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Background and Purpose: Recently, Lee et al reported a new grading system for the lumbar spinal foraminal stenosis. They considered the type of stenosis, the amount of fat obliteration, and the presence of nerve root compression. Our aim was to evaluate whether a new MR imaging grading system correlated with symptoms and neurologic signs and could replace the previous grading system., Materials and Methods: We examined 91 patients (M/F = 49:42; mean age, 50 years) who visited our institution and underwent MR imaging of the L-spine and were evaluated by 2 musculoskeletal radiologists. The presence and grade of lumbar foraminal stenosis at the maximal narrowing point was assessed according to the new grading system suggested by Lee et al (Lee system) and the Wildermuth grading system (Wildermuth system). Results were correlated with clinical manifestations and neurologic physical examination. Statistical analysis was performed by using κ statistics, categoric regression analysis, and nonparametric correlation analysis (Spearman correlation)., Results: Interobserver agreement in the grading of foraminal stenosis between the 2 readers was substantially correlated (κ of Lee system = 0.767, κ of Wildermuth system = 0.734). The Rs for reader 1 and reader 2 between the Lee system and the Wildermuth system were 0.880 and 0.885, between Lee system and PNM were 0.715 and 0.604, and between the Wildermuth system and PNM were 0.800 and 0.680. For patients younger than 50 years of age, the R between the Lee and Wildermuth systems was higher than that for patients 50 years or older, but the Rs between the grading system and PNM were lower in the younger group than in the older group. The Rs of the Wildermuth system with PNM were higher in the older group than in the younger group; the differences between the Rs of the Lee system with PNM and the Wildermuth system with PNM were higher in the older group (0.016 [young] versus 0.130 [old] and 0.008 versus 0.107)., Conclusions: Interobserver agreement of the Lee system was slightly higher than the Wildermuth system and substantially correlated. Both systems are good for evaluation of lumbar spinal foraminal stenosis, but the Lee system showed slightly better interobserver agreement and good clinical correlation in the younger group of patients.

Aim: To evaluate the accuracy of magnetic resonance imaging (MRI) findings in chronic lateral ankle ligament injury in comparison with that of surgical findings., Materials and Methods: Forty-eight cases (25 men, 23 women, mean age 36 years) of clinically suspected chronic ankle ligament injury underwent MRI studies and surgery. Sagittal, coronal, and axial, T1-weighted, spin-echo, proton density and T2-weighted, fast spin-echo images with fat saturation were obtained in all patients. MRI examinations were read in consensus by two fellowship-trained academic musculoskeletal radiologists who evaluated the lateral ankle ligaments, including the anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) without clinical information. The results of the MRI studies were then compared with the surgical findings., Results: The MRI findings of ATFL injury showed a sensitivity of detection of complete tears of 75% and specificity of 86%. The sensitivity of detection of partial tears was 75% and the specificity was 78%. The sensitivity of detection of sprains was 44% and the specificity was 88%. Regarding the MRI findings of CFL injury, the sensitivity of detection of complete tears was 50% and the specificity was 98%. The sensitivity of detection of partial tear was 83% and the specificity was 93%. The sensitivity of detection of sprains was 100% and the specificity was 90%. Regarding the ATFL, the accuracies of detection were 88, 58, 77, and 85% for no injury, sprain, partial tear, and complete tear, respectively, and for the CFL the accuracies of detection were 90, 90, 92, and 96% for no injury, sprain, partial tear, and complete tear, respectively., Conclusions: The diagnosis of a complete tear of the ATFL on MRI is more sensitive than the diagnosis of a complete tear of the CFL. MRI findings of CFL injury are diagnostically specific but are not sensitive. However, only normal findings and complete tears were statistically significant between ATFL and CFL (p < 0.001)., (Copyright © 2011 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) commonly occurs in individuals receiving bisphosphonates (BPs) with clinical manifestations of the exposed necrotic bone. Although defective wound healing of soft tissue is frequently, if not always, observed in BRONJ, the effects of BPs on oral soft tissue or cells remain unknown. To investigate the effects of BPs on cells of oral mucosal tissue, we studied the effect of pamidronate (PAM), one of the BPs most commonly administered to cancer patients, on the phenotypes of normal human oral keratinocytes (NHOK) and fibroblasts (NHOF). When exposed to PAM at 10 µM, NHOK, not NHOF, underwent senescence: NHOK overexpressed senescence-associated β-galactosidase (SA-β-Gal), p16INK4A, IL-6, and IL-8. When exposed to a higher level (50 µM) of PAM, NHOK maintained senescent phenotypes, but NHOF underwent apoptosis. PAM-induced senescence in NHOK is mediated, in part, via geranylgeranylation of the mevalonate pathway. Our in vitro 3D oral mucosal tissue construction studies further demonstrated that PAM induced senescence and impaired re-epithelialization of oral mucosa. Analysis of these data indicates that premature senescence of oral mucosal cells and subsequent defective soft-tissue wound healing might be partly responsible for the development of BRONJ in individuals receiving PAM or other BPs.

AST is commonly associated with pyriform sinus-thyroid fistula in children. Radiologic findings of AST are documented in a few reports. We report a new sign we term the "emerging echogenic tract sign," which reflects a patent air-containing pyriform sinus-thyroid fistula on follow-up US. Recognition of this sign is an important finding suggesting an associated pyriform sinus-thyroid fistula in a patient with AST and also suggesting the adequate timing of barium esophagography to confirm the fistula.

Background: Uterine sarcomas are rare among all uterine malignancies, and frequently misdiagnosed as benign uterine diseases such as leiomyoma and adenomyosis because of lack of feasible tools for the preoperative diagnosis. Although some studies have suggested the role of serum CA-125 levels for the preoperative diagnosis, the efficacy is controversial. Since malignancy is known to be associated with systemic inflammation which leads to hematological alteration, we compared the efficacy for the preoperative diagnosis of uterine sarcomas between the neutrophil to lymphocyte ratio (NLR) and serum CA-125 levels using a case-match comparison., Methods: From November 2004 to December 2008, 55 patients with carcinosarcoma (n=21), leiomyosarcoma (n=20) and endometrial stromal sarcoma (n=14) were matched to 330 patients with leiomyoma (n=165) and adenomyosis (n=165) in terms of age at diagnosis, body mass index and uterine volume., Results: The receiver operating characteristic curve showed the best cut-off values of the NLR (>or=2.12) and serum CA-125 levels (>or=27.5U/ml) for the preoperative diagnosis of uterine sarcomas, demonstrating that the NLR was more powerful for the preoperative diagnosis of uterine sarcomas than serum CA-125 levels (sensitivity, 74.5% vs. 52.3%; specificity, 70.3% vs. 50.5%; positive predictive value, 29.5% vs. 15.1%; negative predictive value, 94.3% vs. 86.5%; accuracy, 60.6% vs. 49.6%; p<0.05). Furthermore, the NLR reflected recurrence and progression more accurately than serum CA-125 levels in patients with uterine sarcomas., Conclusions: These findings suggest that the NLR may be more useful than serum CA-125 levels as a cost-effective tool for the preoperative diagnosis in patients with uterine sarcomas.

