Suppressive function of low-dose deguelin on the invasion of oral cancer cells by downregulating tumor necrosis factor alpha-induced nuclear factor-kappa B signaling

Antiproliferative Activities and SwissADME Predictions of Physicochemical Properties of Carbonyl Group-Modified Rotenone Analogues

Rotenone is a naturally occurring compound shown to exhibit antiproliferative activity against various cancer cell lines, indicating its potential as a lead anticancer agent. However, its toxicity against normal cells has prompted further investigation and chemical modifications. In this study, a library of carbonyl group-modified rotenone derivatives was synthesized and evaluated for their antiproliferative activities against MCF-7 breast cancer cells, A549 human lung carcinoma cells, and HCT116 human colorectal cancer cells using 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) assay. The results showed several promising compounds that inhibited cell proliferation. Specifically, the oxime and alcohol rotenone derivatives exhibited antiproliferative activities against all 3 cancer cell lines, while the ethoxy, carbamate, and alkene derivatives are selective against MCF-7 (IC50 =5.72 μM), HCT116 (IC50 =8.86 μM), and A549 (IC50 =0.11 μM), respectively. SwissADME analysis showed that the physicochemical properties and drug-likeness of the synthesized rotenone derivatives were within the set limits, suggesting the favorable characteristics of these compounds for drug development. The findings obtained in this work highlight the potential of rotenone derivatives as promising chemotherapeutic candidates.

Inhibitory Effects of B-, C-, and E-Ring-Truncated Deguelin Derivatives Against A549, HCT116, and MCF-7 Cancer Cells

Deguelin has been extensively studied for its anticancer properties; however, its clinical application has been hindered by concerns about in vivo toxicity. Structural modifications of deguelin including ring truncation have been explored to enhance its pharmacological properties. In this study, the design and straightforward synthesis of a series of B, C, and E (BCE)-ring-truncated deguelin analogues with deoxybenzoin backbone were described. The structure-activity relationships (SARs) were established by evaluation of their inhibitory activities against three cancer cell lines, A549 (adenocarcinomic human alveolar basal epithelial cells), HCT116 (human colorectal cancer cells), and MCF-7 (breast cancer cells). Six derivatives demonstrated significant and selective inhibitory activities. The ketone derivative 3a showed potency against A549 (IC50 = 6.62 μM) while the oxime analogue 6a and D-ring-benzylated ketone analogue 8d exhibited activity against HCT116 (IC50 = 3.43 and 6.96 μM, respectively). Moreover, the D-ring alkylated derivatives 8c and 8e-f were active against MCF-7 cells (IC50 < 10 μM). The potential suitability of the BCE-ring-truncated deguelin derivatives for drug development was further supported by the favorable in silico prediction of their physicochemical properties, druglikeness, and toxicity. This study could provide valuable insights for the further development of novel anticancer agents.

Pharmacological basis and new insights of deguelin concerning its anticancer effects

Deguelin is a rotenoid of the flavonoid family, which can be extracted from Lonchocarpus, Derris, or Tephrosia. It possesses the inhibition of cancer cell proliferation by inducing apoptosis through regulating the phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) signaling pathway, the NF-κB signaling pathway, the Wnt signaling pathway, the adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) signaling pathway and epidermal growth factor receptor (EGFR) signaling, activating the p38 mitogen-activated protein kinase (MAPK) pathway, repression of Bmi1, targeting cyclooxygenase-2 (COX-2), targeting galectin-1, promotion of glycogen synthase kinase-3β (GSK3β)/FBW7-mediated Mcl-1 destabilization and targeting mitochondria via down-regulating Hexokinases II-mediated glycolysis, PUMA-mediation, which are some crucial molecules which modulate closely cancer cell growth and metastasis. Deguelin inhibits tumor cell propagation and malignant transformation through targeting angiogenesis, targeting lymphangiogenesis, targeting focal adhesion kinase (FAK), inhibiting the CtsZ/FAK signaling pathway, targeting epithelial-mesenchymal transition (EMT), the NF-κB signaling pathway, regulating NIMA-related kinase 2 (NEK2). In addition, deguelin possesses other biological activities, such as targeting cell cycle arrest, modulation of autophagy, inhibition of hedgehog pathway, inducing differentiation of mutated NPM1 acute myeloid leukemia etc. Therefore, deguelin is a promising chemopreventive agent for cancer therapy.

