Publications by authors named "Hyo Kyung Choi"

We sought to investigate the effect of rose petal extract (RPE) on the proliferation, migration, and invasion of cancer cells. RPE significantly inhibited the growth of lung and colorectal cancer cell lines, with rapid suppression of A549 lung cancer cells at low concentrations. These effects occurred concomitantly with downregulation of the cell proliferation mediators PCNA, cyclin D1, and c-myc.

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Targeting epigenetic changes in gene expression in cancer cells may offer new strategies for the development of selective cancer therapies. In the present study, we investigated coumestrol, a natural compound exhibiting broad anti-cancer effects against skin melanoma, lung cancer and colon cancer cell growth. Haspin kinase was identified as a direct target protein of coumestrol using kinase profiling analysis.

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Protein phosphatase 2Cβ (PP2Cβ) was found to act as a negative regulator of NF-κB-mediated inflammatory signaling; however, its regulatory mechanism has not been examined. Here, we show that protein kinase A (PKA) phosphorylates the PP2Cβ, which was inhibited by PKA-specific inhibitor, H89. Mutation analysis of serine residues in PP2Cβ revealed that Ser-195 in PP2Cβ is phosphorylated by PKA.

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Alzheimer's disease (AD) is the most common neurodegenerative disease to cause dementia in the elderly. Amyloid β (Aβ)-peptide induced oxidative stress causes the initiation and progression of AD. Recently, new chalcone derivatives termed the Chana series were synthesized.

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Background: Distal microsatellite instability (MSI)-high colorectal cancers (CRCs) have been investigated by few studies and are generally regarded as having similar features to proximal MSI-high CRCs. In the present study, we aimed to elucidate whether distal sporadic MSI-high CRCs displayed distinguished clinicopathological and molecular features from proximal MSI-high CRCs.

Methods: All patients who underwent their first surgical resections for stage I-IV sporadic CRCs between August 2003 and August 2006 were initially considered for enrollment, and their MSI data were prospectively collected.

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Goals: This study evaluated the significance of cystic fluid analysis and radiologic findings in the differential diagnosis of biliary cystadenomas (BCA) and hepatic simple cysts (HSCs).

Background: BCA are premalignant lesions. The treatment of choice is surgical excision.

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Background: The biologic significance of low-level microsatellite instability (MSI) in colorectal cancers (CRCs) remains unclear. This study aimed to elucidate whether sporadic MSI-low CRCs in Korea displayed distinguished clinicopathological characteristics from microsatellite stable (MSS) and MSI-high CRCs.

Methods: We consecutively enrolled 657 patients who underwent their first surgical resections for stage I-IV sporadic CRCs and compared their clinicopathological features and prognosis after resection according to MSI status (574 MSS, 30 MSI-low and 53 MSI-high CRCs).

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