• Journal of Oral Medicine and Pain
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• v.24 no.2
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• pp.145-161
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• 1999

The proto-oncogene bcl-2 confers a survival advantage to cells by blocking programmed cell death (apoptosis). Overexpression of bcl-2 probably plays a role in tumorigenesis, and the expression of the bcl-2 protein has been investigated in many kinds of tumors. An increased expression of nitric oxide synthetase(NOS) has been observed in human colon cancer cell lines as well as in human gynecological, breast, and CNS tumors. However there have been only a few reports on the expression of bcl-2 and $NOS_2$ in oral white lesions and cancer. The aim of this study was to investigate the relationship between the expression of Bcl-2 and $NOS_2$ and several pathological parameters such as histological types and layers. We reported desregulation of bcl-2 and $NOS_2$ expression during progression from oral white lesion, lichen planus and leukoplakia to squamous cell carcinoma. The obtained results were as follows: 1. Immunohistochemical analysis with monoclonal antibodies to bcl-2 oncoprotein and $NOS_2$ in formalin-fixed paraffin-embedded tissue sections revealed that bcl-2 expression is restricted to the basal cell layer and $NOS_2$ was mild expressed only in subepithelial inflammatory cells in normal human mucosa. There wasn't specific finding of those in lichen planus and leukoplakia. 2. Bcl-2 immunoreactivity in severe epithelial dysplasia or CIS occurs throughout the epithelium, $NOS_2$ reactivity in most superficial layer were noted. 3. In well-differentiated squamous cell carcinomas, mostly bcl-2 was overexpressed. In moderated and poor squamous cell carcinomas, the expression of $NOS_2$ was increased and that of bcl-2 was decreased. 4. The immunoreactivity of bcl-2 was 12.5% of normal mucosa, 30% of leukoplakia, 44% of lichen planus and 67% of carcinoma in situ. In carcinoma, those were 43%, 50% and 67% according to differentiation, respectively. 5. The immunoreactivity of $NOS_2$ was 25% of normal mucosa, 70% of leukoplakia, 78% of lichen planus and 100% of carcinoma in situ and epithelial dysplasia. In carcinoma, those were higher in moderated(100%) and poor(83%) squamous cell carcinomas than in well differentiated type(71%). 6. The expression of bcl-2 and $NOS_2$ by Western blot was increased highly in lichen planus and leukoplakia. Therefore, the expression of bcl-2 was increased in the white and precancerous lesions and that was decreased by differentiation of carcinoma. However, $NOS_2$ immunoreactivity in carcinoma in situ was lower than those in moderated and poor squamous cell. These findings suggest that the interaction of bcl-2 and $NOS_2$ may be roled importantly in growth and development of carcinoma.

• The Journal of Korean Society of Virology
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• v.28 no.3
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• pp.267-274
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• 1998

Human cytomegalovirus (HCMV) has the ability to activate the expression of many viral and cellular genes. Among various viral proteins, the immediate early proteins (IE1-72kDa, IE2-86kDa) have been known to be potent transactivators. The product of c-jun proto-oncogene is important in cell activation and differentiation. Here, we tried to find out if the IE could activate the c-jun promoter and also tried to identify the responsible sequence elements in the c-jun activation by IE1-72kDa. We found HCMV IE expression transactivated the c-jun promoter in human embryonal lung fibroblasts (HEL). The activation fold by IE1-72kDa, IE2-86kDa and IE2-55kDa was 23, 35, and 5, respectively. When the expression of each IE was combined, it showed synergism. Expression of (IE1-72kDa + IE2-86kDa) and (IE1-72kDa + IE2-86kDa + IE2-55kDa) resulted in 131 and 162 fold increase, respectively. The c-jun promoter region between -117 and -59 contains binding sites for the transcription factors Spl, CAAT, AP-l like (ATF/CREB), and MEF2. Transient expression assays were performed using various reporter plasmids containing the c-jun promoter-regulatory region linked to the luciferase gene and a plasmid expressing HCMV IE1 gene. Deletional and point mutational analysis showed that the sequence between -225 to -160 and the CTF binding site were involved in the up-regulation of c-jun promoter.

