Impact of thoracic radiotherapy on first-line treatment outcomes in ES-SCLC patients.

BACKGROUND: The therapeutic advantage of thoracic radiotherapy (tRT) as an adjunct to first-line immunotherapy and chemotherapy in patients with extensive-stage small cell lung cancer (ES-SCLC) remains unclear. We sought to elucidate this in a retrospective cohort study comparing the effectiveness and safety of tRT in combination with first-line immunotherapy and chemotherapy. METHODS: Our retrospective study included patients with ES-SCLC, treated at the West China Hospital between January 2019 and December 2022. They received first-line immunotherapy and chemotherapy and were categorized into two cohorts based on the administration of tRT. The primary outcomes were overall survival (OS) and progression-free survival (PFS). Cox regression analysis was utilized to identify potential independent predictors of prognosis and to compare the treatment outcomes across various patient subgroups. Treatment-related toxicities across both cohorts were compared using the Chi-squared test. RESULTS: A total of 99patients were eligible for the study, out of which 55 received tRT. The medianduration of follow-up was 39 months. Remarkably, patients who received tRTdemonstrated superior OS and PFS in comparison to those who did not (P < 0.05). Subgroup analysis further confirmed these findings. Multivariate analysisidentified treatment group and liver metastasis as independent prognosticfactors (P < 0.05). The incidence of grade 3-4 adverse events showed nostatistically significant difference between the two cohorts. CONCLUSIONS: Thus, weconfirmed that the addition of tRT to the conventional regimen of first-linechemotherapy and immunotherapy yields better survival outcomes without asignificant increase in toxicity.

Early Circulating Tumor DNA Shedding Kinetics for Prediction of Platinum Sensitivity in Patients With Small Cell Lung Cancer.

PURPOSE: Small cell lung cancer (SCLC) is characterized by rapid progression after platinum resistance. Circulating tumor (ctDNA) dynamics early in treatment may help determine platinum sensitivity. MATERIALS AND METHODS: Serial plasma samples were collected from patients receiving platinum-based chemotherapy for SCLC on the first 3 days of cycle one and on the first days of subsequent cycles with paired samples collected both before and again after infusions. Tumor-informed plasma analysis was carried out using CAncer Personalized Profiling by deep Sequencing (CAPP-Seq). The mean variant allele frequency (VAF) of all pretreatment mutations was tracked in subsequent blood draws and correlated with radiologic response. RESULTS: ctDNA kinetics were assessed in 122 samples from 21 patients. Pretreatment VAF did not differ significantly between patients who did and did not respond to chemotherapy (mean 22.5% v 4.6%, P = .17). A slight increase in ctDNA on cycle 1, day 1 immediately post-treatment was seen in six of the seven patients with available draws (fold change from baseline: 1.01-1.44), half of whom achieved a response. All patients who responded had a >2-fold decrease in mean VAF on cycle 2 day 1 (C2D1). Progression-free survival (PFS) and overall survival (OS) were significantly longer in patients with a >2-fold decrease in mean VAF after one treatment cycle (6.8 v 2.6 months, log-rank P = .0004 and 21.7 v 6.4 months, log rank P = .04, respectively). CONCLUSION: A >2-fold decrease in ctDNA concentration was observed by C2D1 in all patients who were sensitive to platinum-based therapy and was associated with longer PFS and OS.

Potential therapeutic option for EGFR-mutant small cell lung cancer transformation: a case report and literature review.

Transformation from non-small cell lung cancer (NSCLC) to small cell lung cancer (SCLC) is rare and is associated with poor prognosis. However, the standard treatment protocols for patients with SCLC transformation remain unknown. Here, we report the case of a patient with advanced EGFR exon 19 deletion (19del) NSCLC who underwent SCLC transformation during targeted therapy. Biopsies and genetic testing were performed to adjust treatment regimens accordingly. The patient responded favorably to a combined treatment regimen comprising etoposide plus cisplatin chemotherapy and adebrelimab plus osimertinib. This case highlights the critical importance of acknowledging tumor heterogeneity in clinical decision-making and identifying potentially effective treatment options for patients with SCLC transformation. Additionally, we reviewed cases of the transformation of NSCLC to SCLC from 2017 to 2023.

Combination of arsenic trioxide and apatinib synergistically inhibits small cell lung cancer by down-regulating VEGFR2/mTOR and Akt/c-Myc signaling pathway via GRB10.

