Biomedical subjects

Toshiyuki Nakayama

Publications and source records attributed to Toshiyuki Nakayama.

At least 19 recordsLinked to original sources

PubMed2007

Expression of p-STAT3 in human gastric carcinoma: significant correlation in tumour invasion and prognosis.

Signal transducers and activators of transcription (STATs) belong to a family of transcription factors activated in response to cytokines and growth factors. Constitutive activation of STAT3 has been observed in a growing number of tumour-derived cell lines, as well as in tumor specimens from human cancers. Our aim was to determine the relationship between the expression of phosphorylated STAT3 (p-STAT3) and clinicopathological factors in human gastric adenocarcinoma. One-hundred and eleven cases of surgically resected human gastric adenocarcinoma were studied by immunohistochemistry. Fifty-five (49.5%) cases showed positive staining for the p-STAT3 proteins. The expression of p-STAT3 was significantly correlated with several clinicopathological factors. Moreover, expression of p-STAT3 was detected by Western blot analysis in 2 different kinds of cultured human gastric carcinoma cell lines and 4 cases of gastric carcinoma tissue obtained at surgery. Western blot analysis confirmed the presence of p-STAT3 in these specimens. In univariate survival analysis, p-STAT3 expression was associated with inferior survival (p<0.05). Constitutive activation of STAT3 may play an important role in the tumorigenesis of gastric adenocarcinoma, and the detailed mechanism of STAT3 signaling pathway in gastric adenocarcinoma deserves further investigation.

Adenocarcinoma↗

PubMed2007

Operational lumped constant for FDG in normal adult male rats.

UNLABELLED: We determined an operational value for the lumped constant to be used in measurements of the local rate of cerebral glucose use (lCMR(glc)) with FDG in normal adult male rats. METHODS: The standard quantitative autoradiographic method was used with 2-deoxy-d-(14)C-glucose ((14)C-DG) and with (14)C-FDG in awake normal adult male rats. Timed arterial blood samples were drawn for 45 min after the bolus and assayed for plasma glucose and (14)C concentrations. At the end of the 45-min experimental period, the rats were killed, and their brains were removed and divided in half sagittally. One hemisphere was immediately frozen and assayed for local (14)C concentrations by quantitative autoradiography; the other was weighed, homogenized in t-octylphenoxypolyethoxyethanol solution, and assayed for (14)C concentrations in the whole brain by liquid scintillation counting. Paired rats (3 pairs), one in each pair receiving (14)C-DG and the other receiving (14)C-FDG, were studied in parallel on the same day. Additional unpaired animals (n = 8) were studied with either (14)C-DG or (14)C-FDG but not in parallel on the same day. To calculate the lCMR(glc) in rats studied with (14)C-FDG, the rate constants for (14)C-FDG were estimated from the (14)C-DG values determined for rats and the (14)C-FDG/(14)C-DG ratios determined for humans. In all of the rats studied with either (14)C-DG or (14)C-FDG, the lCMR(glc) was first calculated in 12 representative brain structures with the lumped constant of 0.48 previously determined for (14)C-DG in rats. The ratio of the lCMR(glc) thus determined with (14)C-FDG to that determined with (14)C-DG for each structure was then multiplied by the lumped constant for (14)C-DG to estimate the lumped constant for (14)C-FDG. The lCMR(glc) and the lumped constant for FDG in the brain as a whole were similarly estimated from the tracer concentrations in the brain homogenates. RESULTS: The mean values for the lumped constant for FDG were found to be 0.71 and 0.70 in the autoradiographic assays and the assays with brain homogenates, respectively. CONCLUSION: The appropriate value for the lumped constant to be used in determinations of the lCMR(glc) in normal adult male rat studies with (18)F-FDG and small-animal PET scanners is 0.71.

Animals↗

PubMed2006

Intranasal administration of E-selectin to induce immunological tolerization can suppress subarachnoid hemorrhage-induced vasospasm implicating immune and inflammatory mechanisms in its genesis.

