Chrysophanol Regulates Cell Death, Metastasis, and Reactive Oxygen Species Production in Oral Cancer Cell Lines

Chrysophanol Induces Cell Death and Inhibits Invasiveness through Alteration of Calcium Levels in HepG2 Human Liver Cancer Cells

OBJECTIVE

To investigate the effect of chrysophanol, a phytochemical derived from Radix et Rhizoma Rhei on HepG2 liver cancer cells.

METHODS

HepG2 cell line was treated with different concentrations chrysophanol (0-100 μmol/L) for 24 h. The cell counting kit 8 assay was employed to assess cell viability. Intracellular calcium levels were examined using Fluo-4 AM and Mag-fluo-4 AM staining, followed by flow cytometry analysis. Mitochondrial membrane potential was measured with JC-1 assay kit. Additionally, the expressions of key proteins such as p-JNK, Bax, cytochrome c (Cyt C), cleaved caspase-3 (cCaspase-3), and caspase-8 were analyzed by Western blot. The inhibitory effects of chrysophanol on the invasion of cells were determined using a Transwell assay. Analysis of invasiveness was conducted by wound healing assay.

RESULTS

Chrysophanol significantly reduced the proliferation of HepG2 liver cancer cells by affecting intracellular calcium distribution, diminishing mitochondrial membrane potential, and enhancing the expressions of p-JNK, Bax, Cyt C, cCaspase-3, and caspase-8 in the groups treated with 75 or 100 μmol/L chrysophanol compared to the control group (P<0.05). Additionally, 75 and 100 μmol/L chrysophanol exhibited inhibitory effects on cell migration and wound healing.

CONCLUSION

Chrysophanol demonstrates potential against HepG2 liver cancer cells, suggesting its potential use as a therapeutic agent for liver cancer treatment.

Advances in Small Molecular Agents against Oral Cancer

Oral cancer is a common malignancy with a high mortality rate. Although surgery is the best treatment option for patients with cancer, this approach is ineffective for advanced metastases. Molecular agents are irreplaceable in preventing and treating distant metastases. This review aims to summarise the molecular agents used for the treatment of oral cancer in the last decade and describe their sources and curative effects. These agents are classified into phenols, isothiocyanates, anthraquinones, statins, flavonoids, terpenoids, and steroids. The mechanisms of action of these agents include regulating the expression of cell signalling pathways and related proteases to affect the proliferation, autophagy, migration, apoptosis, and other biological aspects of oral cancer cells. This paper may serve as a reference for subsequent studies on the treatment of oral cancer.

Chrysophanol Suppresses Cell Growth via mTOR/PPAR-α Regulation and ROS Accumulation in Cultured Human Tongue Squamous Carcinoma SAS Cells

Oral cancer, a type of head and neck cancer, can pose a significant risk of death unless diagnosed and treated early. Alternative treatments are urgently needed owing to the high mortality rate, limitations of conventional treatments, and many complications. The anthraquinone compound chrysophanol acts as a tumor suppressor on some types of cancer cells. To date, it has not been clarified how chrysophanol affects human tongue squamous carcinoma. This study was aimed to examine the effects of chrysophanol on oral cancer treatment. The results show that chrysophanol caused cell death, reduced the expression of the mammalian target of rapamycin (mTOR)/peroxisome proliferator-activated receptor-alpha (PPAR-α), and increased reactive oxygen species (ROS) production. We also used two ion chelators, deferoxamine (DFO) and liproxstatin-1 (Lipro), to further determine whether chrysophanol inhibits cell growth and regulates mTOR/PPAR-α expression and ROS production, both of which are involved in iron homeostasis. The results show that DFO and Lipro reversed the increase in cell death, downregulation of mTOR/PPAR-α, and decrease in ROS accumulation. In conclusion, chrysophanol inhibits the growth of oral squamous cell carcinoma cells by modulating mTOR/PPAR-α and by causing ROS accumulation.

