Primary Small Cell Lung Cancer Research Articles

Blocking the angiopoietin-2-dependent integrin β-1 signaling axis abrogates small cell lung cancer invasion and metastasis.

Small cell lung cancer (SCLC) is the most aggressive lung cancer entity with an extremely limited therapeutic outcome. Most patients are diagnosed at an extensive stage. However, the molecular mechanisms driving SCLC invasion and metastasis remain largely elusive. We used an autochthonous SCLC mouse model and matched samples from patients with primary and metastatic SCLC to investigate the molecular characteristics of tumor metastasis. We demonstrate that tumor cell invasion and liver metastasis in SCLC are triggered by an Angiopoietin-2 (ANG-2)/Integrin β-1-dependent pathway in tumor cells, mediated by focal adhesion kinase/Src kinase signaling. Strikingly, CRISPR-Cas9 KO of Integrin β-1 or blocking Integrin β-1 signaling by an anti-ANG-2 treatment abrogates liver metastasis formation in vivo. Interestingly, analysis of a unique collection of matched samples from patients with primary and metastatic SCLC confirmed a strong increase of Integrin β-1 in liver metastasis in comparison with the primary tumor. We further show that ANG-2 blockade combined with PD-1-targeted by anti-PD-1 treatment displays synergistic treatment effects in SCLC. Together, our data demonstrate a fundamental role of ANG-2/Integrin β-1 signaling in SCLC cells for tumor cell invasion and liver metastasis and provide a potentially new effective treatment strategy for patients with SCLC.

Synchronous double primary small cell lung cancer and invasive ductal breast carcinoma: a case report

BackgroundAlthough lung and breast cancers are common malignancies, the occurrence of primary synchronous neoplasms involving these organs has been rarely reported in literature.Case presentationA 75-year-old female patient presented at a local hospital with a ten-day history of dizziness and slurred speech. A CT contrast-enhanced scan revealed a 4.2 cm mass in the lower lobe of the right lung and a 3.8 cm space-occupying lesion in the right breast. Subsequent breast ultrasound identified a hypoechoic lesion measuring5.41 × 4.75 × 3.06 cm in the right breast, and an ultrasound-guided biopsy confirmed the presence of infiltrating ductal carcinoma of the right breast. The immunohistochemistry analysis of the breast mass revealed positive staining for ER, PR, HER-2, AR and Ki67 in the tumor cells, while negative staining was observed for P63, Calponin, CK5/6 and CK14. MR imaging of the head detected abnormal signals in the right frontal lobe (3.6 cm×2.9 cm in size), left cerebellar hemisphere, and punctate enhancement in the left temporal lobe, indicating potential metastasis. Pathological examination of a lung biopsy specimen confirmed the presence of small cell lung cancer (SCLC). Furthermore, immunohistochemistry analysis of the lung lesions demonstrated positive staining for TTF-1, CK-Pan, Syn, CgA, CD56, P53 (90%) and Ki67 (70%), and negative staining for NapsinA and P40 in the tumor cells. The patient’s diagnosis of SCLC with stage cT2bN0M1c IVB and brain metastases (BM), as well as invasive ductal breast carcinoma (IDC), was confirmed based on the aforementioned results. Whereupon we proposed a treatment plan consisting of whole-brain radiation (40 Gy/20fractions), focal radiotherapy (60 Gy/20fractions), and adjuvant concurrent chemotherapy with oral etoposide (50 mg on days 1 to 20).ConclusionsTo the best of our knowledge, the present case is the first of its kind to describe the synchronous double cancer, consisting of primary SCLC and IDC.

GPNMB Expression Associates with Inferior Prognosis in Patients with Small Cell Lung Cancer.

