Topotecan versus cyclophosphamide, doxorubicin, and vincristine for the treatment of recurrent small-cell lung cancer

Biomarkers in the management of lung cancer: changing the practice of thoracic oncology

Lung cancer currently represents a leading cause of cancer death. Substantial progress achieved in the medical therapy of lung cancer during the last decade has been associated with the advent of targeted therapy, including immunotherapy. The targeted therapy has gradually shifted from drugs suppressing general mechanisms of tumor growth and progression to agents aiming at transforming mechanisms like driver mutations in a particular tumor. Knowledge of the molecular characteristics of a tumor has become an essential component of the more targeted therapeutic approach. There are specific challenges for biomarker determination in lung cancer, in particular a commonly limited size of tumor sample. Liquid biopsy is therefore of particular importance in the management of lung cancer. Laboratory medicine is an indispensable part of multidisciplinary management of lung cancer. Clinical Chemistry and Laboratory Medicine (CCLM) has played and will continue playing a major role in updating and spreading the knowledge in the field.

KC-180-2 Exerts Anti-SCLC Effects via Dual Inhibition of Tubulin Polymerization and Src Signaling

In this study, a series of N-benzyl-2-(5-phenylpyridin-2-yl) acetamide-based derivatives were successfully designed and synthesized as anti-cancer agents. KC-180-2 was screened as a potentially leading compound with dual mechanisms of action: Src signaling and tubulin polymerization inhibition. It efficiently suppressed the proliferation of five cancer cell lines (MDA-MB-231, H446, SKOV-3, HepG2, and HT29), with IC₅₀ values ranging from 5 to 188 nM, especially small-cell lung cancer (SCLC) cells (IC₅₀, 5 nM). Correspondingly, it exerted a significant therapeutic effect on the H446 small-cell lung cancer xenograft model, significantly reducing the volume of tumors without obvious toxicity. Mechanistically, this compound significantly inhibited the polymerization of purified tubulin in vitro, inducing G2/M cell cycle arrest and binding to the kinase catalytic domain of the Src protein, which reduced the phosphorylation of Src. Thus, KC-180-2 is a potential lead compound for the further development of a new anti-tumor drug against SCLC.

Feasibility and safety of platinum-doublet therapy in patients with small-cell lung cancer in the third-line setting: A multi-institutional retrospective study

Small-cell lung cancer (SCLC) is a highly malignant tumor, and no standard third-line therapy has been established. The present study retrospectively analyzed the efficacy and safety of platinum-based regimens in patients with third-line SCLC who received third-line chemotherapy. The association of regimen type with overall survival (OS) or time to treatment failure (TTF) was evaluated using the Cox hazard proportional method, including well-known covariates affecting the prognosis of SCLC. TTF and OS analyses were conducted using the Kaplan-Meier method. The data cutoff date was June 30, 2020. As a result, from January 2015 to August 2019, 111 patients were diagnosed with SCLC, and 37 received third-line chemotherapy. Subsequently, 15 patients received a platinum-doublet regimen, and 22 patients received a single-agent regimen. Only the type of regimen was significantly associated with TTF in univariate analysis (odds ratio, 0.44; 95% confidence interval, 0.20-0.95; P=0.03). There were no significant factors associated with OS. The median TTF of patients receiving a platinum-doublet regimen and those receiving a single-agent regimen were 3.9 and 2.3 months, respectively (P=0.03). The overall response rates of the platinum-doublet and single-agent regimens were 20.0 and 4.5%, respectively. Similarly, the disease control rates were 73.3 and 36.4% for platinum-doublet and single-agent regimens, respectively. There was a tendency for adverse events (AEs) with any grade to occur more often in platinum-based regimens compared with in single-agent regimens. Severe AEs of grade 3 or higher were observed more often in the platinum-based regimen, especially in myelosuppression. In conclusion, the present study demonstrated the feasibility and safety of platinum-doublet regimens in patients with SCLC in a third-line setting (Registration no. 2020-048. Date of registration, June 5, 2020).

Lurbinectedin in small cell lung cancer

Few treatment options are available for patients with small cell lung cancer (SCLC) in progression after a first-line therapy. A novel therapeutic approach is represented by lurbinectedin, a synthetic derivative of trabectedin that works by inhibiting oncogenic transcription and promoting apoptosis in tumor cells. A phase II basket trial demonstrated the activity of lurbinectedin at the dose of 3.2 mg/m2 in patients with SCLC who had failed a previous chemotherapy, with a response rate of 35.2%, a median progression-free survival (mPFS) of 3.5 months, and a median overall survival (mOS) of 9.3 months. Common severe adverse events (grades 3-4) were hematological disorders, including anemia (9%), leukopenia (29%), neutropenia (46%), and thrombocytopenia (7%). On the basis of the positive results of this phase II study, on June 2020, lurbinectedin was approved by the Food and Drug Administration as second line for SCLC patients in progression on or after platinum-based therapy. The subsequent phase III trial comparing the combination of lurbinectedin plus doxorubicin vs. CAV (cyclophosphamide, Adriamycin, and vincristine) or topotecan did not demonstrate an improvement in overall survival, although the experimental arm showed a superior safety profile. Combinations of lurbinectedin with other drugs, cytotoxic agents and immune checkpoint inhibitors, are currently under investigation. The results of these studies should better define the optimal clinical application of lurbinectedin.

Real-life second-line epirubicin-paclitaxel regimen as treatment of relapsed small-cell lung cancer: EpiTax study

BACKGROUND

Few therapeutic options are approved as second-line treatment after failure of platinum-based chemotherapy for patients with extensive-stage small-cell lung cancer (ES-SCLC). Topotecan widespread use remains challenged by the risk of severe toxicities in a pretreated population. Little is known about the efficacy and safety of epirubicin-paclitaxel doublet in second-line and beyond and especially cerebral outcomes.

METHODS

EpiTax is a retrospective multicenter observational real-life study. We evaluated the efficacy of epirubicin 90 mg/m² combined with paclitaxel 175 mg/m² every 3 weeks in SCLC patients after failure of at least one line of platinum-based chemotherapy. The primary endpoint was progression-free survival (PFS). Secondary endpoints were overall survival (OS), objective response rate (ORR), disease control rate (DCR), intracranial control rate (ICR), and safety.

RESULTS

A total of 29 patients were included. The median of previous systemic therapy lines was 2 (1-4). Eleven patients received the treatment in the second line. Characteristics of patients were a median age of 60 years (45-77), 65.5% of males with 72.4% of PS 0-1. Fifteen patients had a history of brain metastases. Median PFS and OS achieved 11.0 (95% CI, 8.1-16.3) and 23 (95% CI, 14.1-29.6) weeks, respectively. ORR was 34.5% and DCR was 55.2%. ICR was 3/15 (20%). Grade 3-4 adverse events were mainly hematological and concerned 7 patients. No case of febrile neutropenia or toxic death was reported.

CONCLUSION

Epirubicin-paclitaxel association highlighted promising efficacy with PFS and OS of 11 and 23 weeks, respectively, ORR of 34.5%, and a tolerable safety profile. This doublet could represent another valuable therapeutic option for ES-SCLC patients treated in the second line and beyond.

Toripalimab and anlotinib as a maintenance treatment for extensive-stage small-cell lung cancer: a case report

Small-cell lung cancer (SCLC) is characterized by rapid proliferation, high growth fraction and early locoregional and distant metastases. SCLC has been found to be significantly sensitive to platinum–etoposide chemotherapy, but most patients relapse within 6 months of completing initial treatment and median overall survival is about 10 months. Despite the current immunotherapy-treatment approach, median survival time and progression-free survival remain short. This case shows the potential efficacy of maintenance therapy with toripalimab and anlotinib after first-line platinum–etoposide chemotherapy in a patient with extensive-stage SCLC. The combination treatment prolonged the progression-free survival to approximately 13 months and overall survival to 25 months; this is well above the existing standard, and this patient did not experience any major adverse effects during the course of therapy.

New perspectives in the management of small cell lung cancer

The treatment of small cell lung cancer (SCLC) is a challenge for all specialists involved. New treatments have been added to the therapeutic armamentarium in recent months, but efforts must continue to improve both survival and quality of life. Advances in surgery and radiotherapy have resulted in prolonged survival times and fewer complications, while more careful patient selection has led to increased staging accuracy. Developments in the field of systemic therapy have resulted in changes to clinical guidelines and the management of patients with advanced disease, mainly with the introduction of immunotherapy. In this article, we describe recent improvements in the management of patients with SCLC, review current treatments, and discuss future lines of research.

