Stimulated Raman scattering microscopy with spectral phasor analysis: applications in assessing drug–cell interactions

Statins have displayed significant, although heterogeneous, anti-tumour activity in breast cancer disease progression and recurrence. They offer promise as a class of drugs, normally used for cardiovascular disease control, that could have a significant impact on the treatment of cancer. Understanding their mode of action and accurately assessing their efficacy on live cancer cells is an important and significant challenge. Stimulated Raman scattering (SRS) microscopy is a powerful, label-free imaging technique that can rapidly characterise the biochemical responses of live cell populations following drug treatment. Here, we demonstrate multi-wavelength SRS imaging together with spectral phasor analysis to characterise a panel of breast cancer cell lines (MCF-7, SK-BR-3 and MDA-MB-231 cells) treated with two clinically relevant statins, atorvastatin and rosuvastatin. Label-free SRS imaging within the high wavenumber region of the Raman spectrum (2800–3050 cm⁻¹) revealed the lipid droplet distribution throughout populations of live breast cancer cells using biocompatible imaging conditions. A spectral phasor analysis of the hyperspectral dataset enables rapid differentiation of discrete cellular compartments based on their intrinsic SRS characteristics. Applying the spectral phasor method to studying statin treated cells identified a lipid accumulating phenotype in cell populations which displayed the lowest sensitivity to statin treatment, whilst a weaker lipid accumulating phenotype was associated with a potent reduction in cell viability. This study provides an insight into potential resistance mechanisms of specific cancer cells towards treatment with statins. Label-free SRS imaging provides a novel and innovative technique for phenotypic assessment of drug-induced effects across different cellular populations and enables effective analysis of drug–cell interactions at the subcellular scale.

Stimulated Raman scattering microscopy with spectral phasor analysis provides a label-free approach for phenotypic evaluation of drug-induced effects.     

The Effects of Statins on Neurotransmission and Their Neuroprotective Role in Neurological and Psychiatric Disorders

Statins are among the most widely used drug classes in the world. Apart from their basic mechanism of action, which is lowering cholesterol levels, many pleiotropic effects have been described so far, such as anti-inflammatory and antiatherosclerotic effects. A growing number of scientific reports have proven that these drugs have a beneficial effect on the functioning of the nervous system. The first reports proving that lipid-lowering therapy can influence the development of neurological and psychiatric diseases appeared in the 1990s. Despite numerous studies about the mechanisms by which statins may affect the functioning of the central nervous system (CNS), there are still no clear data explaining this effect. Most studies have focused on the metabolic effects of this group of drugs, however authors have also described the pleiotropic effects of statins, pointing to their probable impact on the neurotransmitter system and neuroprotective effects. The aim of this paper was to review the literature describing the impacts of statins on dopamine, serotonin, acetylcholine, and glutamate neurotransmission, as well as their neuroprotective role. This paper focuses on the mechanisms by which statins affect neurotransmission, as well as on their impacts on neurological and psychiatric diseases such as Parkinson’s disease (PD), Alzheimer’s disease (AD), vascular dementia (VD), stroke, and depression. The pleiotropic effects of statin usage could potentially open floodgates for research in these treatment domains, catching the attention of researchers and clinicians across the globe.     

Occurrence and spatial distribution of statins,fibrates and their metabolites in aquatic environments

Due to widespread occurrence of lipid lowering drugs such as statins, fibrates and their metabolites in the aquatic environments, there is a worldwide growing concern in their role in water quality and aquatic biota. However, this concern is limited by ability to address their occurrence, distribution, fate and eco-toxicological effects. This study focuses on the quantification of the levels of statins, fibrates and their metabolites in the aquatic environments using Ultra-High Performance Liquid Chromatography coupled to high resolution quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS). The developed UHPLC–QTOF–MS based method was successfully applied to the analysis of statins, fibrates and metabolites in real water samples collected from Daspoort WWWs influent and effluent and Apies River. A series of statin compounds (mevastatin, simvastatin, pravastatin, rosuvastatin, fluvastatin, atorvastatin), fibrates (gemfibrozil, fenofibrate) and the corresponding metabolites (clofibric and fenofibric acids) were detected and quantified in the range of 0.56–19.90 µg/L in both waste and River water samples. In general, the results of the present study are an indication of pollution hazards from wastewater treatment processes and these levels poses a huge risk to the growth and reproduction of aquatic organisms. Thus, regulating the limit levels of statins, fibrates and metabolites in any type of water is paramount as it will provide the vital information on the toxic risks associated with organic pollutants of pharmaceutical origin.     

