Vascular smooth muscle cells and pericytes express MMP-1, MMP-9, TIMP-1 and type I procollagen in inflammatory bowel disease

AIMS: Matrix metalloproteinases (MMPs) are involved in tissue remodelling, which is one of the important aspects of inflammatory disease. To assess the balance between the matrix degradation and production, we analysed the in situ expression of MMP-1, -3, -8 and -9, tissue inhibitor of metalloproteinases (TIMP)-1 and -2, and type I procollagen (PC-I) in inflammatory bowel disease. Methods and results: Immunohistochemistry using frozen sections was performed in 17 patients with ulcerative colitis (UC) and 16 with Crohn's disease (CD). In both UC and CD, MMPs and TIMPs were expressed by inflammatory cells as well as by fibroblastic cells most prominently in actively inflamed areas in ulcer bases, but sparsely in intact inflamed mucosa in both UC and CD. In UC, inflamed mucosa with erosions expressed these substances focally. Fibroblasts also expressed PC-I. We identified that vascular smooth muscle cells of venules in ulcer bases expressed MMP-1 and -9, TIMP-1 and PC-I. These venules also expressed E-selectin, a cell adhesion molecule to facilitate the leucocyte extravasation, and vascular endothelial growth factor (VEGF) receptor 2, consistent with their property of newly formed vessels. CONCLUSIONS: Our results suggest that MMPs are involved in the tissue remodelling, angiogenesis and promotion of leucocyte extravasation in the actively inflamed area in the ulcer base in both UC and CD. MMP-1 expression in the mucosa may be related to the initial step of ulceration in UC. Therapeutic manipulation of extracellular matrix turnover would be an effective therapy to alleviate active inflammation and accelerate ulcer healing.     

Involvement of Krüippel-like factor 6 （KLF6） mutation in the development of nonpolypoid colorectal carcinoma

AIM： To examine Kruppel-like factor 6 （KLF6） mutations in nonpolypoid-type tumors and alterations of K-ras, p53, and B-raf in relation between mutation and morphologic type, particularly nonpolypoid-type colorectal carcinomas.
METHODS： Fifty-five early nonpolypoid colorectal carcinomas were analyzed. Loss of heterozygosity （LOH） of KLF6 and p53 was determined by microsatellite assay. Mutations of KLF6, K-ras, and B-raf were examined by polymerase chain reaction-single-strand conformation polymorphism followed by direct sequencing. In LOH- positive and/or mutation-positive tumors, multiple （4-7） samples in each tumor were microdissected and examined for genetic alterations, p53 expression was evaluated by immunohistochemistry. RESULTS： LOH of KLF6 and p53 was found in 14 of 29 （48.3%） and 14 of 31 （45.2%） tumors, respectively. In tO of the 14 （71.4%） KLF6 LOH-positive tumors and 9 of the 14 （64.3%） p53 LOH-positive tumors, LOH was found in all of the microdissected samples. In 1 of the tO （10.0%） KLF6 LOH-positive tumors, a single missense mutation was identified. K-ras and B-raf mutations were found in 5 of 55 （9.1%） and 6 of 55 （10.9%） tumors, respectively. However, these mutations were detected only in subsets of microdissected tumor samples.
CONCLUSION： These data suggest that KLF6 and p53 mutations are involved in the development of nonpolypoid colorectal carcinoma, whereas K-ras and B-raf mutations are not.     

Triangulating anastomosis using a linear cutter in a colectomy

BACKGROUND/AIMS: We have performed end-to-end anastomosis by the triangulating method using a linear cutter for the reconstruction in colectomy. In this report, we present our technique of triangle anastomosis and its convenience and merits. METHODOLOGY: Patients who underwent end-to-end anastomosis with the triangulating method, or the Gambee procedure, for reconstruction after colon cancer surgery from 1998 to 2003 in our department, were analyzed retrospectively. The anastomosis time and complications were compared in these two groups. RESULTS: The mean anastomosis time was 14.7+/-3.5 minutes, which is 17+/-0.7 shorter than the 31.7+/-4.2 minutes it took for the Gambee anastomosis performed during the same period. There were no significant differences in the incidences and variety of complications. CONCLUSIONS: Triangulating anastomosis using a linear cutter is a safe and easy technique that can be performed in a short amount of time. It is, therefore, considered a useful method for reconstructive surgery for colon cancer.     

