Can Compounds of Natural Origin Be Important in Chemoprevention? Anticancer Properties of Quercetin, Resveratrol, and Curcumin-A Comprehensive Review

Malignant tumors are the second most common cause of death worldwide. More attention is being paid to the link between the body's impaired oxidoreductive balance and cancer incidence. Much attention is being paid to polyphenols derived from plants, as one of their properties is an antioxidant character: the ability to eliminate reactive oxygen and nitrogen species, chelate specific metal ions, modulate signaling pathways affecting inflammation, and raise the level and activity of antioxidant enzymes while lowering those with oxidative effects. The following three compounds, resveratrol, quercetin, and curcumin, are polyphenols modulating multiple molecular targets, or increasing pro-apoptotic protein expression levels and decreasing anti-apoptotic protein expression levels. Experiments conducted in vitro and in vivo on animals and humans suggest using them as chemopreventive agents based on antioxidant properties. The advantage of these natural polyphenols is low toxicity and weak adverse effects at higher doses. However, the compounds discussed are characterized by low bioavailability and solubility, which may make achieving the blood concentrations needed for the desired effect challenging. The solution may lie in derivatives of naturally occurring polyphenols subjected to structural modifications that enhance their beneficial effects or work on implementing new ways of delivering antioxidants that improve their solubility and bioavailability.

Design and Synthesis of Novel Near-Infrared Fluorescence Probes Based on an Open Conformation of a Cytochrome P450 1B1 Complex for Molecular Imaging of Colorectal Tumors

Cytochrome P450 1B1 (CYP1B1) is induced during the early stage of cancer and is universally overexpressed in tumors. Thus, it was considered as a potential biomarker for the monitoring of cancer. In this study, we designed and synthesized CYP1B1-targeted near-infrared (NIR) fluorescence molecular probes based on the latest reported open conformation of the CYP1B1-α-naphthoflavone (ANF) complex. According to the architecture of the open channel, we introduced linkers and a Cy5.5 fragment at the 5' position of ANF derivatives with strong CYP1B1 inhibitory activity to obtain probes 19-21. Then, in vitro cell-based studies showed that the probes could be enriched in tumor cells by binding to CYP1B1. During in vivo and ex vivo imaging in a xenograft mouse model, probe 19 with the best binding affinity was proven to be able to identify tumor sites in both fluorescence imaging and photoacoustic imaging modes.

Targeting Cytochrome P450 Enzymes in Ovarian Cancers: New Approaches to Tumor-Selective Intervention

Over the past decade, there have been significant developments in treatment for ovarian cancer, yet the lack of targeted therapy with few side effects still represents a major issue. The cytochrome P450 (CYP) enzyme family plays a vital role in the tumorigenesis process and metabolism of drugs and has a negative impact on therapy outcomes. Gaining more insight into CYP expression is crucial to understanding the pathophysiology of ovarian cancer since many isoforms are essential to the metabolism of xenobiotics and steroid hormones, which drive the disease's development. To the best of our knowledge, no review articles have documented the intratumoral expression of CYPs and their implications in ovarian cancer. Therefore, the purpose of this review is to provide a clear understanding of differential CYP expression in ovarian cancer and its implications for the prognosis of ovarian cancer patients, together with the effects of CYP polymorphisms on chemotherapy metabolism. Finally, we discuss opportunities to exploit metabolic CYP expression for the development of novel therapeutic methods to treat ovarian cancer.

Hydration and Structural Adaptations of the Human CYP1A1, CYP1A2, and CYP1B1 Active Sites by Molecular Dynamics Simulations

Cytochromes CYP1A1, CYP1A2, and CYP1B1, the members of the cytochrome P450 family 1, catalyze the metabolism of endogenous compounds, drugs, and non-drug xenobiotics which include substances involved in the process of carcinogenesis, cancer chemoprevention, and therapy. In the present study, the interactions of three selected polymethoxy-trans-stilbenes, analogs of a bioactive polyphenol trans-resveratrol (3,5,4'-trihydroxy-trans-stilbene) with the binding sites of CYP1 isozymes were investigated with molecular dynamics (MD) simulations. The most pronounced structural changes in the CYP1 binding sites were observed in two substrate recognition sites (SRS): SRS2 (helix F) and SRS3 (helix G). MD simulations show that the number and position of water molecules occurring in CYP1 APO and in the structures complexed with ligands are diverse. The presence of water in binding sites results in the formation of water-protein, water-ligand, and bridging ligand-water-protein hydrogen bonds. Analysis of the solvent and substrate channels opening during the MD simulation showed significant differences between cytochromes in relation to the solvent channel and the substrate channels 2c, 2ac, and 2f. The results of this investigation lead to a deeper understanding of the molecular processes that occur in the CYP1 binding sites and may be useful for further molecular studies of CYP1 functions.

Understanding and targeting resistance mechanisms in cancer

Resistance to cancer therapies has been a commonly observed phenomenon in clinical practice, which is one of the major causes of treatment failure and poor patient survival. The reduced responsiveness of cancer cells is a multifaceted phenomenon that can arise from genetic, epigenetic, and microenvironmental factors. Various mechanisms have been discovered and extensively studied, including drug inactivation, reduced intracellular drug accumulation by reduced uptake or increased efflux, drug target alteration, activation of compensatory pathways for cell survival, regulation of DNA repair and cell death, tumor plasticity, and the regulation from tumor microenvironments (TMEs). To overcome cancer resistance, a variety of strategies have been proposed, which are designed to enhance the effectiveness of cancer treatment or reduce drug resistance. These include identifying biomarkers that can predict drug response and resistance, identifying new targets, developing new targeted drugs, combination therapies targeting multiple signaling pathways, and modulating the TME. The present article focuses on the different mechanisms of drug resistance in cancer and the corresponding tackling approaches with recent updates. Perspectives on polytherapy targeting multiple resistance mechanisms, novel nanoparticle delivery systems, and advanced drug design tools for overcoming resistance are also reviewed.

