preferred surgical treatment for patients with SCLC. Patients should receive at least 5 courses of adjuvant chemotherapy after surgery.

Human leukocyte antigen class II-based immune risk model for recurrence evaluation in stage I-III small cell lung cancer

Background

Immunotherapy has revolutionized therapeutic patterns of small cell lung cancer (SCLC). Human leukocyte antigen class II (HLA class II) is related to antitumor immunity. However, the implications of HLA class II in SCLC remain incompletely understood.

Materials and methods

We investigated the expression patterns of HLA class II on tumor cells and tumor-infiltrating lymphocytes (TILs) by immunohistochemistry staining and its association with clinical parameters, immune markers, and recurrence-free survival (RFS) in 102 patients with stage I–III SCLC with radical surgery. Additionally, an HLA class II-based immune risk model was established by least absolute shrinkage and selection operator regression. With bioinformatics methods, we investigated HLA class II-related enrichment pathways and immune infiltration landscape in SCLC.

Results

HLA class II on tumor cells and TILs was positively expressed in 9 (8.8%) and 45 (44.1%) patients with SCLC, respectively. HLA class II on TILs was negatively associated with lymph node metastasis and positively correlated with programmed death-ligand 1 (PD-L1) on TILs (p<0.001) and multiple immune markers (CD3, CD4, CD8, FOXP3; p<0.001). Lymph node metastasis (OR 0.314, 95% CI 0.118 to 0.838, p=0.021) and PD-L1 on TILs (OR 3.233, 95% CI 1.051 to 9.95, p=0.041) were independent predictive factors of HLA class II on TILs. HLA class II positivity on TILs prompted a longer RFS (40.2 months, 95% CI 31.7 to 48.7 vs 28.8 months, 95% CI 21.4 to 36.3, p=0.014). HLA class II on TILs, PD-L1 on TILs, CD4, and FOXP3 were enrolled in the immune risk model, which categorized patients into high-risk and low-risk groups and had better power for predicting the recurrence than tumor stage. Pathway enrichment analyses showed that patients with high HLA class II expression demonstrated signatures of transmembrane transportation, channel activity, and neuroactive ligand–receptor interaction. High-risk SCLC patients had a higher proportion of T follicular helper cells (p=0.034) and a lower proportion of activated memory CD4-positive T cells (p=0.040) and resting dendritic cells (p=0.045) versus low-risk patients.

Conclusions

HLA class II plays a crucial role in tumor immune microenvironment and recurrence prediction. This work demonstrates the prognostic and clinical values of HLA class II in patients with SCLC.

Arginase Pathway Markers of Immune-Microenvironment in Thymic Epithelial Tumors and Small Cell Lung Cancer

BACKGROUND

Key regulators of antitumor immunity such as arginase-1 and the adenosine pathway may have an important role in modulating the effect of immunotherapy. Here, we investigated the expression profile of these immune-related biomarkers in thymic epithelial tumors (TETs) and small cell lung cancer (SCLC), 2 solid tumors where immune checkpoint inhibitors have activity.

MATERIALS AND METHODS

Immunohistochemical staining was performed using tissue microarrays of 123 TET (110 thymoma and 13 thymic carcinoma) and 125 SCLC cases. The expression profile of the following immune-related biomarkers was assessed: arginase-1, CD39, CD73, A2AR, PD-L2, and CD15. The expression profile was also correlated with clinical data.

RESULTS

No sample was positive for arginase-1. In the adenosine pathway, the prevalence of positive staining for CD39, CD73, and A2AR was 4.9%, 2.5%, and 69.2%, in TETs and 0%, 1.7%, and 50.8%, in SCLC. The multivariate analysis showed that CD39 expression was significantly associated with worse disease related survival (hazard ratio [HR], 10.36; 95% confidence interval [CI]: 2.01-53.47; P= .005) and a shorter time-to progression (HR, 11.35; 95% CI, 2.11-61.23; P = .005) in TETs. Other biomarkers were not associated with disease related survival or time to progression in TETs. No biomarker was associated with survival in SCLC.

CONCLUSION

Arginase-1 was not detectable in TETs and SCLC. Expression of markers in the adenosine pathway were present in both TETs and SCLC. CD39 expression in tumor cells may identify subsets of patients with TETs with an unfavorable prognosis.

Combinatorial therapy in tumor microenvironment: Where do we stand?