Major-nerve schwannomas versus intramuscular schwannomas

Background: A schwannoma is a benign peripheral nerve tumor. Predicting the involvement of a nerve on symptoms or magnetic resonance (MR) findings is crucial to the diagnostic process.

Purpose: To compare symptoms, MR findings, and histological findings between major-nerve schwannomas and intramuscular schwannomas.

Material and Methods: Thirty-four patients with 36 palpable schwannomas (29 major-nerve schwannomas and seven intramuscular schwannomas) surgically excised and proven histologically were retrospectively reviewed.

Results: Frequencies of the Tinel-like sign, split-fat sign, entering and exiting nerve, and low-signal margin indicate the presence of a nerve, and were significantly higher in major-nerve schwannomas than in intramuscular schwannomas. In tumor morphological patterns (target sign, inhomogeneous and homogeneous pattern), there were no significant differences between major-nerve schwannomas and intramuscular schwannomas. Schwannomas showing the target sign histologically tended to be less degenerative. All major-nerve schwannomas and five of the intramuscular schwannomas produced some characteristic symptoms and/or MR findings, but two intramuscular schwannomas did not have any characteristic symptoms and findings.

Conclusion: In major-nerve schwannomas, the Tinel-like sign, split-fat sign, entering and exiting nerve, and low-signal margin are commonly observed and useful for diagnosis. In intramuscular schwannomas, these characteristic findings are less common, which makes diagnosis difficult.     

The effects of fixation,processing and evaluation criteria on immunohistochemical detection of hormone receptors in breast cancer

A task force of the Japanese Breast Cancer Society has proposed a recommendation for adequate evaluation of hormone receptors in routine practice, in order to standardize handling of tissues, staining techniques and scoring systems. As a part of the study, several examinations were conducted to detect the effect of technical problems, including the influence of fixation time and other fixation and processing conditions, on the immunoreactivity for ERalpha. There is little influence of prolonged fixation on the immunoreactivity for ERalpha, except for cases in which particularly over-fixed blocks are used. A delay in the onset of fixation could decrease the immunohistochemical findings of steroid receptors, compared with shorter or longer fixation, and the situation is similar to the fixation of a whole large surgical specimen in formalin in a big bucket. Incomplete fixation might be an important cause of heterogeneiety of immunoreactivity for ERalpha. Manual and automated immunohistochemical (IHC) staining by DAKO (Glostrup, Denmark) and Biogenex (San Ramon, CA) and automated IHC staining by Ventana Medical Systems (Tucson, AZ) each employ different methods. Using a scoring system, in which the proportion of cells stained in each specimen was recorded as 0, less than 1%, 1% or more and less than 10%, and 10% or more, the intermethod variability of those IHC staining methods exhibited substantial multi-rater kappa values concerning the ER and PgR (kappa for ER according to the percentage of positive cells=0.67; PgR=0.72). Concerning intermethod consistency, the scoring system based on the percentage of positive cells was advantageous over other scoring systems, based on the intensity of nuclear staining. Using double staining, patients with ER-positive and HER2-positive tumors can be classified as those with co-expressed tumors and those with differently expressed tumors. As such, the co-expressed tumor might be resistant to antiestrogen therapy in ERalpha-positive and HER2-positive breast cancer and double staining might lead to the development of new therapeutic strategies for hormone and HER2-positive breast cancer.     

Beckwith-Wiedemann syndrome with placental chorangioma due to H19-differentially methylated region hypermethylation: a case report

Beckwith-Wiedemann syndrome (BWS) is a common overgrowth syndrome that involves abdominal wall defects, macroglossia, and gigantism. It is sometimes complicated by placental tumor and polyhydramnios. We report a case of BWS, prenatally diagnosed with ultrasonography. A large and well-circumscribed tumor also existed on the fetal surface of the placenta, which was histologically diagnosed as chorangioma after delivery. Polyhydramnios was obvious and the fetal heart enlarged progressively during pregnancy. Because the biophysical profiling score dropped to 4 points at 33 weeks of gestation, we carried out cesarean section. By epigenetic analysis, H19-differentially methylated region hypermethylation was observed in the placental tumor, normal placental tissue, and cord blood mononuclear cells. This is the first report of BWS with placental tumor due to H19-differentially methylated region hypermethylation.