• Animal Bioscience
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• v.34 no.4
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• pp.546-557
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• 2021

Objective: If fertilization does not occur within a specific period, the quality of unfertilized oocytes in the oviduct (in vivo aging) or in culture (in vitro aging) will deteriorate over time. Icariin (ICA), found in all species of Epimedium herbs, has strong antioxidant activity, and is thought to exert anti-aging effects in vitro. We asked whether ICA protects oocytes against age-related changes in vitro. Methods: We analyzed the reactive oxygen species (ROS) levels and expression of antioxidant, maternal, and estrogen receptor genes, and along with spindle morphology, and the developmental competence and quality of embryos in the presence and absence of ICA. Results: Treatment with 5 μM ICA (ICA-5) led to a significant reduction in ROS activity, but increased mRNA expression of glutathione and antioxidant genes (superoxide dismutase 1 [SOD1], SOD2, peroxiredoxin 5, and nuclear factor erythroid 2-like 2), during aging in vitro. In addition, ICA-5 prevented defects in spindle formation and chromosomal alignment, and increased mRNA expression of cytoplasmic maturation factor genes (bone morphogenetic protein 15, cyclin B1, MOS proto-oncogene, serine/threonine kinase, and growth differentiation factor-9). It also prevented apoptosis, increased mRNA expression of antiapoptotic genes (BCL2-like 1 and baculoviral IAP repeat-containing 5), and reduced mRNA expression of pro-apoptotic genes (BCL2 antagonist/killer 1 and activation of caspase-3). Although the maturation and cleavage rates were similar in all groups, the total cell number per blastocyst and the percentage of apoptotic cells at the blastocyst stage were higher and lower, respectively, in the control and ICA-5 groups than in the aging group. Conclusion: ICA protects oocytes against damage during aging in vitro; therefore, it can be used to improve assisted reproductive technologies.

• Biomolecules & Therapeutics
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• v.30 no.4
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• pp.340-347
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• 2022

Advanced or metastatic breast cancer affects multiple organs and is a leading cause of cancer-related death. Cancer metastasis is associated with epithelial-mesenchymal metastasis (EMT). However, the specific signals that induce and regulate EMT in carcinoma cells remain unclear. PRR16/Largen is a cell size regulator that is independent of mTOR and Hippo signalling pathways. However, little is known about the role PRR16 plays in the EMT process. We found that the expression of PRR16 was increased in mesenchymal breast cancer cell lines. PRR16 overexpression induced EMT in MCF7 breast cancer cells and enhances migration and invasion. To determine how PRR16 induces EMT, the binding proteins for PRR16 were screened, revealing that PRR16 binds to Abl interactor 2 (ABI2). We then investigated whether ABI2 is involved in EMT. Gene silencing of ABI2 induces EMT, leading to enhanced migration and invasion. ABI2 is a gene that codes for a protein that interacts with ABL proto-oncogene 1 (ABL1) kinase. Therefore, we investigated whether the change in ABI2 expression affected the activation of ABL1 kinase. The knockdown of ABI2 and PRR16 overexpression increased the phosphorylation of Y412 in ABL1 kinase. Our results suggest that PRR16 may be involved in EMT by binding to ABI2 and interfering with its inhibition of ABL1 kinase. This indicates that ABL1 kinase inhibitors may be potential therapeutic agents for the treatment of PRR16-related breast cancer.

• Animal Bioscience
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• v.36 no.7
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• pp.1022-1033
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• 2023

