Small Cell Lung Cancer Research Articles

Management of Stage III Non–Small Cell Lung Cancer: ASCO Guideline Rapid Recommendation Update Clinical Insights

Management of Stage III Non–Small Cell Lung Cancer: ASCO Guideline Rapid Recommendation Update Clinical Insights

A novel mouse model recapitulating the MMR-defective SCLC subtype uncovers an actionable sensitivity to immune checkpoint blockade.

Small cell lung cancer (SCLC) has an extremely poor prognosis. Despite high initial response rates to chemotherapy and modest survival improvements with the addition of immune checkpoint inhibitors (ICI), almost all patients experience relapse and fatal outcomes. Recent genomic insights uncovered extensive molecular heterogeneity in addition to the almost uniform loss of RB1 and TRP53. Additionally, defective DNA mismatch repair (MMR) has recently been described in some SCLC cases. Here, we generated a novel SCLC mouse model capturing MMR deficiency and assessed immunotherapy responses. We developed an MMR-deficient genetically engineered mouse model (GEMM) of SCLC by introducing a conditional Msh2 gene, crucial for maintaining MMR integrity, into the standard Rb1fl/fl;Trp53fl/fl (RP) model. Genomic characteristics and preclinical therapy responses were evaluated by focusing on overall survival and whole exome sequencing (WES) analyses. MMR-defective SCLC tumors (Rb1fl/fl;Trp53fl/fl;Msh2fl/fl (RPM)) developed later than tumors in MMR-proficient mice. However, the time from tumor manifestation to death of the affected animals was substantially shortened (median survival 55 days in RP vs. 46.5 days in RPM), indicating increased aggressiveness of MMR-defective tumors. RPM tumors exhibited MMR deficiency, high tumor mutational burden (TMB), and an elevated load of candidate neoantigens, compared to RP lesions (p = 0.0106), suggesting increased immunogenicity. Importantly, the overall survival of RPM animals was significantly improved when exposed to ICI. We propose a novel RPM mouse model as a suitable system to mimic MMR-defective SCLC and tumors with high TMB. We provide in vivo evidence that Msh2 deficiency enhances ICI sensitivity. These findings could contribute to stratifying SCLC patients to immunotherapy, thereby improving treatment outcomes.

Overview of Systematic Reviews of ICIs in NSCLC With EGFR, ALK, ROS1, and RET Actionable Driver Mutations

The effectiveness and safety of immune checkpoint inhibitor (ICI) monotherapy in patients with previously treated advanced or metastatic non–small cell lung cancer with EGFR, ALK, ROS1, or RET actionable driver mutations or chromosomal rearrangements is currently uncertain. We assessed the efficacy and safety of ICIs in patients with this condition whose disease did not respond well to previous chemotherapy. We reviewed 13 systematic reviews of randomized controlled trials (RCTs). The quality assessment of these reviews revealed critical methodological flaws. All 13 systematic reviews focused on survival and progression-free survival (PFS) for patients with non–small cell lung cancer and EGFR gene mutations. The systematic reviews generally considered the same set of 4 clinical trials and did not report on other outcomes or patient groups, except for 1 review that looked at patients with different levels of anti-PD-L1 expression. We found no evidence on the efficacy and safety of ICIs in patients with ALK, ROS1, or RET mutations. Overall, the systematic reviews concluded that using ICIs alone, as a second-line therapy or beyond, does not significantly improve overall survival (OS) and PFS compared to chemotherapy in patients with non–small cell lung cancer with EGFR gene mutations. No conclusions can be made regarding the benefits of ICIs in patients with EGFR mutations based on histology or high antiprogrammed death-ligand 1 antibody expression levels. The safety of ICIs in patients with EGFR, ALK, ROS1, or RET actionable driver mutations could not be assessed because of the lack of evidence provided in the included systematic reviews.

A review on the effects of current chemotherapy drugs and natural agents in treating non–small cell lung cancer

A review on the effects of current chemotherapy drugs and natural agents in treating non–small cell lung cancer

The impact of Prophylactic cranial irradiation on the prognosis of patients with limited-stage small cell lung cancer in the MRI era.

