Tumour stromal cells differ from its normal counterpart. We have shown that tumour endothelial cells (TECs) isolated from tumour tissues are also abnormal. Furthermore, we found that mRNAs of ...vascular endothelial growth factor-A (VEGF-A) and cyclooxygenase-2 (COX-2) were upregulated in TECs. Vascular endothelial growth factor-A and COX-2 are angiogenic factors and their mRNAs contain an AU-rich element (ARE). AU-rich element-containing mRNAs are reportedly stabilised by Hu antigen R (HuR), which is exported to the cytoplasm.
Normal endothelial cell (NEC) and two types of TECs were isolated. We evaluated the correlation of HuR and accumulation of VEGF-A and COX-2 mRNAs in TECs and effects of HuR on biological phenotypes of TECs.
The HuR protein was accumulated in the cytoplasm of TECs, but not in NECs. Vascular endothelial growth factor-A and COX-2 mRNA levels decreased due to HuR knockdown and it was shown that these ARE-mRNA were bound to HuR in TECs. Furthermore, HuR knockdown inhibited cell survival, random motility, tube formation, and Akt phosphorylation in TECs.
Hu antigen R is associated with the upregulation of VEGF-A and COX-2 mRNA in TECs, and has an important role in keeping an angiogenic switch on, through activating angiogenic phenotype in tumour endothelium.
Aminomethylphenylnorharman (AMPNH) and aminophenylnorharman (APNH) are mutagenic norharman derivatives obtained from o-toluidine and aniline, respectively. APNH is carcinogenic to the urinary bladder ...of rats and present in urine samples of healthy volunteers, indicating that norharman derivatives may be associated with cancer development in the urinary bladder of humans. To evaluate the possible role of AMPNH and APNH in bladder carcinogenesis, we examined the formation of gamma-H2AX, a DNA damage response marker, in the urinary bladder of rats. Seven-week-old male F344 rats were treated with 400 ppm AMPNH or 40 ppm APNH in the diet for 4 weeks. Animals were killed at the end of administration or after 2 weeks of recovery, and immunohistochemistry for gamma-H2AX and Ki67, a cell proliferation marker, was performed. At week 4, gamma-H2AX formation in bladder epithelial cells was significantly increased by APNH treatment as compared with that in controls. AMPNH also induced upregulation of gamma-H2AX formation, although there was no statistical significance. After the recovery period, gamma-H2AX-positive cells were reduced but remained significantly higher in AMPNH and APNH groups than in the control group. Ki67-positive cells were significantly increased by AMPNH and APNH at week 4 and reduced to the same level as the control after 2 weeks of recovery. Expression of KRT14, a bladder stem cell marker, was also increased in the basal layer by the two norharman derivatives. Thus, AMPNH and APNH showed in vivo genotoxicity in the bladder epithelium of rats, and APNH may be a potent causative agent of bladder carcinogenesis. To evaluate the role of norharman derivatives in bladder carcinogenesis, we examined gamma-H2AX formation in the urinary bladder of male rats treated with aminomethylphenylnorharman (AMPNH) or aminophenylnorharman (APNH) for 4 weeks. gamma-H2AX formation in the urothelium was increased in both groups at week 4. After 2 weeks of recovery, gamma-H2AX-positive cells remained significantly-high levels in both groups. Thus, AMPNH and APNH showed in vivo genotoxicity in the bladder epithelium, and APNH may be a potent causative agent of bladder carcinogenesis.
