Recent Advances on Natural and Non-Natural Xanthones as Potential Anticancer Agents: A Review.

BACKGROUND: Xanthones, natural or synthetic, due to their wide range of biological activities, have become an interesting subject of investigation for many researchers. Xanthonic scaffold has proven to have a vital role in anticancer drug development since many of its derivatives have shown anticancer activities on various cell lines. In addition, targeting epigenetic markers in cancer has yielded promising results. There have also been reports on the impact of xanthone and related polyphenolic compounds on epigenetics markers in cancer prevention and therapy. OBJECTIVE: The objective of this review is to comprehensively highlight the main natural and nonnatural sources of xanthones having potential anti-cancer effects along with their key structural elements, structure-activity relationships (SARs), mechanisms of action, and epigenetic profile of xanthone- based anti-cancer compounds. The challenges and future directions of xanthone-based therapies are also discussed briefly. METHOD: The methods involved in the preparation of the present review included the collection of all recent information up to November 2021 from various scientific databases, indexed periodicals, and search engines such as Medline Scopus, Google Scholar, PubMed, PubMed Central, Web of Science, and Science Direct. RESULTS: Exploration of the diversity of the xanthone scaffold led to the identification of several derivatives having prominent anti-cancer activity. Their unique structural diversity and synthetic modifications showed the ongoing endeavour of enriching the chemical diversity of the xanthone molecular framework to discover pharmacologically interesting compounds. However, studies regarding their modes of action, pharmacokinetic properties, clinical data, epigenetics, and safety are limited. CONCLUSION: Elucidation of the exact biological mechanisms and the associated targets of xanthones will yield better opportunities for these compounds to be developed as potential anticancer drugs. Further clinical studies with conclusive results are required to implement xanthones as treatment modalities in cancer.

Nanotechnology Integration for SARS-CoV-2 Diagnosis and Treatment: An Approach to Preventing Pandemic.

The SARS-CoV-2 outbreak is the COVID-19 disease, which has caused massive health devastation, prompting the World Health Organization to declare a worldwide health emergency. The corona virus infected millions of people worldwide, and many died as a result of a lack of particular medications. The current emergency necessitates extensive therapy in order to stop the spread of the coronavirus. There are various vaccinations available, but no validated COVID-19 treatments. Since its outbreak, many therapeutics have been tested, including the use of repurposed medications, nucleoside inhibitors, protease inhibitors, broad spectrum antivirals, convalescence plasma therapies, immune-modulators, and monoclonal antibodies. However, these approaches have not yielded any outcomes and are mostly used to alleviate symptoms associated with potentially fatal adverse drug reactions. Nanoparticles, on the other hand, may prove to be an effective treatment for COVID-19. They can be designed to boost the efficacy of currently available antiviral medications or to trigger a rapid immune response against COVID-19. In the last decade, there has been significant progress in nanotechnology. This review focuses on the virus's basic structure, pathogenesis, and current treatment options for COVID-19. This study addresses nanotechnology and its applications in diagnosis, prevention, treatment, and targeted vaccine delivery, laying the groundwork for a successful pandemic fight.