To evaluate the impact of prophylactic cranial irradiation (PCI) on the prognosis of patients with limited-stage small cell lung cancer (SCLC) in the era of MRI surveillance. Limited-stage SCLC patients with complete remission (CR) or partial remission (PR) of tumor after definitive chemo-radiotherapy (CRT) were retrospectively analyzed. Survival data were calculated by Kaplan-Meier methods, Cox proportional hazards model was applied for multivariate prognostic analysis. Between June 2002 and January 2017, 620 patients with limited-stage SCLC were accrued in our study. After CRT, 228 (36.8%) patients achieved CR, of whom, 29 patients did not receive PCI, among the rest 199 patients, 172 (86.4%) received brain MRI to exclude brain metastasis (BM) before PCI. With a median follow-up time of 25.6 months, the cumulative BM rate was 17.1% and 37.9% in patients who received or did not receive PCI (P = 0.011). The median survival time was 30.2 months and 30.5 months, respectively and the 1 -, 3 -, 5-year survival rates were 93.7%, 42.9%, 35.8% and 83.4%, 46.5%, 41.9%, respectively (P = 0.98). Multivariate analysis indicated that baseline KPS ≥ 90 was a favorable independent prognostic factor for OS in CR patients (HR: 0.33, 95% CI: 0.23-0.46, P = 0.000). After CRT, 392 (63.2%) patients achieved PR, 53 cases did not receive PCI and 310 (91.4%) of the remaining 339 patients received brain MRI before PCI. With a median follow-up time of 15.5 months, the cumulative brain metastasis rate was 12.7% and 46.2% respectively (P = 0.000). The median survival time was 25.7 months and 18.6 months, respectively. The 1 -, 3 -, and 5-year survival rates were 87.6%, 40.2%, 29.2% and 75.7%, 16.7%, 10.3% (P = 0.000). Baseline KPS ≥ 90 (HR: 0.32, 95% CI: 0.25-0.41, P = 0.000) and PCI (HR: 0.57, 95% CI: 0.41-0.79, P = 0.001) were favorable prognostic factors for OS in PR patients. In this study, PCI significantly reduced the incidence of BM in patients with limited-stage SCLC who were evaluated as CR and PR after CRT, but it has no significantly positive impact on overall survival in CR patients. Further prospective randomized studies were warranted.

Toripalimab Plus Chemotherapy as a First-Line Therapy for Extensive-Stage Small Cell Lung Cancer: The Phase 3 EXTENTORCH Randomized Clinical Trial.

Patients with extensive-stage small cell lung cancer (ES-SCLC) have poor prognoses and unmet medical needs. To evaluate the efficacy and safety of toripalimab plus etoposide and platinum-based chemotherapy (EP) vs placebo plus EP as a first-line treatment for patients with ES-SCLC. This multicenter, double-blind, placebo-controlled phase 3 randomized clinical trial (EXTENTORCH study) enrolled patients from September 26, 2019, to May 20, 2021, and was conducted at 49 sites in China. Eligible patients had histologically or cytologically confirmed ES-SCLC without previous systemic antitumor therapy for ES-SCLC. Data were analyzed between May 6, 2023, and June 1, 2024. Patients were randomized (1:1) to receive toripalimab, 240 mg, or placebo plus EP every 3 weeks for up to 4 to 6 cycles, followed by maintenance with toripalimab or placebo until disease progression, intolerable toxic effects, or up to 2 years of treatment. The primary end points were investigator-assessed progression-free survival (PFS) and overall survival (OS). Whole-exome sequencing results identified correlative biomarkers for clinical efficacy. Among 595 screened patients, 442 eligible patients were randomized (median [range] age, 63 [30-77] years; 366 [82.8%] male); 223 patients were randomized to toripalimab plus EP, and 219 to placebo plus EP. By April 20, 2023, the median (range) survival follow-up was 13.7 (0.0-42.7) months. Compared with placebo, toripalimab improved investigator-assessed PFS (hazard ratio [HR], 0.67 [95% CI, 0.54-0.82]; P < .001), and significantly reduced the risk of death (HR, 0.80 [95% CI, 0.65-0.98]; P = .03). The median OS was 14.6 (95% CI, 12.9-16.6) months in the toripalimab group vs 13.3 (95% CI, 11.8-14.4) months in the placebo group. Whole-exome sequencing results from 300 patients identified low intratumor heterogeneity, HLA-A11+ HLA-B62- haplotype, wild-type KMT2D and COL4A4, or sequence variations in CTNNA2 or SCN4A correlated with favorable PFS and OS in the toripalimab group. No new safety signals were observed. Grade 3 or higher treatment-emergent adverse event incidence was similar between the toripalimab and placebo safety set groups (199 of 222 patients [89.6%] vs 193 of 216 patients [89.4%], respectively). In this phase 3 randomized clinical trial, adding toripalimab to first-line chemotherapy demonstrated significant improvements in PFS and OS for patients with ES-SCLC. The treatment exhibited an acceptable safety profile, supporting this combination regimen as a new treatment option for patients with ES-SCLC. ClinicalTrials.gov Identifier: NCT04012606.