Network pharmacology reveals potential functional components and underlying molecular mechanisms of Andrographis paniculata in esophageal cancer treatment

Antitumor and antimetastatic effects of the medicinal herb Andrographis paniculata (AP) in esophageal cancer (EC) have been previously reported. In this study, we aimed to uncover the potential functional components and the underlying molecular mechanisms of AP in EC treatment using network pharmacology and experimental validation. Twenty-two potential active AP compounds against EC were revealed, including the antitumor/antiinflammatory compounds panicolin, moslosooflavone, and deoxyandrographiside. Epidermal growth factor receptor (EGFR), signal transducer and activator of transcription 3 (STAT3), RAC-alpha serine/threonine-protein kinase (AKT1), prostaglandin-endoperoxide synthase 2 (PTGS2), chemokine (C-X-C motif) ligand 8 (CXCL8), phosphatidylinositol 4,5-bisphosphate 3-kinase subunit alpha (PIK3CA), and toll-like receptor 4 (TLR4) were most highly ranked among the predicted targets of AP in EC treatment and may play important roles in the anti-EC effects of AP. KEGG pathway analysis revealed the enrichment of multiple cancer-related pathways and signaling pathways. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blotting validation showed that overnight treatment with 850.3 μg/ml of AP water extract significantly reduced the mRNA expressions of EGFR and AKT in human EC-109 cells. The presence of panicolin and moslosooflavone in the AP water extract samples were confirmed using LC-MS against reference standards. This study has comprehensively revealed for the first time the potential functional components of AP in EC and explored the underlying molecular mechanisms. Future studies should characterize the potential pharmacological properties of the other highly ranked yet understudied compounds in AP detected.

Role of the Inflammatory Response of RAW 264.7 Cells in the Metastasis of Novel Cancer Stem-Like Cells

Background and objectives: Tumor progression and the immune response are intricately linked. Additionally, the presence of macrophages in the microenvironment is essential for carcinogenesis, but regulation of the polarization of M1- and M2-like macrophages and their role in metastasis remain unclear. Based on previous studies, both reactive oxygen species (ROS) and the endoplasmic reticulum (ER) are emerging as key players in macrophage polarization. While it is known that cancers alter macrophage inflammatory responses to promote tumor progression, there is limited knowledge regarding how they affect the macrophage-dependent innate host defense. Materials and methods: We detected the levels of ROS, the ability of chemotaxis, the expressions of markers of M1-/M2-like macrophages in RAW264.7 in presence of T2- and T2C-conditioned medium. Results: The results of this study indicated that ROS levels were decreased in RAW 264.7 cells when cultured with T2C-conditioned medium, while there was an improvement in chemotaxis abilities. We also found that the M2-like macrophages were characterized by an elongated shape in RAW 264.7 cells cultured in T2C-conditioned medium, which had increased CD206 expression but decreased expression of CD86 and inducible nitric oxide synthase. Suppression of ER stress shifted polarized M1-like macrophages toward an M2-like phenotype in RAW 264.7 cells cultured in T2C-conditioned medium. Conclusions: Taken together, we conclude that the polarization of macrophages is associated with the alteration of cell shape, ROS accumulation, and ER stress.

Phytochemicals as Potential Chemopreventive and Chemotherapeutic Agents for Emerging Human Papillomavirus-Driven Head and Neck Cancer: Current Evidence and Future Prospects