Assessment of Unstimulated Whole Salivary Tumor Necrosis Factor Alpha (TNF-α) and Cellular Micronuclei Levels in Snuff (Naswar) Users and Non-Users for Early Diagnosis of Oral Squamous Cell Carcinoma

The aim of the study was to investigate the unstimulated whole saliva (UWS) tumor necrosis factor alpha (TNF-α) and cellular micronuclei in snuff dippers (Naswar) compared to healthy control subjects. The case control study was conducted over 9 months at a tertiary care center. Sixty patients were divided into two groups: Snuff dippers (SD) (Naswar) and non-snuff dippers (NSD) (control subjects). The included self-reported SD used Snuff twice daily for more than 12 months. UWS was collected and salivary TNF-α assessment was performed using enzyme-linked immunosorbent assay (ELISA). For cellular micronuclei, buccal mucosa was brushed to obtain cells in Naswar users, fixed with a dibutylphthalate polystyrene xylene (DPX) mounting to view micronuclei. Means and standard deviations were compared using the t-test and outcomes were related using Pearson correlation, considering p ≤ 0.05 as significant. The mean age of participants was 38.85 ± 11.56 years. The mean duration of snuff use was 20.43 ± 12.79 years and the common site for Naswar placement was the lower vestibule (n = 19, 63.3%). TNF-α levels among SD were 9.6 ± 3.3 pg/mL, which were significantly higher than levels in NSD, 5.2 ± 3 pg/mL (p < 0.05). The number of cellular micronuclei in SD was 30.7 ± 7.8, which was comparatively higher than in NSD, which was 9.2 ± 3.3 (p < 0.05). The duration of snuff use was positively correlated to TNF-α levels (p = 0.048) rather than the micronuclei number (p = 0.97). SD showed higher levels of TNF-α and cellular micronuclei compared with NSD (control subjects); a positive correlation was shown with the duration of snuff use. We conclude that TNF-α and micronuclei are potential salivary biomarkers for an oral biological effect in snuff (Naswar) users.

Deguelin targets multiple oncogenic signaling pathways to combat human malignancies

Cancer is an anomalous growth and differentiation of cells known to be governed by oncogenic factors. Plant-based natural metabolites have been well recognized to possess chemopreventive properties. Deguelin, a natural rotenoid, is among the class of bioactive phytoconstituents from a diverse range of plants with potential antineoplastic effects in different cancer subtypes. However, the precise mechanisms of how deguelin inhibits tumor progression remains elusive. Deguelin has shown promising results in targeting the hallmarks of tumor progression via inducing tumor apoptosis, cell cycle arrest, and inhibition of angiogenesis and metastasis. Based on initial scientific excerpts, deguelin has been reported to inhibit tumor growth via different signaling pathways, including mitogen-activated protein kinase, phosphoinositide 3-kinase, serine/threonine protein kinase B (also known as Akt), mammalian target of rapamycin, nuclear factor-κB, matrix metalloproteinase (MMP)-2, MMP-9 and caspase-3, caspase-8, and caspase-9. This review summarizes the mechanistic insights of antineoplastic action of deguelin to gain a clear understanding of its therapeutic effects in cancer. The anticancer potential of deguelin with respect to its efficacy in targeting tumorigenesis via nanotechnological approaches is also investigated. The initial scientific findings have presented deguelin as a promising antitumorigenic agent which can be used for monotherapy as well as synergistically to augment efficacy of chemotherapeutic treatment regimes.

