Process optimization and photostability of silymarin nanostructured lipid carriers: effect on UV-irradiated rat skin and SK-MEL 2 cell line

Gel Formulations for Topical Treatment of Skin Cancer: A Review

Skin cancer, with all its variations, is the most common type of cancer worldwide. Chemotherapy by topical application is an attractive strategy because of the ease of application and non-invasiveness. At the same time, the delivery of antineoplastic agents through the skin is difficult because of their challenging physicochemical properties (solubility, ionization, molecular weight, melting point) and the barrier function of the stratum corneum. Various approaches have been applied in order to improve drug penetration, retention, and efficacy. This systematic review aims at identifying the most commonly used techniques for topical drug delivery by means of gel-based topical formulations in skin cancer treatment. The excipients used, the preparation approaches, and the methods characterizing gels are discussed in brief. The safety aspects are also highlighted. The combinatorial formulation of nanocarrier-loaded gels is also reviewed from the perspective of improving drug delivery characteristics. Some limitations and drawbacks in the identified strategies are also outlined and considered within the future scope of topical chemotherapy.

Drug Delivery Systems and Flavonoids: Current Knowledge in Melanoma Treatment and Future Perspectives

Melanoma is an aggressive form of skin cancer with a high prevalence in the population. An early diagnosis is crucial to cure this disease. Still, when this is not possible, combining potent pharmacological agents and effective drug delivery systems is essential to achieve optimal treatment and improve patients' quality of life. Nanotechnology application in biomedical sciences to encapsulate anticancer drugs, including flavonoids, in order to enhance therapeutic efficacy has attracted particular interest. Flavonoids have shown effectiveness against various types of cancers including in melanoma, but they show low aqueous solubility, low stability and very poor oral bioavailability. The utilization of novel drug delivery systems could increase flavonoid bioavailability, thereby potentiating its antitumor effects in melanoma. This review summarizes the potential of different flavonoids in melanoma treatment and the several nanosystems used to improve their biological activity, considering published information that reported improved biological and pharmacological properties of encapsulated flavonoids.

How to Treat Melanoma? The Current Status of Innovative Nanotechnological Strategies and the Role of Minimally Invasive Approaches like PTT and PDT

Melanoma is the most aggressive type of skin cancer, the incidence and mortality of which are increasing worldwide. Its extensive degree of heterogeneity has limited its response to existing therapies. For many years the therapeutic strategies were limited to surgery, radiotherapy, and chemotherapy. Fortunately, advances in knowledge have allowed the development of new therapeutic strategies. Despite the undoubted progress, alternative therapies are still under research. In this context, nanotechnology is also positioned as a strong and promising tool to develop nanosystems that act as drug carriers and/or light absorbents to potentially improve photothermal and photodynamic therapies outcomes. This review describes the latest advances in nanotechnology field in the treatment of melanoma from 2011 to 2022. The challenges in the translation of nanotechnology-based therapies to clinical applications are also discussed. To sum up, great progress has been made in the field of nanotechnology-based therapies, and our understanding in this field has greatly improved. Although few therapies based on nanoparticulate systems have advanced to clinical trials, it is expected that a large number will come into clinical use in the near future. With its high sensitivity, specificity, and multiplexed measurement capacity, it provides great opportunities to improve melanoma treatment, which will ultimately lead to enhanced patient survival rates.

Recapitulation of Evidence of Phytochemical, Pharmacokinetic and Biomedical Application of Silybin

Silymarin is a standardized extract obtained from seeds of Silybum marianum (SM) belonging to the family Asteraceae. It is a flavonolignan complex and consists of various compounds like silybin A silybin B, isosilybin A, isosilybin B, silydianin, silychristin and isosilychristin. Silybin is the major active component present in 60-70% of the silymarin extract. It has been used traditionally for the treatment of various liver disorders like cirrhosis, jaundice, and hepatitis. Silymarin possesses antioxidant and anti-inflammatory properties and is responsible for its antitumor activity. Other than hepatoprotective effect SM also possesses renoprotective, anti-diabetic, neuroprotective, hypolipidemic, anti-atherosclerosis and cardioprotective effects. Rather antimicrobial property of silymarin was observed against specific microbes, fungi, and viruses. This manuscript covered recent preclinical and clinical evidence of specific components silybin, responsible for its efficacy and about clinical studies has been conducted so far, which proven it's safety and offers mild effect like nausea, diarrhea and bloating. This review specifically focused on recent updates on its active components therapeutic applications against complicated ailments not covered in earlier reports.

