A 5-Fluorouracil Derivative: Carmofur as a New Potent Agent for Inhibition of Human Prostate and Breast Cancer Cell Lines

Taming the storm: potential anti-inflammatory compounds targeting SARS-CoV-2 MPro

In severe COVID-19 cases, an exacerbated inflammatory response triggers a cytokine storm that can worsen the prognosis. Compounds with both antiviral and anti-inflammatory activities show promise as candidates for COVID-19 therapy, as they potentially act against the SARS-CoV-2 infection regardless of the disease stage. One of the most attractive drug targets among coronaviruses is the main protease (MPro). This enzyme is crucial for cleaving polyproteins into non-structural proteins required for viral replication. The aim of this review was to identify SARS-CoV-2 MPro inhibitors with both antiviral and anti-inflammatory properties. The interactions of the compounds within the SARS-CoV-2 MPro binding site were analyzed through molecular docking when data from crystallographic structures were unavailable. 18 compounds were selected and classified into five different superclasses. Five of them exhibit high potency against MPro: GC-376, baicalein, naringenin, heparin, and carmofur, with IC50 values below 0.2 μM. The MPro inhibitors selected have the potential to alleviate lung edema and decrease cytokine release. These molecules mainly target three critical inflammatory pathways: NF-κB, JAK/STAT, and MAPK, all previously associated with COVID-19 pathogenesis. The structures of the compounds occupy the S1/S2 substrate binding subsite of the MPro. They interact with residues from the catalytic dyad (His41 and Cys145) and/or with the oxyanion hole (Gly143, Ser144, and Cys145), which are pivotal for substrate recognition. The MPro SARS-CoV-2 inhibitors with potential anti-inflammatory activities present here could be optimized for maximum efficacy and safety and be explored as potential treatment of both mild and severe COVID-19.

Cytotoxic and Apoptotic Impacts of Ceranib-2 on RAW 264.7 Macrophage Cells

BACKGROUND

Many ceramidase inhibitors have been developed and identified as potential treatment agents for various types of tumors in the last several decades. In recent years, their therapeutic potential against tumors has gained great attention. Inhibition of ceramidase is r eportedly related to apoptosis and cytotoxicity in macrophages, which are closely related to tumor development and progression. However, whether and how ceranib-2, a novel ceramidase inhibitor, can exert its cytotoxic and apoptotic effects on RAW 264.7, a macrophage cell line established from a tumor in a male mouse induced with the Abelson murine leukemia virus, remains unknown.

OBJECTIVE

In this study, we aimed to investigate whether and how ceranib-2 can exert cytotoxic, antiproliferative, and apoptotic effects on the RAW264.7 macrophages.

METHODS

We performed the MTT assay, Annexin V staining assay, and confocal microscopy to detect the cytotoxicity, apoptosis, and morphological changes, respectively, in the RAW264.7 cells.

RESULTS

The viability of RAW264.7 cells treated with ceranib-2 was decreased as the doses of ceranib-2 increased at 24 h and 48 h due to apoptosis resulting from ceranib-2-reduced integrity of the mitochondrial membrane. Moreover, morphological changes were observed in these ceranib-2 exposed cells, further indicating the role of ceranib-2 in inducing apoptosis in these cells.

CONCLUSION

Ceranib-2 is cytotoxic to RAW 264.7 macrophages and can induce apoptosis in these cells.

Targeting the Sphingolipid Rheostat in Gliomas

Gliomas are highly aggressive cancer types that are in urgent need of novel drugs and targeted therapies. Treatment protocols have not improved in over a decade, and glioma patient survival remains among the worst of all cancer types. As a result, cancer metabolism research has served as an innovative approach to identifying novel glioma targets and improving our understanding of brain tumors. Recent research has uncovered a unique metabolic vulnerability in the sphingolipid pathways of gliomas that possess the IDH1 mutation. Sphingolipids are a family of lipid signaling molecules that play a variety of second messenger functions in cellular regulation. The two primary metabolites, sphingosine-1-phosphate (S1P) and ceramide, maintain a rheostat balance and play opposing roles in cell survival and proliferation. Altering the rheostat such that the pro-apoptotic signaling of the ceramides outweighs the pro-survival S1P signaling in glioma cells diminishes the hallmarks of cancer and enhances tumor cell death. Throughout this review, we discuss the sphingolipid pathway and identify the enzymes that can be most effectively targeted to alter the sphingolipid rheostat and enhance apoptosis in gliomas. We discuss each pathway’s steps based on their site of occurrence in the organelles and postulate novel targets that can effectively exploit this vulnerability.