(−)-β-hydrastine suppresses the proliferation and invasion of human lung adenocarcinoma cells by inhibiting PAK4 kinase activity

PDZ and LIM Domain-Encoding Genes: Their Role in Cancer Development

PDZ-LIM family proteins (PDLIMs) are a kind of scaffolding proteins that contain PDZ and LIM interaction domains. As protein-protein interacting molecules, PDZ and LIM domains function as scaffolds to bind to a variety of proteins. The PDLIMs are composed of evolutionarily conserved proteins found throughout different species. They can participate in cell signal transduction by mediating the interaction of signal molecules. They are involved in many important physiological processes, such as cell differentiation, proliferation, migration, and the maintenance of cellular structural integrity. Studies have shown that dysregulation of the PDLIMs leads to tumor formation and development. In this paper, we review and integrate the current knowledge on PDLIMs. The structure and function of the PDZ and LIM structural domains and the role of the PDLIMs in tumor development are described.

Nano-Drug Delivery Systems Entrapping Natural Bioactive Compounds for Cancer: Recent Progress and Future Challenges

Cancer is a prominent cause of mortality globally, and it becomes fatal and incurable if it is delayed in diagnosis. Chemotherapy is a type of treatment that is used to eliminate, diminish, or restrict tumor progression. Chemotherapeutic medicines are available in various formulations. Some tumors require just one type of chemotherapy medication, while others may require a combination of surgery and/or radiotherapy. Treatments might last from a few minutes to many hours to several days. Each medication has potential adverse effects associated with it. Researchers have recently become interested in the use of natural bioactive compounds in anticancer therapy. Some phytochemicals have effects on cellular processes and signaling pathways with potential antitumor properties. Beneficial anticancer effects of phytochemicals were observed in both in vivo and in vitro investigations. Encapsulating natural bioactive compounds in different drug delivery methods may improve their anticancer efficacy. Greater in vivo stability and bioavailability, as well as a reduction in undesirable effects and an enhancement in target-specific activity, will increase the effectiveness of bioactive compounds. This review work focuses on a novel drug delivery system that entraps natural bioactive substances. It also provides an idea of the bioavailability of phytochemicals, challenges and limitations of standard cancer therapy. It also encompasses recent patents on nanoparticle formulations containing a natural anti-cancer molecule.

Interfering with pak4 Protein Expression Affects Osteosarcoma Cell Proliferation and Migration

Purpose

A number of studies have discovered various roles of PAK4 in human tumors, including osteosarcoma. However, the exact role of PAK4 in osteosarcoma and its mechanism have yet to be determined. Therefore, this study focused on interrogating the PAK4 effect on the proliferation and migration ability of osteosarcoma and its underlying mechanisms.

Materials and Methods

Western blot and QRT-PCR were utilized to quantify the PAK4 relative protein and mRNA levels. To measure cellular viability and mobility, the MTT and wound-healing assays were preferred.

Results

With the adenovirus-mediated overexpression of PAK4, the proliferation and migration of U2-OS and MG-63 osteosarcoma cells were stimulated. Furthermore, a liposome-mediated knockout of PAK4 will inhibit osteosarcoma cells from proliferating. In terms of mechanism, we observed the positive correlation of PAK4 expression with expression of P21, CyclinD1, CyclinE1, CDK2, and CDK6, which drives G0/G1 to the G2/M phase transition. PAK4 can also activate Erk expression in OS cells and induce EMT.

Conclusion

Interfering with PAK4 protein expression has been shown to affect osteosarcoma proliferation and migration.

Targeting Aberrant Expression of STAT3 and AP-1 Oncogenic Transcription Factors and HPV Oncoproteins in Cervical Cancer by Berberis aquifolium

