• BMB Reports
• /
• 제34권2호
• /
• pp.156-165
• /
• 2001

Leptin is a circulating non-glycosylated protein that is mainly produced in adipocytes. Leptin acts in the brain to regulate food intake and energy expenditure. Previously we reported our success in the isolation of a partial cDNA of the long form of the leptin receptor, OB-Rb, from rat spleen, and showed that leptin might also play a role in peripheral immune organs. In the present study, for the first time, the complete coding region of OB-Rb cDNA was cloned from rat splenocytes, and its nucleotide sequence was determined. The cDNA was then further expressed in E. coli and mammalian cells, thereby confirming the functional integrity of this receptor. Prokaryotically overexpressed OB-R protein was then used as an immunizing antigen in BALE/c mice to produce leptin receptor-specific antibodies. By using them, we confirmed the cell surface expression of OB-Rb in transfected CHO cells. It is our belief that the reagents, as produced in this study, will be of great use in further studies of the biological role of rat leptin.

• 대한화장품학회지
• /
• 제41권3호
• /
• pp.263-268
• /
• 2015

본 연구는 오디씨 에탄올 추출물(MSE)의 멜라닌 합성 저해 효과를 밝히는 것이다. 먼저 MSE의 melan-a 세포를 이용한 멜라닌 합성 저해 실험결과, 독성을 보이지 않는 $10{\mu}g/mL$의 농도까지 멜라닌 합성 저해 효과를 나타내었다. 또한 tyrosinase, tyrosinase-related protein-1 (TRP-1) 단백질의 발현이 저해되었으며, extracelluar signal-regulated protein kinase (ERK)의 발현을 농도 의존적으로 증가시키는 MSE의 기전을 확인하였다. 뿐만 아니라, 제브라피쉬를 이용한 in vivo 모델의 실험에서도 색소 발생이 저해됨을 관찰하였다. 따라서 오디씨로 부터 획득한 에탄올 추출물이 ERK 단백질의 발현으로 인해 멜라닌 생합성을 억제할 수 있음을 밝혔다.

• Journal of Plant Biology
• /
• 제22권4호
• /
• pp.95-100
• /
• 1979

As a part of the studies on the regulatory mechanism of gene expression by $GA_{3}$ , the effects of $GA_{3}$ on the protein biosynthesis and phosphorylation in maize seedlings were investigated. 1. The optimum concentration of $GA_{3}$ for the stimulation of the protein biosynthesis was 0.3mM. 2. The protein biosynthesis was remarkably increase by $GA_{3}$ during the germination. The reason for the decrease in the protein biosynthesis by 48hrs. after germination seems to be a staggered gene expression, and/or increases in protease and RNase activities. 3. The ratio of the amount of the newly synthesized protein in germinating seeds treated with $GA_{3}$ to the amount of proteins secreted into the endosperm was similar to that ratio in control. According to this result, it seems that $GA_{3}$ stimulates only the expression of certain definite genes. 4. By the treatment with $GA_{3}$, the rates of biosynthesis and phosphorylation of proteins were increased up to about 1.5 times during germination and 6 times by 72hrs. after germination, respectively. The ratio of the total soluble proteins to the phosphorpoteins considerably increased in the early germination stage (24hrs.) but decreased after 24hrs. According to the above mentioned results, the stimulation of the phosphorylation of proteins of $GA_{3}$ seems to be attributed to the increases in the activities of protein kinases.

• BMB Reports
• /
• 제32권2호
• /
• pp.112-118
• /
• 1999

The presence of hypoxic cells in solid tumors has long been considered a problem in cancer treatment such as in radiation therapy or treatment with some anticancer drugs. It has been suggested that hypoxic cells are involved in the development of a more aggressive phenotype and contribute to metastasis. In this study, as an attempt to understand how tumor cells adapt to hypoxic stress, we investigated the regulation of the hypoxia-induced expression of proteins that control essential processes of tumor cell survival and angiogenesis. We first examined whether hypoxia induces stress protein gene expression of murine solid tumor RIF cells. We also examined hypoxia-induced changes in angiogenic gene expression in these cells. Finally, we investigated the association of the elevated levels of stress proteins with the regulation of hypoxia-induced angiogenic gene expression. Results demonstrated that hypoxia induced the expression of the erythropoietin (EPO) gene and at least two major members of stress proteins, heat shock protein 70 (HSP70) and 25 (HSP25) in RIF tumor cells. Evidence that the expression of EPO gene was greatly potentiated in TR cells suggested that the elevated levels of HSPs may play an important role in the regulation of the hypoxia-induced EPO gene expression. One of the RIF variant cell lines, TR, displays elevated levels of HSPs constitutively. Taken together, our results suggest that a hypoxic tumor microenvironment may promote the survival and malignant progression of the tumor cells by temporarily increasing the level of stress proteins and expressing angiogenic genes. We suspect that stress proteins may be associated with the increase of the angiogenic potential of tumor cells under hypoxia.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권6호
• /
• pp.2495-2499
• /
• 2015