Serendipitous fragment-based drug discovery: ketogenic diet metabolites and statins effectively inhibit several carbonic anhydrases

Acetoacetic acid and R-3-hydroxy-butyric acid (BHB) are "ketone bodies", metabolites produced during the ketogenic diet. We discovered that they inhibit in the submicromolar-micromolar range several carbonic anhydrase (CA, EC 4.2.1.1) isoforms involved in relevant physiologic processes such as lipogenesis and tumorigenesis. The BHB fragment is also present in the molecules of most statins, widely used drugs for inhibiting cholesterol biosynthesis through the 3-hydroxy-3-methyl-glutaryl-CoA reductase pathway. Three such statins, atorvastatin, fluvastatin and rosuvastatin, showed submicromolar-low nanomolar inhibition of the fifteen human isoforms hCA I-XIV. Our data point out that in addition to their cholesterol lowering properties, these drugs may exert a therapeutic effect by inhibiting lipogenesis through mitochondrial CA inhibition. The statins are also low nanomolar inhibitors of the tumor-associated isoforms CA IX and XII. Based on the BHB/statin scaffolds, antiepileptic, antiobesity and antitumor compounds with higher affinity for the various CA isoforms involved in epileptogenesis (CA VA, VB, VII), lipogenesis (CA III, CA VA, CA VB) and tumorigenesis (CA IX and CA XII) may be designed.     

他汀类药物用于急性冠脉综合症的潜在作用

急性冠脉综合症是易损粥样硬化斑块破裂的结果，斑块的稳定可以通过改变生活方式及适当的药物治疗而达到。有证据表明，他汀类的一个主要有益作用是诱导斑块稳定和消退。他汀类除了降低胆固醇中低密度脂蛋白外，还具有多种多效性或不从属于胆固醇的作用，在这些多效性作用中有内皮功能、平滑肌细胞、血栓形成／血小板功能和炎症的改善，使之特别适合急性冠脉综合症患者选择。     

Genetic Modification Approaches for Parasporins Bacillus thuringiensis Proteins with Anticancer Activity

Bacillus thuringiensis (Bt) is a bacterium capable of producing Cry toxins, which are recognized for their bio-controlling actions against insects. However, a few Bt strains encode proteins lacking insecticidal activity but showing cytotoxic activity against different cancer cell lines and low or no cytotoxicity toward normal human cells. A subset of Cry anticancer proteins, termed parasporins (PSs), has recently arisen as a potential alternative for cancer treatment. However, the molecular receptors that allow the binding of PSs to cells and their cytotoxic mechanisms of action have not been well established. Nonetheless, their selective cytotoxic activity against different types of cancer cell lines places PSs as a promising alternative treatment modality. In this review, we provide an overview of the classification, structures, mechanisms of action, and insights obtained from genetic modification approaches for PS proteins.     

Chemical and biotechnological developments in organotin cancer chemotherapy

This review provides a substantial knowledge on the action mode of organotins in cancer chemotherapy. The coordinating ability of organotin compounds towards DNA and cancer cells is discussed. Most of the organotins tested are DNA-targeted and mitotic, the action mode occurring via a gene-mediated pathway. These potential anti-cancer drugs are actually being studied widely, and whilst they are efficacious and perhaps curative against a select number of neoplasias, suffer from a variety of deficiencies, notably severe systemic toxicity and a tendency to elicit drug resistance.     

