Nobiletin Down-Regulates c-KIT Gene Expression and Exerts Antileukemic Effects on Human Acute Myeloid Leukemia Cells

Hesperidin facilitating gastrointestinal motility by "Gut-brain axis" and "SCF/C-Kit signaling pathways"

Hesperidin shows promising results as a potential feed additive for enhancing gastrointestinal motility in animals. Gastrointestinal function plays a pivotal role in animal growth and the digestibility of dietary nutrients, with gastrointestinal motor function serving as a crucial component. However, limited research has been conducted on the application of hesperidin as a feed additive to promote gastrointestinal motility. The present study aims to assess the efficacy of Hesperidin as a feed additive in promoting gastrointestinal motility and elucidating its underlying mechanism. A total of 200 newly hatched (1-day-old) broilers with similar body weight were randomly allocated into 4 groups as follows: the control group receiving only the basal diet, and the other 3 groups supplemented with 50, 100, and 150 mg of hesperidin per kg of the basal diet, respectively. Each group consisted of 5 replicates with ten broilers per replicate, and the feeding trial lasted for a duration of 21 d. At 21 d of age, a 5% w/v Evans Blue solution in distilled water was utilized to measure intestinal transit rates (ITR). Gastric emptying (GE) was evaluated by administering a phenol red solution at a concentration of 0.05% w/v (1 mL/broiler). Fifteen broilers from each group were euthanized and immediately dissected to obtain gizzard, hypothalamus, duodenum, and jugular blood samples. Jugular blood samples were collected for brain-gut peptide content analysis, while gizzard, hypothalamus, and duodenum samples were used for immunohistochemical analysis. Real-time qPCR was performed on gizzard samples. The results demonstrated a significant improvement in the GE and ITR of broilers in all treatment groups compared to the control group (P < 0.05), particularly in the 100mg/Kg and 150mg/Kg hesperidin group. Incorporation of hesperidin into the broilers' diet significantly enhances serum levels of ghrelin, encompassing serotonin (5-HT), motilin (MTL), cholecystokinin (CCK), and Stem Cell Factor (SCF) as well as substance P (SP) in the gizzard and duodenal tissues while reducing vasoactive intestinal peptide (VIP) levels (P < 0.05). The group administered a dosage of 150mg/Kg exhibited the most pronounced effect.Immunohistochemistry analysis revealed that hesperidin supplementation up-regulated SP protein content and down-regulated VIP protein content in the hypothalamus, gizzard, and duodenum of broilers (P < 0.05), with the most pronounced effect illustrated in the 150mg/Kg hesperidin group. Furthermore, addition of hesperidin to broiler feed resulted in a significant up-regulation of protein expression and gene expression related to SCF and The protein expression of Receptor tyrosine kinase (C-Kit) was significantly upregulated in the 150mg/Kg group, while the gene expression of C-Kit was significantly upregulated in the 50 mg/Kg group (P < 0.05). In conclusion, hesperidin exhibits promising potential as a feed additive for broilers, as its dietary supplementation of hesperidin improves gastrointestinal motility through modulation of both "gut-brain axis" signaling pathways and "SCF/C-Kit signaling pathways" within broiler chicken's digestive system. Notably, basal diet supplemented with 150mg/Kg hesperidin demonstrates superior efficacy.

The pro-differentiating capability of a flavonoid-rich extract of Citrus bergamia juice prompts autophagic death in THP-1 cells

Acute myeloid leukemia (AML) is a hematologic neoplasm, characterized by a blockage of differentiation and an unconstrained proliferation of immature myeloid cells. Recently, the survival of leukemia patients has increased thanks to the use of differentiating agents, though these may cause serious side effects. Hence, the search for safer differentiating compounds is necessary. Our aim was to assess the pro-differentiating effects of a flavonoid-rich extract of bergamot juice (BJe) in human monocytic leukemia THP-1 cells, an in vitro AML model. For the first time, we showed that treatment with BJe induced differentiation of THP-1 cells, changes in cell morphology and increased expression of differentiation-associated surface antigens CD68, CD11b and CD14. Moreover, BJe enhanced protein levels of autophagy-associated markers, such as Beclin-1 and LC3, as well as induced the phosphorylation of the MAPKs JNK, ERK and p38, hence suggesting a potential mechanism underlying its antiproliferative effects. Indeed, parallel experiments highlighted that BJe was able to hamper THP-1 cell growth. In conclusion, our study suggests that BJe induces the differentiation of THP-1 cells and reduces their proliferation, highlighting its potential in differentiation therapy of AML.