Abstract PR005: Leveraging mass cytometry for phenotyping CTCs in SCLC liquid biopsies: Tracking therapy resistance at a personalized level

Abstract Liquid biopsies present a promising, minimally invasive procedure through which clinicians can assess and monitor disease status by interrogating circulating tumor cell (CTC) and immune cell phenotypes. In the case of Small-cell lung cancer (SCLC) – a type of lung cancer characterized by aggressive growth, dismal prognosis and limited treatment options - leveraging liquid biopsies and CTCs for evaluating disease status would be of great benefit, given that biopsies are scarce. Furthermore, SCLC CTC numbers are higher compared to other cancers, presenting a unique opportunity to utilize them for assessing SCLC therapy resistance and identifying new targetable markers. In this study, we leverage mass cytometry (i.e. CyTOF) to phenotype SCLC CTC phenotypes in longitudinal clinical specimens to assess therapy resistance at a personalized level. By using CyTOF - a multiplex cytometric approach that enables interrogation of 30-50 protein markers per single cell – we show that we are able to identify and analyze a significant number of CTCs and their heterogeneous expression profiles. To achieve this, we first optimized a CyTOF panel of ∼25-30 antibodies by using SCLC cell lines and blood specimens from healthy donors and SCLC patients. We show that by using this approach, we are able to identify and phenotype SCLC CTCs by using the combination of CD45 (negative expression) and CD56 positive expression with further validation achieved by TTF1 and SCLC subtype transcription factor expression (NEUROD1, POU2F3 and ASCL1). This approach avoids enriching for specific CTC epithelial phenotypes that express surface markers that fluctuate during epithelial- mesenchymal transition (EMT) (e.g. EpCAM, a common marker for isolating CTCs). For parallel immune profiling we assessed among others CD8/CD4 (T cells) and CD11b/HLA-DR (Myeloid-derived suppressor cells, MDSCs) expression. We then proceeded to interrogate CTC phenotypic differences in the naïve vs relapsed setting as well as dynamic changes in longitudinal blood specimens from SCLC patients by evaluating markers that describe immune suppression activity (PD-L1) and EMT status (E-Cadherin, Vimentin, MUC1, Twist and Slug). Importantly, we show that with our approach we can track in real time therapeutic targets that are currently being tested in clinical trials or have been recently FDA approved (e.g. pYAP and DLL3) and found that MUC1 and pYAP are significantly increased in CTCs detected in blood specimens of SCLC relapsed patients. Our immune profiling showed an increase of MDSC percentages and a decrease in the CD4/CD8 T cell ratio in the relapsed setting. Finally, when we used PHENOSTAMP, a previously developed reference EMT map for assessing EMT phenotypes in lung cancer clinical specimens, we observed an increase of EMT heterogeneity in CTCs in relapsed patients. Our study highlights the translational power of our approach in utilizing CyTOF for longitudinally tracking CTCs directly in SCLC patient liquid biopsies towards assessing therapy response and resistance at a personalized level. Citation Format: Loukia G Karacosta, Sayantan Bhattacharyya, Allison Stewart, Ashley Victorian, Ester F Lujan, Shafqat Ehsan, Subin Kim, Alberto Duarte, Runsheng Wang, Benedict Anchang, Jing Wang, Lauren Byers. Leveraging mass cytometry for phenotyping CTCs in SCLC liquid biopsies: Tracking therapy resistance at a personalized level [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr PR005.

Abstract B036: Pathway repression in progression on osimertinib therapy in NSCLC via a comprehensive genomic and epigenomic circulating tumor DNA (ctDNA) assay

Abstract Background: Osimertinib is currently the most common precision therapy for patients with non- small cell lung cancer (NSCLC) with EGFR mutations. While it prolongs progression-free survival, resistance eventually develops in many, leading to disease progression. Somatic NGS has identified resistance mutations in the EGFR pathway and other oncogenes, but these account for only 40-45% of cases, suggesting non-genetic factors, such as epigenetic changes, may be involved. This study investigates the epigenetic landscape at diagnosis and progression on first- line osimertinib, focusing on cases with and without canonical resistance mutations. Methods: We defined two cohorts from GuardantINFORM, a clinico-genomics database, restricting to only patients with a test on the Guardant Infinity platform, a comprehensive blood-based NGS assay, that analyzes DNA sequence variants and performs extensive methylation profiling (∼15Mb) in &amp;gt;20,000 differentially methylated regions (DMRs) assessed for sample-specific methylation patterns. (A) Diagnosis Cohort: Comprised of 34 NSCLC patients with blood samples collected within six days prior to the initiation of first-line osimertinib therapy. (B) Progression Cohort: Comprised of 36 patients who were on first-line osimertinib therapy, with blood samples collected within 60 days of discontinuation. The progression cohort was further stratified based on the presence or absence of known resistance mutations identified through somatic variant analysis by Guardant360. Gene set enrichment analysis was conducted on these methylation profiles using the Reactome database to define pathway-level differences between the cohorts. Results: Pathway enrichment analysis in the diagnosis and progression cohorts found expected biological processes in NSCLC such as extracellular matrix organization, G- protein coupled receptor (GPCR) signaling, and FGFR pathways. Additionally, the progression cohort lacking canonical resistance mutations (n=23) exhibited unique enrichment in two specific pathways: Glucose-dependent Insulinotropic Polypeptide and Physiological Factors. These pathways include genes such as GATA4, which has been implicated in the epithelial- mesenchymal transition (EMT)—a process associated with transforming to a small cell phenotype, a known mechanism of resistance to EGFR inhibition, including osimertinib. Conclusion: This study demonstrates the utility of epigenetic profiling via liquid biopsies in uncovering non-genetic mechanisms underlying osimertinib resistance in advanced NSCLC. Identification of unique epigenetic pathways in progressing patients without canonical resistance mutations highlights the potential for discovering novel biomarkers of resistance. Further investigation into these findings may advance our understanding of resistance mechanisms across various cancer therapies, particularly for patients without identified genomic resistance, and inform clinical decision-making and trial design. Citation Format: Aaron Hardin, Leslie Bucheit, Amar Das, Craig Eagel, Helmy Eltoukhy. Pathway repression in progression on osimertinib therapy in NSCLC via a comprehensive genomic and epigenomic circulating tumor DNA (ctDNA) assay [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr B036.

