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33.
Mi Kyung Kwak Daniel T. Johnson Chunfang Zhu Suk Hyung Lee Ding-Wei Ye Richard Luong Zijie Sun 《PloS one》2013,8(1)
The PTEN tumor suppressor gene is frequently inactivated in human prostate cancer. Using Osr1 (odd skipped related 1)-Cre mice, we generated a novel conditional Pten knockout mouse strain, PtenLoxP:Osr1-Cre. Conditional biallelic and monoallelic Pten knockout mice were viable. Deletion of Pten expression was detected in the prostate of PtenLoxP/LoxP:Osr1-Cre mice as early as 2 weeks of age. Intriguingly, PtenLoxP/LoxP:Osr1-Cre mice develop high-grade prostatic intraepithelial neoplasms (PINs) with high penetrance as early as one-month of age, and locally invasive prostatic tumors after 12-months of age. PtenLoxP/+:Osr1-Cre mice show only mild oncogenic changes after 8-weeks of age. Castration of PtenLoxP/LoxP:Osr1-Cre mice shows no significant regression of prostate tumors, although a shift of androgen receptor (AR) staining from the nuclei to cytoplasm is observed in Pten null tumor cells of castrated mice. Enhanced Akt activity is observed in Pten null tumor cells of castrated PtenLoxP/LoxP:Osr1-Cre. This study provides a novel mouse model that can be used to investigate a primary role of Pten in initiating oncogenic transformation in the prostate and to examine other genetic and epigenetic changes that are required for tumor progression in the mouse prostate. 相似文献
34.
Myoung Jae Kang Kyoung Min Kim Jun Sang Bae Ho Sung Park Ho Lee Myoung Ja Chung Woo Sung Moon Dong Geun Lee Kyu Yun Jang 《Translational oncology》2013,6(3):282-289
BACKGROUND: Clear cell renal cell carcinoma (CRCC) is the most common malignant tumor of the kidney, and the clinical outcome of CRCC is related with the metastatic potential of CRCC. A significant proportion of metastatic CRCC remains incurable. Recently, immunotherapy against specific targets such as programmed death 1 (PD1) has been adapted for fatal cases of CRCC. MATERIALS AND METHODS: In this study, we aimed to evaluate the potential of tumor-infiltrating PD1-positive lymphocytes or FoxP3-positive regulatory T cells (Tregs) as predictors of the metastatic potential or prognosis of CRCC and investigate possible correlations with Epstein-Barr virus (EBV) infection in 199 cases of CRCC. RESULTS: PD1 positivity, high Treg number, and EBV infection all predicted poor overall survival (OS) by univariate analysis. PD1 positivity and high Treg numbers were also significantly correlated with more distant metastatic relapse (DMR) and poor relapse-free survival (RFS) by univariate analysis. PD1 positivity and high Treg number were independent prognostic indicators for OS. In addition, PD1 positivity was an independent predictor of RFS and DMR. EBV infection was an independent predictor of OS of CRCC. CONCLUSION: This study demonstrates that intratumoral infiltration of PD1-positive or FoxP3-positive lymphocytes can be used as significant prognostic indicators of CRCC and PD1 positivity could be very helpful in the prediction of latent distant metastasis of CRCCs. Therefore, evaluation of the infiltration of PD-positive cells or Tregs in CRCC may be useful diagnostic tools for the selection of patients who could benefit from PD1- or Treg-based immunotherapy. 相似文献
35.
Jung Ok Park Do‐Young Choi Dong‐Sic Choi Hee Joung Kim Jeong Won Kang Jae Hun Jung Jeong Hwa Lee Jayoung Kim Michael R. Freeman Kye Young Lee Yong Song Gho Kwang Pyo Kim 《Proteomics》2013,13(14):2125-2134
Microvesicles (MVs, also known as exosomes, ectosomes, microparticles) are released by various cancer cells, including lung, colorectal, and prostate carcinoma cells. MVs released from tumor cells and other sources accumulate in the circulation and in pleural effusion. Although recent studies have shown that MVs play multiple roles in tumor progression, the potential pathological roles of MV in pleural effusion, and their protein composition, are still unknown. In this study, we report the first global proteomic analysis of highly purified MVs derived from human nonsmall cell lung cancer (NSCLC) pleural effusion. Using nano‐LC–MS/MS following 1D SDS‐PAGE separation, we identified a total of 912 MV proteins with high confidence. Three independent experiments on three patients showed that MV proteins from PE were distinct from MV obtained from other malignancies. Bioinformatics analyses of the MS data identified pathologically relevant proteins and potential diagnostic makers for NSCLC, including lung‐enriched surface antigens and proteins related to epidermal growth factor receptor signaling. These findings provide new insight into the diverse functions of MVs in cancer progression and will aid in the development of novel diagnostic tools for NSCLC. 相似文献
36.
In plants, the extracellular space (apoplast) is one of the main places where exchange of molecules occurs between cells. Not only is this compartment involved in the storage of multiple metabolites and ions, including calcium and protons, but it also plays a role in the transmission of signaling molecules for cell-to-cell communication. It has recently been shown multiple times that these two aspects are linked and can influence each other. In particular, apoplast pH was shown as a primary regulator of auxin (IAA) transport in Arabidopsis thaliana. To prove the role of apoplastic pH, we have developed a protocol for apoplastic fluid extraction from Arabidopsis leaves, followed by pH determination using the 8-hydroxypyrene-1,3,6-trisulfonic acid (HPTS) fluorescent dye. This technique successfully allows one to monitor apoplastic pH variations among different plant lines and to link changes in apoplastic pH to cellular responses in the plant. 相似文献
37.