Purpose: Small cell lung cancer (SCLC) is widely recognized for its propensity for early and frequent metastases, which contribute to its status as a refractory malignancy. While the high expression of GPNMB in SCLC is well-documented, the precise correlation between GPNMB expression and the prognosis of SCLC remains undetermined. Methods: HTG Edge-seq was used to screen the differential gene expression between primary SCLC lesions and paired metastatic lymph nodes (LN). The plasma concentration of GPNMB was measured using enzyme-linked immunosorbent assay (ELISA). The relationship between GPNMB concentration and clinical characteristics, as well as overall survival (OS) was assessed. One-to-one propensity score matching (PSM) was performed to reduce bias from confounding factors between groups. The invasive, migratory, proliferative, and apoptotic abilities of SCLC cells were evaluated using migration and matrigel invasion assays, CCK8 assay and flow cytometry respectively. Results: GPNMB exhibited a significant up-regulation in LN compared to primary SCLC lesions as determined by HTG Edge-seq. Furthermore, patients with extensive disease demonstrated a significantly elevated plasma GPNMB concentration compared to those with local disease (P = 0.043). Additionally, patients with a high baseline plasma GPNMB level exhibited a shorter OS (10.32 vs. 16.10 months, P = 0.0299). Following PSM analysis, the statistical significance of the difference between the two groups persisted (9.43 vs. 15.27 months, P = 0.0146). Notably, both univariate and multivariate analyses confirmed that higher expression of GPNMB served as an independent biomarker for OS before PSM (P = 0.033, HR = 2.304) and after PSM (P = 0.003, HR = 6.190). Additionally, our study revealed that the inhibition of GPNMB expression through the use of siRNA effectively diminished the metastatic and proliferative capabilities of SCLC. Furthermore, this inhibition resulted in an enhanced ability to induce apoptosis. Conclusions: In light of our findings, it can be inferred that the expression of GPNMB is linked to metastasis and an unfavorable prognosis, thus suggesting its potential as a novel therapeutic target in the treatment of SCLC.

Deep Learning Based on Enhanced MRI T1 Imaging to Differentiate Small-cell and Non-small-cell Primary Lung Cancers in Patients with Brain Metastases.

To differentiate the primary small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC) for patients with brain metastases (BMs) based on a deep learning (DL) model using contrast-enhanced magnetic resonance imaging (MRI) T1 weighted (T1CE) images. Out of 711 patients with BMs of lung cancer origin (SCLC 232, NSCLC 479), the MRI datasets of 192 patients (lesions' widths and heights > 30 pixels) with BMs from lung cancer (73 SCLC and 119 NSCLC) confirmed pathologically were enrolled, retrospectively. A typical convolutional neural network ResNet18 was applied for the automatic classification of BMs lesions from lung cancer based on T1CE images, with training and testing groups randomized per patient to eliminate learning bias. A 5-fold cross-validation was performed to evaluate the classification of the model. The receiver operating characteristic (ROC) curve, accuracy, precision, recall and f1 score were calculated. For a 5-fold cross-validation test, the DL model achieved AUCs of 0.8019 and 0.8024 for SCLC and NSCLC patients with BMs, respectively, and a mean overall accuracy of 0.7515±0.04. The DL model performed well in differentiating the primary SCLC and NSCLC with BMs. The proposed DL model is feasible and effective in differentiating the pathological subtypes of SCLC and NSCLC causing BMs, which may be used as a new tool for oncologists to diagnose noninvasively BMs and guide therapy based on the imaging structure of tumors.

Whole Liver Radiotherapy for Multiple Liver Metastases in Thoracic Malignancies

Liver metastases (LM) are common in advanced thoracic cancer patients with dismal oncological outcomes. Even in the modern era of novel systemic therapy, LM led to a 21% increased mortality risk compared with those without. Options for progressive multiple LM after systemic therapy are limited. Therefore, a different treatment modality is urgently needed to overcome such a predicament. Herein, we renovate the classical whole liver radiotherapy (WLRT) and evaluate its efficacy and safety in treating thoracic cancer patients with progressive multiple LM. Patients with lung or thymic cancer who had multiple LM treated by WLRT between 2018 and 2022 were enrolled. Radiotherapy (RT) was delivered with a median dose of 24 Gy (range 8-25 Gy) in 8 fractions (range 1-16) at the discretion of treating physicians. Overall survival (OS) and cumulative incidence of intrahepatic progression were calculated from the completion of WLRT till death or progression by Kaplan-Meier and competing risk analyses, respectively. Twenty-four patients were enrolled in this retrospective study. Eleven patients (46%) had lung adenocarcinoma, of which nine patients had oncogenic mutations. Six patients (25%) had small cell lung cancer (SCLC), four patients (17%) had thymic squamous cell carcinoma (SqCC), two patients (8%) had lung SqCC, and one patient (4%) had mixed histology. Eighteen patients (75%) were under systemic therapy treatment before the diagnosis of LM, and fifteen (63%) received LM biopsy. The median time from the diagnosis of LM to WLRT was 7.5 months (range, 0.5-33.9 months). Eleven patients (46%) had concurrent RT and systemic therapy. With a median follow-up of 3.1 months, the 3-, 6- and 12-month OS were 57%, 38%, and 15%, respectively. After adjusting death as a competing risk, the cumulative incidence of LM progression at 3, 6, and 12 months were 10%, 19%, and 44%, respectively. Within three months after the completion of RT, one patient (4%) had grade 5 radiation-induced liver disease (RILD), one patient (4%) had grade 4 abnormal liver function test (LFT), three patients (13%) had grade 3 abnormal LFT, and twelve patients (50%) had ≤ grade 2 abnormal LFT. The patient who had Gr.5 RILD expired 51 days after the completion of RT with 24 Gy in 8 fractions concurrently with topotecan. He had primary SCLC with viral hepatitis B. His LFT was around the normal upper limit before WLRT. WLRT provided favorable intrahepatic control with acceptable radiation-related toxicities and could be considered a treatment option for patients with progressive LM under systemic therapy. Further investigation with a larger cohort is warranted to identify patients at a high risk of developing severe RILD.