We report three cases of eosinophilic cystitis. Contrast-enhanced computed tomography (CT) revealed characteristic bladder wall thickening exceeding 10 mm, with preservation of the mucosal lining and intense, progressive contrast enhancement on sequential arterial and delayed scans. Eosinophilic cystitis might have been associated with eosinophilic infiltration in other organs, such as the gastrointestinal tracts and liver.

Aims: The purpose of this study was to examine the clinical impact of under-diagnosis by frozen section examination in borderline ovarian tumors (BOTs)., Methods: We reviewed 209 consecutive patients with BOTs who were diagnosed and treated at our institute between March 1988 and July 2007. Tumors from 182 of 209 patients were evaluated by frozen section examination. After excluding a case with a deferred diagnosis, the results of frozen section examinations were compared with the final paraffin section examination. In 61 patients, the frozen section examination under-diagnosed a BOT as a benign tumor. In 120 patients, the frozen section examination correctly diagnosed or over-diagnosed a BOT. The clinical impact of under-diagnosis was evaluated by comparing the extent of surgery and treatment outcome between the patients who were under-diagnosed (study group) and the patients who were not under-diagnosed (control group)., Results: The study group had more mucinous (P=0.03) and/or stage 1A (P=0.02) tumors than the control group. Fewer patients in the study group received adjuvant chemotherapy than the patients in the control group (P=0.02). Fewer patients in the study group underwent radical surgery than the patients in the control group (P=0.02). However, the rates of treatment failure were similar between the two groups (no treatment failure in the study group and seven treatment failures in the control group; P=0.10)., Conclusions: The under-diagnosis by frozen section examination did not compromise the outcome in patients with BOTs, although under-diagnosis was associated with more conservative surgery.

Background: Epithelial ovarian cancer is one of the most lethal malignancies, and has a high recurrence rate. Thus, prognostic markers for recurrence are crucial for the care of ovarian cancer. As ovarian cancers frequently exhibit chromosome instability, we aimed at assessing the prognostic significance of two key mitotic kinases, BubR1 and Aurora A., Methods: We analysed paraffin-embedded tissue sections from 160 ovarian cancer patients whose clinical outcomes had been tracked after first-line treatment., Results: The median recurrence-free survival in patients with a positive and negative expression of BubR1 was 27 and 83 months, respectively (P<0.001). A positive BubR1 expression was also associated with advanced stage, serous histology and high grade. In contrast, Aurora A immunostaining did not correlate with any of the clinical parameters analysed., Conclusion: BubR1, but not Aurora A, is a prognostic marker for recurrence-free survival rates in epithelial ovarian cancers.

Background: We sought to identify the role of serum CA-125 levels in early-stage epithelial ovarian cancer (EOC) on preoperative CT and MRI., Methods: Clinical data of 101 patients with early-stage EOC on preoperative CT and MRI were collected between January 2000 and December 2007. Clinical stage I (n=59) was defined as tumor limited to the ovaries with or without ascites, whereas clinical stage II (n=42) was defined as tumor within the pelvis with or without ascites. The primary endpoint was to investigate the efficacy of serum CA-125 levels for the prediction of advanced-stage disease, and secondary endpoints were to evaluate the accuracy of preoperative CT and MRI, and to examine the role of serum CA-125 levels as a prognostic factor for survival., Results: The results of preoperative CT and MRI were concordant with no peritoneal implants outside the pelvis in 50/101 (50%) and no lymph node metastasis in 71/101 (70%) patients. The receiver operating characteristic curves showed that best cut-off values of serum CA-125 levels were 320 U/ml (71% sensitivity, 84% specificity) and 510 U/ml (67% sensitivity, 80% specificity) for the prediction of peritoneal implants outside the pelvis and lymph node metastasis. The serum CA-125 level (> or =320 U/ml) was a significant factor for the prediction of advanced-stage disease (adjusted OR, 7.43; 95% CI, 2.39-23.04). However, it was not an independent prognostic factor for survival., Conclusions: Serum CA-125 levels may be very useful for the prediction of advanced-stage disease in early-stage EOC on preoperative CT and MRI.

Aims: In cervical cancer patients with intermediate-risk factors, the optimal adjuvant therapy is still controversial. We retrospectively compared the treatment outcome of chemoradiation with that of radiation., Methods: From 1997 to 2005, 79 consecutive cervical cancer patients received postoperative adjuvant therapy indicated by intermediate-risk factors. Fifty-five women received chemoradiation and 24 women received radiation. Risk factors, recurrence-free survival (RFS), adverse events, and recurrence pattern were investigated and were compared between the chemoradiation and radiation groups. RFS was calculated by the Kaplan-Meier method and was compared by the log-rank test., Results: Risk factors were well-balanced between the two groups. Four patients recurred in the chemoradiation group and eight patients recurred in the radiation group. RFS rate of the chemoradiation group was significantly higher than that of the radiation group (P=0.01). Hematologic toxicity was more common in the chemoradiation group than in the radiation group (P<0.01). However, non-hematologic toxicity was similar between the two groups and most of the patients (97%) completed postoperative adjuvant therapy. Recurrence pattern was similar between the two groups., Conclusion: In cervical cancer patients with intermediate-risk factors, chemoradiation was well-tolerated and more effective than radiation as a postoperative adjuvant therapy.

Higher expression of human telomerase reverse transcriptase (hTERT) and subsequent activation of telomerase occur during cellular immortalization and are maintained in cancer cells. To understand the mode of hTERT expression in cancer cells, we identified cancer-specific trans-regulatory proteins that interact with the hTERT promoter, using the promoter magnetic precipitation assay coupled with mass spectrometry. The identified proteins include MutS homolog 2 (MSH2), heterogeneous nuclear ribonucleoprotein (hnRNP) D, hnRNP K and grainyhead-like 2 (GRHL2). We noticed a higher expression of these proteins in human oral squamous cell carcinoma (OSCC) cells than in normal cells, which do not exhibit telomerase activity. Knockdown of MSH2, hnRNP D and GRHL2 resulted in a notable reduction of the hTERT promoter activity in tested cancer cells. Silencing of the above genes resulted in a significant reduction of the telomerase activity in OSCC cells. Interestingly, among the four identified genes, silencing of GRHL2 was essential in reducing telomerase activity and viability of tested cancer cells. These results suggest a possible role of GRHL2 in telomerase activation during cellular immortalization.

We report the case of an anomalous left anterior descending (LAD) artery with myocardial bridging, which originated from the proximal right coronary artery in a patient with a true LAD artery.