Phytosomes as Innovative Delivery Systems for Phytochemicals: A Comprehensive Review of Literature

Nowadays, medicinal herbs and their phytochemicals have emerged as a great therapeutic option for many disorders. However, poor bioavailability and selectivity might limit their clinical application. Therefore, bioavailability is considered a notable challenge to improve bio-efficacy in transporting dietary phytochemicals. Different methods have been proposed for generating effective carrier systems to enhance the bioavailability of phytochemicals. Among them, nano-vesicles have been introduced as promising candidates for the delivery of insoluble phytochemicals. Due to the easy preparation of the bilayer vesicles and their adaptability, they have been widely used and approved by the scientific literature. The first part of the review is focused on introducing phytosome technology as well as its applications, with emphasis on principles of formulations and characterization. The second part provides a wide overview of biological activities of commercial and non-commercial phytosomes, divided by systems and related pathologies. These results confirm the greater effectiveness of phytosomes, both in terms of biological activity or reduced dosage, highlighting curcumin and silymarin as the most formulated compounds. Finally, we describe the promising clinical and experimental findings regarding the applications of phytosomes. The conclusion of this study encourages the researchers to transfer their knowledge from laboratories to market, for a further development of these products.

Analytical tools and evaluation strategies for nanostructured lipid carrier-based topical delivery systems

INTRODUCTION

The inception of nanostructured lipid carriers (NLCs) proved to be a revolutionary step toward the treatment of dermatological disorders. To uncover its true potential, it is imperative that the system be characterized and evaluated comprehensively.

AREAS COVERED

The present review has been written to furnish an in-depth account of analytical tools and evaluation procedures under one roof. Besides discussing the challenges of topical delivery and benefits of NLCs, the paper elaborates on their physicochemical characterization. Further, in vitro evaluation of NLCs for dermatological benefits, followed by their evaluation in a hydrogel/cream base is covered. Lastly, disease-specific evaluation of NLC-based formulations is presented.

EXPERT OPINION

The research endeavors for NLCs have largely focused on the fabrication of NLCs for different bioactives. However, scientific efforts should be aimed toward the lesser explored realm of NLCs, i.e. exploitation of analytical techniques, such as Parelectric spectroscopy, Electron Spin Resonance, and Nuclear Magnetic Resonance spectroscopy. NLCs have been proven for their potential to foster the therapeutic modalities applicable to cutaneous disorders. More attention needs to be devoted to their evaluation for disease-specific parameters. The futuristic steps must involve clinical studies, to lay the path for their commercialization.

Biotin anchored nanostructured lipid carriers for targeted delivery of doxorubicin in management of mammary gland carcinoma through regulation of apoptotic modulator

Mammary gland tumour has the highest incidence rate and mortality in women, worldwide. The present study envisaged a molecularly targeted nanostructured lipid carrier (NLCs) for doxorubicin (Dox) delivery capable of inducing cellular apoptosis in mammary gland tumour. NLCs were prepared utilizing Perilla frutescens oil (54-69% ω3-fatty acid) as liquid lipid to enhance entrapment of Dox through molecular ion pairing. Biotin decorated NLCs (b-Dox-NLCs) were evaluated in vitro and in vivo. The b-Dox-NLCs showed particle size of 105.2 ± 3.5 nm, zeta potential -35 ± 2 mV, entrapment 99.15 ± 1.71%, drug content 19.67 ± 2.6 mg.g-1, biotin content 5.85 ± 0.64 µg.g-1 and drug release 98.67 ± 2.43% (facilitated by acidic microenvironment) respectively. MTT assay and Flow cytometric analysis revealed higher anti-proliferative capability of b-Dox-NLCs to force apoptosis in MCF-7 cell line vis-à-vis marketed Dox, evidenced by reactive oxygen species level and mitochondrial membrane potential mediated apoptosis. Enhanced antitumor targeting, therapeutic safety and efficacy was exhibited by b-Dox-NLCs, as investigated through tumour volume, animal survival, weight variation, cardiotoxicity and biodistribution studies in 7,12-Dimethylbenz[a]anthracene induced mammary gland tumour. Immunoblotting assay demonstrated b-Dox-NLCs downregulated anti-apoptotic proteins, i.e. bcl-2, MMP-9 while upregulated pro-apoptotic proteins, i.e. caspase-9, p16 and BAX. The experimental results suggest that biotinylated ω3-fatty acid augmented NLCs loaded with Dox are capable of inducing programmed cell death in mammary tumour and can be utilized as safe and effective delivery system with enhanced potential for mammary gland carcinoma therapy.

Flavonolignans: One Step Further in the Broad-Spectrum Approach of Cancer

BACKGROUND

The small chemical class of flavonolignans encompasses unique hybrid molecules with versatile biological activities. Their anticancer effects have received considerable attention, and a large body of supporting evidence has accumulated. Moreover, their ability to interact with proteins involved in drug resistance, and to enhance the effects of conventional chemotherapeutics in decreasing cell viability make them influential partners in addressing cancer.

OBJECTIVE

The review provides an outline of the various ways in which flavonolignans advance the combat against cancer. While the main focus falls on flavonolignans from milk thistle, attention is drawn to the yet, underexplored potential of less known flavonolignan subgroups derived from isoflavonoids and aurones.

METHODS

Proceeding from the presentation of natural flavonolignan subtypes and their occurrence, the present work reviews these compounds with regard to their molecular targets in cancer, anti-angiogenetic effects, synergistic efficacy in conjunction with anticancer agents, reversal of drug resistance, and importance in overcoming the side effects of anticancer therapy. Recent advances in the endeavor to improve flavonolignan bioavailability in cancer are also presented.

