Low-dose irinotecan as a second-line chemotherapy for recurrent small cell lung cancer

Topoisomerase I poisons-induced autophagy: Cytoprotective, Cytotoxic or Non-protective

Topoisomerase I inhibitors represent a widely used class of antineoplastic agents that promote both single-stranded and double-stranded breaks in the DNA of tumor cells, leading to tumor cell death. Topotecan and irinotecan are the clinically relevant derivatives of the parent drug, camptothecin. As is the case with many if not most anticancer agents, irinotecan and topotecan promote autophagy. However, whether the autophagy is cytotoxic, cytoprotective, or non-protective is not clearly defined, and may depend largely upon the genetic background of the tumor cell being investigated. This review explores the available literature regarding the nature of the autophagy induced by these clinically utilized topoisomerase I inhibitors in preclinical tumor models with the goal of determining whether the targeting of autophagy might have potential as a therapeutic strategy to enhance the antitumor response and/or overcome drug resistance.

A phase II study of antiangiogenic therapy (Apatinib) plus chemotherapy as second-line treatment in advanced small cell lung cancer

INTRODUCTION

Currently, only a few options are available for the treatment of patients with small-cell lung cancer (SCLC) after the failure of first-line platinum-based chemotherapy. The present study aimed to evaluate the efficacy and safety of apatinib plus chemotherapy for second-line treatment of advanced SCLC.

PATIENTS AND METHODS

This prospective clinical trial recruited patients treated with apatinib plus second-line chemotherapy until disease progression or intolerable toxicity. Logrank test power analysis was used for calculating samples. The primary endpoint was progression-free survival (PFS), and the secondary endpoints were objective response rate (ORR), disease control rate (DCR), overall survival (OS), and safety.

RESULTS

A total of 29/31 enrolled patients were available for response evaluation until October 2019. The ORR and DCR were 27.59% (8/29) and 96.55% (28/29), respectively. The median PFS and OS were 7.36 months and 14.16 months, respectively, indicating better efficacy compared with the standard second-line chemotherapies. The most common adverse events (AEs) were neutropenia (41.94%, 13/31), followed by leucopenia (35.48%, 11/31) and thrombocytopenia (25.81%, 8/31). The grade 3-4 AEs occurred in 12 (38.71%) patients, of which neutropenia (19.35%, 6/31), leucopenia (9.68%, 3/31), and proteinuria (6.45%, 2/31) were most common. Patients receiving an initial dose of apatinib 250 mg had a better tolerance.

CONCLUSION

Antiangiogenic therapy plus chemotherapy had encouraging efficacy in advanced SCLC patients, which provides an insight into the current status of second-line therapy in SCLC.

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.

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.

Real-world treatment patterns and outcomes in small-cell lung cancer: a systematic literature review

Background

Small-cell lung cancer (SCLC) accounts for 12-15% of lung cancers and is associated with poor survival outcomes and high symptom burden. This study employed a broad, systematic search strategy and timeframe to identify evidence on real-world treatment patterns and outcomes for SCLC outside the USA, including understanding sub-populations such as extensive-stage (ES) or limited-stage (LS) disease.

Methods

Databases (MEDLINE, Embase, and EBM reviews) were searched for journal articles published in the English language between 1 January 2000-1 March 2020 and supplemented by hand searching of conference abstracts and posters presented at conferences between 1 January 2016-1 March 2020 reporting real-world treatment outcomes in patients with SCLC. A targeted clinical guideline review was also completed.

Results

One-hundred studies provided quantitative data; 57 were available as full-text articles, whilst the remaining 43 were presented as abstracts or posters. The majority (80 studies, 80%) of included studies reported treatment in the first-line setting, where platinum-based chemotherapy and chemoradiotherapy was the most commonly used treatment strategy, in line with current treatment guidelines in SCLC. First-line treatments were found to have a high response rate; however, most patients relapsed early. No studies reported treatment or outcomes with immune-oncology therapies. Second-line treatment options were very limited, and primarily consisted of either re-treatment with first-line regimen or topotecan, but the prognosis for these patients remained poor. Outcomes were particularly poor amongst those with ES or relapsed disease vs. LS disease.

Conclusions

SCLC treatment patterns and short survival outcomes have remained constant over the previous 20 years. Due to the search timeframe, none of the studies identified reported on the impact of recently approved immune-oncology therapies in SCLC. Further data is needed on the impact of immunotherapies on treatment patterns and real-world outcomes in SCLC.

Phase II Trial of Carfilzomib Plus Irinotecan in Patients With Small-cell Lung Cancer Who Have Progressed on Prior Platinum-based Chemotherapy

INTRODUCTION

The purpose of this study was to evaluate the efficacy and tolerability of carfilzomib plus irinotecan (C/I) in patients with relapsed small-cell lung cancer (SCLC).

