Junctional adhesion molecule-like protein as a novel target for kaempferol to ameliorate lung adenocarcinoma / 中西医结合学报

OBJECTIVE@#Although there have been improvements in targeted therapy and immunotherapy, the majority of lung adenocarcinoma (LUAD) patients still lack effective therapies. Consequently, it is urgent to screen for new diagnosis biomarkers and pharmacological targets. Junctional adhesion molecule-like protein (JAML) was considered to be an oncogenic protein and may be a novel therapeutic target in LUAD. Kaempferol is a natural flavonoid that exhibits antitumor activities in LUAD. However, the effect of kaempferol on JAML is still unknown.@*METHODS@#Small interfering RNA was used to knockdown JAML expression. The cell viability was determined using the cell counting kit-8 assay. The proliferation of LUAD cells was evaluated using the 5-ethynyl-2'-deoxyuridine incorporation assay. The migration and invasion of LUAD cells were evaluated by transwell assays. Molecular mechanisms were explored by Western blotting.@*RESULTS@#JAML knockdown suppressed proliferation, migration and invasion of LUAD cells, and JAML deficiency restrained epithelial-mesenchymal transition (EMT) via inactivating the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway. Using a PI3K activator (740Y-P), rescue experiments showed that phenotypes to JAML knockdown in LUAD cells were dependent on the PI3K/AKT/mTOR pathway. Kaempferol also inhibited proliferation, migration and invasion of A549 and H1299 cells and partially suppressed EMT through the PI3K/AKT/mTOR pathway. Knockdown of JAML ameliorated the inhibitory effect of kaempferol on LUAD cells. Kaempferol exerted anticancer effects by targeting JAML.@*CONCLUSION@#JAML is a novel target for kaempferol against LUAD cells. Please cite this article as: Wu Q, Wang YB, Che XW, Wang H, Wang W. Junctional adhesion molecule-like protein as a novel target for kaempferol to ameliorate lung adenocarcinoma. J Integr Med. 2023; 21(3): 268-276.

Inhibitory Effect of Kaempferol on Proliferation of KG1a Cells and Its Mechanism / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of kaempferol on proliferation of acute myeloid leukemia (AML) KG1a cells and its mechanism.@*METHODS@#Human AML KG1a cells in logarithmic growth stage were taken and set at 25, 50, 75 and 100 μg/ml kaempferol group, another normal control group (complete medium without drug) and solvent control group (add dimethyl sulfoxide) were also set. After 24 and 48 hours of intervention, the cell proliferation rate was detected by CCK-8 assay. In addition, interleukin-6 (IL-6) combined with kaempferol group (Plus 20 μg/l IL-6 and 75 μg/ml kaempferol) was set up, 48 hours after culture, the cell cycle and apoptosis of KG1a cells were detected by flow cytometry, the mitochondrial membrane potential (MMP) of KG1a cells was detected by MMP detection kit (JC-1 method), and the expression of Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway related proteins in KG1a cells were detected by Western blot.@*RESULTS@#The cell proliferation rate of 25, 50, 75 and 100 μg/ml kaempferol group decreased significantly (P<0.05), and with the increase of kaempferol dose (r24 h=-0.990, r48 h= -0.999), the cell proliferation rate decreased gradually (P<0.05). The inhibitory effect of 75 μg/ml kaempferol on cell proliferation reached half of effective dose after 48 hours of intervention. Compared with normal control group, the G0/G1 phase cell proportion and apoptosis rate of cells in 25, 50 and 75 μg/ml kaempferol group increased, while the S phase cell proportion, MMP, phosphorylated JAK2 (p-JAK2)/JAK2 and phosphorylated STAT3 (p-STAT3)/STAT3 protein expression decreased in a dose-dependent manner (r=0.998, 0.994, -0.996, -0.981, -0.997, -0.930). Compared with 75 μg/ml kaempferol group, the G0/G1 phase cell proportion and apoptosis rate of cells in IL-6 combined with kaempferol group decreased, while the S phase cell proportion, MMP, p-JAK2/JAK2 and p-STAT3/STAT3 protein expression increased significantly (P<0.05).@*CONCLUSION@#Kaempferol can inhibit KG1a cell proliferation and induce KG1a cell apoptosis, its mechanism may be related to the inhibition of JAK2/STAT3 signal pathway.

