In vitro suppression of oral squamous cell carcinoma growth by ultrasound-mediated delivery of curcumin microemulsions

Exploring the therapeutic potential of lipid-based nanoparticles in the management of oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is a highly malignant and invasive tumor with significant mortality and morbidity. Current treatment modalities such as surgery, radiotherapy, and chemotherapy encounter significant limitations, such as poor targeting, systemic toxicity, and drug resistance. There is an urgent need for novel therapeutic strategies that offer targeted delivery, enhanced efficacy, and reduced side effects. The advent of lipid-based nanoparticles (LNPs) offers a promising tool for OSCC therapy, potentially overcoming the limitations of current therapeutic approaches. LNPs are composed of biodegradable and biocompatible lipids, which minimize the risk of toxicity and adverse effects. LNPs can encapsulate hydrophobic drugs, improving their solubility and stability in the biological environment, thereby enhancing their bioavailability. LNPs demonstrate significantly higher ability to encapsulate lipophilic drugs than other nanoparticle types. LNPs offer excellent storage stability, minimal drug leakage, and controlled drug release, making them highly effective nanoplatforms for the delivery of chemotherapeutic agents. Additionally, LNPs can be modified by complexing them with specific target ligands on their surface. This surface modification allows the active targeting of LNPs to the tumors in addition to the passive targeting mechanism. Furthermore, the PEGylation of LNPs improves their hydrophilicity and enhances their biological half-life by reducing clearance by the reticuloendothelial system. This review aims to discuss current treatment approaches and their limitations, as well as recent advancements in LNPs for better management of OSCC.

Therapeutic potential of curcumin and its nanoformulations for treating oral cancer

The global incidence of oral cancer has steadily increased in recent years and is associated with high morbidity and mortality. Oral cancer is the most common cancer in the head and neck region, and is predominantly of epithelial origin (i.e. squamous cell carcinoma). Oral cancer treatment modalities mainly include surgery with or without radiotherapy and chemotherapy. Though proven effective, chemotherapy has significant adverse effects with possibilities of tumor resistance to anticancer drugs and recurrence. Thus, there is an imperative need to identify suitable anticancer therapies that are highly precise with minimal side effects and to make oral cancer treatment effective and safer. Among the available adjuvant therapies is curcumin, a plant polyphenol isolated from the rhizome of the turmeric plant Curcuma longa. Curcumin has been demonstrated to have anti-infectious, antioxidant, anti-inflammatory, and anticarcinogenic properties. Curcumin has poor bioavailability, which has been overcome by its various analogues and nanoformulations, such as nanoparticles, liposome complexes, micelles, and phospholipid complexes. Studies have shown that the anticancer effects of curcumin are mediated by its action on multiple molecular targets, including activator protein 1, protein kinase B (Akt), nuclear factor κ-light-chain-enhancer of activated B cells, mitogen-activated protein kinase, epidermal growth factor receptor (EGFR) expression, and EGFR downstream signaling pathways. These targets play important roles in oral cancer pathogenesis, thereby making curcumin a promising adjuvant treatment modality. This review aims to summarize the different novel formulations of curcumin and their role in the treatment of oral cancer.

Curcumin Formulations for Better Bioavailability: What We Learned from Clinical Trials Thus Far?

Curcumin has been credited with a wide spectrum of pharmacological properties for the prevention and treatment of several chronic diseases such as arthritis, autoimmune diseases, cancer, cardiovascular diseases, diabetes, hemoglobinopathies, hypertension, infectious diseases, inflammation, metabolic syndrome, neurological diseases, obesity, and skin diseases. However, due to its weak solubility and bioavailability, it has limited potential as an oral medication. Numerous factors including low water solubility, poor intestinal permeability, instability at alkaline pH, and fast metabolism contribute to curcumin's limited oral bioavailability. In order to improve its oral bioavailability, different formulation techniques such as coadministration with piperine, incorporation into micelles, micro/nanoemulsions, nanoparticles, liposomes, solid dispersions, spray drying, and noncovalent complex formation with galactomannosides have been investigated with in vitro cell culture models, in vivo animal models, and humans. In the current study, we extensively reviewed clinical trials on various generations of curcumin formulations and their safety and efficacy in the treatment of many diseases. We also summarized the dose, duration, and mechanism of action of these formulations. We have also critically reviewed the advantages and limitations of each of these formulations compared to various placebo and/or available standard care therapies for these ailments. The highlighted integrative concept embodied in the development of next-generation formulations helps to minimize bioavailability and safety issues with least or no adverse side effects and the provisional new dimensions presented in this direction may add value in the prevention and cure of complex chronic diseases.

