Ferroptosis targeting natural compounds as a promising approach for developing potent liver cancer agents.

Liver cancer is the second leading cause of cancer-related death worldwide. However, treatment options, including surgical resection, transplantation, and molecular drug therapies, are of limited effectiveness. Recent studies have demonstrated that suppressing ferroptosis might be a pivotal signal for liver cancer initiation, thus providing a new way to combat liver cancer. Ferroptosis is a distinct form of controlled cell death that differs from conventional cell death routes like apoptosis, necrosis, and pyroptosis. It results from intracellular iron overload, which raises iron-dependent reactive oxygen species. This, in turn, leads to the accumulation of lipid peroxides that further result in oxidative damage to cell membranes, disrupt normal functioning, and ultimately speed up the ferroptosis phenomenon. Ferroptosis regulation is intricately linked to cellular physiological processes, encompassing iron metabolism, lipid metabolism, and the equilibrium between oxygen-free radical reactions and lipid peroxidation. This review intends to summarize the natural compounds targeting ferroptosis in liver cancer to offer new therapeutic ideas for liver cancer. Furthermore, it serves as the foundation for identifying and applying chemical medicines and natural chemicals that target ferroptosis to treat liver cancer efficiently.

Adherence to Advisory Committee on Immunization Practices in diabetes mellitus patients in Saudi Arabia: A multicenter retrospective study.

BACKGROUND: Patients with diabetes mellitus (DM) are predisposed to an increased risk of infection signifying the importance of vaccination to protect against its potentially severe complications. The Centers for Disease Control and Prevention/Advisory Committee on Immunization Practices (CDC/ACIP) issued immunization re-commendations to protect this patient population. AIM: To assess the adherence of patients with DM to the CDC/ACIP immunization recommendations in Saudi Arabia and to identify the factors associated with the vaccine adherence rate. METHODS: An observational retrospective study conducted in 2023 was used to collect data on the vaccination records from 13 diabetes care centers in Saudi Arabia with 1000 eligible patients in phase I with data collected through chart review and 709 patients in phase II through online survey. RESULTS: Among participants, 10.01% (n = 71) had never received any vaccine, while 85.89% (n = 609) received at least one dose of the coronavirus disease 2019 (COVID-19) vaccine, and 34.83% (n = 247) had received the annual influenza vaccine. Only 2.96% (n = 21), 2.11% (n = 15), and 1.12% (n = 8) received herpes zoster, tetanus, diphtheria, and pertussis (Tdap), and human papillomavirus (HPV) vaccines, respectively. For patients with DM in Saudi Arabia, the rate of vaccination for annual influenza and COVID-19 vaccines was higher compared to other vaccinations such as herpes zoster, Tdap, pneumococcal, and HPV. Factors such as vaccine recommendations provided by family physicians or specialists, site of care, income level, DM-related hospitalization history, residency site, hemoglobin A1c (HbA1c) level, and health sector type can significantly influence the vaccination rate in patients with DM. Among non-vaccinated patients with DM, the most reported barriers were lack of knowledge and fear of side effects. This signifies the need for large-scale research in this area to identify additional factors that might facilitate adherence to CDC/ACIP vaccine recommendations in patients with DM. CONCLUSION: In Saudi Arabia, patients with DM showed higher vaccination rates for annual influenza and COVID-19 vaccines compared to other vaccinations such as herpes zoster, Tdap, pneumococcal, and HPV. Factors such as vaccine recommendations provided by family physicians or specialists, the site of care, income level, DM-related hospitalization history, residency site, HbA1c level, and health sector type can significantly influence the vaccination rate in patients with DM.

Real-world analysis of integration of sacubitril/valsartan into clinical practice in Saudi Arabia.