Jina Park Jeongmi Lee Jaewon Shim Woongsu Han Jinu Lee Yong Chul Bae Yun Doo Chung Chul Hoon Kim Seok Jun Moon 《PLoS genetics》2013,9(9)
Mechanically gated ion channels convert sound into an electrical signal for the sense of hearing. In Drosophila melanogaster, several transient receptor potential (TRP) channels have been implicated to be involved in this process. TRPN (NompC) and TRPV (Inactive) channels are localized in the distal and proximal ciliary zones of auditory receptor neurons, respectively. This segregated ciliary localization suggests distinct roles in auditory transduction. However, the regulation of this localization is not fully understood. Here we show that the Drosophila Tubby homolog, King tubby (hereafter called dTULP) regulates ciliary localization of TRPs. dTULP-deficient flies show uncoordinated movement and complete loss of sound-evoked action potentials. Inactive and NompC are mislocalized in the cilia of auditory receptor neurons in the dTulp mutants, indicating that dTULP is required for proper cilia membrane protein localization. This is the first demonstration that dTULP regulates TRP channel localization in cilia, and suggests that dTULP is a protein that regulates ciliary neurosensory functions. 相似文献
38.
Jung Hyun Yoon Kyung Hwa Han Eun-Kyung Kim Hee Jung Moon Min Jung Kim Young Joo Suh Ji Soo Choi Byeong-Woo Park 《PloS one》2013,8(2)
Introduction
To assess whether the value of CYFRA21-1 in the aspirates of ultrasonography-guided fine-needle aspiration biopsy (US-FNAB) can contribute to improving the performances of US-FNAB in the diagnosis of axillary lymph node (LN) metastasis in breast cancer patients.Methods
US-FNAB was performed in 156 axillary LNs in 152 breast cancer patients (mean age: 51.4 years, range: 17–92 years). Concentrations of CYFRA21-1 were measured from washouts of the syringe used during US-FNAB. Tumor marker concentrations, US-FNAB, intraoperative sentinel node biopsy (SNB), and surgical pathology results were reviewed and analyzed. For comparison, the values of CEA and CA15-3 were also measured from washouts.Results
Among the 156 LNs, 75 (48.1%) were benign, and 81 (51.9%) were metastases. Mean concentrations of CYFRA21-1 were significantly higher in metastasis compared to benign LNs (P<0.001). US-FNAB combined to CYFRA21-1 showed significantly higher sensitivity, NPV, and accuracy compared to US-FNAB alone (all values P<0.05). All diagnostic indices of US-FNAB combined to CYFRA21-1 were significantly higher compared to US-FNAB combined with CEA or CA15-3 (all P<0.001). Of the 28 metastatic LNs which showed metastasis on SNB, CYFRA21-1 showed higher positive rate of 75.0% (CEA or CA15-3∶60.7%, P = 0.076).Conclusion
Measuring CYFRA 21-1 concentrations from US-FNAB aspirates improves sensitivity, NPV, and accuracy of US-FNAB alone, and may contribute to reducing up to 75.0% of unnecessary intraoperative SNB. Compared to CEA or CA15-3, CYFRA21-1 shows significantly higher performances when combined to US-FNAB in the preoperative diagnosis of LN metastasis in breast cancer patients. 相似文献39.
Dae Hwan Lee Ji Hyeon Ahn Joon Ha Park Bing Chun Yan Jeong-Hwi Cho In Hye Kim Jae-Chul Lee Sang-Hun Jang Myoung Hyo Lee In Koo Hwang Seung Myung Moon Bonghee Lee Jun Hwi Cho Hyung-Cheul Shin Jin Sang Kim Moo-Ho Won 《Cellular and molecular neurobiology》2013,33(5):615-624
Aging is an inevitable process that occurs in the whole body system accompanying with many functional and morphological changes. Inflammation is known as one of age-related factors, and inflammatory changes could enhance mortality risk. In this study, we compared immunoreactivities of inflammatory cytokines, such as interleukin (IL)-2 (a pro-inflammatory cytokine), its receptor (IL-2R), IL-4 (an anti-inflammatory cytokine), and its receptor (IL-4R) in the cervical and lumbar spinal cord of young adult (2–3 years old) and aged (10–12 years old) beagle dogs using immunohistochemistry and western blotting. IL-2 and IL-2R-immunoreactive nerve cells were found throughout the gray matter of the cervical and lumbar spinal cord of young adult and aged dogs. In the spinal cord neurons of the aged dog, immunoreactivity and protein levels were apparently increased compared with those in the young adult dog. Change patterns of IL-4- and IL-4R-immunoreactive cells and their protein levels were also similar to those in IL-2 and IL-2R; however, IL-4 and IL-4R immunoreactivity in the periphery of the neuronal cytoplasm in the aged dog was much stronger than that in the young adult dog. These results indicate that the increase of inflammatory cytokines and their receptors in the aged spinal cord might be related to maintaining a balance of inflammatory reaction in the spinal cord during normal aging. 相似文献
40.
Ae Kyung Park Jin Ho Moon Eun Hyuk Jang Hyun Park In Young Ahn Ki Seog Lee Young Min Chi 《Proteins》2013,81(3):531-537
Glutathione‐S‐transferases have been identified in all the living species examined so far, yet little is known about their function in marine organisms. In a previous report, the recently identified GST from Antarctic bivalve Laternula elliptica (LeGST) was classified into the rho class GST, but there are several unique features of LeGST that may justify reclassification, which could represent specific shellfish GSTs. Here, we determined the crystal structure of LeGST, which is a shellfish specific class of GST. The structural analysis showed that the relatively open and wide hydrophobic H‐site of the LeGST allows this GST to accommodate various substrates. These results suggest that the H‐site of LeGST may be the result of adaptation to their environments as sedentary organisms. Proteins 2013. © 2012 Wiley Periodicals, Inc. 相似文献