The characteristics and survival of second primary lung cancer after Hodgkin's lymphoma: A comparison with first primary lung cancer using the SEER database.

The study aimed to compare the characteristics and prognosis between patients with second primary lung cancer following Hodgkin's lymphoma and those with primary lung cancer. Using the SEER 18 database, the characteristics and prognosis were compared between the second primary non-small cell lung cancer following Hodgkin's lymphoma (HL-NSCLC) (n = 466) and the first primary non-small cell lung cancer (n = 469,851)(NSCLC-1), as well as between the second primary small cell lung cancer following Hodgkin's lymphoma (n = 93) (HL-SCLC) and the first primary small cell lung cancer (n = 94,168) (SCLC-1). Comparisons of categorical variables were performed using Chi-square or Fisher's test. Continuous variables were compared using the Mann-Whitney U test. Overall survival (OS) was estimated using the Kaplan-Meier method, and the difference between groups was analyzed by log-rank test. HL-NSCLC group had more males than NSCLC-1 group, and the median age of HL-NSCLC group was younger than that of NSCLC-1 group. Patients with HL-NSCLC showed inferior OS than those with NSCLC-1 (median: 10 months vs. 11 months, P = 0.006). Both HL-SCLC and SCLC-1 groups had poor prognosis, with median OS of 7 months (P = 0.4). The 3-year cumulative risks of death from any cause for patients with the latencies from HL to NSCLC of 0 to 5 years, >5 to 10 years, >10 to 15 years, >15 to 20 years, and>20 years were 71.8%, 82.6%, 86.8%, 85.7% and 78.5%, respectively(P = 0.020). HL-NSCLC patients had worse prognosis than NSCLC-1 patients, while HL-SCLC patients shared similar characteristics and survival with SCLC-1 patients.

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

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. 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. 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. 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.

Molecular features and evolutionary trajectory of ASCL1+ and NEUROD1+ SCLC cells.

Small cell lung cancer (SCLC) is the most aggressive subtype of lung cancer without recognised morphologic or genetic heterogeneity. Based on the expression of four transcription factors, ASCL1, NEUROD1, POU2F3, and YAP1, SCLCs are classified into four subtypes. However, biological functions of these different subtypes are largely uncharacterised. We studied intratumoural heterogeneity of resected human primary SCLC tissues using single-cell RNA-Seq. In addition, we undertook a series of in vitro and in vivo functional studies to reveal the distinct features of SCLC subtypes. We identify the coexistence of ASCL1+ and NEUROD1+ SCLC cells within the same human primary SCLC tissue. Compared with ASCL1+ SCLC cells, NEUROD1+ SCLC cells show reduced epithelial features and lack EPCAM expression. Thus, EPCAM can be considered as a cell surface marker to distinguish ASCL1+ SCLC cells from NEUROD1+ SCLC cells. We further demonstrate that NEUROD1+ SCLC cells exhibit higher metastatic capability than ASCL1+ SCLC cells and can be derived from ASCL1+ SCLC cells. Our studies unveil the biology and evolutionary trajectory of ASCL1+ and NEUROD1+ SCLC cells, shedding light on SCLC tumourigenesis and progression.

Transcriptional Profiling Reveals Mesenchymal Subtypes of Small Cell Lung Cancer with Activation of the Epithelial-to-Mesenchymal Transition and Worse Clinical Outcomes.

