BACKGROUND: Effective cancer treatment still challenges medicine since the strategies employed so far are not sufficiently safe and capable of specifically eliminating tumor cells. Prostate cancer (PCa) is a highly incident malignant neoplasm, and the outcome of patients, especially those with advanced castration-resistant PCa (CRPC), depends directly on the efficacy of the therapeutic agents, such as docetaxel (DOC). OBJECTIVE: This study investigated the synergistic potentiation of 4-nerolidylcatechol (4-NC) with DOC in inhibiting androgen-independent PCa cells. METHODS: The cytotoxic effect of 4-NC was evaluated against non-tumorigenic (RWPE-01) and PCa cell lines (LNCaP and PC-3), and the antiproliferative potential of 4-NC was assessed by flow cytometry and colony formation. The Chou-Talalay method was applied to detect the synergistic effect of 4-NC and DOC, and the mechanism of anticancer activities of this combination was investigated by analyzing players in epithelial-mesenchymal transition (EMT). RESULTS: 4-NC significantly reduced the viability of PC-3 cells in a dose-dependent manner, decreasing colony formation and proliferation. The combination of 4-NC and DOC was synergistic in the androgen-independent cells and allowed the reduction of DOC concentration, with increased cytotoxicity and induction of apoptosis when compared to compounds alone. Furthermore, when 4-NC was co-administered with DOC, higher expression levels of proteins associated with the epithelial phenotype were observed, controlling EMT in PC-3 cells. CONCLUSION: Collectively, these data demonstrated, for the first time, that the combination of 4-NC with reduced doses of DOC could be especially valuable in the suppression of oncogenic mechanisms of androgen-independent PCa cells.

BACKGROUND: Arylindole derivatives are promising scaffolds in the design of new drugs. These scaffolds exhibit a wide biological activity, including inhibition of COX-2, antitumor activity, receptor GABA agonism, and estrogen receptor modulation. OBJECTIVE: Taking this into account, this paper presents a study to understand the inhibitory action of certain 2-arylindole derivatives, specifically a series of 2,3-diarylindoles with IC50 values from 0.006 nM to 100 nM, on the COX-2 enzyme and supports its structural-activity relationship (SAR) through molecular docking simulations. METHODS: Applying molecular modelling, especially molecular docking, we assessed the SAR of a series of 2,3-arylindoles derivatives in the COX-2 enzyme. RESULTS: The results indicated that Gly 526 and Phe 381 residues are relevant for improving inhibitory activity on para-substituted 3-phenyl- compounds. Arg 120 was also demonstrated to be an important residue for COX-2 inhibition since it enables a π-cation interaction with the best compound in series A5 (experimental IC50 = 0.006 nM determined in advance). Furthermore, COX-2 presents flexibility in some regions of the active site to adequately accommodate 5-substituted compounds containing an indole ring. CONCLUSION: Therefore, such structural features can be used as support for further Structural-Based Drug Design (SBDD) and/or Ligand-Based Drug Design (LBDD) studies on new selective COX-2 inhibitors.

Alzheimer's disease (AD) is drawing scientists' consideration, being one of the gravest diseases mankind will have to battle against in the near future. The number of people with AD is expected to triple in the next 40 years. It is a most common age-related multifactorial neurodegenerative disease and characterized by two histopathological hallmarks; the formation of senile plaques composed of the amyloid-β (Aβ) peptide and neurofibrillary tangles composed of hyperphosphorylated tau protein. Discovery and development of rationally designed multi-targeted ligands for the management of AD could be more beneficial than classical single targeted molecules. Acridine, a heterocyclic nucleus is a sole moiety in various existing drug molecules such as quinacrine (antimalarial), acriflavine and proflavine (antiseptics), ethacridine (abortifacient), amsacrine and nitracine (anticancer) and tacrine (anti-Alzheimer). It is proposed that acridine may combat the AD by acting on several targets like acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), dual specificity tyrosine kinase 1A (Dyrk 1A), amyloid and prion protein (PrPC) etc. involved in its pathogenesis. The main aim of this compilation is to review the most promising therapeutic developments within the vast research area dealing with acridine derivatives. Further research is required to evaluate the effectiveness of the acridine derivatives with various substitutions in the treatment of AD. In conclusion, our review will suggest the potentiality of the versatile acridine framework for drug designing and developing novel multi-target inhibitors for the Alzheimer's disease.