Granulosa cell tumor (GCT) of the ovary is a very rare neoplasm, which is characterized by an indolent clinical course. Thus, the clinical characteristics, optimal treatment, and follow-up protocols are not well established. The goal of this study is to evaluate clinical findings, prognostic factors, and recurrent features of GCT in Korean patients. Between 1987 and 2005, 42 cases of GCT were diagnosed in our institution. There were 35 cases showing adult-type GCT, which were available for evaluation. All charts were reviewed, and the clinical data along with treatment results were retrospectively studied. Statistical analyses were performed for risk factors of recurrence and disease-free survival. GCT accounted for 3% of all ovarian malignancies in our institution during the study period. The median age was 45 years (range, 24-68 years). Abdominal and hormone-related symptoms were the main causes of first presentation. There were eight cases of recurrence including two cases of disease-related deaths during the median follow-up period of 177 months (range, 8-212 months). Factors affecting the recurrence involved residual tumor and stage, but residual tumor was the only significant factor of recurrence in multivariate analysis. The median time to relapse was 75 months (range, 55-137 months), and the liver was the most common extra-pelvic metastatic site followed by the intestine. Continuous long-term follow-up with pelvic and whole-abdominal surveillance is absolutely required. Active management including complete tumorectomy is the most important treatment modality in both primary surgeries and recurrent cases.

Background: Many studies have shown that a polymorphism (G870A) in cyclin D1 (CCND1) is associated with carcinogenesis in a variety of cancers. Our aim was to determine if an association exists between the CCND1 G870A polymorphism and uterine leiomyoma in Korean women., Methods: Blood samples of 331 cases and 204 controls aged 47.4 +/- 7.6 and 46.8 +/- 10.4 years (mean +/- SD), respectively, were collected. CCND1 genotyping was determined by PCR and restriction fragment length polymorphism., Results: Allelic frequencies of cases (A, 0.53; G, 0.47) were not significantly different from those of controls (A, 0.49; G, 0.51) (P = 0.22). After adjustment for menarche age and BMI, multivariate logistic regression analysis showed that the AA genotype was not associated with increased risk for uterine leiomyoma [odds ratio (OR) = 1.38, 95% confidence interval (CI); 0.85-2.26, P = 0.19]. However, in stratification analysis of cases and controls with BMI >25 kg/m(2), allelic frequencies of cases (A, 0.56; G, 0.44) were significantly different from controls (A, 0.36; G, 0.64) (P = 0.005), and the AA genotype was associated with increased risk for uterine leiomyoma (OR = 3.61, 95% CI; 1.02-12.73, P = 0.046). Furthermore, the OR for AA compared with combined GG and AG genotypes was 3.16 (95% CI 1.01-9.92, P = 0.048)., Conclusions: The A allele and AA genotype of CCND1 G870A polymorphism have a significant association with an increased risk of the uterine leiomyoma in obese Korean women.

Dichloromethane, ethanol, and boiling water extracts of the brown seaweeds Sargassum fulvellum and Sargassum thunbergii were examined for antipyretic, analgesic, and anti-inflammatory activities in mice. The activities were evaluated against yeast-induced pyrexia, tail-flick test, and phorbol myristate acetate-induced inflammation (edema, erythema, and blood flow). The dichloromethane extract (0.4 mg/ear) of Sargassum fulvellum inhibited an inflammatory symptom of mouse ear edema by 79.1%. The ethanol extract (0.4 mg/ear) of Sargassum thunbergii also inhibited edema by 72.1%. No acute toxicity was observed after p.o. administration of each extract (5 g/kg bw). These findings are consistent with various claims that these seaweeds can be used as remedies for inflammation-related symptoms.

Amyloidosis involving the mesentery is very rare, and its radiological appearance has been poorly documented. To our knowledge, this is the first case of amyloidosis involving the mesentery being presented as a mesenteric haematoma.

The aim of this study was to identify ultrasonographic findings that show the normal faecal-impacted appendix, in order to avoid unnecessary surgery via a misdiagnosis of acute appendicitis. Of 160 patients who underwent ultrasonography between January 2004 and July 2005 for right lower quadrant pain, 22 cases (including 7 cases confirmed pathologically and 15 confirmed clinically and on follow-up ultrasonography) were diagnosed as a normal faecal-impacted appendix. The criteria that we used to distinguish a faecal-impacted appendix from acute appendicitis include preservation of the normal wall layering of the appendix, maximum mural thickness, presence of peri-appendiceal fat infiltration and increased blood flow in the appendiceal wall. The maximum measured outer diameter of a normal faecal-impacted appendix was 0.54-1.03 cm, with a mean diameter of 0.68 cm. The maximum mural thickness ranged from 0.08 cm to 0.26 cm, with a mean thickness of 0.15 cm. The normal wall layers of the appendix were preserved and no evidence was seen of peri-appendiceal fat infiltration in any case. No demonstrably increased blood flow in the appendiceal wall was observed. In conclusion, faecal impaction increases the outer transverse diameter of the normal appendix, frequently leading to a misdiagnosis of acute appendicitis. Recognition of preservation of the normal layering of the appendiceal wall, smaller maximal outer diameter, thinner maximal mural thickness, the absence of peri-appendiceal mesenteric infiltration and no demonstrably increased blood flow in the appendiceal wall should help to prevent unnecessary surgery.

The purpose of this study was to evaluate the typical ultrasonographic findings of transient small bowel intussusception (SBI) and to differentiate it from ileocolic intussusception (ICI) in paediatrics. 22 transient SBI (male:female = 13:9, age: 7-132 months (mean 38 months)) and 27 ICI (male:female = 19:8, age: 1-60 months (mean 13 months)) patients diagnosed on ultrasonography were retrospectively evaluated. The findings of location, diameter, thickness of outer rim, and inclusion of mesenteric lymph nodes within intussuscipiens were compared. In the transient SBI, the head of intussusception was located in the right lower quadrant (RLQ) in 11 (50%), the right upper quadrant (RUQ) in 2 (9.1%) and the periumbilical area in 9 (40.9%) cases. The anteroposterior (AP) diameter ranged from 0.84-2.4 cm (mean 1.38 cm), and thickness of outer rim ranged from 0.10-0.34 cm (mean 0.26 cm). No mesenteric lymph nodes were contained within the intussuscipiens. In the ICI, the head was located in the RUQ in 17 (63%), the epigastrium in 7 (25.9%) and the left upper quadrant in 3 (11.1%) cases. The AP diameter ranged from 1.89-3.32 cm (mean 2.53 cm), and the thickness of the outer rim ranged from 0.30-0.86 cm (mean 0.53 cm). Mesenteric lymph nodes were contained within the intussuscipiens in 26 (96.3%) cases. In conclusion, when compared with ICI, the transient SBI occurs predominantly in the RLQ or periumbilical region, has a smaller AP diameter, a thinner outer rim, and dose not contain mesenteric lymph nodes.

