Differential expression of CD34 in normal colorectal tissue, peritumoral inflammatory tissue, and tumour stroma

AIMS: To investigate the role of CD34 positive stromal cells, namely dendritic interstitial cells, in the desmoplastic stroma formation of malignant epithelial neoplasms the distribution of CD34 positive stromal cells was examined in human colorectal adenocarcinomas, peritumoral inflammatory tissue, and normal tissue. METHODS: Forty one surgically resected human colorectal adenocarcinomas and their corresponding peritumoral inflammatory and normal tissues were examined. To distinguish CD34 positive stromal cells from vascular endothelial cells, immunostaining for both CD34 and CD31 was performed. The distribution of myofibroblasts was also analysed immunohistochemically, and double staining with CD34 and alpha smooth muscle actin (ASMA) was performed. RESULTS: Most of the stromal cells in the normal colorectal submucosa, muscularis propria, subserosa, and perirectal tissue were positive for CD34. In contrast, the peritumoral inflammatory tissue and the tumour stroma had no CD34 positive stromal cells. The distribution of myofibroblasts was almost the same as in the aforementioned series. No stromal cells double positive for CD34 and ASMA were detected in the peritumoral inflammatory tissues. CONCLUSIONS: Most stromal fibroblasts are CD34 positive stromal cells (dendritic interstitial cells). In colorectal adenocarcinomas, a lack of CD34 expression in stromal cells is associated with desmoplastic reaction.     

High molecular weight caldesmon positive stromal cells in the capsule of hepatocellular carcinomas

AIMS: To investigate the smooth muscle nature of the stromal cells in the capsule of hepatocellular carcinomas. METHODS: Immunohistochemical analysis using monoclonal antibody to high molecular weight caldesmon (HCD), a highly specific marker for smooth muscle cells, was performed in 33 encapsulated hepatocellular carcinomas and adjacent hepatic tissues. RESULTS: HCD positive stromal cells were detected in the capsule of 21 of the 33 hepatocellular carcinomas examined. CONCLUSIONS: The capsule of hepatocellular carcinomas contains smooth muscle cells.     

Developmental expression of high molecular weight tropomyosin isoforms in Mesocestoides corti

Tropomyosins are a family of actin-binding proteins with diverse roles in actin filament function. One of the best characterized roles is the regulation of muscle contraction. Tropomyosin isoforms can be generated from different genes, and from alternative promoters and alternative splicing from the same gene. In this work, we have isolated sequences for tropomyosin isoforms from the cestode Mesocestoides corti, and searched for tropomyosin genes and isoforms in other flatworms. Two genes are conserved in the cestodes M. corti and Echinococcus multilocularis, and in the trematode Schistosoma mansoni. Both genes have the same structure, and each gene gives rise to at least two different isoforms, a high molecular weight (HMW) and a low molecular weight (LMW) one. Because most exons are duplicated and spliced in a mutually exclusive fashion, isoforms from one gene only share one exon and are highly divergent. The gene duplication preceded the divergence of neodermatans and the planarian Schmidtea mediterranea. Further duplications occurred in Schmidtea, coupled to the selective loss of duplicated exons, resulting in genes that only code for HMW or LMW isoforms. A polyclonal antibody raised against a HMW tropomyosin from Echinococcus granulosus was demonstrated to specifically recognize HMW tropomyosin isoforms of M. corti, and used to study their expression during segmentation. HMW tropomyosins are expressed in muscle layers, with very low or absent levels in other tissues. No expression of HMW tropomyosins is present in early or late genital primordia, and expression only begins once muscle fibers develop in the genital ducts. Therefore, HMW tropomyosins are markers for the development of muscles during the final differentiation of genital primordia.     

Elevated nuclear maspin expression is associated with microsatellite instability and high tumour grade in colorectal cancer

Maspin, a member of the serpin family, has been reported to suppress metastasis and angiogenesis in breast and prostate cancers. Overexpression of maspin was associated with adverse prognostic features in several other tumours. In this study, expression of maspin was analysed in 41 colorectal carcinomas with high-frequency microsatellite instability (MSI-H) and 159 microsatellite stable colorectal cancers (MSS/MSI-L) by immunohistochemistry (IHC) and partly by relative quantitative real-time RT-PCR and western blot analyses. Significant upregulation of maspin expression was found in MSI-H tumours compared to both MSS/MSI-L tumours and matched benign colonic mucosa. Increased maspin expression was also found in three MSI-H colon cancer cell lines, but not in three MSS colon cancer cell lines by RT-PCR and western blot analyses. Regulation of maspin expression depended on promoter methylation as tissue specimens and cell lines expressing maspin showed unmethylated maspin promoters, whereas promoter hypermethylation was found in specimens with loss of maspin expression. Intense nuclear maspin immunostaining was seen specifically in MSI-H tumours (p = 0.013), de-differentiated tumours (p = 0.006), and at the invasion front. These findings provide new insights into the role of maspin in colorectal cancer progression and may be useful for diagnosis and treatment strategies.     