Treatment of drug-induced immune thrombocytopenias

Several therapeutic agents can cause thrombocytopenia by either immune-mediated or non-immune-mediated mechanisms. Non-immune-mediated thrombocytopenia is due to direct toxicity of drug molecules to platelets or megakaryocytes. Immune-mediated thrombocytopenia, on the other hand, involves the formation of antibodies that react to platelet-specific glycoprotein complexes, as in classic drug-induced immune thrombocytopenia (DITP), or to platelet factor 4, as in heparin-induced thrombocytopenia (HIT) and vaccine-induced immune thrombotic thrombocytopenia (VITT). Clinical signs include a rapid drop in platelet count, bleeding or thrombosis. Since the patient's condition can deteriorate rapidly, prompt diagnosis and management are critical. However, the necessary diagnostic tests are only available in specialized laboratories. Therefore, the most demanding step in treatment is to identify the agent responsible for thrombocytopenia, which often proves difficult because many patients are taking multiple medications and have comorbidities that can themselves also cause thrombocytopenia. While DITP is commonly associated with an increased risk of bleeding, HIT and VITT have a high mortality rate due to the high incidence of thromboembolic complications. A structured approach to drug-associated thrombocytopenia/thrombosis can lead to successful treatment and a lower mortality rate. In addition to describing the treatment of DITP, HIT, VITT, and vaccine-associated immune thrombocytopenia, this review also provides the pathophysiological and clinical information necessary for correct patient management.

Repurposing of anti-lung cancer drugs as multi-target inhibitors of SARS-CoV-2 proteins: An insight from molecular docking and MD-simulation study

Herein we have selected seventeen anti-lung cancer drugs to screen against Mpro, PLpro and spike glycoproteins of SARS-CoV-2to ascertain the potential therapeutic agent against COVID-19. ADMET profiling were employed to evaluate their pharmacokinetic properties. Molecular docking studies revealed that Capmatinib (CAP) showed highest binding affinity against the selected proteins of SARS-CoV-2. Molecular Dynamics (MD) simulation and the analysis of RMSD, RMSF, and binding energy confirmed the abrupt conformational changes of the proteins due to the presence of this drug. These findings provide an opportunity for doing advanced experimental research to evaluate the potential drug to combat COVID-19.

Treatment of chemotherapy-induced thrombocytopenia in patients with non-hematologic malignancies

Chemotherapy-induced thrombocytopenia (CIT) is a common complication of the treatment of non-hematologic malignancies. Many patient-related variables (e.g., age, tumor type, number of prior chemotherapy cycles, amount of bone marrow tumor involvement) determine the extent of CIT. CIT is related to the type and dose of chemotherapy, with regimens containing gemcitabine, platinum, or temozolomide producing it most commonly. Bleeding and the need for platelet transfusions in CIT are rather uncommon except in patients with platelet counts below 25x10⁹/L in whom bleeding rates increase significantly and platelet transfusions are the only treatment. Nonetheless, platelet counts below 70x10⁹/L present a challenge. In patients with such counts, it is important to exclude other causes of thrombocytopenia (medications, infection, thrombotic microangiopathy, post-transfusion purpura, coagulopathy and immune thrombocytopenia). If these are not present, the common approach is to reduce chemotherapy dose intensity or switch to other agents. Unfortunately decreasing relative dose intensity is associated with reduced tumor response and remission rates. Thrombopoietic growth factors (recombinant human thrombopoietin, pegylated human megakaryocyte growth and development factor, romiplostim, eltrombopag, avatrombopag and hetrombopag) improve pretreatment and nadir platelet counts, reduce the need for platelet transfusions, and enable chemotherapy dose intensity to be maintained. National Comprehensive Cancer Network guidelines permit their use but their widespread adoption awaits adequate phase III randomized, placebo-controlled studies demonstrating maintenance of relative dose intensity, reduction of platelet transfusions and bleeding, and possibly improved survival. Their potential appropriate use also depends on consensus by the oncology community as to what constitutes an appropriate pretreatment platelet count as well as identification of patient-related and treatment variables that might predict bleeding.

Oncological Treatment-Related Fatigue in Oncogeriatrics: A Scoping Review

Fatigue is a highly prevalent symptom in both cancer patients and the older population, and it contributes to quality-of-life impairment. Cancer treatment-related fatigue should thus be included in the risk/benefit assessment when introducing any treatment, but tools are lacking to a priori estimate such risk. This scoping review was designed to report the current evidence regarding the frequency of fatigue for the different treatment regimens proposed for the main cancer indications, with a specific focus on age-specific data, for the following tumors: breast, ovary, prostate, urothelium, colon, lung and lymphoma. Fatigue was most frequently reported using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) versions 3 to 5. A total of 324 regimens were analyzed; data on fatigue were available for 217 (67%) of them, and data specific to older patients were available for 35 (11%) of them; recent pivotal trials have generally reported more fatigue grades than older studies, illustrating increasing concern over time. This scoping review presents an easy-to-understand summary that is expected to provide helpful information for shared decisions with patients regarding the anticipation and prevention of fatigue during each cancer treatment.

SCLC Treatment in the Immuno-Oncology Era: Current Evidence and Unmet Needs

Small cell lung cancer (SCLC) represents about 13%-15% of all lung cancers. It has a particularly unfavorable prognosis and in about 70% of cases occurs in the advanced stage (extended disease). Three phase III studies tested the combination of immunotherapy (atezolizumab, durvalumab with or without tremelimumab, and pembrolizumab) with double platinum chemotherapy, with practice-changing results. However, despite the high tumor mutational load and the chronic pro-inflammatory state induced by prolonged exposure to cigarette smoke, the benefit observed with immunotherapy is very modest and most patients experience disease recurrence. Unfortunately, biological, clinical, or molecular factors that can predict this risk have not yet been identified. Thanks to these clinically meaningful steps forward, SCLC is no longer considered an "orphan" disease. Innovative treatment strategies and combinations are currently under investigation to further improve the expected prognosis of patients with SCLC. Following the recent therapeutic innovations, we have reviewed the available literature data about SCLC management, with a focus on current unmet needs and potential predictive factors. In detail, the role of radiotherapy; fragile populations, such as elderly or low-performance status patients (ECOG PS 2), usually excluded from randomized studies; predictive factors of response useful to optimize and guide therapeutic choices; and new molecular targets and future combinations have been explored and revised.

Carboplatin plus nab-paclitaxel for recurrent small cell lung cancer: A phase II study

Background

We conducted a phase II study of carboplatin plus nab‐paclitaxel for the treatment of small cell lung cancer (SCLC) after the failure of a prior standard chemotherapy containing platinum, etoposide, irinotecan, and amrubicin if indicated. Patients with interstitial pneumonia complications were included in the study.

Methods

Patients received 100 mg/m² of nab‐paclitaxel weekly (on days 1, 8, and 15) and an AUC 5 of carboplatin on day 1. The study treatment was repeated every 3 weeks until disease progression or the appearance of unacceptable toxicities. The primary endpoint was the objective response rate.

Results

A total of 21 patients were enrolled, all of whom were eligible for inclusion in the analysis. Twelve patients had pre‐existing interstitial pneumonia. The overall response rate was 19.0% (90% confidence interval [CI]: 6.8%–38.4%). The lower limit of the 90% CI for the response rate did not exceed the prespecified threshold value of 10%. Among the 12 patients with pre‐existing interstitial pneumonia, the response rate was 25%. The median progression‐free survival time was 2.5 months (95% CI: 1.5–3.4 months), and the median survival time was 5.1 months (95% CI: 2.1–8.1 months). Two patients developed interstitial lung disease; both of these patients had pre‐existing interstitial pneumonia. One of the patients died from interstitial lung disease.

Conclusion

Combination chemotherapy with carboplatin plus nab‐paclitaxel for recurrent SCLC had a modest activity, although the primary study endpoint was not met. Further investigation of this regimen for patients with recurrent SCLC and interstitial pneumonia is warranted.