Metal-organic frameworks (MOFs) are porous, crystalline materials made up of organic ligands and metal ions/metal clusters linked by coordinative bonds. This large family is becoming increasingly popular for drug delivery due to their tuneable porosity, chemical composition, size and shape, and ease of surface functionalization. There has been a growing interest over the last decades in the design of engineered MOFs with controlled sizes for a variety of biomedical applications. Starting with the MOFs classification adapted for drug delivery systems (DDSs) based on the types of constituting metals and ligands. MOFs are appealing drug delivery vehicles because of their substantial drug absorption capacity and slow-release processes, which protect and convey sensitive drug molecules to target areas. Other guest materials have been incorporated into MOFs to create MOF-composite materials, which have added additional functionalities such as externally triggered drug release, improved pharmacokinetics, and diagnostic aids. Magnetic nanoparticles in MOFs for MRI image contrast and polymer coatings that increase blood circulation time are examples of synthetically adaptable MOF-composites. By including photosensitizers, which exert lethal effects on cancer cells by converting tumour oxygen into reactive singlet oxygen (1O2), metal-organic frameworks have been employed for photodynamic treatment (PDT) of malignancies among a multitude of nanosized therapies. Importantly, a variety of representative MOF applications are described from the perspectives of pharmaceutics, disease therapy, and advanced drug delivery systems. However, because of their weak conductivity, selectivity, and lack of modification sites, MOF materials' uses in electrochemical biosensing are restricted. MOF-based composites provide excellent electrical conductivity and robust catalytic activity by adding functionalized nanoparticles into MOF structures, which process benefits over single component MOFs.

Molecular hybridization is one of the recent stratagems in medicinal chemistry to synthesize a novel hybrid molecule having better affinity and efficacy by combining two or more pharmacophoric moieties. Molecular hybridization, i.e., a linker or framework integration technique, can be used to connect the two pharmacophoric components. It has often been found that hybrid compounds perform more effectively and possess lower toxicity than their parent molecules. In order to create a new generation of effective and safe therapeutic candidates, such as anti-cancer, anti-viral, anti-HIV, antioxidant, and antibacterial, for a variety of frontline diseases, several articles have been published that discuss the molecular hybridization of preclinically or clinically proven compounds. Isatin and its derivatives have been studied extensively due to diversified biological activities, including antitumor, antimicrobial, anti-inflammatory, analgesic, antiviral, antioxidant, anticonvulsant activity, etc. Similarly, 1,2,3-triazoles have received significant interest as a bio-isostere in medicinal chemistry for generating a large number of pharmaceutically significant molecules. As it possesses diversified physiochemical properties, such as hydrogen bond formation capacity, ease of synthesis, moderate dipole moment, stability towards acidic/basic hydrolysis, inertness towards oxidizing/reducing agents, and good binding potential with several biological targets, isatin is an important choice of the medicinal chemists for the novel medication development. The aim of the current review is to summarize the research articles showing the pharmacological significance of hybrid molecules containing isatin and 1,2,3-triazole moieties. The present review may assist chemists in designing and synthesizing isatin-1,2,3-triazole hybrids with better efficacy and low cytotoxicity.

Tropical, vector-borne, and neglected diseases with a limited number of medication therapies include Leishmaniasis, Malaria, Chagas and Human African Trypanosomiasis (HAT). Chromones are a large class of heterocyclic compounds with significant applications. This heterocycle has long aroused the interest of scientists and the general public from biosynthetic and synthetic points of view owing to its interesting pharmacological activities. Chromones and their hybrids and isomeric forms proved to be an exciting scaffold to investigate these diseases. The in vitro activities of Chromone, Chromane, and a panel of other related benzopyran class compounds against Trypanosoma brucei rhodesiense, Trypanosoma brucei gambiense, Trypanosoma cruzi, and numerous Leishmanial and Malarial species were investigated in our previous studies. The current article briefly describes the neglected diseases and the current treatment. This review aims to attempt to find better alternatives by scrutinizing natural and synthetic derivatives for which chromones and their analogues were discovered to be a new and highly effective scaffold for the treatment of neglected diseases, including compounds with dual activity or activity against multiple parasites. Additionally, the efficacy of other new scaffolds was also thoroughly examined. This article also discusses prospects for identifying more unique targets for the disease, focusing on flavonoids as drug molecules that are less cytotoxic and high antiprotozoal potential. It also emphasizes the changes that can be made while searching for potential therapies-comparing existing treatments against protozoal diseases and the advantages of the newer chromone analogues over them. Finally, the structure-activity relationship at each atom of the chromone has also been highlighted.