Thermosensitive and mucoadhesive hydrogel containing curcumin-loaded lipid-core nanocapsules coated with chitosan for the treatment of oral squamous cell carcinoma

Buccal drug administration may be chosen as a medication route to treat various diseases for local or systemic effects. This study proposes the development of a thermosensitive hydrogel containing curcumin-loaded lipid-core nanocapsules coated with chitosan to increase mucoadhesion, circumventing several limitations of this route of administration. Hydroxypropylmethylcellulose and Poloxamer^® 407 were incorporated for hydrogel production. Physicochemical characterization parameters, such as particle size distribution, mean diameter, polydispersity index, zeta potential, and morphology, were analyzed. Spherical homogeneous particles were obtained with average diameter, of 173 ± 22 nm for LNCc (curcumin lipid-core nanocapsules) and 179 ± 48 nm for CLNCc (chitosan-curcumin lipid-core nanocapsules). A PDI equal to 0.09 ± 0.02 for LNCc and 0.26 ± 0.01 for CLNCc confirmed homogeneity. Tensile analysis and washability test on porcine buccal mucosa indicated higher mucoadhesion for hydrogels in comparison to the nanocapsules in suspension, remaining on the mucous membrane up to 8 h (10.92 ± 3.95 µg of curcumin washed for H-LNCc and 28.41 ± 24.47 µg for H-CLNCc) versus the latter, which remained washed on the membrane for 90 min only (62.60 ± 4.72 µg for LNCc and 52.08 ± 1.63 µg for CLNCc). The irritant potential (IR) of the formulations was evaluated by the hen's egg chorioallantoic membrane test (HET-CAM), with no irritation phenomena observed. Formulations were tested for their efficacy in an in vitro model against oral squamous cancer cell line, showing a significant reduction in cell viability on all tested groups. These findings demonstrated that the proposed nanosystem is mucoadhesive and has potential to deliver buccal treatments.

DNA Based and Stimuli-Responsive Smart Nanocarrier for Diagnosis and Treatment of Cancer: Applications and Challenges

The rapid development of multidrug co-delivery and nano-medicines has made spontaneous progress in tumor treatment and diagnosis. DNA is a unique biological molecule that can be tailored and molded into various nanostructures. The addition of ligands or stimuli-responsive elements enables DNA nanostructures to mediate highly targeted drug delivery to the cancer cells. Smart DNA nanostructures, owing to their various shapes, sizes, geometry, sequences, and characteristics, have various modes of cellular internalization and final disposition. On the other hand, functionalized DNA nanocarriers have specific receptor-mediated uptake, and most of these ligand anchored nanostructures able to escape lysosomal degradation. DNA-based and stimuli responsive nano-carrier systems are the latest advancement in cancer targeting. The data exploration from various studies demonstrated that the DNA nanostructure and stimuli responsive drug delivery systems are perfect tools to overcome the problems existing in the cancer treatment including toxicity and compromised drug efficacy. In this light, the review summarized the insights about various types of DNA nanostructures and stimuli responsive nanocarrier systems applications for diagnosis and treatment of cancer.

Novel Gel Microemulsion as Topical Drug Delivery System for Curcumin in Dermatocosmetics

Gel microemulsion combines the advantages of the microemulsion, which can encapsulate, protect and deliver large quantities of active ingredients, and the gel, which is so appreciated in the cosmetic industry. This study aimed to develop and characterize new gel microemulsions suitable for topical cosmetic applications, using grape seed oil as the oily phase, which is often employed in pharmaceuticals, especially in cosmetics. The optimized microemulsion was formulated using Tween 80 and Plurol^® Diisostearique CG as a surfactant mix and ethanol as a co-solvent. Three different water-soluble polymers were selected in order to increase the viscosity of the microemulsion: Carbopol^® 980 NF, chitosan, and sodium hyaluronate salt. All used ingredients are safe, biocompatible and biodegradable. Curcumin was chosen as a model drug. The obtained systems were physico-chemically characterized by means of electrical conductivity, dynamic light scattering, polarized microscopy and rheometric measurements. Evaluation of the cytotoxicity was accomplished by MTT assay. In the final phase of the study, the release behavior of Curcumin from the optimized microemulsion and two gel microemulsions was evaluated. Additionally, mathematical models were applied to establish the kinetic release mechanism. The obtained gel microemulsions could be effective systems for incorporation and controlled release of the hydrophobic active ingredients.