Naringenin Promotes Gastrointestinal Motility in Mice by Impacting the SCF/c-Kit Pathway and Gut Microbiota

Naringenin (NRG) is widely found in citrus fruits and has anti-inflammatory, hypoglycemic, and immunomodulatory effects. Previous studies have shown that NRG promotes gastrointestinal motility in mice constipation models, but there are few systematic evaluations of its effects on normal animals. This study first clarified the promotive effects of NRG on gastric emptying and small intestine propulsion (p < 0.01). NRG can also regulate the release of gastrointestinal hormones, including enhancing gastrin (GAS) and motilin (MTL) (p < 0.01), while reducing vasoactive intestinal peptide (VIP) secretion (p < 0.01). Using NRG to stimulate the isolated stomach, duodenum, and colon showed similar promotive effects to those observed in vivo (p < 0.01). A Western blot analysis indicated that this effect may be mediated by increasing the expression of stem cell factor (SCF) and its receptor (c-Kit) in these three segments, thus regulating their downstream pathways. It is worth noting that NRG can also increase the proportion of beneficial bacteria (Planococcaceae, Bacteroides acidifaciens, Clostridia_UCG-014) in the intestine and reduce the quantity of harmful bacteria (Staphylococcus). These findings provide a new basis for the application of NRG.

Investigation of Molecular Mechanisms of S-1, Docetaxel and Cisplatin in Gastric Cancer with a History of Helicobacter Pylori Infection

Gastric cancer rates and fatality rates have not decreased. Gastric cancer treatment has historically included surgery (both endoscopic and open), chemotherapy, targeted therapy, and immunotherapy. One of the aggravating carriers of this cancer is Helicobacter pylori infection. Various drug combinations are used to treat gastric cancer. However, examining the molecular function of these drugs, depending on whether or not there is a history of Helicobacter pylori infection, can be a better help in the treatment of these patients. This study was designed as bioinformatics. Various datasets such as patients with gastric cancer, with and without a history of H. pylori, and chemotherapy drugs cisplatin, docetaxel, and S-1 were selected. Using Venn diagrams, the similarities between gene expression profiles were assessed and isolated. Then, selected the signal pathways, ontology of candidate genes and proteins. Then, in clinical databases, we confirmed the candidate genes and proteins. The association between gastric cancer patients with and without a history of H. pylori with chemotherapy drugs was investigated. The pathways of cellular aging, apoptosis, MAPK, and TGFβ were clearly seen. After a closer look at the ontology of genes and the relationship between proteins, we nominated important biomolecules. Accordingly, NCOR1, KIT, MITF, ESF1, ARNT2, TCF7L2, and KRR1 proteins showed an important role in these connections. Finally, NCOR1, KIT, KRR1, and ESF1 proteins showed a more prominent role in the molecular mechanisms of S-1, Docetaxel, and Cisplatin in gastric cancer associated with or without H. pylori.

Pinostrobin modulates FOXO3 expression, nuclear localization, and exerts antileukemic effects in AML cells and zebrafish xenografts

Acute myeloid leukemia (AML) is a disease characterized by abnormal cell proliferation in the bone marrow and is the most common quickly progressive leukemia in adults. Pinostrobin, a flavonoid phytochemical, has been reported to exhibit antioxidant, anti-inflammatory, and anticancer properties. In this study, we aimed to investigate the antileukemic effects of pinostrobin and its molecular mechanisms in human AML cells. Our study found that pinostrobin (0-80 μM) significantly reduced the viability of human AML cells, with the pronounced cytotoxic effects observed in MV4-11 > MOLM-13 > HL-60 > U-937 > THP-1 cells. Pinostrobin was found to suppress leukemia cell proliferation, modulate cell cycle progression, promote cell apoptosis, and induce monocytic differentiation in MV4-11 cells. In animal studies, pinostrobin significantly suppressed the growth of leukemia cells in a zebrafish xenograft model. Microarray-based transcriptome analysis showed that the differentially expressed genes (DEGs) in pinostrobin-treated cells were strongly associated with enriched Gene Ontology (GO) terms related to apoptotic process, cell death, cell differentiation, cell cycle progression, and cell division. Combining DisGeNET and STRING database analysis revealed that pinostrobin upregulates forkhead box 3 (FOXO3), a tumor suppressor in cancer development, and plays an essential role in controlling AML cell viability. Our study demonstrated that pinostrobin increases FOXO3 gene expression and promotes its nuclear translocation, leading to the inhibition of cell growth. Finally, the study found that pinostrobin, when combined with cytarabine, synergistically reduces the viability of AML cells. Our current findings shed light on pinostrobin's mechanisms in inhibiting leukemia cell growth, highlighting its potential as a chemotherapeutic agent or nutraceutical supplement for AML prevention or treatment.