BACKGROUND: Small cell lung carcinoma (SCLC) is characterized by -poor prognosis, -high predilection for -metastasis, -proliferation, and -absence of newer therapeutic options. Elucidation of newer pathways characterizing the disease may allow for development of targeted therapies and consequently favorable outcomes. METHODS: The current study explored the combinatorial action of arsenic trioxide (ATO) and apatinib (APA) in vitro and in vivo. In vitro models were tested using -H446 and -H196 SCLC cell lines. The ability of drugs to reduce -metastasis, -cell proliferation, and -migration were assessed. Using bioinformatic analysis, differentially expressed genes were determined. Gene regulation was assessed using gene knock down models and confirmed using Western blots. The in vivo models were used to confirm the resolution of pathognomic features in the presence of the drugs. Growth factor receptor bound protein (GRB) 10 expression levels of human small cell lung cancer tissues and adjacent tissues were detected by IHC. RESULTS: In combination, ATO and APA were found to significantly reduce -cell proliferation, -migration, and -metastasis in both the cell lines. Cell proliferation was found to be inhibited by activation of Caspase-3, -7 pathway. In the presence of drugs, it was found that expression of GRB10 was stabilized. The silencing of GRB10 was found to negatively regulate the VEGFR2/Akt/mTOR and Akt/GSK-3ß/c-Myc signaling pathway. Concurrently, absence of metastasis and reduction of tumor volume were confirmed in vivo. The immunohistochemical results confirmed that the expression level of GRB10 in adjacent tissues was significantly higher than that in human small cell lung cancer tissues. CONCLUSIONS: Synergistically, ATO and APA have a more significant impact on inhibiting cell proliferation than each drug independently. ATO and APA may be mediating its action through the stabilization of GRB10 thus acting as a tumor suppressor. We thus, preliminarily report the impact of GRB10 stability as a target for SCLC treatment.

Phase Ib/II study on the safety, tolerability, and preliminary efficacy of pegylated irinotecan (JK1201I) as second-line monotherapy for patients with small-cell lung cancer.

PURPOSE: To evaluate the safety, tolerability, and preliminary efficacy of multiple doses of pegylated irinotecan (JK1201I) as a second-line monotherapy for treating small-cell lung cancer (SCLC) patients. METHODS: According to the "3 + 3" dose-escalation principle, patients received intravenous JK1201I at 180 or 220 mg/m2 once every 3 weeks for four cycles. Progression-free survival (PFS), overall survival (OS), median progression-free survival (mPFS), and median overall survival (mOS) were evaluated. The Kaplan-Meier method was used to analyze PFS and overall OS. Brookmeyer and Crowley's method was used for mPFS and mOS. RESULTS: This study included 29 patients with stage III-IV SCLC (stage IIIa, n = 1; stage IIIb, n = 1; and stage IV, n = 27). Of these, 26 patients were enrolled in the 180 mg/m2 dose group, and 3 patients were enrolled in the 220 mg/m2 dose group. No dose-limiting toxicity (DLT) was noted during the first 28 days of treatment. Grade 3 or higher adverse events were recorded in the 180 mg/m2 group, including diarrhea (11.5%, 3/26), neutropenia (7.7%, 2/26), and leukopenia (7.7%, 2/26). In the 220 mg/m2 group, one patient (33.3%, 1/3) experienced neutropenia or leukopenia. In the 180 mg/m2 group, 38.5% (10/26) of patients achieved an objective response rate (ORR), with a disease control rate (DCR) of 73.1% (19/26). The mPFS and mOS were 3.4 and 12.1 months, respectively. In the 220 mg/m2 group, one patient had stable disease, and one had progressive disease (PD). The ORR, DCR, mPFS, and mOS were 0% (0/3) and 33.3% (1/3), 2.7 months and 2.7 months, respectively. CONCLUSION: JK1201I exhibits promising efficacy and relatively low toxicities as a second-line monotherapy for SCLC, warranting further large-scale clinical studies to evaluate its efficacy in greater detail.

Integration of clinical and blood parameters in risk prognostication for patients receiving immunochemotherapy for extensive stage small cell lung cancer: real-world data from two centers.