Evidence that inflammatory and immune mechanisms may have a critical role in the development of vasospasm after subarachnoid hemorrhage is accumulating. We examined, therefore, whether induction of immunological tolerance to the adhesion molecule that is uniquely expressed on activated endothelium, E-selectin, could inhibit the vasospasm provoked by subarachnoid blood in a rat subarachnoid hemorrhage model. We found that intranasal instillation of E-selectin every other day for 10 days on a mucosal tolerization schedule suppressed delayed type hypersensitivity to E-selectin confirming tolerance to that molecule and markedly suppressed basilar artery spasm after subarachnoid hemorrhage. The results of this proof-of-concept study suggest that agents that can mimic the local effects of the mediators of mucosal tolerance could have therapeutic potential for the management of post-subarachnoid hemorrhage vasospasm.

Administration, Intranasal↗

PubMed2006

Expression of vascular endothelial growth factor and its receptors VEGFR-1 and 2 in gastrointestinal stromal tumors, leiomyomas and schwannomas.

AIM: To investigate the role of vascular endothelial growth factor (VEGF) and its receptors VEGFR-1 and 2 in the growth and differentiation of gastrointestinal stromal tumors (GISTs). METHODS: Thirty-three GISTs, 15 leiomyomas and 6 schwannomas were examined by immunohistochemistry in this study. RESULTS: VEGF protein was expressed in the cytoplasm of tumor cells, and VEGFR-1 and 2 were expressed both in the cytoplasm and on the membrane of all tumors. Immunohistochemical staining revealed that 26 GISTs (78.8%), 9 leiomyomas (60.0%) and 3 schwannomas (50.0%) were positive for VEGF; 24 GISTs (72.7%), 12 leiomyomas (80.0%) and 4 schwannomas (66.7%) were positive for VEGFR-1; 30 GISTs (90.9%), 5 leiomyomas (33.3%) and 4 schwannomas (66.7%) were positive for VEGFR-2. VEGFR-2 expression was statistically different between GISTs and leiomyomas (P < 0.0001). However, there was no correlation between the expression of VEGF pathway componenets and the clinical risk categories. CONCLUSION: Our results suggest that the VEGF pathway may play an important role in the differentiation of GISTs, leiomyomas and schwannomas.

Cell Proliferation↗

PubMed2006

Distribution of the 5-HT(1A) receptor antagonist [ (18)F]FPWAY in blood and brain of the rat with and without isoflurane anesthesia.

PURPOSE: To determine whether brain and plasma equilibrium of a proposed PET tracer for 5-HT(1A), [(18)F]FPWAY, can be achieved in a sufficiently short time for practical use of the brain to plasma equilibrium distribution ratio (DR) to monitor receptor availability with and without isoflurane anesthesia. METHODS: Awake (n=4) and isoflurane-anesthetized (n=4) rats were administered a continuous 60 min intravenous infusion of [(18)F]FPWAY with timed arterial blood sampling. Brains of the isoflurane-anesthetized rats were scanned with the ATLAS small animal PET scanner; awake rats were not. All rats were killed at 60 min and scanned postmortem for 15 min, followed by brain slicing for autoradiography. Several regions of interest (ROIs) were defined in the PET images as well as in the autoradiographic images. Regional DRs were calculated as total activity in the brain ROI divided by plasma [(18)F]FPWAY activity. RESULTS: DRs in the anesthetized animals were constant between 30 and 60 min, indicating that near equilibrium between brain and plasma had been achieved by approximately 30 min. DRs determined from postmortem PET data were higher in the isoflurane-anesthetized rats by 24% (not significant) and 33% (p=0.065) in whole brain and hippocampus, respectively. DRs determined from autoradiographic data were greater in isoflurane-anesthetized rats in medial hippocampus, lateral hippocampus, and cerebellum by 33% (p=0.054), 63% (p<0.01), and 32% (p<0.05), respectively. CONCLUSION: [(18)F]FPWAY could be an appropriate ligand for monitoring changes in receptor availability in the serotonergic system using a bolus/infusion paradigm. One possible explanation for higher DRs in anesthetized rats may be a reduction in endogenous 5-HT secretion under isoflurane anesthesia.