8-Hydroxydaidzein Induces Apoptosis and Inhibits AML-Associated Gene Expression in U-937 Cells: Potential Phytochemical for AML Treatment

BACKGROUND

8-hydroxydaidzein (8-OHD) is a compound derived from daidzein, known for its anti-inflammatory and anti-proliferative properties in K562 human chronic myeloid leukemia (CML) cells. However, its effects on acute myeloid leukemia (AML) cells have not been fully understood.

METHOD

To investigate its potential anti-AML mechanism, we employed an integrated in vitro-in silico approach.

RESULTS

Our findings demonstrate that 8-OHD suppresses the expression of CDK6 and CCND2 proteins and induces cell apoptosis in U-937 cells by activating Caspase-7 and cleaving PARP-1. Microarray analysis revealed that 8-OHD downregulates differentially expressed genes (DEGs) associated with rRNA processing and ribosome biogenesis pathways. Moreover, AML-target genes, including CCND2, MYC, NPM1, FLT3, and TERT, were downregulated by 8-OHD. Additionally, molecular docking software predicted that 8-OHD has the potential to interact with CDK6, FLT3, and TERT proteins, thereby reducing their activity and inhibiting cell proliferation. Notably, we discovered a synergic pharmacological interaction between 8-OHD and cytarabine (Ara-C).

CONCLUSIONS

Overall, this study provides insights into the therapeutic applications of 8-OHD in treating AML and elucidates its underlying mechanisms of action.

Molecular landscape and clinical significance of exon 11 mutations in KIT gene among patients with gastrointestinal stromal tumor: a retrospective exploratory study

Objective

This aim of this study was to investigate the prognostic significance of KIT exon 11 mutation subtypes in patients with GISTs.

Methods

A total of 233 consecutive patients diagnosed with GISTs at the First Affiliated Hospital of Zhengzhou University from January 2013 to August 2018 were included in this study. The prevalence and mutation landscape of exon 11 in KIT was presented. The clinicopathological characteristics and prognosis among the different mutation subtypes were analyzed. All the statistical analyses were performed by SPSS22.0.

Results

Somatic mutational analysis indicated that point mutations were the most frequently detected mutations followed by deletions & compound mutations and insertion and tandem duplication mutations in the stomach. Point mutations showed a low mitotic count and a high risk of recurrence, and deletions and compound mutations have a high mitotic count while insertions and tandem duplication mutations showed a low mitotic count with an intermediate recurrence risk. Point mutations and deletions frequently occurred in sequence region codons 550-560 of exon 11, while compound mutations, insertion, and tandem duplication were mainly detected in codons 557-559, 572-580, and 577-581, respectively. The multi-variation analysis demonstrated that tumor diameter and high recurrence risk groups had worse prognostic values. However, mutation types were not significant predictors of relapse-free survival (RFS) in GISTs. Survival analysis suggested no significant difference in RFS between the 557/558 deletion and the other deletions.

Conclusion

This study suggested that mutations in exon 11 of the KIT gene were common with intermediate/high recurrence risk in GISTs patients. Tumor diameter ≥5 cm, and deletions mutations might predict a worse prognosis.

5-Demethylnobiletin mediates cell cycle arrest and apoptosis via the ERK1/2/AKT/STAT3 signaling pathways in glioblastoma cells

5-Demethylnobiletin is the active ingredient in citrus polymethoxyflavones that could inhibit the proliferation of several tumor cells. However, the anti-tumor effect of 5-Demethylnobiletin on glioblastoma and the underlying molecular mechanisms are remains unknown. In our study, 5-Demethylnobiletin markedly inhibited the viability, migration and invasion of glioblastoma U87-MG, A172 and U251 cells. Further research revealed that 5-Demethylnobiletin induces cell cycle arrest at the G0/G1 phase in glioblastoma cells by downregulating Cyclin D1 and CDK6 expression levels. Furthermore, 5-Demethylnobiletin significantly induced glioblastoma cells apoptosis by upregulating the protein levels of Bax and downregulating the protein level of Bcl-2, subsequently increasing the expression of cleaved caspase-3 and cleaved caspase-9. Mechanically, 5-Demethylnobiletin trigged G0/G1 phase arrest and apoptosis by inhibiting the ERK1/2, AKT and STAT3 signaling pathway. Furthermore, 5-Demethylnobiletin inhibition of U87-MG cell growth was reproducible in vivo model. Therefore, 5-Demethylnobiletin is a promising bioactive agent that might be used as glioblastoma treatment drug.