Background: Present study examines phytochemical preparation that uses berberine's plant source B. aquifolium root for availability of similar anti-cervical cancer (CaCx) and anti-HPV activities to facilitate repurposing of the B. aquifolium based drug in the treatment of CaCx. Purpose: To evaluate therapeutic potential of different concentrations of ethanolic extract of B. aquifolium root mother tincture (BAMT) against HPV-positive (HPV16: SiHa, HPV18: HeLa) and HPV-negative (C33a) CaCx cell lines at molecular oncogenic level. Materials and Methods: BAMT was screened for anti-proliferative activity by MTT assay. Cell cycle progression was analyzed by flowcytometry. Then, the expression level of STAT3, AP-1, HPV E6 and E7 was detected by immunoblotting, whereas nuclear localization was observed by fluorescence microscopy. Phytochemicals reportedly available in BAMT were examined for their inhibitory action on HPV16 E6 by in silico molecular docking. Results: BAMT induced a dose-dependent decline in CaCx cell viability in all cell types tested. Flowcytometric evaluation of BAMT-treated cells showed a small but specific cell growth arrest in G1-phase. BAMT-treatment resulted in reduced protein expression of key transcription factors, STAT3 with a decline of its active form pSTAT3 (Y705); and components of AP-1 complex, JunB and c-Jun. Immunocytochemistry revealed that BAMT did not prevent the entry of remnant active transcription factor to the nucleus, but loss of overall transcription factor activity resulted in reduced availability of transcription factors in the cancer cells. These changes were accompanied by gradual loss of HPV E6 and E7 protein in BAMT-treated HPV-positive cells. Molecular docking of reported active phytochemicals in B. aquifolium root was performed, which indicated a potential interference of HPV16 E6's interaction with pivotal cellular targets p53, E6AP or both by constituent phytochemicals. Among these, berberine, palmatine and magnoflorine showed highest E6 inhibitory potential. Conclusion: Overall, BAMT showed multi-pronged therapeutic potential against HPV infection and cervical cancer and the study described the underlying molecular mechanism of its action.

Goldenseal (Hydrastis canadensis L.) and its active constituents: A critical review of their efficacy and toxicological issues

Goldenseal (Hydrastis canadensis L.) is a medicinal plant widely used in various traditional systems of medicine and as a food supplement. It has been traditionally used by Native Americans as a coloring agent and as medicinal remedy for common diseases and conditions like wounds, digestive disorders, ulcers, skin and eye ailments, and cancer. Over the years, goldenseal has become a popular food supplement in the USA and other regions. The rhizome of this plant has been used for the treatment of a variety of diseases including, gastrointestinal disorders, ulcers, muscular debility, nervous prostration, constipation, skin and eye infections, cancer, among others. Berberine is one of the most bioactive alkaloid that has been identified in different parts of goldenseal. The goldenseal extract containing berberine showed numerous therapeutic effects such as antimicrobial, anti-inflammatory, hypolipidemic, hypoglycemic, antioxidant, neuroprotective (anti-Alzheimer's disease), cardioprotective, and gastrointestinal protective. Various research finding suggest the health promoting effects of goldenseal components and their extracts. However, few studies have also suggested the possible neurotoxic, hepatotoxic and phototoxic activities of goldenseal extract and its alkaloids. Thus, large randomized, double-blind clinical studies need to be conducted on goldenseal supplements and their main alkaloids to provide more evidence on the mechanisms responsible for the pharmaceutical activity, clinical efficacy and safety of these products. Thus, it is very important to review the scientific information about goldenseal to understand about the current scenario.

Effects of PAK4/LIMK1/Cofilin-1 signaling pathway on proliferation, invasion, and migration of human osteosarcoma cells

Purpose

To explore the effects of PAK4/LIMK1/Cofilin‐1 signaling pathway on the proliferation, invasion, and migration of human osteosarcoma cells.

Methods

The expression of PAK4/LIMK1/Cofilin‐1 was detected by immunohistochemistry in osteosarcoma tissues. The osteosarcoma cell line MG63 was transfected and divided into Mock, Control siRNA, si‐PAK4, LIMK1, and si‐PAK4+LIMK1 groups. Then, the cellular biological features of MG63 cells were detected by CCK‐8, wound‐healing, Transwell, and flow cytometry methods. The relationship of PAK4 and LIMK1 was performed by co‐immunoprecipitation test, and the protein expression of PAK4/LIMK1/Cofilin‐1 was determined by Western blotting. Finally, the effect of PAK4 on the growth of osteosarcoma was verified by subcutaneous transplantation model of osteosarcoma in nude mice.

Results

The expression of PAK4/LIMK1/Cofilin‐1 in both osteosarcoma tissues and cells was up‐regulated. Positive PAK4, LIMK1, and Cofilin‐1 expressions in osteosarcoma were associated with the clinical stage, distant metastasis, and tumor grade. The MG63 cell viability, migration, and invasion, as well as the expression of PAK4, p‐LIMK/LIMK, and p‐Cofilin‐1/Cofilin‐1, were restrained by the knock down of PAK4 while it promoted apoptosis. PAK4 silencing also suppressed the growth of subcutaneous transplanted tumor in nude mice. Co‐immunocoprecipitation showed that LIMK and PAK4 protein can form complex in osteosarcoma cells. Besides, LIMK1 overexpression reversed the inhibition effect of PAK4 siRNA on the growth of osteosarcoma cells.

Conclusion

The expression of PAK4/LIMK1/Cofilin‐1 pathway in osteosarcoma tissues was up‐regulated. Thus, PAK4 inhibition may restrict the osteosarcoma cell proliferation, invasion, and migration but promote its apoptosis via decreasing the activity of LIMK1/Cofilin‐1 pathway.

