• 대한의생명과학회지
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• 제14권4호
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• pp.243-248
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• 2008

The Forkhead box M1 (FoxM1) has been shown to regulate transcription of cell cycle genes essential for $G_1$-S and $G_2$-M progression, including $p27^{kip1}$. The $p27^{kip1}$ gene is a member of the universal cyclin-dependent kinase inhibitor family. Immunohistochemical studies for FoxM1 and $p27^{kip1}$ were performed in 154 lung cancers (69 squamous cell carcinomas (SCC) and 85 adenocarcinomas (ADC)). Immunoreactivity for FoxM1 and $p27^{kip1}$ were found in 79 (51.3%) and 49 (31.8%) out of 154 cases, respectively. Forty-six (58.2%) of the 79 cases with a positive FoxM1 immunoreactivity showed a negative $p27^{kip1}$ expression in 154 lung cancers. According to histologic type, 22 (53.7%) of the 41 SCC cases with a positive FoxM1 immunoreactivity showed a negative $p27^{kip1}$ expression and 24 (63.2%) of the 38 ADC cases with a positive FoxM1 immunoreactivity showed a negative $p27^{kip1}$ expression. The expression of $p27^{kip1}$ was significantly higher in the SCC than in the ADC (P=0.050). There were no significant associations between the FoxM1 and $p27^{kip1}$ expressions and other clinicopathologic factors. These findings suggest that FoxM1 overexpression may diminish the expression of $p27^{kip1}$ protein in lung cancers. Further studies are needed to define the relation between FoxM1 and $p27^{kip1}$ for examining the mechanisms of tissue-specific FoxM1 expression.

• The Plant Pathology Journal
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• 제30권2호
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• pp.136-150
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• 2014

Although multiple transcription factors (TFs) have been characterized via mutagenesis to understand their roles in controlling pathogenicity and infection-related development in Magnaporthe oryzae, the causal agent of rice blast, if and how forkhead-box (FOX) TFs contribute to these processes remain to be characterized. Four putative FOX TF genes were identified in the genome of M. oryzae, and phylogenetic analysis suggested that two of them (MoFKH1 and MoHCM1) correspond to Ascomycota-specific members of the FOX TF family while the others (MoFOX1 and MoFOX2) are Pezizomycotina-specific members. Deletion of MoFKH1 (${\Delta}Mofkh1$) resulted in reduced mycelial growth and conidial germination, abnormal septation and stress response, and reduced virulence. Similarly, ${\Delta}Mohcm1$ exhibited reduced mycelial growth and conidial germination. Conidia of ${\Delta}Mofkh1$ and ${\Delta}Mohcm1$ were more sensitive to one or both of the cell cycle inhibitors hydroxyurea and benomyl, suggesting their role in cell cycle control. On the other hand, loss of MoFOX1 (${\Delta}Mofox1$) did not show any noticeable changes in development, pathogenicity, and stress response. Deletion of MoFOX2 was not successful even after repeated attempts. Taken together, these results suggested that MoFKH1 and MoHCM1 are important in fungal development and that MoFKH1 is further implicated in pathogenicity and stress response in M. oryzae.

• BMB Reports
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• 제52권3호
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• pp.208-213
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• 2019

Chemoresistance is the primary obstacle in the treatment of locally advanced and metastatic nasopharyngeal carcinoma (NPC). Recent evidence suggests that the transcription factor forkhead box M1 (FoxM1) is involved in chemoresistance. Our group previously confirmed that FoxM1 is overexpressed in NPC. In this study, we investigated the role of FoxM1 in cisplatin resistance of the cell lines 5-8F and HONE-1 and explored its possible mechanism. Our results showed that FoxM1 and NBS1 were both overexpressed in NPC tissues based on data from the GSE cohort (GSE12452). Then, we measured FoxM1 levels in NPC cells and found FoxM1 was overexpressed in NPC cell lines and could be stimulated by cisplatin. MTT and clonogenic assays, flow cytometry, ${\gamma}H2AX$ immunofluorescence, qRT-PCR, and western blotting revealed that downregulation of FoxM1 sensitized NPC cells to cisplatin and reduced the repair of cisplatin-induced DNA double-strand breaks via inhibition of the MRN (MRE11-RAD50-NBS1)-ATM axis, which might be related to the ability of FoxM1 to regulate NBS1. Subsequently, we demonstrated that enhanced sensitivity of FoxM1 knockdown cells could be reduced by overexpression of NBS1. Taken together, our data demonstrate that downregulation of FoxM1 could improve the sensitivity of NPC cells to cisplatin through inhibition of MRN-ATM-mediated DNA repair, which could be related to FoxM1-dependent regulation of NBS1.

