• Journal of Korean Physical Therapy Science
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• v.10 no.1
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• pp.198-205
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• 2003

We evaluated the effect of low power GaAsAl laser on re-epithelization in full-thickness excisional wound of rat skin. Two full-thickness excisions were made on the back of the experimental animals. Low power laser applications with 10mW intensity were treated experimental animals twice a day for 7 days. On the seventh postoperative day the quantitative analysis of re-epithelization was performed using immunohistochemical staining for proliferating cell nuclear antigen (PCNA). The majority of PCNA immunoreactive cells was observed at epithelial cells in the margin of full thickness excisional wound. The low power laser treatments significantly increased the number of PCNA immunoreactive cell as compared to that of non treated animal group (p<0.01). The shape of PCNA immunoreactive cell appeared as small dark, round to ovoid structures. Most PCNA immunoreactive cells exhibited a high intensity of staining that contrasted sharply with the surrounding background. In conclusion, these findings suggest that GaAlAs laser treatments effectively enhance the epithelial wound healing by the stimulating cell proliferation. Furthermore, the majority of cell proliferation occurred in the margin of full thickness excisional wound.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.958-963
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• 2006

The effect of ginsenosides (GS) on germ cell proliferation was evaluated with a chicken ovarian germ-somatic cell coculture model and the mechanism involving protein kinase C (PKC) pathway was investigated. Ovarian cells were cultured in serum-free McCoy's 5A medium and challenged with GS alone or in combinations with PKC activator (phorbol 12-myristate 13-acetate, PMA) or inhibitor ($H_7$) for 48 h. The number of germ cells was counted and the proliferating cells were identified by immunocytochemistry of proliferating cell nuclear antigen (PCNA). Results showed that GS significantly increased germ cell proliferation and this stimulating effect was further increased by PMA, but inhibited by H7, in a dose-dependent manner. Moreover, GS-elevated PCNA expression and the PCNA -labeling index of germ cells displayed similar changes with the increased numbers of germ cells. These results indicated that GS stimulated proliferation of ovarian germ cells with involvement of the PKC-mediated system.

• Biomedical Science Letters
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• v.13 no.3
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• pp.239-244
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• 2007

Hoxc8 is one of the homeotic developmental control genes regulating the expression of many downstream target genes, through which animal body pattern is established during embryonic development. In previous proteomics analysis, proliferating cell nuclear antigen (PCNA) which is also known as cyclin, has been implied to be regulated by Hoxc8 in F9 murine embryonic teratocarcinoma cell. When the 5' upstream region of PCNA was analyzed, it turned out to contain 20 Hox core binding sites (ATTA) in about 1.17 kbp (kilo base pairs) region ($-520{\sim}-1690$). In order to test whether this region is responsible for Hoxc8 regulation, the upstream 2.3 kbp fragment of PCNA was amplified through PCR and then cloned into the pGL3 basic vector containing a luciferase gene as a reporter. When the luciferase activity was measured in the presence of effector plasmid (pcDNA : c8) expressing murine Hoxc8, the PCNA promoter driven reporter activity was reduced. To confirm whether this reduction is due to the Hoxc8 protein, the siRNA against Hoxc8 (5'-GUA UCA GAC CUU GGA ACU A-3' and 5'-UAG UUC CAA GGU CUG AUA C-3') was prepared. Interestingly enough, siRNA treatment up regulated the luciferase activity which was down regulated by Hoxc8, indicating that Hoxc8 indeed regulates the expression of PCNA, in particular, down regulation in NIN3T3 cells. These results altogether indicate that Hoxc8 might orchestrate the pattern formation by regulating PCNA which is one of the important proteins involved in several processes such as DNA replication and methylation, chromatin remodeling, cell cycle regulation, differentiation, as well as programmed cell death.

• Korean Journal of Bronchoesophagology
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• v.7 no.2
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• pp.152-160
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• 2001

The presence of HPV DNA and the expression of p53 protein and proliferating cell nuclear antigen(PCNA) in head and neck squamous cell carcinoma were determined to evaluate the relationship of these factors and their association with their pathologic stages and cervical lymph node metastasis. Among 65 patients the presence of HPV DNA was found in 12 cases(18.5%), p53 was found positive in 32 cases(49.2%) and expression of PCNA was observed in 24 cases(36.9%). The expression of PCNA was more frequent in the HPV positive cancers compared with the HPV negative ones(p =0.0018), and p53 revealed its higher rate of cooccurrence with the expression of PCNA(p =0.008), which might suggest that PCNA expression has a positive relationship with HPV and p53 mutation in head and neck cancer. There might be inverse relationship between HPV and p53 mutation(p =0.063), but 3 cases showed both HPV DNA positivity and p53 expression. HPV was detected at a higher rate in the early pathologic stages than in the advanced stages of cancer, and p53 expression was more frequently found in the advanced stages(p =0.044). These results suggests that HPV and p53 mutation might have different etiologic roles in the development of head and neck cancer, or cases with p53 mutation might have more aggressive behavior. PCNA expression showed no difference between early and late stages of cancer, and between cases with and without cervical lymph node metastasis.