High molecular weight caldesmon positive stromal cells in the capsule of thyroid follicular tumours and tumour-like lesions

AIMS: To investigate the smooth muscle nature of the spindle stromal cells in the capsule of thyroid tumours and tumour-like lesions. METHODS: Immunostaining for high molecular weight caldesmon (HCD), a highly specific marker for smooth muscle differentiation, was performed in 70 primary thyroid tumours and tumour-like lesions (21 hyperplastic nodules, 29 follicular adenomas, five minimally invasive follicular carcinomas, six widely invasive follicular carcinomas, and nine encapsulated papillary carcinomas). RESULTS: HCD positive stromal cells (HCD+ cells) were detected in the capsule of 20 of the 21 hyperplastic nodules, and all of the 29 follicular adenomas and five minimally invasive follicular carcinomas, whereas HCD+ cells were seen in the capsule of only four of the six widely invasive follicular carcinomas and no HCD+ cells were seen in the capsule of the nine encapsulated papillary carcinomas examined. CONCLUSIONS: The presence of HCD+ cells in the capsule is characteristic of thyroid follicular tumours and tumour-like lesions. The stromal cells in the capsule of thyroid follicular tumours and tumour-like lesions are different from those of encapsulated papillary carcinoma.     

肌纤维母细胞及在肿瘤间质中激活的纤维母细胞

背景：肌纤维母细胞从1971年被发现以来一直是一个充满争议的课题,近年的研究认识到,该细胞在肿瘤的发生、发展过程中可能起着重要作用。 目的：阐述肌纤维母细胞的生物学特征,以及肿瘤间质纤维母细胞在肿瘤的生长、侵袭方面的作用。 方法：由第一作者检索万方数据库及Pubmed数据库中1990-01/2010-01与肌纤维母细胞相关的文献,在标题和摘要中以“肌纤维母细胞;肿瘤;转化生长因子;侵袭性”或“myofibroblast;tumor;TGF-β;aggressiveness”为检索词进行检索。选择内容与肌纤维母细胞及肿瘤间质纤维母细胞相关的文章,同一领域文献则选择近期发表或发表在权威杂志文章。初检得到116篇文献,根据纳入标准选择41篇文章进行综述。 结果与结论：肌纤维母细胞具有平滑肌和纤维母细胞的特征,肿瘤间质肌纤维母细胞是癌细胞衍生的细胞因子调控成纤维细胞转化而来,通过直接刺激癌细胞的增殖和生存来促进肿瘤生长,并通过水解细胞基质和刺激肿瘤细胞运动来发生侵袭。肌纤维母细胞的出现有助于肿瘤的早期诊断及探索肿瘤治疗的新途径。     

The demonstration of pericryptal fibroblasts in background mucosa and dysplasia complicating ulcerative colitis

The demonstration of pericryptal fibroblasts in background mucosa and dysplasia in ulcerative colitis was investigated by immunohistochemistry using monoclonal antibody for alpha-smooth muscle actin. Pericryptal fibroblasts were reduced in 18 (26%) of the 68 sections of non-dysplastic mucosa. The reduction was significantly correlated with goblet cell depletion and villous change. Pericryptal fibroblasts were more frequently reduced (50%) in dysplastic mucosa, the reduction being greater in villous than in non-villous dysplasia. Pericryptal fibroblast development was not related to grade of dysplasia (low or high-grade), distance from carcinoma (adjacent to or distant from carcinoma) or growth pattern (polypoid or non-polypoid). These findings suggest that: 1 reduction of pericryptal fibroblasts in background mucosa may relate to the development of dysplasia in ulcerative colitis, 2 reduction of pericryptal fibroblasts in villous regeneration, analogous to that in dysplasia, reinforces the hypothesis that villous change may be a marker for risk of development of carcinoma in ulcerative colitis.     