Estudo do potencial antiviral sobre Sars Cov-2 dos compostos identificados nas folhas do extrato bruto de Eugenia pyriformis / Study of the antiviral potential on Sars Cov-2 of compounds identified in the leaves of the gross extract of Eugenia pyriformis / Estudio del potencial antiviral sobre Sars Cov-2 de los compuestos identificados en las hojas del extracto crudo de Eugenia pyriformis

Eugenia pyriformis Cambess (Myrtaceae), conhecida popularmente como uvaia. Em seus frutos são encontrados compostos fenólicos com ação antioxidante e nas folhas foram detectados altos teores de flavonoides e taninos hidrolisados que se mostraram inibidor da protease de 2019 - nCoV e SARS-CoV. Neste sentido, o objetivo deste estudo foi a obtenção do extrato bruto das folhas, a análise da composição química e a possibilidade da ação antiviral frente ao SARS COV-2. O extrato bruto (EB) foi obtido a partir das folhas secas de E. pyriformis, pela técnica de maceração dinâmica com esgotamento do solvente (etanol 90º GL) e concentrado em evaporador rotativo. Seis gramas do EB foram fracionados em cromatografia em coluna, e eluído com hexano, diclorometano, acetato de etila e metanol, as frações foram concentradas em um evaporador rotativo (Tecnal TE-210). O EB e as frações foram identificadas por cromatografia líquida de alta eficiência à espectrometria de massas de alta resolução (CLAE-ESI/qTOF). A identificação química do extrato bruto e frações das folhas de E. pyriformis evidenciou a presença de compostos fenólicos destacando os ácidos fenólicos, flavonoides e taninos. De forma complementar, foi realizado um levantamento bibliográfico sobre a provável ação antiviral dos compostos fenólicos e taninos presentes nas folhas de uvaia. Os resultados evidenciaram que os flavonoides quercetina e kaempferol possuem ação antiviral quando se ligam a glicoproteína do envelope ou capsídeo viral interferindo na ligação e penetração do vírus na célula. Este resultado coloca as folhas de E. pyriformis na lista de plantas com ação antiviral.

Eugenia pyriformis Cambess (Myrtaceae), popularly known as uvaia. In its fruits, phenolic compounds with antioxidant action are found and in the leaves, high levels of flavonoids and hydrolyzed tannins were detected, which proved to be an inhibitor of the 2019 protease - nCoV and SARS-CoV. In this sense, the objective of this study was to obtain the crude extract of the leaves, the analysis of the chemical composition and the possibility of antiviral action against SARS COV-2. The crude extract (EB) was obtained from the dried leaves of E. pyriformis, by the dynamic maceration technique with solvent exhaustion (ethanol 90º GL) and concentrated in a rotary evaporator. Six grams of EB were fractionated in column chromatography, and eluted with hexane, dichloromethane, ethyl acetate and methanol, the fractions were concentrated on a rotary evaporator (Tecnal TE-210). EB and fractions were identified by high performance liquid chromatography using high resolution mass spectrometry (HPLC-ESI/qTOF). The chemical identification of the crude extract and fractions of E. pyriformis leaves evidenced the presence of phenolic compounds, highlighting phenolic acids, flavonoids and tannins. In addition, a bibliographic survey was carried out on the probable antiviral action of phenolic compounds and tannins present in uvaia leaves. The results showed that the flavonoids quercetin and kaempferol have antiviral action when they bind to the envelope glycoprotein or viral capsid, interfering with the binding and penetration of the virus into the cell. This result places E. pyriformis leaves in the list of plants with antiviral action.