Despite the demonstrated advantages of angiotensin receptor/neprilysin inhibitors in the management of heart failure, the pivotal Angiotensin-Neprilysin Inhibition versus Enalapril in Heart Failure (PARADIGM-HF) trial, which explored this class of medications, did not include individuals from Saudi Arabia. Recognizing that different nations and ethnic groups may exhibit unique characteristics, this study aimed to compare the demographics and outcomes of patients in Saudi Arabia who received sacubitril/valsartan (Sac/Val) with those enrolled in the PARADIGM-HF trial. In this retrospective, multicenter cohort study, we included all adult patients diagnosed with heart failure with reduced ejection fraction (HFrEF) within a tertiary healthcare system in Saudi Arabia between January 2018 and December 2021 and were initiated on Sac/Val. The primary objective was to compare the patient characteristics of those initiating Sac/Val treatment with the participants in the PARADIGM-HF trial. The secondary endpoints included the initiation setting, dose initiation, and titration, as well as alterations in B-type natriuretic peptide and ejection fraction at the 6-month mark. Furthermore, we reported the hospitalization and mortality event rates at the 12-month time point. The study included 400 patients with HFrEF receiving Sac/Val. Compared with the PARADIGM-HF trial, the cohort had a younger mean age and a higher prevalence of diabetes mellitus. SAC/VAL was prescribed as the initial therapy for 34% of the patients, while the remaining participants were initially treated with either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker before transitioning to Sac/Val. Approximately 75% of patients were initiated on 100 mg Sac/Val twice daily, and 90% initiated therapy in the inpatient setting. The mean ejection fraction significantly improved from 26.5 ±â€…8.4% to 30.5 ±â€…6.4% at 6 months (P < .001), while the median B-type natriuretic peptide level change was not significant (P = .39). Our study revealed notable disparities in the baseline characteristics of patients with HFrEF compared with those in the PARADIGM-HF trial. These findings offer valuable real-world insights into the prescription patterns and outcomes of Sac/Val in patients with HFrEF in Saudi Arabia, an aspect not previously represented in the PARADIGM-HF study.

Adefovir Dipivoxil as a Therapeutic Candidate for Medullary Thyroid Carcinoma: Targeting RET and STAT3 Proto-Oncogenes.

Aberrant gene expression is often linked to the progression of various cancers, making the targeting of oncogene transcriptional activation a potential strategy to control tumor growth and development. The RET proto-oncogene's gain-of-function mutation is a major cause of medullary thyroid carcinoma (MTC), which is part of multiple endocrine neoplasia type 2 (MEN2) syndrome. In this study, we used a cell-based bioluminescence reporter system driven by the RET promoter to screen for small molecules that potentially suppress the RET gene transcription. We identified adefovir dipivoxil as a transcriptional inhibitor of the RET gene, which suppressed endogenous RET protein expression in MTC TT cells. Adefovir dipivoxil also interfered with STAT3 phosphorylation and showed high affinity to bind to STAT3. Additionally, it inhibited RET-dependent TT cell proliferation and increased apoptosis. These results demonstrate the potential of cell-based screening assays in identifying transcriptional inhibitors for other oncogenes.

Distinct Mechanisms of Cytotoxicity in Novel Nitrogenous Heterocycles: Future Directions for a New Anti-Cancer Agent.

