Total Flavonoids from Oroxylum indicum Induce Apoptosis via PI3K/Akt/PTEN Signaling Pathway in Liver Cancer

An Overview of Traditional Chinese Medicine in the Treatment After Radical Resection of Hepatocellular Carcinoma

According to the Barcelona Clinic Liver Cancer (BCLC) system, radical resection of early stage primary hepatocellular carcinoma (HCC) mainly includes liver transplantation, surgical resection, and radiofrequency ablation (RFA), which yield 5-year survival rates of about 70-79%, 41.3-69.5%, and 40-70%, respectively. The tumor-free 5-year rate for HCC patients undergoing radical resection only reach up to 13.7 months, so the prevention of recurrence after radical resection of HCC is very important for the prognosis of patients. The traditional Chinese medicine (TCM) takes the approach of multitarget and overall-regulation to treat tumors, it can also independently present the "component-target-pathway" related to a particular disease, and its systematic and holistic characteristics can provide a personalized therapy based on symptoms of the patient by treating the patient as a whole. TCM as postoperative adjuvant therapy after radical resection of HCC in Barcelona Clinic liver cancer A or B stages, and the numerous clinical trials confirmed that the efficacy of TCM in the field of HCC has a significant effect, not only improving the prognosis and quality of life but also enhancing patient survival rate. However, with the characteristics of multi-target, multi-component, and multi-pathway, the specific mechanism of Chinese medicine in the treatment of diseases is still unclear. Because of the positive pharmacological activities of TCM in combating anti-tumors, the mechanism studies of TCM have demonstrated beneficial effects on the regulation of immune function, chronic inflammation, the proliferation and metastasis of liver cancer cells, autophagy, and cell signaling pathways related to liver cancer. Therefore, this article reviews the mechanism of traditional Chinese medicine in reducing the recurrence rate of HCC after radical resection.

Effect of Oroxylum indicum on hepatocellular carcinoma via the P53 and VEGF pathways based on microfluidic chips

BACKGROUND

Hepatocellular carcinoma (HCC), abbreviated as liver cancer, is one of the most common cancers in clinics. HCC has a wider spread and higher incidence due to its high malignancy and metastasis. In HCC, effective strategies to block cancer cell migration, invasion, and neovascularization need to be further studied. Consumption of flavonoid-rich Oroxylum indicum (OI) has been associated with multiple beneficial effects, including anti-inflammatory and anticancer properties, but the potential effects on HCC have not been thoroughly investigated.

OBJECTIVE

In this study, we aimed to reveal the effect of OI on HCC and its potential mechanism through microfluidic technology.

METHODS

We designed microfluidic chips for cell migration, invasion, and neovascularization to evaluate the effect of OI on HepG2 cells. To further explore the mechanism of its anti-liver cancer action, the relevant signaling pathways were studied by microfluidic chips, RT‒qPCR and immunofluorescence techniques. Compared to the control group, cell migration, invasion, and angiogenesis were significantly reduced in each administration group. According to the P53 and VEGF pathways predicted by network pharmacology, RT‒qPCR and immunofluorescence staining experiments were conducted.

RESULTS

The results showed that OI upregulated the expression of Bax, P53 and Caspase-3 and downregulated the expression of Bcl-2 and MDM2. It has been speculated that OI may directly or indirectly induce apoptosis of HepG2 cells by regulating apoptosis-related genes. OI blocks the VEGF signaling pathway by downregulating the expression levels of VEGF, HIF-1α and EGFR and inhibits the migration and invasion of HepG2 cells and the formation of new blood vessels.

CONCLUSION

Our findings suggest that OI may inhibit the migration, invasion, and neovascularization of HepG2 cells, and its regulatory mechanism may be related to the regulation of the P53 and VEGF pathways.