Immunotherapy in Small Cell Lung Cancer Treatment: a Promising Headway for Future Perspective

OPINION STATEMENT

Despite advancements in clinical research, both prognosis and treatment for SCLC patients are still in the nascent stage. SCLC is a fatal disease with high tumor mutational burden and is strongly associated with exposure to tobacco. This leads to the development of potential neo-antigens, inhibition of immune responses, and development of paraneoplastic disorders. Surgery, radiation, and chemotherapy are widely accepted treatments for cancer globally, and most recently, immunotherapy has now become the "fourth pillar" of SCLC treatment. Various immune checkpoint pathways regulate the activation of T cells at multiple stages during an immune response. T cell checkpoint inhibitors such as anti-PD1 (pembrolizumab, nivolumab), anti-PDL1, and anti-CTLA-4 (tremelimumab, ipilimumab) have potential to show anti-cancer activity along with the promise to prolong survival in patients with SCLC. Treatment with the CTLA-4-specific antibodies can restore the immune response by increasing the accumulation and survival of T-cells whereas monoclonal antibodies block either PD-1 or its ligands that prevent downregulation of effector T-cell, which enables the T-cells to mediate the death of tumor cells. Furthermore, monoclonal antibody in combination with chemotherapy has attained quite a focus to enhance the survival of SCLC patients. Apart from this, various immunotherapeutic approaches have been evaluated in the clinical trials for SCLC patients such as TLR9 agonist, anti-CD47, anti-ganglioside therapy, and anti-Notch signaling. The current review focuses on the rationale as well as on the clinical studies of immunotherapy in SCLC along with the clinical end results of certain immunotherapeutic agents and novel therapeutic combinations in SCLC patients.

RESILIENT part 1: A phase 2 dose-exploration and dose-expansion study of second-line liposomal irinotecan in adults with small cell lung cancer

BACKGROUND

RESILIENT (NCT03088813) is a phase 2/3 study assessing the safety, tolerability, and efficacy of liposomal irinotecan monotherapy in patients with small cell lung cancer and disease progression on/after first-line platinum-based therapy. Here, we present results from RESILIENT part 1.

METHODS

This open-label, single-arm, safety run-in evaluation with dose-exploration and dose-expansion phases included patients ≥18 years old with Eastern Cooperative Oncology Group performance status of 0/1; those with asymptomatic central nervous system metastases were eligible. The primary objectives were to evaluate safety and tolerability and recommend a dose for further development. Efficacy end points were objective response rate (ORR), progression-free survival (PFS), and overall survival (OS).

RESULTS

During dose exploration, 5 patients received intravenous liposomal irinotecan at 85 mg/m² (deemed not tolerable; dose-limiting toxicity) and 12 patients received 70 mg/m² (deemed tolerable). During dose expansion, 13 additional patients received intravenous liposomal irinotecan at 70 mg/m² . Of these 25 patients (median age [range], 59.0 [48.0-73.0] years, 92.0% with metastatic disease), 10 experienced grade ≥3 treatment-related treatment-emergent adverse events (TEAEs), most commonly diarrhea (20.0%) and neutropenia (16.0%), and 3 had serious treatment-related TEAEs, of whom 2 died. ORR was 44.0% (95% confidence interval [CI]: 24.40-65.07; 1 complete response, 10 partial responses) and median (95% CI) PFS and OS were 3.98 (1.45-4.24) months and 8.08 (5.16-9.82) months, respectively.

CONCLUSION

Overall, no new safety signals were identified with liposomal irinotecan, and antitumor activity was promising. RESILIENT part 2, a randomized, controlled, phase 3 study of liposomal irinotecan versus topotecan, is ongoing.

LAY SUMMARY

Small cell lung cancer (SCLC) is an aggressive disease with few treatment options after platinum-based therapy. Administering 1 option, irinotecan, as a "liposomal" formulation, may extend drug exposure and improve outcomes. The RESILIENT part 1 trial assessed the safety and efficacy of liposomal irinotecan in 25 adults with SCLC after disease progression despite platinum-based therapy. No new safety concerns were reported. The most common moderate-to-severe side effects were diarrhea (20% of patients) and neutropenia (16%). Tumors responded to treatment in 44% of patients. Average survival was 8.08 months, and time to disease progression was 3.98 months. Liposomal irinotecan trials are ongoing.

Extensive-Stage Small-Cell Lung Cancer: First-Line and Second-Line Treatment Options

Extensive-stage small-cell lung cancer is a therapeutically challenging disease. After more than two decades without clinical progress, the addition of programmed cell death protein 1 axis blockade to platinum-based chemotherapy has demonstrated sustained overall survival benefit and represents the current standard of care in the first-line setting. Despite this benefit, resistance emerges relatively rapidly in virtually all patients. Although newer treatments are being incorporated in the relapse setting, marked therapeutic resistance is typically observed in patients with relapsed small-cell lung cancer (SCLC), underscoring the need of developing more effective therapies in this setting. Notably, recent progress in the understanding of the molecular biology of SCLC might bring possibilities toward molecularly informed therapeutic strategies for patients with SCLC, which could have a significant impact for improving outcomes in this disease. Here, we review current treatment options and recent progress made in the first-line and relapsed SCLC, including the role of biomarkers and new evolving therapeutic strategies.

Therapeutic Modalities in Small Cell Lung Cancer: a paradigm shift after decades of quiescence

INTRODUCTION

Small cell lung cancer (SCLC) is known to be the most aggressive of all thoracic malignancies, notoriously known for its very poor prognosis. Platinum based chemotherapy has been the standard of care for decades. Despite years of research, no treatment novelties with significant impact on survival have been achieved until recently. The last few years have witnessed light at the end of the tunnel with immunotherapy proving to improve survival. Nevertheless, responses were not homogeneous in all subgroups, and finding who would best benefit from treatment remains unanswered. Multiple limitations exist, and the quest for optimal biomarkers seemed unfruitful until the discovery of different SCLC phenotypes.

AREAS COVERED

In this review, the authors briefly discuss SCLC phenotypes and biomarker assays. Then, the authors continue with the main trials of SCLC treatment using chemotherapy, immunotherapy and targeted treatment in the front-line or subsequent line settings.

EXPERT OPINION

Research has been extensively implemented to better understand the biology of SCLC, and test for the optimal use of immunotherapy in patients with SCLC, as well as to enhance responses via possible combinations. Targeted mechanisms of action have also been attempted; yet no solid proof of efficacy has been established.

Weekly nanoparticle albumin-bound paclitaxel and paclitaxel for relapsed small cell lung cancer: A retrospective observational study

In addition to advanced non-small cell lung cancer, nanoparticle albumin-bound paclitaxel (nab-PTX) may also harbor potential benefit for patients with relapsed small cell lung cancer (SCLC), since weekly paclitaxel (PTX) shows modest activity for relapsed SCLC. We evaluated the efficacy and safety of both weekly nab-PTX and PTX for relapsed SCLC.We retrospectively reviewed 52 consecutive relapsed SCLC patients who were treated with weekly nab-PTX or PTX at our hospital.The response rate, median progression-free survival and overall survival with nab-PTX and PTX were 5.6 vs 8.8%, 3.2 vs 1.7 months, and 5.4 vs 4.5 months, respectively. No statistically significant differences were observed. There was no statistical difference between the 2 groups for ≥Grade 3 adverse events.Weekly nab-PTX and PTX showed similar activity for relapsed SCLC. The toxicity profile of nab-PTX was equally tolerable to that of PTX.

Real-world burden of chemotherapy-induced myelosuppression in patients with small cell lung cancer: a retrospective analysis of electronic medical data from community cancer care providers

AIMS

Chemotherapy-induced myelosuppression, which commonly exhibits as neutropenia, anemia, or thrombocytopenia, represents a substantial burden for patients with cancer that affects health-related quality of life and increases healthcare resource utilization (HCRU). We evaluated the burden of myelosuppression among chemotherapy-treated patients with small cell lung cancer (SCLC) using real-world data from community cancer care providers in the Western United States.

MATERIALS AND METHODS

This was a retrospective, observational analysis of electronic medical records (EMRs) from Providence St. Joseph Health hospital-associated oncology clinics between January 2016 and December 2019. Patient demographics were assessed from the date of first SCLC diagnosis in adult patients with chemotherapy-induced grade ≥3 myelosuppression in first-line (1L) or second-line-and-beyond (2L+) treatment settings. Myelosuppressive adverse events (AEs), treatment patterns, and HCRU were assessed from the date of chemotherapy initiation (index date) until 12 months, date of the last visit, date of death, or study end, whichever occurred earliest.

