R. Cardnell

Bio: R. Cardnell is an academic researcher from University of Texas MD Anderson Cancer Center. The author has contributed to research in topics: Cancer & DNA damage. The author has an hindex of 2, co-authored 4 publications receiving 9 citations.

A wake-up call for cancer DNA damage: the role of Schlafen 11 (SLFN11) across multiple cancers

Abstract: DNA-damaging agents exploit increased genomic instability, a hallmark of cancer. Recently, inhibitors targeting the DNA damage response (DDR) pathways, such as PARP inhibitors, have also shown promising therapeutic potential. However, not all tumors respond well to these treatments, suggesting additional determinants of response are required. Schlafen 11 (SLFN11), a putative DNA/RNA helicase that induces irreversible replication block, is emerging as an important regulator of cellular response to DNA damage. Preclinical and emerging clinical trial data suggest that SLFN11 is a predictive biomarker of response to a wide range of therapeutics that cause DNA damage including platinum salts and topoisomerase I/II inhibitors, as well as PARP inhibitors, which has raised exciting possibilities for its clinical application. In this article, we review the function, prevalence, and clinical testing of SLFN11 in tumor biopsy samples and circulating tumor cells. We discuss mounting evidence of SLFN11 as a key predictive biomarker for a wide range of cancer therapeutics and as a prognostic marker across several cancer types. Furthermore, we discuss emerging areas of investigation such as epigenetic reactivation of SLFN11 and its role in activating immune response. We then provide perspectives on open questions and future directions in studying this important biomarker.

New molecular classification of large cell neuroendocrine carcinoma and small cell lung carcinoma with potential therapeutic impacts

Abstract: Large cell neuroendocrine carcinoma (LCNECs) and small cell lung carcinomas (SCLCs) are high-grade neuroendocrine carcinomas of the lung with very aggressive behavior and poor prognosis. Their histological classification as well as their therapeutic management has not changed much in recent years, but genomic and transcriptomic analyses have revealed different molecular subtypes raising hopes for more personalized treatment. Indeed, four subtypes of SCLCs have been recently described, SCLC-A driven by the master gene ASCL1, SCLC-N driven by NEUROD1, SCLC-Y by YAP1 and SCLC-P by POU2F3. Whereas SCLC standard of care is based on concurrent chemoradiation for limited stages and on chemotherapy alone or chemotherapy combined with anti-PD-L1 checkpoint inhibitors for extensive stage SCLC, SCLC-A variants could benefit from DLL3 or BCL2 inhibitors, and SCLC-N variants from Aurora kinase inhibitors combined with chemotherapy, or PI3K/mTOR or HSP90 inhibitors. In addition, a new SCLC variant (SCLC-IM) with high-expression of immune checkpoints has been also reported, which could benefit from immunotherapies. PARP inhibitors also gave promising results in combination with chemotherapy in a subset of SCLCs. Regarding LCNECs, they represent a heterogeneous group of tumors, some of them exhibiting mutations also found in SCLC but with a pattern of expression of NSCLC, while others harbor mutations also found in NSCLC but with a pattern of expression of SCLC, questioning their clinical management as NSCLCs or SCLCs. Overall, we are probably entering a new area, which, if personalized treatments are effective, will also lead to the implementation in practice of molecular testing or biomarkers detection for the selection of patients who can benefit from them.

Drug targets, mechanisms of drug action, and therapeutics against SARS-CoV-2

Abstract: The recent outbreak of COVID-19 has affected human lives severely. The human-to-human transmission of this viral disease has become deadly due to the unavailability of COVID-19 specific drugs. Here, an overview of various attempts made to design different therapeutic agents against various structural and non-structural proteins of SARS-CoV-2 has been summarized. Emphasis has been made to highlight the mechanisms of drug action and ways to design better inhibitors of these proteins. The roles of anti-oxidants and vitamins in suppressing COVID-19 are also discussed.

