Quercetin Therapy for Selected Patients with PIM1 Kinase-Positive Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma: A Pilot Study

Bioactive Phytoconstituents and Their Therapeutic Potentials in the Treatment of Haematological Cancers: A Review

Haematological (blood) cancers are the cancers of the blood and lymphoid forming tissues which represents approximately 10% of all cancers. It has been reported that approximately 60% of all blood cancers are incurable. Despite substantial improvement in access to detection/diagnosis, chemotherapy and bone marrow transplantation, there is still high recurrence and unpredictable but clearly defined relapses indicating that effective therapies are still lacking. Over the past two decades, medicinal plants and their biologically active compounds are being used as potential remedies and alternative therapies for the treatment of cancer. This is due to their anti-oxidant, anti-inflammatory, anti-mutagenic, anti-angiogenic, anti-cancer activities and negligible side effects. These bioactive compounds have the capacity to reduce proliferation of haematological cancers via various mechanisms such as promoting apoptosis, transcription regulation, inhibition of signalling pathways, downregulating receptors and blocking cell cycle. This review study highlights the mechanistic and beneficial effects of nine bioactive compounds (quercetin, ursolic acid, fisetin, resveratrol, epigallocatechin gallate, curcumin, gambogic acid, butein and celastrol) as potential remedies for chemoprevention of haematological cancers. The study provides useful insights on the effectiveness of the use of bioactive compounds from plants for chemoprevention of haematological cancers.

Bioactive Compounds from Kalanchoe Genus Potentially Useful for the Development of New Drugs

The genus Kalanchoe Adans. (Crassulaceae) is native to Madagascar and comprises 145 species, being naturalized in the tropics and cultivated worldwide. In addition to having ornamental value, several Kalanchoe species are commonly used in popular medicine for the treatment of inflammatory conditions, wounds, gastric ulcers, and other diseases. The great importance of the genus is reflected on its acknowledgment by traditional and alternative health systems and organizations, as well as on the growing number of papers reporting pharmacological properties of extracts and isolated compounds from Kalanchoe. Among these properties, we highlight anti-inflammatory, antitumor, wound healing, antiulcer, and muscle relaxing properties. These activities are attributed mostly to flavonoids and bufadienolides, the main secondary metabolites reported in Kalanchoe extracts. While bufadienolides are generally related to cytotoxic and muscle relaxing activities, flavonoids are commonly reported as anti-inflammatory and wound healing agents. This review provides up to date information and perspectives on bioactive compounds from the Kalanchoe genus that are potentially useful for the development of new drugs. It includes not only a discussion on the advantages of the Kalanchoe species as source of bioactive compounds, but also the gaps, opportunities, and challenges to translate the acquired knowledge into innovation for drug development.

Polyphenols: Chemoprevention and therapeutic potentials in hematological malignancies

Polyphenols are one of the largest plant-derived natural product and they play an important role in plants' defense as well as in human health and disease. A number of them are pleiotropic molecules and have been shown to regulate signaling pathways, immune response and cell growth and proliferation which all play a role in cancer development. Hematological malignancies on the other hand, are cancers of the blood. While current therapies are efficacious, they are usually expensive and with unwanted side effects. Thus, the search for newer less toxic agents. Polyphenols have been reported to possess antineoplastic properties which include cell cycle arrest, and apoptosis via multiple mechanisms. They also have immunomodulatory activities where they enhance T cell activation and suppress regulatory T cells. They carry out these actions through such pathways as PI3K/Akt/mTOR and the kynurenine. They can also reverse cancer resistance to chemotherapy agents. In this review, i look at some of the molecular mechanism of action of polyphenols and their potential roles as therapeutic agents in hematological malignancies. Here i discuss their anti-proliferative and anti-neoplastic activities especially their abilities modulate signaling pathways as well as immune response in hematological malignancies. I also looked at clinical studies done mainly in the last 10-15 years on various polyphenol combination and how they enhance synergism. I recommend that further preclinical and clinical studies be carried out to ensure safety and efficacy before polyphenol therapies be officially moved to the clinics.