5-Demethylnobiletin Inhibits Cell Proliferation, Downregulates ID1 Expression, Modulates the NF-κB/TNF-α Pathway and Exerts Antileukemic Effects in AML Cells

Acute myeloid leukemia (AML) is characterized by the dysregulation of hematopoietic cell proliferation, resulting in the accumulation of immature myeloid cells in bone marrow. 5-Demethylnobiletin (5-demethyl NOB), a citrus 5-hydroxylated polymethoxyflavone, has been reported to exhibit various bioactivities, such as antioxidant, anti-inflammatory and anticancer properties. In this study, we investigated the antileukemic effects of 5-demethyl NOB and its underlying molecular mechanisms in human AML cells. We found that 5-demethyl NOB (20−80 μM) significantly reduced human leukemia cell viability, and the following trend of effectiveness was observed: THP-1 ≈ U-937 > HEL > HL-60 > K562 cells. 5-Demethyl NOB (20 and 40 μM) modulated the cell cycle through the regulation of p21, cyclin E1 and cyclin A1 expression and induced S phase arrest. 5-Demethyl NOB also promoted leukemia cell apoptosis and differentiation. Microarray-based transcriptome, Gene Ontology (GO) and Gene Set Enrichment Analysis (GSEA) of differentially expressed genes (DEGs) analysis showed that the expression of inhibitor of differentiation/DNA binding 1 (ID1), a gene associated with the GO biological process (BP) cell population proliferation (GO: 0008283), was most strongly suppressed by 5-demethyl NOB (40 μM) in THP-1 cells. We further demonstrated that 5-demethyl NOB-induced ID1 reduction was associated with the inhibition of leukemia cell growth. Moreover, DEGs involved in the hallmark gene set NF-κB/TNF-α signaling pathway were markedly enriched and downregulated by 5-demethyl NOB. Finally, we demonstrated that 5-demethyl NOB (20 and 40 μM), combined with cytarabine, synergistically reduced THP-1 and U-937 cell viability. Our current findings support that 5-demethyl NOB dramatically suppresses leukemia cell proliferation and may serve as a potential phytochemical for human AML chemotherapy.

Nobiletin as a chemopreventive natural product against cancer, a comprehensive review

As a leading cause of death, second only to heart disease, cancer has always been one of the burning topics in medical research. When targeting multiple signal pathways in tumorigenesis chemoprevention, using natural or synthetic anti-cancer drugs is a vital strategy to reduce cancer damage. However, toxic effects, multidrug resistance (MDR) as well as cancer stem cells (CSCs) all prominently limited the clinical application of conventional anticancer drugs. With low side effects, strong biological activity, unique mechanism, and wide range of targets, natural products derived from plants are considered significant sources for new drug development. Nobiletin is one of the most attractive compounds, a unique flavonoid primarily isolated from the peel of citrus fruits. Numerous studies in vitro and in vivo have suggested that nobiletin and its derivatives possess the eminent potential to become effective cancer chemoprevention agents through various cellular and molecular levels. This article aims to comprehensively review the anticancer efficacy and specific mechanisms of nobiletin, enhancing our understanding of its chemoprevention properties and providing the latest research findings. At the end of this review, we also give some discussion and future perspectives regarding the challenges and opportunities in nobiletin efficient exploitation.

8-Hydroxydaidzein Downregulates JAK/STAT, MMP, Oxidative Phosphorylation, and PI3K/AKT Pathways in K562 Cells