Rotenone restrains colon cancer cell viability, motility and epithelial‑mesenchymal transition and tumorigenesis in nude mice via the PI3K/AKT pathway

Rotenone, a natural hydrophobic pesticide, has been reported to display anticancer activity in a variety of cancer cells. However, the mechanism of rotenone on colon cancer (CC) cell migration, invasion and metastasis is still unknown. In the present study, the cytotoxicity of rotenone on CC cells were detected by the Cell Counting Kit‑8 assay and confirmed by clone formation assay. The effects of rotenone on CC cell invasion and migration activity were determined in vitro by Transwell invasion and wound healing assays, respectively. In addition, to reveal whether rotenone affected the epithelial‑mesenchymal‑transition (EMT) process, reverse transcription‑quantitative PCR, western blotting and immunofluorescence assays were used to detect the expression of EMT markers. The expression levels of the key markers of the PI3K/AKT pathway after rotenone treatment alone or in combination with a PI3K/AKT signaling activator in CC were also detected by western blotting. Finally, the in vivo antitumor effects of rotenone were evaluated in a subcutaneous xenotransplant tumor model treated with an intraperitoneal injection of rotenone. The results of the present study demonstrated that rotenone treatment induced CC cell cytotoxicity and greater effects were observed with increasing concentrations and inhibited cell proliferation compared with untreated cells. In vitro cell function assays revealed that rotenone inhibited CC cell migration, invasion and EMT compared with untreated cells. Mechanically, the phosphorylation levels of AKT and mTOR were downregulated in rotenone‑treated CC cells compared with untreated cells. Additionally, AKT and mTOR phosphorylation levels were increased by the PI3K/AKT signaling activator insulin‑like growth factor 1 (IGF‑1), which was reversed by rotenone treatment. The cell function assays confirmed that the IGF‑1‑activated cell proliferation, migration and invasion were decreased by rotenone treatment. These results indicated that rotenone affected CC cell proliferation and metastatic capabilities by inhibiting the PI3K/AKT/mTOR signaling pathway. In addition, rotenone inhibited tumor growth and metastatic capability of CC, which was confirmed in a xenograft mouse model. In conclusion, the present study revealed that rotenone inhibited CC cell viability, motility, EMT and metastasis in vitro and in vivo by inhibiting the PI3K/AKT/mTOR signaling pathway.

Dihydroartemisinin Prevents Progression and Metastasis of Head and Neck Squamous Cell Carcinoma by Inhibiting Polarization of Macrophages in Tumor Microenvironment

Background

Polarized M2 macrophages are an important type of tumor-associated macrophage (TAM), with roles in the growth, invasion, and migration of cancer cells in the tumor microenvironment. Dihydroartemisinin (DHA), a traditional Chinese medicine extract, has been shown to inhibit the progression and metastasis of head and neck squamous cell carcinoma (HNSCC); however, the effect of DHA on cancer prevention, and the associated mechanism, has not been investigated in the tumor microenvironment.

Materials and Methods

First, human Thp-1 monocytes were induced and differentiated into M2 macrophages using phorbol 12-myristate 13-acetate (PMA), interleukin-6 (IL-6), and interleukin-4 (IL-4). Induction success was confirmed by cell morphology evaluation, flow cytometry, and quantitative real-time polymerase chain reaction (qRT-PCR). Then, DHA was applied to interfere with M2 macrophage polarization, and conditioned medium (CM), including conditioned medium from M2 macrophages (M2-CM) and conditioned medium from M2 macrophages with DHA (M2-DHA-CM), was obtained. CM was applied to Fadu or Cal-27 cells, and its effects on cancer invasion, migration, and angiogenesis were evaluated using transwell, wound-healing, and tube formation assays, respectively. Finally, Western blotting was used to evaluate the relationship between signal transducer and activator of transcription 3 (STAT3) signaling pathway activation and M2 macrophage polarization.

Results

Human Thp-1 monocytes were successfully polarized into M2-like TAMs using PMA, IL-6, and IL-4. We found that M2-like TAMs promoted the invasion, migration, and angiogenesis of HNSCC cells; however, DHA significantly inhibited IL-4/IL-6-induced M2 macrophage polarization. Additionally, as DHA induced a decrease in the number of M2-like TAMs, M2-DHA-CM inhibited the induction of invasion, migration, and angiogenesis of Fadu and Cal-27 cells. Finally, DHA inhibited M2 macrophage polarization by blocking STAT3 pathway activation in macrophages.