Background and Purpose: An increase in the common carotid artery intima-media thickness (CCA-IMT) is generally considered an early marker of atherosclerosis. This cross-sectional study assessed the CCA-IMT and plaque score as vascular risk factors in patients with ischemic stroke and type 2 diabetes., Materials and Methods: Brain MR imaging and carotid ultrasonography were performed in 133 subjects with type 2 diabetes. IMT was measured at both CCAs. Differences in the variables between case and control subjects were compared statistically. To determine the independent factors related to CCA-IMT and plaque score, we performed stepwise multiple regression analysis., Results: Sex, current smoking habit, history of hypertension, and high-density lipoprotein (HDL) levels differed significantly between the case and control groups. CCA-IMT and plaque score in patients with diabetes and acute ischemic stroke were significantly greater than in patients with diabetes who were stroke-free. The crude odds ratios suggested that CCA-IMT and plaque score are risk factors of acute ischemic stroke in patients with type 2 diabetes. However, when we adjusted for cerebrovascular risk factors, CCA-IMT and plaque score did not remain significantly associated with acute ischemic stroke., Conclusion: Increased CCA-IMT and plaque score are associated with acute ischemic stroke in patients with type 2 diabetes. The higher CCA-IMT and plaque score found in ischemic stroke in patients with type 2 diabetes seem to be induced by cerebrovascular risk factors. Therefore, to prevent ischemic stroke in patients with type 2 diabetes, strict control of hyperglycemia, hypertension, smoking, and low HDL, together with monitoring of CCA-IMT and carotid plaque, may be important.

Cervical cancer, the second most common malignancy in women worldwide, is almost invariably associated with infection by human papillomavirus (HPV). However, although many women are infected with high-risk types of HPV, only a subset of infected women will ever develop cervical cancer. Therefore, host genetic factor may play a role in cervical carcinogenesis. Alterations in epidermal growth factor receptor (EGFR) are common events in cervical cancer. Therefore, we hypothesized that a functional polymorphism in the 5' untranslated region of the epidermal growth factor (EGF) gene, a natural ligand of the EGFR, may play a role in the cervical carcinogenesis and tumor invasiveness. We assessed the possible association between EGF +61 A/G polymorphism and cervical cancer risk in a hospital-based case-control study among 337 Korean women (168 cases, 169 age-matched controls). The frequencies of EGF +61 allele and genotype were not different between cases and controls. We observed increasing trend of lymph node metastasis from A/A homozygous genotype toward G/G homozygous genotype. We did not find any evidence that EGF +61 A/G polymorphism was associated with individual susceptibility of cervical cancer. However, although it was not statistically significant, the increasing trend of lymph node metastasis according to EGF genotype suggests the possibility that individual variance of EGF expression may be associated with cervical cancer invasiveness. We also confirmed that there exists striking ethnic heterogeneity of EGF genotype between Caucasian and East Asian population.

Introduction: The effect of epigallocatechin gallate (EGCG) in an in vivo renal model of ischemia with reperfusion (I/R) was compared between normotensive (WKR) and hypertensive (SHR) rats., Methods: WKR (groups I, II, III) and SHR groups (groups IV, V, VI) were divided into three types. Groups I and IV were sham-operated animals; groups II and V were subjected to 45 minutes of renal I/R; and groups III and VI received 10 mg/kg EGCG intravenously at the time of reperfusion. Three days after renal I/R, we compared renal function markers, malondialdehyde (MDA), and histologic changes., Results: Following renal I/R, levels of blood urea nitrogen (BUN) and serum creatinine (sCr) were increased and serum creatinine clearance (CrCl) decreased in group V compared to group II (P < .001). Those receiving EGCG treatment (groups III and VI) had decreased BUN and sCr compared to non-EGCG I/R groups (P < .001), but not surprisingly, higher than sham groups. CrCl was lowest in the SHR groups. The MDA was significantly decreased after EGCG treatment (P = .028 in group III, P = .002 in group VI). Following renal I/R, tissue necrosis was more severe among SHR (P < .001). However, the ratio of regeneration to damage significantly increased in SHR after EGCG treatment., Conclusions: The reperfusion injury was greater among SHR compared with WKR in terms of renal function, lipid peroxidation, and tissue damage. EGCG treatment significantly ameliorated renal impairment and promoted tissue regeneration following renal I/R.

Hepatocellular carcinoma (HCC) is the fifth most common cancer in the world, and has a wide geographical variation. Eighty per cent of HCC is attributed to hepatitis B virus (HBV). The predominant carcinogenic mechanism of HBV associated HCC is through the process of liver cirrhosis, but direct oncogenic effects of HBV may also contribute. Prevention of HBV infections as well as effective treatment of chronic hepatitis B is still needed for the global control of HBV associated HCC. Continued investigation of the mechanisms of hepatocarcinogenesis will refine our current understanding of the molecular and cellular basis for neoplastic transformation in the liver.

Objective: To assess the performance of inexperienced gynecology residents in the evaluation of adnexal masses using sonographic scoring systems., Methods: From April 2003 to October 2004, transvaginal sonography was performed preoperatively by junior gynecology residents on 1-month shifts on 123 patients suspected of having adnexal masses. A total of 137 adnexal masses were found and evaluated using two different morphological scoring systems (those of DePriest and Lerner). The diagnostic performance of the sonographic scoring systems was assessed using the McNemar test and receiver-operating characteristics (ROC) curve analysis was used for lesion characterization. The diagnostic accuracy when the results of both scoring systems satisfied malignancy cut-off values was also investigated., Results: Histopathological analysis revealed that, of the 137 lesions, 109 were benign, 23 were malignant and five were borderline. Best clinical cut-off levels were > or = 5 on the DePriest and > or = 3 on the Lerner scores. Both systems achieved good performance for characterizing malignancy. No significant difference was found in terms of the accuracy of the two systems as determined by mean areas under the ROC curves (0.816 and 0.783, P = 0.562). The combined approach using both scoring systems resulted in higher specificity (77.1%, P < 0.05) and positive predictive value without a significant decrease in sensitivity (82.1%) compared with either system alone. Of the 43 histologically confirmed false-positive cases, mature cystic teratoma was most common, with 13/22 (59%) cases being misinterpreted as malignancies., Conclusion: Junior residents, inexperienced at sonography, performed fairly in terms of evaluating adnexal masses with the help of morphological scoring systems.

The efficacy of lamivudine re-treatment in chronic hepatitis B (CHB) patients who relapse after HBeAg seroconversion with lamivudine has not been investigated. The aim of this study was to evaluate the efficacy of lamivudine re-treatment in relapsed patients. Among 192 patients who had achieved HBeAg seroconversion with lamivudine at a dose of 100 mg/day, 121 patients discontinued lamivudine. Relapse occurred in 49 patients (40.5%). Thirty-three relapsed patients received lamivudine re-treatment for at least 6 months. The mean duration of lamivudine re-treatment was 16 months and the follow-up period was 8.9 months. HBeAg seroconversion was achieved in 23 patients (69.7%). The cumulative HBeAg seroconversion rates at 5, 9, and 12 months were 60, 64, and 67%, respectively. The mean time to HBeAg seroconversion in lamivudine re-treatment was shorter than that in the initial therapy (4.7 months vs. 9.7 months). Viral breakthrough occurred in six (18.2%) patients. All patients with viral breakthrough were accompanied by elevation of serum alanine aminotransferase (ALT) levels. Among 15 patients who discontinued lamivudine re-treatment after HBeAg seroconversion, relapse occurred in six patients (40%). All relapses occurred within 9 months after the discontinuation of lamivudine re-treatment. In conclusion, lamivudine re-treatment in relapsed patients after initial lamivudine therapy had a higher response rate and shorter duration to HBeAg seroconversion than during the initial therapy. However, HBeAg seroconversion induced by lamivudine re-treatment was not durable.