RESULTS

Of 347 eligible patients with SCLC who had received chemotherapy (mean age 66; 49% female), all had received at least 1L treatment, and 103 (29.7%) had a 2L + treatment recorded within the EMR during the study period. Of 338 evaluable patients with longitudinal laboratory data, 206 (60.9%) experienced grade ≥3 myelosuppressive AEs, most commonly neutropenia, anemia, and thrombocytopenia (44.9, 41.1, and 25.4 per 100 patients, respectively). Rates of granulocyte colony-stimulating factor use and red blood cell transfusions were 47.0 and 41.7 per 100 patients, respectively. There was a trend toward increasing the use of supportive care interventions and visits to inpatient and outpatient facilities in patients with myelosuppressive AEs in more than one cell lineage.

CONCLUSIONS

Chemotherapy-induced myelosuppression places a substantial real-world burden on patients with SCLC in the community cancer care setting. Innovations to protect bone marrow from chemotherapy-induced damage have the potential to reduce this burden.

Developments in systemic therapies for the management of lung cancer

Lung cancer accounts for approximately 1 in 10 new cancer diagnoses annually and is responsible for the most cancer-associated deaths in Australia. Despite such figures, there is reason for optimism with many practice-changing developments to report for the management of patients with thoracic malignancies over the last few years. We outline such changes, including the emerging role of immunotherapy in the neoadjuvant and adjuvant setting for patients with localised non-small-cell lung cancer, as well as the established standard of consolidation immunotherapy following definitive chemoradiotherapy for those with locally advanced disease. In the metastatic setting, combination chemotherapy-immunotherapy approaches have become the new paradigm for most patients in the absence of a recognised driver mutation. A range of novel targeted therapies now exist and are Pharmaceutical Benefits Scheme (PBS)-subsidised for targets such as EGFR, ALK and ROS1, with many others, such as KRAS G12C, NTRK, MET, RET and HER2, also with therapies rapidly being developed. Even among patients with small-cell lung cancer, who account for the worst prognoses and until recently have received a chemotherapy regimen that has remained unchanged in over 20 years, there is a new standard-of-care in combination chemotherapy-immunotherapy. Furthermore, immunotherapy and potentially anti-vascular endothelial growth factor agents now also play a role in mesothelioma treatment. Last, given recent developments in immunotherapy, targeted therapy and combination approaches in the non-small-cell lung cancer space, there is an increasing recognition of the diversity of lived experience for such patients and need for survivorship programmes to acknowledge such nuances.

Limited-Stage Small-Cell Lung Cancer: Current Progress and the Next Frontier

Limited-stage (LS) small-cell lung cancer (SCLC) is defined as disease confined to a tolerable radiation portal without extrathoracic metastases. Despite clinical research over two decades, the prognosis of LS-SCLC patients remains poor. The current standard of care for LS-SCLC patients is concurrent platinum-based chemotherapy with thoracic radiotherapy (RT). Widespread heterogeneity on the optimal radiation dose and fractionation regimen among physicians highlights the logistical challenges of administering BID regimens. Prophylactic cranial irradiation (PCI) is recommended to patients following a good initial response to chemoradiation due to improved overall survival from historical trials and the propensity for LS-SCLC to recur with brain metastases. However, PCI utilization is being debated due to the greater availability of magnetic resonance imaging (MRI) and data in extensive-stage SCLC regarding close MRI surveillance in lieu of PCI while spurring novel RT techniques, such as hippocampal-avoidance PCI. Additionally, novel treatment combinations incorporating targeted small molecule therapies and immunotherapies with or following radiation for LS-SCLC have seen recent interest and some concepts are being investigated in clinical trials. Here, we review the landscape of progress, limitations, and challenges for LS-SCLC including current standard of care, novel radiation techniques, and the integration of novel therapeutic strategies for LS-SCLC.

Small Cell Lung Cancer, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Small Cell Lung Cancer (SCLC) provide recommended management for patients with SCLC, including diagnosis, primary treatment, surveillance for relapse, and subsequent treatment. This selection for the journal focuses on metastatic (known as extensive-stage) SCLC, which is more common than limited-stage SCLC. Systemic therapy alone can palliate symptoms and prolong survival in most patients with extensive-stage disease. Smoking cessation counseling and intervention should be strongly promoted in patients with SCLC and other high-grade neuroendocrine carcinomas. The "Summary of the Guidelines Updates" section in the SCLC algorithm outlines the most recent revisions for the 2022 update, which are described in greater detail in this revised Discussion text.

Risk Factors for Infections, Antibiotic Therapy, and Its Impact on Cancer Therapy Outcomes for Patients with Solid Tumors

Infections represent a significant cause of morbidity and mortality in cancer patients. Multiple factors related to the patient, tumor, and cancer therapy can affect the risk of infection in patients with solid tumors. A thorough understanding of such factors can aid in the identification of patients with substantial risk of infection, allowing medical practitioners to tailor therapy and apply prophylactic measures to avoid serious complications. The use of novel treatment modalities, including targeted therapy and immunotherapy, brings diagnostic and therapeutic challenges into the management of infections in cancer patients. A growing body of evidence suggests that antibiotic therapy can modulate both toxicity and antitumor response induced by chemotherapy, radiotherapy, and especially immunotherapy. This article provides a comprehensive review of potential risk factors for infections and therapeutic approaches for the most prevalent infections in patients with solid tumors, and discusses the potential effect of antibiotic therapy on toxicity and efficacy of cancer therapy.

Irinotecan monotherapy as third- or further-line treatment for patients with small cell lung cancer

BACKGROUND

Small cell lung cancer (SCLC) is a very aggressive cancer and recurrence is inevitable. Treatment of recurrent disease is important for improving the prognosis of patients with SCLC.

METHODS

We conducted a retrospective observational study to investigate the efficacy and safety of irinotecan monotherapy as third- or further-line treatment in patients with SCLC.

RESULTS

Data of 15 patients who had received irinotecan monotherapy as third- or further-line treatment between 2004 and 2019 were analyzed. The median progression-free survival duration (95% confidence interval) from the initiation of treatment with irinotecan was 2.7 (1.4-3.8) months, and the median overall survival duration (95% confidence interval) from the initiation of irinotecan treatment was 10.0 (3.9-12.9) months. Partial response, stable disease or non-complete response/non-progressive disease, and progressive disease were observed in 1, 6, and 8 patients, respectively. Adverse events ⩾ grade 3 in severity were observed in 2/2 (100%) patients who were homozygous for UGT1A1 mutation, 2/3 (66.7%) patients who were heterozygous for UGT1A1 mutation, 4/6 (66.7%) patients who had wild-type UGT1A1, and 2/4 (50.0%) patients in whom the UGT1A1 mutation status was unknown.

CONCLUSION

Our results suggest that irinotecan monotherapy can be a useful alternative treatment option in the third-line setting for patients with SCLC.

Update 2021: Management of Small Cell Lung Cancer

BACKGROUND

Accounting for 14% of lung cancer, small cell lung cancer (SCLC) is a highly aggressive neuroendocrine malignancy with rapid proliferation, early spread, and poor survival.

AIM AND METHODS

We provide an overview of recent advances regarding SCLC pathogenesis, subtypes, and treatment development through literature review of key trials.

RESULTS

There are no validated biomarkers or approved targeted treatments for this overly heterogeneous disease, but recent analyses have identified some promising targets and four major subtypes which may carry unique therapeutic vulnerabilities in SCLC. Treatment wise, only a third of patients present with limited stage SCLC, which can be managed with a combined modality approach with curative intent (usually chemo-radiotherapy, but in some eligible patients, surgery followed by systemic treatment). For advanced or extensive stage SCLC, combined chemotherapy (platinum-etoposide) and immunotherapy (atezolizumab or durvalumab during and after chemotherapy) has become the new standard front-line treatment, with modest improvement in overall survival. In the second-line setting, for disease relapse ≤ 6 months, topotecan, lurbinectedin, and clinical trials are reasonable treatment options; for disease relapse > 6 months, original regimen, topotecan or lurbinectedin can be considered. Moreover, Trilaciclib, a CD4/CD6 inhibitor, was recently FDA-approved to decrease the incidence of chemotherapy-related myelosuppression in SCLC patients.

CONCLUSIONS

While modest improvements in survival have been made especially in the metastatic setting with chemo-immunotherapy, further research in understanding the biology of SCLC is warranted to develop biomarker-driven therapeutic strategies and combinational approaches for this aggressive disease.