While molecular subtypes of small cell lung cancers (SCLC) based on neuroendocrine (NE) and non-NE transcriptional regulators have been established, the association between these molecular subtypes and recently recognized SCLC-inflamed (SCLC-I) tumors is less understood. In this study, we used gene expression profiles of SCLC primary tumors and cell lines to discover and characterize SCLC-M (mesenchymal) tumors distinct from SCLC-I tumors for molecular features, clinical outcomes, and cross-species developmental trajectories. SCLC-M tumors show elevated epithelial-to-mesenchymal transformation (EMT) and YAP1 activity but a low level of anticancer immune activity and worse clinical outcomes than SCLC-I tumors. The prevalence of SCLC-M tumors was 3.2-7.4% in primary SCLC cohorts, which was further confirmed by immunohistochemistry in an independent cohort. Deconvoluted gene expression of tumor epithelial cells showed that EMT and increased immune function are tumor-intrinsic characteristics of SCLC-M and SCLC-I subtypes, respectively. Cross-species analysis revealed that human primary SCLC tumors recapitulate the NE-to-non-NE progression murine model providing insight into the developmental relationships among SCLC subtypes, e.g., early NE (SCLC-A and -N)- vs. late non-NE tumors (SCLC-M and -P). Newly identified SCLC-M tumors are biologically and clinically distinct from SCLC-I tumors which should be taken into account for the diagnosis and treatment of the disease.

Outcomes of Stereotactic Radiosurgery for Brain Metastases in Patients with Small-Cell Lung Cancer

<h3>Purpose/Objective(s)</h3> Several randomized studies have established stereotactic radiosurgery (SRS) as a first-line treatment modality for limited brain metastases. However, these trials frequently excluded patients with primary small cell lung cancer (SCLC). Here, we assess clinical outcomes of patients with primary SCLC who have undergone SRS for brain metastases. <h3>Materials/Methods</h3> We identified patients with histologically-proven SCLC who underwent first-time SRS for brain metastases at our institution. Overall survival, local recurrence, and time to distant CNS failure were estimated with the Kaplan-Meier method. Univariate log-rank test and multivariate Cox regression were used to assess the significance of prognostic factors including age, sex, prior whole brain radiation, number of brain metastases, and extracranial disease control status. <h3>Results</h3> Fifty-nine patients (median age 64) with SCLC completed SRS for brain metastases at our institution from July 2007 to December 2021. 88.1% (n=52) of patients received Gamma Knife SRS, whereas the remainder received LINAC-based SRS. 61.0% (n=36) had received prior whole brain or prophylactic cranial irradiation. The median number of treated brain metastases was 2 (range 1-11) with a median tumor diameter of 1.0 cm and a marginal dose of 18 Gy. Median overall survival was 11 months. On multivariate Cox regression, both increased number of brain metastases (HR 1.22; 95% CI 1.02-1.44) and increased age (HR 1.09; 95% CI 1.03-1.16) were associated with poorer overall survival. 11.9% (n=7) of patients experienced local recurrence at a median of 5 months post-SRS (range 2-9 months). The median time to distant CNS failure was 6 months. Multivariate analysis identified extracranial disease control status as the sole significant predictor of distant failure. Log-rank test demonstrated that the patient cohort with uncontrolled extracranial disease had a lower time to distant failure compared to those with stable or well-controlled disease (4 vs. 22 months; p=0.0001). <h3>Conclusion</h3> SRS provides excellent local control of SCLC-associated brain metastases without compromising overall survival. Our institutional data support the rationale for future prospective studies to establish the role of intracranial SRS in this patient population.

The extent of mediastinal lymph node dissection correlates with survival of small cell lung cancer patients after resection: a propensity score-matched cohort study analysis.

BackgroundEvidence on the importance of lymph node (LN) dissection during resection for small cell lung cancer (SCLC) is scarce. This study sought to investigate the clinical impact of the extent of lymphadenectomy on the survival of patients with SCLC.MethodsPatients who underwent resection for primary SCLC between 2000 and 2016 were identified from the Surveillance, Epidemiology, and End Results (SEER) cancer registry. The patients were stratified based on the number of LNs dissected (0, 1–3, 4–11, and ≥12) via an X-Tile software analysis, and lung cancer-specific survival (LCSS) and overall survival (OS) were compared between these stratified groups using Kaplan-Meier curves. A propensity score-matched analysis and a Cox regression model were used to adjust for potential confounders.ResultsA total of 1,883 patients with SCLC met our criteria and were enrolled in the study. The LCSS and OS analyses revealed that patients who underwent LN dissection during surgery had longer survival times significantly than patients who did not. Similarly, patients who underwent more extensive LN dissection (≥4 LNs) had longer survival times than those who underwent less extensive LN dissection (1–3 LNs). However, no significant increase in survival time was found for patients who underwent the dissection of ≥12 LNs compared to those who underwent the dissection of 4–11 LNs. These results were confirmed in our propensity-matched and Cox regression analyses.ConclusionsOur study revealed that patient survival after surgical resection for SCLC is associated with the number of dissected LNs, and the number of LNs for dissection ranges from 4 to 11 achieve the best survival outcome.