Conclusion

DHA inhibits the invasion, migration, and angiogenesis of HNSCC by preventing M2 macrophage polarization via blocking STAT3 phosphorylation.

Progress in Drug and Formulation Development for the Chemoprevention of Oral Squamous Cell Carcinoma: A Review

BACKGROUND

Cancer is a life-threatening global problem with high incidence rates. Prioritizing the prevention of cancer, chemopreventive agents have drawn much attention from the researchers.

OBJECTIVE

This review focuses on the discussion of the progress in the development of chemopreventive agents and formulations related to the prevention of oral cancer.

METHODS

In this perspective, an extensive literature survey was carried out to understand the mechanism, control and chemoprevention of oral cancer. Different patented agents and formulations have also exhibited cancer preventive efficacy in experimental studies. This review summarizes the etiology of oral cancer and developments in prevention strategies.

RESULTS

The growth of oral cancer is a multistep activity necessitating the accumulation of genetic as well as epigenetic alterations in key regulatory genes. Many risk factors are associated with oral cancer. Genomic technique for sequencing all tumor specimens has been made available to help detect mutations. The recent development of molecular pathway and genetic tools has made the process of diagnosis easier, better forecast and efficient therapeutic management. Different chemical agents have been studied for their efficacy to prevent oral cancer and some of them have shown promising results.

CONCLUSION

Use of chemopreventive agents, either synthetic or natural origin, to prevent carcinogenesis is a worthy concept in the management of cancers. Preventive measures are helpful in controlling the occurrence or severity of the disease. The demonstrated results of preventive agents have opened an arena for the development of promising chemopreventive agents in the management of oral squamous cell carcinoma.

Effects of flavonoids on tongue squamous cell carcinoma

Squamous cell carcinoma (SCC) of the tongue is associated with tobacco use, alcohol abuse, and human papillomavirus (HPV) infections. While clinical outcomes have recently improved for HPV-positive patients in general, 50% of patients suffering from tongue cancer die within 5 years of being diagnosed. Flavonoids are secondary plant metabolites with a wide range of biological activities including antioxidant, anti-inflammatory, and anticancer activities. Flavonoids have generated high interest as therapeutic agents owing to their low toxicity and their effects on a large variety of cancer cell types. In this literature review, we evaluate the actions of flavonoids on SCC of the tongue demonstrated in both in vivo and in vitro models.

Akt inhibitor deguelin aggravates inflammation and fibrosis in myocarditis

OBJECTIVES

Myocarditis is characterized by inflammatory cell infiltration in myocardial stroma. Attenuation of tumor necrosis factor (TNF)-α and interleukin (IL)-1β is a reliable mark for improving the prognosis. Protein kinase B (Akt) plays an important role in the development and progression of myocarditis. The specific role of the natural inhibitor of Akt, Deguelin, on myocarditis has not been reported. In this study, we used deguelin to investigate the effects of natural Akt inhibitor on myocarditis in experimental autoimmune myocarditis (EAM) rats.

MATERIALS AND METHODS

EAM rat models were made by using Lewis rats and Deguelin was injected intraperitoneally on day 3, 6, 9, 12 and 15 after successful modeling. On day 18, rats were sacrificed and the heart weight (HW)/ body weight (BW) ratio were measured. The pathological changes, pathological scores and fibrosis area were evaluated after H.&E. and Masson's trichrome staining. The mRNA levels of TNF-α and IL-1β were measured by RT-qPCR, while the protein expressions of TNF-α and IL-1β were detected by immunohistochemical staining and Western bolt. The protein expressions of Akt, Akt1, phosphorylated (p-) Akt and nuclear factor (NF)-κB were detected by Western bolt.

RESULTS

We found that the TNF-α and IL-1β levels, inflammatory scores and fibrosis areas were markedly increased after 18 days deguelin administration.