Integrated exposure-response analysis of efficacy and safety of lurbinectedin to support the dose regimen in small-cell lung cancer

Purpose

These exposure–response (E–R) analyses integrated lurbinectedin effects on key efficacy and safety variables in relapsed SCLC to determine the adequacy of the dose regimen of 3.2 mg/m² 1-h intravenous infusion every 3 weeks (q3wk).

Methods

Logistic models and Cox regression analyses were applied to correlate lurbinectedin exposure metrics (AUC_tot and AUC_u) with efficacy and safety endpoints: objective response rate (ORR) and overall survival (OS) in SCLC patients (n = 99) treated in study B-005 with 3.2 mg/m² q3wk, and incidence of grade 4 (G4) neutropenia and grade 3–4 (G ≥ 3) thrombocytopenia in a pool of cancer patients from single-agent phase I to III studies (n = 692) treated at a wide range of doses. A clinical utility index was used to assess the appropriateness of the selected dose.

Results

Effect of lurbinectedin AUC_u on ORR best fitted to a sigmoid-maximal response (E_max) logistic model, where E_max was dependent on chemotherapy-free interval (CTFI). Cox regression analysis with OS found relationships with both CTFI and AUC_u. An E_max logistic model for G4 neutropenia and a linear logistic model for G ≥ 3 thrombocytopenia, which retained platelets and albumin at baseline and body surface area, best fitted to AUC_tot and AUC_u. AUC_u between approximately 1000 and 1700 ng·h/L provided the best benefit/risk ratio, and the dose of 3.2 mg/m² provided median AUC_u of 1400 ng·h/L, thus maximizing the proportion of patients within that lurbinectedin target exposure range.

Conclusions

The relationships evidenced in this integrated E–R analysis support a favorable benefit-risk profile for lurbinectedin 3.2 mg/m² q3wk.

Trial registration

Clinicaltrials.gov: NCT02454972; registered May 27, 2015.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00280-021-04366-3.

Advances in Treatment of Recurrent Small Cell Lung Cancer (SCLC): Insights for Optimizing Patient Outcomes from an Expert Roundtable Discussion

Second-line treatment options for patients with relapsed, extensive-stage small cell lung cancer (ES-SCLC) are limited, and even with currently available treatments, prognosis remains poor. Until recently, topotecan (a topoisomerase I inhibitor) was the only drug approved by the United States (US) Food and Drug Administration (FDA) for the management of ES-SCLC following progression after first-line treatment with etoposide plus a platinum derivative (EP; carboplatin preferred). With the most recent approval of EP plus a programmed death ligand 1 (PD-L1) inhibitor, there are now more therapeutic options for managing ES-SCLC. A number of novel agents have emerging data for activity in relapsed ES-SCLC, and single-agent lurbinectedin (an alkylating drug and selective inhibitor of oncogenic transcription and DNA repair machinery in tumor cells) has conditional FDA approval for use in this patient population. Trilaciclib, a short-acting cyclin-dependent kinase 4/6 (CDK 4/6) inhibitor, has also been recently approved as a supportive intervention for use prior to an EP or a topotecan-containing regimen to diminish the incidence of chemotherapy-induced myelosuppression. The current review is based on a recent expert roundtable discussion and summarizes current therapeutic agents and emerging data on newer agents and biomarkers. It also provides evidence-based clinical considerations and a treatment decision tool for oncologists treating patients with relapsed ES-SCLC. This paper discusses the importance of various factors to consider when selecting a second-line treatment option, including prior first-line treatment, available second-line treatment options, tumor platinum sensitivity, and patient characteristics (such as performance status, comorbidities, and patient-expressed and perceived values).

Temozolomide in Grade 3 Gastroenteropancreatic Neuroendocrine Neoplasms: A Multicenter Retrospective Review

BACKGROUND

Grade 3 gastroenteropancreatic neuroendocrine neoplasms (G3 GEPNENs) are often aggressive, and the optimal treatment is unclear for this subgroup of neuroendocrine neoplasms (NENs). Temozolomide (TEM)-based regimens have been increasingly used to treat grade 1-2 NENs, but their efficacy in G3 NENs remains undetermined. We aimed to assess the clinical efficacy of TEM-containing regimens in advanced grade 3 GEPNENs.

MATERIALS AND METHODS

A multicenter retrospective review (2008-2018) of patients with metastatic/unresectable G3 GEPNENs who received a TEM-containing regimen was undertaken within a North American partnership to pool data. The primary endpoint was time to treatment failure (TTF). Radiologic response was extracted from local reports.

RESULTS

One hundred and thirty patients in six high-volume NEN centers were included (median age 55, 64% male, 18% functional, 67% pancreatic NEN). Forty-nine percent were well-differentiated, 35% poorly differentiated, and 15% unknown based on local pathology reports. The regimen used was capecitabine and temozolomide (CAPTEM) in 92% and TEM alone in 8%. Radiological response by local assessment was seen in 36% of patients. Median TTF was 3.6 months and median overall survival (OS) 19.2 months. Six percent of patients required discontinuation of therapy due to adverse events. TTF was longer in first-line treatment (7.8 months vs. 2.9 months; hazard ratio, 1.62; 95% confidence interval, 1.11-2.36; p = .015) and in patients with pancreatic NENs (panNENs) compared with gastrointestinal NENs (5.8 months vs 1.8 months; p = .04). The overall response rate was higher in the first-line setting (51% vs 29%; p = .02) and in panNEN (41% vs 23%; p = .04).

CONCLUSION

This is the largest TEM treatment series in G3 NEN, involving collaboration of several major North American NEN centers as a partnership. Thirty-six percent of patients showed some degree of radiographic response, and treatment was generally well tolerated, although the median duration of response was short. Response rates and time to treatment failure were superior in the first-line setting. CAPTEM should be considered a viable treatment option in this setting. Further randomized trials are warranted.

IMPLICATIONS FOR PRACTICE

Neuroendocrine neoplasms (NENs) are heterogeneous, and optimal treatment for aggressive grade 3 (G3) NENs remains undetermined. The capecitabine and temozolomide (CAPTEM) regimen has been used in low-grade pancreas NENs but there are few data for its safety and efficacy in the G3 setting. This article reports on the efficacy of temozolomide-containing regimens, particularly CAPTEM, in management of G3 NENs. The good tolerance and response rate show that CAPTEM should be considered a viable regimen in treatment of G3 NENs pending confirmatory prospective studies.

Evaluation of topotecan monotherapy for relapsed small-cell lung cancer after amrubicin monotherapy failure

Objective: The utility of topotecan monotherapy for relapsed small-cell lung cancer (SCLC) after failure of amrubicin monotherapy has not been evaluated. We aimed to investigate the efficacy and safety of topotecan monotherapy in patients with relapsed SCLC after amrubicin monotherapy.

Patients and Methods: We retrospectively analyzed data from 16 patients with relapsed SCLC who were treated with topotecan monotherapy after amrubicin monotherapy at our hospital.

Results: The response rate, progression-free survival, and overall survival were 0%, 32.5 days (95% confidence interval [CI] = 18–51), and 112 days (95% CI = 55–267), respectively. The most common adverse events (grade ≥3) were leukopenia (31.3%) and thrombocytopenia (31.3%), followed by anemia, anorexia, edema, and lung infections.

Conclusion: The efficacy of topotecan monotherapy for relapsed SCLC after amrubicin monotherapy is inconclusive. Therefore, further studies are warranted.

Genomic and Transcriptomic Characterization of Relapsed SCLC Through Rapid Research Autopsy

Introduction

Relapsed SCLC is characterized by therapeutic resistance and high mortality rate. Despite decades of research, mechanisms responsible for therapeutic resistance have remained elusive owing to limited tissues available for molecular studies. Thus, an unmet need remains for molecular characterization of relapsed SCLC to facilitate development of effective therapies.

Methods

We performed whole-exome and transcriptome sequencing of metastatic tumor samples procured from research autopsies of five patients with relapsed SCLC. We implemented bioinformatics tools to infer subclonal phylogeny and identify recurrent genomic alterations. We implemented immune cell signature and single-sample gene set enrichment analyses on tumor and normal transcriptome data from autopsy and additional primary and relapsed SCLC data sets. Furthermore, we evaluated T cell-inflamed gene expression profiles in neuroendocrine (ASCL1, NEUROD1) and non-neuroendocrine (YAP1, POU2F3) SCLC subtypes.