Anesthetics, Inhalation↗

PubMed2006

Expressions of sonic hedgehog, patched, smoothened and Gli-1 in human intestinal stromal tumors and their correlation with prognosis.

AIM: To investigate the role that the hedgehog (Hh) signaling pathway, which includes sonic hedgehog (Shh), Patched (Ptc), Smoothened (Smo) and Gli-1, plays in human gastrointestinal stromal tumors (GISTs). METHODS: Surgically resected specimens from patients with GISTs, leiomyomas and schwannomas were examined by immunohistochemical staining for aberrant expression of hedgehog signaling components, Shh, Ptc, Smo and Gli-1, respectively. RESULTS: In GISTs, 58.1% (18 of 31), 77.4% (24 of 31), 80.6% (25 of 31) and 58.1% (18 of 31) of the specimens stained positive for Shh, Ptc, Smo and Gli-1, respectively. In leiomyomas, 92.3% (12 of 13), 92.3% (12 of 13), 69.2% (9 of 13) and 92.3% (12 of 13) stained positive for Shh, Ptc, Smo and Gli-1, respectively. In schwannomas, 83.3% (5 of 6), 83.3% (5 of 6), 83.3% (5 of 6) and 100% (6 of 6) stained positive for Shh, Ptc, Smo and Gli-1, respectively. Immunohistochemistry revealed that the expressions of Shh and Gli-1 were significantly higher in leiomyomas than in GISTs (P < 0.05, respectively). Shh expression strongly correlated with the grade of tumor risk category and with tumor size (P < 0.05, respectively). However, the expressions of Ptc and Smo did not correlate with histopathological differentiation. CONCLUSION: These results suggest that the Hh signaling pathway may play an important role in myogenic differentiation and the malignant potential of human intestinal stromal tumors.

Cell Transformation, Neoplastic↗

PubMed2006

Expression of Ets-1 proto-oncoprotein in gastrointestinal stromal tumors, leiomyomas and schwannomas.

AIM: Gastrointestinal stromal tumors (GISTs) are rare. GISTs differ from other mesenchymal tumors of the gastrointestinal tract (e.g. leiomyomas and schwannomas). The purpose of this study was to investigate the role of Ets-1 in the growth and differentiation of GISTs. METHODS: Twenty-eight GISTs, nine leiomyomas and six schwannomas were examined by immunohistochemical staining method for Ets-1 in this study. Specimens were selected from surgical pathology archival tissues at Nagasaki University Hospital. RESULTS: Ets-1 protein was expressed in the cytoplasm of cells in all of these tumors. Immunohistochemical staining revealed that 27 GISTs (96.4%), six leiomyomas (66.7%), and five schwannomas (83.3%) were positive for Ets-1. Ets-1 expression was statistically different between GISTs and leiomyomas (P<0.005). However, there was no correlation between Ets-1 expression and clinical risk categories. CONCLUSION: Ets-1 plays an important role in the growth and differentiation of GISTs, leiomyomas and schwannomas.

Biomarkers, Tumor↗

PubMed2006

Expression of interleukin-11 and interleukin-11 receptor alpha in human colorectal adenocarcinoma; immunohistochemical analyses and correlation with clinicopathological factors.