Molecular Interactions of the Plant Steroid Hormone Epibrassinolide on Human Drug-Sensitive and Drug-Resistant Small-Cell Lung Carcinoma Cells

Background: Small-cell lung cancer (SCLC) has a poor prognosis because it is often diagnosed after it has spread and develops multi-drug resistance. Epibrassinolide (EB) is a plant steroid hormone with widespread distribution and physiological effects. In plants, EB-activated gene expression occurs via a GSK-mediated signaling pathway, similar to Wnt-β-catenin signaling in animal cells that is elevated in cancer cells. Methods: This mechanistic parallel prompted investigations of the molecular interactions of EB on drug-sensitive (H69) and multi-drug-resistant (VPA) SCLC cells. Cellular and molecular investigations were performed. Results: Pharmacologic interactions between EB and the Wnt signaling inhibitors IGC-011 and PRI-724 were determined by the combination index method and showed antagonism, indicating that EB acts on the same pathway as these inhibitors. Following incubation of drug-sensitive and drug-resistant SCLC cells with EB, there was a reduction in β-catenin (e.g., 3.8 to 0.7 pg/µg protein), accompanied by a reduction in β-catenin promoter activity, measured by firefly luciferase-coupled promoter element transfection. Cellular β-catenin concentration is regulated by the active form of GSK3β. In Wnt signaling, active GSK3β is converted to inactive pGSK3β, thereby increasing the concentration of β-catenin. After incubation of SCLC cells with EB, there was a reduction in the inactive form (pGSK3β) and a relative increase in the active form (GSK3β). In vitro enzyme assays showed that EB did not inhibit purified GSK3β, but there was non-competitive inhibition when SCLC cell extracts were used as the source of enzyme. This indirect inhibition by EB indicates that it may act on the Wnt pathway by blocking the phosphorylation of GSK3β. The protein levels of three SCLC tumor markers, namely, NSE, CAV1, and MYCL1, were elevated in drug-resistant SCLC cells. EB incubation led to a significant reduction in the levels of the three markers. Two major effects of EB on SCLC cells are the promotion of apoptosis and the reversal of drug resistance. Transcriptional analyses showed that after exposure of SCLC cells to EB, there were increases in the expression of genes encoding apoptotic inducers (e.g., BAX and FAS) and effectors (e.g., CASP3) and reductions in the expression of genes encoding apoptosis inhibitors (e.g., survivin). PGP1 and MRP1, two membrane efflux pumps expressed in SCLC cells, were elevated in drug-resistant cells, but EB incubation did not affect these protein levels. Cellular assays of drug efflux by PGP1 showed an increase in drug-resistant cells, but EB did not alter efflux activity. Following exposure to human liver microsomes, EB was metabolized by NADPH-dependent oxidation and UDPG-dependent glucuronidation, as evidenced by the elimination of EB cytotoxicity against SCLC cells. Conclusions: Taken together, these data indicate that EB, a steroid hormone in plants consumed in the human diet, is pharmacologically active in drug-sensitive and drug-resistant SCLC cells in the Wnt signaling pathway, alters apoptotic gene expression, and is a substrate for microsomal modifications.

Chemiluminescent Fe3O4@Nickel-Cobalt Double Hydroxide Magnetic Core-Shell Nanomaterial as an Analytical Interface for Label-Free CYFRA21-1 Immunosensing.