The tumor microenvironment plays a pivotal role in tumor initiation and progression by creating a dynamic interaction with cancer cells. The tumor microenvironment consists of various cellular components, including endothelial cells, fibroblasts, pericytes, adipocytes, immune cells, cancer stem cells and vasculature, which provide a sustained environment for cancer cell proliferation. Currently, targeting tumor microenvironment is increasingly being explored as a novel approach to improve cancer therapeutics, as it influences the growth and expansion of malignant cells in various ways. Despite continuous advancements in targeted therapies for cancer treatment, drug resistance, toxicity and immune escape mechanisms are the basis of treatment failure and cancer escape. Targeting tumor microenvironment efficiently with approved drugs and combination therapy is the solution to this enduring challenge that involves combining more than one treatment modality such as chemotherapy, surgery, radiotherapy, immunotherapy and nanotherapy that can effectively and synergistically target the critical pathways associated with disease pathogenesis. This review shed light on the composition of the tumor microenvironment, interaction of different components within tumor microenvironment with tumor cells and associated hallmarks, the current status of combinatorial therapies being developed, and various growing advancements. Furthermore, computational tools can also be used to monitor the significance and outcome of therapies being developed. We addressed the perceived barriers and regulatory hurdles in developing a combinatorial regimen and evaluated the present status of these therapies in the clinic. The accumulating depth of knowledge about the tumor microenvironment in cancer may facilitate further development of effective treatment modalities. This review presents the tumor microenvironment as a sweeping landscape for developing novel cancer therapies.

The clinical impact of three validated PD-L1 immunohistochemistry assays as a prognostic factor in small cell lung cancer

Background

Evidence of the clinical impact of programmed death-ligand 1 (PD-L1) expression in small cell lung cancer (SCLC) is scarce and conflicting, even though atezolizumab became the first PD-L1 inhibitor approved by the US Food and Drug Administration (FDA) in recent years for the initial treatment of extensive-stage (ES)-SCLC.

Methods

We investigated PD-L1 expression in SCLC tumors using the three validated PD-L1 immunohistochemistry (IHC) assays (SP263, SP142, and 22C3) and assessed the correlation between PD-L1 expression and clinicopathological factors to determine the prognostic value of PD-L1 expression. The three PD-L1 IHC analyses were prospectively used to assess tumor samples of patients with SCLC at diagnosis.

Results

Of the total of 59 patients, 47 patients received the active treatment beyond platinum-based chemotherapy at our institution. PD-L1 expression was positive in 39.0% with SP263, 37.3% with SP142, and 22.0% with 22C3. In a univariate analysis, the positive result of at least one of the three PD-L1 assays and the positive result of the SP142 assay were associated with longer overall survival (OS). A multivariable analysis confirmed that performance status, stage, and the SP142 assay were independent predictors of OS. In subgroup analysis, these results revealed more significant prognostic factors in ES than in limited-stage (LS). In patients with SCLC, especially those with ES, the expression of the SP142 assay is a significant independent prognostic factor.

Conclusions

Although these results need to be further validated in larger cohorts, this information will benefit clinicians and patients in determining the immunotherapy for patients with ES-SCLC.

Toxicities of Immunotherapy for Small Cell Lung Cancer

Small cell lung cancer (SCLC), composing 15–20% of lung cancer, is a fatal disease with extremely poor prognosis. In the past two decades, etoposide platinum doublet chemotherapy remained the only choice of therapy, with disappointing overall survival ≤1 year for the metastatic disease. Novel treatments including immunotherapy are urgently needed and extensively explored. Recently, in two phase III trials, atezolizumab and durvalumab were shown to bring survival benefit to patients. While immunotherapy brings better outcome, it is accompanied by adverse events different from traditional treatments. Although these immune-related adverse events (irAEs) are generally mild and can be managed, some irAEs (myocarditis, pneumonitis) may be severe and even life-threatening. Accompanying with the increasing application of immunotherapy in clinical practice, the irAEs should not be overlooked. In this review, the irAEs profile in clinical trials of immunotherapy for SCLC will be summarized, also its unique features compared with irAEs in other malignancies will be explored. This review may be helpful for the appropriate clinical use of immunotherapy for SCLC.

FOXP3-based immune risk model for recurrence prediction in small-cell lung cancer at stages I-III

BACKGROUND

Immunotherapies may prolong the survival of patients with small-cell lung cancer (SCLC) to some extent. The role of forkhead box protein P3 (FOXP3) in tumor microenvironment (TME) remains controversial. We aimed to examine FOXP3-related expression characteristics and prognostic values and to develop a clinically relevant predictive system for SCLC.

METHODS

We enrolled 102 patients with histologically confirmed SCLC at stages I-III. Through immunohistochemistry, we determined the expression pattern of FOXP3 and its association with other immune biomarkers. By machine learning and statistical analysis, we constructed effective immune risk score models. Furthermore, we examined FOXP3-related enrichment pathways and TME traits in distinct cohorts.