AIM: There is strong evidence that interleukin-11 (IL-11) is involved in the regulation of tumor progression, cellular growth and differentiation. Recently, interleukin-11 receptor (IL-11R) has been detected on some cancer cells. In this study, we investigated the expression of IL-11 and IL-11R in colorectal adenocarcinoma. METHODS: To elucidate the involvement of IL-11 and IL-11Ra in human intestinal adenocarcinomas, we examined 115 cases of surgically resected human colonic adenocarcinoma and 11 cases of adenoma by immunohistochemistry and Western blotting. RESULTS: Among 115 cases of adenocarcinoma, 100 cases (87.0%) showed positive staining in the cytoplasm of carcinoma cells for the IL-11, and 87 cases (75.6%) were positive for the IL-11Ra. Six cases (54.5%) and four cases (36.4%) of 11 adenomas were positive for IL-11 and IL-11Ra, respectively. The expression of IL-11Ra correlated with the histological differentiation (P = 0.033503), the depth of tumor invasion (P = 0.006395), Dukes'classification (P = 0.015648) and lymphatic invasion (P = 0.003865). However, the expression of IL-11Ra was not correlated with the venous invasion and the presence of lymph node metastasis. The expression of IL-11 was not correlated with any clinicopathological factors. In Western blot analysis, two human colorectal carcinoma cell lines and four tissues of surgically resected human carcinoma expressed both IL-11 and IL-11Ra proteins. CONCLUSION: IL-11 and IL-11Ra are highly expressed in human colorectal adenocarcinoma and the IL-11Ra expression is correlated with clinicopathological factors. These findings suggest that the expression of IL-11Ra is an important factor for the invasion of human colorectal adenocarcinoma.

Adenocarcinoma↗

PubMed2006

Sucralfate protects intestinal epithelial cells from radiation-induced apoptosis in rats.

Radiotherapy for malignant pelvic disease is often followed by acute radiation colitis (ARC). It has been reported that sucralfate treatment has a protective effect against ARC, though the mechanisms of action are unknown. The effects of sucralfate on X-ray radiation-induced apoptosis was studied at 4 Gy in the colonic crypt cells of rats. Sucralfate enemas given prior to radiation resulted in the following: (1) reduction in number of apoptotic colonic crypt cells; (2) reduction in number of caspase-3 positive cells; (3) decreases in p53 accumulation and p21 expression; (4) decreases of Bax/Bcl-2 ratio. The protective effects of sucralfate against ARC may be partially due to the suppression of radiation-induced apoptosis by way of p53 in the colon and the protection of the colonic epithelial stem cell region.

Animals↗

PubMed2006

Activation of STAT3 is a marker of poor prognosis in human colorectal cancer.

It is known that the signal transducer and activator of transcription 3 (STAT3) is a key signaling molecule implicated in the regulation of growth and malignant transformation. Constitutive activation of STAT3 has been observed in a number of tumour-derived cell lines, as well as in a wide variety of human malignancies. The present study was conducted to examine p-STAT3 (activated form of STAT3) expression and its association with clinicopathological factors and prognosis in human colorectal adenocarcinomas. Expression of p-STAT3 was immunohistochemically examined in 108 cases of colorectal adenocarcinoma tissue obtained at surgery. and was found in 57.4% of tumours (62 of 108). p-STAT3 immunoreactivity significantly correlated with the depth grading of tumour invasion (p<0.001), lymphatic invasion (p<0.05), Dukes' classification (p<0.05), stage (p<0.001) and prognosis after operation (p<0.001). Expression of p-STAT3 was a marker of poor prognosis in overall survival (p<0.01). Expression of p-STAT3 was detected by Western blot analysis in three colon carcinoma tissue samples obtained at surgery. To our knowledge, this is the first study on the poor prognosis of p-STAT3 in human colorectal adenocarcinomas. These findings suggest that expression of p-STAT3 is an important factor related to tumour invasion and poor prognosis of human colorectal adenocarcinoma.

Adenocarcinoma↗

PubMed2006

Expression of interleukin (IL)-11 and IL-11 receptor in human colorectal adenocarcinoma: IL-11 up-regulation of the invasive and proliferative activity of human colorectal carcinoma cells.

