Proposed mechanism in the change of cellular composition in the outer medullary collecting duct during potassium homeostasis.

Park, E-Y,Kim, W-Y,Kim, Y-M,Lee, J-H,Han, K-H,Weiner, I D,Kim, J Gutenberg 2012 HISTOLOGY AND HISTOPATHOLOGY Vol.27 No.12

<P>Potassium depletion (K?-D) induces hypertrophy and hyperplasia of collecting duct cells, and potassium repletion (K?-R) induces regression of these changes. The purpose of this study was to examine the time courses of the changes in cellular composition, the origin of intercalated cells (ICs) and the mechanism responsible for these changes. SD rats received K?-depleted diets for 1, 7, or 14 days. After K?-D for 14 days some of the rats received normal diets for 1, 3, 5, or 7 days. In the inner stripe of the outer medulla, K?-D increased significantly the number and proportion of H?-ATPase-positive ICs, but decreased the proportion of H?-ATPase-negative principal cells (PCs). However, proliferation was limited to H?-ATPase-negative PCs. During K?-R, the cellular composition was recovered to control level. Apoptosis increased during K?-R and exclusively limited in H?-ATPase-negative PCs. Double immunolabeling with antibodies to PC and IC markers identified both cells negative or positive for all markers during both K?-D and K?-R. Electron microscopic observation showed that ultrastructure of AE1-positive some cells were similar to AE1-negative some cells during K?-R. LC3 protein expression increased significantly and autophagic vacuoles appeared particularly in PCs on days 14 of K?-D and in ICs on days 3 of K?-R. These results suggest that PCs and ICs may interconvert in response to changes in dietary K+ availability and that autophagic pathways may be involved in the interconversion.</P>

Expression of beta-catenin and its mechanism of delocalization in intestinal-type early gastric cancer based on mucin expression.

Lee, Soo Han,Kang, Hyun Jeong,Shin, Dong-Hun,Cho, Duk-Yeon,Song, Jin Mi,Lee, Han Cheol,Kim, Gwang Ha,Song, Geun Am,Sol, Mee Young,Kim, Jee Yeon,Choi, Kyung Un,Lee, Chang Hun,Huh, Gi Young,Park, Do You Gutenberg 2009 HISTOLOGY AND HISTOPATHOLOGY Vol.24 No.7

<P>The biological characteristics of intestinal-type early gastric cancers (ICs) differ based on mucin phenotypes. Beta-catenin delocalization is a predictive marker of aggressive biological behavior (submucosal invasion and lymph node metastasis) of ICs. The presumptive causative genetic alterations leading to delocalization of beta-catenin in ICs are still controversial, and there are only a few reports regarding beta-catenin expression in gastric cancer based on mucin phenotypes. Therefore, in the current study, the expression and mechanisms of delocalization of beta-catenin were elucidated on the basis of mucin phenotypes in 109 cases of ICs. There was increased cytoplasmic and nuclear beta-catenin expression (delocalization) in ICs with a predominant intestinal mucin phenotype (ICIP; 46.3% [25/54 cases]) compared to ICs with a predominant gastric mucin phenotype (ICGP; 20% [11/55 cases]). There were no beta-catenin or APC mutations in ICs. APC promoter hypermethylation was present in 49 of 105 (46.7%) cases of ICs. There was a significant relationship between APC promoter hypermethylation and beta-catenin delocalization in ICs, especially in ICIPs. There was no relationship between beta-catenin delocalization and APC gene loss of heterozygosity in ICs. In conclusion, we showed that beta-catenin delocalization was more evident in ICIPs, and APC promoter hypermethylation might play a role in delocalization of beta-catenin, especially in ICIPs.</P>

Developmental immunolocalization of heat shock protein 70 (HSP70) in epithelial cell of rat kidney.

