Lurbinectedin in small cell lung cancer

Diverse pharmacological activities of β-carbolines: Substitution patterns, SARs and mechanisms of action

β-Carbolines, a class of indole-containing heterocyclic alkaloids, are widely distributed in nature and possess diverse bioactivities, making them promising drug candidates against a wide range of diseases. The remarkable medicinal potential of β-carbolines has spurred the pharmaceutical research community to study their derivatives extensively. This review updates the development of β-carboline derivatives in recent years (2015-2024), particularly with a focus on their anticancer, antiparasitic, antimicrobial, antiviral, and neuroprotective properties, based on the modification approaches such as substitution on indole N (ring B), pyridine or its reduced forms (ring C), and dimerization of β-carbolines. Moreover, the mechanisms of action and structure-activity relationships of these β-carboline derivatives are highlighted to offer valuable insights on the design and development of new β-carbolines with better pharmacological activities.

Proceedings of the 1st biannual bridging the gaps in lung cancer conference

Lung cancer is the leading cause of cancer death in the US and globally. The mortality from lung cancer has been declining, due to a reduction in incidence and advances in treatment. Although recent success in developing targeted and immunotherapies for lung cancer has benefitted patients, it has also expanded the complexity of potential treatment options for health care providers. To aid in reducing such complexity, experts in oncology convened a conference (Bridging the Gaps in Lung Cancer) to identify current knowledge gaps and controversies in the diagnosis, treatment, and outcomes of various lung cancer scenarios, as described here. Such scenarios relate to biomarkers and testing in lung cancer, small cell lung cancer, EGFR mutations and targeted therapy in non-small cell lung cancer (NSCLC), early-stage NSCLC, KRAS/BRAF/MET and other genomic alterations in NSCLC, and immunotherapy in advanced NSCLC.

Lurbinectedin is an effective alternative to platinum rechallenge and may restore platinum sensitivity in patients with sensitive relapsed small cell lung cancer

INTRODUCTION

Platinum rechallenge is recommended for patients with small cell lung cancer (SCLC) who relapse ≥90 days after completing first-line chemotherapy, although it may not always be the most suitable option.

AREAS COVERED

Articles for review were identified via PubMed and ClinicalTrials.gov searches, supplemented with non-indexed publications (e.g. conference abstracts) known to the manufacturer. We examined evidence for platinum re-exposure in patients with sensitive relapsed SCLC, and present lurbinectedin as a potential alternative. The complementary mechanisms of action of lurbinectedin and platinum, owing to opposite sensitivity of SCLC cells, may resensitize tumor cells to platinum. As efficacy outcomes with lurbinectedin are equivalent or better than those with platinum rechallenge and its hematological safety profile is more favorable, achieving maximum dose intensity is more likely. The simpler dosing schedule of lurbinectedin (1 vs 3 days) and lack of need for granulocyte colony-stimulating factor primary prophylaxis lessens treatment burden.

EXPERT OPINION

Incorporation of lurbinectedin into therapeutic algorithms for relapsed SCLC has challenged long-established treatment paradigms. Initial evidence indicates that using lurbinectedin after failure of first-line platinum may prolong the platinum-free interval and reserve platinum for later use. Current evidence supports lurbinectedin as a second-line option in patients with sensitive relapsed SCLC.

Auranofin inhibition of thioredoxin reductase sensitizes lung neuroendocrine tumor cells (NETs) and small cell lung cancer (SCLC) cells to sorafenib as well as inhibiting SCLC xenograft growth

Thioredoxin Reductase (TrxR) functions to recycle thioredoxin (Trx) during hydroperoxide metabolism mediated by peroxiredoxins and is currently being targeted using the FDA-approved anti-rheumatic drug, auranofin (AF), to selectively sensitize cancer cells to therapy. AF treatment decreased TrxR activity and clonogenic survival in small cell lung cancer (SCLC) cell lines (DMS273 and DMS53) as well as the H727 atypical lung carcinoid cell line. AF treatment also significantly sensitized DMS273 and H727 cell lines in vitro to sorafenib, an FDA-approved multi-kinase inhibitor that depleted intracellular glutathione (GSH). The pharmacokinetic, pharmacodynamic, and safety profile of AF was examined in nude mice with DMS273 xenografts administered AF intraperitoneally at 2 mg/kg or 4 mg/kg (IP) once (QD) or twice daily (BID) for 1-5 d. Plasma levels of AF were 10-20 μM (determined by mass spectrometry of gold), and the optimal inhibition of TrxR activity was obtained at 4 mg/kg once daily, with no effect on glutathione peroxidase 1 activity. This AF treatment extended for 14 d, inhibited TrxR (>75%), and resulted in a significant prolongation of median overall survival from 19 to 23 d (p = .04, N = 30 controls, 28 AF). In this experiment, there were no observed changes in animal bodyweight, complete blood counts (CBCs), bone marrow toxicity, blood urea nitrogen, or creatinine. These results support the hypothesis that AF effectively inhibits TrxR both in vitro and in vivo in SCLC, sensitizes NETs and SCLC to sorafenib, and could be repurposed as an adjuvant therapy with targeted agents that induce disruptions in thiol metabolism.

