Current Topics in Medicinal Chemistry - Volume 23, Issue 10, 2023

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, 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, triazole 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.

As a circadian rhythm hormone, melatonin is widely present in the body and has rich physiological functions. Compared to its prominent circadian role, melatonin has been extensively studied in many fields as an ancient antioxidant. In addition to being considered a potent antioxidant, melatonin has also been found to play an important role in mitochondrial homeostasis. Mitochondrial oxidative stress plays a crucial role in the occurrence and development of atherosclerosis. Therefore, the possible therapeutic value of melatonin as an antioxidant targeting mitochondria in atherosclerosis is worth exploring. The most widespread clinical applications of melatonin are in circadian rhythms and sleep, but the cardiovascular system may be the most promising area.

The adverse toxicities and stemness are two major factors that constrained the usage of therapeutic strategies to target several cancer types. Previous studies explored the efficacy of PI3K/mTOR inhibitors, pan-PI3K inhibitors, and isoform-specific inhibitors against several cancer types, and many of them are currently in clinical trials. The current review described the efficacy of alkaloids derived from dietary plant sources in developing a new anti-cancer to reduce the prevalence of cancer through the modulation of apoptosis, autophagy, and ferroptosis. We have substantially collected the information pertinent to several intracellular pathways, including PI3K signaling, apoptosis, ferroptosis, and autophagy in modulating cancer progression mediated by the plantderived alkaloids such as daurisoline, dauricine, vasicine, vasicinone, 2-Acetyl-benzylamine, nuciferine, liensinine, gramine, and berbamine. These alkaloids exhibit significant anti-cancer potential to inhibit cancer cells by enhancing the intracellular ROS level and modulation of several signaling pathways, mainly through the PI3K/AKT pathway. These alkaloids can modulate chemotherapeutic agents' efficacy in various cancer cells, both in vitro and in vivo models. Overall the futures for the continued use of alkaloids from natural sources against cancer have to be extended, with the implementation of significant enhancements in the chemistry of these alkaloids for targeted delivery. In this review, we have selected major bioactive alkaloids of dietary and medicinal plants origin and discussed the anti-cancer and combinatorial therapeutic implications of these compounds with several FDA-approved drugs against various cancer cells.

The Wnt/β-catenin signaling pathway plays a crucial role in the development, tissue homeostasis, angiogenesis, and carcinogenesis of cancer. Mutations and excessive activation of the Wnt/β-catenin signaling pathway in cancer cells and cancer stem cells lead to drug resistance and recurrence of cancer in patients treated with conventional chemotherapy and radiotherapy. Upregulation of proangiogenic factors is persistently induced by hyperactivated Wnt/β-catenin signaling during tumor angiogenesis. Furthermore, mutations and hyperactivated Wnt/β-catenin signaling are associated with worse outcomes in several human cancers, including breast cancer, cervical cancer, and glioma. Therefore, mutations and hyperactivation of Wnt/β-catenin signaling create challenges and limitations in cancer treatment. Recently, in silico drug design as well as high-throughput assays and experiments have demonstrated the promising anticancer efficacy of chemotherapeutics, such as blocking the cancer cell cycle, inhibiting cancer cell proliferation and endothelial cell angiogenesis, inducing cancer cell apoptosis, removing cancer stem cells, and enhancing immune responses. Compared to conventional chemotherapy and radiotherapy, small-molecule inhibitors are considered the most promising therapeutic strategy for targeting the Wnt/β-catenin signaling pathway. Herein, we review the current small-molecule inhibitors of the Wnt/β-catenin signaling pathway, focusing on Wnt ligands, Wnt receptors, the β-catenin destruction complex, ubiquitin ligases and proteasomal destruction complex, β-catenin, β-catenin-associated transcriptional factors and coactivators, and proangiogenic factors. We describe the structure, mechanisms, and functions of these small molecules during cancer treatment in preclinical and clinical trials. We also review several Wnt/β-catenin inhibitors reported to exhibit anti-angiogenic effects. Finally, we explain various challenges in the targeting of the Wnt/β-catenin signaling pathway in human cancer treatment and suggest potential therapeutic approaches to human cancer.

Tumors of the urinary system include those in the urinary and reproductive systems, of which tumors of the prostate, bladder, and kidney have the highest incidence. In recent years, due to changes in dietary structure, prostate cancer has become the most common type of male genitourinary system cancer. Furthermore, due to tobacco consumption, increases in industrialization, and the age of the population, the incidence of bladder cancer in both males and females in both urban and rural areas, has shown an increasing trend. The incidence and mortality of kidney cancer have also increased and negatively affected the lives and health of all residents. While surgery, radiotherapy, and chemotherapy have greatly improved the cure and survival rates of patients with urinary tumors, we lack methods for early detection and effective long-term treatment. New tools and methods for diagnosis and treatment are thus urgently needed. Recently, CRISPR/Cas9 has become an efficient method to alter the genome in many organisms. It can be used to activate or inhibit gene expression, which greatly facilitates the editing of targeted genes, both in vivo and in vitro. It provides a powerful scientific research tool to analyze the mechanisms of disease occurrence and development and to develop advanced targeted drug delivery. The diagnosis and treatment of human tumors will consequently be improved as this technology will surely accelerate cancer research. In this article, we discuss how CRISPR/Cas9 technology can be used to research and treat genitourinary system tumors will consequently be improved as this technology will surely accelerate cancer research. Here, we review the current applications of CRISPR/Cas9 technology for genitourinary system tumor research and therapy.

Due to their unique biological functionality, nanocarriers can be designed to deliver various anti-tumor drugs in vivo, which has a wide and important application prospect in the field of tumor therapy. However, poor biosafety, short blood circulation time, and weak targeting ability still limit the application of nanoparticles in tumor therapy. In recent years, with the development of biomedicine, the biomimetic technology-based biomembrane-mediated drug delivery system is expected to achieve a breakthrough in tumor-targeted therapy due to low immunogenicity, tumor targeting, the adjustability and versatility of intelligent nanocarrier design. This paper mainly reviews the research process of different types of the cell membrane (erythrocyte membrane, cancer cell membrane, bacterial membrane, stem cell membrane, and hybrid membrane)-camouflaged nanoparticles in tumor therapy, as well as the challenges and development prospects in clinical application.

Lung cancer is one of the most common malignant tumors, and its death rate is much higher than that of colon, kidney, breast, and prostate cancers, and its 5-year survival rate is only 18%. Lung cancer has no specific clinical symptoms in its early stages and lacks effective detection, making early detection difficult. The survival rate for advanced lung cancer is meager, with a median survival of only 12 months for stage IIIB/IV non-small cell lung cancer treated with platinumbased chemotherapy. Exosomes could provide vital information for the early diagnosis of lung cancer and have the potential to become a tumor marker for lung cancer. In addition, scientists have proposed encouraging ways to treat lung cancer by loading drugs, proteins, microRNAs, and siRNAs into exosomes. Therefore, studying lung cancer exosomes and exosomal nano drugs will provide new ideas and approaches for the diagnosis and treatment of lung cancer. This paper reviews the progress of research on the biological functions of exosomes and exosomal nanomedicines and their applications in clinical practice.