A metabolite isolated from fermented soybean, 8-hydroxydaidzein (8-OHD, 7,8,4′-trihydroxyisoflavone, NSC-678112), is widely used in ethnopharmacological research due to its anti-proliferative and anti-inflammatory effects. We reported previously that 8-OHD provoked reactive oxygen species (ROS) overproduction, and induced autophagy, apoptosis, breakpoint cluster region-Abelson murine leukemia viral oncogene (BCR-ABL) degradation, and differentiation in K562 human chronic myeloid leukemia (CML) cells. However, how 8-OHD regulates metabolism, the extracellular matrix during invasion and metastasis, and survival signaling pathways in CML remains largely unexplored. High-throughput technologies have been widely used to discover the therapeutic targets and pathways of drugs. Bioinformatics analysis of 8-OHD-downregulated differentially expressed genes (DEGs) revealed that Janus kinase/signal transducer and activator of transcription (JAK/STAT), matrix metalloproteinases (MMPs), c-Myc, phosphoinositide 3-kinase (PI3K)/AKT, and oxidative phosphorylation (OXPHOS) metabolic pathways were significantly altered by 8-OHD treatment. Western blot analyses validated that 8-OHD significantly downregulated cytosolic JAK2 and the expression and phosphorylation of STAT3 dose- and time-dependently in K562 cells. Zymography and transwell assays also confirmed that K562-secreted MMP9 and invasion activities were dose-dependently inhibited by 8-OHD after 24 h of treatment. RT-qPCR analyses verified that 8-OHD repressed metastasis and OXPHOS-related genes. In combination with DisGeNET, it was found that 8-OHD’s downregulation of PI3K/AKT is crucial for controlling CML development. A STRING protein–protein interaction analysis further revealed that AKT and MYC are hub proteins for cancer progression. Western blotting revealed that AKT phosphorylation and nuclear MYC expression were significantly inhibited by 8-OHD. Collectively, this systematic investigation revealed that 8-OHD exerts anti-CML effects by downregulating JAK/STAT, PI3K/AKT, MMP, and OXPHOS pathways, and MYC expression. These results could shed new light on the development of 8-OHD for CML therapy.

Nobiletin, a hexamethoxyflavonoid from citrus pomace, attenuates G1 cell cycle arrest and apoptosis in hypoxia-induced human trophoblast cells of JEG-3 and BeWo via regulating the p53 signaling pathway

Background

Hypoxia is associated with abnormal cell apoptosis in trophoblast cells, which causes fetal growth restriction and related placental pathologies. Few effective methods for the prevention and treatment of placenta-related diseases exist. Natural products and functional foods have always been a rich source of potential anti-apoptotic drugs. Nobiletin (NOB), a hexamethoxyflavonoid derived from the citrus pomace, shows an anti-apoptotic activity, which is a non-toxic constituent of dietary phytochemicals approved by the Food and Drug Administration. However, their effects on hypoxia-induced human trophoblast cells have not been fully studied.

Objective

The aim of this study was to investigate the protective effects of NOB on hypoxia-induced apoptosis of human trophoblast JEG-3 and BeWo cells, and their underlying mechanisms.

Design

First, the protective effect of NOB on hypoxia-induced apoptosis of JEG-3 and BeWo cells was studied. Cell viability and membrane integrity were determined by CCK-8 assay and lactate dehydrogenase activity, respectively. Real Time Quantitative PCR (RT-qPCR) and Western blot analysis were used to detect the mRNA and protein levels of HIF1α. Propidium iodide (PI)-labeled flow cytometry was used to detect cell cycle distribution. Cell apoptosis was detected by flow cytometry with Annexin V-FITC and PI double staining, and the expression of apoptosis marker protein cl-PARP was detected by Western blot analysis. Then, the molecular mechanism of NOB against apoptosis was investigated. Computer molecular docking and dynamics were used to simulate the interaction between NOB and p53 protein, and this interaction was verified in vitro by Ultraviolet and visible spectrum (UV-visible spectroscopy), fluorescence spectroscopy and circular dichroism. Furthermore, the changes in the expression of p53 signaling pathway genes and proteins were detected by RT-qPCR and Western blot analysis, respectively.

Results

Hypoxia treatment resulted in a decreased cell viability and cell membrane integrity in JEG-3 and BeWo cell lines, and an increased expression of HIF1α, cell cycle arrest in the G1 phase, and massive cell apoptosis, which were alleviated after NOB treatment. Molecular docking and dynamics simulations found that NOB spontaneously bonded to human p53 protein, leading to the change of protein conformation. The intermolecular interaction between NOB and human p53 protein was further confirmed by UV-visible spectroscopy, fluorescence spectroscopy and circular dichroism. After the treatment of 100 μM NOB, a down-regulation of mRNA and protein levels of p53 and p21 and an up-regulation of BCL2/BAX mRNA and protein ratio were observed in JEG-3 cells; however, there was also a down-regulation of mRNA and protein levels observed for p53 and p21 in BeWo cells after the treatment of NOB. The BCL2/BAX ratio of BeWo cells did not change after the treatment of 100 μM NOB.

Conclusion

NOB attenuated hypoxia-induced apoptosis in JEG-3 and BeWo cell lines and might be a potential functional ingredient to prevent pregnancy-related diseases caused by hypoxia-induced apoptosis. These findings would also suggest the exploration and utilization of citrus resources, and the development of citrus industry.