CONCLUSION

Akt inhibition with deguelin may aggravate myocarditis of EAM rats.

HSPD1 repressed E-cadherin expression to promote cell invasion and migration for poor prognosis in oral squamous cell carcinoma

Buccal mucosa squamous cell carcinoma (BMSCC) is one of major subsites of oral cancer and is associated with a high rate of metastasis and poor prognosis. Heat shock proteins (HSPs) act as potential prognostic biomarkers in many cancer types. However, the role of HSPD1 in oral cancer, especially in BMSCC, is still unknown. Through data analysis with The Cancer Genome Atlas (TCGA), we found the association of HSPD1 gene expression with tumorigenesis and poor prognosis in oral cancer patients. Our cohort study showed that higher HSPD1 protein level was associated with tumorigenesis and poor prognosis in BMSCC patients with lymph node invasion, suggesting that HSPD1 may be involved in tumor metastasis. Moreover, knockdown of HSPD1 induced E-cadherin expression and decreased the migration and invasion of BMSCC cells. In contrast, ectopic expression of HSPD1 diminished E-cadherin expression and promoted the migration/invasion of BMSCC cells. Further, HSPD1 regulated RelA activation to repress E-cadherin expression, enhancing the migration and invasion of BMSCC cells. Furthermore, HSPD1 protein level was inversely correlated with E-cadherin protein level in tumor tissues and co-expression of high HSPD1/low E-cadherin showed a significant association with poor prognosis in BMSCC patients. Taken together, HSPD1 might repress E-cadherin expression and promote metastatic characters of BMSCC cells for poor prognosis of BMSCC patients.

Biopharmacological considerations for accelerating drug development of deguelin, a rotenoid with potent chemotherapeutic and chemopreventive potential

Deguelin is a rotenoid compound that exists in abundant quantities in the bark, roots, and leaves of the Leguminosae family of plants. An analysis of evidence from both in vitro and in vivo studies suggests that deguelin displays potent anticancer activity against multiple cancer types and exhibits chemopreventive potential in Akt-inducible transgenic mouse models. Deguelin appears to impede carcinogenesis by enhancing cell apoptosis and hindering malignant transformation and tumor cell propagation. Crucial oncogenic pathways likely targeted by deguelin include the epithelial-to-mesenchymal transition; angiogenesis-related pathways; and the phosphoinositide 3-kinase/Akt, Wnt, epidermal growth factor receptor, c-Met, and hedgehog signal transduction cascades. This review article provides a comprehensive summary of current preclinical research featuring deguelin as a leading chemotherapeutic and chemopreventive compound, and it highlights the importance of identifying companion molecular biomarkers and performing systemic pharmacokinetic studies for accelerating the process of developing deguelin as a clinical anticancer agent.

Deguelin attenuates non-small cell lung cancer cell metastasis through inhibiting the CtsZ/FAK signaling pathway

Lung cancer is the leading cause of cancer-related death among both men and women every year, mainly due to metastasis. Although natural compound deguelin has been reported to inhibited cell migration and invasion in various cancer cells, the details of this regulation progress remain to be fully elucidated. In this study, we investigated the underlying mechanism of deguelin-suppressed metastasis of non-small cell lung cancer (NSCLC) cells. Our results demonstrate that deguelin inhibits NSCLC cell migration, invasion, and metastasis both in vitro and in vivo. These inhibitory effects of deguelin were mediated by suppressing of Cathepsin Z (CtsZ) expression and interrupting the interaction of CtsZ with integrin β3. Moreover, deguelin inhibits the activation of CtsZ downstream FAK/Src/Paxillin signaling. Knockdown of CtsZ mimicked the effect of deguelin on NSCLC cells migration and invasion. Our study reveals that deguelin exerts its anti-metastatic effect both in vitro and in vivo is partly dependent on the suppression of CtsZ signaling. Deguelin would be a potential anti-metastasis agent against NSCLC.