Cytokeratin 19 fragment (CYFRA21-1) is considered to be a potential marker for the diagnosis and of classification of lung cancer. It is highly desired to develop rapid and highly sensitive label-free chemiluminescence (CL) immunosensors for the detection of CYFRA21-1. In this work, magnetic core-shell nanocomposite Fe3O4@nickel-cobalt double hydroxide (Fe3O4@DH) was used for the first time as a carrier to synthesize N-(4-aminobutyl)-N-ethylisoluminol (ABEI) and gold and silver nanocluster (AuAgNC) bifunctionalized magnetic nanomaterials Fe3O4@DH/AuAgNCs-ABEI. The resulting Fe3O4@DH/AuAgNCs-ABEI demonstrated excellent CL performance, attributed to the exceptional catalytic capability of nickel-cobalt double hydroxide (NiCo-DH) and AuAgNCs, as well as the large specific surface area of NiCo-DH for AuAgNCs and ABEI enrichment. Moreover, Fe3O4@DH/AuAgNCs-ABEI exhibited superior stability compared to Fe3O4-based CL-functionalized magnetic nanomaterials, owing to the presence of NiCo-DH shells. On this basis, a label-free CL immunosensor using CYFRA21-1 antibody-modified Fe3O4@DH/AuAgNCs-ABEI as an analytical interface was constructed for the detection of CYFRA21-1 in the range from 1.0 × 10-13 to 1.0 × 10-8 g/mL. The detection limit of this CL immunosensor was 47.7 fg/mL, 4 orders of magnitude lower than existing CL methods. The CL immunosensor was able to accurately detect the concentration of CYFRA21-1 in serum samples, as evidenced by ELISA results. More importantly, it not only distinguished well between healthy persons and lung cancer patients (90.0% sensitivity and 90.0% specificity), but also effectively distinguished between patients with non-small cell lung cancer and small cell lung cancer (80.0% sensitivity and 86.7% specificity).

Autoimmune encephalitis with coexisting antibodies to GABABR, GAD65, SOX1 and Ma2.

Autoimmune encephalitis (AE) is a disease caused by an abnormal reaction between the body's autoimmunity and the central nervous system, in which the abnormal immune response targets antigenic components within or on the surface of neuronal cells. The main manifestations are mental and behavioural changes, cognitive impairment, impaired consciousness, seizures, movement disorders, etc. Most cell surface antibodies respond well to immunotherapy, intracellular antibodies, on the other hand, are usually associated with more tumours and are relatively difficult to treat with a poor prognosis. In recent years, autoimmune encephalitis that is positive for multiple anti-neuronal antibodies has been gradually recognized in the clinic, with complex and varied clinical manifestations, especially in combination with malignant tumours, which have worse treatment and prognosis. Current clinical studies on the coexistence of multiple anti-neuronal antibodies in patients with AE are mainly disseminated case reports. Patients with AE in which four anti-neuronal antibodies coexist are even rarer. We report a patient who initially presented with an irritating dry cough and hyponatraemia and a chest CT suspicious for malignancy, followed by progressive deterioration of persistent status epilepticus, consciousness and cognitive deficits, and psycho-behavioural abnormalities. Serum and cerebrospinal fluid antibodies against neuronal surface or intracellular antigens were detected using a cell-based assay (CBA) method. Serum and cerebrospinal fluid were found to be positive for anti-GABABR, GAD65, SOX1 and Ma2 antibodies. And a definitive diagnosis of small cell lung cancer was made by immunohistochemistry. He eventually received gammaglobulin, steroid pulsed therapy and tumour chemotherapy. The coexistence or overlap of multiple anti-neuronal surface antibodies with anti-neuronal intracellular antibodies is rare and increases the likelihood of underlying malignancy. Elucidating the impact of individualized immunotherapy and coexisting antibodies on the clinical presentation of patients has the potential to improve long-term prognosis.

Actin dysregulation induces neuroendocrine plasticity and immune evasion: a vulnerability of small cell lung cancer.

Small cell lung cancer (SCLC) is aggressive with limited therapeutic options. Despite recent advances in targeted therapies and immunotherapies, therapy resistance is a recurring issue, which might be partly due to tumor cell plasticity, a change in cell fate. Nonetheless, the mechanisms underlying tumor cell plasticity and immune evasion in SCLC remain elusive. CRACD, a capping protein inhibitor that promotes actin polymerization, is frequently inactivated in SCLC. Cracd knockout (KO) transforms preneoplastic cells into SCLC tumor-like cells and promotes in vivo SCLC development driven by Rb1, Trp53, and Rbl2 triple KO. Cracd KO induces neuroendocrine (NE) plasticity and increases tumor cell heterogeneity of SCLC tumor cells via dysregulated NOTCH1 signaling by actin cytoskeleton disruption. CRACD depletion also reduces nuclear actin and induces EZH2-mediated H3K27 methylation. This nuclear event suppresses the MHC-I genes and thereby depletes intratumoral CD8+ T cells for accelerated SCLC tumorigenesis. Pharmacological blockade of EZH2 inhibits CRACD-negative SCLC tumorigenesis by restoring MHC-I expression and immune surveillance. Unsupervised single-cell transcriptomics identifies SCLC patient tumors with concomitant inactivation of CRACD and downregulated MHC-I pathway. This study defines CRACD, an actin regulator, as a tumor suppressor that limits cell plasticity and immune evasion and proposes EZH2 blockade as a viable therapeutic.

Plain language summary: tarlatamab for patients with previously treated small cell lung cancer.