SOCS6 promotes radiosensitivity and decreases cancer cell stemness in esophageal squamous cell carcinoma by regulating c-Kit ubiquitylation

Background

Radiotherapy is a major treatment for esophageal squamous cell carcinoma (ESCC). However, HPV infection related radioresistance caused poor prognosis of ESCC. The function of SOCS6, which has been shown to be a tumor suppressor in several cancers, has not been fully investigated up till now. In this manuscript, we aim to further investigate the role of SOCS6 in regulating ESCC radioresistance.

Methods

Fifty-seven ESCC patients were enrolled for survival analysis. SOCS6 was stably overexpressed in HPV⁺ ESCC and ESCC cells, and cells were treated with radiation and then subjected to colony formation assays. Expression of DNA damage repair regulating proteins were examined by Western blotting. Cell growth, cell migration and cisplatin sensitivity were then analyzed. Sphere formation assays and flow cytometry were used to investigate changes in cancer stem cell (CSC) properties. Immunofluorescent staining and confocal microscopy were used to locate SOCS6 and c-Kit. Ubiquitylation level of c-Kit were analyzed after immunoprecipitation. Then, coimmunoprecipitation (CoIP) of SOCS6 and c-Kit were performed. In vivo, xenograft animal models were treated with radiation to examine the radiosensitivity.

Results

SOCS6 is correlated with better prognosis in ESCC patients. Radioresistance is impaired by SOCS6 upregulation, which inhibited cell growth, migration and increased sensitivity to cisplatin. SOCS6 significantly decreased the population of CSCs expressing the surface biomarker CD271 or CD24^low/CD44^high and their ability of sphere formation. SOCS6 and c-Kit were collocated in the cytoplasm. Blotting of ubiquitin and CoIP experiments indicated that the mechanism was related to ubiquitylation and degradation of the receptor c-Kit. Xenograft tumor mouse model showed that SOCS6 inhibited tumor growth and promoted radiosensitivity in vivo.

Conclusions

Our findings suggest that SOCS6 can promote the radiosensitivity of HPV⁺ ESCC and ESCC cells and reduce their stemness via ubiquitylation and degradation of c-Kit. Thus, SOCS6 is a potential target for overcoming radioresistance of ESCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-01859-2.

Effects of glycyrrhizin on the pharmacokinetics of nobiletin in rats and its potential mechanism

Context: Both nobiletin (NBL) and glycyrrhizin (GL) have anti-inflammatory and antitumor properties. These agents may be co-administered in the clinic. However, the drug-drug interaction between them is not clear.Objective: The drug-drug interaction between GL and NBL was investigated, to clarify the effect of GL on the pharmacokinetics of NBL, and its main mechanism.Materials and methods: The pharmacokinetic profiles of oral administration of NBL (50 mg/kg) in Sprague-Dawley rats of two groups with six each, with or without pre-treatment of GL (100 mg/kg/day for 7 days), were investigated. The effects of GL on the metabolic stability and transport of NBL were also investigated through the rat liver microsome and Caco-2 cell transwell models.Results: The results showed that GL significantly decreased the peak plasma concentration (from 1.74 ± 0.15 to 1.12 ± 0.10 μg/mL) and the t_1/2 (7.44 ± 0.65 vs. 5.92 ± 0.68) of NBL, and the intrinsic clearance rate of NBL was increased by the pre-treatment with GL (39.49 ± 2.5 vs. 48.29 ± 3.4 μL/min/mg protein). The Caco-2 cell transwell experiments indicated that GL could increase the efflux ratio of NBL from 1.61 to 2.41.Discussion and conclusion: These results indicated that GL could change the pharmacokinetic profile of NBL, via increasing the metabolism and efflux of NBL in rats. It also suggested that the dose of NBL should be adjusted when co-administrated with GL in the clinic.

8-Hydroxydaidzein, an Isoflavone from Fermented Soybean, Induces Autophagy, Apoptosis, Differentiation, and Degradation of Oncoprotein BCR-ABL in K562 Cells