Deguelin Impairs Cell Adhesion, Migration and Invasion of Human Lung Cancer Cells through the NF-[Formula: see text]B Signaling Pathways

Deguelin, a rotenoid, is isolated from a natural plant species, and has biological activities including antitumor function. In the present study, we investigated the effect of deguelin on the cell adhesion, migration and invasion of NCI-H292 human lung cancer cells in vitro. Cell viability was analyzed by using flow cytometer. Cell adhesion was determined by using the cell-matrix adhesion assay. Wound healing assay was used to examine cell migration. Cell migration and invasion were investigated using a Boyden chamber assay. The protein expression was measured by Western blotting and confocal laser microscopy. The electrophoretic mobility shift assay was used to measure NF-[Formula: see text]B p65 binding to DNA.We selected the concentrations of deguelin at 0, 0.5, 1.0, 1.5, 2.0 and 2.5[Formula: see text][Formula: see text]M and we found that those concentrations of deguelin did not induce significant cytotoxic effects on NCI-H292 cells. Thus, we selected those concentrations of deguelin for metastasis assay. We found that deguelin inhibited cell adhesion, migration and invasion in dose-dependent manners that was assayed by wound healing and transwell methods, respectively. Deguelin decreased the expression of MMP-2/-9, SOS 1, Rho A, p-AKT (Thr308), p-ERK1/2, p-p38, p-JNK, NF-[Formula: see text]B (p65) and uPA in NCI-H292 cells. Deguelin suppressed the expression of PI3K, SOS 1, NF-[Formula: see text]B (p65), but did not significantly affect PKC and Ras in the nuclei of NCI-H292 cells that were confirmed by confocal laser microscopy. We suggest that deguelin may be used as a novel anticancer metastasis of lung cancer in the future.

Deguelin exerts anticancer activity of human gastric cancer MGC-803 and MKN-45 cells in vitro

During the pathogenesis of gastric cancer, Akt signaling is considered as a pivotal inducer of gastric cancer development. Here we report the identification of anticancer activities of deguelin, a natural agent that inhibits Akt signaling. When applied to MGC-803 and MKN-45 cells, deguelin suppressed the proliferation and arrested cell cycle by p21-mediated inhibition of cyclin E. We further present in vitro evidence that deguelin promoted apoptosis of cancer cells by decreasing the phospho-Akt signaling and affecting expression of the apoptosis-associated genes Bax and Bcl-2. Additionally, deguelin was found to suppress the migration and invasion of gastric cancer cells. Taken together, these results indicated that deguelin exerted anticancer activity of human gastric cancer MGC-803 and MKN-45 cells in vitro.

Deguelin inhibits epithelial-to-mesenchymal transition and metastasis of human non-small cell lung cancer cells by regulating NIMA-related kinase 2

Background

Non‐small cell lung cancer is a lethal malignancy with a high mortality rate. Deguelin displays an anti‐tumor effect and inhibits metastasis in various cancers. The aberrant expression of NIMA‐related kinase 2 (NEK2) indicates poor prognosis and induces epithelial‐to‐mesenchymal transition (EMT) and metastasis processes. However, the underlying mechanism between deguelin and NEK2 has remained elusive.

Methods

NSCLC cell lines were treated with deguelin. Wound‐healing and invasion assays were applied to study the inhibitory effect of deguelin on NSCLC cells. EMT markers, E‐cadherin and Vimentin, were also detected by Western blot. NEK2 protein and messenger RNA expression levels were evaluated when NSCLC cells were treated with different concentrations of deguelin. The effect of NEK2 on NSCLC cell metastasis was evaluated through NEK2 knockdown. To investigate whether deguelin induced EMT by regulating NEK2, we overexpressed NEK2 in both NCI‐H520 and SK‐MES‐1 cell lines, and then used real time‐PCR to study the E‐cadherin and Vimentin messenger RNA expression in both NSCLC cells.

Results

Deguelin inhibited migration and invasion processes in NSCLC cell lines and decreased NEK2 expression in a concentration‐dependent manner. Furthermore, NEK2 knockdown inhibited NSCLC cell migration and invasion. Finally, overexpressing NEK2 in NCI‐H520 and SK‐MES‐1 cells could restore the inhibition of metastasis induced by deguelin.

