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11.
Gastric intestinal metaplasia occurs as a pathological condition in the gastric mucosa. To clarify how an intestine-specific homeobox gene, Cdx2, affects the morphogenesis of gastric mucosa, we generated transgenic mice expressing Cdx2 in parietal cells. Until Day 18 after birth, the number of parietal cells inthegastric mucosa of transgenic mice was the same as for their normal littermates. However, at Day 19, we detected several glands in which parietal cells disappeared and the proliferating zone moved from the isthmus to the base of the glands. Thereafter, parietal cells decreased gradually and disappeared at Day 37. All of the gastric mucosal cells, except for enterochromaffin-like (ECL) cells, were completely replaced by intestinal metaplasia, consisting of goblet cells, enteroendocrine cells, and absorptive cells expressing alkaline phosphatase. Pseudopyloric gland metaplasia was also formed. The transgenic mouse is a very useful model for clarifying physiological differentiation of gastric and intestinal cell lineages and analyzing the molecular events from intestinal metaplasia to adenocarcinoma.  相似文献   
12.
Immunocytochemistry of myoepithelial cells in the salivary glands   总被引:3,自引:0,他引:3  
MECs are distributed on the basal aspect of the intercalated duct and acinus of human and rat salivary glands. However, they do not occur in the acinus of rat parotid glands, and sometimes occur in the striated duct of human salivary glands. MECs, as the name implies, have structural features of both epithelial and smooth muscle cells. They contract by autonomic nervous stimulation, and are thought to assist the secretion by compressing and/or reinforcing the underlying parenchyma. MECs can be best observed by immunocytochemistry. There are three types of immunocytochemical markers of MECs in salivary glands. The first type includes smooth muscle protein markers such as -SMA, SMMHC, h-caldesmon and basic calponin, and these are expressed by MECs and the mesenchymal vasculature. The second type is expressed by MECs and the duct cells and includes keratins 14, 5 and 17, 1β1 integrin, and metallothionein. Vimentin is the third type and, in addition to MECs, is expressed by the mesenchymal cells and some duct cells. The same three types of markers are used for studying the developing gland.

Development of MECs starts after the establishment of an extensively branched system of cellular cords each of which terminates as a spherical cell mass, a terminal bud. The pluripotent stem cell generates the acinar progenitor in the terminal bud and the ductal progenitor in the cellular cord. The acinar progenitor differentiates into MECs, acinar cells and intercalated duct cells, whereas the ductal progenitor differentiates into the striated and excretory duct cells. Both in the terminal bud and in the cellular cord, the immediate precursors of all types of the epithelial cells appear to express vimentin. The first identifiable MECs are seen at the periphery of the terminal bud or the immature acinus (the direct progeny of the terminal bud) as somewhat flattened cells with a single cilium projecting toward them. They express vimentin and later -SMA and basic calponin. At the next developmental stage, MECs acquire cytoplasmic microfilaments and plasmalemmal caveolae but not as much as in the mature cell. They express SMMHC and, inconsistently, K14. This protein is consistently expressed in the mature cell. K14 is expressed by duct cells, and vimentin is expressed by both mesenchymal and epithelial cells.

After development, the acinar progenitor and the ductal progenitor appear to reside in the acinus/intercalated duct and the larger ducts, respectively, and to contribute to the tissue homeostasis. Under unusual conditions such as massive parenchymal destruction, the acinar progenitor contributes to the maintenance of the larger ducts that result in the occurrence of striated ducts with MECs. The acinar progenitor is the origin of salivary gland tumors containing MECs. MECs in salivary gland tumors are best identified by immunocytochemistry for -SMA. There are significant numbers of cells related to luminal tumor cells in the non-luminal tumor cells that have been believed to be neoplastic MECs.  相似文献   

