1.Clinical Biomarkers of Neurodegeneration in REM Sleep Behavior Disorder.
Junying ZHOU ; Jihui ZHANG ; Siu Ping LAM ; Xiangdong TANG ; Yun Kwok WING
Journal of Sleep Medicine 2015;12(2):27-33
Rapid eye movement sleep behavior disorder (RBD) is currently considered as a prodromal stage of alphasynucleinopathies neurodegeneration. The update data suggested that over 80% patients with idiopathic RBD eventually developed neurodegenerative disease after a mean of 14 years interval from the onset of RBD. A series of potential biomarkers have been identified to predict the development of neurodegeneration in idiopathic RBD, including olfactory loss, color vision deficit, depression, mild cognitive impairment, excessive daytime sleepiness, dopamine dysfunction, and tonic electromyographic activity. Early recognition of the predictive markers of neurodegeneration in idiopathic RBD is essential for development of intervention or prevention strategies at the presymptomatic stage. Nonetheless, the current literature is lacking biomarkers that might reflect the alpha-synuclein neuropathology at the earliest stages. Future studies with large samples and systematic follow-up are needed to confirm more potential markers of neurodegeneration at its early stages.
alpha-Synuclein
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Biomarkers*
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Color Vision
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Depression
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Dopamine
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Follow-Up Studies
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Humans
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Mild Cognitive Impairment
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Neurodegenerative Diseases
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Parkinson Disease
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Prodromal Symptoms
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REM Sleep Behavior Disorder*
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Sleep, REM*
2.Potential Perturbations of Critical Cancer-regulatory Genes in TripleNegative Breast Cancer Cells Within the Humanized Microenvironment of Patient-derived Xenograft Models
Yujeong HER ; Jihui YUN ; Hye-Youn SON ; Woohang HEO ; Jong-Il KIM ; Hyeong-Gon MOON
Journal of Breast Cancer 2024;27(1):37-53
Purpose:
In this study, we aimed to establish humanized patient-derived xenograft (PDX) models for triple-negative breast cancer (TNBC) using cord blood (CB) hematopoietic stem cells (HSCs). Additionally, we attempted to characterize the immune microenvironment of the humanized PDX model to understand the potential implications of altered tumorimmune interactions in the humanized PDX model on the behavior of TNBC cells.
Methods:
To establish a humanized mouse model, high-purity CD34+ HSCs from CB were transplanted into immunodeficient NOD scid γ mice. Peripheral and intratumoral immune cell compositions of humanized and non-humanized mice were compared. Additionally, RNA sequencing of the tumor tissues was performed to characterize the gene expression features associated with humanization.
Results:
After transplanting the CD34+ HSCs, CD45+ human immune cells appeared within five weeks. A humanized mouse model showed viable human immune cells in the peripheral blood, lymphoid organs, and in the tumor microenvironment. Humanized TNBC PDX models showed varying rates of tumor growth compared to that of non-humanized mice.RNA sequencing of the tumor tissue showed significant alterations in tumor tissues from the humanized models. tumor necrosis factor receptor superfamily member 11B (TNFRSF11B) is a shared downregulated gene in tumor tissues from humanized models. Silencing of TNFRSF11B in TNBC cell lines significantly reduced cell proliferation, migration, and invasion in vitro. Additionally, TNFRSF11B silenced cells showed decreased tumorigenicity and metastatic capacity in vivo.
Conclusion
Humanized PDX models successfully recreated tumor-immune interactions in TNBC. TNFRSF11B, a commonly downregulated gene in humanized PDX models, may play a key role in tumor growth and metastasis. Differential tumor growth rates and gene expression patterns highlighted the complexities of the immune response in the tumor microenvironment of humanized PDX models.