Previous investigations have shown that interleukin (IL)-11/IL-11 receptor alpha-chain (IL-11Ralpha), a member of the PI3K, MAPK and JAK-STAT activating family of cytokines/receptors, correlates with the regulation of tumor progression. In this study, we established the IL-11/IL-11Ralpha expression profile in human colorectal adenocarcinoma (CRC) and clarified its signaling pathway and role in the invasion activity of CRC cell lines. To elucidate the role of IL-11/IL-11Ralpha, we examined 103 cases of CRC and 24 cases of colorectal adenoma by immunohistochemistry. In addition, we investigated the invasive activity of cell signaling pathway of CRC cell lines. The IL-11Ralpha expression was correlated with tumor invasion and lymphatic infiltration (p<0.01, respectively). Recombinant human IL-11 (rhIL-11) promoted the migration and proliferation of HT-29 cells and activated the PI3K and p44/p42 MAPK pathways. Wortmannin, a PI3K inhibitor, and PD98059, a p44/p42 MAPK inhibitor, significantly reduced the promotion of invasion and proliferation activity by rhIL-11, respectively. In summary, the IL-11Ralpha expression was correlated with clinicopathological features and IL-11 promoted the invasion via the PI3K and up-regulated the proliferation via the p44/p42 MAPK in CRC cells. These findings suggested that the IL-11/IL-11R pathway plays an important role in the progression of CRC.

Adenocarcinoma↗

PubMed2005

Antibody to eosinophil cationic protein suppresses dextran sulfate sodium-induced colitis in rats.

AIM: To produce an antibody against rat eosinophil cationic protein (ECP) and to examine the effects of the antibody in rats with dextran sulfate sodium (DSS)-induced colitis. METHODS: An antibody was raised against rat ECP. Rats were treated with 3% DSS in drinking water for 7 d and received the antibody or normal serum. The colons were examined histologically and correlated with clinical symptoms. Immunohistochemistry and Western blot analysis were estimated as a grade of inflammation. RESULTS: The ECP antibody stained the activated eosinophils around the injured crypts in the colonic mucosa. Antibody treatment reduced the severity of colonic ulceration and acute clinical symptoms (diarrhea and/or blood-stained stool). Body weight gain was significantly greater and the colon length was significantly longer in anti-ECP-treated rats than in normal serum-treated rats. Expression of ECP in activated eosinophils was associated with the presence of erosions and inflammation. The number of Ki-67-positive cells in the regenerated surface epithelium increased in anti-ECP-treated rats compared with normal serum-treated rats. Western blot analysis revealed reduced expression of macrophage migration inhibitory factor (MIF) in anti-ECP-treated rats. CONCLUSION: Our results indicate that treatment with ECP antibody, improved DSS-induced colitis in rats, possibly by increasing the regenerative activity of the colonic epithelium and downregulation of the immune response, and suggest that anti-ECP may promote intestinal wound healing in patients with ulcerative colitis (UC).

Amino Acid Sequence↗

PubMed2005

Expression and significance of Tie-1 and Tie-2 receptors, and angiopoietins-1, 2 and 4 in colorectal adenocarcinoma: Immunohistochemical analysis and correlation with clinicopathological factors.

AIM: There is strong evidence that tyrosine kinases are involved in the regulation of tumor progression, cellular growth and differentiation. Recently, many kinds of tyrosine kinase receptors have been reported, among them Tie-1 and Tie-2 receptors constitute a major class. Angiopoietin (Ang)-1 is known as a ligand of Tie-2 tyrosine kinase receptor. The objective of this study was to establish a comprehensive Tie-1 and Tie-2 and Ang-1, 2 and 4 expression profile in human colorectal adenocarcinomas. METHODS: We examined 96 cases of surgically resected human colorectal adenocarcinoma by immunohistochemistry and investigated the statistical correlation between the expressions of Ties and Angs and clinicopathological factors. RESULTS: Among the 96 cases of adenocarcinoma, 87 (90.6%), 92 (95.8%), 83 (86.5%), 89 (92.7%), and 76 cases (79.2%) showed positive staining in the cytoplasm of carcinoma cells for the Tie-1 and Tie-2 and Ang-1, 2 and 4 proteins, respectively. Histologically, the expressions of Ties and Angs were variable. The expressions of Ties and Angs were correlated with several clinicopathological factors, but did not correlate with the presence of lymph node metastasis. Ties and Angs were highly expressed in human colorectal adenocarcinoma cells. CONCLUSION: These findings suggest that the Tie-Ang receptor-ligand complex is one of the factors involved in the cellular differentiation and progression of human colorectal adenocarcinoma.