PATIENTS AND METHODS

Patients with SCLC who progressed after 1 platinum-containing regimen for recurrent or metastatic disease were eligible. Patients were stratified as: sensitive (SS) (progressive disease > 90 days after chemotherapy) or refractory (RS) (progressive disease 30 to 90 days after chemotherapy) and received up to 6 cycles of C/I; imaging was performed every 2 cycles. The primary endpoint was 6-month overall survival (OS).

RESULTS

All 62 patients enrolled were evaluable for efficacy and adverse events. 6-month OS was 59% in the platinum SS and 54% in the platinum RS. The overall response rate was 21.6% (2.7% complete response, 18.9% partial response) in SS (n = 37) and 12.5% (all partial response) in RS (n = 25). The disease control rate was 68% (SS) and 56% (RS). Progression-free survival and OS were 3.6 months (95% confidence interval [CI], 2.6-4.6 months) and 6.9 months (95% CI, 4.3-12.3 months) in SS, and 3.3 months (95% CI, 1.8-3.9 months) and 6.8 months (95% CI, 4.1-11 months) in RS. Twenty-nine (47%) patients experienced ≥ grade 3 adverse events; 8 (12.9%) subjects had grade 4 toxicities. Three treatment-related deaths occurred: myocardial infarction (possible), lung infection (possible), and sepsis (probable).

CONCLUSION

In patients with relapsed SCLC, C/I was effective in the treatment of SS and RS. With 4.8% grade 5 toxicity, C/I is a viable option for relapsed patients with SCLC with performance status 0 to 1, particularly in platinum-resistant patients, or subjects who cannot receive immunotherapy.

The Roles of Common Variation and Somatic Mutation in Cancer Pharmacogenomics

Cancer pharmacogenomics is the science concerned with understanding genetic alterations and its effects on the pharmacokinetics and pharmacodynamics of anti-cancer drugs, with the aim to provide cancer patients with the precise medication that will achieve a good response and cause low/no incidence of adverse events. Advances in biotechnology and bioinformatics have enabled genomic research to evolve from the evaluation of alterations at the single-gene level to studies on the whole-genome scale using large-scale genotyping and next generation sequencing techniques. International collaborative efforts have resulted in the construction of databases to curate the identified genetic alterations that are clinically significant, and these are currently utilized in clinical sequencing and liquid biopsy screening/monitoring. Furthermore, countless clinical studies have accumulated sufficient evidence to match cancer patients to therapies by utilizing the information of clinical-relevant alterations. In this review we summarize the importance of germline alterations that act as predictive biomarkers for drug-induced toxicity and drug response as well as somatic mutations in cancer cells that function as drug targets. The integration of genomics into the medical field has transformed the era of cancer therapy from one-size-fits-all to cancer precision medicine.

Managing Patients With Relapsed Small-Cell Lung Cancer

Despite high response rates to initial therapy, relapses are common in patients with small-cell lung cancer (SCLC). Systemic therapy after first-line failure remains important in the treatment paradigm of SCLC. Reinitiation of a previously administered first-line chemotherapy regimen is recommended for relapse > 6 months from completion of initial therapy. For relapse ≤ 6 months of initial therapy, sequential therapy with single agents is recommended. Clinical trial enrollment should be considered at all stages of treatment of SCLC. This review highlights the available treatment options in relapsed SCLC. In particular, we focus on prospective clinical trials demonstrating activity for the most commonly used agents in this setting. We end with a discussion on future directions and emerging targets with potential to improve outcomes in relapsed SCLC.

Activation of endoplasmic reticulum stress promotes autophagy and apoptosis and reverses chemoresistance of human small cell lung cancer cells by inhibiting the PI3K/AKT/mTOR signaling pathway

OBJECTIVE

This study aims to investigate the effects of endoplasmic reticulum stress (ERS) on autophagy, apoptosis and chemoresistance of human small cell lung cancer (SCLC) cells via the PI3K/AKT/mTOR signaling pathway.

RESULTS

The expressions of ERS-related proteins (PEAK, eIF2α and CHOP) up-regulated, autophagy-related proteins (LC3, LC3-II and Beclin1) and apoptosis-related proteins (Bax and procaspase-3) down-regulated in NCI-H446 and H69 cells after tunicamycin treatment for 24 h. Compared with the blank group, the tunicamycin, BEZ235 and tunicamycin + BEZ235 groups exhibited decreased expressions of p-PI3K, p-AKT and p-mTOR, and increased expressions of autophagy-related proteins (LC3, LC3-II and Beclin1) and apoptosis proteins (Bax and procaspase-3), and the most obvious changes were observed in the tunicamycin + BEZ235 group.