The aim of this study was to determine whether the changing patterns of quantitative hepatitis B e antigen (HBeAg) levels by serial monitoring could predict HBeAg seroconversion and viral breakthrough during lamivudine therapy. We retrospectively analysed 340 HBeAg positive naive chronic hepatitis B patients treated with lamivudine. The mean duration of lamivudine therapy was 18.7 (range 6-56) months. The changing patterns and reduction rates of pretreatment HBeAg levels by serial monitoring were categorized into three groups: Decrescendo group (n = 195), Decrescendo-crescendo group (n = 65) and no changing or fluctuating group (n = 80). Of 109 patients who had achieved HBeAg seroconversion, 105 (96.3%) were included in the decrescendo group. The decrescendo group, pretreatment quantitative HBeAg levels, alanine aminotransferase levels, and the duration of lamivudine therapy were independent predictive factors for HBeAg seroconversion. Of 82 patients who had viral breakthrough, 53 (64.6%) were in the decrescendo-crescendo group and 21 (25.6%) were in the no changing or fluctuating group. The only predictive factor for viral breakthrough was the changing patterns of quantitative HBeAg levels, especially, the decrescendo-crescendo group and the no changing or fluctuating group. The mean time of turning points in the decrescendo-crescendo group was 7.1 months earlier than the mean time of viral breakthrough (9.0 months vs 16.5 months). Therefore, the changing patterns of quantitative HBeAg levels by serial monitoring during lamivudine therapy may allow not only the prediction of treatment responses, but also an early recognition of a viral breakthrough.

The Regional Research Centers for Minority Oral Health (RRCMOH) helped to redefine the research and education missions of the participating institutions, and placed new emphasis on early diagnosis, prevention, and conservative interventions in minority-related oral diseases, with an eye toward innovative, cost-effective solutions to long-neglected and underfunded areas of dental and craniofacial research, education, and health promotion programs. This article reviews the legacy of the RRCMOH.

Many human cancers contain a hemizygous point missense mutation in p53, allowing expression of both wild-type and mutant p53. To understand the relationship between wild-type and mutant p53 in cells, we investigated the influence of a naturally occurring temperature-sensitive mutant p53 (valine to alanine substitution at codon 143: mp53-143ala) on the life span of normal human oral keratinocytes (NHOK) and the expression of wild-type p53. We also investigated the effect of the mutant p53 on the genetic stability of NHOK. The mp53-143ala extended the in vitro life span of NHOK by four-fold, but failed to overcome the M2 crisis stage for immortalization. The mp53-143ala notably suppressed wild-type p53 in NHOK at post-transcriptional levels. Moreover, the mp53-143ala notably increased both spontaneous and genotoxic agent-induced mutation frequency of a shuttle vector in NHOK. These data indicate that mutant p53 induces genetic instability by, in part, inhibiting the expression of wild-type p53 through a dominant negative role in cells expressing both mutant and wild-type p53.

A lentiviral vector capable of expressing the HIV-1 vpr gene (Vpr lentiviral vector) was constructed, and its in vivo anticancer effect was determined against cutaneous tumors derived from the AT-84 oral cancer cells in immunocompetent mice. A single intratumoral injection of the Vpr lentiviral vector not only significantly reduced the primary tumor volume but also completely regressed tumors in >40% of animals. More interestingly, the mice of which the primary tumors were completely regressed by the Vpr lentiviral vector were additionally protected from a secondary challenge of AT-84 cells. These data suggest that the Vpr lentiviral vector elicits its anticancer activity in part by the activation of the immune system. The above suggestion is additionally supported by the failure of the lentiviral vector to demonstrate anticancer activity in immunocompromised nude or SCID mice. The Vpr lentiviral vector offers a powerful new strategy for cancer gene therapy and may be useful for the control of solid tumors, such as human oral squamous cell carcinomas.

Purpose: Telomerase is a ribonucleoprotein complex composed of the catalytic protein subunit (human telomerase reverse transcriptase or hTERT) and the RNA template. This enzyme activity is a necessary and rate-limiting step of cellular immortalization and could provide a unique marker of aberrant cells, which may selectively be targeted. The current study was undertaken to quantitatively determine the degree of telomerase activation during multistage oral carcinogenesis using paraffin-embedded tissue samples., Experimental Design: hTERT expression level was quantitatively compared between normal and cancerous oral tissues by real-time reverse-transcription-PCR (RT-PCR). Also, the presence of hTERT transcript in individual cells was surveyed in the biopsy specimens with varying degrees of histopathology by in situ RT-PCR., Results: Low level of hTERT amplification was detected by real-time RT-PCR in most (11/13) normal human oral mucosa. hTERT expression was also detected in the majority (11/12) of squamous cell carcinoma tissues, and the level was significantly (P < 0.05) elevated, on the average, by a factor >6.9. By in situ RT-PCR, hTERT expression was not noted in normal epithelium (0/10) nor in mild dysplasia (0/7) but was detected in moderate dysplasia (4/5) and in those tissues with a higher grade of histopathology: severe dysplasia (3/3) and invasive carcinoma (4/4)., Conclusions: These results indicate that enhanced expression of telomerase activity occurs early during human oral carcinogenesis and support the critical role of telomerase in the development of human oral cancer.

The ability to penetrate tissue is an important virulence factor for pathogenic spirochetes. Previous studies have recognized the role of motility in allowing pathogenic spirochetes to invade tissues and migrate to sites favorable for bacterial proliferation. However, the nature of the movements, whether they are random or controlled by chemotaxis systems, has yet to be established. In this study, we addressed the role of motility and chemotaxis in tissue penetration by the periodontal disease-associated oral spirochete Treponema denticola using an oral epithelial cell line-based experimental approach. Wild-type T. denticola ATCC 35405 was found to penetrate the tissue layers effectively, whereas a nonmotile mutant was unable to overcome the tissue barrier. Interestingly, the chemotaxis mutants also showed impaired tissue penetration. A cheA mutant that is motile but lacks the central kinase of the chemotaxis pathway showed only about 2 to 3% of the wild-type penetration rate. The two known chemoreceptors of T. denticola, DmcA and DmcB, also appear to be involved in the invasion process. The dmc mutants were actively motile but exhibited reduced tissue penetration of about 30 and 10% of the wild-type behavior, respectively. These data suggest that not only motility but also chemotaxis is involved in the tissue penetration by T. denticola.