Electron-rich, nitrogenous heteroaromatic compounds interact more with biological/cellular components than their non-nitrogenous counterparts. The strong intermolecular interactions with proteins, enzymes, and receptors confer significant biological and therapeutic properties to the imidazole derivatives, giving rise to a well-known and extensively used range of therapeutic drugs used for infections, inflammation, and cancer, to name a few. The current study investigates the anti-cancer properties of fourteen previously synthesized nitrogenous heterocycles, derivatives of imidazole and oxazolone, on a panel of cancer cell lines and, in addition, predicts the molecular interactions, pharmacokinetic and safety profiles of these compounds. METHOD: The MTT and CellTiter-Glo® assays were used to screen the imidazole and oxazolone derivatives on six cancer cell lines: HL60, MDA-MB-321, KAIMRC1, KMIRC2, MCF-10A, and HCT8. Subsequently, in vitro tubulin staining and imaging were performed, and the level of apoptosis was measured using the Promega ApoTox-Glo® triplex assay. Furthermore, several computational tools were utilized to investigate the pharmacokinetics and safety profile, including PASS Online, SEA Search, the QikProp tool, SwissADME, ProTox-II, and an in silico molecular docking study on tubulin to identify the critical molecular interactions. RESULTS: In vitro analysis identified compounds 8 and 9 to possess the most significant potent cytotoxic activity on the HL60 and MDA-MB-231 cell lines, supported by PASS Online anti-cancer predictions with pa scores of 0.413 and 0.434, respectively. In addition, compound 9 induced caspase 3/7 dependent-apoptosis and interfered with tubulin polymerization in the MDA-MB-231 cell line, consistent with in silico docking results, identifying binding similarity to the native ligand colchicine. All the derivatives, including compounds 8 and 9, had acceptable pharmacokinetics; however, the safety profile was suboptimal for all the tested derivates except compound 4. CONCLUSION: The imidazole derivative compound 9 is a promising anti-cancer agent that switches on caspase-dependent apoptotic cell death and modulates microtubule function. Therefore, it could be a lead compound for further drug optimization and development.

Selective Antitumor Activity of Datelliptium toward Medullary Thyroid Carcinoma by Downregulating RET Transcriptional Activity.

Medullary thyroid carcinoma (MTC) is a rare aggressive form of thyroid cancer with high rates of metastasis. Sporadic and hereditary MTC are strongly driven by somatic and germline mutations, respectively, in the transmembrane REarranged during Transfection (RET) proto-oncogene, which encodes a receptor tyrosine kinase. Our previous study identified datelliptium as a novel RET transcription inhibitor, which stabilizes the RET G-quadruplex structures and suppresses RET oncogene transcription. The present study aimed to elucidate the effect of datelliptium on the suppression of epithelial-to-mesenchymal transition (EMT) and metastasis-related behaviors of MTC cells, including cell migration and formation of cancer stem cells (CSCs). Our results demonstrated that datelliptium downregulated the expression of the mesenchymal markers, including N-cadherin, vimentin, slug, snail, and claudin-1. Compared to untreated cells, datelliptium significantly decreased the migration of TT cells in a dose-dependent manner in a wound healing assay. Additionally, datelliptium significantly reduced the size of preformed spheroids from TT cells over the time course. Finally, datelliptium inhibited approximately 75% of MTC xenograft growth with minimal systemic toxicity. In conclusion, datelliptium exerts its antitumor activity against MTC cells by reducing the EMT program, migratory ability, and self-renewal capacity of TT cells, thus preventing invasive and metastatic behavior of MTC.

Salinomycin and its derivatives as potent RET transcriptional inhibitors for the treatment of medullary thyroid carcinoma.

Rearranged during transfection kinase (RET) is a validated molecular target in medullary thyroid cancer (MTC), as activating mutations in RET are often associated with the development of MTC. The present study reports the first preclinical characterization of salinomycin and selected analogs as potent RET transcriptional inhibitors. Reverse transcription­PCR and immunoblotting revealed that salinomycin profoundly decreased RET expression in the TT human MTC cell line by inhibiting RET transcription. Moreover, salinomycin resulted in remarkable anti­proliferative activity against MTC that is driven by RET (gain of function mutation) by selectively inhibiting the intracellular PI3K/Akt/mTOR signaling pathway. Also, flow cytometry and fluorescence­activated cell sorting showed that salinomycin induces G1 phase arrest and apoptosis by reducing the expression of retinoblastoma protein, E2F1, cyclin D and CDK4. The structure­activity relationship of salinomycin was investigated in this study. Some of the salinomycin derivatives showed the ability to reduce RET expression where others fail to alter RET expression. These results suggest that the RET­suppressing effect of salinomycin may be largely attributed to disruption of the Wnt pathway, presumably through interference with the ternary LRP6­Frizzled­Wnt complex. Furthermore, these findings support the further preclinical evaluation of salinomycin and its analogs as a promising new class of therapeutic agents for the improved treatment of MTC.