8-Hydroxydaidzein (8-OHD, 7,8,4'-trihydoxyisoflavone) is a hydroxylated derivative of daidzein isolated from fermented soybean products. The aim of this study is to investigate the anti-proliferative effects and the underlying mechanisms of 8-OHD in K562 human chronic myeloid leukemia (CML) cells. We found that 8-OHD induced reactive oxygen species (ROS) overproduction and cell cycle arrest at the S phase by upregulating p21Cip1 and downregulating cyclin D2 (CCND2) and cyclin-dependent kinase 6 (CDK6) expression. 8-OHD also induced autophagy, caspase-7-dependent apoptosis, and the degradation of BCR-ABL oncoprotein. 8-OHD promoted Early Growth Response 1 (EGR1)-mediated megakaryocytic differentiation as an increased expression of marker genes, CD61 and CD42b, and the formation of multi-lobulated nuclei in enlarged K562 cells. A microarray-based transcriptome analysis revealed a total of 3174 differentially expressed genes (DEGs) after 8-OHD (100 μM) treatment for 48 h. Bioinformatics analysis of DEGs showed that hemopoiesis, cell cycle regulation, nuclear factor-κB (NF-κB), and mitogen-activated protein kinase (MAPK) and Janus kinase/signal transducers and activators of transcription (JAK-STAT)-mediated apoptosis/anti-apoptosis networks were significantly regulated by 8-OHD. Western blot analysis confirmed that 8-OHD significantly induced the activation of MAPK and NF-κB signaling pathways, both of which may be responsible, at least in part, for the stimulation of apoptosis, autophagy, and differentiation in K562 cells. This is the first report on the anti-CML effects of 8-OHD and the combination of experimental and in silico analyses could provide a better understanding for the development of 8-OHD on CML therapy.

Nobiletin in Cancer Therapy: How This Plant Derived-Natural Compound Targets Various Oncogene and Onco-Suppressor Pathways

Cancer therapy is a growing field, and annually, a high number of research is performed to develop novel antitumor drugs. Attempts to find new antitumor drugs continue, since cancer cells are able to acquire resistance to conventional drugs. Natural chemicals can be considered as promising candidates in the field of cancer therapy due to their multiple-targeting capability. The nobiletin (NOB) is a ubiquitous flavone isolated from Citrus fruits. The NOB has a variety of pharmacological activities, such as antidiabetes, antioxidant, anti-inflammatory, hepatoprotective, and neuroprotective. Among them, the antitumor activity of NOB has been under attention over recent years. In this review, we comprehensively describe the efficacy of NOB in cancer therapy. NOB induces apoptosis and cell cycle arrest in cancer cells. It can suppress migration and invasion of cancer cells via the inhibition of epithelial-to-mesenchymal transition (EMT) and EMT-related factors such as TGF-β, ZEB, Slug, and Snail. Besides, NOB inhibits oncogene factors such as STAT3, NF-κB, Akt, PI3K, Wnt, and so on. Noteworthy, onco-suppressor factors such as microRNA-7 and -200b undergo upregulation by NOB in cancer therapy. These onco-suppressor and oncogene pathways and mechanisms are discussed in this review.

Nobiletin Promotes Megakaryocytic Differentiation through the MAPK/ERK-Dependent EGR1 Expression and Exerts Anti-Leukemic Effects in Human Chronic Myeloid Leukemia (CML) K562 Cells

Differentiation therapy is an alternative strategy used to induce the differentiation of blast cells toward mature cells and to inhibit tumor cell proliferation for cancer treatment. Nobiletin (NOB), a polymethoxyflavone phytochemical, is present abundantly in citrus peels and has been reported to possess anti-cancer activity. In this study, we investigated the anti-leukemic effects of NOB on cell differentiation and its underlying mechanisms in human chronic myeloid leukemia (CML) K562 cells. NOB (100 μM) treatment for 24 and 48 h significantly decreased viability of K562 cells to 54.4 ± 5.3% and 46.2 ± 9.9%, respectively. NOB (10–100 μM) significantly inhibited cell growth in K562 cells. Flow cytometry analysis and immunoblotting data showed that NOB (40 and 80 μM) could modulate the cell cycle regulators including p21, p27, and cyclin D2, and induce G1 phase arrest. NOB also increased the messenger RNA (mRNA) and protein expression of megakaryocytic differentiation markers, such as CD61, CD41, and CD42 as well as the formation of large cells with multi-lobulated nuclei in K562 cells. These results suggested that NOB facilitated K562 cells toward megakaryocytic differentiation. Furthermore, microarray analysis showed that expression of EGR1, a gene associated with promotion of megakaryocytic differentiation, was markedly elevated in NOB-treated K562 cells. The knockdown of EGR1 expression by small interference RNA (siRNA) could significantly attenuate NOB-mediated cell differentiation. We further elucidated that NOB induced EGR1 expression and CD61 expression through increases in MAPK/ERK phosphorylation in K562 cells. These results indicate that NOB promotes megakaryocytic differentiation through the MAPK/ERK pathway-dependent EGR1 expression in human CML cells. In addition, NOB when combined with imatinib could synergistically reduce the viability of K562 cells. Our findings suggest that NOB may serve as a beneficial anti-leukemic agent for differentiation therapy.