HMG-CoA Reductase Inhibitor Regulates Endothelial Progenitor Function Through the Phosphatidylinositol 3′-Kinase/AKT Signal Transduction Pathway

HMG-CoA reductase inhibitor (statins) are known to have pleiotropic effects. We examined the effect and mechanism of simvastatin on peripheral endothelial progenitor cells (EPCs). Rats were divided into simvastatin group and the control group after cardiac infarction operation. Simvastatin treatment significantly increased the number of peripheral blood CD34+ CD133+ cells, and serum concentration of vascular endothelial growth factor (VEGF) and AKT was markedly increased in vivo. In cultured EPC, simvastatin increased the concentrations of VEGF, AKT and eNOS. Western blots analysis showed that simvastatin increased the phosphorylation of eNOS and FKHRL1, which can be blocked by the PI3K/AKT pathway blocker LY294002 . Our study demonstrated that simvastatin increases the mobilization of EPCs after cardiac infarction. In in vitro study, simvastatin increases the phosphorylation of eNOS and of FKHRL1 through the PI3K/AKT signaling pathway.     

The analytical determination of isoprenoid intermediates from the mevalonate pathway

In this article, assays on the analytical determination of farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP), two important isoprenoid intermediates at biochemically relevant branching points in the mevalonate pathway, are summarized and reviewed. There is considerable recent interest in the measurement of these two isoprenoids because of their direct involvement in several diseases, for example, statins lower cholesterol by inhibiting 3-hydroxy-3-methylglutaryl-CoA reductase but equally affect other metabolite biosyntheses. The isoprenoids FPP and GGPP are key intermediates due to their role as CaaX-specific substrates for posttranslational modification of proteins (protein prenylation). Disease pathologies and therapeutic efficacy of different treatments (e.g., cholesterol-lowering drugs) may lead to a reduction in isoprenoid levels and an accompanying reduction in prenylation of specific proteins. To understand the exact biochemical role of the isoprenoids FPP and GGPP, we need to know their levels. Several recent studies have shown exact levels of FPP and GGP in plasma and relevant tissues and their modulation following treatment. Furthermore, by directly measuring the extent of protein prenylation and identifying target proteins, further insight into the exact biochemical nature of the pathology and regulatory mechanisms will be possible. This short review aims to highlight the relevant literature on the analytical determination of the free isoprenoids FPP and GGPP in biological tissue as well as techniques for directly measuring prenylated proteins.     

Sialyltransferase Inhibitors for the Treatment of Cancer Metastasis: Current Challenges and Future Perspectives

Potent, cell-permeable, and subtype-selective sialyltransferase inhibitors represent an attractive family of substances that can potentially be used for the clinical treatment of cancer metastasis. These substances operate by specifically inhibiting sialyltransferase-mediated hypersialylation of cell surface glycoproteins or glycolipids, which then blocks the sialic acid recognition pathway and leads to deterioration of cell motility and invasion. A vast amount of evidence for the in vitro and in vivo effects of sialyltransferase inhibition or knockdown on tumor progression and tumor cell metastasis or colonization has been accumulated over the past decades. In this regard, this review comprehensively discusses the results of studies that have led to the recent discovery and development of sialyltransferase inhibitors, their potential biomedical applications in the treatment of cancer metastasis, and their current limitations and future opportunities.     

Triptolide downregulates Rac1 and the JAK/STAT3 pathway and inhibits colitis-related colon cancer progression

Triptolide, a diterpenoid triepoxide from the traditional Chinese medicinal herb Tripterygium wilfordii Hook. f., is a potential treatment for autoimmune diseases as well a possible anti-tumor agent. It inhibits proliferation of coloretal cancer cells in vitro and in vivo. In this study, its ability to block progress of colitis to colon cancer, and its molecular mechanism of action are investigated. A mouse model for colitis-induced colorectal cancer was used to test the effect of triptolide on cancer progression. Treatment of mice with triptolide decreased the incidence of colon cancer formation, and increased survival rate. Moreover, triptolide decreased the incidence of tumors in nude mice inoculated with cultured colon cancer cells dose-dependently. In vitro, triptolide inhibited the proliferation, migration and colony formation of colon cancer cells. Secretion of IL6 and levels of JAK1, IL6R and phosphorylated STAT3 were all reduced by triptolide treatment. Triptolide prohibited Rac1 activity and blocked cyclin D1 and CDK4 expression, leading to G1 arrest. Triptolide interrupted the IL6R-JAK/STAT pathway that is crucial for cell proliferation, survival, and inflammation. This suggests that triptolide might be a candidate for prevention of colitis induced colon cancer because it reduces inflammation and prevents tumor formation and development.     