BACKGROUND: Immune checkpoint inhibitors (ICIs) had modest advances in the treatment of extensive-stage small cell lung cancer (ES-SCLC) in clinical trials, but there is a lack of biomarkers for prognosis in clinical practice. METHODS: We retrospectively collected data from ES-SCLC patients who received ICIs combined chemotherapy from two centers in China, integrated clinical and blood parameters, and constructed risk prognostication for immunochemotherapy. The population was divided into high- and low-risk groups, and the performance of the model was assessed separately in the training and validation cohorts. RESULTS: Two hundred and twenty and 43 patients were included in the training and validation groups, respectively. The important predictors were screened including body mass index, liver metastases, coefficient variation of red blood cell distribution width, lactate dehydrogenase, albumin, and C-reactive protein. Predicting 1-year overall survival (OS), the AUC values under ROC for the model under training, internal validation, and external validation were 0.760, 0.732, and 0.722, respectively, and the calibration curve and clinical decision curve performed well. Applied the model to divide patients into low-risk and high-risk groups, and the median OS was 23.7 months and 9.1 months, and the median progression-free survival was 8.2 months and 4.8 months, respectively; furthermore, this ability to discriminate survival was also observed in the validation cohort. CONCLUSIONS: We constructed a novel prognostic model for ES-SCLC to predict survival employing baseline tumor burden, nutritional and inflammatory parameters, it is easily measured to screen high-risk patient populations.

A retrospective evaluation of therapeutic efficacy and safety of chemoradiotherapy in older patients (aged ≥ 75 years) with limited-disease small cell lung cancer: insights from two institutions and review of the literature.

BACKGROUND: The standard treatment for patients in good general condition with limited-disease small cell lung cancer (LD-SCLC) is concurrent platinum/etoposide chemotherapy and thoracic radiotherapy (TRT). However, the efficacy and safety of chemoradiotherapy (CRT) in older patients with LD-SCLC has not been fully explored; moreover, the optimal treatment for this patient group remains unclear. This study aimed to investigate the feasibility and efficacy of CRT in older patients with LD-SCLC. PATIENTS AND METHODS: From April 2007 to June 2021, consecutive older patients (aged ≥ 75 years) with stage I to III SCLC who received concurrent or sequential CRT at two institutions were retrospectively evaluated for efficacy and toxicity of CRT. RESULTS: A total of 32 older patients underwent concurrent (n = 19) or sequential (n = 13) CRT for LD-SCLC. The median ages of the patients in the concurrent and sequential CRT groups were 77 (range: 75-81) years and 79 (range: 76-92) years, respectively. The median number of chemotherapeutic treatment cycles was four (range, 1-5), and the response rate was 96.9% in all patients (94.7% in concurrent and 100% in sequential CRT groups). The median progression-free survival (PFS) and median overall survival (OS) for all patients were 11.9 and 21.1 months, respectively. The median PFS was 13.0 and 9.0 months in the concurrent CRT and sequential CRT groups, respectively, with no statistically significant difference (p = 0.67). The median OS from the initiation of CRT was 19.2 and 23.5 months in the concurrent and sequential CRT groups, respectively (p = 0.46). The frequencies of Grade ≥ 3 hematological adverse events were as follows: decreased white blood cell count, 20/32 (62.5%); decreased neutrophil count, 23/32 (71.9%); anemia, 6/32 (18.8%); decreased platelet count, 7/32 (21.9%); and febrile neutropenia, 3/32 (9.4%). Treatment-related deaths occurred in one patient from each group. CONCLUSIONS: Although hematological toxicities, particularly reduced neutrophil count, were severe, CRT showed favorable efficacy in both concurrent and sequential CRT groups. However, concurrent CRT may not be feasible for all older patients with LD-SCLC; accordingly, sequential CRT may be considered as a treatment of choice for these patients. Further prospective trials are warranted to identify optimal treatment strategies for this patient group.

The effect of pulmonary rehabilitation on quality of life and functional capacity after chemotherapy in patients with small cell lung cancer.

OBJECTIVE: This study aimed to investigate the effect of pulmonary rehabilitation on quality of life during the survival period in individuals with small cell lung cancer. METHODS: Thirty-six patients with a diagnosis of small cell lung cancer (SCLC), who completed chemotherapy treatment and were in the survival period, were included in the study. A pulmonary rehabilitation program was applied to individuals at 40-70% of submaximal heart rate, 3 days a week for 8 weeks. The pulmonary rehabilitation program will consist of warm up, breathing exercises, gait training, aerobic exercises, and cool down exercises. Demographic information, walking distance, and presence of dyspnea were questioned. Inspiration/expiration difference was evaluated. Vital signs were evaluated before each session. Quality of life was assessed with the Cancer-Specific Developed Quality of Life Scale (EORTC-QLQ-C30). RESULTS: Of the patients, 80% (36 people) completed the entire 8-week program. The mean age of the individuals was 51.78 ± 10.23. In the evaluation made at the end of the rehabilitation program, it was observed that the walking distance of the individuals increased significantly. Inspiration of individuals' expiratory difference increased by an average of 2.01 ± 0.40 cm. Improvement was found in the sub-parameters of quality of life (p < 0.05). SIGNIFICANCE OF RESULTS: The participants with small cell lung cancer had decreased quality of life due to long-term immobilization, surgery, hospitalization times, side effects of chemotherapy treatment, and other problems. Regular exercise programs can provide an increase in the individual's pulmonary functions. Individual-specific pulmonary rehabilitation programs have important contributions to the quality of life in SCLC on the survival period, and it has shown that this study can guide physiotherapists and physicians working in oncological rehabilitation and pulmonary rehabilitation.