Interaction between Na-K-ATPase and Bcl-2 proteins BclXL and Bak.

In silico analysis predicts interaction between Na-K-ATPase (NKA) and Bcl-2 protein canonical BH3- and BH1-like motifs, consistent with NKA inhibition by the benzo-phenanthridine alkaloid chelerythrine, a BH3 mimetic, in fetal human lens epithelial cells (FHLCs) (Lauf PK, Heiny J, Meller J, Lepera MA, Koikov L, Alter GM, Brown TL, Adragna NC. Cell Physiol Biochem 31: 257-276, 2013). This report establishes proof of concept: coimmunoprecipitation and immunocolocalization showed unequivocal and direct physical interaction between NKA and Bcl-2 proteins. Specifically, NKA antibodies (ABs) coimmunoprecipitated BclXL (B-cell lymphoma extra large) and BAK (Bcl-2 antagonist killer) proteins in FHLCs and A549 lung cancer cells. In contrast, both anti-Bcl-2 ABs failed to pull down NKA. Notably, the molecular mass of BAK1 proteins pulled down by NKA and BclXL ABs appeared to be some 4-kDa larger than found in input monomers. In silico analysis predicts these higher molecular mass BAK1 proteins as alternative splicing variants, encoding 42 amino acid (aa) larger proteins than the known 211-aa long canonical BAK1 protein. These BAK1 variants may constitute a pool separate from that forming mitochondrial pores by specifically interacting with NKA and BclXL proteins. We propose a NKA-Bcl-2 protein ternary complex supporting our hypothesis for a special sensor role of NKA in Bcl-2 protein control of cell survival and apoptosis.

Surface-enhanced Raman spectroscopy (SERS) tracking of chelerythrine, a Na(+)/K(+) pump inhibitor, into cytosol and plasma membrane fractions of human lens epithelial cell cultures.

BACKGROUND/AIMS: The quaternary benzo-phenanthridine alkaloid (QBA) chelerythrine (CET) is a pro-apoptotic drug and Na(+)/K(+) pump (NKP) inhibitor in human lens epithelial cells (HLECs). In order to obtain further insight into the mechanism of NKP inhibition by CET, its sub-cellular distribution was quantified in cytosolic and membrane fractions of HLEC cultures by surface-enhanced Raman spectroscopy (SERS). METHODS: Silver nanoparticles (AgNPs) prepared by the Creighton method were concentrated, and size-selected using a one-step tangential flow filtration approach. HLECs cultures were exposed to 50 µM CET in 300 mOsM phosphate-buffered NaCl for 30 min. A variety of cytosolic extracts, crude and purified membranes, prepared in lysing solutions in the presence and absence of a non-ionic detergent, were incubated with AgNPs and subjected to SERS analysis. Determinations of CET were based on a linear calibration plot of the integrated CET SERS intensity at its 659 cm(-1) marker band as a function of CET concentration. RESULTS: SERS detected chemically unaltered CET in both cytosol and plasma membrane fractions. Normalized for protein, the CET content was some 100 fold higher in the crude and purified plasma membrane fraction than in the soluble cytosolic extract. The total free CET concentration in the cytosol, free of membranes or containing detergent-solubilized membrane material, approached that of the incubation medium of HLECs. CONCLUSION: Given a negative membrane potential of HLECs the data suggest, but do not prove, that CET may traverse the plasma membrane as a positively charged monomer (CET(+)) accumulating near or above passive equilibrium distribution. These findings may contribute to a recently proposed hypothesis that CET binds to and inhibits the NKP through its cytosolic aspect.