Conjunctival chronic lymphocytic leukemia presenting as bilateral chronic conjunctivitis

Purpose

This report describes a case of conjunctival chronic lymphocytic leukemia (CLL) in a 73 year-old female with a prior history of CLL thought to be in remission who presented with bilateral chronic conjunctivitis.

Observation

Examination revealed bilateral conjunctival injection, mildly purulent discharge, and the presence of large follicle-like lesions involving the bilateral superior and inferior palpebral conjunctiva. Conjunctival cultures grew Corynebacterium species. The patient was treated with topical antibiotics and steroids which improved the conjunctival injection and discharge, but the follicle-like lesions persisted. A conjunctival biopsy was performed and was consistent with the diagnosis of chronic lymphocytic leukemia. Fundoscopic exam did not demonstrate posterior uveal or retinal involvement. She was referred to her oncologist for further evaluation and management. Marked clinical improvement was noted after starting treatment with ibrutinib.

Conclusions and importance

This case demonstrates a rare ocular manifestation of the most common form of leukemia. It happened to present with common, nonspecific symptoms of eye redness, discharge, and follicular reaction consistent with a bilateral chronic conjunctivitis. Clinical appearance and symptoms improved with topical steroids and eventually resolved with systemic bruton kinase inhibitor therapy.

Functional Depletion of HSP72 by siRNA and Quercetin Enhances Vorinostat-Induced Apoptosis in an HSP72-Overexpressing Cutaneous T-Cell Lymphoma Cell Line, Hut78

Histone deacetylase inhibitors (HDACis) are one of the therapeutic options for cutaneous T-cell lymphoma (CTCL), but they have limited effects. We previously demonstrated that HSP72 overexpression is associated with chemoresistance to HDACis in lymphoma cells. The purpose of this study was to investigate whether the functional depletion of HSP72 enhances the effect of the HDACi vorinostat. First, we established a stable HSP72-knockdown CTCL cell line and confirmed the influence of HSP72 reduction on the antitumor effects of vorinostat. Next, we studied the effect of quercetin, an inhibitor of HSP72, on the antineoplastic effects of vorinostat. In five CTCL cell lines examined, HSP72 expression was highest in Hut78 cells, and HSP72 knockdown enhanced vorinostat-induced apoptosis in these cells. Low-dose quercetin reduced HSP72 expression, increased HDAC activity, and enhanced vorinostat-induced suppression of Hut78 cell proliferation. A single low dose of quercetin induced G2 arrest and only slightly increased the sub-G1 cell fraction. Quercetin also significantly enhanced vorinostat-induced apoptosis, caspase-3, caspase-8, and caspase-9 activity, and the loss of mitochondrial membrane potential. HSP72 knockdown enhanced vorinostat-induced apoptosis in an HSP72-overexpressing CTCL cell line, and thus, quercetin may be a suitable candidate for combination therapy with vorinostat in clinical settings.

Therapeutic Potential of Quercetin: New Insights and Perspectives for Human Health

Quercetin (Que) and its derivatives are naturally occurring phytochemicals with promising bioactive effects. The antidiabetic, anti-inflammatory, antioxidant, antimicrobial, anti-Alzheimer's, antiarthritic, cardiovascular, and wound-healing effects of Que have been extensively investigated, as well as its anticancer activity against different cancer cell lines has been recently reported. Que and its derivatives are found predominantly in the Western diet, and people might benefit from their protective effect just by taking them via diets or as a food supplement. Bioavailability-related drug-delivery systems of Que have also been markedly exploited, and Que nanoparticles appear as a promising platform to enhance their bioavailability. The present review aims to provide a brief overview of the therapeutic effects, new insights, and upcoming perspectives of Que.