Structure-Based Drug Design and Synthesis of Novel N-Aryl-2,4-bithiazole-2-amine CYP1B1-Selective Inhibitors in Overcoming Taxol Resistance in A549 Cells

As a promising therapeutic target for cancer, CYP1B1 is overexpressed in Taxol-resistant A549 cells; however, its role in drug resistance still remains unclear. Bioinformatic analysis data indicated that CYP1B1 was closely correlated with AKT/ERK1/2 and focal adhesion pathways, thereby playing an important role in Taxol resistance and cancer migration/invasion. Along similar lines, the AhR agonist 7,12-dimethylbenz[a]anthracene (DMBA) enhanced Taxol resistance and promoted migration/invasion of A549 and H460 cells likely stemming from CYP1B1 upregulation. Moreover, 83 novel N-aryl-2,4-bithiazole-2-amine CYP1B1-selective inhibitors were designed and synthesized to verify the role of CYP1B1 in Taxol-resistant A549 cells. Impressively, the most potent and selective one, namely, 77, remarkably inhibited AKT/ERK1/2 and FAK/SRC pathways and thereby reversed Taxol resistance as well as inhibited both migration and invasion of A549/Taxol cells. Collectively, this study not only displayed the role of CYP1B1 in Taxol resistance and cancer migration/invasion but also helped unlock the CYP1B1-oriented anticancer discovery.

Computational Investigation of Ligand Binding of Flavonoids in Cytochrome P450 Receptors

AIM

The cytochrome P450 enzymes play a significant role in regulating cellular and physiological processes by activating endogenous compounds. They also play an essential role in the detoxification process of xenobiotics. Flavonoids belong to a class of polyphenols found in food, such as vegetables, red wine, beer, and fruits, which modulate biological functions in the body.

METHODS

The inhibition of CYP1A1 and CYP1B1 using nutritional sources has been reported as a strategy for cancer prevention. This study investigated the interactions of selected flavonoids binding to the cytochrome P450 enzymes (CYP1A1 and CYP1B1) and their ADMET properties in silico. From docking studies, our findings showed flavonoids, isorhamnetin and pedalitin, to have the strongest binding energies in the crystal structures 6DWM and 6IQ5.

RESULTS

The amino acid residues Asp 313 and Phe 224 in 6DWM interacted with all the ligands investigated, and Ala 330 in 6IQ5 interacted with all the ligands examined. The ligands did not violate any drug-likeness parameters.

CONCLUSION

These data suggest roles for isorhamnetin and pedalitin as potential precursors for natural product- derived therapies.

Association of Leu432Val (rs1056836) polymorphism of the CYP1B1 gene with lipid profile in hypertensive Slovak women

Leu432Val (rs1056836) polymorphism of the CYP1B1 gene was examined in relationship with lipid profile in hypertensive Slovak women according to their menopausal status. The entire study sample comprised 255 women suffering from hypertension aged from 39 to 65 years who were recruited from different localities in the western, southern, and middle parts of Slovakia. The participants provided a saliva or blood sample for DNA genotyping and a blood sample for biochemical analysis. The Leu432Val genotypes demonstrated statistically significant associations with all monitored atherogenic indices – total cholesterol-to-HDL-Cholesterol (AI1), Non-HDL-Cholesterol (AI2), LDL-Cholesterol-to-HDL-Cholesterol (AI3), and the logarithm of the ratio of plasma concentration of triglycerides to HDL-cholesterol (AIP log) in hypertensive pre/perimenopausal women. The mean values were significantly lower in women carrying the Val/Val genotype. In early postmenopausal hypertensive women the Leu432Val genotypes were statistically significant and associated with LDL-cholesterol (LDL-C) and AI2. The mean values of LDL-C and AI2 were significantly lower in women carrying the Leu/Leu genotype. In conclusion, the Leu432Val polymorphism may be associated with the atherogenic indices and LDL-C in hypertensive women.

Possible Role of Cytochrome P450 1B1 in the Mechanism of Gemcitabine Resistance in Pancreatic Cancer

Patient-derived xenograft models reportedly represent original tumor morphology and gene mutation profiles. In addition, patient-derived xenografts are expected to recapitulate the parental tumor drug responses. In this study, we analyzed the pathways involved in gemcitabine resistance using patient-derived xenograft models of pancreatic cancer. The patient-derived xenograft models were established using samples from patients with pancreatic cancer. The models were treated with gemcitabine to better understand the mechanism of resistance to this anti-cancer drug. We performed comparative gene analysis through the next-generation sequencing of tumor tissues from gemcitabine-treated or non-treated patient-derived xenograft mice and gene set enrichment analysis to analyze mRNA profiling data. Pathway analysis of gemcitabine-treated patient-derived xenografts disclosed the upregulation of multiple gene sets and identified several specific gene pathways that could potentially be related to gemcitabine resistance in pancreatic cancer. Further, we conducted an in vitro analysis to validate these results. The mRNA expression of cytochrome P450 1B1 and cytochrome P450 2A6 was upregulated in a concentration-dependent manner following gemcitabine treatment. Moreover, the sensitivity to gemcitabine increased, and viable cells were decreased by the cytochrome P450 1B1 inhibitor, indicating that the cytochrome P450 1B1 pathway may be related to gemcitabine resistance in pancreatic cancer.