Non-small-cell lung cancer (NSCLC), which accounts for approximately eighty-five percent of lung cancer diagnoses worldwide, is a malignancy with high incidence and mortality rates. Among the various antitumor compounds, organic selenium-containing compounds have emerged as a promising class of therapeutic agents for cancer treatment. In the present study, SLL-1A-16, a new organoselenium small molecule, was discovered to exhibit antiproliferative activity against NSCLC both in vitro and in vivo. Treatment with SLL-1A-16 significantly inhibited NSCLC cell proliferation and induced apoptosis and autophagy. Mechanistically, SLL-1A-16 inhibited cell proliferation through G1-S phase arrest by reducing cyclin D1 and CDK4 expression. Additionally, SLL-1A-16 significantly induced apoptosis by upregulating cleaved caspase 3 and Bax expression, while downregulating Bcl-2 levels. Our study also demonstrated that SLL-1A-16 induced autophagy in NSCLC cells by inhibiting the Akt/mTOR pathway. Overall, our findings suggest that SLL-1A-16 could induce cell cycle arrest, apoptosis and autophagy in NSCLC cells by inhibiting the Akt/mTOR signaling pathways, providing a theoretical basis for the potential clinical application of SLL-1A-16 as a chemotherapeutic agent in NSCLC treatment.
Cancer patients undergoing chemotherapy are highly susceptible to infections owing to their compromised immune system, which also promotes cancer progression through inflammation. Thus, this study aimed to develop novel chemotherapeutic agents with both anticancer and antimicrobial properties. A series of diarylurea derivatives based on pyridazinone scaffolds were designed, synthesized, and characterized as surrogates for sorafenib. The synthesized compounds were tested for their antimicrobial activity and screened against 60 cancer cell lines at the National Cancer Institute (NCI). Compound 10h exhibited potent antibacterial activity against Staphylococcus aureus (MIC = 16 μg mL-1), whereas compound 8g showed significant antifungal activity against Candida albicans (MIC = 16 μg mL-1). Additionally, ten compounds were further evaluated for VEGFR-2 inhibition, with compound 17a showing the best inhibitory activity. Compounds 8f, 10l, and 17a demonstrated significant anticancer activity against melanoma, NSCLC, prostate cancer, and colon cancer, with growth inhibition percentages (GI%) ranging from 62.21% to 100.14%. Compounds 10l and 17a were selected for five-dose screening, displaying GI50 values of 1.66-100 μM. Compound 10l induced G0-G1 phase cell cycle arrest in the A549/ATCC cell line, increasing the cell population from 85.41% to 90.86%. Gene expression analysis showed that compound 10l upregulated pro-apoptotic genes p53 and Bax and downregulated the anti-apoptotic gene Bcl-2. Molecular docking studies provided insights into the binding modes of the compounds to the VEGFR-2 enzyme. In conclusion, the pyridazinone-based diarylurea derivatives developed in this study show promise as dual-function antimicrobial and anticancer agents, warranting further investigation.
The cell entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is mediated by the interaction between the receptor-binding domain of its spike (S) protein and human angiotensin-converting enzyme 2 (ACE2). Quercetin, a flavonoid found abundantly in plants, shows potential as a SARS-CoV-2 S:ACE2 inhibitor but is known to have low bioavailability. Modification of quercetin by capping its hydroxyl moieties could enhance the metabolic stability, solubility, and bioavailability, and reduce toxicity. In this study, sixteen (16) O-modified quercetin derivatives were synthesized by incorporating alkyl and acyl moieties of varying lengths, sizes, and polarities to the hydroxyl groups. The SARS-CoV-2 S:ACE2 inhibitory activity and toxicity of the synthesized derivatives were assessed in vitro, and their physicochemical properties, pharmacokinetics, and drug-likeness were predicted and evaluated using the SwissADME web tool. Results showed that functionalization of the hydroxyl moieties of quercetin generally resulted in more potent inhibitors (>50% inhibition). Five (5) derivatives displayed a dose-dependent inhibition against the SARS-CoV-2 S:ACE2 interaction with promising IC50 values (i.e., 2e (IC50 = 7.52 μM), 3a (IC50 = 5.00 μM), 3b (IC50 = 25.70 μM), 3c (IC50 = 2.22 μM), and 4b (IC50 = 3.28 μM)). Moreover, these compounds exhibited low hepato-, nephro-, and cardiotoxicity, and their SwissADME profiles indicated favorable physicochemical, pharmacokinetic, and drug-like properties, suggesting their potential as promising lead SARS-CoV-2 S:ACE2 inhibitors.
TNBC has been recognized as the most highly aggressive breast cancer without chemotherapeutic drugs. A collection of oridonin hybrids consisting of conventional antitumor pharmacophores including nitrogen mustards and adamantane-1-carboxylic acid were synthesized by deletion or blockade of multiple hydroxyl groups and structural rearrangement. Compound 11a showed the most promising anti-TNBC activity with nearly 15-fold more potent antiproliferative effects than oridonin against MDA-MB-231 and HCC1806. Moreover, 11a significantly inhibited HCC1806, MDA-MB-231 and MDA-MB-468 cell proliferation by arresting cells at the G2/M phase in a dose-dependent manner. Furthermore, 11a could trigger dose-dependently early and late apoptosis in those indicated cell lines. More importantly, 11a could significantly increase p21, γH2AX and cleaved PARP accumulation in a dose-dependent manner. Furthermore, compound 11a exhibited better stability than oridonin in a plasma assay. Taken together, all results demonstrated that 11a may warrant further investigation as a promising anticancer drug candidate for the treatment of TNBC.
