Increased expression of dermatopontin mRNA in the infarct zone of experimentally induced myocardial infarction in rats: comparison with decorin and type I collagen mRNAs

Objectives: Dermatopontin, a 22 kDa extracellular matrix (ECM) protein, has been shown to interact with other ECM components, especially decorin, and to regulate ECM formation. We examined dermatopontin mRNA expression in the myocardial infarct zone. Methods: The cDNA encoding the rat dermatopontin was cloned by RT-PCR based on screening results from the Expressed Sequence Tag™ database. The dermatopontin mRNA expression was examined in the infarct zone after experimentally induced myocardial infarction in rats by the methods of Northern blotting and in situ hybridization. The expression of dermatopontin mRNA was compared to that of decorin and type I collagen mRNAs. Results: The isolated clone contained a 609 bp cDNA insert containing a complete open reading frame encoding 202 amino acids. The rat dermatopontin cDNA showed high homology to human and mouse counterparts (>96 %). Northern blotting demonstrated that dermatopontin mRNA expression did not markedly increase on day 2, but was increased on days 7, 14 and 28 by 2.4-, 4.1- and 4.2-fold, respectively, compared to that in preligation hearts. Dermatopontin mRNA expression was regulated almost in parallel with decorin mRNA expression. In situ hybridization demonstrated mRNA signals for dermatopontin in macrophages and spindle-shaped mesenchymal cells (fibroblasts and myofibroblasts) located in the infarct interior zone around infarcted necrotic tissue on day 7. Coexpression of dermatopontin mRNA with decorin and type I collagen mRNAs was observed in spindle-shaped mesenchymal cells. Conclusions: The present results demonstrated the time-dependent increase in the expression of dermatopontin mRNA in parallel with that of decorin mRNA in the infarct zone. Coexpression of dermatopontin mRNA with decorin and type I collagen mRNAs suggests that dermatopontin plays a role in ECM (fibrillar collagen matrix) reformation in the infarct along with decorin and type I collagen. Received: 7 March 2002, Returned for revision: 8 April 2002, Revision received: 16 May 2002, Accepted: 3 June 2002 Correspondence to: S. Kusachi, MD     

Perindopril effect on uncoupling protein and energy metabolism in failing rat hearts

Uncoupling proteins, inner mitochondrial membrane proton transporters, are important for regulating myocardial energy efficiency. We investigated the effects of the ACE inhibitor perindopril on cardiac performance, myocardial energy efficiency, and uncoupling protein expression in an aortic regurgitation rat model. Twenty male Sprague-Dawley rats, in which aortic regurgitation was produced, were divided into untreated and perindopril-treated (5 mg x kg(-1) x d(-1)) rats. The treatments were initiated 3 days after operation. Ten control rats were sham-operated. Measurements of blood pressure and echocardiography were repeated before and 100 days after operation (endpoint). Left ventricular uncoupling protein-2 expression, creatine phosphate, and adenosine triphosphate were measured at endpoint. In perindopril-treated rats, systolic and diastolic blood pressure decreased after treatment (92+/-4/65+/-2 mm Hg). At endpoint, left ventricular end-diastolic dimension in untreated (10.7+/-0.2 mm) and treated rats (9.2+/-0.2 mm) was increased, and fractional shortening was reduced in untreated rats (28+/-1%) but did not change in treated rats (36+/-2%). Uncoupling protein-2 mRNA expression increased in untreated rats (3.7-fold) and was suppressed by perindopril (1.5-fold). The creatine phosphate was reduced in untreated rats (10.6+/-0.7 micro mol/g) but not in treated rats (15.9+/-2.0 micro mol/g). In the chronic stage of aortic regurgitation, perindopril improved cardiac performance and myocardial energy efficiency, in which the suppression of uncoupling protein-2 may play an important role.     