Differential CXC receptor expression in colorectal carcinomas

In this study, we aimed to assess the expression profile of chemokine receptors CXCR1–4 in inflammatory and malignant colorectal diseases and corresponding hepatic metastases of synchronous and metachronous origin to elucidate their role in colorectal cancer (CRC) progression and metastasis. Chemokine receptor expression was assessed by quantitative real-time PCR, immunohistochemistry (IHC) and Western blot analysis in resection specimens from patients with ulcerative colitis (UC, n  = 25), colorectal adenomas (CRA, n  = 8), different stages of CRC ( n  = 48) as well as colorectal liver metastases (CRLM) along with their corresponding primary colorectal tumours ( n  = 16). While none of the chemokine receptors were significantly upregulated or downregulated in UC or CRA tissues, CXC receptors 1, 2 and 4 demonstrated a significant increase in expression in all tumour stages of CRC specimens with CXCR4 correlating with tumour grading ( P  < 0.05). On the other hand, CXCR3 showed no significant upregulation in either tumour stage, but significant overexpression in CRLM. While CXCR4 demonstrated significant upregulation in both tumour entities, IHC analysis revealed that the predominate cell type expressing CXCR4 in CRC is represented by tumour cells, whereas in CRLM the majority of positive CXCR4 signals is due to hepatocytes along the tumour invasion front. In conclusion, our findings show a very differential expression pattern of the four receptors in colorectal carcinomas and their corresponding liver metastases with prominent expression profiles that indicate a potential role in the pathogenesis of CRC.     

Characterization of high molecular weight novolak

High molecular weight novolaks were prepared by polycondensation of phenol with paraform-aldehyde in acetic acid. The novolak contains soluble, high molecular weight fractions (M _w ≥ 10⁶). The Θ-temperature of the acetylated novolak was determined in 2-ethoxyethanol according to the Shultz-Flory method. The solution viscosity of acetylated and deacetylated novolaks in THF at 25°C and in a Θ-solvent (2-ethoxyethanol at 105°C) was measured, and the molecular dimension in solution was estimated from the parameters of the Mark-Houwink-Sakurada equation. The exponent of 0.24 in THF (good solvent) for acetylated novolak is equal to that in the Θ-solvent. This suggests that the conformation of the novolak is compact like a sphere both in the good and the Θ-solvent. The theoretical value of the exponent in the MHS equation for highly branched polymers is between 0.2 and 0.25 in a Θ-solvent. The exponent for acetylated novolak in the Θ-solvent is close to this value. It is suggested that the acetylated novolak behaves like a highly branched polymer in a Θ-solvent. The ¹³C NMR spectrum of novolak confirms that the novolak molecule is a highly branched polymer.     

Association of trypsin expression with tumour progression and matrilysin expression in human colorectal cancer

Overexpression of the matrix serine protease (MSP) trypsin has been implicated in tumour growth, invasion, and metastasis. The objective of this study was to clarify the clinicopathological and prognostic significance of trypsin expression in colorectal cancer. This study analysed the association between immunohistochemically detected trypsin expression in colorectal cancer and clinicopathological characteristics, and investigated whether trypsin is a predictor of recurrence and/or survival. Trypsin immunoreactivity was more intense at the invasive front than in the superficial part of the tumour. Sections with immunostaining signals in more than 30% of carcinoma cells at the invasive front, which were observed in 48 cases (48%), were judged to be positive for trypsin. Trypsin positivity was significantly correlated with depth of invasion, lymphatic and venous invasion, lymph node and distant metastasis, advanced pathological tumour-node-metastasis (TNM) stage, and recurrence. Patients with trypsin-positive carcinoma had significantly shorter overall and disease-free survival periods than did those with trypsin-negative carcinoma. Trypsin retained its significant predictive value for overall and disease-free survival in multivariate analysis that included conventional clinicopathological factors. It is well known that trypsin activates matrilysin (matrix metalloproteinase-7), which plays an important role in colorectal cancer progression. Patients with concordant overexpression of trypsin and matrilysin at the invasive front, in which they were often co-localized, had the worst prognosis. Trypsinogen-1-transfected HCT116 colon cancer cells showed not only trypsin activity, but also active matrilysin activity and were more invasive in vitro than mock-transfected HCT116 cells. These results suggest that trypsin plays a key role in the progression of colorectal cancer. Detection of trypsin expression as well as matrilysin is useful for the prediction of recurrence in and poor prognosis of colorectal cancer patients.     