Objective: p66Shc, a 66 kDa protein isoform encoded by the proto-oncogene SHC, is an essential intracellular redox homeostasis regulatory enzyme that is involved in the regulation of cellular oxidative stress, apoptosis induction and the occurrence of multiple age-related diseases. This study investigated the expression profile and functional characteristics of p66Shc during preimplantation embryo development in sheep. Methods: The expression pattern of p66Shc during preimplantation embryo development in sheep at the mRNA and protein levels were studied by quantitative real-time polymerase chain reaction (RT-qPCR) and immunofluorescence staining. The effect of p66Shc knockdown on the developmental potential were evaluated by cleavage rate, morula rate and blastocyst rate. The effect of p66Shc deficiency on reactive oxygen species (ROS) production, DNA oxidative damage and the expression of antioxidant enzymes (e.g., catalase and manganese superoxide dismutase [MnSOD]) were also investigated by immunofluorescence staining. Results: Our results showed that p66Shc mRNA and protein were expressed in all stages of sheep early embryos and that p66Shc mRNA was significantly downregulated in the 4-to 8-cell stage (p<0.05) and significantly upregulated in the morula and blastocyst stages after embryonic genome activation (EGA) (p<0.05). Immunofluorescence staining showed that the p66Shc protein was mainly located in the peripheral region of the blastomere cytoplasm at different stages of preimplantation embryonic development. Notably, serine (Ser36)-phosphorylated p66Shc localized only in the cytoplasm during the 2- to 8-cell stage prior to EGA, while phosphorylated (Ser36) p66Shc localized not only in the cytoplasm but also predominantly in the nucleus after EGA. RNAi-mediated silencing of p66Shc via microinjection of p66Shc siRNA into sheep zygotes resulted in significant decreases in p66Shc mRNA and protein levels (p<0.05). Knockdown of p66Shc resulted in significant declines in the levels of intracellular ROS (p<0.05) and the DNA damage marker 8-hydroxy2'-deoxyguanosine (p<0.05), markedly increased MnSOD levels (p<0.05) and resulted in a tendency to develop to the morula stage. Conclusion: These results indicate that p66Shc is involved in the metabolic regulation of ROS production and DNA oxidative damage during sheep early embryonic development.

• Journal of Life Science
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• v.26 no.1
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• pp.101-108
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• 2016

The aim of this study was to evaluate the relationships between the expression of Heat shock protein70 (HSP70), Raf-1 and Bcl-2-associated athanogene-1 (BAG1) protein in diffuse type gastric carcinoma and examine association of HSP70, Raf-1 and BAG1 expression with various clinic-pathological factors and survival. Heat shock protein70 is induced in the cells in response to various stress conditions, including carcinogens. Overexpression of heat shock protein 70 has been observed in many types of cancer. The proto-oncoprotein Raf is pivotal for mitogen-activated protein kinase (MAPK) signaling, and its aberrant activation has been implicated in multiple human cancers. Overexpression of BAG1 protein has been documented in some type of human cancer. BAG1 has been reported to interact with protein involved with a variety of signal pathway, and regulation of cell differentiation, survival and apoptosis. These interaction partners include HSP70 and Raf-1. The percentage of tumors exhibiting HSP70 positivity was significantly in cases of positive lymph node metastasis (64.9%) compared to cases without lymph node metastasis (35.1%, p=0.007). HS70 expression was correlated with pathological N-stage (p=0.006). Expression of BAG1 was detected in the majority of diffuse type gastric carcinoma tissues (71.7%), especially in younger patients (80% vs 52.6%, p=0.035). Furthermore BAG1 expression was correlated with tumor size (p=0.020). Raf-1 expression was found to be significantly associated with tumor size (p=0.005). The result indicate that HSP70 was significantly correlated the progression of diffuse type gastric cancer. Expression of BAG1 and Raf-1 may be used as diagnostic markers for gastric carcinoma.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 1997.06b
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• pp.8-10
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• 1997