ABBV-011, A Novel, Calicheamicin-Based Antibody-Drug Conjugate, Targets SEZ6 to Eradicate Small Cell Lung Cancer Tumors.

In the past year, four antibody-drug conjugates (ADC) were approved, nearly doubling the marketed ADCs in oncology. Among other attributes, successful ADCs optimize targeting antibody, conjugation chemistry, and payload mechanism of action. Here, we describe the development of ABBV-011, a novel SEZ6-targeted, calicheamicin-based ADC for the treatment of small cell lung cancer (SCLC). We engineered a calicheamicin conjugate that lacks the acid-labile hydrazine linker that leads to systemic release of a toxic catabolite. We then screened a patient-derived xenograft library to identify SCLC as a tumor type with enhanced sensitivity to calicheamicin ADCs. Using RNA sequencing (RNA-seq) data from primary and xenograft SCLC samples, we identified seizure-related homolog 6 (SEZ6) as a surface-expressed SCLC target with broad expression in SCLC and minimal normal tissue expression by both RNA-seq and IHC. We developed an antibody targeting SEZ6 that is rapidly internalized upon receptor binding and, when conjugated to the calicheamicin linker drug, drives potent tumor regression in vitro and in vivo. These preclinical data suggest that ABBV-011 may provide a novel treatment for patients with SCLC and a rationale for ongoing phase I studies (NCT03639194).

Transcriptional analysis of small cell lung cancer transformation in epidermal growth factor receptor mutated lung adenocarcinomas.

e21100 Background: Epidermal growth factor receptor ( EGFR)-mutated lung adenocarcinoma (LUAD) could benefit from EGFR-TKIs (tyrosine kinase inhibitors) treatment, but drug resistance seems to be inevitable. Small cell lung cancer (SCLC) transformation counts for 3-15% of the resistance mechanism, and was amply studied at genomics level but rarely at transcriptional level. Methods: The expression of 730 mRNAs were investigated by Nanostring nCounter Pancancer Pathway Panel on 72 formalin-fixed and paraffin-embedded (FFPE) samples from 27 EGFR-mutated LUAD patients with SCLC transformation after EGFR-TKIs therapy (19 LUAD samples before transformation, LUAD-BT; 21 SCLC samples after transformation, SCLC-AT), 12 EGFR-mutated LUAD patients never SCLC transformed after EGFR-TKIs therapy (12 samples, LUAD-NT) and 20 stage IIĨIV primary SCLC patients (20 samples, SCLC-P). For patients enrolled in LUAD-NT group, tissue biopsies were performed at least twice, which were all diagnosed as pure LUAD, and the overall survival (OS) since first line therapy was longer than the median transformation time (mTt) of SCLC-transformed patients in our study. mRNA expression patterns and biological pathway scores were compared among four groups. The candidate predictive biomarkers from mRNA expression pattern analysis were validated by area under curve (AUC) of receiver operating characteristic curve (ROC) and the logarithm of fold change to the base 2 (log2FC). Results: On the last day of follow up (1st February 2022), the shortest OS of LUAD-NT patients was 28.4 months, whereas the mTt was 27.5 months. Among four groups, LUAD-NT and LUAD-BT showed the most similar mRNA expression patterns, and SCLC-P were significantly different from the others. 8.6% (63/730) mRNA showed significant downregulation after SCLC transformation, while 3.6% (26/730) showed significant upregulation ( p value adjusted by Benjamin &amp; Hochberg’s method &lt; 0.05, SCLC-AT vs LUAD-BT). In pathway enrichment analysis, the score of RAS and TGF-β pathways were significantly lower in SCLC-AT than LUAD-BT. Compared with SCLC-P, 6 upregulated mRNAs in SCLC-AT were observed (log2FC &gt; 2, AUC &gt; 0.85 and each raw p value &lt; 0.05), including AR, COL5A1, GHR, HMGA2, IGFBP3 and IL6R, which could be further validated as diagnostic markers in a larger cohort. Moreover, compared with LUAD-NT, 4 mRNAs ( BRIP1, CCNE2, CDKN2A and MCM2) were found to be significantly upregulated (log2FC &gt; 1, AUC &gt; 0.75 and each raw p value &lt; 0.05) in LUAD-BT, indicating the predictive value of SCLC transformation. Conclusions: The transformation of LUAD to SCLC may be promoted by transcriptional events. We also described some significantly different expressed mRNAs that could candidate as predictive or diagnostic markers for SCLC transformation, which should be further validated in a larger cohort.