Adenocarcinoma↗

PubMed2005

Epstein-Barr virus-associated gastric carcinoma in Kazakhstan.

AIM: To investigate the incidence of Epstein-Barr virus-associated gastric cancer (EBV-GC) in Kazakhstan and to compare it with that in Russia, Western and Asian countries in order to evaluate the significance of epidemiopathologic and ethnic factors. METHODS: In situ hybridization (ISH) of EBV-encoded small RNA-1 (EBER-1) was used to identify the presence of EBER-1 signal in 139 formalin-fixed and paraffin-embedded GC tissues from Kazakhstan. RESULTS: EBER-1 expression was observed in the nuclei of 10% of the cases of GC (14/139), but not in the surrounding normal mucosa. The incidence of the diffuse type of EBV-GC was significantly higher in Kazakhstan (14%, 13/91) than that of the intestinal type (2%, 1/48). Furthermore, the incidence was significantly higher in males (14%, 12/89) than in females (3.7%, 2/53) from all countries. The overall incidence of EBV-GC increased from 6.7% in Asian countries to 8.7% in Russia, 10.1% in Kazakhstan and 16% in Western countries. CONCLUSION: Geographical differences in the incidence of EBV-GC may reflect the epidemiologic factors and/or dietary habits independent of histological type and sex.

Adenocarcinoma, Mucinous↗

PubMed2005

Correlation of donor-derived keratinocytes and severity of graft-versus-host disease (GVHD) in epidermis.

Recent reports suggest that bone marrow might serve as a source of skin progenitor cells. Graft-versus-host disease (GVHD) is a systemic disease that involves the skin, the liver, and the gastrointestinal tract, and contributes to transplant-related morbidity and mortality. To evaluate whether donor-derived bone marrow cells participated in its pathophysiology, we correlated the severity of GVHD in skin from sex-mismatched recipients with the percentage of donor-derived keratinocytes using fluorescence in situ hybridization (FISH) for detecting the Y chromosome. Y-positive signals were observed in female epidermis in both keratinocytes and lymphocytes. These results support the notion that donor-derived hematopoietic stem cells may contain pluripotent stem cells. Furthermore, there was a strong correlation between the frequency of Y-positive keratinocytes and the histopathologic grade of GVHD (p = 0.004), as well as with the number of Y-positive lymphocytes infiltrating the epidermis (p = 0.005), suggesting a role for donor-derived keratinocytes in the pathophysiology of GVHD. However, no clusters of Y-positive keratinocytes were found in the epidermis, and no correlation was observed between the number of Y-positive keratinocytes and time course of GVHD after transplantation. We hypothesize that donor-derived stem cells may play a role in the regeneration of damaged keratinocytes in GVHD.

Adult↗

PubMed2005

Sympathetic hyperfunction causes increased sensitivity of the autonomic nervous system to whole-body X irradiation.