Precision Oncology with Drugs Targeting the Replication Stress, ATR, and Schlafen 11.

Abstract: Precision medicine aims to implement strategies based on the molecular features of tumors and optimized drug delivery to improve cancer diagnosis and treatment. DNA replication is a logical approach because it can be targeted by a broad range of anticancer drugs that are both clinically approved and in development. These drugs increase deleterious replication stress (RepStress); however, how to selectively target and identify the tumors with specific molecular characteristics are unmet clinical needs. Here, we provide background information on the molecular processes of DNA replication and its checkpoints, and discuss how to target replication, checkpoint, and repair pathways with ATR inhibitors and exploit Schlafen 11 (SLFN11) as a predictive biomarker.

Efficacy and safety of PD-1/PD-L1 inhibitor plus chemotherapy versus chemotherapy alone as first-line treatment for extensive-stage small cell lung cancer: A systematic review and meta-analysis.

Abstract: BACKGROUND Immunotherapy has afforded new treatment options for extensive small cell lung cancer (ES-SCLC). However, reports on the effectiveness of immune checkpoint inhibitors (ICIs) combined with chemotherapy on survival in ES-SCLC patients are inconsistent. Therefore, we conducted a meta-analysis on the efficacy and safety of ICI combined with chemotherapy for ES-SCLC. METHODS We searched for randomized controlled clinical trials related to first-line treatment of ES-SCLC with ICI combined with chemotherapy in PUBMED, ESMO, ASCO, and WCLC since 2018. The primary outcome was overall survival (OS). RESULTS Four studies were included. Compared to chemotherapy alone, ICI in combination with chemotherapy as first-line treatment reduced the risk of death (hazard ratio [HR]: 0.76; 95% CI: 0.68-0.86; P < 0.00001) and disease progression (HR: 0.76; 95% CI: 0.68-0.84; P < 0.00001). The objective response rate (ORR) with ICI plus chemotherapy was significantly higher than that with chemotherapy alone (HR: 1.10; 95% CI: 1.02-1.19, P = 0.01). The duration of response (DoR) rate at one year was also better with ICI plus chemotherapy (HR: 3.46; 95% CI: 2.24-5.33; P < 0.00001). Security analysis revealed that the incidence of immune-mediated adverse events (imAEs) (HR: 3.77; 95% CI: 1.99-7.15, P < 0.0001) and grade 3/4 imAEs (HR: 7.01; 95% CI: 2.48-19.81; P = 0.0002) increased significantly with ICI plus chemotherapy. CONCLUSIONS ICI combined with chemotherapy as first-line treatment can significantly improve the OS and progression-free survival (PFS) of ES-SCLC patients, but the toxicity caused by immunotherapy should be carefully considered. KEY POINTS Significant findings of the studyOur meta-analysis shows that PD-L1/PD-1 plus chemotherapy can significantly improve the OS and PFS of ES-SCLC patients when used as first-line therapy. WHAT THIS STUDY ADDS This study fills gaps regarding the efficacy of immunotherapy combined with chemotherapy as first-line treatment for ES-SCLC, and provides better evidence for the use of PD-L1/PD-1 immunotherapy plus chemotherapy for patients with ES-SCLC.

Immunotherapy in Extensive-Stage Small Cell Lung Cancer.

Abstract: Small cell lung cancer (SCLC) remains a poorly understood disease with aggressive features, high relapse rates, and significant morbidity as well as mortality, yet persistently limited treatment options. For three decades, the treatment algorithm of SCLC has been stagnant despite multiple attempts to find alternative therapeutic options that could improve responses and increase survival rates. On the other hand, immunotherapy has been a thriving concept that revolutionized treatment options in multiple malignancies, rendering previously untreatable diseases potentially curable. In extensive stage SCLC, immunotherapy significantly altered the course of disease and is now part of the treatment algorithm in the first-line setting. Nevertheless, the important questions that arise are how best to implement immunotherapy, who would benefit the most, and finally, how to enhance responses.