CD133 as a Biomarker for an Autoantibody-to-ImmunoPET Paradigm for the Early Detection of Small Cell Lung Cancer.

Small cell lung cancer (SCLC) is a deadly neuroendocrine tumor for which there are no screening methods sensitive enough to facilitate early, effective intervention. We propose targeting the neuroendocrine tumor neoantigen CD133 via antibody-based early detection and PET (immunoPET) to facilitate earlier and more accurate detection of SCLC. Methods: RNA sequencing datasets, immunohistochemistry, flow cytometry, and Western blots were used to quantify CD133 expression in healthy and SCLC patients. CD133 was imaged invivo using near-infrared fluorescence (NIRF) immunoimaging, and 89Zr immunoPET. Anti(α)-CD133 autoantibody levels were measured in SCLC patient plasma using antibody microarrays. Results: Across 6 publicly available datasets, CD133 messenger RNA was found to be higher in SCLC tumors than in other tissues, including healthy or normal adjacent lung and non-SCLC samples. Critically, the upregulation of CD133 messenger RNA in SCLC was associated with a significant increase (hazard ratio, 2.62) in death. CD133 protein was expressed in primary human SCLC, in SCLC patient-derived xenografts, and in both SCLC cell lines tested (H82 and H69). Using an H82 xenograft mouse model, we first imaged CD133 expression with NIRF. Both invivo and ex vivo NIRF clearly showed that a fluorophore-tagged αCD133 homed to lung tumors. Next, we validated the noninvasive visualization of subcutaneous and orthotopic H82 xenografts via immunoPET. An αCD133 antibody labeled with the positron-emitting radiometal 89Zr demonstrated significant accumulation in tumor tissue while producing minimal uptake in healthy organs. Finally, plasma αCD133 autoantibodies were found in subjects from cohort studies up to 1 year before SCLC diagnosis. Conclusion: In light of these findings, we conclude that the presence of αCD133 autoantibodies in a blood sample followed by CD133-targeted 89Zr-immunoPET could be an effective early detection screening strategy for SCLC.

Enhanced AC133-specific CAR T cell therapy induces durable remissions in mice with metastatic small cell lung cancer

Metastatic small cell lung cancer (SCLC) is not curable. While SCLC is initially sensitive to chemotherapy, remissions are short-lived. The relapse is induced by chemotherapy-selected tumor stem cells, which express the AC133 epitope of the CD133 stem cell marker. We studied the effectiveness of AC133-specific CAR T cells post-chemotherapy using human primary SCLC and an orthotopic xenograft mouse model. AC133-specific CAR T cells migrated to SCLC tumor lesions, reduced the tumor burden, and prolonged survival in a humanized orthotopic SCLC model, but were not able to entirely eliminate tumors. We identified CD73 and PD-L1 as immune-escape mechanisms and combined PD-1-inhibition and CD73-inhibition with CAR T cell treatment. This triple-immunotherapy induced cures in 25% of the mice, without signs of graft-versus-host disease or bone marrow failure. AC133+ cancer stem cells and PD-L1+CD73+ myeloid cells were detectable in primary human SCLC tissues, suggesting that patients may benefit from the triple-immunotherapy. We conclude that the combination of AC133-specific CAR T cells, anti-PD-1-antibody and CD73-inhibitor specifically eliminates chemo-resistant tumor stem cells, overcomes SCLC-mediated T cell inhibition, and might induce long-term complete remission in an otherwise incurable disease.