Sarmentosin alleviates doxorubicin-induced cardiotoxicity and ferroptosis via the p62-Keap1-Nrf2 pathway

Doxorubicin (Dox) is extensively used as an antitumor agent, but its severe cardiotoxicity significantly limits its clinical use. Current treatments for Dox-induced cardiotoxicity are inadequate, necessitating alternative solutions. This study evaluated the effects of sarmentosin, a compound from Sedum sarmentosum, on Dox-induced cardiotoxicity and dysfunction. Sarmentosin was administered as a pretreatment to both mice and H9c2 cells before Dox exposure. Subsequently, markers of Dox-induced cardiotoxicity and ferroptosis in serum and cell supernatants were measured. Western blot analysis was utilized to detect levels of ferroptosis, oxidative stress, and autophagy proteins. Additionally, echocardiography, hematoxylin-eosin staining, ROS detection, and immunofluorescence techniques were employed to support our findings. Results demonstrated that sarmentosin significantly inhibited iron accumulation, lipid peroxidation, and oxidative stress, thereby reducing Dox-induced ferroptosis and cardiotoxicity in C57BL/6 mice and H9c2 cells. The mechanism involved the activation of autophagy and the Nrf2 signaling pathway. These findings suggest that sarmentosin may prevent Dox-induced cardiotoxicity by mitigating ferroptosis. The study underscores the potential of compounds like sarmentosin in treating Dox-induced cardiotoxicity.

Efficacy and safety of sintilimab in combination with chemotherapy for recurrent extensive-stage small cell lung cancer: a real-world retrospective study

Background

Immune checkpoint inhibitors (ICIs) no longer are approved for second-line or later treatment of extensive-stage small cell lung cancer (ES-SCLC), and have not been studied in combination with chemotherapy. Exploring the efficacy and safety of second-line or later immunotherapy for ES-SCLC is an urgent clinical question that needs to be addressed, and combination therapies are an important research direction. This study intended to investigate the efficacy and safety of the sintilimab in combination with chemotherapy as a second-line and beyond treatment option for ES-SCLC.

Methods

Medical records of patients who received treatment with sintilimab in combination with chemotherapy or chemotherapy alone as a second-line or beyond therapy were retrospectively analyzed. The study evaluated efficacy and safety. Indicators of efficacy included objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS). Safety indicators included adverse events (AEs).

Results

This cohort comprised of 46 patients: 24 in the sintilimab combination chemotherapy group and 22 in the chemotherapy group. Chemotherapy received by both groups was either albumin-bound paclitaxel or irinotecan. Compared with the chemotherapy group, the sintilimab combination chemotherapy group had higher ORR and DCR (ORR: 37.5% vs. 9.1%, P=0.04; DCR: 75.0% vs. 40.9%, P=0.04), and significantly prolonged PFS and OS [median PFS (mPFS): 5.07 vs. 2.45 months, P=0.006; median OS (mOS): 14.43 vs. 10.34 months, P=0.009]. Also, there was no significant increase in the incidence of AEs in the sintilimab combination chemotherapy group, which was well tolerated by patients.

Conclusions

Sintilimab in combination with chemotherapy is superior to single-agent chemotherapeutic treatment as second-line or later therapy in ES-SCLC patients who have not received prior immunotherapy. These results need to be confirmed in future clinical trials.

Indole-containing pharmaceuticals: targets, pharmacological activities, and SAR studies

Indole is a prestigious heterocyclic skeleton widely found in both naturally-occurring and biologically-active compounds. Pharmaceutical agents containing an indole skeleton in their framework possess a wide range of pharmacological properties, including antiviral, antitumor, analgesic, and other therapeutic activities, and many indole-containing drugs have been proven to have excellent pharmacokinetic and pharmacological effects. Over the past few decades, the FDA has approved over 40 indole-containing drugs for the treatment of various clinical conditions, and the development of indole-related drugs has attracted significant attention from medicinal chemists. This review aims to provide an overview of all the approved drugs that contain an indole nucleus, focusing on their targets, pharmacological activities, and SAR studies.