Results

Exome sequencing revealed clonal heterogeneity (intertumor and intratumor) arising from branched evolution and identified resistance-associated truncal and subclonal alterations in relapsed SCLC. Transcriptome analyses further revealed a noninflamed phenotype in neuroendocrine SCLC subtypes (ASCL1, NEUROD1) associated with decreased expression of genes involved in adaptive antitumor immunity whereas non-neuroendocrine subtypes (YAP1, POU2F3) revealed a more inflamed phenotype.

Conclusions

Our results reveal substantial tumor heterogeneity and complex clonal evolution in relapsed SCLC. Furthermore, we report that neuroendocrine SCLC subtypes are immunologically cold, thus explaining decreased responsiveness to immune checkpoint blockade. These results suggest that the mechanisms of innate and acquired therapeutic resistances are subtype-specific in SCLC and highlight the need for continued investigation to bolster therapy selection and development for this cancer.

Current Strategies for Extensive Stage Small Cell Lung Cancer Beyond First-line Therapy

Extensive stage small cell lung cancer carries extremely poor prognosis and adding immune checkpoint inhibitor to platinum etoposide combination in first line only improved outcomes modestly. Once disease recurs, treatment response is only transient in nature. Various strategies that are being explored include dual checkpoint blockade, BiTE and CAR-T cell approaches. Immune checkpoint inhibitors are being combined with PARP inhibitors. Other approaches currently being investigated include liposomal irinotecan and combining known active agents for SCLC in relapsed setting such as newly approved lurbinectedin with doxorubicin, paclitaxel, irinotecan or topotecan with ATR inhibitor (Berzosertib). Temozolomide has also been tested in combination with a Parp inhibitor. New antibody or small molecule drug conjugates are being actively investigated, so is a biomarker based approach. Better understanding of small cell lung cancer disease biology via high through-put genomic, proteomic and methylation profiling offer glimpse of hope in our efforts to contain this deadly disease. A table of representative molecular targets under investigation is provided in the end.

Topotecan or other agents as second-line therapy for relapsed small-cell lung cancer: A meta-analysis of randomized studies

Small cell lung cancer (SCLC) is exceptionally responsive to chemotherapy and radiotherapy. In relapsed patients, particularly in resistant/refractory cases, the progression of disease occurs rapidly with second-line agents. Topotecan (TOPO), a camptothecin analog, is the only agent able to increase overall survival (OS) compared with the best supportive care alone. However, the efficacy of platinum-based chemotherapy rechallenge or other agents has not been systematically explored. In the present review, published articles, which evaluated outcome and toxicity associated with TOPO or non-TOPO-based chemotherapy in patients with SCLC from inception to September 2020 were systematically searched and identified by searching the PubMed, EMBASE and Cochrane Library databases. The primary outcome of interest was the risk of death (OS), and the secondary endpoints were risk of progression progression-free survival (PFS), overall response rate (ORR) and G3-4 hematological toxicities. A total of nine studies were included in quantitative synthesis for a total of 1,689 patients. They included platinum-based rechallenge, anthracycline-based combinations or camptothecin analogs. TOPO did not improve OS with respect to other therapies [hazard ratio (HR), 0.92; 95% confidence interval (95% CI), 0.78-1.09; P=0.33]. Similarly, PFS was similar in the two arms (HR, 1.1; 95% CI, 0.72-1.67; P=0.66). The ORR was not statistically higher with non-TOPO agents (relative risk, 1.53; 95% CI, 0.95-2.48). In subgroup analysis, combination chemotherapy was associated with an improved PFS but not OS or ORR compared with TOPO alone (HR, 1.85; 95% CI, 1.52-2.24; P<0.01). The rates of G3-4 anemia, febrile neutropenia and neutropenia were similar. In conclusion, in patients with relapsed SCLC, TOPO was associated with a similar survival, PFS and ORR as other agents. However, polychemotherapy was associated with improved PFS.

Efficacy and Safety of Rovalpituzumab Tesirine Compared With Topotecan as Second-Line Therapy in DLL3-High SCLC: Results From the Phase 3 TAHOE Study

INTRODUCTION

DLL3, an atypical Notch ligand, is expressed in SCLC tumors but is not detectable in normal adult tissues. Rovalpituzumab tesirine (Rova-T) is an antibody-drug conjugate containing a DLL3-targeting antibody tethered to a cytotoxic agent pyrrolobenzodiazepine by means of a protease-cleavable linker. The efficacy and safety of Rova-T compared with topotecan as second-line therapy in patients with SCLC expressing high levels of DLL3 (DLL3-high) was evaluated.

METHODS

The TAHOE study was an open-label, two-to-one randomized, phase 3 study comparing Rova-T with topotecan as second-line therapy in DLL3-high advanced or metastatic SCLC. Rova-T (0.3 mg/kg) was administered intravenously on day 1 of a 42-day cycle for two cycles, with two additional cycles available to patients who met protocol-defined criteria for continued dosing. Topotecan (1.5 mg/m2) was administered intravenously on days 1 to 5 of a 21-day cycle. The primary end point was overall survival (OS).

RESULTS

Patients randomized to Rova-T (n = 296) and topotecan (n = 148) were included in the efficacy analyses. The median age was 64 years, and 77% had the extensive disease at initial diagnosis. The median OS (95% confidence interval) was 6.3 months (5.6-7.3) in the Rova-T arm and 8.6 months (7.7-10.1) in the topotecan arm (hazard ratio, 1.46 [95% confidence interval: 1.17-1.82]). An independent data monitoring committee recommended that enrollment be discontinued because of the shorter OS observed with Rova-T compared with topotecan. Safety profiles for both drugs were consistent with previous reports.

CONCLUSIONS

Compared with topotecan, which is the current standard second-line chemotherapy, Rova-T exhibited an inferior OS and higher rates of serosal effusions, photosensitivity reaction, and peripheral edema in patients with SCLC. A considerable unmet therapeutic need remains in this population.

Lung cancer

Lung cancer is one of the most frequently diagnosed cancers and the leading cause of cancer-related deaths worldwide with an estimated 2 million new cases and 1·76 million deaths per year. Substantial improvements in our understanding of disease biology, application of predictive biomarkers, and refinements in treatment have led to remarkable progress in the past two decades and transformed outcomes for many patients. This seminar provides an overview of advances in the screening, diagnosis, and treatment of non-small-cell lung cancer and small-cell lung cancer, with a particular focus on targeted therapies and immune checkpoint inhibitors.

Cost-Effectiveness Analysis of Durvalumab Plus Chemotherapy in the First-Line Treatment of Extensive-Stage Small Cell Lung Cancer

BACKGROUND

In the CASPIAN trial, durvalumab + chemotherapy demonstrated significant improvements in overall survival compared with chemotherapy alone in patients with extensive-stage small cell lung cancer (SCLC). We aimed to assess the cost-effectiveness of durvalumab in patients with extensive-stage SCLC from the US healthcare system perspective.

PATIENTS AND METHODS

A comprehensive Markov model was adapted to evaluate cost and effectiveness of durvalumab combination versus platinum/etoposide alone in the first-line therapy of extensive-stage SCLC based on data from the CASPIAN study. The main endpoints included total costs, life years (LYs), quality-adjusted life-years (QALYs), and incremental cost-e-ectiveness ratios (ICERs). Model robustness was assessed with sensitivity analysis, and additional subgroup analyses were also performed.

RESULTS

Durvalumab + chemotherapy therapy resulted in an additional 0.27 LYs and 0.20 QALYs, resulting in an ICER of $464,711.90 per QALY versus the chemotherapy treatment. The cost of durvalumab has the greatest influence on this model. Subgroup analyses showed that the ICER remained higher than $150,000/QALY (the willingness-to-pay threshold in the United States) across all patient subgroups.

CONCLUSIONS

Durvalumab in combination with platinum/etoposide is not a cost-effective option in the first-line treatment of patients with extensive-stage SCLC.