Development and Validation of a Nomogram for Predicting Overall Survival in Patients with Second Primary Small Cell Lung Cancer After Non-Small Cell Lung Cancer: A SEER-Based Study

BackgroundNon-small cell lung cancer (NSCLC) survivors are at an increased risk of developing second primary malignancies, such as small cell lung cancer. This paper sought to establish a prognostic nomogram to assess overall survival (OS) in patients with second primary small cell lung cancer (SPSCLC) after NSCLC.Methods420 patients who developed SPSCLC after NSCLC were randomly split into the training and validation groups. A nomogram was established by stepwise regression. Area under the curve (AUC) and calibration plots were applied to assess the prognostic performance of the nomogram. Concordance index (C-index), integrated discrimination improvement (IDI), net reclassification index (NRI) and decision curve analysis (DCA) were performed to compare the nomogram with the American Joint Committee on Cancer (AJCC) 8th staging system. Survival risk classification was constructed based on the nomogram.ResultsFive variables were chosen to construct the nomogram. The AUC showed that it had a satisfactory discrimination ability. All calibration plots displayed good concordance between nomogram and observation. The C-index, IDI, NRI and DCA showed the nomogram was superior to the AJCC 8th staging system. The Kaplan-Meier curves suggested huge differences in prognosis among the three risk groups.ConclusionThis study build a nomogram and risk stratification system for predicting probabilities of OS in patients with SPSCLC after NSCLC, which can help clinicians in individualized survival assessment and treatment decisions.

Molecular Subtypes of High-Grade Neuroendocrine Carcinoma (HGNEC): What is YAP1-Positive HGNEC?

Small cell lung cancer (SCLC) subtype classification, based on high-level expression of key transcriptional regulators; ASCL1 (SCLC-A), NEUROD1 (SCLC-N), POU2F3 (SCLC-P), and YAP1 (SCLC-Y), has recently been proposed. YAP1 (and POU2F3) has attracted attention as an important factor for non-neuroendocrine (non-NE) phenotypic subtyping of SCLC. However, subsequent studies reported that YAP1 expression alone cannot define a single group in primary SCLC, which makes it difficult to understand what SCLC-Y is by focusing only on SCLC. In this review, we concluded that YAP1 is an essential anti-neuroendocrine factor in both SCLC and non-small cell lung cancer (NSCLC) based on previous studies, including our own analysis of the cell lines and primary tumors of SCLC and NSCLC. The classification of SCLC-Y is a concept mainly established from the analysis of cell lines, and SCLC-Y cell lines correspond to "variant type" SCLC cell lines. Primary SCLC and large cell neuroendocrine carcinoma (LCNEC) are typically heterogeneous tumors composed mostly of NE-type cells, but they contain a small number of non-NE-type cells. Importantly, individual cells with NE features exhibit YAP1 loss, whereas the non-NE-type cells exhibit YAP1 expression. Although rare in primary SCLC, some cases of primary LCNEC have many YAP1-positive cells, which is correlated with chemotherapy resistance. YAP1 staining may be useful in the exclusion diagnosis of SCLC or in the selection of treatment for LCNEC.

Prognostic Implications of Molecular Subtypes in Primary Small Cell Lung Cancer and Their Correlation With Cancer Immunity.

IntroductionSmall cell lung cancer (SCLC) has recently been characterized as heterogeneous tumors due to consensus nomenclature for distinct molecular subtypes on the basis of differential expression of four transcription markers (ASCL1, NEUROD1, POU2F3, and YAP1). It is necessary to validate molecular subtype classification in primary SCLC tumors by immunohistochemical (IHC) staining and investigate its relevance to survival outcomes.MethodsUsing a large number of surgically resected primary SCLC tumors, we assessed the mRNA and protein levels of the four subtype markers (ASCL1, NEUROD1, POU2F3 and YAP1) in two independent cohorts, respectively. Next, molecular subtypes defined by the four subtype markers was conducted to identify the association with clinicopathologic characteristics, survival outcomes, the expression of classic neuroendocrine markers, and molecules related to tumor immune microenvironment.ResultsSamples were categorized into four subtypes based on the relative expression levels of the four subtype markers, yielding to ASCL1, NEUROD1, POU2F3 and YAP1 subtypes, respectively. The combined neuroendocrine differentiation features were more prevalent in either ASCL1 or NEUROD1 subtypes. Kaplan-Meier analyses found that patients with tumors of the YAP1 subtype and ASCL1 subtype obtained the best and worst prognosis on both mRNA and IHC levels, respectively. Based on multivariate Cox proportional-hazards regression model, molecular subtype classification determined by IHC was identified as an independent indicator for survival outcomes in primary SCLC tumors. Correlation analyses indicated that the four subtype markers in SCLC cancer cells were interacted with its tumor immune microenvironment. Specifically, tumors positive for YAP1 was associated with fewer CTLA4+ T cell infiltration, while more immune-inhibitory receptors (FoxP3,PD1, and CTLA4) and fewer immune-promoting receptor (CD8) were found in tumors positive for ASCL1.ConclusionsWe validated the new molecular subtype classification and clinical relevance on both mRNA and protein levels from primary SCLC tumors. The molecular subtypes determined by IHC could be a pre-selected effective biomarker significantly influenced on prognosis in patients with SCLC, which warrants further studies to provide better preventative and therapeutic options for distinct molecular subtypes.