Eugenia pyriformis Cambess (Myrtaceae), conocida popularmente como uvaia. En sus frutos se encuentran compuestos fenólicos con acción antioxidante y en las hojas se detectaron altos contenidos de flavonoides y taninos hidrolizados que demostraron inhibir la proteasa de 2019 - nCoV y SARS-CoV. En este sentido, el objetivo de este estudio fue obtener el extracto crudo de las hojas, el análisis de la composición química y la posibilidad de acción antiviral contra el SARS COV-2. El extracto crudo (EB) se obtuvo a partir de las hojas secas de E. pyriformis, mediante la técnica de maceración dinámica con agotamiento del disolvente (etanol 90º GL) y se concentró en evaporador rotatorio. Seis gramos de EB se fraccionaron en cromatografía en columna, y se eluyeron con hexano, diclorometano, acetato de etilo y metanol, las fracciones se concentraron en un evaporador rotatorio (Tecnal TE-210). El EB y las fracciones se identificaron mediante cromatografía líquida de alta resolución a espectrometría de masas de alta resolución (HPLC-ESI/qTOF). La identificación química del extracto crudo y de las fracciones de las hojas de E. pyriformis mostró la presencia de compuestos fenólicos destacando los ácidos fenólicos, los flavonoides y los taninos. De forma complementaria, se realizó un estudio bibliográfico sobre la probable acción antiviral de los compuestos fenólicos y los taninos presentes en las hojas de la uva. Los resultados mostraron que los flavonoides quercetina y kaempferol tienen acción antiviral cuando se unen a la glicoproteína de la envoltura o cápside viral, interfiriendo en la unión y penetración del virus en la célula. Este resultado sitúa a las hojas de E. pyriformis en la lista de plantas con acción antiviral.

Kaempferol suppresses human gastric cancer SNU-216 cell proliferation, promotes cell autophagy, but has no influence on cell apoptosis

Gastric cancer remains a serious threat to human health worldwide. Kaempferol is a plant-derived flavonoid compound with a wide range of pharmacological activities. This study aimed to investigate the effects of kaempferol on gastric cancer SNU-216 cell proliferation, apoptosis, and autophagy, as well as underlying potential mechanisms. Viability, proliferation, and apoptosis of SNU-216 cells after kaempferol treatment were evaluated using cell counting kit-8 assay, 5-btomo-2′-deoxyuridine incorporation assay, and annexin V-FITC/PI staining, respectively. Quantitative reverse transcription PCR was performed to measure the mRNA expressions of cyclin D1 and microRNA-181a (miR-181a) in SNU-216 cells. Cell transfection was used to down-regulate the expression of miR-181a. The protein expression levels of cyclin D1, bcl-2, bax, caspase 3, caspase 9, autophagy-related gene 7, microtubule-associated protein 1 light chain 3-I (LC3-I), LC3-II, Beclin 1, p62, mitogen-activated protein kinase (MAPK), extracellular regulated protein kinases (ERK), and phosphatidylinositol 3 kinase (PI3K) in SNU-216 cells were detected using western blotting. Results showed that kaempferol significantly suppressed SNU-216 cell viability and proliferation but had no influence on cell apoptosis. Further results suggested that kaempferol significantly induced SNU-216 cell autophagy. The expression of miR-181a in SNU-216 cells after kaempferol treatment was enhanced. Kaempferol significantly inactivated MAPK/ERK and PI3K pathways in SNU-216 cells. Suppression of miR-181a significantly reversed the kaempferol-induced MAPK/ERK and PI3K pathways inactivation in SNU-216 cells. This research demonstrated that kaempferol suppressed proliferation and promoted autophagy of human gastric cancer SNU-216 cells by up-regulating miR-181a and inactivating MAPK/ERK and PI3K pathways.

Kaempferol inhibited VEGF and PGF expression and in vitro angiogenesis of HRECs under diabetic-like environment

Diabetic retinopathy (DR) is one of the common and specific microvascular complications of diabetes. This study aimed to investigate the anti-angiogenic effect of kaempferol and explore its underlying molecular mechanisms. The mRNA expression level of vascular endothelial growth factor (VEGF) and placenta growth factor (PGF) and the concentrations of secreted VEGF and PGF were measured by qTR-PCR and ELISA assay, respectively. Human retinal endothelial cells (HRECs) proliferation, migration, and sprouting were measured by CCK-8 and transwell, scratching wound, and tube formation assays, respectively. Protein levels were determined by western blot. High glucose (25 mM) increased the mRNA expression levels of VEGF and PGF as well as the concentrations of secreted VEGF and PGF in HRECs, which can be antagonized by kaempferol (25 µM). Kaempferol (5-25 µM) significantly suppressed cell proliferation, migration, migration distance and sprouting of HRECs under high glucose condition. The anti-angiogenic effect of kaempferol was mediated via downregulating the expression of PI3K and inhibiting the activation of Erk1/2, Src, and Akt1. This study indicates that kaempferol suppressed angiogenesis of HRECs via targeting VEGF and PGF to inhibit the activation of Src-Akt1-Erk1/2 signaling pathway. The results suggest that kaempferol may be a potential drug for better management of DR.