Diagnosis of deep vein thrombosis using multi-detector helical CT

PURPOSE: To evaluate the usefulness of multi-detector helical CT (MDHCT) with contrast medium in the diagnosis of deep vein thrombosis (DVT). Materials and Methods: The bilateral veins of the dorsal pedis in 45 patients (12 men, 33 women; average age, 64 years) under clinical suspicion of DVT were first punctured using 22-G needles. Then CT scanning from the level of the foot to the inferior vena cava was started 20 sec after the initial injection of 200 mL of dilute contrast medium (50 mL nonionic iodinated contrast medium of 300 mgI/mL and 150 mL saline) at a rate of 5 mL/sec. RESULTS: Two patients were excluded because of unsuccessful venous puncture. The average scanning time in 43 patients was 38.5 +/- 7.9 seconds. Images of veins from the foot to the inferior vena cava were clearly demonstrated in each case. MDHCT showed DVT in 32 cases and patent deep vein in 11 cases. Simultaneous venography of the lower extremity in 18 patients clearly visualized DVT at the same level detected by contrast MDHCT. CONCLUSION: MDHCT for the diangosis of DVT has the advantages of wider scanning range, shorter scanning time, and finer Z-axis resolution than the other diagnostic modalities.     

Laparoscopic ethanol injection therapy for hepatocellular carcinoma.

Ethanol injection into HCC tumors is an effective therapy and percutaneous ethanol injection therapy (PEIT) is performed on many HCC patients. However, there are cases in which PEIT becomes difficult because the HCC could not be detected by ultrasonography or the tumor is located in an area where it is impossible to perform PEIT. Nine patients with HCC underwent laparoscopic ethanol injection therapy (LEIT) in our institution. Their tumors were located on the liver surface and could be visualized by laparoscopic examination. Ethanol injection was performed under laparoscopic direct visualization. The total injected ethanol volume required ranged from 4 to 15 ml and in most cases both tumor size and alpha-fetoprotein (AFP) levels decreased after LEIT. Three cases showed a transient complication of abdominal pain or/and portal vein damage. Other severe complications were not observed. All cases required additional therapies, including transcatheter arterial chemoembolization (TAE) or PEIT to complete the tumor necrosis. In conclusion, LEIT is a safe and effective therapy for HCC located on the liver surface, but should be combined with other therapies to facilitate its effect against HCC.     

Increased MCL-1 expression is associated with poor prognosis in ovarian carcinomas.

To investigate the potential role of the BCL-2 gene family (BAX, BCL-2, MCL-1, and BCL-XL) in ovarian cancer development and progression, mRNA expression levels of these genes were measured using semi-quantitative PCR in epithelial ovarian tumor tissues and normal ovaries. The immunohistochemical expression of MCL-1 in ovarian tumors was also examined. The expression levels of BAX and MCL-1 mRNA were significantly higher in ovarian cancers and in adenomas than in normal ovaries (P < 0.05). In contrast, the BCL-2 mRNA expression level in ovarian cancers was significantly lower than in ovarian adenomas and in normal ovaries (P < 0.05). Expression of BCL-XL mRNA was no different between normal ovaries and ovarian tumors. Log-rank testing showed that low BAX mRNA expression and high MCL-1 mRNA expression significantly correlate with poor survival for patients with stage III ovarian carcinomas (BAX, P = 0.05; MCL-1, P = 0.02). Immunohistochemical analysis showed that diffuse-positive expression of MCL-1 protein in mucinous carcinomas was significantly higher than in mucinous low malignant potential (LMP) tumors (P = 0.03). In ovarian cancer cases, diffuse-positive expression of MCL-1 protein significantly correlates with advanced clinical stage, high histologic grade, and poor survival (stage, P < 0.01; grade, P = 0.01; survival, P = 0.01). These results suggest that increased MCL-1 expression may play an important role in replacing the functions of increased BAX and decreased BCL-2 in ovarian carcinoma cells, thereby promoting cell survival, and resulting in a poor prognosis for patients with ovarian cancer.     