13.
Primary osteogenic sarcoma of the breast is a rare neoplasm, diagnosed mainly by pathohistological and immunohistochemical analysis.We hereby present a case of primary osteogenic sarcoma in the right breast of a 62-year-old woman with synchronous appearance of an invasive ductal carcinoma. Clinical findings are manifested with two separate painless formations 2.5 cm/2 cm and 1.5 cm/1 cm in size, located on the border of the upper and lower lateral quadrant of the right breast. No axillary lymphadenopathy was diagnosed. The pathohistological and immunohistochemistry findings of both tumors revealed a synchronous manifestation of two distinct neoplasms – epithelial and non-epithelial. Multimodality treatment consisted of Patey''s radical mastectomy; 3 cycles of adjuvant chemotherapy; postoperative 50 Gy radiotherapy to the chest wall followed by additional 3 cycles of chemotherapy and anti-estrogen hormonotherapy.Due to the rarity of osteogenic mammary sarcoma, even more so in a combination with epithelial breast tumors, its clinical features are unclear and optimal treatment remains controversial. Considering the poor prognosis of the combination of both malignomas, we discuss a number of diagnostic and therapeutic issues.  相似文献   
14.
Cell motility is controlled by the dynamic cytoskeleton and its related proteins, such as members of the ezrin/radixin/moesin (ERM) family, which act as signalling molecules inducing cytoskeleton remodelling. Although ERM proteins have been identified as important factors in various malignancies, functional redundancy between these proteins has hindered the dissection of their individual contribution. The aim of the present study was to analyse the functional role of moesin in pancreatic malignancies. Cancer cells of different malignant lesions of human and transgenic mice pancreata were evaluated by immunohistochemistry. For functional analysis, cell growth, adhesion and invasion assays were carried out after transient and stable knock‐down of moesin expression in pancreatic cancer cells. In vivo tumourigenicity was determined using orthotopic and metastatic mouse tumour models. We now show that moesin knock‐down increases migration, invasion and metastasis and influences extracellular matrix organization of pancreatic cancer. Moesin‐regulated migratory activities of pancreatic cancer cells were in part promoted through cellular translocation of β‐catenin, and re‐distribution and organization of the cytoskeleton. Analysis of human and different transgenic mouse pancreatic cancers demonstrated that moesin is a phenotypic marker for anaplastic carcinoma, suggesting that this ERM protein plays a specific role in pancreatic carcinogenesis.  相似文献   
15.
The aim was to determine the association between the subtypes of borderline nuclear changes (BNC) in cervical smears and high-grade cervical intraepithelial neoplasia (HCIN). BNC was reported in 23236 smears received in our laboratory over a 7-year period, 3278 patients were referred for colposcopy. Analysis was restricted to 2007 cases, which fitted the criteria of: (1). consistent subtyping of borderline change and (2). cervical histology result within 12 months of the last abnormal smear. BNC was reported in six categories and correlated with histology. Atypia bordering on dyskaryosis, atypical metaplastic cells and endocervical atypia, were associated with HCIN in 25%, 25.4% and 23.8% of cases, respectively. Dyskeratosis and koilocytotic atypia were associated with HCIN in 19.2% and 13.7% of cases, respectively. Some subtypes of borderline change are more frequently associated with HCIN. The difference is not sufficient to dictate clinical management.  相似文献   
16.
BACKGROUND INFORMATION: Prolonged copper deprivation in rats followed by refeeding with a normal diet has previously been used to induce the appearance of hepatocyte-like cells in the pancreas, but the effects on islet size and morphology have not been determined. RESULTS: In the present study we investigated the distribution of pancreatic alpha- and beta-cells and of hepatocytes in adult rats fed a copper-deficient diet followed by refeeding with a normal diet. Immunohistochemical staining for insulin and glucagon showed that the islets of the copper-deficient group were up to 2.4 times larger in mass compared with controls. The islets were disorganized, with alpha-cells found in multiple layers at the periphery of the islet and sometimes deep in the core. Isolated alpha- and beta-cells were also found in increased numbers in the ductular system. Copper deprivation caused almost complete ablation of the acinar cells, and refeeding induced adipogenesis, acinar regeneration and hepatocyte-like cells. Ductular proliferation and nerve hyperplasia were also present. The hepatocytes tended to be associated with islets or with ducts, rather than with residual pancreatic exocrine tissue. CONCLUSIONS: These data show that copper deficiency in rats, as well as inducing the appearance of hepatocytes, is capable of causing islet hyperplasia.  相似文献   
17.
We assessed the co-expression of cell cycle-related biomarkers in a series of 121 consecutive cases of high-grade ductal carcinoma in situ (DCIS), pure or associated with invasive carcinoma, and their associations with the different immunoprofiles of DCIS. Cases were identified from the histopathology files of the Breast Pathology Laboratory, Federal University of Minas Gerais, Brazil, from 2003 to 2008. The expression of estrogen receptor, progesterone receptor, HER2 overexpression, cytokeratin 5, epidermal growth factor receptor 1, cyclooxygenase-2, p16 and Ki67 were assessed. Tumors were placed into five subgroups according to their immunohistochemical profile: luminal A, luminal B, HER2, basal-like and “not classified”. We found that the basal phenotype was associated with a higher frequency of p16-positive cases (83%) and the luminal A phenotype showed a higher frequency of p16-negative cases (93%; p=0.000). The association of biomarkers p16+/Ki67+/COX2+ was expressed in 02/06 cases (33.3%) of the basal phenotype but in only 01/70 cases (1.4%) of the luminal A phenotype (p=0.01). The co-expression of p16+/Ki67+/COX2- was associated with a basal phenotype (p=0.004). P16 expression, p16+/Ki67+/COX2+ and p16+/Ki67+/COX2- co-expression showed significant associations with the basal phenotype and these profiles could be used to guide more aggressive treatment strategies in patients with high-grade DCIS.  相似文献   
18.