Research Progress of PI3K/PTEN/AKT Signaling Pathway Associated with Renal Cell Carcinoma

Renal cell carcinoma is a common renal malignancy of the urinary system and the most malignant type of kidney cancer. Phosphatidylinositol 3-kinase (PI3K) is an intracellular phosphatidylinositol kinase associated with oncogene products such as v-src and with serine/threonine kinase activity, and its increased activity correlates with the development of several cancers. Protein kinase B (AKT) is a cyclic guanosine phosphate-dependent protein kinase that plays an important role in cell survival and apoptosis. Phosphatase and tensin homolog (PTEN), a newly discovered oncogene in recent years, participates in tumorigenesis and development by competing with tyrosine kinases for common substrates. The product encoded by PTEN was found to negatively regulate the PI3K/Akt signaling pathway, thereby inhibiting cell proliferation and promoting apoptosis. The PI3K/PTEN/AKT signaling pathway has also been identified in several studies as being involved in the development of several malignancies, including renal cell carcinoma. Radiotherapy is currently one of the most effective means of treatment for renal cell carcinoma, whereas it is predisposed to significant tolerance during the course of radiotherapy, thereby leading to treatment failure. Therefore, new treatment options may potentiate the efficiency of renal cell carcinoma treatment. With the development of tumor molecular biology, targeted biological therapy for malignant tumors has gradually become a research hotspot. Given the above research background, this study reviews the application of the PI3K/PTEN/AKT signaling pathway in renal cell carcinoma, aiming to provide more references for the treatment of clinical renal cell carcinoma.

Oroxylum indicum Stem Bark Extract Reduces Tumor Progression by Inhibiting the EGFR-PI3K-AKT Pathway in an In Vivo 4NQO-Induced Oral Cancer Model

OBJECTIVES

Oral squamous cell carcinoma (OSCC) is the predominant type of oral cancer. Its incidence is high in certain geographic regions, and it is correlated with chewing tobacco. Epidermal growth factor receptor (EGFR), induced by tobacco carcinogens, is overexpressed in OSCC, leading to poor prognosis. Thus, EGFR inhibitors are promising agents against OSCC. High cost and toxicity of existing EGFR inhibitors necessitate alternative EGFR-targeted therapy. Here, we tested the antitumor potential of ethyl acetate fraction of an ethnomedicinal tree, Oroxylum indicum stem bark extract (OIEA) in a 4-nitroquinoline-1-oxide (4NQO)-induced oral carcinogenesis model.

METHODS

OIEA was prepared by solvent extraction method, and subsequently its in vitro radical scavenging activities were measured. High-performance liquid chromatography (HPLC) analysis of OIEA was done to identify the constituent active compounds. Hemolytic, trypan blue exclusion, and MTT [3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide] assays were performed in normal and cancer cells to select an optimum dose of OIEA for antitumor activity study in 4NQO-induced oral cancer in F344 rats. Measurement of tumor volume, weight, and cell count was followed by tumor cell cycle analysis and comet and annexin V/Propidium Iodide (PI) assay. Pro-apoptotic markers were detected by western blot testing. Molecular docking was done to predict the interaction between OIEA active component and EGFR or phosphatidylinositol-3-kinase (PI3K), which was further validated biologically. Finally, hepatic and renal function testing and histopathology were performed.

RESULTS

OIEA reduced tumor burden and increased survivability of the tumor-bearing rats significantly as compared to untreated tumor bearers. HPLC revealed oroxylin A as the predominant bioactive component in OIEA. Molecular docking predicted significant binding between oroxylin A and EGFR as well as PI3K, which was confirmed by western blot analysis of in vivo samples. OIEA also ameliorated hepato-, renal- and myelotoxicity induced by 4NQO.

CONCLUSION

OIEA reduces 4NQO-induced OSCC by modulating the EGFR/PI3K/AKT signaling cascade and also ameliorated toxicity in tumor bearers.