The Antioxidant Capacity In Vitro and In Vivo of Polysaccharides From Bergenia emeiensis

Polysaccharides from Bergenia emeiensis (PBE) showed a robust antioxidant ability on scavenging free radicals in vitro. However, the further antioxidant potential in cell level and in vivo was still unknown. Therefore, in this present study, the protective effect of PBE on human cervical carcinoma cell (Hela) cells and Caenorhabditis elegans against oxidative stress was evaluated. The results showed PBE could reduce the reactive oxygen species (ROS) level in Hela cells and promote the mitochondrial membrane potential. Then, the cell apoptosis was reduced. Moreover, PBE could enhance the survival of C. elegans under thermal stress to 13.44%, and significantly reduce the ROS level, which was connected with the overexpression of sod-3 and the increased nuclear localization of daf-16 transcription factor. Therefore, PBE exhibited a strong antioxidant capacity in the cellular level and for a whole organism. Thus, polysaccharides from B. emeiensis have natural potential to be a safe antioxidant.

GHz Ultrasonic Chip-Scale Device Induces Ion Channel Stimulation in Human Neural Cells

Emergent trends in the device development for neural prosthetics have focused on establishing stimulus localization, improving longevity through immune compatibility, reducing energy re-quirements, and embedding active control in the devices. Ultrasound stimulation can single-handedly address several of these challenges. Ultrasonic stimulus of neurons has been studied extensively from 100 kHz to 10 MHz, with high penetration but less localization. In this paper, a chip-scale device consisting of piezoelectric Aluminum Nitride ultrasonic transducers was engineered to deliver gigahertz (GHz) ultrasonic stimulus to the human neural cells. These devices provide a path towards complementary metal oxide semiconductor (CMOS) integration towards fully controllable neural devices. At GHz frequencies, ultrasonic wavelengths in water are a few microns and have an absorption depth of 10-20 µm. This confinement of energy can be used to control stimulation volume within a single neuron. This paper is the first proof-of-concept study to demonstrate that GHz ultrasound can stimulate neurons in vitro. By utilizing optical calcium imaging, which records calcium ion flux indicating occurrence of an action potential, this paper demonstrates that an application of a nontoxic dosage of GHz ultrasonic waves [Formula: see text] caused an average normalized fluorescence intensity recordings >1.40 for the calcium transients. Electrical effects due to chip-scale ultrasound delivery was discounted as the sole mechanism in stimulation, with effects tested at α = 0.01 statistical significance amongst all intensities and con-trol groups. Ionic transients recorded optically were confirmed to be mediated by ion channels and experimental data suggests an insignificant thermal contributions to stimulation, with a predicted increase of 0.03 ^oC for [Formula: see text] This paper paves the experimental framework to further explore chip-scale axon and neuron specific neural stimulation, with future applications in neural prosthetics, chip scale neural engineering, and extensions to different tissue and cell types.

Nanomedicine, an emerging therapeutic strategy for oral cancer therapy

Oral cavity and oropharyngeal carcinomas (oral cancer) represents a significant cause of morbidity and mortality. Despite efforts in improving early diagnosis and treatment, the 5-year survival rate of advanced stage of the disease is less than 63%. The field of nanomedicine has offered promising diagnostic and therapeutic advances in cancer. Indeed, several platforms have been clinically approved for cancer therapy, while other promising systems are undergoing exploration in clinical trials. With its ability to deliver drugs, nucleic acids, and MRI contrast agents with high efficiency, nanomedicine platforms offer the potential to improve drug efficacy and tolerability. The aim of the present mini-review is to summarize the current preclinical status of nanotechnology systems for oral cancer therapy. The nanoplatforms for delivery of chemopreventive agents presented herein resulted in significantly higher anti-tumor activity than free forms of the drug, even against a chemo-resistant cell line. Impressive results have also been obtained using nanoparticles to deliver chemotherapeutics, resulting in reduced toxicity both in vitro and in vivo. Nanoparticles have also led to improvements in efficacy of photodynamic therapies through the development of targeted magnetic nanoparticles. Finally, gene therapy using nanoparticles demonstrated promising results specifically with regards to inhibition of gene expression. Of the few in vivo studies that have been reported, many of these used animal models with several limitations, which will be discussed herein. Lastly, we will discuss several future perspectives in oral cancer nanoparticle-based therapy and the development of appropriate animal models, distinguishing between oral cavity and oropharyngeal carcinoma.