Hydrolytic degradation of electron beam irradiated high molecular weight and non-irradiated moderate molecular weight PLLA

The purpose of this study is to examine the hydrolytic degradation of electron beam irradiated ring-opening polymerized (ROP) poly(l-lactide) (PLLA-ir) and non-irradiated melt polycondensation polymerized poly(l-lactic acid) (PLLA-pc). It was observed that irradiation increases the hydrolytic degradation rate constant for ROP PLLA. This was due to a more hydrophilic PLLA-ir, as a result of irradiation. The degradation rate constants (k) of PLLA-ir samples were also found to be similar, regardless of the radiation dose, and an empirically formulated equation relating hydrolytic degradation time span to radiation dose was derived. The k value for PLLA-pc was observed to be lower than that for PLLA-ir, though the latter had a higher molecular weight. This was due to the difference in degradation mechanism, in which PLLA-ir undergoes end group scission, through a back- biting mechanism, during hydrolysis and thus a faster hydrolysis rate. Electron beam irradiation, though accelerates the degradation of PLLA, has been shown to be useful in accurately controlling the hydrolytic time span of PLLA. This method of controlling the hydrolytic degradation time was by far an easier task than through melt polycondensation polymerization. This would allow PLLA to be used for drug delivery purposes or as a temporary implant that requires a moderate time span (3-6 months).     

Mammary fibroadenoma and some phyllodes tumour stroma are composed of CD34+ fibroblasts and factor XIIIa+ dendrophages

Fibroadenomas and mammary phyllodes tumour arise by proliferation of mammary stroma and epithelial elements. However, it is the stromal element that determines the biology of these biphasic tumours. Normal mammary stroma, like most collagenous connective tissue, contains resident populations of CD34+ dendritic interstitial cells and scattered factor XIIIa+ collagen-associated dendrophages. Actin + myofibroblasts are usually absent from mammary stroma in non-disease states. To determine whether CD34+ and factor XIIIa+ cells proliferate in fibroadenomas and phyllodes tumours, and to study myofibroblastic differentiation in these lesions, we examined 19 fibroadenomas in 14 patients along with five low grade and two high grade phyllodes tumours. We employed antibodies against the human progenitor cell antigen CD34, coagulation factor XIIIa and HHF-35 actin. In three fibroadenomas and two phyllodes tumours, we used Ki-67 antigen to study cell proliferation and oestrogen and progesterone receptors to study possible hormonal influence on stromal cells. In all fibroadenomas, CD34 strongly stained interlobular, pericanalicular and intracanalicular fibroblasts with collagenous and/or myxoid features. Four low grade phyllodes tumours also had CD34+ fibroblasts as did one high grade tumour. Actin reactivity varied and was most pronounced in six fibroadenomas resembling the so-called cellular variant, while seven regular fibroadenomas had no actin + stromal cells and six had only focal and weak actin + stromal cells. Factor XIIIa+ cells were prominently admixed in the stroma of all tumours studied comprising from 5% to 20% in fibroadenomas and, focally, up to 50% in phyllodes tumours. Oestrogen and progesterone receptors were expressed only in glandular elements. Ki-67 index in stromal cells was 1% to 3% in fibroadenoma, 10% to 20% in low grade, and 20% to 40% in high grade phyllodes tumour. We conclude that fibroadenomas and some phyllodes tumours are composed of CD34+ fibroblasts that show varying myxoid, collagenous or myofibroblastic differentiation. The fibroblasts are accompanied by a subset of dendritic histiocytes that express factor XIIIa. Fibroadenoma variants show prominent collagenous actin + myofibroblastic differentiation of CD34+ stromal cells, sometimes with a gradient of CD34 down-regulation. Fine-needle or limited stereotactic core biopsy of these biphasic tumours, if they yield only stromal cells, must be distinguished from other CD34+ stromal tumours. Increased factor XIIIa+ dendrophage populations were seen in phyllodes tumours, especially in two high grade tumours that had malignant fibrous histiocytoma-like features, suggesting clonal evolution toward the fibrohistiocytic final pathway. Further study of CD34 and factor XIIIa + mammary stromal cells in larger numbers of phyllodes tumours might ascertain whether increasing factor XIIIa reactivity correlates with differentiation and increased tumour aggressiveness.     