Head and neck cancer (HNC) usually arises from squamous cells of the upper aerodigestive tract that line the mucosal surface in the head and neck region. In India, HNC is common in males, and it is the sixth most common cancer globally. Conventionally, HNC attributes to the use of alcohol or chewing tobacco. Over the past four decades, portions of human papillomavirus (HPV)-positive HNC are increasing at an alarming rate. Identification based on the etiological factors and molecular signatures demonstrates that these neoplastic lesions belong to a distinct category that differs in pathological characteristics and therapeutic response. Slow development in HNC therapeutics has resulted in a low 5-year survival rate in the last two decades. Interestingly, HPV-positive HNC has shown better outcomes following conservative treatments and immunotherapies. This raises demand to have a pre-therapy assessment of HPV status to decide the treatment strategy. Moreover, there is no HPV-specific treatment for HPV-positive HNC patients. Accumulating evidence suggests that phytochemicals are promising leads against HNC and show potential as adjuvants to chemoradiotherapy in HNC. However, only a few of these phytochemicals target HPV. The aim of the present article was to collate data on various leading phytochemicals that have shown promising results in the prevention and treatment of HNC in general and HPV-driven HNC. The review explores the possibility of using these leads against HPV-positive tumors as some of the signaling pathways are common. The review also addresses various challenges in the field that prevent their use in clinical settings.

Interleukin-6 and Interleukin-8 Regulate STAT3 Activation Migration/Invasion and EMT in Chrysophanol-Treated Oral Cancer Cell Lines

The tumor microenvironment plays a critical role in the control of metastasis. The epithelial–mesenchymal transition (EMT) is strongly associated with tumor metastasis, and consists of several protein markers, including E-cadherin and vimentin. We discovered that chrysophanol causes oral cancer cell apoptosis and the inhibition of migration/invasion and EMT. However, the detailed mechanisms of chrysophanol and its role in oral cancer with respect to the tumor microenvironment remain unknown. In the clinic, proinflammatory cytokines, such as IL-6 and IL-8, exhibit a higher expression in patients with oral cancer. However, the effect of chrysophanol on the production of IL-6 and IL-8 is unknown. We evaluated the expression of IL-6 and IL-8 in human SAS and FaDu oral cancer cell lines in the presence or absence of chrysophanol. The migration and invasion abilities were also determined using a Boyden chamber assay. Our results showed that treatment with chrysophanol significantly decreased the expression of IL-6 and IL-8, as well as the invasion ability of oral cancer cells. Moreover, chrysophanol also attenuated the EMT by increasing the expression of E-cadherin and reducing the expression of vimentin. Mechanistically, chrysophanol inhibited IL-6- and IL-8-induced invasion and STAT3 phosphorylation. IL-6 and IL-8 promote EMT and cell invasion, which is potentially related to the STAT3 signaling pathway in oral cancer. These findings provide insight into new aspects of chrysophanol activity and may contribute to the development of new therapeutic strategies for oral cancer.

Chrysophanol inhibits the osteoglycin/mTOR and activats NF2 signaling pathways to reduce viability and proliferation of malignant meningioma cells

Chrysophanol shows promising antitumor activity, but how it may work against malignant meningioma is poorly understood. In addition, osteoglycin (OGN) may help mediate the antitumor effects of chrysophanol; thus, this study investigated the potential antitumor mechanism of chrysophanol in malignant meningioma cultures. Meningioma cell line HBL-52 were incubated with varying doses of chrysophanol (0-90 μM) for different time points, and osteoglycin (OGN) was overexpressed or inhibited in some cell cultures to assess its roles. Cell viability was quantified using the CCK8 assay and colony formation assays, while effects on cell cycle distribution and apoptotic rates were examined by flow cytometry and enzyme-linked immunosorbent assays (ELISA) to detect histone DNA levels. Caspase-3 and -9 activities were detected by related commercial kits. Protein expression was assessed using Western blotting. Chrysophanol significantly reduced HBL-52 cell viability, based on reduced colony formation, and proliferation, based on low levels of bromodeoxyuridine incorporation. Annexin V/propidium iodide staining revealed a 30% increase in apoptotic cells at 90 μM chrysophanol (33.7% vs 3.3% in control cultures). Chrysophanol treatment greatly decreased the Bcl-2/Bax expression ratio and increased the expressions of cleaved caspase-3 and -9, and the activities of caspase-3 and -9. Chrysophanol blocked cells in G1 phase and inhibited the OGN/mTOR signaling cascade, but activated neurofibromatosis 2 (NF2) cascade. OGN overexpression activated mTOR, down-regulated NF2, and partially reversed growth inhibition by chrysophanol. Chrysophanol may be useful as a treatment against malignant meningioma by inhibiting OGN/mTOR signaling and activating NF2 signaling.