3.Protein Phosphatase 1H, Cyclin-Dependent Kinase Inhibitor p27, and Cyclin-Dependent Kinase 2 in Paclitaxel Resistance for Triple Negative Breast Cancers
Saem HUR ; Ju Hee KIM ; Jihui YUN ; Young Wook JU ; Jong Min HAN ; Woohang HEO ; Kwangsoo KIM ; Kyeonghun JEONG ; Han-Byoel LEE ; Wonshik HAN ; Dong-Young NOH ; Jong-Il KIM ; Hyeong-Gon MOON
Journal of Breast Cancer 2020;23(2):162-170
Purpose:
Paclitaxel is a cytotoxic chemotherapy commonly used in patients with triple negative breast cancer (TNBC); however, the resistance to paclitaxel is a cause of poor response in the patients. The aim of this study was to examine the role of protein phosphatase 1H (PPM1H) in paclitaxel resistance in breast cancer patients.
Methods:
To investigate the function of PPM1H in paclitaxel treatment, we conducted in vitro assays and molecular experiments using a stable cell line (MDA-MB-231) in which PPM1H is overexpressed. We also performed molecular analyses on patient tissue samples. Molecular expression related to PPM1H in breast cancer patients was analyzed using TCGA data.
Results:
We investigated whether PPM1H was associated with paclitaxel resistance in breast cancer. PPM1H expression was upregulated in breast cancer cells treated with paclitaxel. We also observed that overexpression of PPM1H in breast cancer cells resulted in increased sensitivity to paclitaxel in vitro. Additionally, paclitaxel treatment induced dephosphorylation of cyclin-dependent kinase (CDK) inhibitor p27 (p27), which was more evident in PPM1H-overexpressing cells. To understand how upregulation of PPM1H increases paclitaxel sensitivity, we determined the levels of p27, phospho-p27, and CDK2, since CDK2 exerts antagonistic effects against PPM1H on p27 phosphorylation. The patient-derived xenograft (PDX) tumors that did not respond to paclitaxel showed increased levels of CDK2 and phospho-p27 and decreased levels of total p27 compared to the other breast tumor tissues. The use of dinaciclib, a selective CDK inhibitor, significantly inhibited tumor growth in the PDX model.
Conclusion
CDK2 kinase activity was significantly upregulated in basal breast cancer tumors and was negatively correlated with p27 protein levels in the TCGA breast cancer dataset, suggesting that targeting CDK2 may be an effective treatment strategy for TNBC patients.
4.Self-microemulsifying drug delivery system for improving the bioavailability of huperzine A by lymphatic uptake.
Fang LI ; Rongfeng HU ; Bin WANG ; Yun GUI ; Gang CHENG ; Song GAO ; Lei YE ; Jihui TANG
Acta Pharmaceutica Sinica B 2017;7(3):353-360
Huperzine A (Hup-A) is a poorly water-soluble drug with low oral bioavailability. A self-microemulsifying drug delivery system (SMEDDS) was used to enhance the oral bioavailability and lymphatic uptake and transport of Hup-A. A single-pass intestinal perfusion (SPIP) technique and a chylomicron flow-blocking approach were used to study its intestinal absorption, mesenteric lymph node distribution and intestinal lymphatic uptake. The value of the area under the plasma concentration-time curve (AUC) of Hup-A SMEDDS was significantly higher than that of a Hup-A suspension (<0.01). The absorption rate constant () and the apparent permeability coefficient () for Hup-A in different parts of the intestine suggested a passive transport mechanism, and the values ofandof Hup-A SMEDDS in the ileum were much higher than those in other intestinal segments. The determination of Hup-A concentration in mesenteric lymph nodes can be used to explain the intestinal lymphatic absorption of Hup-A SMEDDS. For Hup-A SMEDDS, the values of AUC and maximum plasma concentration () of the blocking model were significantly lower than those of the control model (<0.05). The proportion of lymphatic transport of Hup-A SMEDDS and Hup-A suspension were about 40% and 5%, respectively, suggesting that SMEDDS can significantly improve the intestinal lymphatic uptake and transport of Hup-A.