Although the etiology of radiation sickness is still unknown, disturbance of the autonomic nervous system is suggested to be a factor. This study was designed to compare the radiosensitivity of spontaneously hypertensive rats possessing sympathetic hyperfunction and control Wistar-Kyoto rats, and to analyze the effects of radiation on the autonomic nervous system in both strains. After a 7.5-Gy dose of whole-body X irradiation, the blood pressure decreased significantly at 8 h and 2 days in the spontaneously hypertensive rats, but not in the Wistar-Kyoto rats. Epinephrine levels in the adrenal gland of spontaneously hypertensive rats decreased at 4, 8 and 24 h, unlike the Wistar-Kyoto rats. Radiation evoked a stronger increase in norepinephrine in the jejunum and colon of spontaneously hypertensive rats than in Wistar-Kyoto rats. Acetylcholine levels in the jejunum of spontaneously hypertensive rats decreased, in contrast to the increase in Wistar-Kyoto rats within 24 h after irradiation. The survival rate of spontaneously hypertensive rats was lower than that of Wistar-Kyoto rats and weight loss, appetite loss and morphological changes in the jejunum were greater in spontaneously hypertensive rats than in Wistar-Kyoto rats after irradiation. These results indicated that X irradiation caused greater activities in autonomic nervous function and severe radiation injury in spontaneously hypertensive rats. Sympathetic hyperfunction may be associated with a higher sensitivity to radiation, including radiation injury and radiation sickness.

Animals↗

PubMed2004

Increased expression of protein C-mannosylation in the aortic vessels of diabetic Zucker rats.

C-Mannosylation is a novel type of glycosylation in proteins. There are several examples of proteins in which the specific motif Trp-X-X-Trp is mannosylated at the first Trp to produce C-mannosylated Trp (CMW). Although C-mannosylation modifies Trp-X-X-Trp, predicted to be a functional motif of various integral proteins such as cytokine receptors, the physiological or pathological relevance of C-mannosylation in the cell is still not known. In this study, to characterize C-mannosylation in biological samples, we generated specific polyclonal antibodies against CMW by using a chemically synthesized CMW as an antigen. Using the antibody, we investigated the effect of hyperglycemic conditions on protein C-mannosylation in cultured cells and diabetic Zucker fatty rats. We found that protein C-mannosylation was increased in macrophage-like RAW264.7 cells under hyperglycemic conditions compared to low-glucose conditions. Furthermore, C-mannosylation was increased in the aortic vessel wall of Zucker fatty rats. Thrombospondin-1 was identified as a protein modified with C-mannosylation, and its expression was also increased in the aortic tissues of Zucker fatty rats. These results indicate that C-mannosylation is increased in specific tissues or cell types under hyperglycemic conditions, suggesting a pathological role for the increased C-mannosylation in the development of diabetic complications.

Amino Acid Motifs↗

PubMed2004

Expression of pituitary tumor transforming gene in human gastric carcinoma.

AIM: Pituitary tumor transforming gene (PTTG1) is overexpressed in a variety of tumors, including carcinomas of the lung, breast, colon, as well as in leukemia, lymphoma and pituitary adenomas. However, there is little information on its expression in gastric carcinoma. We sought to investigate the expression of PTTG1 in gastric carcinoma and to explore the relationship between its expression and clinicopathological factors. METHODS: We studied 75 primary human gastric adenocarcinomas, including 17 mucosal carcinomas, 21 submucosal infiltrative carcinomas, 12 carcinomas invading proprial muscle layers, 6 carcinomas reaching the subserosa, and 19 carcinomas penetrating the serosal surface. Immunohistochemical analysis was performed using paraffin-embedded sections of gastric adenocarcinomas. RESULTS: PTTG1 was expressed heterogeneously in carcinomas. Positive PTTG1 staining was observed in 65.3% of the carcinomas (49 of 75). Its expression did not correlate significantly with either the histological type or the depth of infiltration of the gastric carcinomas. However, a statistical analysis showed significant differences between the primary adenocarcinomas and the associated metastatic lymph nodes. CONCLUSION: The results of this study demonstrate that PTTG1 expression is enhanced in metastatic lymph nodes in comparison to that in primary carcinomas. We suggest that PTTG1 may contribute to lymph node metastases in gastric carcinoma.

Adenocarcinoma↗