Alkylaminophenol and GPR17 Agonist for Glioblastoma Therapy: A Combinational Approach for Enhanced Cell Death Activity

Drug resistance and tumor heterogeneity limits the therapeutic efficacy in treating glioblastoma, an aggressive infiltrative type of brain tumor. GBM cells develops resistance against chemotherapeutic agent, temozolomide (TMZ), which leads to the failure in treatment strategies. This enduring challenge of GBM drug resistance could be rational by combinatorial targeted therapy. Here, we evaluated the combinatorial effect of phenolic compound (2-(3,4-dihydroquinolin-1(2H)-yl)(p-tolyl)methyl)phenol (THTMP), GPR17 agonist 2-({5-[3-(Morpholine-4-sulfonyl)phenyl]-4-[4-(trifluoromethoxy)phenyl]-4H-1,2,4-triazol-3-yl}sulfanyl)-N-[4-(propan-2-yl)phenyl]acetamide (T0510.3657 or T0) with the frontline drug, TMZ, on the inhibition of GBM cells. Mesenchymal cell lines derived from patients' tumors, MMK1 and JK2 were treated with the combination of THTMP + T0, THTMP + TMZ and T0 + TMZ. Cellular migration, invasion and clonogenicity assays were performed to check the migratory behavior and the ability to form colony of GBM cells. Mitochondrial membrane permeability (MMP) assay and intracellular calcium, [Ca2+]i, assay was done to comprehend the mechanism of apoptosis. Role of apoptosis-related signaling molecules was analyzed in the induction of programmed cell death. In vivo validation in the xenograft models further validates the preclinical efficacy of the combinatorial drug. GBM cells exert better synergistic effect when exposed to the cytotoxic concentration of THTMP + T0, than other combinations. It also inhibited tumor cell proliferation, migration, invasion, colony-forming ability and cell cycle progression in S phase, better than the other combinations. Moreover, the combination of THTMP + T0 profoundly increased the [Ca2+]i, reactive oxygen species in a time-dependent manner, thus affecting MMP and leading to apoptosis. The activation of intrinsic apoptotic pathway was regulated by the expression of Bcl-2, cleaved caspases-3, cytochrome c, HSP27, cIAP-1, cIAP-2, p53, and XIAP. The combinatorial drug showed promising anti-tumor efficacy in GBM xenograft model by reducing the tumor volume, suggesting it as an alternative drug to TMZ. Our findings indicate the coordinated administration of THTMP + T0 as an efficient therapy for inhibiting GBM cell proliferation.

Overcoming Chemotherapy Resistance in SCLC

SCLC is an aggressive form of lung cancer with a very poor prognosis. Although SCLC initially responds very well to platinum-based chemotherapy, it eventually recurs and at recurrence is nearly universally resistant to therapy. In light of the recent advances in understanding regarding the biology of SCLC, we review findings related to SCLC chemotherapy resistance. We discuss the potential clinical implications of recent preclinical discoveries in altered signaling pathways, transcriptional landscapes, metabolic vulnerabilities, and the tumor microenvironment.

Inhibition of topoisomerase I shapes antitumor immunity through the induction of monocyte-derived dendritic cells

Understanding the rationale of combining immunotherapy and other anticancer treatment modalities is of great interest because of interpatient variability in single-agent immunotherapy. Here, we demonstrated that topoisomerase I inhibitors, a class of chemotherapeutic drugs, can alter the tumor immune landscape, corroborating their antitumor effects combined with immunotherapy. We observed that topotecan-conditioned TC-1 tumors were occupied by a vast number of monocytic cells that highly express CD11c, CD64, and costimulatory molecules responsible for the favorable changes in the tumor microenvironment. Ly6C⁺MHC-II⁺CD11c^hiCD64^hi cells, referred to as topotecan-induced monocyte-derived dendritic cells (moDCs), proliferate and activate antigen-specific CD8⁺ T cells to levels equivalent to those of conventional DCs. Phenotypic changes in Ly6C⁺ cells towards moDCs were similarly induced by exposure to topotecan in vitro, which was more profoundly facilitated in the presence of tumor cells. Notably, anti-M-CSFR reversed the acquisition of DC-like properties of topotecan-induced moDCs, leading to the abolition of the antitumor effect of topotecan combined with a cancer vaccine. In short, topoisomerase I inhibitors generate monocyte-derived antigen-presenting cells in tumors, which could be mediated by M-CSF-M-CSFR signaling.

Screening and assessment of molecular mechanistic actions of 5-hydroxy-1-methylpiperidin-2-one against free radicals, lung cancer cell line (A549), and binding properties on bovine serum albumin

Background

Natural products play a key role in treating different ailment including diabetes, asthma, skin diseases, and cancer. It is well known that synthetic drugs elicit significant toxicity when used in the clinic. A higher drug affinity towards carrier protein Bovine Serum Albumin (BSA) would enhance a higher drug bioavailability which in turn leads to a higher therapeutic efficacy. The focus of the present study was to investigate antioxidant and anti-cancer potential of 5-hyrdoxy1-methylpiperidin-2-one (5-HMP) isolated from leaves of Tragia involucrata.

Methods and material

In vitro free radical scavenging assays and MTT assay were employed to assess the antioxidant activity of 5-HMP and cytotoxicity of 5-HMP on lung cancer cell line, A549, respectively. In addition, attempts were made to investigate 5-HMP binding capacity on BSA by spectral studies and molecular docking.

Results

The antioxidant data revealed that 5-HMP inhibited the radicals with an IC50 value of 49.55 ± 0.75 μg/ml which was comparable with the IC50 values afforded by l-ascorbic acid. 5-HMP exhibited a dose-dependent cytotoxicity on A549 cells with an IC50 value of 30.00 ± 0.55 μg/ml. further 5-HMP induced a cell cycle arrest in A549 at S and G2/M phase. The fluorescence quenching was observed when an increasing concentration of 5-HMP, reacts with a fixed concentration of BSA (1.0 μM). The fluorescence quenching of BSA by 5-HMP indicated a binding constant of K5-HMP = 2.8 ± 1.4 × 104M−1 with corresponding binding free energy (ΔG)−6.06 K.cal/mole.

Conclusions

This paper concluded that 5-HMP possesses antioxidant properties, cytotoxic effects and also it possesses good drug binding properties on bovine serum albumin.

Doxorubicin sensitizes cancer cells to Smac mimetic via synergistic activation of the CYLD/RIPK1/FADD/caspase-8-dependent apoptosis

Smac/Diablo is a pro-apoptotic protein via interaction with inhibitors of apoptosis proteins (IAPs) to relieve their inhibition of caspases. Smac mimetic compounds (also known as antagonists of IAPs) mimic the function of Smac/Diablo and sensitize cancer cells to TNF-induced apoptosis. However, the majority of cancer cells are resistant to Smac mimetic alone. Doxorubicin is a widely used chemotherapeutic drug and causes adverse effect of cardiotoxicity in many patients. Therefore, it is important to find strategies of combined chemotherapy to increase chemosensitivity and reduce the adverse effects. Here, we report that doxorubicin synergizes with Smac mimetic to trigger TNF-mediated apoptosis, which is mechanistically distinct from doxorubicin-induced cell death. Doxorubicin sensitizes cancer cells including human pancreatic and colorectal cancer cells to Smac mimetic treatment. The combined treatment leads to synergistic induction of TNFα to initiate apoptosis through activating NF-κB and c-Jun signaling pathways. Knockdown of caspase-8 or knockout of FADD significantly blocked apoptosis synergistically induced by Smac mimetic and doxorubicin, but had no effect on cell death caused by doxorubicin alone. Moreover, Smac mimetic and doxorubicin-induced apoptosis requires receptor-interacting protein kinase 1 (RIPK1) and its deubiquitinating enzyme cylindromatosis (CYLD), not A20. These in vitro findings demonstrate that combination of Smac mimetic and doxorubicin synergistically triggers apoptosis through the TNF/CYLD/RIPK1/FADD/caspase-8 signaling pathway. Importantly, the combined treatment induced in vivo synergistic anti-tumor effects in the xenograft tumor model. Thus, the combined therapy using Smac mimetic and doxorubicin presents a promising apoptosis-inducing strategy with great potential for the development of anti-cancer therapy.