Mitogen-activated protein kinase/extracellular signal-regulated kinase kinase kinase 3 (MEKK3) is an important serine/threonine protein kinase and a member of the MAPK family. MEKK3 can effectively activate the MEK/ERK signaling pathway and promote an autocrine growth loop critical for tumor genesis, cell proliferation, terminal differentiation, apoptosis and survival. To explore the relationship between MEKK3 and cell apoptosis, clinicopathology and prognosis, we characterize the expression of MEKK3, pERK and FoxP3 in the renal clear cell carcinoma (RCCC). Protein expression was detected by tissue microarray and immunochemistry in 46 cases of RCCC and 28 control cases. Expression levels of CD3+,CD3+CD4+,CD3+CD8+,CD4+CD25+, CD4+CD25+ FoxP3+ were assessed by flow cytometry and analyzed for their association with pathological factors, correlation and prognosis in RCCC. Expression of MEKK3, pERK and FoxP3 was significantly up-regulated in RCCC as compared to control levels (p<0.01), associated with pathological grade (p<0.05)and clinical stage (p<0.05). CD4+CD25+ Foxp3+ Treg cells were also significantly increased in RCCC patients (p<0.05). Cox multivariate regression analysis showed that MEKK3, pERK expression and patholigical stage were independent prognostic factors in patients with RCCC (p<0.05). MEKK3 can be used as an important marker of early diagnosis and prognostic evaluation in RCCC. It may be associated with imbalance of anti-tumor immunity and overexpression of pERK. Expression of MEKK3 and pERK are significantly increased in RCCC, with protein expression and clinical stage acting as independent prognostic factors.

• Asian Pacific Journal of Cancer Prevention
• /
• 제14권12호
• /
• pp.7295-7300
• /
• 2013

Lung cancer is the most common cause of cancer-related death in the world. The main types are small-cell lung carcinoma (SCLC) and non-small-cell lung carcinoma (NSCLC), the latter including squamous cell carcinoma (SCC), adenocarcinoma and large cell carcinoma. NSCLCs account for about 80% of all lung cancer cases. Microcephalin (MCPH1), also called BRIT1 (BRCT-repeat inhibitor of hTERT expression), plays an important role in the maintenance of genomic stability. Recently, several studies have provided evidence that the expression of MCPH1 gene is decreased in several different types of human cancers. We evaluated the expression of protein MCPH1 in 188 lung cancer and 20 normal lung tissues by immunohistochemistry. Positive MCPH1 staining was found in all normal lung samples and only some cancerous tissues. MCPH1-positive cells were significantly lower in lung carcinoma compared with normal tissues. Furthermore, we firstly found that MCPH1 expression in lung adenocarcinoma is higher than its expression in squamous cell carcinoma. Change in MCPH1 protein expression may be associated with lung tumorigenesis and may be a useful biomarker for identification of pathological types of lung cancer.

• 대한한의학회지
• /
• 제41권2호
• /
• pp.43-57
• /
• 2020

Objectives: The purpose of this study was to investigate the effect of Phellinus linteus cheonghyeol plus (PLCP) on antioxidant and inhibition of inflammatory factor expression associated with dyslipidemia in HUVEC. Methods: The scavenging activity of DPPH and ABTS radical of PLCP was measured in HUVEC. The expression levels of NF-κB, p-IκBα, ERK, JNK, and p38 proteins were measured after treating with TNF-α in HUVEC. The expression levels of MCP-1, ICAM-1, and VCAM-1 mRNA and biomarkers were measured after treatment with TNF-α in HUVEC Results: 1. PLCP increases DPPH and ABTS radical scavenging activity in a concentration dependent manner. 2. PLCP significantly decreased the concentration of NF-κB, p-IκBα, ERK, JNK protein compared to the control at concentrations of 100 ㎍/㎖ or more, and significantly decreased concentration of p38 protein at all concentrations. 3. PLCP significantly decreased MCP-1 mRNA expression levels at 100㎍/㎖ or more compared to the control. ICAM-1 and VCAM-1 mRNA expression levels were significantly reduced at all concentrations compared to the control. MCP-1, ICAM-1 protein expression levels were significantly reduced compared to the control at concentrations of 100 ㎍/㎖ or more, and VCAM-1 protein expression levels were reduced at all concentrations. Conclusions: These results suggest that PLCP has an antioxidant effect, and it has been experimentally confirmed that it can prevent or inhibit inflammatory diseases caused by dyslipidemia due to its inhibitory effect on inflammation-related factors in HUVEC.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권8호
• /
• pp.4001-4005
• /
• 2012