What is the Reason That the Pharmacological Future of Chemotherapeutics in the Treatment of Lung Cancer Could Be Most Closely Related to Nanostructures? Platinum Drugs in Therapy of Non-Small and Small Cell Lung Cancer and Their Unexpected, Possible Interactions. The Review.

Over the course of several decades, anticancer treatment with chemotherapy drugs for lung cancer has not changed significantly. Unfortunately, this treatment prolongs the patient's life only by a few months, causing many side effects in the human body. It has also been proven that drugs such as Cisplatin, Carboplatin, Oxaliplatin and others can react with other substances containing an aromatic ring in which the nitrogen atom has a free electron group in its structure. Thus, such structures may have a competitive effect on the nucleobases of DNA. Therefore, scientists are looking not only for new drugs, but also for new alternative ways of delivering the drug to the cancer site. Nanotechnology seems to be a great hope in this matter. Creating a new nanomedicine would reduce the dose of the drug to an absolute minimum, and thus limit the toxic effect of the drug; it would allow for the exclusion of interactions with competitive compounds with a structure similar to nucleobases; it would also permit using the so-called targeted treatment and bypassing healthy cells; it would allow for the introduction of other treatment options, such as radiotherapy directly to the cancer site; and it would provide diagnostic possibilities. This article is a review that aims to systematize the knowledge regarding the anticancer treatment of lung cancer, but not only. It shows the clear possibility of interactions of chemotherapeutics with compounds competitive to the nitrogenous bases of DNA. It also shows the possibilities of using nanostructures as potential Platinum drug carriers, and proves that nanomedicine can easily become a new medicinal product in personalized medicine.

Theranostics with somatostatin receptor antagonists in SCLC: Correlation of 68Ga-SSO120 PET with immunohistochemistry and survival.

Rationale: Positron Emission Tomography (PET) using the somatostatin receptor 2 (SSTR2)-antagonist satoreotide trizoxetan (68Ga-SSO120) is a novel, promising imaging modality for small-cell lung cancer (SCLC), which holds potential for theranostic applications. This study aims to correlate uptake in PET imaging with SSTR2 expression in immunohistochemistry (IHC) and to assess the prognostic value of 68Ga-SSO120 PET at initial staging of patients with SCLC. Methods: We analyzed patients who underwent 68Ga-SSO120 PET/CT during initial diagnostic workup of SCLC as part of institutional standard-of-care. SSTR2 expression in IHC was evaluated on a 4-level scale and correlated with normalized standardized uptake values and tumor-to-liver ratios (SUVmax and TLRpeak) in 68Ga-SSO120 PET on a lesion level. Highest lesion SUVmax/TLRpeak per patient, SSTR2 score in IHC, M status according to TNM classification, and other parameters were analyzed for association with overall survival (OS) and time to treatment failure (TTF) by univariate, multivariate (cut-off values were identified on data for best separation), and stratified Cox regression. Results: We included 54 patients (24 men/30 women, median age 65 years, 21 M0/33 M1 according to TNM classification). In 43 patients with available surplus tumor tissue samples, hottest lesion SUVmax/TLRpeak showed a significant correlation with the level of SSTR2-expression by tumor cells in IHC (Spearman's rho 0.86/0.81, both p < 0.001; ANOVA p < 0.001). High SSTR2 expression in IHC, 68Ga-SSO120 SUVmax and TLRpeak of the hottest lesion per patient, whole-body TLRmean, MTV, TLG, M status, and serum LDH showed a significant association with inferior TTF/OS in univariate analysis. In separate multivariate Cox regression (including sex, age, M stage, and LDH) higher hottest-lesion TLRpeak showed a significant association with shorter OS (HR = 0.26, 95%CI: 0.08-0.84, p = 0.02) and SSTR2 expression in IHC with significantly shorter TTF (HR = 0.24, 95%CI: 0.08-0.71, p = 0.001) and OS (HR = 0.22, 95%CI: 0.06-0.84, p = 0.03). In total, 12 patients (22.2%) showed low (< 1), 21 (38.9%) intermediate (≥ 1 but < 2), 14 (25.9%) high (≥ 2 but < 5), and 7 (13.0%) very high (≥ 5) whole-body mean TLRmean. Conclusion: In patients with SCLC, SSTR2 expression assessed by 68Ga-SSO120 PET and by IHC were closely correlated and associated with shorter survival. More than 75% of patients showed higher whole-body 68Ga-SSO120 tumor uptake than liver uptake and almost 40% high or very high uptake, possibly paving the way towards theranostic applications.