Kang, S-S,Song, J-H,Lee, M-Y,Kang, Y-H,Lim, S S,Ryu, S-Y,Jung, J-Y Gutenberg 2011 Histology and histopathology Vol.26 No.11

<P>During renal development the cells in the medulla are exposed to elevated and variable interstitial osmolality. Heat shock protein 70 (HSP70) is a major molecular chaperone and plays an important role in the protection of cells in the renal medulla from high osmolality. The purpose of this study was to establish the time of immunolocalization and distribution of HSP70 in developing and adult rat kidney. In addition, changes in HSP70 immunolocalization following the infusion of furosemide were investigated. In adult animals, the HSP70 was expressed in the medullary thin ascending limb of Henle's loop (ATL) and inner medullary collecting duct (IMCD). In developing kidney, HSP70 immunoreactivity was first detected in the IMCD of the papillary tip on postnatal day 1. From four to 14 days of age, HSP70 was detected in the ATL after transformation from thick ascending limb, beginning at the papillary tip and ascending to the border between the outer and inner medulla. The immunolocalization of HSP70 in both the ATL and IMCD gradually increased during two weeks. The gradual increase in HSP70 was associated with an increase in its mRNA abundance. However, furosemide infusion resulted in significantly reduced HSP70 immunolocalization in the IMCD and ATL. These data demonstrated that the expression of HSP70 was closely correlated with changes in interstitial osmolality during the development of the kidney. We suggest that HSP70 protects ATL and IMCD cells in the inner medulla from the stress of high osmolality and may be involved in the transformation of the ATL of the long loop of Henle during renal development.</P>

Differential expression of Yes-associated protein and phosphorylated Yes-associated protein is correlated with expression of Ki-67 and phospho-ERK in colorectal adenocarcinoma.

Kim, Dong-Hoon,Kim, Seok-Hyung,Lee, Ok-Jun,Huang, Song-Mei,Kwon, Ju-Lee,Kim, Jin Man,Kim, Ji-Yeon,Seong, In Ock,Song, Kyu Sang,Kim, Kyung-Hee Gutenberg 2013 Histology and histopathology Vol.28 No.11

<P>Yes-associated protein (YAP) is a transcriptional co-activator and functions as a nuclear downstream effector of the Hippo pathway. Differential expression of YAP and phosphorylated Yes-associated protein (pYAP), which are involved in the expression of Ki-67 and phosphorylated extracellular signal-regulated kinase (pERK) in colorectal adenocarcinoma (CRAC), is not clear. Herein, we hypothesized that nuclear expression of YAP could predict cell proliferation and poor prognosis, while cytoplasmic expression of pYAP would show a reverse correlation with cell proliferation. Paraffin-embedded samples from 144 CRAC patients were studied using immunohistochemistry for YAP, pYAP, Ki-67 and pERK. Frozen samples from 20 CRAC patients were examined for YAP mRNA in tumor and non-tumor tissues, using quantitative real-time PCR. High nuclear YAP expression coincided with high Ki-67 expression (P=0.002). The high nuclear YAP expression group tended to display a poor overall and disease-free survival (P=0.089 and P=0.089, respectively), but YAP mRNA levels in the 20 CRAC tissues were not significantly different in comparison with the 20 non-tumor tissues (P=0.929). We observed an inverse correlation between high cytoplasmic pYAP expression and high Ki-67 expression (P=0.001). Nuclear pERK expression was positively correlated with nuclear YAP expression, but negatively correlated with cytoplasmic pYAP expression (P=0.017 and P=0.020, respectively). Activated nuclear YAP and inactivated cytoplasmic pYAP in CRAC showed a positive correlation with Ki-67 and nuclear pERK expression, suggesting that the expression of YAP and pYAP is a possible predictor of tumor cell proliferation and prognosis in CRAC.</P>

High MET copy number and MET overexpression: poor outcome in non-small cell lung cancer patients.