종양은 아직 그 발생 원인과 기작이 정확히 밝혀져 있지 않으므로 정확한 정의를 내리는 것은 어려우나 일반적으로 종양이란 정상 세포가 갖고 있는 세포 분열의 특이성을 상실하여 일어나는 조직의 자율적인 과잉 성장을 말한다. 이와 같은 세포의 비정상적인 증식에 의한 종양을 임상 및 병리 형태학적으로 양서 종양과 악성종양으로 분류한다. 양성 종양을 일으키는 종양 세포는 정상 세포와 비슷할 뿐 아니라 그 주변 세포들과 확실한 경계를 이루고 있으며 증식도 느리며 다른 부위로의 전이가 없다. 이에 반해 악성종양은 일반적으로 증식도 빠르고 이형의 세포로서 주변의 조직으로 확산, 전이될 뿐만 아니라 최종적으로 숙주인 개체를 사망시킨다. 악성종양은 다시 상피 조직에서 유례한 암, 비상피 조직에서 유래된 육종, 백혈구에서 유래된 백혈병 등으로 구별하지만 그의 본질은 거의 같으며 모든 악성종양은 통속적으로 암이라고 불리운다. 종양의 발생원인으로 크게 3가지로 나눌 수 있는데 화학물질, 바이러스 및 유전적 요인에 의한 것으로 알려졌다. 최초의 발암물질로 알려진 benzopyrene에 의한 발암 등 연구에 의해 화학적 발암원들은 직접 발암 물질로 작용하는 것이 아니라, 일단 체내에서 대사된 후 이들 대사 산물일 DNA 등에 작용함으로써 발암이 유도 되는 것으로 밝혀졌다. 이와 같이 화학적 변화를 거친 후에야 DNA에 영향을 미치는 것외에 다른 화학물질들은 또 다른 기작을 통해 암을 유발하는데 쥐의 피부에 benzopyrene을 한 번 처리하면 암을 유발하지 않으나 여기에 phorbol ester를 처리하면 높은 빈도로 암이 형성된다. 여기서 benzopyrene과 같이 세포의 DNA에 돌연변이를 일으키는 작용을 하는 발암물질을 발암개시제라 하고 phorbol ester처럼 그 자체로는 발암능이 없으나 발암개시제에 노출된 세포에 영향을 미쳐 발암능을 크게 강화시켜 주는 것을 발암촉진제라고 한다. 암은 세포증식 제어계에 DNA가 이상을 일으킨 현상을 말하는 데 이와 같은 DNA의 변형된 유전정보에 의해 암과 관련된 단백질을 합성하므로 이 DNA를 암유전자라 부르며 바이러스에서 유래된 것을 V-one 그리고 세포에서 유래된 것을 c-one이라 한다. 암유전자는 본래 암을 형성하기 위한 것이 아니라 증식제어 유전자로서 변이나 비정상으로 활성화 됨으로써 암을 유발시키므로 proto-oncogene이라 부른다. 또한 고등동물의 유전자 중에는 세포성장을 억제하는 유전자들이 있으며 이들은 세포의 성장 생존 분화를 조절하는 것으로 생각되고 있다. 따라서 이들 유전자는 세포의 암변형을 억제하는 기능을 가지고 있다. 이들 유전자의 이상으로 세포성장 억제기능이 상실되면 세포의 과잉 성장이 초래되면 결과적으로 암으로 유발하는 것으로 추측되고 있다. 최근의 연구에 의하면 암세포에서 암억제 유전자의 이상과 암유전자의 활성화가 함께 발견 되면서 정상세포가 암으로 변형되는 과정에는 암억제 유전자의 이상과 암유전자의 활성화가 동시에 관여한 가능성이 높은 것으로 알려져 있다. 정상 세포가 암을 유발하기 위해서는 발암의 다단계설에서와 같이 여러 단계의 변과가 필요한데 여러 가지 요인에 의해 정상세포의 염색체가 변화되어 정상세포들이 가지고 있는 세포분열의 특이성을 상실하고 증식이 빠르고 저항력이 강한 세포가 선택 되어지고 비정상 서ㅔ포으 과잉 분여러에 의해 종양이 형성되며 이어서 혈관의 신생을 촉진하는 맥관형성, 전이 등이 과정을 거쳐 신체의 다른 부위로 전이된다. 20세기 초까지는 암은 노화와 함께 자연발생적으로 일어나는 피할 수 없는 질병으로 여겨졌으며 그 치료도 조기에 발견된 암환자에게 외과적인 치료를 하는 것이 최선의 방법 이었다. 그러나 현재에는 암환자의 80% 이상이 환경적 요인에 의해 암이 발생 된다고 믿어지고 있다. 과거 치료에 중점을 둔 것에서 점차 예방의 가능성과 그 방법의 모색에 관심을 갖게 되었으며 치료적인 면에서도 외과적 수술 이외에 방사선 치료, 항암제의 투여 등 약물요법, 면역요법의 이용 이외에 더 나아가 gene theraph 및 tumor vaccines 개발에 대한 관심도 증가되고 있다. 국제암연구협회에서는 인간에게 발암이 가능한 물질의 종류를 정기적으로 발표하고 있는데 지금까지 발암 가능성이 높다고 널리 알려진 위험요인을 크게 나누어 보면 다음과 같다. 흡연, 음주, 식이요인, 호르몬 및 기타 요인으로 약물, 자외선 등을 들 수 있는데 현재까지 이들 요인에 의한 발암 기작이 완전히 규명된 것은 아니지만 이들에 의한 발암의 확률이 높다는 것은 사실이므로 이 위험요인에 노출되는 것을 방지함으로써 암발생을 예방할 수 있을 것이다. 암발생의 예방법으로는 암발생 자체를 예방하는 것과 이미 발생한 암환자를 조기 발견하고 치료하는 방법이 있을 수 있다. 현재까지의 여러 연구 결과들을 보면 유전적인 요인을 제외한 대부분의 발암 위험인자들은 개개인의 생활습관과 밀접히 관련되어 있음을 알 수 있다. 이를 바탕으로 1992년 대한 암협회에서는 '암 예방 14개 권장 사항'을 발표하여 국민 홍보활동을 하고 있는데 그 내용의 반 이상이 식생활 습관과 관련되어 있을 정도이므로 암예방에 있어서의 식품의 역할이 매우 크다 할 수 있다. 따라서 건전한 생활습관과 더불어 적절한 식품의 섭취는 암예방을 위한 기본이 될 것이다.