Tumor-associated macrophages (TAMs) play a pivotal role in the progression and resistance of tumors to different anticancer drugs. TAMs can modulate the tumor microenvironment (TME) in favor of immune system exhaustion. The interactions of TAMs with TME can affect the function of cytotoxic CD8+ T lymphocytes (CTLs) and natural killer (NK) cells. Furthermore, TAMs can induce cancer cell proliferation by releasing some growth factors, such as transforming growth factor (TGF)-β. TAMs have several positive cross-talks with other immune suppressive cells such as regulatory T cells (Tregs), myeloid-derived suppressor cells (MDSCs), cancer-associated fibroblasts (CAFs), and cancer cells, leading to the release of growth factors, the proliferation of cancer cells and tumor growth. These interactions also can induce invasion and migration of cancer cells, angiogenesis, and metastasis. The inhibition of TAMs is an intriguing strategy for overcoming tumor resistance and suppression of cancer cells. Some natural-derived agents such as melatonin, curcumin, resveratrol, apigenin, and other flavonoids have shown the ability to modulate TME, including TAMs. These adjuvants may be able to boost antitumor immunity through the modulation of TAMs. This review explains the modulatory effects of some well-known naturally derived agents on the activity of TAMs. The modulation of TAMs by these agents may be useful in suppressing tumor growth and invasion.

Trypanosomiasis is caused by parasitic protozoan trypanosomes in vertebrates. T. cruzi and T. brucei are causative agents of Chagas disease (CD) and Human African Trypanosomiasis (HAT), respectively. These life-threatening diseases are a serious threat to public health, with considerable incidence in sub-Saharan African and continental Latin America countries. Although WHO validated mitigated number of HAT cases in Togo (June 2020) and Cote d'Ivoire (December 2020), serious efforts need to be performed for the elimination of the disease. Antigenic variation of trypanosomal parasites provides a major bottleneck for developing effective vaccines. In the absence of human vaccines or chemoprophylaxis, the control of trypanosomatid infections may be envisaged through the eradication of vectors, management of animal reservoirs, and chemotherapy. A small number of chemical agents are currently available for antitrypanosomal treatments, and most of them are associated with toxicity, lack of efficacy, and non-oral route of administration. Given the restricted applicability of current medications, numerous efforts have been made for the synthesis and biological evaluation of heterocyclic scaffolds as antitrypanosomal candidates. In light of the above considerations, we were prompted to describe chemical diversity within privileged 5-membered heterocycles (imidazoles, thiazoles, triazoles and tetrazoles) as antitrypanosomal agents. The main purpose of the study was to throw light on the structure-activity relationship (SAR) of the relevant structures. To capture the recent structural diversity within reported cases, small molecules that belonged to the recent 7-year period (2015-2021) have been discussed. The available medications have also been briefly reviewed.

BACKGROUND: Microbial diseases, specifically originating from viruses are the major cause of human mortality all over the world. The current COVID-19 pandemic is a case in point, where the dynamics of the viral-human interactions are still not completely understood, making its treatment a case of trial and error. Scientists are struggling to devise a strategy to contain the pandemic for over a year and this brings to light the lack of understanding of how the virus grows and multiplies in the human body. METHODS: This paper presents the perspective of the authors on the applicability of computational tools for deep learning and understanding of host-microbe interaction, disease progression and management, drug resistance and immune modulation through in-silico methodologies which can aid in effective and selective drug development. The paper has summarized advances in the last five years. The studies published and indexed in leading databases were included in the review. RESULTS: Computational systems biology works on an interface of biology and mathematics and intends to unravel the complex mechanisms plying between the biological systems and the inter and intra species dynamics using computational tools, and high-throughput technologies developed on algorithms, networks and complex connections to simulate cellular biological processes. CONCLUSION: Computational strategies and modelling integrate and prioritize microbial-host interactions and may predict the conditions in which the fine-tuning attenuates. These microbial-host interactions and working mechanisms are important from the aspect of effective drug designing and fine-tuning the therapeutic interventions.