Immunotherapy in small cell lung cancer: one step at a time: a narrative review

Chemotherapy with or without radiotherapy has been the standard of care for many years for patients with small cell lung cancer (SCLC). Despite exceptionally high responses (up to 80%) with chemotherapy, the majority of patients relapse rapidly within weeks to months after treatment completion. Therefore, new and better treatment options are necessary. Recently, synergistic activity has been reported for the addition of immune checkpoint inhibitors (ICI) to standard platinum-based chemotherapy in the therapeutic strategy of advanced SCLC. For the first time after several decades, a significant survival improvement was achieved for this population. However, the overwhelming majority of patients do not respond to ICI, or relapse rapidly. There is need for better knowledge about the biology, histopathologic features, and molecular pathways of SCLC. This can probably help to identify the optimal predictive biomarkers, which are warranted to develop an individual therapeutic strategy including the rational use of a combination of immunotherapeutic agents. Here, we provide an overview of the rationale for and clinical results of the completed and ongoing trials using different strategies of immunotherapy in SCLC. In addition, opportunities for further improvement of therapies will be discussed, including the addition of radiotherapy, co-stimulatory antibodies, and other immune modifying agents.

An overview of lurbinectedin as a new second-line treatment option for small cell lung cancer

Small cell lung cancer (SCLC) is a highly proliferative, aggressive form of lung cancer that carries a poor prognosis. Recent approvals with new therapeutic options represent the first in more than a decade for SCLC. Lurbinectedin, a newly approved second-line option, is a synthetic alkaloid that covalently binds DNA, generating double-strand breaks, and disrupts DNA-protein interactions and RNA transcription. Lurbinectedin may also modulate the tumor microenvironment by inducing apoptosis of peripheral blood monocytes and tumor associated macrophages, decreasing expression of the inflammatory chemokine (C-C motif) ligand 2 (CCL2) and reducing tumor angiogenesis. A single-arm, open-label, basket trial included 105 patients with SCLC that had received one prior line of therapy. Patients received lurbinectedin 3.2 mg/m² as an intravenous infusion every 3 weeks, resulting in a response rate of 35.2% and a disease control rate of 68.6%. The response rate was 45% among those with >90 days chemotherapy free interval (CTFI) and 22% in the resistant group (CTFI < 90 days). The median overall survival was 9.3 months. Myelosuppression is the most frequent clinically significant adverse event, particularly neutropenia; however, neutropenic fever occurred in only 5% of those in the SCLC cohort of the basket trial. Nausea and fatigue were also noted. The side effect profile compares favorably to topotecan, while a direct comparison of tolerability can be made between lurbinectedin versus topotecan or pegylated-liposomal doxorubicin from CORAIL, a randomized study for platinum-resistant/refractory ovarian cancer. A press release has reported the ongoing clinical trial for SCLC including combination lurbinectedin and doxorubicin versus topotecan or cyclophosphamide, doxorubicin, and vinblastine to be negative. The details may provide more insight at publication, and future trials will be important to further define the clinical utility of lurbinectedin. Lurbinectedin represents a new option in second-line SCLC.

TOP1 inhibition therapy protects against SARS-CoV-2-induced lethal inflammation

The ongoing pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is currently affecting millions of lives worldwide. Large retrospective studies indicate that an elevated level of inflammatory cytokines and pro-inflammatory factors are associated with both increased disease severity and mortality. Here, using multidimensional epigenetic, transcriptional, in vitro, and in vivo analyses, we report that topoisomerase 1 (TOP1) inhibition suppresses lethal inflammation induced by SARS-CoV-2. Therapeutic treatment with two doses of topotecan (TPT), an FDA-approved TOP1 inhibitor, suppresses infection-induced inflammation in hamsters. TPT treatment as late as 4 days post-infection reduces morbidity and rescues mortality in a transgenic mouse model. These results support the potential of TOP1 inhibition as an effective host-directed therapy against severe SARS-CoV-2 infection. TPT and its derivatives are inexpensive clinical-grade inhibitors available in most countries. Clinical trials are needed to evaluate the efficacy of repurposing TOP1 inhibitors for severe coronavirus disease 2019 (COVID-19) in humans.

A Phase II Trial of Prexasertib (LY2606368) in Patients With Extensive-Stage Small-Cell Lung Cancer

BACKGROUND

This study assessed the checkpoint kinase 1 inhibitor prexasertib in patients with extensive-stage small-cell lung cancer (ED-SCLC).

PATIENTS AND METHODS

This was a parallel-cohort phase II study of 105 mg/m² prexasertib once every 14 days for patients who progressed after no more than two prior therapies and had platinum-sensitive (Cohort 1) or platinum-resistant/platinum-refractory (Cohort 2) disease. The primary endpoint was objective response rate (ORR). Secondary endpoints included disease control rate (DCR), progression-free survival (PFS), overall survival (OS), safety, and pharmacokinetics. Exploratory endpoints included biomarker identification and assessment of an alternative regimen (Cohort 3: 40 mg/m² days 1-3, 14-day cycle).

RESULTS

In Cohort 1 (n = 58), ORR was 5.2%; DCR, 31%; median PFS, 1.41 months (95% confidence interval [CI], 1.31-1.64); and median OS, 5.42 months (95% CI, 3.75-8.51). In Cohort 2 (n = 60), ORR was 0%; DCR, 20%; median PFS, 1.36 months (95% CI, 1.25-1.45); and median OS, 3.15 months (95% CI, 2.27-5.52). The most frequent all-grade, related, treatment-emergent adverse events were decreased neutrophil count (Cohort 1, 69.6%; Cohort 2, 73.3%), decreased platelet count (Cohort 1, 51.8%; Cohort 2, 50.0%), decreased white blood cell count (Cohort 1, 28.6%; Cohort 2, 40.0%), and anemia (Cohort 1, 39.3%; Cohort 2, 28.3%). Eleven patients (19.6%) in Cohort 1 and one patient (1.7%) in Cohort 2 experienced grade ≥3 febrile neutropenia. Prexasertib pharmacokinetics were consistent with prior studies. Cohort 3 outcomes were similar to those of Cohorts 1 and 2. No actionable biomarkers were identified.

CONCLUSION

Prexasertib did not demonstrate activity to warrant future development as monotherapy in ED-SCLC.

Doxorubicin induces arterial stiffness: A comprehensive in vivo and ex vivo evaluation of vascular toxicity in mice

Arterial stiffness is an important predictor of cardiovascular risk. Clinical studies have demonstrated that arterial stiffness increases in cancer patients treated with the chemotherapeutic doxorubicin (DOX). However, the mechanisms of DOX-induced arterial stiffness remain largely unknown. This study aimed to evaluate artery stiffening in DOX-treated mice using in vivo and ex vivo techniques. Male C57BL/6J mice were treated for 2 weeks with 2 mg/kg (low dose) or 4 mg/kg (high dose) of DOX weekly. Arterial stiffness was assessed in vivo with ultrasound imaging (abdominal aorta pulse wave velocity (aaPWV)) and applanation tonometry (carotid-femoral PWV) combined with ex vivo vascular stiffness and reactivity evaluation. The high dose increased aaPWV, while cfPWV did not reach statistical significance. Phenylephrine (PE)-contracted aortic segments showed a higher Peterson's modulus (Ep) in the high dose group, while Ep did not differ when vascular smooth muscle cells (VSMCs) were relaxed by a NO donor (DEANO). In addition, aortic rings of DOX-treated mice showed increased PE contraction, decreased basal nitric oxide (NO) index and impaired acetylcholine-induced endothelium-dependent relaxation. DOX treatment contributed to endothelial cell loss and reduced endothelial nitric oxide synthase (eNOS) expression in the aorta. In conclusion, we have replicated DOX-induced arterial stiffness in a murine model and this aortic stiffness is driven by impaired endothelial function, contributing to increased vascular tone.

Therapeutic targeting of ATR yields durable regressions in small cell lung cancers with high replication stress

Small cell neuroendocrine cancers (SCNCs) are recalcitrant cancers arising from diverse primary sites that lack effective treatments. Using chemical genetic screens, we identified inhibition of ataxia telangiectasia and rad3 related (ATR), the primary activator of the replication stress response, and topoisomerase I (TOP1), nuclear enzyme that suppresses genomic instability, as synergistically cytotoxic in small cell lung cancer (SCLC). In a proof-of-concept study, we combined M6620 (berzosertib), first-in-class ATR inhibitor, and TOP1 inhibitor topotecan in patients with relapsed SCNCs. Objective response rate among patients with SCLC was 36% (9/25), achieving the primary efficacy endpoint. Durable tumor regressions were observed in patients with platinum-resistant SCNCs, typically fatal within weeks of recurrence. SCNCs with high neuroendocrine differentiation, characterized by enhanced replication stress, were more likely to respond. These findings highlight replication stress as a potentially transformative vulnerability of SCNCs, paving the way for rational patient selection in these cancers, now treated as a single disease.