Emerging Approaches in Fermentative Production of Statins

Microbial metabolites have many important applications in pharmaceutical and health-care industry. The products of microbial origin are usually produced by submerged fermentation. The solid-state fermentation represents an alternative mode of fermentation, which is increasingly being employed as an alternative to submerged fermentation for metabolite production. The prospect of producing high-value product using low-value raw material offers a substantial premium to switch to these technologies. The cost of statins being one major factor, solid-state fermentation with agro-industrial residues as carbon, nitrogen and support matrix, promises to substantially lower the cost of production. Hence, newer approaches are required to exploit the agro-industrial residues for statin production. The development of these technologies offers an opportunity to exploit low-cost substrates without substantial investment in newer production methodologies. The emerging evidence of beneficial effect of statins in applications other than lipid lowering such as in Alzheimer disease, HIV, age-related dementia, and cancer chemotherapy makes it very important to develop methods for economic production of statins.     

The Anticancer Peptide CIGB-552 Exerts Anti-Inflammatory and Anti-Angiogenic Effects through COMMD1

CIGB-552 is a synthetic anti-tumor peptide capable of reducing tumor size and increasing the lifespan of tumor-bearing mice. Part of its anti-cancer effects consists of inducing apoptosis, modulating NF-kB signaling pathway, and the angiogenesis process. Although one of its major mediators, the COMMD1 protein, has been identified, the mechanism by which CIGB-552 exerts such effects remains elusive. In the present study, we show the role of COMMD1 in CIGB-552 mechanism of action by generating the COMMD1 knock-out from the human lung cancer cell line NCI-H460. A microarray was performed to analyze both wild-type and KO cell lines with regard to CIGB-552 treatment. Additionally, different signaling pathways were studied in both cell lines to validate the results. Furthermore, the interaction between CIGB-552 and COMMD1 was analyzed by confocal microscopy. By signaling pathway analysis we found that genes involved in cell proliferation and apoptosis, oncogenic transformation, angiogenesis and inflammatory response are potentially regulated by the treatment with CIGB-552. We then demonstrated that CIGB-552 is capable of modulating NF-kB in both 2D and 3D cell culture models. Finally, we show that the ability of CIGB-552 to negatively modulate NF-kB and HIF-1 pathways is impaired in the COMMD1 knock-out NCI-H460 cell line, confirming that COMMD1 is essential for the peptide mechanism of action.     

Study on the conversion of three natural statins from lactone forms to their corresponding hydroxy acid forms and their determination in Pu-Erh tea

Conversions of statins, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, from lactone forms to their corresponding hydroxy acid form in 0.1 N NaOH or 0.05 N KOH (prepared with 25, 50, 75, 90% acetonitrile or methanol in water or 100% water) were evaluated. Results showed that lactone form statins could be transformed almost completely only in alkaline solutions prepared with 25 or 50% acetonitrile. In all methanolic alkaline solutions, lactone form statins could also be converted entirely, nevertheless, they would be further transformed to the methyl ester of the hydroxy acid form and the transformation increased as methanol rises. When lactone and hydroxy acid forms of statins were in methanol, ethyl acetate, 70% acetonitrile in water (with 0.5% acetic acid or no) for 0-48 h at room temperature or in 100 degrees C water for 0-2 h, lactone form statins were converted to their corresponding hydroxy acids, which were raised as time extends and the highest conversions of them were about 35% in 100 degrees C water and 70% acetonitrile, slightly transformed for lactone form statins in 70% acetonitrile (with 0.5% acetic acid) after 8 h, and the other treatments for all statins showed no significant changes. Interferences would be reduced efficiently when statins were extracted from Pu-Erh tea with methanol, ethyl acetate or 100 degrees C water followed by purifying through a C18 solid-phase extraction cartridge. Lovastatin was the only statin found in Pu-Erh tea and the highest content of it was found under ethyl acetate extraction. In ethyl acetate and methanol extracts, lovastatin existed merely as lactone form. The lowest content of lovastatin was found in the 100 degrees C water extract of Pu-Erh tea, however, both of lactone and hydroxy acid forms were found to exist in the extract.     