CONCLUSIONS

Significant progress has been achieved in detailing the molecular mechanisms of silybin and its congeners in experimental models of cancer. The availability of novel formulations with improved bioavailability, and data from phase I clinical trials in cancer patients provide an encouraging basis for more extensive trials aimed at evaluating the benefits of Silybum flavonolignans in cancer management. On the other hand, further research on the antitumor efficacy of iso-flavonolignans and other subtypes of flavonolignans should be pursued.

Development of Topical Nanocarriers for Skin Cancer Treatment Using Quality by Design Approach

BACKGROUND

One of the most compelling medical challenges of this century is the treatment of cancer and among them, skin cancer is the most common type. Thus, current treatments need to be renewed continuously to handle this challenge.

OBJECTIVE

This review presents considerations which can be employed during the development of nanosized formulations dedicated to the topical treatment of skin cancer. We aimed to collect and organize literature data on the treatment options for skin cancer in order to determine the required quality attributes of an effective dermal anticancer formulation.

METHOD

With the consideration of the Quality by Design (QbD) approach related to the development of new pharmaceutical formulations, a cost-saving process ensuring a high-quality product taking into account patient expectations, industrial and regulatory aspects can be achieved. Furthermore, this concept is highly recommended by regulatory agencies.

RESULTS

Our work discusses the current therapies, active agents, drug carrier systems, and evaluation methods in connection with the treatment of skin cancer and outlines Critical Quality Attributes which need to be considered during the development of a nanosized dermal anticancer formulation.

CONCLUSION

The first part of this review summarizes the most important topical treatment therapies for skin cancer and highlights the future therapeutic perspectives, focusing on the benefits of nanotechnology and dermal administration. The second part outlines the critical points of nanosized dermal anticancer formulation development in the view of QbD approach. Our research emphasizes the application of QbD method for a rationalized and more effective anticancer formulation development process.

Silymarin-loaded nanostructured lipid carrier gel for the treatment of skin cancer

Aim: The present study was aimed at determining the antiproliferative, antioxidant, anti-inflammatory and antitumor activity of developed silymarin-nanostructured lipid carrier (NLC) gel. Materials & methods: B16 melanoma cell line and albino mice were used as ex vivo and in vivo models, respectively, to evaluate the aforementioned pharmacological activities. Results: The volume of large tumors significantly (p < 0.05) reduced from 5.02 to 3.05 mm3, levels of IL-1α and TNF-α were significantly (p < 0.001) lower and levels of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) significantly (p < 0.0001) increased in the group treated with silymarin-NLC gel. Furthermore, in skin treated with placebo and conventional gels, a basosquamous carcinoma and squamous cell carcinoma were noticed, respectively. Conclusion: Silymarin-NLC gel presented better treatment outcomes compared with silymarin-conventional gel.

Hyaluronic Acid Decorated Naringenin Nanoparticles: Appraisal of Chemopreventive and Curative Potential for Lung Cancer

Lung carcinoma is the most common cancer in men and second in women (preceded by breast cancer) worldwide. Around 1 in 10 of all cancers diagnosed in men, lung cancer contributed to a total fraction of 20% cancer deaths. Naringenin (NAR) is well known for its chemopreventive properties since ancient times but lacks an appropriate delivery carrier. The objective of present study was to expand the functionality of naringenin loaded poly caprolactone (PCL) nanoparticles in terms of release, chemoprevention and therapeutics. Polymeric nanoparticles such as PCL lack target specificity; hence, surface modification was attempted using layer by layer technique (LBL) to achieve improved and desired delivery as well as target specificity. The designing of Hyaluronic acid (HA) decorated PCL nanoparticles were prepared by utilizing self-assembling LBL technique, where a polycationic layer of a polymer was used as a linker for modification between two polyanionic layers. Additionally, an attempt has been made to strengthen the therapeutic efficacy of PCL nanocarriers by active targeting and overcoming the extracellular matrix associated barriers of tumors using HA targeting cluster determinant 44 receptor (CD44). Cell cytotoxicity study on A549 cells and J774 macrophage cells depicted enhanced anticancer effect of NAR-HA@CH-PCL-NP with safe profile on macrophages. Uptake study on A549 cells advocated enhanced drug uptake by cancer cells. Cell cycle arrest analysis (A549 cell lines) demonstrated the superior cytotoxic effect and active targeting of NAR-HA@CH-PCL-NP. Further chemopreventive treatment with NAR-HA@CH-PCL-NP was found effective in tumor growth inhibitory effect against urethane-induced lung cancer in rat. In conclusion, developed formulation possesses a promising potential as a therapeutic and chemopreventive agent against urethane-induced lung carcinoma in albino wistar rats.

Design of topical nanostructured lipid carrier of silymarin and its effect on 7,12-dimethylbenz[a]anthracene (DMBA) induced cellular differentiation in mouse skin

Effect of silymarin NLC on DMBA induced cell changes in mouse skin.