Aminomethylphenylnorharman (AMPNH) and aminophenylnorharman (APNH) are mutagenic norharman derivatives obtained from o‐toluidine and aniline, respectively. APNH is carcinogenic to the urinary bladder ...of rats and present in urine samples of healthy volunteers, indicating that norharman derivatives may be associated with cancer development in the urinary bladder of humans. To evaluate the possible role of AMPNH and APNH in bladder carcinogenesis, we examined the formation of γ‐H2AX, a DNA damage response marker, in the urinary bladder of rats. Seven‐week‐old male F344 rats were treated with 400 ppm AMPNH or 40 ppm APNH in the diet for 4 weeks. Animals were killed at the end of administration or after 2 weeks of recovery, and immunohistochemistry for γ‐H2AX and Ki67, a cell proliferation marker, was performed. At week 4, γ‐H2AX formation in bladder epithelial cells was significantly increased by APNH treatment as compared with that in controls. AMPNH also induced upregulation of γ‐H2AX formation, although there was no statistical significance. After the recovery period, γ‐H2AX‐positive cells were reduced but remained significantly higher in AMPNH and APNH groups than in the control group. Ki67‐positive cells were significantly increased by AMPNH and APNH at week 4 and reduced to the same level as the control after 2 weeks of recovery. Expression of KRT14, a bladder stem cell marker, was also increased in the basal layer by the two norharman derivatives. Thus, AMPNH and APNH showed in vivo genotoxicity in the bladder epithelium of rats, and APNH may be a potent causative agent of bladder carcinogenesis.
To evaluate the role of norharman derivatives in bladder carcinogenesis, we examined γ‐H2AX formation in the urinary bladder of male rats treated with aminomethylphenylnorharman (AMPNH) or aminophenylnorharman (APNH) for 4 weeks. γ‐H2AX formation in the urothelium was increased in both groups at week 4. After 2 weeks of recovery, γ‐H2AX‐positive cells remained significantly‐high levels in both groups. Thus, AMPNH and APNH showed in vivo genotoxicity in the bladder epithelium, and APNH may be a potent causative agent of bladder carcinogenesis.
E4orf6 is one of the oncogene products of adenovirus, and it also has an important role for transportation of cellular and viral messenger RNA (mRNA) during the late phase of virus infection. We ...previously revealed that E4orf6 controls the fate of AU-rich element (ARE) containing mRNA by perturbing the chromosome maintenance region 1-dependent export mechanism. Here, we show that E4orf6 stabilizes ARE-mRNA through the region required for its oncogenic activity and ubiquitin E3 ligase assembly. Cells that failed to stabilize ARE-mRNA after HuR knockdown were unable to produce colonies in soft agar, even when E4orf6 was expressed. Furthermore, the stabilized ARE-mRNA induced the transformation of rodent immortalized cells. These findings indicate that stabilized ARE-mRNA is necessary, if not all, for the oncogenic activity of E4orf6 and has the potential to transform cells, at least under a certain condition.
HuR, a ubiquitously expressed member of the Hu protein family that binds and stabilizes an AU-rich element (ARE)-containing mRNAs, is known to shuttle between the nucleus and the cytoplasm via ...several export pathways. When normal cells were treated with heat shock, HuR was exported to the cytoplasm in a chromosome maintenance region 1 (CRM1)-dependent manner. However, in this study, we demonstrate that HuR is exported to the cytoplasm in oral cancer cells even if the cells were treated with the inhibitor of the CRM1-independent export pathway. Immunohistochemical and biochemical analyses showed that HuR existed in both the cytoplasm and the nucleus in oral cancer cells, such as HSC-3 and Ca9.22, but existed entirely inside the nucleus in normal cells. AU-rich element-mRNAs were also exported to the cytoplasm and stabilised in the oral cancer cells, which were inhibited by HuR knockdown. This export of HuR was not affected by at least 7 h of treatment of leptomycin B (LMB), which is an inhibitor of the CRM1-dependent export pathway. These findings suggest that HuR is exported to the cytoplasm in oral carcinoma cells in a different manner from that of normal cells, and is likely to occur through the perturbation of a normal export pathway.
The MTV experiment (
M
ott Polarimetry for
T
-
V
iolation Experiment) is running at TRIUMF, to search for a large
T
-violating transverse electron-polarization in polarized
8
Li
β
-decay. We aim at ...reaching precision of 10
−4
for the
R
-correlation, which is defined as a
T
-violating triple vector correlation in the
β
-decay rate function. A Mott polarimeter system using a CDC (
C
ylindrical
D
rift
C
hamber) is used to measure the left-right scattering asymmetry in the Mott scattering from a thin metal foil. In the present study, we aim to discuss systematic effects in Mott polarimetry using the CDC.
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![[gamma]-H2AX formation in t...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/0260-437X/small "[gamma]-H2AX formation in the urinary bladder of rats treated with two norharman derivatives obtained from o-toluidine and aniline")