Combined inhibition of HDAC and DNMT1 induces p85α/MEKmediated cell cycle arrest by dual target inhibitor 208 in U937 cells

Herein we reported an efficient dual DNMT and HDAC inhibitor 208 with great antiproliferative activity against U937 cells. Further studies revealed 208 affected the whole proteome profile and could induce G1 cell cycle arrest and apoptosis in U937 cells through upregulating CDK inhibitor p16 and downregulating cyclin-dependent kinases and their activators.     

Is Curcumin the Answer to Future Chemotherapy Cocktail?

The rise in cancer cases in recent years is an alarming situation worldwide. Despite the tremendous research and invention of new cancer therapies, the clinical outcomes are not always reassuring. Cancer cells could develop several evasive mechanisms for their survivability and render therapeutic failure. The continuous use of conventional cancer therapies leads to chemoresistance, and a higher dose of treatment results in even greater toxicities among cancer patients. Therefore, the search for an alternative treatment modality is crucial to break this viscous cycle. This paper explores the suitability of curcumin combination treatment with other cancer therapies to curb cancer growth. We provide a critical insight to the mechanisms of action of curcumin, its role in combination therapy in various cancers, along with the molecular targets involved. Curcumin combination treatments were found to enhance anticancer effects, mediated by the multitargeting of several signalling pathways by curcumin and the co-administered cancer therapies. The preclinical and clinical evidence in curcumin combination therapy is critically analysed, and the future research direction of curcumin combination therapy is discussed.     

Statin inhibits interferon-gamma-induced expression of intercellular adhesion molecule-1 (ICAM-1) in vascular endothelial and smooth muscle cells

Inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, known as statins, are widely used for primary and secondary prevention of coronary artery atherosclerosis. Pathogenesis of atherosclerosis is multistep processes where transendothelial migration of various leukocytes including monocytes is a crucial step. Interferon-gamma (IFN-gamma) contributes in this process by activating macrophages and T-lymphocytes, and by inducing adhesion molecules in vascular endothelial and smooth muscle cells. In this study we investigated the expression of intercellular cell adhesion molecule-1 (ICAM-1) in transformed endothelial cell line ECV304 cells as influenced by lovastatin, tumor necrosis factor-alpha (TNF-alpha) and IFN-gamma. Results show that lovastatin suppresses expression of ICAM-1 by inhibiting the IFN-gamma-induced extracellular signal-regulated kinase (ERK) p44/p42-STAT1 signaling pathway. In cells treated with lovastatin and IFN-gamma, ICAM-1 was expressed at a lower level than in cells treated with IFN-gamma alone. However, lovastatin does not reduce TNF-alpha induced expression of ICAM-1. A similar result was observed in cells treated with the MEKK inhibitor PD98059 and IFN-gamma. Cis-acting DNA sequence elements were identified in the 5'-flanking region of the ICAM-1 promoter that mediate inhibition by lovastatin; these sequences map to the IFN-gamma activated site which also binds the STAT1 homodimer. However, lovastatin did not inhibit IFN-gamma-mediated induction of the Y701 phosphorylated form of STAT1. But lovastatin does inhibit the IFN-gamma-mediated phosphorylation of ERK1/ERK2 (T202/Y204) and S727 phosphorylation of STAT1. TNF-alpha does not induce phosphorylation of ERK1/ERK2 and S727 in ECV304 and smooth muscle cells. The results provide the evidences that statins may have beneficial effects by inhibiting IFN-gamma action in atherosclerotic process     

Spectrally and Time-Resolved Fluorescence Imaging of 22-NBD-Cholesterol in Human Peripheral Blood Mononuclear Cells in Chronic Kidney Disease Patients