MATERIALS AND METHODS

CCK-8 assay was applied to select the best cell line from five SCLC cell lines (NCI-H446, H69, H526, H146 and H209). Finally, NCI-H446 and H69 cells were selected for further experiments. NCI-H446/CDDP and H69/CDDP were selected and divided into the blank group, tunicamycin (an ESR inducer) group, BEZ235 (inhibitors of PI3K/AKT/mTOR pathway) group and tunicamycin + BEZ235 group. Cell apoptosis was detected by flow cytometry. Autophagy was observed by fluorescence microscopy and flow cytometry. Western blotting was used to detect the expressions of ERS-related proteins, autophagy-related proteins, apoptosis-related proteins and PI3K/AKT/mTOR pathway-related proteins.

CONCLUSIONS

Our findings provide evidence that the activation of ERS could promote autophagy and apoptosis and reverse chemoresistance of human SCLC cells by inhibiting the PI3K/AKT/mTOR pathway.

Evaluating the Potential for Delivery of Irinotecan via the Buccal Route: Physicochemical Characterization and In Vitro Permeation Assessment Across Porcine Buccal Mucosa

Irinotecan (CPT-11) is used to treat advanced colorectal cancer as an intravenous therapy. Depending on pH, CPT-11 exists in either a lactone (active) or carboxylate (inactive) form, or both. In this investigation, the feasibility for systemic delivery of CPT-11 through the buccal route was evaluated. Permeation of CPT-11 across porcine buccal mucosa was studied in vitro using side-by-side flow through diffusion cells at 37°C. Experiments were performed over a pH range from 4 to 9, and the permeability of both the lactone and carboxylate forms of CPT-11 was measured. CPT-11 steady state flux was determined over a range of donor concentrations at pH 4 (0.5, 1, 5, 10, 15, 20 mg/ml) and pH 6.8 (0.5, 5, 10 mg/ml). Steady state flux increased linearly with increasing donor concentration of CPT-11 at pH 4 (r ² = 0.9935) and at pH 6.8 (r ² = 0.9886). CPT-11 permeability was independent of pH, although the distribution coefficient increased with increasing pH. Estimates of permeability for the lactone and carboxylate forms were 4.16 × 10^-5 cm/s and 2.6 × 10^-5 cm/s, respectively. These calculated permeability values were in agreement with the in vitro experimental data. Overall, CPT-11 was found to permeate through porcine buccal mucosa via passive diffusion. CPT-11 permeability was independent of pH, suggesting that the compound was transported mainly via a paracellular route. Overall, the results of this research suggest that the buccal route is a potential extravascular mode of delivery for CPT-11.

[Advances in the Treatment of Relapsed Small Cell Lung Cancer]

Small cell lung cancer (SCLC) is a highly malignant tumor. The initial treatment of radiotherapy and chemotherapy are more sensitive, high remission rate, but susceptible to drug resistance and relapse after treatment. Although the treatment of lung cancer has undergone enormous changes in recent years, treatment for relapsed SCLC is still a difficult problem in clinical field. In view of the serious resistance of recurrent SCLC to the existing chemotherapeutic drugs, the research on recurrent SCLC around the world is focused on the clinical trial of new drug development, optimization of chemotherapy regimen and target drug development. This paper summarize and estimate studies and literature reports of chemotherapy and precision therapy for relapsed SCLC, hopefully it could help clinicians treat relapsed SCLC and give us clinical research direction for relapsed SCLC in the future.

Irinotecan as a second-line chemotherapy for small cell lung cancer: a systemic analysis

PURPOSE

This analysis was conducted to evaluate the efficacy and safety of irinotecan based regimens as second-line chemotherapy in treating patients with small cell lung cancer.

METHODS

Clinical studies evaluating the efficacy and safety of irinotecan based regimens as second-line chemotherapy for patients with small cell lung cancer were identified using a predefined search strategy. Pooled response rates (RRs) of treatment were calculated.

RESULTS

In irinotecan based regimens as second-line chemotherapy, 4 clinical studies which including 155 patients with small cell lung cancer were considered eligible for inclusion. In all chemotherapy consisted of irinotecan with or without nedaplatin. Pooled analysis suggested that, in all patients, the pooled RR was 27.1% (42/155) in irinotecan based regimens. Nausea, vomiting, diarrhea and myelosuppression were the main side effects. No grade III or IV renal or liver toxicity was observed. No treatment related death occurred with the irinotecan based treatments.

CONCLUSION

This systemic analysis suggests that irinotecan based regimens as second-line chemotherapy are associated with mild response rate and acceptable toxicity for patients with small cell lung cancer.