• Journal of Korean Neurosurgical Society
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• v.30 no.7
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• pp.861-869
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• 2001

Objective : In this study, we investigated the relationship between the histologic grading of meningiomas and proliferative potentials determined by the Ki-67, proliferating cell nuclear antigen(PCNA) and flow cytometry (FCM) with the aim of determining whether these potentials can be used as a parameter to the proliferative activity, in particular of atypical and malignant meningiomas. Methods : This study consisted of 47 meningiomas(6 malignant, 14 atypical, and random sampled 27 benign meningiomas). By immunohistochemical staining of Ki-67 and PCNA on formalin-fixed, paraffin-embedded sections, the anti-human rabbit polyclonal antibody against Ki-67 antigen and anti-PCNA monoclonal antibody(PC10) scores were counted. FCM was also performed on paraffin-embedded tissue using a selective staining technique for DNA. DNA ploidy, S-phase fraction, and proliferative index(PI)) were determined. Results : The results are summarized as follows ; 1) Proliferation rates as assessed by Ki-67 and PCNA closely correlated with the degree of anaplastic histologic features. 2) Proliferative potentials determined by FCM(S-phase fraction and PI) were not able to distinguish between benign and atypical/malignant meningiomas. 3) DNA ploidy was not a useful indicator of histologic grade in these tumors. 4) Proliferative potentials such as Ki-67 staining index(SI) and PCNA SI did not correlate with the ploidy pattern. 5) There was a linear correlation between Ki-67 SI and PCNA SI, but we could not find a correlation between Ki-67 SI and S-phase fraction or PI. Our results also did not show a statistically signficant correlation between PCNA SI and S-phse fraction or PI. Conclusions : We conclude that evaluation of the proliferative potentials with Ki-67 and PCNA is important as an additional factor for the prediction of malignancy in meningiomas. A dual study of Ki-67 and PCNA SIs on the same tissue might improve the accuracy with which the proliferative potential of a tumor can be predicted. We demonstrated that FCM in meningiomas is not valuable in predicting the behavior of these neoplasms, but we did observe a trend toward more malignancy with higher percent S-phase fraction and higher PI. Analysis of the S-phase fraction and PI might therefore be a useful tool to discriminate among histologic grades of meningiomas.

• Korean Journal of Veterinary Research
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• v.37 no.2
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• pp.281-289
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• 1997

The study was designed to investigate the effects of progesterone and estrogen on the uterus of rats by immunohistochemical methods using Proliferating Cell Nuclear Antigen (PCNA) antibody. Eighteen female rats(Wistar), weighing initially about 300g, were ovariectomized. These rats were divided into four groups, progesterone-treated group, estrogen-treated group, estrogen+progesterone-treated group, and control group, progesterone-treated group was injected with 1mg of progesterone per rat per day for 2 days and estrogen-treated group with $20{\mu}g$ of $17{\beta}-estradiol$ for 3 days and estrogen+progesterone-treated group with $17{\beta}-estrdiol$ for 3 days and then with progesterone for 2 days as above. In gross findings, the uteri were markedly hypertrophied by estrogen treatment but were not affect in size by progesterone treatment. Immunohistochemical investigation was performed on the cell types with higher appearance of PCNA positive reaction cells in four groups. The groups with higher appearance of the stromal cells were ordered as estrogen-treated group, progesterone-treated group, estrogen+progesterone-treated group, and control group. The muscle cells were ordered as progesterone-treated group, estrogen-treated group, estrogen+progesterone-treated group, and control group. Positive reaction cells of the stromal cells were total 4.6 times higher than those of muscle cells. Therefore, the affect of the hypertrophy on the uterus by estrogen was larger than those of progesterone and affect on the uterus by stromal cells were larger than those of muscle cells. The group with more PCNA positive reaction cells of luminal epithelial cells were ordered as control group, progesterone-treated group, estrogen+progesterone-treated group, and estrogen-treated group, and glandular epithelial cells were ordered as estrogen+progesterone-treated group, progesterone-treated group, control group, and estrogen-treated group. It was suggested that estrogen and progesterone did not affect on the proliferating cells of luminal epithelial cells and affection of progesterone on the development of glandular epithelial cell was larger than that of estrogen.