The interaction of the fluorescent probe 22-NBD-cholesterol with membranes of human peripheral blood mononuclear cells (PBMC) was tested by time- and spectrally resolved fluorescence imaging to monitor the disturbance of lipid metabolism in chronic kidney disease (CKD) and its treatment with statins. Blood samples from healthy volunteers (HV) and CKD patients, either treated or untreated with statins, were compared. Spectral imaging was done using confocal microscopy at 16 spectral channels in response to 458 nm excitation. Time-resolved imaging was achieved by time-correlated single photon counting (TCSPC) following excitation at 475 nm. The fluorescence of 22-NBD-cholesterol was mostly integrated into plasmatic membrane and/or intracellular membrane but was missing from the nuclear region. The presence of two distinct spectral forms of 22-NBD-cholesterol was uncovered, with significant variations between studied groups. In addition, two fluorescence lifetime components were unmasked, changing in CKD patients treated with statins. The gathered results indicate that 22-NBD-cholesterol may serve as a tool to study changes in the lipid metabolism of patients with CKD to monitor the effect of statin treatment.     

Insulin Receptor Substrate 1 Is Involved in the Phycocyanin-Mediated Antineoplastic Function of Non-Small Cell Lung Cancer Cells

Phycocyanin, derived from marine algae, is known to have noteworthy antineoplastic properties. However, the underlying mechanism involved in phycocyanin-mediated anti-growth function on non-small cell lung cancer (NSCLC) cells is still ambiguous. Here, we investigated the mechanism of action of phycocyanin on H1299, A549, and LTEP-a2 cells. According to the results obtained, insulin receptor substrate 1 (IRS-1) expression was reduced by phycocyanin. Cell phenotype tests showed that siRNA knockdown of IRS-1 expression significantly inhibited the growth, migration, colony formation, but promoted the apoptosis of NSCLC cells. Meanwhile, phycocyanin and IRS-1 siRNA treatment both reduced the PI3K-AKT activities in NSCLC cells. Moreover, overexpression of IRS-1 accelerated the proliferation, colony formation, and migration rate of H1299, A549, and LTEP-a2 cells, which was contradicting to the knockdown results. Overall, this study uncovered a regulatory mechanism by which phycocyanin inhibited the growth of NSCLC cells via IRS-1/AKT pathway, laying the foundation for the potential target treatment of NSCLC.     

Green Synthesis of Gold Nanoparticles Using Plant Extracts as Beneficial Prospect for Cancer Theranostics

Gold nanoparticles (AuNPs) have been widely explored and are well-known for their medical applications. Chemical and physical synthesis methods are a way to make AuNPs. In any case, the hunt for other more ecologically friendly and cost-effective large-scale technologies, such as environmentally friendly biological processes known as green synthesis, has been gaining interest by worldwide researchers. The international focus on green nanotechnology research has resulted in various nanomaterials being used in environmentally and physiologically acceptable applications. Several advantages over conventional physical and chemical synthesis (simple, one-step approach to synthesize, cost-effectiveness, energy efficiency, and biocompatibility) have drawn scientists’ attention to exploring the green synthesis of AuNPs by exploiting plants’ secondary metabolites. Biogenic approaches, mainly the plant-based synthesis of metal nanoparticles, have been chosen as the ideal strategy due to their environmental and in vivo safety, as well as their ease of synthesis. In this review, we reviewed the use of green synthesized AuNPs in the treatment of cancer by utilizing phytochemicals found in plant extracts. This article reviews plant-based methods for producing AuNPs, characterization methods of synthesized AuNPs, and discusses their physiochemical properties. This study also discusses recent breakthroughs and achievements in using green synthesized AuNPs in cancer treatment and different mechanisms of action, such as reactive oxygen species (ROS), mediated mitochondrial dysfunction and caspase activation, leading to apoptosis, etc., for their anticancer and cytotoxic effects. Understanding the mechanisms underlying AuNPs therapeutic efficacy will aid in developing personalized medicines and treatments for cancer as a potential cancer therapeutic strategy.