This is a summary of a phase 2 clinical study called DeLLphi-301. The study looked at how effective and safe a medicine called tarlatamab was in participants with small cell lung cancer (SCLC). Participants previously received at least two other treatments for their SCLC. Tarlatamab is a new medicine that locates a protein called DLL3 on the cancer, which allows T cells to attack the cancer. T cells belong to the body's natural defense system known as the immune system. The DeLLphi-301 study separated participants into two groups to receive tarlatamab 10mg or 100mg to determine which dose best shrank SCLC with minimal side effects. All participants received a small first dose (1mg tarlatamab) to decrease the risk of an immune system reaction called cytokine release syndrome (CRS). Tarlatamab was given through the participant's vein once every 2weeks. This method of administration is known as intravenous (IV) infusion. In the group given 10mg tarlatamab, 40% of participants responded to treatment (cancer shrank). In the group given 100mg tarlatamab, 32% of participants responded to treatment (cancer shrank). After taking tarlatamab at either dose, 59% of participants lived for at least 6months without their cancer growing or getting worse.The most common side effect was CRS, which occurred in 51% of participants in the group given 10mg tarlatamab and 61% of participants in the group given 100mg tarlatamab. Other common side effects were decreased appetite, fever, constipation, and anemia. Some participants had a type of immune reaction called immune effector cell-associated neurotoxicity syndrome (ICANS). A small number of participants (3%) stopped taking tarlatamab because of side effects related to tarlatamab. The study found that tarlatamab given every 2weeks shrank SCLC in participants with SCLC who received previous treatments. Participants given the 10mg tarlatamab dose had fewer side effects than those given the 100mg tarlatamab dose.Clinical Trial Registration: NCT05740566 (DeLLphi-304) (ClinicalTrials.gov).

Camptothecin and Its Derivatives from Traditional Chinese Medicine in Combination with Anticancer Therapy Regimens: A Systematic Review and Meta-Analysis

Background/Objectives: Camptothecin (CPT) and its derivatives, irinotecan and topotecan, are integral components of cancer chemotherapy, often used in combination therapies. This meta-analysis evaluates the efficacy of CPT-based combination treatments in cancer patients. Methods: We systematically searched the literature database using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist for articles published between 2000 and 2022. Published studies were retrieved through an electronic search on the Web of Science, PubMed, and Google Scholar databases. A total of 138 studies were downloaded and examined, and 71 eligible studies were selected for meta-analysis after excluding studies that did not meet the inclusion criteria. Results: Ultimately, a total of 71 studies were included in the analysis, comprising non-small cell lung cancer (NSCLC), colorectal cancer (COLRC), oesophageal/gastric cancer (O/GC), and small cell lung cancer (SCLC). For NSCLC, the objective response rate (RR) was 31.8% (95% CI: 27.3–37.1%, p = 0.025), with irinotecan plus cisplatin showing significantly higher efficacy compared to other irinotecan-based combinations. In COLRC, irinotecan and 5-fluorouracil/leucovorin plus bevacizumab demonstrated superior efficacy with a RR of 44% (95% CI: 34–58, p &lt; 0.001) and minimal haematological toxicity. In O/GC, irinotecan-based combinations showed an average RR of 43% (95% CI: 27–70, p &lt; 0.001) and average overall survival (OS) and progression-free survival (PFS) rates of 10.2 and 5.5 months, respectively. For SCLC, irinotecan-based combinations had a higher control response than topotecan-based ones, while the latter exhibited higher rates of stable and progressive disease. The overall RR for SCLC was 45% (95% CI: 34.3–60.2, p &lt; 0.001). Conclusions: The existing evidence underscored the potential of CPT-based combination therapy in various cancers. Among the various combinations discussed in this analysis, irinotecan plus cisplatin demonstrated the highest objective RR in 12 trials focused on NSCLC. This study provides valuable insights into potential treatment strategies for various types of cancer, emphasising the importance of personalised and tailored approaches to maximise efficacy and minimise adverse effects.

NCMP-26. PATIENTS WITH ANTI-HU/ANNA1 PARANEOPLASTIC NEUROLOGICAL DISORDERS DEVELOP PROGRESSIVE DISABILITY BUT HAVE INCREASED SURVIVAL