Park, Sanghui,Choi, Yoon-La,Sung, Chang Ok,An, Jungsuk,Seo, Jinwon,Ahn, Myung-Ju,Ahn, Jin Seok,Park, Keunchil,Shin, Young Kee,Erkin, Ozgur Cem,Song, Kyung,Kim, Jhingook,Shim, Young Mog,Han, Joungho Gutenberg 2012 Histology and histopathology Vol.27 No.2

<P>The aim of this study was to evaluate the prevalence and prognostic role of increased gene copy number and protein expression of MET and EGFR in non-small cell lung cancer (NSCLC) patients. Samples were collected from 380 patients with surgically resected NSCLC, and fluorescence in situ hybridisation (FISH) and immunohistochemistry (IHC) were performed. EGFR amplification and high polysomy (EGFR FISH-positive) were observed in 9.7% and 17.4% of the patients, respectively. EGFR was overexpressed (EGFR IHC-positive) in 19.2% of the patients. Neither EGFR FISH-positive nor EGFR IHC-positive status affected survival after resection. Increased MET copy number (MET FISH-positive by University of Colorado Cancer Center criteria) was observed in 11.1% of the patients (high polysomy, 8.7%; gene amplification, 2.4%). According to the Cappuzzo system, 7.1% of the patients were MET FISH-positive. MET FISH positivity was a negative prognostic factor, especially in patients with adenocarcinoma histology (p=0.040), female gender (p=0.010), old age (p=0.084), and EGFR FISH negativity (p=0.020) at the univariate level but not at the multivariate level. MET was overexpressed (MET IHC-positive) in 13.7% of the patients and associated with shorter overall and disease-free survival (p=0.010 and p=0.056, respectively). Multivariate analysis revealed that MET IHC-positive patients had a significantly increased risk of death (hazard ratio, 1.618; 95% confidence interval, 1.066-2.456; p=0.024). Increased MET copy number and MET overexpression are negative prognostic factors for surgically resected NSCLCs.</P>

Anti-death strategies against oxidative stress in grafted mesenchymal stem cells.

Chang, Woochul,Song, Byeong-Wook,Moon, Jae-Youn,Cha, Min-Ji,Ham, Onju,Lee, Se-Yeon,Choi, Eunmi,Choi, Eunhyun,Hwang, Ki-Chul Gutenberg 2013 Histology and histopathology Vol.28 No.12

<P>Mesenchymal stem cells (MSCs) possess the potential for use in cell-based therapy for repair of myocardial injury. The therapeutic potential of MSCs is based on the capacity of MSCs to differentiate into cardiac tissue and release paracrine factors. However, a major problem in the clinical application of MSC-based therapy is the poor viability of transplanted MSCs at the site of graft due to harsh microenvironment conditions, such as ischemia and/or anoikis. Ischemia after myocardial infarction (MI) and interaction of MSCs with their niche is associated with increased production of reactive oxygen species (ROS). ROS hinder cell adhesion and induce detachment of cells, which induces anoikis signals in implanted MSCs. Therefore, strategies to regulate oxidative stress following the implantation of MSCs are therapeutically attractive. In this review, we first describe ROS as a major obstacle in MSC-based therapy and focus on manipulation of implanted MSCs to reduce ROS-mediated anoikis.</P>

Neurobiological toxicity of radiation in hippocampal cells.

Kim, Joong-Sun,Yang, Miyoung,Kim, Sung-Ho,Shin, Taekyun,Moon, Changjong Gutenberg 2013 Histology and histopathology Vol.28 No.3

<P>Worldwide radiation exposure is increasing due to recent nuclear accidents, space travel, atomic weapons testing and use, and medical treatments. In adult animals, ionizing radiation can significantly impact hippocampal neurogenesis and negatively affect hippocampal functions such as cognition. However, there is considerable uncertainty regarding the mechanisms underlying these effects. This article reviews in vivo and in vitro studies on the effects of irradiation on hippocampal neurogenesis and function in order to gain new mechanistic insights. This information will provide complementary views of our understanding of the normal brain's tolerance to radiation exposure, the potentially serious implications of radiation exposure to cognition, and lead to a discussion of potential strategies for pharmacotherapy and behavioral intervention.</P>

Clinicopathologic characteristics of STAT1 positive/interleukin-8 negative subgroup in triple negative breast cancer defined by surrogate immunohistochemistry.