Background

Gastric cancer exhibits familial clustering, and gastric cancer familial relatives (GCF) tend to present with corpus-predominant gastritis and precancerous lesions as SPEM or IM after H. pylori infection. The study determined whether the children of gastric cancer patients (GCA) had genomic single nucleotide polymorphisms (SNPs) predisposed to the gastric precancerous lesions as spasmolytic polypeptide-expressing metaplasia (SPEM) or intestinal metaplasia (IM).

Results

There were 389 family relatives of 193 non-cardiac GCA and 173 duodenal ulcer patients (DU), received blood sampling for DNA collection. The differences of the risk alleles of SNPs in the ITGA5, ITGB1, IL-10, COX-2, RUNX3, and TFF2 genes were compared between 195 children of GCA and 143 DU. The children of GCA had higher allele frequencies of ITGA5-1160 T-carrier (P = 0.006, OR[95% CI] = 2.2[1.2-4]), ITGB1-1949 A-carrier (P = 0.047; OR[95% CI] = 2.8[1.4-5.3]), ITGB1 + 31804 C-carrier (P = 0.013; OR[95% CI] = 4.7[1.7-13.0]), IL-10-592 AA (P = 0.014; OR[95% CI] = 2.3[1.4-4.0]) and COX-2-1195 G-carrier (P = 0.019; OR[95% CI] = 1.7[0.9-3.2]) than DU. The combined genotype with ITGA5-1160/ITGB1-1949/ITGB1 + 31804 as T/A/C carriers and COX-2-1195/IL-10-592 as G-carrier/AA was more prevalent in the children of GCA than in DU (P < 1×10−4), and predisposed with a 5.3-fold risk of getting SPEM in the H. pylori-infected children of GCA (P = 0.016). Such risk of getting SPEM increased to 112 folds, if combined with RUNX3 + 492/TFF2-308 as A-carrier/CC in this limited study scale (P = 1×10−4).

Conclusions

The SNPs of ITGA5-1160/ITGB1-1949/ ITGB1 + 31804 as T/A/C carriers and COX-2-1195/IL-10-592 as G-carrier/AA, or more specific to combine RUNX3 + 492/TFF2-308 as A-carrier/CC shall be host factor predisposing to gastric cancer during H. pylori infection, and serve as marker to identify high-risk subjects for H. pylori eradication.

Electronic supplementary material

The online version of this article (doi:10.1186/s12929-015-0121-7) contains supplementary material, which is available to authorized users.  相似文献   
19.
T. Kawasaki, S. Nakamura, G. Sakamoto, T. Kondo, H. Tsunoda‐Shimizu, Y. Ishii, T. Nakazawa, K. Mochizuki, T. Yamane, M. Inoue, S. Inoue and R. Katoh
Neuroendocrine ductal carcinoma in situ of the breast: cytological features in 32 cases Objective: The purpose of this study was to clarify the cytological features of neuroendocrine ductal carcinoma in situ (NE‐DCIS) of the breast. Methods: We analysed the cytopathological findings in 22 fine needle aspiration (FNA) smears and 17 nipple discharge smears obtained from 32 Japanese patients with NE‐DCIS. Results: The background of the FNA smears was clear (59%), mucoid (23%), haemorrhagic (14%) or necrotic (5%). Most of the FNA smears (95%) showed high cellularity. Characteristically, NE‐DCIS cells were loosely arranged in three‐dimensional solid clusters or singly dispersed. Well‐developed vascular cores with or without malignant cells were occasionally recognized. The tumour cells were polygonal or spindle‐shaped with a fine granular, abundant cytoplasm. Nuclei with finely granular chromatin were round or oval and often eccentrically located (plasmacytoid appearance). Mitotic figures were infrequent. Nuclear grade was estimated to be low in 86%. Most nipple discharge smears had fairly low cellularity with poorly preserved cell clusters in a markedly haemorrhagic background, although two (12%) were extremely cellular with cytological characteristics similar to those of the FNA smears. Pre‐operative cytological malignant diagnoses were made in 42% of FNA smears and 0% of nipple discharge smears. Immunohistochemistry for neuroendocrine markers (chromogranin A and synaptophysin) confirmed the neuroendocrine nature of this tumour in adequate cytological specimens. Conclusions: NE‐DCIS has distinctive cytological features and can therefore be diagnosed as a neuroendocrine tumour in most FNAs and some nipple discharge smears by cytological examination employing immunohistochemical techniques. We emphasize that a breast lesion with these features may be in situ and not invasive, and also that there is a risk of under‐diagnosis.  相似文献   
20.
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