Tanshinone IIA targeting cell signaling pathways: a plausible paradigm for cancer therapy.

Natural compounds originating from plants offer a wide range of pharmacological potential and have traditionally been used to treat a wide range of diseases including cancer. Tanshinone IIA (Tan IIA), a bioactive molecule found in the roots of the Traditional Chinese Medicine (TCM) herb Salvia miltiorrhiza, has been shown to have remarkable anticancer properties through several mechanisms, such as inhibition of tumor cell growth and proliferation, metastasis, invasion, and angiogenesis, as well as induction of apoptosis and autophagy. It has demonstrated excellent anticancer efficacy against cell lines from breast, cervical, colorectal, gastric, lung, and prostate cancer by modulating multiple signaling pathways including PI3K/Akt, JAK/STAT, IGF-1R, and Bcl-2-Caspase pathways. This review focuses on the role of Tan IIA in the treatment of various cancers, as well as the underlying molecular mechanisms.

Curcumin and Plumbagin Synergistically Target the PI3K/Akt/mTOR Pathway: A Prospective Role in Cancer Treatment.

Cancer development is associated with the deregulation of various cell signaling pathways brought on by certain genetic and epigenetic alterations. Therefore, novel therapeutic strategies have been developed to target those pathways. The phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) (PI3K/Akt/mTOR) pathway is one major deregulated pathway in various types of cancer. Several anticancer drug candidates are currently being investigated in preclinical and/or clinical studies to target this pathway. Natural bioactive compounds provide an excellent source for anticancer drug development. Curcumin and plumbagin are two potential anticancer compounds that have been shown to target the PI3K/Akt/mTOR pathway individually. However, their combinatorial effect on cancer cells is still unknown. This study aims to investigate the synergistic effect of these two compounds on the PI3K/Akt/mTOR pathway by employing a sequential molecular docking and molecular dynamics (MD) analysis. An increase in binding affinity and a decrease in inhibition constant have been observed when curcumin and plumbagin were subjected to sequential docking against the key proteins PI3K, Akt, and mTOR. The MD simulations and molecular mechanics combined with generalized Born surface area (MM-GBSA) analyses validated the target proteins' more stable conformation when interacting with the curcumin and plumbagin combination. This indicates the synergistic role of curcumin and plumbagin against cancer cells and the possible dose advantage when used in combination. The findings of this study pave the way for further investigation of their combinatorial effect on cancer cells in vitro and in vivo models.

Targeting Glutaminase by Natural Compounds: Structure-Based Virtual Screening and Molecular Dynamics Simulation Approach to Suppress Cancer Progression.

Cancer cells change their glucose and glutamine (GLU) metabolism to obtain the energy required to continue growing. Glutaminase (GLS) plays a crucial role in promoting cell metabolism for cancer cell growth; targeting GLU metabolism by inhibiting GLS has attracted interest as a potential cancer management strategy. Herein, we employed a sequential screening of traditional Chinese medicine (TCM) database followed by drug-likeness and molecular dynamics simulations against the active site of GLS. We report 12 potent compounds after screening the TCM database against GLS, followed by a drug-likeness filter with Lipinski and Veber rule criteria. Among them, ZINC03978829 and ZINC32296657 were found to have higher binding energy (BE) values than the control compound 6-Diazo-5-Oxo-L-Norleucine, with BEs of -9.3 and -9.7 kcal/mol, respectively, compared to the BE of 6-Diazo-5-Oxo-L-Norleucine (-4.7 kcal/mol) with GLS. Molecular dynamics simulations were used to evaluate the results further, and a 100 ns MD simulation revealed that the hits form stable complexes with GLS and formed 2-5 hydrogen bond interactions. This study indicates that these hits might be employed as GLS inhibitors in the battle against cancer. However, more laboratory tests are a prerequisite to optimize them as GLS inhibitors.

Identification of Potential Poly (ADP-Ribose) Polymerase-1 Inhibitors Derived from Rauwolfia serpentina: Possible Implication in Cancer Therapy.

Poly (ADP-ribose) polymerase-1 (PARP-1) has been recognized as a prospective target for the development of novel cancer therapeutics. Several PARP-1 inhibitors are currently being considered for anticancer drug development and clinical investigation. Lately, natural compounds seem to be excellent alternative drug candidates for cancer treatment. Rauwolfia serpentina is a medicinal plant traditionally used in Indian subcontinents to treat various diseases. This study has been designed to identify the bioactive compounds derived from R. serpentina for possible binding and inhibition of PARP-1 using the molecular docking approach. Thirteen compounds were found to interact with the target with a binding affinity greater than the value of -9.0 kcal/mol. After screening the physicochemical properties, only 5 ligands (ajmalicine, yohimbine, isorauhimbine, rauwolscine, and 1,2-dihydrovomilenine) were found to obey all the parameters of Lipinski's rule of five, showed maximum drug-likeness, and possess no significant toxicity. These ligands displayed strong interactions with target PARP-1 via several hydrogen bonds and hydrophobic interactions. Therefore, these identified compounds derived from R. serpentina can be considered for drug development against cancer-targeting PARP-1.

Elucidating Antiangiogenic Potential of Rauwolfia serpentina: VEGFR-2 Targeting-Based Molecular Docking Study.

Angiogenesis plays a critical role in tumorigenesis as it provides the necessary blood supply to the newly grown solid tumor. It helps maintain the tumor microenvironment, promotes tumor development, progression, and metastasis. The vascular epithelial growth factor (VEGF), interacting with the tyrosine kinase receptor VEGFR-2 on endothelial cells, exerts its proangiogenic activity. Hence, targeting the VEGFR-2 signaling is considered a promising strategy to inhibit angiogenesis and thus cancer treatment. This study aims to identify the bioactive compounds derived from the medicinal herb Rauwolfia serpentina that effectively binds with VEGFR-2. The bioactive compounds of R. serpentina were first screened for their physicochemical properties using the DataWarrior program (version 5.5.0). Finally, 17 compounds that obeyed Lipinski's rule of five and showed good drug-likeness were selected for molecular docking studies. Molecular docking results showed that the ligands ajmalicidine, 1, 2-dihydrovomilenine, rauwolscine, yohimbine, ajmaline, and papaverine interact strongly with the target VEGFR-2 receptor. Hydrogen bonds and hydrophobic interactions stabilized the interactions of these compounds with VEGFR-2. These compounds showed favourable drug-like properties and possess no significant toxicity. Therefore, the findings of this study indicate that the compounds derived from R. serpentina can be considered for the development of antiangiogenic drug candidates by targeting VEGFR-2.

Prospective therapeutic potential of Tanshinone IIA: An updated overview.

In the past decades, the branch of complementary and alternative medicine based therapeutics has gained considerable attention worldwide. Pharmacological efficacy of various traditional medicinal plants, their products and/or product derivatives have been explored on an increasing scale. Tanshinone IIA (Tan IIA) is a pharmacologically active lipophilic component of Salvia miltiorrhiza extract. Tan IIA shares a history of high repute in Traditional Chinese Medicine. Reckoning with these, the present review collates the pharmacological properties of Tan IIA with a special emphasis on its therapeutic potential against diverse diseases including cardiovascular diseases, cerebrovascular diseases, cancer, diabetes, obesity and neurogenerative diseases. Further, possible applications of various therapeutic preparations of Tan IIA were discussed with special emphasis on nano-based drug delivery formulations. Considering the tremendous advancement in the field of nanomedicine and the therapeutic potential of Tan IIA, the convergence of these two aspects can be foreseen with great promise in clinical application.