Semisynthesis of 5-O-ester derivatives of renieramycin T and their cytotoxicity against non-small-cell lung cancer cell lines

The semisynthesis of 5-O-ester derivatives of renieramycin T was accomplished through the photoredox reaction of renieramycin M (1), a bistetrahydroisoquinolinequinone alkaloid isolated from the Thai blue sponge Xestospongia sp. This process led to the conversion of compound 1 to renieramycin T (2), which was subsequently subjected to Steglich esterification with appropriate acylating agents containing linear alkyl, N-tert-butoxycarbonyl-L-amino, and heterocyclic aromatic substituent. Notably, the one-pot transformation, combining the photoredox reaction and esterification led to the formation of 7-O-ester derivatives of renieramycin S due to hydrolysis. Subsequently, the in vitro cytotoxicity of the 17 semisynthesized derivatives against human non-small-cell lung cancer (NSCLC) cells in parallel with normal cell lines was evaluated. Among the tested compounds, 5-O-(3-propanoyl) ester of renieramycin T (3b) exhibited potent cytotoxic activity with half-maximal inhibitory concentration (IC50) values at 33.44 and 33.88 nM against H292 and H460 cell lines, respectively. These values were within the same range as compound 1 (IC50 = 34.43 and 35.63 nM) and displayed twofold higher cytotoxicity compared to compound 2 (IC50 = 72.85 and 83.95 nM). The steric characteristics and aromatic orientation of the 5-O-ester substituents played significant roles in their cytotoxicity. Notably, derivative 3b induced apoptosis with minimal necrosis, in contrast to the parental compound 1. Hence, the relationship between the structure and cytotoxicity of renieramycin-ecteinascidin hybrid alkaloids was investigated. This study emphasizes the potential of the series of 5-O-ester derivatives of renieramycin T as promising leads for the further development of potential anti-NSCLC agents.

Treatment and survival of patients with small cell lung cancer and brain metastasis

PURPOSE

To elucidate treatment patterns and their outcomes in patients with small cell lung cancer (SCLC) and brain metastasis (BM).

METHODS

In this retrospective study, patients with SCLC and BM were stratified by treatment modality into three groups: those treated with systemic therapy only, those treated with stereotactic radiosurgery (SRS) and systemic therapy, and those treated with whole-brain radiotherapy (WBRT) and systemic therapy. The primary outcomes were overall survival (OS) and time to central nervous system progression (TTCP).

RESULTS

The analysis included 149 patients. After BM diagnosis, 48 patients (32.2%) received systemic therapy alone, 33 received SRS with systemic therapy, and 68 received WBRT with systemic therapy. The median OS and TTCP were 7.2 months and 8.7 months, respectively. Patients receiving WBRT with systemic therapy exhibited better intracranial control, but not better OS, than did the other patients. Key prognostic factors affecting OS were age, BM lesion count, chemotherapy, and immunotherapy. Notably, the Eastern Cooperative Oncology Group performance status and BM lesion count significantly influenced intracranial control in patients treated with SRS and systemic therapy.

CONCLUSION

Although WBRT combined with systemic therapy offer better intracranial control in patients with SCLC and BM, this approach is not superior to the other approaches in terms of OS benefits. Emerging systemic therapies, such as immunotherapy, may be used as alternative or adjunctive treatments for specific patient populations. Further studies are warranted to refine treatment selection.

Remarkable response to PD-1 inhibitor in a patient with extensive-stage small cell lung cancer: a case report and literature review

We report a case of a 59-year-old male diagnosed with extensive-stage small cell lung cancer (SCLC). He received first-line platinum doublet chemotherapy and second-line topotecan-based regimen, but experienced disease progression after each line of therapy. He was then treated with Sintilimab, a PD-1 inhibitor, in combination with nab-paclitaxel in the third-line setting, which resulted in significant tumor shrinkage. Restaging scans showed a partial response per RECIST criteria with 62% reduction in tumor burden. This case highlights the application and efficacy of immune checkpoint inhibitors in extensive-stage SCLC.