Abstract ANNA-1/Hu-IgG paraneoplastic neurological disorders (PND) are rare and factors associated with disability and survival outcomes are unknown. We aimed to 1) examine disability and survival in ANNA1/Hu-IgG PND and 2) compare survival to a control group of small cell lung cancer (SCLC) without PND. METHODS This is a retrospective cohort study of ANNA1/Hu-IgG+ with PND and a control cohort of SCLC without PND (n=1513). Cox proportional hazard models examined clinical predictors of disability and survival. Kaplan-Meier curves examined time to mortality and mRS&amp;gt;2. Cox proportional hazard models compared survival between ANNA1/Hu-IgG PND and SCLC without PND, adjusting for age, sex, cancer stage, and brain metastases. RESULTS Forty-five patients with ANNA/Hu1-IgG PND were included (73% female, mean age=63 years [SD=13]). Phenotypes included; neuropathy (16, 36%), ataxia (11, 24%), encephalitis (10, 22%), myasthenic syndromes (3, 7%), myelopathy (2, 4%), enteric neuropathy (2, 4%), myoclonus (1, 2%). Cancers were identified in 78%; SCLC (26, 74%), non-SCLC (4, 11%), other (5, 14%). Immunosuppressive therapy for PND was given in 53%. At 5-year follow-up, 74% had mRS&amp;gt;2. Limbic encephalitis had greater hazard of mRS&amp;gt;2 at last follow-up (HR=7.76, [95% CI=2.20-27.39], p=0.001). At 5-year follow-up, 58% had died. Survival was not influenced by phenotype nor immunosuppressive treatment. Patients with SCLC and ANNA1/Hu-IgG (n=26) were compared to SCLC without PND (n=1513) and had 54% lower hazard of death (adjusted HR =0.46, [95% CI = 0.28–0.76], p=0.003). In ANNA-1/Hu-IgG PND, most patients experienced disability and greater disability was associated with limbic encephalitis, suggesting a potential modifiable factor. However, patients with SCLC and ANNA1/Hu-IgG PND survived longer than patients with SCLC without ANNA1/Hu-IgG PND, suggesting a possible survival advantage due to earlier cancer detection (lead time bias) and/or increased antitumor immunity.

CNSC-61. NEURONAL-ACTIVITY DEPENDENT MECHANISMS OF SMALL CELL LUNG CANCER PATHOGENESIS

Abstract Neural activity is increasingly recognized as a crucial regulator of cancer growth. In the brain, neuronal activity robustly influences glioma growth both through paracrine mechanisms and through electrochemical integration of malignant cells into neural circuitry via neuron-to-glioma synapses. Outside of the CNS, innervation of tumors such as prostate, breast, pancreatic, and gastrointestinal cancers by peripheral nerves similarly regulates cancer progression. However, the extent to which the nervous system regulates lung cancer progression, either in the lung or when metastatic to the brain, is less well understood. Small cell lung cancer (SCLC) is a lethal high-grade neuroendocrine tumor that exhibits a strong propensity to metastasize to the brain. Here we demonstrate that SCLC cells in the brain co-opt neuronal activity-regulated mechanisms to stimulate growth and progression. With in vivo optogenetic stimulation, we show that glutamatergic and GABAergic cortical neuronal activity each drive proliferation of SCLC through both paracrine and synaptic neuron-cancer interactions. In the brain, SCLC cells form bona fide neuron-to-SCLC synapses evident on immunoelectron microscopy for the first time for non-brain derived malignancy. Using electrophysiology and two-photon calcium imaging, we find that SCLC cells exhibit depolarizing currents with consequent calcium transients in response to neuronal activity. SCLC cell membrane depolarization is sufficient to promote the growth of intracranial tumors. We also demonstrate reciprocal effects of SCLC on neurons, manifesting as increased neuronal synaptogenesis and elevated field potentials in regions of the tumor. Finally, in the lung, vagus nerve transection markedly inhibits primary lung tumor formation and development and awards survival benefit in spontaneous genetic SCLC model, highlighting a critical role for innervation in overall SCLC growth. Taken together, these studies illustrate that neuronal activity plays a crucial role in dictating SCLC pathogenesis in both the lung and the brain.

RADT-47. CLINICAL OUTCOMES AFTER SURGICAL RESECTION OF BRAIN METASTASES IN SMALL CELL LUNG CANCER PATIENTS

Abstract Small cell lung cancer (SCLC) has a high propensity to metastasize to the brain. Radiotherapy is the primary treatment for SCLC brain metastases. Whole brain radiotherapy (WBRT) has been the standard of care, but recent studies show similar overall survival (OS) in patients treated with upfront stereotactic radiosurgery (SRS). Surgery does not typically have a role in SCLC although it can provide relief of neurologic symptoms and pathologic diagnosis. We sought to determine the clinical outcomes of patients who underwent surgical resection of SCLC brain metastases. A retrospective chart review of SCLC patients treated at UPMC from 2010 – 2022 was performed. OS after resection was estimated using the Kaplan-Meier method with log-rank test. 4,213 patients were diagnosed with SCLC, of which 715 patients (17%) had synchronous brain metastases at initial diagnosis. Forty patients underwent resection of SCLC brain metastases, all of whom were symptomatic. The median diameter of the resected brain metastases was 3.8 cm (range 1.7 – 8 cm). Seventy-five percent (n=30) had resection of synchronous brain metastases and 25% (n=10) had resection of metachronous brain metastases. Median OS for the surgical cohort was 13.6 months (interquartile range (IQR), 3.4 – 21.9 months). Patients with metachronous and synchronous brain metastases had median OS of 6.8 months (IQR, 2.8 – 24.6 months) and 14.3 months (IQR, 3.6 – 20.4), respectively. Of patients with synchronous brain metastases (n=30), 53% (n=16) received post-operative WBRT, 40% (n=11) received post-operative SRS and 10% (n=3) died within 7 weeks of surgery. Median OS of patients with synchronous brain metastases treated with WBRT and SRS were 11.9 months (IQR, 3.8 – 21.7) and 19.0 months (IQR, 14.6 – 30.3), respectively, and the difference was not statistically significant (p=0.53). Surgery for SCLC brain metastases is uncommon. Patients who received SRS versus WBRT post-operatively for synchronous brain metastases had no difference in OS.