• Science of Emotion and Sensibility
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• v.10 no.3
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• pp.411-418
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• 2007

Exposure to low frequency noise(LFN) can lead to vibroacoustic diseases(VADs), which include a systemic disease with lesions in a broad spectrum of organs and a psychiatric condition. It is known that VAD is an established risk factor for the development of many psychological conditions in humans and rodents, including major depression and anxiety disorder. The present study investigated the effects of LFN on neuronal stress responses in the rat brain. The neuronal expression of the proto-oncogene c-fos in the paraventricular nucleus(PVN) of the hypothalamus and tyrosine hydroxylase(TH) in the LC was observed. The immunocytochemical detection of the Fos protein and TH has been used as a marker of neuronal activation in response to stress. In addition, corticosterone concentration was evaluated by using an enzyme-linked immunosorbent assay(ELISA). The LFN groups were exposed to 32.5Hz and 125Hz of noise(4hr/day for 2days). The numbers of c-fos and TH-immunoreactive cells in the PVN and LC were significantly increased in the LFN groups(32.5Hz and 125Hz) compared to the normal group. Corticosterone concentration in plasma was also increased in LFN groups. The present results demonstrated that exposure with LFN produced a pronounced increase in expression of c-Fos and TH in stress-relevant brain areas. These results suggest that the neural characteristics involved in LFN are similar to those activated by typical processive stressors. These results also suggest that the central and peripheral activations by LFN may be related to LFN-related negative behavioral dysfunctions such as VADs.

• Toxicological Research
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• v.8 no.2
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• pp.343-357
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• 1992