2,3,7,8-Tetrachlorodibenzo-P-Dioxin Induced Cell-Specific Drug Transporters With Acquired Cisplatin Resistance in Cisplatin Sensitive Cancer Cells

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) can induce drug transporter genes such as the ATP-binding cassette G member 2 (ABCG2), which contributes to multidrug resistance. We investigated the effect of TCDD pretreatment on drug transporters induction from cancer cells of various origins. Cell viabilities after treatment of cisplatin were measured to evaluate acquiring cisplatin resistance by TCDD. Acquring cisplatin resistance was found only in cisplatin senstivie cancer cells including gastric SNU601, colon LS180, brain CRT-MG and lymphoma Jurkat cells which showed a significant increase in cell viability after combined treatment with TCDD and cisplatin. High increase of ABCG2 gene expression was found in SNU601 and LS180 cells with a mild increase in the expression of the ABCC3, ABCC5,and SLC29A2 genes in SNU601 cells, and of major vault protein (MVP) in LS180 cells. The AhR inhibitor kaempferol suppressed the upregulation of ABCG2 expression and reversed the TCDD-induced increase in cell viability in LS180 cells. However, in CRT-MG cells, other transporter genes including ABCC1, ABCC5, ABCA3, ABCA2, ABCB4, ABCG1, and SLC29A1 were up-regulated. These findings suggested the acquiring cisplatin resistance by TCDD associated with cancer cell-type-specific induction of drug transporters.

2,3,7,8-Tetrachlorodibenzo-P-Dioxin Induced Cell-Specific Drug Transporters With Acquired Cisplatin Resistance in Cisplatin Sensitive Cancer Cells

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) can induce drug transporter genes such as the ATP-binding cassette G member 2 (ABCG2), which contributes to multidrug resistance. We investigated the effect of TCDD pretreatment on drug transporters induction from cancer cells of various origins. Cell viabilities after treatment of cisplatin were measured to evaluate acquiring cisplatin resistance by TCDD. Acquring cisplatin resistance was found only in cisplatin senstivie cancer cells including gastric SNU601, colon LS180, brain CRT-MG and lymphoma Jurkat cells which showed a significant increase in cell viability after combined treatment with TCDD and cisplatin. High increase of ABCG2 gene expression was found in SNU601 and LS180 cells with a mild increase in the expression of the ABCC3, ABCC5,and SLC29A2 genes in SNU601 cells, and of major vault protein (MVP) in LS180 cells. The AhR inhibitor kaempferol suppressed the upregulation of ABCG2 expression and reversed the TCDD-induced increase in cell viability in LS180 cells. However, in CRT-MG cells, other transporter genes including ABCC1, ABCC5, ABCA3, ABCA2, ABCB4, ABCG1, and SLC29A1 were up-regulated. These findings suggested the acquiring cisplatin resistance by TCDD associated with cancer cell-type-specific induction of drug transporters.

Cassia alata leaf extract induces cytotoxicity in A549 lung cancer cells via a mechanism that is caspase 8 dependent / El extracto de la hoja de cassia alata induce citotoxicidad en las células A549 del cáncer pulmonar humano a través de un mecanismo dependiente de la caspasa 8

OBJECTIVE: To evaluate the cytotoxic effect of a hexane extract of Cassia alata leaves in A549 lung cancer cells. METHOD: Parental A549 lung cancer cells were exposed to various concentrations (100"180 µg/ml) of Cassia alata leaf extract for 24 hours. Following treatment, the cells were evaluated using the 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay to determine the cytotoxic effect of the extract. Caspase 8, 3 and 9 negative A549 cells were also prepared using lentiviral based shRNA knockdown of the caspase 8, 3 and 9 genes, respectively. The cytotoxic effect of Cassia alata leaf extract was then evaluated in these knockdown cells using the MTT assay. Chemical analysis was performed on the extract using high performance liquid chromatography (HPLC). RESULTS: Cassia alata extract was cytotoxic in parental and caspase-9 negative, but not caspase 3 and 8 negative A549 cells. The IC50 values were 143 µg/ml and 145 µg/ml in parental and caspase 9 negative A549 cells respectively. The flavanoid kaempferol was identified as a constituent of Cassia alata leaf extract. CONCLUSIONS: Cassia alata produces cytotoxicity in A549 cancer cells that is mediated by caspase 8 activation. This effect may be attributable to kaempferol.