PIM1, CYP1B1, and HSPA2 Targeted by Quercetin Play Important Roles in Osteoarthritis Treatment by Achyranthes bidentata

Aim

Achyranthes bidentata is one of the most commonly used Chinese herbal medicines (CHM) that is currently considered for the treatment of osteoarthritis. The purpose of this study was to reveal the mechanism of Achyranthes bidentata in osteoarthritis treatment based on the network pharmacology.

Methods

The effective components of Achyranthes bidentata were firstly screened out from the TCMSP database with ADME property parameters. Then, osteoarthritis-related proteins targeted by the effective components were predicted based on the DrugBank and CTD databases. Subsequently, enrichment analysis and interaction network between targets of effective components and pathways were also studied. In addition, the differentially expressed genes (DEGs) of GSE55457 were used for validation of the osteoarthritis-related target proteins. Finally, the effective components-target molecular docking models were predicted.

Results

A total of 10 effective components were identified, of which kaempferol and quercetin had 1 and 29 targets, respectively. There were 26 target proteins of quercetin related to the osteoarthritis. These targets were mainly enriched in mitochondrial ATP synthesis coupled proton transport, cellular response to estradiol stimulus, and nitric oxide biosynthetic process. In addition, there were three common proteins, PIM1, CYP1B1, and HSPA2 based on the DEGs of GSE55457, which were considered as the key targeted proteins of the quercetin.

Conclusion

The docking of PIM1-quercetin, CYP1B1-quercetin, and HSPA2-quercetin may play important roles during the treatment of osteoarthritis by Achyranthes bidentata.

Large-Scale Target Identification of Herbal Medicine Using a Reverse Docking Approach

Herbal medicine has been used to countermine various diseases for centuries. However, most of the therapeutic targets underlying herbal therapy remain unclear, which largely slow down the novel drug discovery process from natural products. In this study, we developed a novel computational pipeline for assisting de novo identification of protein targets for herbal ingredients. The pipeline involves pharmacophore comparison and reverse ligand-protein docking simulation in a high throughput manner. We evaluated the pipeline using three traditional Chinese medicine ingredients such as acteoside, quercetin, and epigallocatechin gallate as examples. A majority of current known targets of these ingredients were successfully identified by the pipeline. Structural comparative analyses confirmed that the predicted ligand-target interactions used the same binding pockets and binding modes as those of known ligand-target interactions. Furthermore, we illustrated the mechanism of actions of the ingredients by constructing the pharmacological networks on the basis of the predicted target profiles. In summary, we proposed an efficient and economic option for large-scale target exploration in the herb study. This pipeline will be particularly valuable in aiding precise drug discovery and drug repurposing from natural products.

Cholate-modified polymer-lipid hybrid nanoparticles for oral delivery of quercetin to potentiate the antileukemic effect

Background: Quercetin (QUE) shows a potential antileukemic activity, but possesses poor solubility and low bioavailability. Purpose: This article explored the bile salt transport pathway for oral deliver of QUE using cholate-modified polymer-lipid hybrid nanoparticles (cPLNs) aiming to enhance its antileukemic effect. Methods: QUE-loaded cPLNs (QUE-cPLNs) were developed through a nanoprecipitation technique and characterized by particle size, entrapment efficiency (EE), microscopic morphology and in vitro drug release. In vitro cellular uptake and cytotoxicity of QUE-cPLNs were examined on Caco-2 and P388 cells; in vivo pharmacokinetics and antileukemic effect were evaluated using Sprague Dawley rats and leukemic model mice, respectively. Results: The prepared QUE-cPLNs possessed a particle size of 110 nm around with an EE of 96.22%. QUE-cPLNs resulted in significantly enhanced bioavailability of QUE, up to 375.12% relative to the formulation of suspensions. In addition, QUE-cPLNs exhibited excellent cellular uptake and internalization capability compared to cholate-free QUE-PLNs. The in vitro cytotoxic and in vivo antileukemic effects of QUE-cPLNs were also signally superior to free QUE and QUE-PLNs. Conclusion: These findings indicate that cPLNs are a promising nanocarrier able to improve the oral bioavailability and therapeutic index of QUE.