Tumor necrosis factor-${\alpha}$(TNF), a polypeptide hormone secreted primarily by activated macrophages, was originally identified on the basis of its ability to cause hemorrhagic necrosis and tumor regression in vivo. Subsequently, TNF has been shown to be an important component of the host responses to infection and cancer and may mediate the wasting syndrome known as cachexia. These systemic actions of TNF are reflected in its diverse effects on target cells in vitro. TNF initiates its diverse cellular actions by binding to specific cell surface receptors. Although TNF receptors have been identified on most of animal cells, regulation of these receptors and the mechanisms which transduce TNF receptor binding into cellular responses are not well understood. Therefore, in the present study, the mechanisms how TNF receptors are being regulated and how TNF receptor binding is being transduced into cellular responses were investigated in rat liver plasma membranes (PM) and ME-180 human cervical carcinoma cell lines. $^{125}I$-TNF bound to high ($K_d=1.51{\pm}0.35nM$)affinity receptors in rat liver PM. Solubilization of PM with 1% Triton X-100 increased both high affinity (from $0.33{\pm}0.04\;to\;1.67{\pm}0.05$ pmoles/mg protein) and low affinity (from $1.92{\pm}0.16\;to\;7.57{\pm}0.50$ pmoles/mg protein) TNF binding without affecting the affinities for TNF, suggesting the presence of a large latent pool of TNF receptors. Affinity labeling of receptors whether from PM or solubilized PM resulted in cross-linking of $^{125}I$-TNF into $M_r$ 130 kDa, 90 kDa and 66kDa complexes. Thus, the properties of the latent TNF receptors were similar to those initially accessible to TNF. To determine if exposure of latent receptors is regulated by TNF, $^{125}I$-TNF binding to control and TNF-pretreated membranes were assayed. Specific binding was increased by pretreatment with TNF (P<0.05), demonstrating that hepatic PM contains latent TNF receptors whose exposure is promoted by TNF. Homologous up-regulation of TNF receptors may, in part, be responsible for sustained hepatic responsiveness during chronic exposure to TNF. As a next step, the post-receptor events induced by TNF were examined. Although the signal transduction pathways for TNF have not been delineated clearly, the actions of many other hormones are mediated by the reversible phosphorylation of specific enzymes or target proteins. The present study demonstrated that TNF induces phosphorylation of 28 kDa protein (p28). Two dimensional soidum dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) resolved the 28kDa phosphoprotein into two isoforms having pIs of 6.2 and 6.1. The pIs and relative molecular weight of p28 were consistent with those of a previously characterized mRNA cap binding protein. mRNA cap binding proteins are a class of translation initiation factors that recognize the 7-methylguanosine cap structure found on the 5' end of eukaryotic mRNAs. In vitro, these proteins are defined by their specific elution from affinity columns composed of 7-methylguanosine 5'-triphosphate($m^7$GTP)-Sepharose. Affinity purification of mRNA cap binding proteins from control and TNF treated ME-180 cells proved that TNF rapidly stimulates phosphorylation of an mRNA cap binding protein. Phosphorylation occurred in several cell types that are important in vitro models of TNF action. The mRNA cap binding protein phosphorylated in response to TNF treatment was purifice, sequenced, and identified as the proto-oncogene product eukaryotic initiation factor-4E(eIF-4E). These data show that phosphorylation of a key component of the cellular translational machinery is a common early event in the diverse cellular actions of TNF.

• Journal of Life Science
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• v.27 no.10
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• pp.1215-1224
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• 2017

Until now, various oncogenic pathways were idenfied. The accumulation of DNA mutation induces genomic instability in the cell, and it makes cancer. The development of bioinformatics and genomics, to find the precise and reliable biomarker is available. This biomarker could be applied the early-dignosis, prediction and convalescence of cancer. Recently, Transposable elements (TEs) have been attracted as the regulator of genes, because they occupy a half of human genome, and the cause of various diseases. TEs induce DNA mutation, as well as the regulation of gene expression, that makes to cancer development. So, we confirmed the relationship between TEs and colon cancer, and provided the clue for colon cancer biomarker. First, we confirmed long interspersed nuclear element-1 (LINE-1), Alu, and long terminal repeats (LTRs) and their relationship to colon cancer. Because these elements have large composition and enormous effect to the human genome. Interestingly, colon cancer specific patterns were detected, such as the hypomethylation of LINE-1, LINE-1 insertion in the APC gene, hypo- or hypermethylation of Alu, and isoform derived from LTR insertion. Moreover, hypomethylation of LINE-1 in proto-oncogene is used as the biomarker of colon cancer metastasis, and MLH1 mutation induced by Alu is detected in familial or hereditary colon cancer. The genes, effected by TEs, were analyzed their expression patterns by in silico analysis. Then, we provided tissue- and gender-specific expression patterns. This information can provide reliable cancer biomarker, and apply to prediction and diagnosis of colon cancer.