Sintilimab combined with anlotinib and chemotherapy as second-line or later therapy in extensive-stage small cell lung cancer: a phase II clinical trial.

Treatment options for patients with relapsed extensive-stage small cell lung cancer (ES-SCLC) remain scarce. This study aims to evaluate the efficacy and safety of combining anlotinib and sintilimab plus chemotherapy as a second line or later therapy for ES-SCLC patients. This is a phase II clinical trial (ChiCTR2100049390) conducting at Shandong Cancer Hospital. Patients with ES-SCLC and received at least one prior systemic treatment were enrolled. The trial design involved a combination therapy (sintilimab, anlotinib, and nab-paclitaxel) administered over six 21-day cycles, followed by maintenance sintilimab therapy. The primary endpoint was objective response rate (ORR). Circulating tumor DNA sequencing was employed for exploratory analysis. From July 2021 to April 2023, 25 eligible patients were enrolled. The confirmed ORR was 60% (95% CI: 38.7-78.9%) and the DCR was 76% (95% CI: 54.9-90.6%). The mPFS was 6.0 months (95% CI: 5.4-9.7), and the 6-month PFS rate was 49.2%. The mOS was 13.4 months (95% CI: 11.8-NR), with a 12-month survival rate of 62.2%. Treatment-related adverse events (TRAEs) of any grade occurred in 80% of patients, with the most common being fatigue (40%) and nausea (32%). TRAEs of Grade 3 or higher were reported in 12% of patients. ctDNA analysis indicated that low on-treatment blood tumor mutation burden was associated with longer PFS and OS and a potential role of KMT2D mutation in treatment resistance. This combination therapy shows promising efficacy and a manageable safety profile as a second-line or later treatment for ES-SCLC, with genomic insights providing potential biomarkers for treatment response.

Phase I/II trial of plinabulin in combination with nivolumab and ipilimumab in patients with recurrent small cell lung cancer (SCLC): Big ten cancer research consortium (BTCRC-LUN17-127) study.

BACKGROUND: Plinabulin is a GEF-H1 releasing agent with an immune-enhancing function. We report results from a multicenter Phase I/II study (NCT03575793) assessing plinabulin in combination with nivolumab and ipilimumab for the treatment of recurrent SCLC. METHODS: In Phase I, patients were enrolled using a 3 + 3 design to determine dose-limiting toxicities (DLTs) and recommended Phase 2 dose (RP2D). Patients received nivolumab (1 mg/kg), ipilimumab (3 mg/kg), and plinabulin (in escalating doses) on day 1 of each 21-day cycle for 4 cycles followed by maintenance with plinabulin and nivolumab. In phase II, patients with recurrent PD(L)1 inhibitor resistant SCLC were enrolled. The primary objective was median progression-free survival (PFS). RESULTS: Between 9/2018 and 2/2023, 39 patients were enrolled, and 36 patients received study treatment and were evaluable for safety (16 in Phase I; 20 in Phase II). In the phase I dose-escalation, there were 2 DLTs; grade 3 altered mental status lasting <24 h and grade 3 infusion reaction. The Plinabulin RP2D was determined to be 30 mg/m2. Common TRAEs were vomiting (44 %), nausea (42 %), and infusion reaction (36 %); 6 % of patients had a ≥grade 3 TRAE. Five patients (14 %) had ≥grade 3 irAEs; there were no cases of immune-related pneumonitis. In the efficacy analysis in 27 patients, the median PFS was 1.6 months (95 % CI 1.2 to 2.7) and the trial did not meet the pre-specified target median PFS of 3.5 months. Four patients treated at 30 mg/m2 had PR (confirmed 1, unconfirmed 3); 5 patients had SD with a CBR of 33 %. Two of 8 patients treated in phase I at the lower 20 mg/m2 dose had confirmed PR, with 1 patient on the drug regimen for >90 cycles. The median OS and follow-up time were 5.5 months and 2.5 months respectively. CONCLUSIONS: Plinabulin in combination with nivolumab and ipilimumab was tolerable at the dose of 30 mg/m2. While the clinical responses in PD-1 resistant SCLC were limited, some patients had a long duration of response. The number of ≥grade 3 irAE with the combination were lower than expected.