OBJETIVO: Evaluar el efecto citotóxico de un extracto de hexano de hojas de Cassia alata en las células A549 del cáncer pulmonar. MÉTODO: Células A549 parentales del cáncer pulmonar fueron expuestas a varias concentraciones (100-180 µg/ml) de un extracto de la hoja de Cassia alatadurante 24 horas. Tras el tratamiento, las células fueron evaluadas usando el ensayo de bromuro de 3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazolio (MTT) a fin de determinar el efecto citotóxico del extracto. También se prepararon células A549 negativas caspasa 8, 3 y 9 mediante silenciamiento génico vía ARN (shRNA knockdown) de los genes de las caspasas 8, 3 y 9 respectivamente, sobre la base de la inserción de vectores lentivirales. Entonces, usando un ensayo MTT se procedió a evaluar el efecto citotóxico del extracto de hojas de Cassia alataen éstas células genéticamente modificadas. Se realizó un análisis químico del extracto utilizando cromatografía líquida de alta eficacia. (HPLC). RESULTADOS: El extracto de Cassia alata resultó ser citotóxico en las células A549 negativas parentales y caspasa 9, pero no en las negativas caspasa 3 y 8. Los valores de IC50 fueron 143 µg/ml y 145 µg/ml en las células A549 negativas parentales y caspasa 9 respectivamente. El flavonol kaempferol fue identificado como un constituyente del extracto de las hojas de Cassia alata. CONCLUSIONES: La Cassia alata produce citotoxicidad en las células cancerosas A549, mediada por la activación de la caspasa 8. Este efecto puede ser atribuido al kaempferol.

Antiproliferation and Redifferentiation in Thyroid Cancer Cell Lines by Polyphenol Phytochemicals

Thyroid carcinogenesis is accompanied by loss of thyroid-specific functions and refractory to radioiodine and thyroid stimulating hormone (TSH) suppression therapy. Redifferentiating agents have been shown to inhibit tumor growth and improve the response to conventional therapy. Polyphenol phytochemicals (PPs) in fruits and vegetables have been reported to inhibit cancer initiation, promotion, progression and induce redifferentiation in selected types. In this study we examined PPs induce redifferentiation in thyroid cancer cell lines. We investigated the effects of genistein, resveratrol, quercetin, kaempferol, and resorcinol on the F9 embryonal carcinoma cell differentiation model. The thyroid cancer cell lines, TPC-1, FTC-133, NPA, FRO, and ARO, displayed growth inhibition in response to genistein, resveratrol, quercetin. We further demonstrated that genistein decreased the dedifferention marker CD97 in NPA cells and resveratrol decreased CD97 in FTC-133, NPA, FRO cells and quercetin decreased CD97 in all cell lines. We observed increased expression of differentiation marker NIS in FTC-133 cells in response to genistein, and resveratrol but no change in NPA, FRO, ARO cells. Quercetin increased or induced NIS in FTC-133, NPA, FRO cells. These findings suggest that PPs may provide a useful therapeutic intervention in thyroid cancer redifferentiation therapy.

Transcriptional profiling in human HaCaT keratinocytes in response to kaempferol and identification of potential transcription factors for regulating differential gene expression

Kaempferol is the major flavonol in green tea and exhibits many biomedically useful properties such as antioxidative, cytoprotective and anti-apoptotic activities. To elucidate its effects on the skin, we investigated the transcriptional profiles of kaempferol-treated HaCaT cells using cDNA microarray analysis and identified 147 transcripts that exhibited significant changes in expression. Of these, 18 were up-regulated and 129 were down-regulated. These transcripts were then classified into 12 categories according to their functional roles: cell adhesion/cytoskeleton, cell cycle, redox homeostasis, immune/defense responses, metabolism, protein biosynthesis/modification, intracellular transport, RNA processing, DNA modification/ replication, regulation of transcription, signal transduction and transport. We then analyzed the promoter sequences of differentially-regulated genes and identified over-represented regulatory sites and candidate transcription factors (TFs) for gene regulation by kaempferol. These included c-REL, SAP-1, Ahr-ARNT, Nrf-2, Elk-1, SPI-B, NF-kappaB and p65. In addition, we validated the microarray results and promoter analyses using conventional methods such as real-time PCR and ELISA-based transcription factor assay. Our microarray analysis has provided useful information for determining the genetic regulatory network affected by kaempferol, and this approach will be useful for elucidating gene-phytochemical interactions.