The Expression of Invasive Behavior of Differentiated Squamous Carcinoma Cell Line Evaluated by an in vitro Invasion Model

In order to elucidate the factors contributory to the expression of invasiveness of oral squamous cell carcinoma, we conducted biochemical and morphological comparisons of well differentiated squamous carcinoma cell line OSC-19 (oral squamous cell carcinoma) and undifferentiated carcinoma cell line KB, both cultured on 3T3 cell-embedded collagen gel ( in vitro invasion model). OSC-19 cells invaded 3T3 cell-embedded collagen gel, while KB cells and OSC-19 cells on 3T3 cell-free gel matrix were less invasive. Cultured OSC-19 cells were characterized by lower proliferating activity, lower secretion of laminin and higher secretion of fibronectin than those of KB cells. Although the basement membrane with deposition of laminin and type IV collagen was formed, it was discontinuous at the invasion front. Gelatin zymography and western blotting showed matrix metalloproteinases (MMP), i.e., 72 kDa gelatinase (MMP-2) and 92 kDa gelatinase (MMP-9). Gelatinolytic activity was assayed, and was higher in OSC-19 cells than in KB cells or OSC-19 cells of the 3T3 cell-free model. By immuno-histochemical analysis, MMP-2-positive cells were found scattered in both cell lines without any preferential localization, and the positivity for MMP-9 was localized in the invasion front of OSC-19 cells. These results strongly suggest that the invasiveness of squamous cell carcinoma is well correlated with cell-matrix adhesion by fibronectin and with focal elaboration of metalloproteinases, especially MMP-9, which play a major role in degrading the extracellular matrix components.     

A case of stage IV gastric cancer previously treated with TS-1 completely responding to second-line chemotherapy with weekly paclitaxel therapy

We report herein a case with stage IV gastric cancer previously treated with TS-1 completely responding to second-line chemotherapy with weekly paclitaxel therapy. A 65-year-old female was diagnosed as having type 3 gastric cancer with para-aortic lymph node metastases. She underwent total gastrectomy with extended lymph node dissection on March 2003. Histopathological examination revealed that the tumor was poorly-differentiated adenocarcinoma with para-aortic lymph nodes metastases and completely resected.After the operation,she was treated by adjuvant chemotherapy with TS-1. In March of 2004, she suffered from hematuria, and a CT scan revealed para-aortic lymph nodes metastases and left kidney metastasis. Then, she was treated by a weekly infusion of paclitaxel as second-line chemotherapy. After 3 courses, the tumor disappeared and efficacy was judged as CR. Moreover, CR was maintained after 7 courses. At this writing in January of 2005, she is well and has been treated with paclitaxel without any severe adverse events. Therefore, weekly paclitaxel therapy was considered to be one of the promising second-line chemotherapies for advanced or recurrent gastric cancer previously treated by TS-1.     

Inhibitory effects of environmental chemicals on protein disulfide isomerase in vitro

BACKGROUND: The influence of endocrine disrupting chemicals (EDCs) upon physiological functions and their mechanisms is of concern. We have previously demonstrated that protein disulfide isomerase (PDI) was a target molecule of bisphenol A (BPA), which is considered to be EDC. PDI plays a key role in protein folding as an isomerase and also possesses a 3,3',5-triiodo-L-thyronine (T3)-binding activity. Since PDI activities were inhibited by BPA in our previous study, BPA might have adverse effects on physiological functions via the inhibition of PDI activities. We conducted this study to identify the compounds which disturb PDI activities as well as BPA, and to discuss their structural characteristics. METHODS: We examined the effects of 22 suspected EDC on both the T3-binding activity and isomerase activity of rat recombinant PDI. RESULTS: Among the 22 compounds, only phenolic compounds, namely BPA, p-octylphenol, p-nonylphenol, 2,4-dichlorophenol, pentachlorophenol, tetrabromobisphenol A, and tetrachlorobisphenol A, inhibited T3 binding to PDI. Furthermore non-halogenated compounds among these phenolic compounds, such as BPA, p-octylphenol, and p-nonylphenol, showed inhibitory effects on the isomerase activity of PDI. CONCLUSIONS: Our results suggest that phenolic groups might have important inhibitory effects on the T3-binding activity of PDI, and that compounds with phenolic groups might have the same effects on PDI. Furthermore, non-halogenated phenolic compounds had inhibitory effects on the isomerase activities of PDI in addition to T3-binding activity, indicating that these compounds might also have adverse effects on protein folding, which PDI participates in by catalyzing rearrangements of disulfide bonds as an isomerase.