A Newly Developed Anti-L1CAM Monoclonal Antibody Targets Small Cell Lung Carcinoma Cells.

Few effective treatments are available for small cell lung cancer (SCLC), indicating the need to explore new therapeutic options. Here, we focus on an antibody-drug conjugate (ADC) targeting the L1 cell adhesion molecule (L1CAM). Several publicly available databases reveal that (1) L1CAM is expressed at higher levels in SCLC cell lines and tissues than in those of lung adenocarcinoma and (2) the expression levels of L1CAM are slightly higher in SCLC tissues than in adjacent normal tissues. We conducted a series of in vitro experiments using an anti-L1CAM monoclonal antibody (termed HSL175, developed in-house) and the recombinant protein DT3C, which consists of diphtheria toxin lacking the receptor-binding domain but containing the C1, C2, and C3 domains of streptococcal protein G. Our HSL175-DT3C conjugates theoretically kill cells only when the conjugates are internalized by the target (L1CAM-positive) cells through antigen-antibody interaction. The conjugates (an ADC analog) were effective against two SCLC-N (NEUROD1 dominant) cell lines, Lu-135 and STC-1, resulting in decreased viability. In addition, L1CAM silencing rendered the two cell lines resistant to HSL175-DT3C conjugates. These findings suggest that an ADC consisting of a humanized monoclonal antibody based on HSL175 and a potent anticancer drug would be effective against SCLC-N cells.

Expression Analysis of SSTR 1, 2 and 3 in Small-cell Lung Cancer Patients as Targets for Future Peptide Receptor Radionuclide Therapy.

BACKGROUND/AIM: Small-cell lung cancer (SCLC) is noted for its high proliferative rate, and while treatable, relapse is common. SCLC is known to potentially express somatostatin receptors (SSTRs). Somatostatin possesses antineoplastic activity through cell-cycle arrest and apoptosis, and angiogenesis inhibition. SSTRs, thus, serve as potential anticancer targets for somatostatin analogue therapies. The aim of the study was to determine the expression rate of SSTR subtypes 1, 2 and 3 in SCLC using immunohistochemistry, and potential predictors of such rates. MATERIALS AND METHODS: A total of 147 human, SCLC paraffin-embedded tissue microarrays with corresponding patient age, sex, TNM staging, and disease stage were utilized. Immunohistochemical analysis was performed using anti-SSTR 1, 2 and 3 antibodies, each calibrated using healthy human pancreatic islets as positive controls. Array slides were counterstained with hematoxylin and scored based on stain intensity and percentage of stained cells. RESULTS: No SCLC samples expressed SSTR 1, whereas SSTR 2 and 3 were expressed in 29.4% and 4.35% of cases respectively. While females had higher expression levels of SSTR 2/3, and there was a trend of decreased SSTR 2 expression with increased age, results were not statistically significant. No correlation between disease stage and SSTR expression was found. Co-expression of both SSTR2 and 3 occurred in 5.3% of patients. CONCLUSION: Immunohisto-chemistry is an efficient screening tool to reveal optimum SCLC patients for somatostatin analogue therapy. Whilst there currently exist no accepted norm or predictors of SSTR expression levels in SCLC patients, this study contributes insight into the receptors' varied expression.

Jumonji histone demethylases are therapeutic targets in small cell lung cancer.

Small cell lung cancer (SCLC) is a recalcitrant cancer of neuroendocrine (NE) origin. Changes in therapeutic approaches against SCLC have been lacking over the decades. Here, we use preclinical models to identify a new therapeutic vulnerability in SCLC consisting of the targetable Jumonji lysine demethylase (KDM) family. We show that Jumonji demethylase inhibitors block malignant growth and that etoposide-resistant SCLC cell lines are particularly sensitive to Jumonji inhibition. Mechanistically, small molecule-mediated inhibition of Jumonji KDMs activates endoplasmic reticulum (ER) stress genes, upregulates ER stress signaling, and triggers apoptotic cell death. Furthermore, Jumonji inhibitors decrease protein levels of SCLC NE markers INSM1 and Secretogranin-3 and of driver transcription factors ASCL1 and NEUROD1. Genetic knockdown of KDM4A, a Jumonji demethylase highly expressed in SCLC and a known regulator of ER stress genes, induces ER stress response genes, decreases INSM1, Secretogranin-3, and NEUROD1 and inhibits proliferation of SCLC in vitro and in vivo. Lastly, we demonstrate that two different small molecule Jumonji KDM inhibitors (pan-inhibitor JIB-04 and KDM4 inhibitor SD70) block the growth of SCLC tumor xenografts in vivo. Our study highlights the translational potential of Jumonji KDM inhibitors against SCLC, a clinically feasible approach in light of recently opened clinical trials evaluating this drug class, and establishes KDM4A as a relevant target across SCLC subtypes.