Chrysophanol Inhibits the Progression of Diabetic Nephropathy via Inactivation of TGF-β Pathway

Background

Diabetic nephropathy (DN) is a common form of diabetic complication which threatens the health of patients with diabetes. It has been reported that chrysophanol (CHR) can alleviate the progression of diabetes; however, the role of CHR in DN remains unclear.

Methods

To mimic DN in vitro, human podocytes (AB8/13 cells) were treated with high glucose (HG). Meanwhile, Western blot was performed to detect protein expressions. CCK-8 assay was used to test cell viability and cell proliferation was detected by Ki-67 staining. In addition, flow cytometry was performed to investigate cell apoptosis and cycle and cell migration was tested by transwell assay. Moreover, in vivo model of DN was established to detect the effect of CHR on DN in vivo.

Results

HG-induced AB8/13 cell growth inhibition was significantly rescued by CHR. In addition, HG notably promoted the migration of AB8/13 cells, while this phenomenon was obviously reversed by CHR. Moreover, CHR inhibited the progression of DN via inactivation of TGF-β/EMT axis. Furthermore, CHR alleviated the symptom of DN in vivo.

Conclusion

CHR significantly alleviated the progression of DN via inactivation of TGF-β/EMT signaling in vitro and in vivo. Our findings were helpful to uncover the mechanism by which CHR regulates DN, as well as inspire the development of novel therapy against DN.

Traditional Herbal Medicine Mediated Regulations during Head and Neck Carcinogenesis

Head and neck squamous cell carcinoma (HNSCC) is one of the most prevalent neoplasms worldwide. It is well recognized that environmental challenges such as smoking, viral infection and alcohol consumption are key factors underlying HNSCC pathogenesis. Other than major clinical interventions (e.g., surgical resection, chemical and radiotherapy) that have been routinely practiced over years, adjuvant anticancer agents from Traditional Herbal Medicine (THM) are proposed, either alone or together with conventional therapies, to be experimentally effective for improving treatment efficacy in different cancers including HNSCCs. At a cellular and molecular basis, THM extracts could modulate different malignant indices via distinct signaling pathways and provide better control in HNSCC malignancy and its clinical complications such as radiotherapy-induced xerostomia/oral mucositis. In this article, we aim to systemically review the impacts of THM in regulating HNSCC tumorous identities and its potential perspective for clinical use.

Role of Chrysophanol in Epithelial-Mesenchymal Transition in Oral Cancer Cell Lines via a Wnt-3-Dependent Pathway

Oral cancer belongs to the group of head and neck cancers. If not diagnosed or treated early, it can be life threatening. Epithelial-mesenchymal transition (EMT) plays an important role in tumor formation and progression. An increase in the presence of the EMT phenotype causes tumor cell proliferation, migration, invasion, and poor prognosis. Therefore, attenuating carcinogenesis via EMT inhibition is a good strategy. Herein, we will determine the pharmacological effects of chrysophanol on the EMT in FaDu cells. To analyze EMT, we detected the expression EMT markers, including α-SMA, β-catenin, vimentin, N-cadherin, E-cadherin, phospho-GSK-3β, and nuclear translocations of p65 and β-catenin by western blotting. Additionally, accumulating evidence indicates that reactive oxygen species (ROS) mediate EMT. Our results showed that the level of ROS was significantly increased after chrysophanol treatment. We further speculated that chrysophanol-mediated EMT and metastasis are involved in the Wnt-3-dependent signaling pathway. The inhibition of the EMT phenotype and metastasis and accumulation of ROS caused by chrysophanol was reversed by treatment with the Wnt-3 agonist Bml 284. Therefore, our findings indicated that chrysophanol altered EMT formation, ROS accumulation, and metastasis via the Wnt-3-dependent signaling pathway.