Studies on asymmetric total synthesis of (-)-β-hydrastine via a chiral epoxide ring-opening cascade cyclization strategy

Herein, facile and enantioselective approaches to synthesize the core phthalide tetrahydroisoquinoline scaffold of (-)-β-hydrastine via both a CF3COOH-catalyzed (86% ee) and KHMDS-catalyzed (78% ee) epoxide ring-opening/transesterification cascade cyclization from chiral epoxide under very mild conditions are described. The key elements include a highly enantioselective epoxidation using the Shi ketone catalyst and an intramolecular CF3COOH-catalyzed cascade cyclization in one pot, and a late-stage C-3' epimerization under MeOK/MeOH conditions as the key steps to achieve the first total synthesis of (-)-β-hydrastine (up to 81% ee).

Molecular dynamics simulation and QM/MM calculation reveal the selectivity mechanism of type I 1/2 kinase inhibitors: the effect of intramolecular H-bonds and conformational restriction for improved selectivity

Understanding the selectivity mechanisms of inhibitors towards highly similar proteins is extremely important work on the way to a new drug. Here, we aim to reveal the selectivity mechanisms of type I 1/2 kinase inhibitors towards p21-activated kinase (PAK4) and mitogen-activated protein kinase kinase kinase 14 (MAP3K14, NIK). PAK4, belonging to the serine/threonine protein kinases, is involved in cell signaling pathways and controls cellular functions and has received attention as an attractive drug target. The high sequence identity between PAK4 and NIK makes it challenging to design selective PAK4 inhibitors. In this work, computational methods including protein comparison, molecular docking, QM/MM, molecular dynamics simulations, and density functional theory (DFT) calculation were employed to explore the binding mechanisms of selective inhibitors against NIK and PAK4. The simulation results revealed the crucial factors accounting for selective inhibition of PAK4 over NIK, including different protein-ligand interactions, the positions and conformations of key residues, and the ligands flexibilities. This study will shed light on understanding the selectivity mechanisms of PAK4 and NIK inhibitors.

An Acid-Catalyzed Epoxide Ring-Opening/Transesterification Cascade Cyclization to Diastereoselective Syntheses of (±)-β-Noscapine and (±)-β-Hydrastine

An acid-catalyzed stereoselective epoxide ring-opening/intramolecular transesterification cascade cyclization reaction and N-Boc deprotection was found to be a successful strategy to construct the phthalide tetrahydroisoquinoline skeleton in one pot. Based on this strategy, the unified and highly diastereoselective routes for the total syntheses of (±)-β-Noscapine and (±)-β-Hydrastine were exploited.

Advances in the 1-phenanthryl-tetrahydroisoquinoline series of PAK4 inhibitors: potent agents restrain tumor cell growth and invasion

A new series of novel 1-phenanthryl-tetrahydroisoquinoline derivatives were designed, synthesized and biologically evaluated for their PAK4 inhibitory activities and anti-proliferative effects against three cancer cell lines A549, MCF-7 and HT-1080. Among them, compound 12a exhibited the most potent inhibitory activity against PAK4 with an IC50 value of 0.42 μM. Moreover, this compound inhibited the invasion of A549 tumor cells by regulating the PAK4-LIMK1-cofilin signaling pathway in vitro, and exhibited anti-tumor activity in vivo in the A549 tumor xenograft model. To further evaluate the binding mode of 12a with PAK4, the biotinylated 12a derivative has been synthesized and it was used for immunoprecipitation assay. Intriguingly, our observations suggest that 12a interacts with both the N- and C-termini of PAK4.

Gene-set Analysis with CGI Information for Differential DNA Methylation Profiling

DNA methylation is a well-established epigenetic biomarker for many diseases. Studying the relationships among a group of genes and their methylations may help to unravel the etiology of diseases. Since CpG-islands (CGIs) play a crucial role in the regulation of transcription during methylation, including them in the analysis may provide further information in understanding the pathogenesis of cancers. Such CGI information, however, has usually been overlooked in existing gene-set analyses. Here we aimed to include both pathway information and CGI status to rank competing gene-sets and identify among them the genes most likely contributing to DNA methylation changes. To accomplish this, we devised a Bayesian model for matched case-control studies with parameters for CGI status and pathway associations, while incorporating intra-gene-set information. Three cancer studies with candidate pathways were analyzed to illustrate this approach. The strength of association for each candidate pathway and the influence of each gene were evaluated. Results show that, based on probabilities, the importance of pathways and genes can be determined. The findings confirm that some of these genes are cancer-related and may hold the potential to be targeted in drug development.