Targeting TREX1 Induces Innate Immune Response in Drug-Resistant Small-Cell Lung Cancer.

Small-cell lung cancer (SCLC) is the most lethal type of lung cancer. Paradoxically, this tumor displays an initial exquisite response to chemotherapy; however, at relapse, the tumor is highly resistant to subsequent available therapies. Here, we report that the expression of three prime repair exonuclease 1 (TREX1) is strongly induced in chemoresistant SCLCs. Assay for transposase-accessible chromatin using sequencing and chromatin immunoprecipitation sequencing revealed a significant increase in chromatin accessibility and transcriptional activity of TREX1 gene locus in chemoresistant SCLCs. Analyses of human SCLC tumors and patient-derived xenografts (PDX) also showed an increase in TREX1 expression in postchemotherapy samples. TREX1 depletion caused the activation of cyclic GMP-AMP synthase stimulator of interferon gene pathway due to cytoplasmic accumulation of damage-associated double-stranded DNA, inducing immunogenicity and enhancing the sensitivity of drug-resistant cells to chemotherapy. These findings suggest TREX1 upregulation may partially contribute to the survival of resistant cells, and its inhibition may represent a promising therapeutic strategy to enhance antitumor immunity and potentiate the efficacy of chemotherapy and/or immunotherapy in chemoresistant SCLCs. Significance: In this study, we show that targeting TREX1 induces an innate immune response and resensitizes SCLC cells to chemotherapy, representing a promising novel target for "immunologically" cold tumors, such as SCLC.

Trilaciclib use in extensive-stage small cell lung cancer (ES-SCLC): are clinical benefits seen in the real-world setting?

BACKGROUND: Trilaciclib, in comparison to placebo plus carboplatin, etoposide, ± atezolizumab (PEA), has shown significant reductions in incidence of severe neutropenia (SN) among patients with extensive-stage small cell lung cancer (ES-SCLC). Despite these findings, real-world utility remains limited. METHODS: A single-center quasi-experimental study compared trilaciclib + PEA (PEAT) versus PEA in ES-SCLC patients. The study period ranged from April 1, 2021 to July 31, 2022, for the PEAT recipients and February 1, 2020, to February 28, 2021, for PEA recipients. The primary endpoint evaluated was incidence of SN after cycle 1 and during the treatment period. Secondary endpoints included measures related to myelopreservation and patient outcomes. RESULTS: Among 34 PEAT and 44 PEA patients, baseline characteristics were similar, except for a higher median age (69 vs 64 years) and more males (64.7% vs 38.6%) in the PEAT cohort. The PEAT cohort exhibited a lower SN rate (3%) versus the PEA cohort (18%), with statistical significance demonstrated on multivariate analysis (p = 0.015). Additionally, the PEAT cohort also demonstrated significant reductions in red blood cell transfusion requirements (3% vs 23%; p = 0.02), grade 3-4 anemia (6% vs 25%; p = 0.03), and grade 3-4 thrombocytopenia (0% vs 11%, p = 0.045). CONCLUSION: Trilaciclib, in combination with PEA, demonstrated an improvement in the safety profile without compromising survival outcomes in ES-SCLC patients. These findings underscore the potential benefits of incorporating trilaciclib in real-world clinical settings for enhanced patient care.

DB-1314, a novel DLL3-targeting ADC with DNA topoisomerase I inhibitor, exhibits promising safety profile and therapeutic efficacy in preclinical small cell lung cancer models.