RepID as a potential biomarker and therapeutic target for lung neuroendocrine tumor

Neuroendocrine tumor (NET) is a rare malignant tumor, notably small cell lung cancer (SCLC), a type of lung neuroendocrine tumor, which has a survival rate of less than 7%. Although various biomarkers including CHGA (Chromogranin A), INSM1 (Insulinoma-associated protein 1), and SYP (Synaptophysin) are extensively used for the diagnostic testing of NET, their diverse specificities and sensitivities are acknowledged as limitations. Here, we demonstrate that RepID (Replication initiation determinant protein), a component of CRL4 (Cullin-RING ubiquitin E3 ligase 4), holds promise as a biomarker for identifying NET and SCLC. Analysis of the Cancer Cell Line Encyclopedia (CCLE) via the CellMinerCDB portal reveals a high correlation between RepID transcript levels and mRNA expression of NE signature genes. Additionally, RepID protein is highly expressed in SCLC patient tissues and a subset of SCLC cell lines. Viability analysis following treatment with pevonedistat and SZL-P1-41 in SCLC cell lines and human SCLC-organoid models indicates that RepID expression determines the sensitivity to CRL-targeting anti-cancer drugs. These findings suggest that RepID represents a novel biomarker for NET and SCLC, and insights from RepID research in these cancers could lead to innovative therapeutic strategies.

Gastroesophageal reflux disease and risk of incident lung cancer: A large prospective cohort study in UK Biobank.

Some pathogenic mechanisms suggest a potential relationship between gastroesophageal reflux disease (GERD) and respiratory diseases. However, evidence regarding the association between GERD and lung cancer is mixed. We aim to explore this relationship based on data from the large-scale UK Biobank study. We performed a cross-sectional and prospective cohort study in 501,569 (45.58% male) individuals included in the UK Biobank at baseline (2006-2010). The Cox proportional hazards model and logistic regression models were used to assess the relationship between GERD and lung cancer, small cell lung cancer (SCLC), lung squamous cell carcinoma (LUSC), and lung adenocarcinoma (LUAD). During a mean follow-up of 11.54 years, 3,863 (0.84%) incident lung cancer cases were identified. In the cross-sectional analysis using logistic models, significant associations were found between GERD and prevalent lung cancer cases (odds ratio [OR] = 1.87, 95% confidence interval [95% CI]: 1.45-2.38) and subtypes of lung cancer, with an OR (95% CI) of 3.19 (1.47-6.79) for SCLC, 2.08 (1.33-3.21) for LUSC, 1.85 (1.15-2.91) for LUAD. In the follow-up analysis using Cox models, GERD was associated with an increased risk of lung cancer (hazard ratio [HR] = 1.24, 95%CI: 1.14-1.34). Similar associations were also observed between GERD and SCLC (HR = 1.39, 95% CI: 1.09-1.78), LUSC (HR = 1.40, 95% CI: 1.18-1.65), and LUAD (HR = 1.17, 95% CI: 1.02-1.33). The risk of lung cancer resulting from GERD was mainly elevated in former smokers (HR = 1.38, 95% CI: 1.23-1.54) and current smokers (HR = 1.18, 95% CI: 1.04-1.34), but not in never-smokers (HR = 0.89, 95% CI: 0.70-1.14). No significant association was observed in former smokers who had quit smoking for at least 25 years. We found that GERD was positively associated with an increased risk of lung cancer, especially among smokers. Awareness of this association may be beneficial for prevention and treatment strategies of both diseases.

Evaluation of Potential EGFR Inhibitors for Non-small Cell Lung Cancer: A Structure-based Virtual Screening and Molecular Dynamics Study

Non-small cell lung cancer is a leading cause of cancer deaths globally. EGFR is one of the attractive drug targets for non small cell lung cancer. It was first identified receptor tyrosine kinase receptor. It plays a critical role in the variety of biological activity apoptosis, cell cycle progression, differentiation, development, and transcription. Somatic mutation occurs in human EGFR. After that the normal function of EGFR was over expressed can leads to develop lung cancer. In this study we have identified three potential compounds using structure based virtual screening. Then thus compounds were evaluated ADME properties, all the compounds are under acceptable range with predicted ADME properties, then thus protein-ligand complex stability were carried out using Gromacs. The stability of the protein-ligand complex is stable throughout entire simulation, especially MET 769 is significant for stability of the complex. Furthermore, invitro cytotoxicity assay were performed for the best one compounds against non small cell lung cancer cell line.