Bioassay-Guided Isolation of 2-[p-(2-Carboxyhydrazino)phenoxy]-6-(hydroxymethyl)tetrahydro-2H-pyran-3,4,5-triol from Oroxylum indicum and the Investigation of Its Molecular Mechanism Action of Apoptosis Induction

The leaf crude extract of Oroxylum indicum (L.) Kurz induces genomic DNA fragmentation, comet formation, and the inhibition of cell proliferation in the prostate cancer cell line PC3, as assessed by agarose gel electrophoresis, comet assay and MTT assay, respectively. The bioactive compound was purified through bioassay-guided fractionation using preparative HPLC and MTT assay. The light brown and water-soluble compound was characterized using 1H and 13C nuclear magnetic resonance (NMR), Fourier transform infrared (FT-IR), and electrospray ionization (ESI) mass spectrometry. The compound was identified as a glycosylated hydroquinone derivative, 2-[p-(2-Carboxyhydrazino)phenoxy]-6-(hydroxymethyl) tetrahy-dro-2H-pyran-3,4,5-triol (molecular formula, C13H18N2O8; molecular mass = 330). The identified phytocompound has not been reported earlier elsewhere. Therefore, the common name of the novel anticancer phytocompound isolated from Oroxylum indicum in this current study is oroxyquinone. The half-maximal inhibitory concentration (IC₅₀) of oroxyquinone on PC3 cells was 58.9 µM (95% CI = 54.5 to 63.7 µM). Treatment of PC3 cells with oroxyquinone induced genomic DNA fragmentation and chromatin condensation, increased in the annexin-V positive cells, arrested the cell cycle at S phases, and inhibited the cell migration; as assessed by comet assay, DAPI staining, flow cytometry and a wound healing assay, respectively. On the investigation of the molecular mechanism of the induction of apoptosis, the results indicated that oroxyquinone induced caspase-3 and PARP independent apoptosis but through the p38 pathway and the localization of AIF into the nucleus. The present study identifies a novel anticancer molecule and provides scientific evidence supporting the therapeutic potency of Oroxylum indicum for ethnomedicinal uses.

Systematic Elucidation of the Mechanism of Oroxylum indicum via Network Pharmacology

Oroxylum indicum (O. indicum) is an important traditional Chinese medicine that exerts a wide spectrum of pharmacological activities. However, the pharmacological effect of O. indicum and its mechanism of action have not to be systematically elucidated yet. In this study, the druggability for active compounds of O. indicum was assessed via Traditional Chinese Medicine Systems Pharmacology Database (TCMSP), and the potential drug targets of O. indicum were identified using PharmMapper database. Additionally, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed via WebGestalt. Drug-target-pathway networks were constructed using Cytoscape to give a visual view. Our findings revealed that O. indicum has extremely superb druggability with 41 putative identified target genes. GO, KEGG, and network analyses showed that these targets were associated with inflammatory immunoreactions, cancer, and other biological processes. In summary, O. indicum is predicted to target multiple genes/proteins and pathways that shape a network which can exert systematic pharmacological effects.

Inhibition of cell proliferation and migration by Oroxylum indicum extracts on breast cancer cells via Rac1 modulation

In this study, we investigated how Oroxylum indicum leaf and fruit extracts affect the viability and migration of MCF-7 breast cancer cells and the mechanisms of action responsible for these effects. MCF-7 cells treated with the extracts were examined using the sulforhodamine B, colony formation and caspase 3 activity assays, and by Western blotting. O. indicum extracts were found to inhibit MCF-7 cell growth in a concentration- and time-dependent manner, with 48 h IC₅₀ values of 57.02 ± 2.85 μg/mL and 131.3 ± 19.2 μg/mL for leaf and fruit extracts, respectively. Further, the O. indicum leaf extract caused a reduction in MCF-7 cell viability, induction of MCF-7 cell apoptosis and ROS formation, and an increase in caspase 3 activity. Also, the two extracts inhibited MCF-7 cell migration and reduced both MMP 9 and ICAMP1 gene expression and MMP9 protein expression. Additionally, O. indicum extracts greatly reduced expression of the cell cycle regulatory protein Rac1 in the mevalonate pathway. In summary, O. indicum leaf and fruit extracts reduce breast cancer cell growth, cell viability and cell migration. O. indicum constituents could, therefore, be useful for augmenting the activity of chemotherapeutic drugs employed to treat breast cancer.