The hamster and human TERT promoters share common critical protein binding sites, such as the GC-box or E-box, which is known to be a binding site for Sp1/Sp3 transcriptional factors and c-Myc, respectively. Our previous data demonstrated that Sp1/Sp3 synergistically transactivate the hamster TERT (hamTERT) promoter. In this study, we determined the role of c-Myc in the regulation of hamTERT, and analyzed the relative significance of GC-boxes and the E-box for transcriptional activation of hamster TERT. Wild-type, mutated E-box or mutated GC-box hamTERT core promoter reporter was introduced into 293T cells in combination with murine or human Myc expression vectors. The promoter activity was determined using the luciferase assay, and the transfection efficiency was normalized with CAT activity. The electrophoretic mobility shift assay (EMSA) was done to prove the nuclear protein binding activity of the GC-box (region II) or E-box. Overexpression of murine or human Myc transactivated hamTERT core promoter activity. Inversion mutation in the E-box or substitution mutation in the GC-boxes abrogated endogenous or Myc induced hamTERT transactivation. Region II is the single most important Sp1/3 binding site in transcriptional activation, and multiple combined mutations in the GC-boxes abolished the hamTERT promoter activity. These results indicate that c-Myc and Sp1/3 are the major regulatory determinants of the hamTERT transcriptional activation. The mechanism of TERT gene activation during immortalization and carcinogenesis may be conserved among species.

The oral bacteria Actinomyces naeslundii and Actinomyces viscosus are known to contribute to the initiation and progression of human dental caries, especially root caries. We report that both A. naeslundii and A. viscosus react with a component in the Gardenia jasminoides extract to produce a distinct green product. This green color reaction was found to be dependent on the bacterial beta-glucosidase. The reaction is specific for cariogenic actinomyces, and it can detect as few as 10(4) cells of A. naeslundii and A. viscosus per ml.

Topical application of 7,12-dimethylbenz(alpha)-anthracene induces tumors in the hamster cheek pouch. Telomerase activity is increased in the cancer tissues if compared to normal adjacent tissues in both human and hamster oral cancer. In order to achieve a probe and to investigate the putative role of telomerase in oral carcinogenesis using the hamster cheek pouch model, we have cloned the cDNA encoding the hamster telomerase catalytic subunit (hamTERT). The hamster TERT cDNA encoded 1128 amino acids and shared 64% amino acid identity with human TERT and 80% with murine TERT. As noted with human TERT which express several alternatively spliced mRNAs, we have also detected one alternatively spliced hamTERT mRNA in hamster cancer cells. Transient transfection of hamTERT cDNA in a retroviral expression vector reconstituted telomerase activity in the telomerase negative human lung fibroblast IMR90 cells.

Purpose: This study was undertaken to analyze whether the p53 codon 72 single nucleotide polymorphism might be correlated with the risk and/or the prognosis of cervical cancer in Korean women., Materials and Methods: Peripheral blood samples derived from patients with cervical squamous cell carcinoma (SCC) (n=68), cervical adenocarcinoma (n=37), cervical intraepithelial neoplasia (CIN) III (n=98) and normal controls (n=98) were examined. Germline genomic DNA was extracted from peripheral blood leukocytes and examined by PCR amplification of the specific alleles assay described by Storey et al.5 Statistical analysis was performed using the Chi-Square test or the Kaplan-Meier survival analysis, logistic regression analysis., Results: The proportions of individuals who were homozygous for the proline allele, and heterozygous for the two allele, homozygous for arginine allele in each group were 15%, 47%, 38% in the SCC group; 6%, 7%, 24% in the adenocarcinoma group; 7%, 33%, 60% in the CIN III group; and 11%, 38%, 51% in the control group. No significant difference was found between the three groups (p>0.05). However there was a significant difference in the adenocarcinoma group (p<0.05). Arg/Arg homozygote reduced the risk of adenocarcinoma. No significant difference existed in 5-year survival rates in the three groups (p=0.22 in SCC, p=0.91 in adenocarcinoma)., Conclusion: These findings suggest that Arg/Arg homozygocity of the p53 codon 72 would be a protective factor against the development of cervical adenocarcinoma.

Bacterial biofilms are ubiquitous in nature. Recent studies have demonstrated many unique qualities previously unknown to bacteria and have yielded new insights into relevant dental issues.

In 7,12-dimethylbenz[a]anthracene-treated hamster pouch epithelial cells, telomerase activity increased within 1 week of treatment and reached a 6-7-fold increase within 3 weeks. To investigate this phenomenon, we have cloned and sequenced the hamster telomerase catalytic subunit (hamTERT) promoter. Transient transfection with different genomic segments upstream of the ATG translation initiation codon linked to the luciferase reporter gene mapped the core promoter within a 250 bp region. Three major transcription initiation sites and several minor sites were found between -42 and -140 bp relative to the ATG site. Like the human and murine TERT promoters, the hamTERT promoter lacks TATA and CAT boxes and all three promoters share similar regulatory factor binding sites. DNase I footprint analysis revealed six protected regions which contain sequences homologous with known transcription factor binding sites. Three protein binding regions (I, II, and III) were essential for the promoter activity. Regions I and III bound to Sp1 and Sp3 transcriptional factors, whereas region II bound to an unknown factor. Transient transfection of a promoter-luciferase plasmid into Drosophila SL2 cells showed that Sp1 and Sp3 regulated the hamster TERT promoter in a concentration-dependent and synergistic manner. Telomerase activity showed a 2-4-fold and 8-10-fold increase in immortalized cells and tumor cells, respectively, but hamTERT expression was only increased 1.7-fold and 2.4-fold, respectively, in the same cells.

Normal somatic cells terminate their replicative life span through a pathway leading to cellular senescence, which is triggered by activation of p53 and/or pRb in response to critically shortened telomere DNA. Potentially neoplastic cells must first overcome the senescence checkpoint mechanisms and subsequently activate telomerase to propagate indefinitely. Although telomerase activation is closely associated with cellular immortality, telomerase alone is not sufficient to warrant tumorigenicity. Environmental factors, including chemical carcinogens and viral infection, often contribute to aberrant changes leading to tumorigenic conversion of normal cells. Of particular importance in oral cancer development are tobacco-related chemical carcinogens and human papillomavirus (HPV) infection. To describe the molecular mechanisms by which these environmental factors facilitate the genesis of oral cancer, we first established an in vitro multistep oral carcinogenesis model by sequential exposure of normal human oral keratinocytes (NHOK) to "high risk" HPV and chemical carcinogens. Upon introduction of the HPV genome, the cells bypassed the senescence checkpoint and entered into an extended, but not immortal, life span during which telomere DNA continued to shorten. In a few immortal clones surviving beyond the crisis, we found a marked elevation of telomerase activity and stabilization of telomere length. Furthermore, the E6 and E7 oncoproteins of "high risk" HPV disrupted the cell cycle control and DNA repair in immortalized HOK, and enhanced mutation frequency resulting from genomic instability. However, HPV infection alone failed to give rise to a tumorigenic cell population, which required further exposure to chemical carcinogens in addition to HPV infection. Analysis of the data presented suggests that oral carcinogenesis is a series of discrete genetic alterations that result from a continued genotoxic challenge by environmental risk factors. Our in vitro model may be useful for investigators with interest in furthering our understanding of oral carcinogenesis.