RESULTS

In SCLC, FOXP3 level was significantly associated with status of programmed death-ligand 1 (PD-L1), programmed cell death protein 1 (PD-1), CD4, CD8, and CD3 (p=0.002, p=0.001, p=0.002, p=0.030, and p<0.001). High FOXP3 expression showed longer relapse-free survival (RFS) than the low-level group (41.200 months, 95% CI 26.937 to 55.463, vs 14.000 months, 95% CI 8.133 to 19.867; p=0.008). For tumor-infiltrating lymphocytes (TILs), subgroup analysis demonstrated FOXP3 and PD-1, PD-L1, lymphocyte activation gene-3, CD3, CD4, or CD8 double positive were significantly correlated with longer RFS. We further performed importance evaluation for immune biomarkers, constructed an immune risk score incorporating the top three important biomarkers, FOXP3, TIL PD-L1, and CD8, and found their independently prognostic role to predict SCLC relapse. Better predictive performance was achieved in this immune risk model compared with single-indicator-based or two-indicator-based prediction systems (area under the curve 0.715 vs 0.312-0.711). Then, relapse prediction system integrating clinical staging and immune risk score was established, which performed well in different cohorts. High FOXP3-related genes were enriched in several immune-related pathways, and the close relationships of interleukin-2, CD28, basic excision repair genes MUTYH, POLD1, POLD2, and oxidative phosphorylation related gene cytochrome c oxidase subunit 8A with FOXP3 expression were revealed. Moreover, we found low-immune risk score group had statistically higher activated CD4⁺ memory T cells (p=0.014) and plasma cells (p=0.049) than the high-risk group. The heterogeneity of tumor-infiltrating immune cells might represent a promising feature for risk prediction in SCLC.

CONCLUSION

FOXP3 interacts closely with immune biomarkers on tumor-infiltrating cells in TME. This study highlighted the crucial prognostic value and promising clinical applications of FOXP3 in SCLC.

Identification of Resectable N2 in NSCLC: A Single Center Experience and Review of the SEER Database

Background

Non-small cell lung carcinoma (NSCLC) with ipsilateral and/or subcarinal mediastinal lymphatic spread (N2) is a heterogeneous disease. The role of surgical resection in patients with N2 NSCLC remains controversial and no survival-based definition of “resectable N2” exists. The purpose of this study is to evaluate the factors that potentially affect the survival of N2 NSCLC patients who receive surgical resection and to define “resectable N2” based on the survival benefits.

Methods

Data from the open Surveillance, Epidemiology, and End Results (SEER) database from the National Cancer Institute in the United States were used to construct a nomogram. Patients who received surgery between 2010 and 2015 for N2 NSCLC were included. Independent prognostic factors for survival identified through Cox regression analysis were used to create the nomogram. The C-index, receiver operating characteristics (ROC) analyses, calibration curves, and risk stratification were used to evaluate the nomogram. The nomogram was also validated using data from 222 patients from Peking Union Medical College Hospital (PUMCH). Furthermore, lung cancer–related deaths were compared using competitive risk analysis.

Results

In total, 4267 patients were included in the SEER cohort. Male gender, old age, high T stage and grade, adenosquamous and squamous cell carcinoma, lower lobe and overlapping lesions, extended lobe or bilobectomy and pneumonectomy, no chemotherapy, radiation before and after surgery, positive number of lymph nodes, and lymph node ratio (LNR) were identified as independent risk factors for higher mortality. The nomogram was created using these parameters. The C-index was 0.665 (95% confidence interval (CI), 0.651-0.679) and 0.722 (95% CI, 0.620-0.824) in the SEER and PUMCH cohorts, respectively. The calibration curves showed satisfactory consistency between the predicted and actual survival status in both the SEER and PUMCH cohorts. Competitive risk analysis confirmed that the variables in the nomogram, except radiation, are risk factors for prognosis.

Conclusions

“Resectable N2” should be assessed by a multidisciplinary team. The novel nomogram developed in this study may help with clinical decision-making for this patient population.

Beyond Programmed Death-Ligand 1: B7-H6 Emerges as a Potential Immunotherapy Target in SCLC

INTRODUCTION

The programmed death-ligand 1 (PD-L1) immune checkpoint inhibitors, atezolizumab and durvalumab, have received regulatory approval for the first-line treatment of patients with extensive-stage SCLC. Nevertheless, when used in combination with platinum-based chemotherapy, these PD-L1 inhibitors only improve overall survival by 2 to 3 months. This may be due to the observation that less than 20% of SCLC tumors express PD-L1 at greater than 1%. Evaluating the composition and abundance of checkpoint molecules in SCLC may identify molecules beyond PD-L1 that are amenable to therapeutic targeting.

METHODS

We analyzed RNA-sequencing data from SCLC cell lines (n = 108) and primary tumor specimens (n = 81) for expression of 39 functionally validated inhibitory checkpoint ligands. Furthermore, we generated tissue microarrays containing SCLC cell lines and patient with SCLC specimens to confirm expression of these molecules by immunohistochemistry. We annotated patient outcomes data, including treatment response and overall survival.

RESULTS

The checkpoint protein B7-H6 (NCR3LG1) exhibited increased protein expression relative to PD-L1 in cell lines and tumors (p < 0.05). Higher B7-H6 protein expression correlated with longer progression-free survival (p = 0.0368) and increased total immune infiltrates (CD45+) in patients. Furthermore, increased B7-H6 gene expression in SCLC tumors correlated with a decreased activated natural killer cell gene signature, suggesting a complex interplay between B7-H6 expression and immune signature in SCLC.

CONCLUSIONS

We investigated 39 inhibitory checkpoint molecules in SCLC and found that B7-H6 is highly expressed and associated with progression-free survival. In addition, 26 of 39 immune checkpoint proteins in SCLC tumors were more abundantly expressed than PD-L1, indicating an urgent need to investigate additional checkpoint targets for therapy in addition to PD-L1.