• Animal Bioscience
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• 제34권7호
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• pp.1210-1220
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• 2021

Objective: Unlike mammals, goose fatty liver shows a strong tolerance to fatty acids without obvious injury. Stearyl-coenzyme A desaturase 1 (SCD1) serves crucial role in desaturation of saturated fatty acids (SAFs), but its role in the SAFs tolerance of goose hepatocytes has not been reported. This study was conducted to explore the role of SCD1 in regulating palmitic acid (PA) tolerance of goose primary hepatocytes. Methods: 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide was examined to reflect the effect of PA on hepatocytes viability, and quantitative polymerase chain reaction was used to detect the mRNA levels of several genes related to endoplasmic reticulum (ER) stress, inflammation, and apoptosis, and the role of SCD1 in PA tolerance of goose hepatocytes was explored using RNA interfere. Results: Our results indicated that goose hepatocytes exhibited a higher tolerant capacity to PA than human hepatic cell line (LO2 cells). In goose primary hepatocytes, the mRNA levels of fatty acid desaturation-related genes (SCD1 and fatty acid desaturase 2) and fatty acid elongate enzyme-related gene (elongase of very long chain fatty acids 6) were significantly upregulated with 0.6 mM PA treatment. However, in LO2 cells, expression of ER stress-related genes (x box-binding protein, binding immunoglobulin protein, and activating transcription factor 6), inflammatory response-related genes (interleukin-6 [IL-6], interleukin-1β [IL-1β], and interferon-γ) and apoptosis-related genes (bcl-2-associated X protein, b-cell lymphoma 2, Caspase-3, and Caspase-9) was significantly enhanced with 0.6 mM PA treatment. Additionally, small interfering RNA (siRNA) mediated downregulation of SCD1 significantly reduced the PA tolerance of goose primary hepatocytes under the treatment of 0.6 mM PA; meanwhile, the mRNA levels of inflammatory-related genes (IL-6 and IL-1β) and several key genes involved in the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT), forkhead box O1 (FoxO1), mammalian target of rapamycin and AMPK pathways (AKT1, AKT2, FoxO1, and sirtuin 1), as well as the protein expression of cytochrome C and the apoptosis rate were upregulated. Conclusion: In conclusion, our data suggested that SCD1 was involved in enhancing the PA tolerance of goose primary hepatocytes by regulating inflammation- and apoptosis-related genes expression.

• The Korean Journal of Physiology and Pharmacology
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• 제24권2호
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• pp.149-156
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• 2020

Sodium 2-mercaptoethanesulfonate (mesna) is a protective agent that is widely used in medicine because of its antioxidant effects. Recently, reactive oxygen species (ROS) were shown to increase pigmentation. Thus, ROS scavengers and inhibitors of ROS production may suppress melanogenesis. Forkhead box-O3a (FoxO3a) is an antimelanogenic factor that mediates ROS-induced skin pigmentation. In this study, we aimed to investigate the whitening effect of mesna and the signaling mechanism mediating this effect. Human melanoma (MNT-1) cells were used in this study. mRNA and protein expression were measured by real-time quantitative PCR and Western blotting analysis to track changes in FoxO3a-related signals induced by mesna. An immunofluorescence assay was performed to determine the nuclear translocation of FoxO3a. When MNT-1 melanoma cells were treated with mesna, melanin production and secretion decreased. These effects were accompanied by increases in FoxO3a activation and nuclear translocation, resulting in downregulation of four master genes of melanogenesis: MITF, TYR, TRP1, and TRP2. We found that mesna, an antioxidant and radical scavenger, suppresses melanin production and may therefore be a useful agent for the clinical treatment of hyperpigmentation disorders.

• Journal of Microbiology and Biotechnology
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• 제33권12호
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• pp.1635-1647
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• 2023

Muscle atrophy, which is defined as a decrease in muscle mass and strength, is caused by an imbalance between the anabolism and catabolism of muscle proteins. Thus, modulating the homeostasis between muscle protein synthesis and degradation represents an efficient treatment approach for this condition. In the present study, the protective effects against muscle atrophy of ethanol extracts of Morus alba L. (MA) and Angelica keiskei Koidz. (AK) leaves and their mixtures (MIX) were evaluated in vitro and in vivo. Our results showed that MIX increased 5-aminoimidazole-4-carboxamide ribonucleotide-induced C2C12 myotube thinning, and enhanced soleus and gastrocnemius muscle thickness compared to each extract alone in dexamethasone-induced muscle atrophy Sprague Dawley rats. In addition, although MA and AK substantially improved grip strength and histological changes for dexamethasone-induced muscle atrophy in vivo, the efficacy was superior in the MIX-treated group. Moreover, MIX further increased the expression levels of myogenic factors (MyoD and myogenin) and decreased the expression levels of E3 ubiquitin ligases (atrogin-1 and muscle-specific RING finger protein-1) in vitro and in vivo compared to the MA- and AK-alone treatment groups. Furthermore, MIX increased the levels of phosphorylated phosphoinositide 3-kinase (PI3K), protein kinase B (Akt), and mammalian target of rapamycin (mTOR) that were reduced by dexamethasone, and downregulated the expression of forkhead box O3 (FoxO3a) induced by dexamethasone. These results suggest that MIX has a protective effect against muscle atrophy by enhancing muscle protein anabolism through the activation of the PI3K/Akt/mTOR signaling pathway and attenuating catabolism through the inhibition of FoxO3a.