Backgrouds: The hedgehog (Hh) signaling pathway is composed of patched (PTCH) and smoothened (SMO), two transmembrane proteins, and downstream glioma-associated oncogene homolog (Gli) transcription factors. Hh signaling plays a pathological role in the occurrence and development of various cancers. Methods: To investigate the expression of SMO protein in colon cancer and its association with clinicopathological parameters and postoperative liver metastasis, immunohistochemistry was performed with paraffin-embedded specimens of 96 cases. Relationships between SMO protein expression and clinicopathological parameters, postoperative liver metastasis were analyzed. Results: IHC examination showed that SMO protein expression was significantly increased in colon cancer tissues compared to normal colon tissues (P = 0.042), positively related to lymph node metastases (P = 0.018) and higher T stages (P = 0.026). Postoperative live metastasis-free survival was significantly longer in the low SMO expression group than in those with high SMO expression ($48.7{\pm}8.02$ months vs $28.0{\pm}6.86$ months, P=0.036). Multivariate analysis showed SMO expression level to be an independent prognostic factor for postoperative live metastasis-free survival (95% confidence interval [CI] =1.46-2.82, P = 0.008). Conclusions: Our results suggest that in patients with colon cancer, the SMO expression level is an independent biomarker for postoperative liver metastasis, and SMO might play an important role in colon cancer progression.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권4호
• /
• pp.1183-1186
• /
• 2012

Objective: To observe the effect of insulin-like growth factor-1 (IGF-1) on bone morphogenetic protein (BMP)-2 expression in hepatocellular carcinoma SMMC7721 cells. Methods: Cells were divided into blank control, IGF-1, IGF-1 + SB203580, and SB203580 groups. SB203580 was used to block the p38 MAPK signaling pathway. Changes in the expression of BMP-2, p38 MAPK, and phosphorylated p38, MERK, ERK and JNK were determined using reverse transcription polymerase chain reactions (RT-PCR) and Western blot analysis. Results: Protein expression of phosphorylated BMP-2, MERK, ERK, and JNK was significantly up-regulated by IGF-1 compared with the control group ($1.138{\pm}0.065$ vs. $0.606{\pm}0.013$, $0.292{\pm}0.005$ vs. $0.150{\pm}0.081$, $0.378{\pm}0.006$ vs. $0.606{\pm}0.013$, and $0.299{\pm}0.015$ vs. $0.196{\pm}0.017$, respectively; P<0.05). Levels of BMP-2 and phosphorylated MERK and JNK were significantly reduced after blocking of the p38MAPK signaling pathway ($0.494{\pm}0.052$ vs. $0.165{\pm}0.017$, $0.073{\pm}0.07$ vs. $0.150{\pm}0.081$, and $0.018{\pm}0.008$ vs. $0.196{\pm}0.017$, respectively; P<0.05), but such a significant difference was not observed for phosphorylated ERK protein expression ($0.173{\pm}0.07$ vs. $0.150{\pm}0.081$, P>0.05). Conclusion: IGF-1 can up-regulate BMP-2 expression, and p38 MAPK signaling pathway blockage can noticeably reduce the up-regulated expression. We can conclude that the up-regulatory effect of IGF-1 on BMP-2 expression is realized through the p38 MAPK signaling pathway.

• Asian Pacific Journal of Cancer Prevention
• /
• 제14권5호
• /
• pp.2851-2857
• /
• 2013

Objective: REPS2 plays important roles in inhibiting cell proliferation, migration and in inducing apoptosis of cancer cells, now being identified as a useful biomarker for favorable prognosis in prostate and breast cancers. The purpose of this study was to assess REPS2 expression and to explore its role in esophageal squamous cell carcinoma (ESCC). Methods: Protein expression of REPS2 in ESCCs and adjacent non-cancerous tissues from 120 patients was analyzed by immunohistochemistry and correlated with clinicopathological parameters and patient outcome. Additionally, thirty paired ESCC tissues and four ESCC cell lines and one normal human esophageal epithelial cell line were evaluated for REPS2 mRNA and protein expression levels by quantitative RT-PCR and Western blotting. Results: REPS2 mRNA and protein expression levels were down-regulated in ESCC tissues and cell lines. Low protein levels were significantly associated with primary tumour, TNM stage, lymph node metastasis and recurrence (all, P < 0.05). Survival analysis demonstrated that decreased REPS2 expression was significantly associated with shorter overall survival and disease-free survival (both, P < 0.001), especially in early stage ESCC patients. When REPS2 expression and lymph node metastasis status were combined, patients with low REPS2 expression/lymph node (+) had both poorer overall and disease-free survival than others (both, P < 0.001). Cox multivariate regression analysis further revealed REPS2 to be an independent prognostic factor for ESCC patients. Conclusions: Our findings demonstrate that downregulation of REPS2 may contribute to malignant progression of ESCC and represent a novel prognostic marker and a potential therapeutic target for ESCC patients.