Light-Mediated Transformation of Renieramycins and Semisynthesis of 4'-Pyridinecarbonyl-Substituted Renieramycin-Type Derivatives as Potential Cytotoxic Agents against Non-Small-Cell Lung Cancer Cells

The semisynthesis of renieramycin-type derivatives was achieved under mild and facile conditions by attaching a 1,3-dioxole-bridged phenolic moiety onto ring A of the renieramycin structure and adding a 4'-pyridinecarbonyl ester substituent at its C-5 or C-22 position. These were accomplished through a light-induced intramolecular photoredox reaction using blue light (4 W) and Steglich esterification, respectively. Renieramycin M (4), a bis-tetrahydroisoquinolinequinone compound isolated from the Thai blue sponge (Xestospongia sp.), served as the starting material. The cytotoxicity of the 10 natural and semisynthesized renieramycins against non-small-cell lung cancer (NSCLC) cell lines was evaluated. The 5-O-(4'-pyridinecarbonyl) renieramycin T (11) compound exhibited high cytotoxicity with half-maximal inhibitory concentration (IC₅₀) values of 35.27 ± 1.09 and 34.77 ± 2.19 nM against H290 and H460 cells, respectively. Notably, the potency of compound 11 was 2-fold more than that of renieramycin T (7) and equal to those of 4 and doxorubicin. Interestingly, the renieramycin-type derivatives with a hydroxyl group at C-5 and C-22 exhibited weak cytotoxicity. In silico molecular docking and dynamics studies confirmed that the mitogen-activated proteins, kinase 1 and 3 (MAPK1 and MAPK3), are suitable targets for 11. Thus, the structure-cytotoxicity study of renieramycins was extended to facilitate the development of potential anticancer agents for NSCLC cells.

Indirect treatment comparison of lurbinectedin versus other second-line treatments for small-cell lung cancer

Aim: Compare lurbinectedin versus other second-line (2L) small-cell lung cancer (SCLC) treatments. Methods: An unanchored matching-adjusted indirect comparison connected the platinum-sensitive SCLC cohort of a single-arm lurbinectedin trial to a network of three randomized controlled trials (oral and intravenous [IV] topotecan, and platinum re-challenge) identified by systematic literature review. Network meta-analysis methods estimated relative treatment effects. Results: In platinum-sensitive patients, lurbinectedin demonstrated a survival benefit and favorable safety profile versus oral and IV topotecan and platinum re-challenge (overall survival, hazard ratio [HR]: 0.43; 95% credible interval [CrI]: 0.27, 0.67; HR: 0.43; 95% CrI: 0.26, 0.70; HR: 0.42; 95% CrI: 0.30, 0.58 respectively). Conclusion: Lurbinectedin showed a robust survival benefit and favorable safety versus other SCLC treatments in 2L platinum-sensitive SCLC.

Current and Emerging Treatment Options for Patients With Relapsed Small-cell Lung Carcinoma: A Systematic Literature Review

Second-line treatment options are limited for patients with small-cell lung cancer (SCLC). We conducted a PRISMA-standard systematic literature review to evaluate the treatment landscape for patients with relapsed SCLC (PROSPERO number: CRD42022299759). Systematic searches of MEDLINE, Embase, and Cochrane Library were performed (October 2022) to identify publications (prior 5 years) from prospective studies of therapies for relapsed SCLC. Publications were screened against predetermined eligibility criteria; data were extracted to standardized fields. Publication quality was assessed using GRADE. The data were analyzed descriptively, grouped by drug class. Overall, 77 publications involving 6349 patients were included. Studies of tyrosine kinase inhibitors (TKIs) with established cancer indications accounted for 24 publications; topoisomerase I inhibitors for 15; checkpoint inhibitors (CPIs) for 11, and alkylating agents for 9 publications. The remaining 18 publications featured chemotherapies, small-molecule inhibitors, investigational TKIs and monoclonal antibodies, and a cancer vaccine. According to GRADE assessment, 69% of the publications reported low-/very-low-quality evidence; quality limitations included lack of randomization and small sample sizes. Only 6 publications/6 trials reported phase 3 data; 5 publications/2 trials reported phase 2/3 results. Overall, the clinical potential of alkylating agents and CPIs remained unclear; investigations of combination approaches and biomarker-directed usage are warranted. Phase 2 data from TKI trials were consistently promising; no phase 3 data were available. Phase 2 data for a liposomal formulation of irinotecan were promising. We confirmed an absence of promising investigational drug/regimens in late-stage development; thus, relapsed SCLC remains an area of high unmet need.