BACKGROUND: Delta-like ligand 3 (DLL3) is highly expressed on the cell surface of small cell lung cancer (SCLC), one of the most lethal malignancies, but minimally or not in normal tissues, making it an attractive target for SCLC. However, none of the DLL3-targeting antibody-drug conjugates (ADCs) have been approved for SCLC therapy yet. We developed DB-1314, the new anti-DLL3 ADC composed of a novel humanized anti-DLL3 monoclonal antibody (DB131401) conjugated with eight molecules of P1021 (topoisomerase I inhibitor), and described its preclinical profiles. METHODS: The binding epitope for DB131401 and Rovalpituzumab was tested by biolayer interferometry. The binding affinity and specificity of DB-1314 to DLL3 and other homologous proteins were respectively measured by surface plasmon resonance and enzyme-linked immunosorbent assay. Internalization, bystander effects, and antibody-dependent cell-mediated cytotoxicity (ADCC) were assessed by respective assay. DLL3 was quantified by antibodies bound per cell assay and immunohistochemistry. In vitro and in vivo growth inhibition studies were evaluated in SCLC cell lines, and cell line/patient-derived xenograft models. The safety profile was measured in cynomolgus monkeys. RESULTS: DB-1314 induces potent, durable, and dose-dependent antitumor effects in cells in vitro and in cell/patient-derived xenograft models in vivo. The killing activity of DB-1314 mechanically arises from P1021-induced DNA damage, whereby P1021 is delivered and released within tumor cells through DLL3-specific binding and efficient internalization. Bystander effects and ADCC also contribute to the antitumor activity of DB-1314. DB-1314 displays favorable pharmacokinetic and toxicokinetic profiles in rats and cynomolgus monkeys; besides, DB-1314 is well-tolerated at a dose of up to 60 mg/kg in monkeys. CONCLUSIONS: These results suggest that DB-1314 may be a candidate ADC targeting DLL3 for the treatment of DLL3-positive SCLC, supporting further evaluation in the clinical setting.

Efficacy and safety of G-CSF prophylaxis in patients with extensive-stage small cell lung cancer receiving chemoimmunotherapy.

OBJECTIVES: We aimed to evaluate the efficacy and safety of granulocyte-colony stimulating factor (G-CSF) prophylaxis during chemoimmunotherapy with carboplatin plus etoposide and atezolizumab in extensive-stage small cell lung cancer (ES-SCLC). METHODS: This retrospective, multicenter study enrolled ES-SCLC patients receiving carboplatin plus etoposide and atezolizumab, categorized into G-CSF and non-G-CSF groups. Demographic and disease-related data were collected. Response rates, progression-free survival (PFS), overall survival (OS), and toxicity were analyzed. RESULTS: Of 119 patients (median age: 63 years), the overall response rate (ORR) and disease control rate (DCR) were 72.3% and 81.5%, respectively. In the G-CSF group, the ORR was 76.4% compared to 60.0% in the non-G-CSF group (p = 0.33), and the DCR was 85.4% versus 70.0%, respectively (p = 0.46). Median PFS was 8.3 months (95% CI, 6.8-9.8) in the G-CSF group and 6.8 months (95% CI, 6.2-7.5) in the non-G-CSF group (p = 0.24). Median OS was 13.8 months (95% CI, 9.6-18.1) for the G-CSF group and 10.6 months (95% CI, 7.9-13.3) for the non-G-CSF group (p = 0.47). Grade 3 ≥ adverse events were similar between groups (49.4% vs. 33.3%, respectively, p = 0.12). CONCLUSION: G-CSF prophylaxis can be safely used in ES-SCLC patients undergoing carboplatin plus etoposide and atezolizumab regimen without significantly altering efficacy or increasing toxicity.

The Vasopressin Receptor Antagonist Tolvaptan Counteracts Tumor Growth in a Murine Xenograft Model of Small Cell Lung Cancer.

We have previously demonstrated that the vasopressin type 2 receptor (AVPR2) antagonist tolvaptan reduces cell proliferation and invasion and triggers apoptosis in different human cancer cell lines. To study this effect in vivo, a xenograft model of small cell lung cancer was developed in Fox1nu/nu nude mice through the subcutaneous inoculation of H69 cells, which express AVPR2. One group of mice (n = 5) was treated with tolvaptan for 60 days, whereas one group (n = 5) served as the control. A reduced growth was observed in the tolvaptan group in which the mean tumor volume was significantly smaller on day 60 compared to the control group. In the latter group, a significantly lower survival was observed. The analysis of excised tumors revealed that tolvaptan effectively inhibited the cAMP/PKA and PI3K/AKT signaling pathways. The expression of the proliferative marker proliferating cell nuclear antigen (PCNA) was significantly lower in tumors excised from tolvaptan-treated mice, whereas the expression levels of the apoptotic marker caspase-3 were higher than those in control animals. Furthermore, tumor vascularization was significantly lower in the tolvaptan group. Overall, these findings suggest that tolvaptan counteracts tumor progression in vivo and, if confirmed, might indicate a possible role of this molecule as an adjuvant in anticancer strategies.