Nobiletin, a citrus polymethoxyflavone, enhances the effects of bicalutamide on prostate cancer cells via down regulation of NF-κB, STAT3, and ERK activation

Natural products have shown potential to be combined with current cancer therapies to improve patient outcomes. Nobiletin (NBT) is a citrus polymethoxyflavone and has been shown to exert an anticancer effect in various cancer cells. We investigated the effects and mechanisms of NBT in combination with bicalutamide (BCT), a commonly used anti-androgen drug in prostate cancer therapy, on prostate cancer cells. Our results demonstrate that the combined treatment with NBT and BCT produces an enhanced inhibitory effect on the growth of prostate cancer cells compared to either compound alone. The synergistic action of NBT and BCT was confirmed using isobologram analysis. Moreover, this study has shown that NBT and BCT synergistically inhibited colony formation and migration as well as induced apoptosis. Mechanistic studies demonstrate that NBT and BCT combination reduced key cellular signaling regulators including: p-Erk/Erk, p-STAT3/STAT3 and NF-κB. Overall, these results suggest that NBT combination with BCT may be an effective treatment for prostate cancer.

DNA methylation-based prognostic biomarkers of acute myeloid leukemia patients

Background

Acute myeloid leukemia (AML) is a heterogeneous clonal disease that prevents normal myeloid differentiation with its common features. Its incidence increases with age and has a poor prognosis. Studies have shown that DNA methylation and abnormal gene expression are closely related to AML.

Methods

The methylation array data and mRNA array data are from the Gene Expression Omnibus (GEO) database. Through the GEO data, we identified differential genes from tumors and normal samples. Then we performed Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analyses on these differential genes. Protein-protein interaction (PPI) network construction and module analysis were performed to screen the highest-scoring modules. Next, we used SurvExpress software to analyze the genes in the highest-scoring module and selected potential prognostic genes by univariate and multivariate Cox analysis. Finally, the three genes screened by SurvExpress software were analyzed using the methylation analysis site MethSurv to explore AML associated methylation biomarkers.

Results

We found three genes that can be used as independent prognostic factors for AML. These three genes are the low expression/methylation genes ATP11A and ITGAM, and the high expression/low methylation gene ZNRF2.

Conclusions

In this study, we performed a comprehensive analysis of DNA methylation and gene expression to identify key epigenetic genes in AML.

Xanthohumol Suppresses NPC1L1 Gene Expression through Downregulation of HNF-4α and Inhibits Cholesterol Uptake in Caco-2 Cells

Xanthohumol (Xan) is a prenylated chalcone mainly found in hops; it has been demonstrated to function against hypercholesterolemia, hyperlipidemia, and atherosclerosis. In this study, we focused on the hypocholesterolemic effect of Xan on cholesterol uptake and the underlying molecular mechanisms of Xan in human intestinal Caco-2 cells. The microarray data showed that Niemann-Pick C1-like 1 (NPC1L1), an essential transporter for dietary cholesterol absorption, was significantly downregulated in Xan-treated Caco-2 cells. We demonstrated that Xan (10 and 20 μM) suppressed the mRNA and protein expression of NPC1L1 by 0.65 ± 0.12-fold and 0.54 ± 0.15-fold and 0.72 ± 0.04-fold and 0.44 ± 0.12-fold, respectively, compared to that of the vehicle-treated Caco-2 cells. Moreover, Xan (10 and 20 μM) significantly inhibited cholesterol uptake by approximately 12 and 32% in Caco-2 cells. NPC1L1 promoter activity was significantly suppressed by Xan, and a DNA element within the NPC1L1 promoter involved in Xan-mediated NPC1L1 reduction located between the -120 and -20 positions was identified. Moreover, Xan markedly decreased the mRNA and protein levels of hepatocyte nuclear factor 4α (HNF-4α), a critical activator of NPC1L1 transcription, and subsequently attenuated HNF-4α/NPC1L1 promoter complex formation, resulting in the suppression of NPC1L1 gene expression. Finally, we demonstrated that Xan markedly abolished lovastatin-induced NPC1L1 overexpression in Caco-2 cells. These findings reveal that Xan suppresses NPC1L1 expression via downregulation of HNF-4α and exerts inhibitory effects on cholesterol uptake in the intestinal Caco-2 cells. Our findings suggest Xan could serve as a potential cholesterol-lowering agent and supplement for statin therapy.