Objective: It has recently been suggested that white women who are homozygous for the allele of the gene for wild-type p53 protein (TP53) that encodes arginine at position 72 are more susceptible to human papillomavirus-associated cervical carcinoma than are women who are heterozygous for this polymorphism and women who are homozygous for the allele that encodes proline at that position. This study was undertaken to analyze whether the TP53 codon 72 single-nucleotide polymorphism might be correlated with the risk of cervical cancer among Korean women., Study Design: Peripheral blood samples from patients with invasive cervical carcinoma yielding a positive result for human papillomavirus 16 (n = 100), patients with cervical intraepithelial neoplasia grade III (n = 134), and healthy control subjects (n = 100) were examined. The presence and genotype of human papillomavirus in cancerous cervical tissues were determined by E6, E7-based nested polymerase chain reaction. Germline genomic deoxyribonucleic acid was extracted from peripheral blood leukocytes and examined by polymerase chain reaction amplification of the specific allele assay as described by Storey et al. Deoxyribonucleic acid samples from patients whose TP53 sequences had been determined by direct sequencing were used as positive control preparations., Results: The respective proportions of individuals who are homozygous for the arginine allele, homozygous for the proline allele, and heterozygous for the 2 alleles were 40%, 12%, and 48% among women with invasive cervical carcinoma, 52%, 9%, and 39% among women with cervical intraepithelial neoplasia grade III, and 52%, 11%, and 37% among the control group. No significant differences in the frequency of codon 72 alleles were found among the 3 groups (chi(2) = 4.414; P =.353; degrees of freedom = 4)., Conclusion: This finding suggests that the risk of cervical cancer may not be increased for Korean women with the allele of TP53 encoding arginine at codon 72.

CD4(-) epithelial cells covering mucosal surfaces serve as the primary barrier to prevent human immunodeficiency virus type 1 (HIV-1) infection. We used HIV-1 vectors carrying the enhanced green fluorescent protein gene as a reporter gene to demonstrate that HIV-1 can infect some CD4(-) human epithelial cell lines with low but significant efficiencies. Importantly, HIV-1 infection of these cell lines is independent of HIV-1 envelope proteins. The Env-independent infection of CD4(-) cells by HIV-1 suggests an alternative pathway for HIV-1 transmission. Even on virions bearing Env, a neutralizing antibody directed against gp120 is incapable of neutralizing the infection of these cells, thus raising potential implications for HIV-1 vaccine development.

The replication kinetics and cytological changes of normal human oral keratinocytes (NHOK) isolated from the basal surface of oral epithelial sheet and cultured as dispersed cells in low (0.15 mM) Ca(2+) medium without serum were analyzed. Replicating NHOK were quantitated by cell count and identified by [(3)H]thymidine uptake. Cell morphology was analyzed by phase contrast and transmission electron microscopy, and by cytochemical staining for endogenous beta-galactosidase (beta-gal) activity, involucrin, and cytokeratin types 1 and 10 (K1/K10). Primary NHOK obtained from 15 different donors whose ages ranged from 21 to 62 years consistently showed three distinct phases of replication, i.e., exponential, senescing, and senescent, which were independent of the donors' age. Initially, the cells replicated exponentially for a period of 20 days with a doubling time of 26.6 +/- 3.5 h. They then gradually entered replication arrest over a period of 18 days. The cells underwent a maximum of 22.1 +/- 2.8 population doublings. The onset of gradual replication arrest coincided with an increase in the fraction of cells, which stopped DNA synthesis within a maximum of 48 h and which stained for beta-gal. The fraction of terminally differentiated cells stained for K1/K10 did not increase until nearly all the cells had stopped replicating (senescent phase) and maximal beta-gal staining had been reached. Subsequently, the percentage of beta-gal stained cells actually decreased while the percentage of those stained for K1/K10 increased to a maximum of 80-90% within 2-3 weeks. Exposure of exponentially replicating NHOK to 5-aza-2'-deoxycytidine (5-aza CdR) inhibited DNA replication within 18-48 h and induced terminal differentiation 6 days later. In contrast, exposure of these cells to 1.5 mM Ca(2+) induced expression of involucrin and K1/K10 within 48 h without inhibiting DNA synthesis. Thus, replication arrest preceded differentiation in NHOK serially subcultured in vitro; however, differentiation could be induced without replication arrest., (Copyright 2000 Academic Press.)

c-Jun N-terminal kinase (JNK) regulates gene expression in response to various extracellular stimuli. JNK can be activated by the tumor promoting agent, 12-O-tetradecanoylphorbol-13-acetate (TPA) in normal human oral keratinocytes but not in human keratinocytes that have been immortalized (HOK-16B and HaCaT) or transformed (HOK-16B-Bap-T) nor in a cervical carcinoma cell line (HeLa). The refractory JNK activation response to TPA is not due a defect in the JNK pathway, because JNK can be activated by other stimuli, e.g. UV irradiation and an alkylating agent N-methyl-N'-nitrosoguanidine in these immortalized or transformed cells. More importantly, the refractory JNK and JNKK activation response to TPA can be restored by treatment of the cells with a combination of TPA and a protein-tyrosine phosphatase inhibitor, sodium orthovanadate. Furthermore, pretreatment of cells with TPA partially inhibited UV- or N-methyl-N'-nitrosoguanidine-induced JNK activity. These results suggest that a TPA-inducible, orthovanadate-sensitive protein-tyrosine phosphatase may specifically down-regulate JNK signaling pathway in these immortalized/transformed epithelial cells. In contrast, ERK and p38/Mpk2 are not regulated by this TPA-induced phosphatase. This putative protein-tyrosine phosphatase appears to be JNK pathway-specific.

Gene amplification is a common feature of tumors. Overexpression of some amplified genes plays a role in tumor progression. Gene amplification can occur either extrachromosomally as double-minute chromosomes (dmin) or intrachromosomally in the form of homogeneously staining regions (hsrs). Approximately one-half of our oral squamous cell carcinomas (OSCCs) are characterized by amplification of band 11q13, usually as an hsr located entopically (occurring or situated at the normal chromosomal site, as opposed to ectopically). Using chromosomal fluorescence in situ hybridization (FISH), we confirmed the amplification of the cyclin D1 (CCND1/PRAD1) and fibroblast growth factor types 3 and 4 (FGF3/INT2 and FGF4/HSTF1) genes within the 11q13 amplicon in our series of primary OSCCs and derived cell lines. The human RIN1 gene was isolated as an RAS interaction/interference protein in a genetic selection in yeast and has been described as a putative effector of both the RAS and ABL oncogenes. We mapped RIN1 to 11q13.2. FISH analysis of 10 11q13-amplified OSCC cell lines revealed high-level RIN1 amplification in two cell lines. Three additional cell lines have what appear to be duplications and/or low-level amplification of RIN1, visible in both interphase and metaphase cells. The hybridization pattern of RIN1 on the metaphase chromosomes is particularly revealing; RIN1 signals flank the 11q13 hsr, possibly as a result of an inverted duplication. The gene amplification model of Coquelle et al. (1997) predicted that gene amplification occurs by breakage-fusion-bridge (BFB) cycles involving fragile sites. Our data suggest that the pattern of gene amplification at 11q13 in OSCC cell lines is consistent with a BFB model. RIN1 appears to be a valuable probe for investigating the process of gene amplification in general and, specifically, 11q13 amplification in oral cancer.