Future trends and emerging issues for nanodelivery systems in oral and oropharyngeal cancer

Oral cancer is a prevalent cancer type on a global scale, whose traditional treatment strategies have several drawbacks that could in the near future be overcome through the development of novel therapeutic and prognostic strategies. Nanotechnology provides an alternative to traditional therapy that leads to enhanced efficiency and less toxicity. Various nanosystems have been developed for the treatment of oral cancer, including polymeric, metallic, and lipid-based formulations that incorporate chemotherapeutics, natural compounds, siRNA, or other molecules. This review summarizes the main benefits of using these nanosystems, in parallel with a particular focus on the issues encountered in medical practice. These novel strategies have provided encouraging results in both in vitro and in vivo studies, but few have entered clinical trials. The use of nanosystems in oral cancer has the potential of becoming a valid therapeutic option for patients suffering from this malignancy, considering that clinical trials have already been completed and others are currently being developed.

Potential Compounds for Oral Cancer Treatment: Resveratrol, Nimbolide, Lovastatin, Bortezomib, Vorinostat, Berberine, Pterostilbene, Deguelin, Andrographolide, and Colchicine

Oral cancer is one of the main causes of cancer-related deaths in South-Asian countries. There are very limited treatment options available for oral cancer. Research endeavors focused on discovery and development of novel therapies for oral cancer, is necessary to control the ever rising oral cancer related mortalities. We mined the large pool of compounds from the publicly available compound databases, to identify potential therapeutic compounds for oral cancer. Over 84 million compounds were screened for the possible anti-cancer activity by custom build SVM classifier. The molecular targets of the predicted anti-cancer compounds were mined from reliable sources like experimental bioassays studies associated with the compound, and from protein-compound interaction databases. Therapeutic compounds from DrugBank, and a list of natural anti-cancer compounds derived from literature mining of published studies, were used for building partial least squares regression model. The regression model thus built, was used for the estimation of oral cancer specific weights based on the molecular targets. These weights were used to compute scores for screening the predicted anti-cancer compounds for their potential to treat oral cancer. The list of potential compounds was annotated with corresponding physicochemical properties, cancer specific bioactivity evidences, and literature evidences. In all, 288 compounds with the potential to treat oral cancer were identified in the current study. The majority of the compounds in this list are natural products, which are well-tolerated and have minimal side-effects compared to the synthetic counterparts. Some of the potential therapeutic compounds identified in the current study are resveratrol, nimbolide, lovastatin, bortezomib, vorinostat, berberine, pterostilbene, deguelin, andrographolide, and colchicine.

Herbal mouthwash containing extracts of Baccharis dracunculifolia as agent for the control of biofilm: clinical evaluation in humans

Baccharis dracunculifolia DC (Asteraceae), popularly known as “alecrim-do-campo,” is largely distributed in South America, is shown to exhibit protective actions against gastric ulcers, has anti-inflammatory properties, and is hepatoprotective. Several essential oils obtained from Baccharis species possess biological activities, such as antimicrobial and antivirus activities. This randomized controlled trial evaluated the efficacy of B. dracunculifolia in the reduction of dental biofilm, comparing this natural product with other mouthwashes already known in the dental market. In measuring the time after use of mouthwash (t = 1), there was no difference between products (P = 0.602); that is, subjects in the study had a similar PI after the first use. After one week (t = 2), there was no difference between the four products evaluated (P = 0.674), so, all research individuals completed the study with a similar reduction in dental biofilm between themselves but it was different from initial state (Friedman test). It is possible to conclude that B. dracunculifolia had the same efficiency of the materials used to oral hygiene in reduction of dental plaque and, consequently, prevention of dental caries. Thus, we can consider B. dracunculifolia as a good candidate for new material to be implemented in dental care.