Conclusions

Deguelin could inhibit EMT and metastasis, while overexpression of NEK2 promotes these processes. Deguelin could decrease NEK2 expression, while NEK2 overexpression could restore deguelin‐induced inhibition of metastasis.

Deguelin Attenuates Allergic Airway Inflammation via Inhibition of NF-κb Pathway in Mice

Asthma is a chronic respiratory disease characterized by airway inflammation and remodeling, resulting in a substantial economic burden on both patients and society. Deguelin, a constituent of the Leguminosae family, exhibits anti-proliferative and anti-inflammatory activities in cancer mice models via inhibiting phosphatidylinositol 3-kinases and the NF-κB pathway. We demonstrated that deguelin effectively reduced OVA-induced inflammatory cell recruitment, decreased lung tissue inflammation and mucus production, suppressed airway hyperresponsiveness, and inhibited serum immunoglobulin and Th2 cytokine levels in a dose-dependent manner in asthmatic mice. In addition, we found that deguelin reduced inflammatory gene expressions both in vivo and in vitro, which were closely associated with activation of the NF-κB signaling pathway. Thus, we further explored the underlying mechanisms of deguelin in normal human bronchial epithelial cells (BEAS-2B). Our results suggested that deguelin inhibited NF-κB binding activity by enhancing the ability of IκBα to maintain NF-κB in an inactive form in the cytoplasm and preventing the TNF-α induced translocation of p65 to the nucleus. In conclusion, our research indicates that deguelin attenuates allergic airway inflammation via inhibition of NF-κB pathway in mice model and may act as a potential therapeutic agent for patients with allergic airway inflammation.

Hepatitis C Virus Nonstructural 5A Protein (HCV-NS5A) Inhibits Hepatocyte Apoptosis through the NF-κb/miR-503/bcl-2 Pathway

The nonstructural protein 5A (NS5A) encoded by the human hepatitis C virus (HCV) RNA genome is a multifunctional phosphoprotein. To analyse the influence of NS5A on apoptosis, we established an Hep-NS5A cell line (HepG2 cells that stably express NS5A) and induced apoptosis using tumour necrosis factor (TNF)-α. We utilised the MTT assay to detect cell viability, real-time quantitative polymerase chain reaction and Western blot to analyse gene and protein expression, and a luciferase reporter gene experiment to investigate the targeted regulatory relationship. Chromatin immunoprecipitation was used to identify the combination of NF-κB and miR-503. We found that overexpression of NS5A inhibited TNF-αinduced hepatocellular apoptosis via regulating miR-503 expression. The cell viability of the TNF-α induced Hep-mock cells was significantly less than the viability of the TNF-α induced Hep-NS5A cells, which demonstrates that NS5A inhibited TNF-α-induced HepG2 cell apoptosis. Under TNF-α treatment, miR-503 expression was decreased and cell viability and B-cell lymphoma 2 (bcl-2) expression were increased in the Hep-NS5A cells. Moreover, the luciferase reporter gene experiment verified that bcl-2 was a direct target of miR-503, NS5A inhibited TNF-α-induced NF-κB activation and NF-κB regulated miR-503 transcription by combining with the miR-503 promoter. After the Hep-NS5A cells were transfected with miR-503 mimics, the data indicated that the mimics could reverse TNF-α-induced cell apoptosis and blc-2 expression. Collectively, our findings suggest a possible molecular mechanism that may contribute to HCV treatment in which NS5A inhibits NF-κB activation to decrease miR-503 expression and increase bcl-2 expression, which leads to a decrease in hepatocellular apoptosis.