Kim, Sewha,Kim, Do Hee,Jung, Woo-Hee,Koo, Ja Seung Gutenberg 2013 Histology and histopathology Vol.28 No.11

<P>The aim of this study was to define immune-related triple negative breast cancer (TNBC) using immunohistochemistry for STAT1, CD20, CD3, IL-8, and IFN-γ and to assess its clinicopathologic characteristics.</P>

Identification of S100A8 and S100A9 as negative regulators for lymph node metastasis of gastric adenocarcinoma.

Choi, Jin Hwa,Shin, Na Ri,Moon, Hyun Jung,Kwon, Chae Hwa,Kim, Gwang Ha,Song, Geun Am,Jeon, Tae Yong,Kim, Dae Hwan,Kim, Dong Hun,Park, Do Youn Gutenberg 2012 HISTOLOGY AND HISTOPATHOLOGY Vol.27 No.11

<P>With increasing therapeutic use of minimally invasive therapy for treatment of early gastric cancer, prediction of lymph node metastasis is important. In search of tissue biomarkers for prediction of lymph node metastasis of gastric adenocarcinoma, we analyzed gastric adenocarcinoma tissue using proteomic methods. We have done 2D-PAGE and MALDI-TOF MS analysis in matched normal and gastric cancer tissues. We also evaluated the clinicopathological significance of expression of S100A8 and S100A9 in gastric adenocarcinoma using a tissue microarray of 218 gastric adenocarcinoma specimens. Cell invasion and migration assay were performed to confirm functional role of S100A8 and S100A9 using small hairpin RNA lentivirus. We identified 8 up-regulated and 5 down-regulated proteins in gastric cancer tissues compared to matched normal mucosa. Of these, expression of S100A8 and S100A9 occurred mainly in stromal cells and inflammatory cells between tumor cells. Correlation was observed between small lesion size, decreased depth of invasion, a tendency to absence of lymphovascular tumor emboli, a decrease in perineural invasion and lymph node metastasis, and expression of stromal S100A8. In addition, increased expression of stromal S100A9 in gastric adenocarcinoma was associated with small lesion size and a decrease in lymph node metastasis. Functional analysis confirmed that down-regulation of S100A8 and S100A9 by small hairpin RNA lentivirus induced an increase of migration and invasion in gastric cancer cell lines. Taken together, these findings suggest that S100A8 and S100A9 are negative regulators of lymph node metastasis of gastric adenocarcinoma and can be used as biomarkers for prediction of lymph node metastasis in gastric adenocarcinoma.</P>

The pivotal role of PDGF and its receptor isoforms in adipose-derived stem cells.

Kim, Won-Serk,Park, Hyung-Sook,Sung, Jong-Hyuk Gutenberg 2015 Histology and histopathology Vol.30 No.7

<P>Platelet-derived growth factor (PDGF) is one of the growth factors that reportedly regulates cell growth and division of mesenchymal cells. Although PDGF isoforms and their receptors reportedly play a pivotal role in mesenchymal stem cell regulation, there is a paucity of literature reviewing the role of PDGF in adipose-derived stem cells (ASCs). Therefore, we summarized previous reports on the expression and functional roles of PDGF and its receptor isoforms in this review. In addition, we examined findings pertaining to underlying molecular mechanisms and signaling pathways with special focus on PDGF-D/PDGFRβ. ASCs only express PDGF-A, -C, -D, PDGFRα, and PDGFRβ. PDGFRα expression decreases with adipocyte lineage, while PDGFRβ inhibits white adipocyte differentiation. In addition, PDGFRβ induces proliferation, migration, and angiogenesis and up-regulates the expression of paracrine factors in ASCs. Although PDGF-B and -D mediate their functions mainly by PDGFRβ and ROS generation, there are many differences between them in terms of regulating ASCs. PDGF-D is endogenous, generates ROS via the mitochondrial electron transport system, and regulates the autocrine loop of ASCs in vivo. Furthermore, PDGF-D has stronger mitogenic effects than PDGF-B.</P>