• Journal of Microbiology and Biotechnology
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• v.26 no.4
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• pp.637-647
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• 2016

Proliferating cell nuclear antigen (PCNA) is a critical eukaryotic replication accessory factor that supports DNA binding in DNA processing, such as DNA replication, repair, and recombination. PCNA consists of three toroidal-shaped monomers that encircle double-stranded DNA. The diverse functions of PCNA may be regulated by its interactions with partner proteins. Many of the PCNA partner proteins generally have a conserved PCNA-interacting peptide (PIP) motif, located at the N- or C- terminal region. The PIP motif forms a 3₁₀ helix that enters into the hydrophobic groove produced by an interdomain-connecting loop, a central loop, and a C-terminal tail in the PCNA. Post-translational modification of PCNA also plays a critical role in regulation of its function and binding partner proteins. Structural and biochemical studies of PCNA-protein will be useful in designing therapeutic agents, as well as estimating the outcome of anticancer drug development. This review summarizes the characterization of eukaryotic PCNA in relation to the protein structures, functions, and modifications, and interaction with proteins.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.3627-3630
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• 2012

The epithelial cell adhesion molecule (EpCAM) is a pan-epithelial differentiation antigen that is expressed on almost all carcinomas. However, a role in rat liver carcinogenesis has never been reported previously. Thus, its expression was investigated herein in rat liver tumors induced by diethylnitrosamine (DEN). Twenty male 5-week-old F344 rats were used in this experiment. Mini-osmotic pumps containing doses of 47.5 mg of DEN were inserted into the abdominal cavity of each animal to initiate liver carcinogenesis. All animals were sacrificed at 26 weeks after DEN treatment. At necropsy, hepatic masses were processed for histopathological examination, which revealed forty-four hepatocellular adenomas (HCAs) and twenty hepatocellular carcinomas (HCC). Tumors were immunohistochemically analyzed for EpCAM, proliferating cell nuclear antigen (PCNA) and co-localization of the two. EpCAM expression was mainly detected in hepatic tumor cells, showing a cytoplasmic staining pattern. However, expression was also slightly observed in normally-appearing surrounding hepatic cells. PCNA expression was highly detected in tumor cells, showing nuclear staining. Double staining of EpCAM and PCNA in tumors showed many cells with co-localization. Taken together, EpCAM and PCNA expression were increased in DEN-induced tumors and many tumor cells showed co-expression. It is suggested that EpCAM may increase during DEN-induced tumors, possibly associated with cell proliferation.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.2
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• pp.85-99
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• 2004

Purpose: This study observed the changes in the telomerase activity, it's developmental regulation, PCNA expression, and their correlation in rat's upper digestive organs during growth and aging. Materials and Methods: Upper digestive organs(buccal mucosa, gingiva, palate, submandibular and parotid glands, and tongue) were aseptically removed from Sprague-Dawley rats of fetal(gestational 20 days), growing(1, 2, 3, 5, and 7 weeks after birth) and adult(12 week old). Samples for telomerase activity were frozen on liquid nitrogen immediately after sacrifice, and stored until the use at $-75^{\circ}C$ in order to measure it. Telomerase activity was measured by a PCR-based telomeric repeat amplication protoco(TRAP) assay and quantitated with Photometric Telo TAGGG Telomerase PCR ELISA plus(Roche Diagnostics GmbH. Mannheim. Germany). PCNA expression were measured immunohistochemistry with anti PCNA Ab-1, Clone PC10(NeoMark. California. USA). Results: 1. Telomerase activities in buccal mucosa, palate and gingiva were the highest in fetus and decreased gradually or rapidly after birth and then diminished, but In salivary gland and tongue were the highest in fetus and also high at 1 week and then decreased rapidly. 2. PCNA expression in buccal mucosa, gingiva, Tongue and salivary gland was the highest in fetus and decreased gradually and then diminished. but only in palate decreased rapidly after birth and then diminished. Conclusion: The highest telomerase activity of embryonic stage decreased rapidly after birth in rat's upper digestive organs. There may be a developmental regulation of telomerase activity, but not a tissue-specific. This telomerase activity seems correlated closely with PCNA expression in rat's upper digestive system.

• Applied Microscopy
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• v.42 no.3
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• pp.115-123
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• 2012

Human placenta extract (hPE) has therapeutic potential against certain diseases such as burn injury, liver cirrhosis and chronic wound through stimulating tissue repair processes. However, the effects of hPE on liver regeneration in animals are unknown. This study investigated the effect of hPE on the expression of proliferating cell nuclear antigen (PCNA) during liver regeneration induced by partial hepatectomy (PH) in rats. The activities of AST, ALT and ALP increased during a few days after PH. A high level of ALP was particularly seen at day 3 in the control group. All the levels of experimental groups were normalized by day 5 after PH. On immunohistochemistry, the expression of PCNA increased at the early days, showed a peak at day 3 after PH. The PCNA staining was more obvious in the experimental group over the whole period. By western blotting, PCNA seemed to be more strongly expressed in the hPE injected group in the early stage and fell to almost undetectable levels at day 7. On immunocytochemical observations, the number of PCNA-gold particles in the nuclei at day 1 of the hPE treated groups was more than those of the untreated groups. The results suggest that hPE could accelerate liver regeneration induced by PH involving the expression of PCNA in rats.