Deguelin Potentiates Apoptotic Activity of an EGFR Tyrosine Kinase Inhibitor (AG1478) in PIK3CA-Mutated Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinoma (HNSCC) is known to be intrinsically resistant to inhibitors for epidermal growth factor receptor (EGFR). Until now, clinical outcomes for HNSCC using EGFR inhibitors as single agents have yielded disappointing results. Here, we aimed to study whether combinatorial treatment using AG1478 (EGFR tyrosine kinase inhibitor) and deguelin, which is a rotenoid isolated from the African plant Mundulea sericea, could enhance the anti-tumor effects of AG1478 in HNSCC. For Ca9-22 cells with EGFR, KRAS, and PIK3CA wild types, AG1478 alone suppressed both phosphorylated levels of ERK and AKT and induced apoptosis. On the contrary, for HSC-4 cells with EGFR and KRAS wild types, and a PIK3CA mutant, AG1478 alone did not suppress the phosphorylated level of AKT nor induce apoptosis, while it suppressed ERK phosphorylation. Forced expression of constitutively active PIK3CA (G1633A mutation) significantly reduced the apoptotic effect of AG1478 on the PIK3CA wild-type Ca9-22 cells. When HSC-4 cells with the PIK3CA G1633A mutation were treated with a combination of AG1478 and deguelin, combination effects on apoptosis induction were observed through the inhibition of the AKT pathway. These results suggest that the combination of EGFR tyrosine kinase inhibitor with deguelin is a potential therapeutic approach to treat PIK3CA-mutated HNSCC.

Deguelin Induces the Apoptosis of Lung Squamous Cell Carcinoma Cells through Regulating the Expression of Galectin-1

Lung cancer is the leading cause of cancer mortality around the world. Despite advances in the targeted therapy, patients with lung squamous cell carcinoma(SCC) still benefit few from it, and the search for potential effective therapies is imperative. Here, we demonstrated that deguelin induced significant apoptosis of lung SCC cells in vitro. Importantly, we found deguelin down-regulated the expression of galectin-1, which was involved in a wide range of tumorous physiologic process. Thus, we both over-expressed and down-regulated galectin-1 to perform its role in deguelin-induced apoptosis. We found that increased galectin-1 attenuated apoptosis of SCC cells exposed to deguelin, while galectin-1 knockdown sensitized lung cancer cells to deguelin treatment. Additionally, we observed that down-regulation of galectin-1 resulted in suppression of Ras/Raf/ERK pathway which was involved in deguelin-induced cell apoptosis. We also found that deguelin had a significant anti-tumor ability with decline of galectin-1 in vivo. In conclusion, these findings confirm that deguelin may act as a new chemo-preventive agent through inducing apoptosis of lung SCC cells in a galectin-1 dependent manner.

Potential Compounds for Oral Cancer Treatment: Resveratrol, Nimbolide, Lovastatin, Bortezomib, Vorinostat, Berberine, Pterostilbene, Deguelin, Andrographolide, and Colchicine

Oral cancer is one of the main causes of cancer-related deaths in South-Asian countries. There are very limited treatment options available for oral cancer. Research endeavors focused on discovery and development of novel therapies for oral cancer, is necessary to control the ever rising oral cancer related mortalities. We mined the large pool of compounds from the publicly available compound databases, to identify potential therapeutic compounds for oral cancer. Over 84 million compounds were screened for the possible anti-cancer activity by custom build SVM classifier. The molecular targets of the predicted anti-cancer compounds were mined from reliable sources like experimental bioassays studies associated with the compound, and from protein-compound interaction databases. Therapeutic compounds from DrugBank, and a list of natural anti-cancer compounds derived from literature mining of published studies, were used for building partial least squares regression model. The regression model thus built, was used for the estimation of oral cancer specific weights based on the molecular targets. These weights were used to compute scores for screening the predicted anti-cancer compounds for their potential to treat oral cancer. The list of potential compounds was annotated with corresponding physicochemical properties, cancer specific bioactivity evidences, and literature evidences. In all, 288 compounds with the potential to treat oral cancer were identified in the current study. The majority of the compounds in this list are natural products, which are well-tolerated and have minimal side-effects compared to the synthetic counterparts. Some of the potential therapeutic compounds identified in the current study are resveratrol, nimbolide, lovastatin, bortezomib, vorinostat, berberine, pterostilbene, deguelin, andrographolide, and colchicine.