Benign salivary gland-type tumors of the bronchus: expression of high molecular weight cytokeratins

Primary lung tumors showing features of salivary gland-type neoplasms are extremely rare, and their immunohistochemical profile has been seldom studied. We report two cases of bronchial pleomorphic and mucous gland adenomas and study the expression of markers such as TTF-1 and high molecular weight keratins in these tumors. Both tumors were endobronchial. The pleomorphic adenoma also had a well-circumscribed parenchymal component, with a biphasic morphology composed of epithelial and myoepithelial cells in a background of myxoid and hyaline stroma. The mucous gland adenoma displayed papillary and dilated glandular structures. In both cases, epithelial cells showed strong and diffuse cytoplasmic staining with high molecular weight cytokeratins (cytokeratin 5/6 and keratin 903), and lacked TTF-1 expression. This immunoprofile provides useful clues for the histogenesis of pulmonary benign salivary gland-type adenomas and helps in distinguishing them from primary adenocarcinomas in small biopsy specimens.     

Relationship between CD44 expression and cell proliferation in epithelium and stroma of colorectal neoplasms.

The cell surface glycoprotein CD44 is expressed primarily in the region of cell replication in the lower crypt epithelium of colorectal mucosa, and its expression is markedly increased in colorectal neoplasms, suggesting that expression is linked to proliferation. The association between CD44 expression and replication in individual cells was therefore analyzed by double-label immunohistochemistry for CD44 and the cell-cycle-dependent protein proliferating cell nuclear antigen (PCNA). Enhanced expression of CD44 in colorectal neoplasms occurred not only in epithelial cells but also in stromal cells, including lymphocytes and macrophages. On a topographical basis, the cellular localization of CD44 and PCNA were commonly different. Quantitatively, in all cell types studied (epithelial cells and stroma of colorectal mucosa, adenomas, and carcinomas) PCNA was present most frequently in cells lacking CD44. Statistical analysis by logistic regression models indicated that cells negative for CD44 had a higher probability of being positive for PCNA than did cells positive for CD44 (P < 0.001). These data suggest that the enhanced level of CD44 in colorectal neoplasms is asynchronous with cell replication and reflects mechanisms that act on nonproliferative stromal lymphocytes and other mononuclear cells as well as the epithelial cells.     

Formation of high molecular weight polythiiranes in aqueous-organic media

The influence of water on the polymerization of thiirane and 2-methylthiirane with CdCO₃ was studied. The polymerization process takes place only when a large interface monomer-water is formed. This is achieved by the presence of an amount of water in the reaction mixture which is comparable with that of the monomer. The polarity of the solvent does not influence the rate of formation of poly(2-methylthiirane). The polymerization is carried out in the mass of monomer or in the presence of an alcohol and a solvent not miscible with water.     

Epsin3在结直肠癌中的差异表达及生物信息学分析

目的 探讨介导内吞作用的衔接蛋白epsin 3（EPN3）在结直肠癌中的表达及意义,为深入研究EPN3的调控模式提供实验依据。 方法 分别运用GEPIA和GEDS数据库分析EPN3在结直肠癌组织和细胞中的表达情况,并通过SMART和cBioPortal数据库分析EPN3基因甲基化和拷贝数变异与其表达水平的关系;利用Metascape数据库对EPN3相关的共表达基因集进行GO富集和通路分析;运用BioPlex蛋白互作数据库分析EPN3在HCT116细胞中的蛋白作用网络。为了对EPN3进一步验证,我们收集13对结直肠癌癌旁组织和癌组织标本,用Real-time PCR检测EPN3 mRNA表达;并通过敲减EPN3观察其对肿瘤细胞增殖、集落形成和迁移能力的影响。 结果 GEPIA、GEDS、SMART和cBioPortal等数据库分析显示,EPN3在结直肠肿瘤组织中高表达(P<0.01)。其表达水平与甲基化和拷贝数变异相关。EPN3相关基因的富集结果显示主要与细胞黏附相关。EPN3与UBB、CCDC130、TNFAIP1、PHGDH、EPN2等构成的蛋白相对作用网络与蛋白泛素化有关。Real-time PCR结果显示,EPN3在癌组织中高表达(P<0.05)。通过沉默EPN3可以抑制HCT116和HT29细胞的增殖、集落形成和迁移能力。 结论 EPN3在结直肠癌组织中高表达,且与细胞黏附和蛋白泛素化等生物学过程有关,敲低EPN3可抑制结直肠癌细胞系HCT116和HT29的增殖、集落形成和迁移等过程。