Accumulating evidence suggests that the root of drug chemoresistance in ovarian cancer is tightly associated with subpopulations of cancer stem cells (CSCs), whose activation is largely associated with signal transducer and activator of transcription 3 (STAT3) signaling. Recently, celastrol has shown a significant anti-cancer effect on ovarian cancer, but its clinical translation is very challenging due to its oral bioavailability and high organ toxicity. In this study, a celastrol derivative (Cel-N) was synthesized to augment the overall efficacy, and its underlying mechanisms were also explored. Different ovarian cancer cells, SKOV3 and A2780, were used to evaluate and compare the anticancer effects. Cel-N displayed potent activities against all the tested ovarian cancer cells, with the lowest IC50 value of 0.14-0.25 μM. Further studies showed that Cel-N effectively suppressed the colony formation and sphere formation ability, decreased the percentage of CD44+CD24- and ALDH+ cells, and induced ROS production. Furthermore, western blot analysis indicated that Cel-N significantly inhibited both Tyr705 and Ser727 phosphorylation and reduced the protein expression of STAT3. In addition, Cel-N could dramatically induce apoptosis and cell cycle arrest, and inhibit migration and invasion. Importantly, Cel-N showed a potent antitumor efficacy with no or limited systemic toxicity in mice xenograft models. The anticancer effect of Cel-N is stronger than celastrol. Cel-N attenuates cancer cell stemness, inhibits the STAT3 pathway, and exerts anti-ovarian cancer effects in cell and mouse models. Our data support that Cel-N is a potent drug candidate for ovarian cancer.
Molecular glues and bifunctional small molecules, such as targeted protein degraders, induce protein proximity to mediate gain-of-function pharmacology. Emerging technologies that synthetically manipulate protein surfaces to create neoproteins, and the development of covalent chemical probes for intra- and inter-protein surface labeling are described. Ligand-directed protein surface modification strategies have the potential to enhance the induced-proximity pharmacology toolkit and expand the druggable proteome, and this Opinion considers the opportunities and challenges that lie ahead.
Pharmacologically active small organic molecules derived from natural resources are prominent drug candidates due to their inherent structural diversity. Herein, we explored one such bioactive molecule, niloticin, which is a tirucallane-type triterpenoid isolated from the stem barks of Aphanamixis polystachya (Wall.) Parker. After initial screening with other isolated compounds from the same plant, niloticin demonstrated selective cytotoxicity against cervical cancer cells (HeLa) with an IC50 value of 11.64 μM. Whereas the compound exhibited minimal cytotoxicity in normal epithelial cell line MCF-10A, with an IC50 value of 83.31 μM. Subsequently, in silico molecular docking studies of niloticin based on key apoptotic proteins such as p53, Fas, FasL, and TNF β revealed striking binding affinity, reflecting docking scores of -7.2, -7.1, -6.8, and -7.2. Thus, the binding stability was evaluated through molecular dynamic simulation. In a downstream process, the apoptotic capability of niloticin was effectively validated through in vitro fluorimetric assays, encompassing nuclear fragmentation. Additionally, an insightful approach involving surface-enhanced Raman spectroscopy (SERS) re-establishes the occurrence of DNA cleavage during cellular apoptosis. Furthermore, niloticin was observed to induce apoptosis through both intrinsic and extrinsic pathways. This was evidenced by the upregulation of upstream regulatory molecules such as CD40 and TNF, which facilitate the activation of caspase 8. Concurrently, niloticin-induced p53 activation augmented the expression of proapoptotic proteins Bax and Bcl-2 and downregulation of IAPs, leading to the release of cytochrome C and subsequent activation of caspase 9. Therefore, the reflection of mitochondrial-mediated apoptosis is in good agreement with molecular docking studies. Furthermore, the anti-metastatic potential was evidenced by wound area closure and Ki67 expression patterns. This pivotal in vitro assessment confirms the possibility of niloticin being a potent anti-cancer drug candidate, and to the best of our knowledge, this is the first comprehensive anticancer assessment of niloticin in HeLa cells.
TGR5, a receptor that interacts with bile acids on cell surfaces, has become a promising therapeutic target for type II diabetes due to its ability to regulate energy expenditure and blood sugar levels. While several TGR5 agonists have been identified, only a few are currently in clinical trials. This article reviews the promising TGR5 agonists discovered in recent years, highlighting the chemical structure and pharmacological profile of the most effective compounds. With the limited number of effective drugs available for treating type II diabetes, the search for a potent TGR5 agonist with high efficacy and fewer side effects continues. The goal of this article is to provide an overview of the latest advancements in TGR5 agonists and offer insights for the future development of novel, potent TGR5 agonists for diabetes treatment. A noteworthy aspect addressed in the discussion is the common side effect associated with TGR5 agonist treatment – gallbladder filling. The review also explores potential strategies to mitigate this side effect, with the goal of improving the overall safety and tolerability of TGR5-targeted therapies.