Research Advances on Transformation to Small Cell Lung Cancer

小细胞肺癌（small cell lung cancer, SCLC）转化是非小细胞肺癌尤其是表皮生长因子受体（epidermal growth factor receptor, EGFR）突变患者的重要耐药机制之一。目前发现转化性SCLC具有与原发性SCLC相似的临床特征，对化疗短期有效，中位生存期仅1年左右。RB1缺失、体细胞拷贝数改变与SCLC转化有关，但发生SCLC转化的确切分子机制仍不完全清楚。转化性SCLC的治疗也面临巨大的挑战，针对SCLC的化疗方案是目前的主要治疗选择，联合治疗、局部治疗以及预防SCLC转化的策略也在探索。本文将转化性SCLC的临床特征、分子机制和治疗选择进行综述。

A Comparative Analysis of the Gene Expression Profiles of Small Cell Esophageal Carcinoma, Small Cell Lung Cancer, and Esophageal Adeno/Squamous Carcinoma

Purpose/objectives: Primary small cell esophageal carcinoma (SCEC) is a rare malignancy without an established treatment strategy. This study investigated the gene expression profile of SCEC and compared it with the expression profiles of small cell lung cancer (SCLC) and esophageal adeno/squamous carcinoma (EAC/ESCC).Materials/methods: All patients with SCEC, SCLC, and EAC/ESCC in the Surveillance, Epidemiology, and End Results (SEER) database 1973–2014 were included. Overall survival (OS) and prognostic analysis were conducted. De novo expression array analysis was performed on three pairs of frozen primary SCEC tissues and the corresponding normal samples from the institutional tissue bank using the Affymetrix HG U133 plus 2.0 Array. These data were complemented with public domain expression data sets from the Gene Expression Omnibus (GEO) repository using the same working platforms, which included primary SCLC, EAC/ESCC, and normal lung/esophagus specimens (series GSE30219 and GSE26886). After individual normalization, the primary tumors were submitted to statistical analysis (GeneSpring GX 13.0) to identify the differentially expressed genes (DEGs) relative to their paired normal tissues. Enrichments of genes categorized by function and gene interactions were analyzed by DAVID 6.8 and STRING 11.0, respectively.Results: The clinical outcomes of the patients with SCEC were significantly more worse than those with EAC/ESCC and SCLC in the SEER database. SCEC had more DEGs in common with SCLC than EAC/ESCC [829 vs. 450; false discovery rate (FDR) < 0.01; and fold change ≥2], leading to a stronger correlation between SCEC and SCLC (Pearson's correlation coefficient was 0.60 for SCEC vs. SCLC, 0.51 or 0.45 for SCEC vs. ESCC or EAC, and the coefficient was 0.73 for ESCC vs. EAC). Similar findings were obtained by principal component analysis (PCA) using all DEGs retrieved from these four groups. Functional annotation showed that a higher proportion of pathways and biological processes were common between SCEC and SCLC and were associated with the cell cycle (mitosis), DNA replication, telomere maintenance, DNA repair, and P53 and RB pathways (Benjamini p < 0.05). Compared with EAC/ESCC, SCEC shared more co-upregulated DEGs coding for the aforementioned common pathways with SCLC (584 vs. 155). In addition, SCEC and SCLC were found to have possessed overlapping gene-interactive networks, with centromere protein F (CENPF), never in mitosis gene A-related kinase 2 (NEK2), kinesin family member 11 (KIF11), thymopoietin (TMPO), and forkhead box protein M1 (FOXM1) as common skeletons centered by gene regulatory network (NUF2).Conclusions: This study is the first attempt to examine the genomic signatures of SCEC at the transcriptomic level and compare the expression profiles between SCEC, SCLC, and EAC/ESCC. Our preliminary data indicate that SCEC and SCLC display notably similar patterns of gene expression for mitosis and DNA repair. Further validation studies are warranted.