The E7 oncoprotein encoded by human papillomavirus (HPV) type 16 repressed the transcription of fibronectin, a key component of the extracellular matrix. This repression, detected in several HPV-positive nontumorigenic and tumorigenic cell lines, was abolished when the Cys-X-X-Cys repeats in E7 were disrupted.

We report here that E7 oncoprotein of human papillomavirus type 16 (HPV-16) forms a complex in vivo and in vitro with actin, one of the components of the cellular cytoskeleton. The in vivo interaction was detected by immunofluorescent staining and confocal microscopic examination of normal human oral keratinocytes (NHOK) and CV-1 cells after transient expression of E7 employing the vaccinia virus-T7 RNA polymerase system and by coimmunoprecipitation from an immortalized, nontumorigenic cell line obtained after transfecting NHOK with the cloned HPV-16 DNA genome. The in vitro interaction was detected by cosedimentation of bacterially expressed E7 phosphorylated with rabbit reticulocyte lysate or purified casein kinase II (CKII) prior to incubation with F-actin. This interaction was inhibited if E7 phosphorylation by the rabbit reticulocyte lysate was prevented with heparin, a CKII inhibitor, or if the amino acids Ser-31 and Ser-32 in E7, which are phosphorylated by CKII, were replaced with amino acids that cannot be phosphorylated. Interestingly, a decrease in the amount of polymerized actin occurred in cells expressing E7., (Copyright 2000 Academic Press.)

We previously reported that 'high risk' human papillomaviruses (HPV) induce genetic instability in human oral keratinocytes. To understand the mechanisms of HPV-induced genetic instability, we determined the nucleotide excision repair (NER) capacity of normal (NHOK) and human papillomavirus type-16 immortalized oral keratinocytes (HOK-16B) by strand-specific removal of UV-induced cyclobutane pyrimidine dimers (CPDs) from a 16 Kb fragment of the p53 gene. In NHOK the NER activity was initiated in both DNA strands immediately, although the process in the non-transcribed strand was notably slower than that of the transcribed strand. In HOK-16B cells the initiation of CPDs removal was delayed for at least 8 h in both DNA strands, and the process was significantly slower than that in NHOK. UV-irradiation enhanced the p53 protein level more than 30-fold in NHOK, but it did not significantly alter the protein level in the HOK-16B cells. UV-irradiation also increased the p21WAF1/CIP1 protein level only in NHOK. These data indicate that 'high risk' HPV induces genetic instability by impairing NER capacity of cells. Impaired NER activity of HOK-16B cells may be implicated with their inability to enhance active p53 when challenged by genotoxic stress.

Subculture of primary normal human oral keratinocytes (NHOK) results in terminal differentiation, leading to cell death. To investigate whether the subculture-induced death of NHOK is due to apoptosis, we studied transferase-mediated dUTP nick end labeling (TUNEL)-positive cells, DNA fragmentation, and expression of several apoptosis-associated genes from NHOK with different passage numbers. We also determined the effect of transforming growth factor beta1 (TGF-beta1) on the induction of apoptosis in NHOK. We were able to subculture primary NHOK up to the fifth passage, at which point cells showed morphological features of differentiation. Appearance of DNA fragmentation concurrently occurred with an increase in the number of TUNEL-positive cells with higher passage numbers. The level of cellular p53 proteins was gradually decreased by the continued passage of cells, whereas the levels of intracellular and secreted TGF-beta and phospholipase C-gamma1 (PLC-gamma1) were significantly elevated by serial subculture. Exogenous TGF-beta1 also induced differentiation and apoptosis of proliferating NHOK. These data indicate that terminal differentiation of NHOK is associated with apoptosis, which is, in part, linked to elevated cellular levels of TGF-beta and PLC-gamma1., (Copyright 1999 Academic Press.)

Endodermal sinus tumor (EST) is a rare neoplasm which usually arises in the testis or ovary. But extragonadal EST is well recognized and may arise in a wide array of sites such as the mediastinum, vagina, and brain. We report a case of primary EST of the omentum and to our knowledge it is the first case of omental EST in the literature. A 45-year-old woman with a history of abdominal distension was treated with total abdominal hysterectomy with bilateral salpingo-oophorectomy and infracolic omentectomy, followed by four cycles of BEP (bleomycin, etoposide, cisplatin) combination chemotherapy. Microscopically, the tumor exhibited typical patterns of EST and stained for alpha-fetoprotein and cytokeratin. She has remained free of disease for 10 months of follow-up. According to previous studies, debulking surgery and BEP chemotherapy were used as primary therapy with good results. The subject of extragonadal EST is reviewed, and the possible histogenesis of this tumor at such a rare site is discussed., (Copyright 1999 Academic Press.)

Superoxide and H2O2 production by neutrophils stimulated by 0.5 mg/ml degraded immunoglobulin G (IgG) and 1 microM N-formyl-methionyl-leucyl-phenylalanine (fMLP) was inhibited by ambroxol in a dose-dependent fashion, and at the concentration of 100 microM, 43.3% to 64.3% of inhibitions were detected. The inhibitory effect of ambroxol on H2O2 production by neutrophils was greater than that on superoxide production. The production of nitrite by lipopolysaccharide-activated murine peritoneal macrophages was significantly attenuated by ambroxol in a dose-dependent fashion and NG-monomethyl-L-arginine (NMMA). Ambroxol decreased the release of myeloperoxidase and lysozyme evoked by 0.5 mg/ml degraded immunoglobulin G and 1 microM fMLP in a dose-dependent fashion, and at the concentration of 100 microM, 37.1% to 64.2% of inhibitions were observed. The stimulatory effect of phorbol 12-myristate 13-acetate (PMA) (0.1 microg/ml) on superoxide production and myeloperoxidase, which is inhibited by 100 nM staurosporine, was not affected by 100 microM ambroxol. Degraded immunoglobulin G (0.5 mg/ml) caused an immediate elevation of [Ca2+]i in fura-2 load neutrophils in 1.23 mM Ca2+-containing medium. Preincubation of neutrophils with 10 microM to 100 microM ambroxol, 5 mM EGTA and 100 microM verapamil depressed the elevation of [Ca2+]i elicited by 0.5 mg/ml degraded immunoglobulin G. In conclusion, the inhibitory action of ambroxol on stimulated neutrophil responses, including respiratory burst and lysosomal enzyme release, appears to be attributed to its depressant action on the activation process, including the change in intracellular Ca2+ level. in which the role of protein kinase C is uncertain.

We have previously demonstrated that normal human oral keratinocytes immortalized by transfection with human papillomavirus type-16 Dna became tumorigenic after exposure to a chemical carcinogen. In an effort to detect differentially regulated genes associated with this transition from the immortal to the malignant phenotype, we employed representational differences analysis (a PCR-coupled subtractive hybridization technique). After analysing 50 colonies, 12 putative messages were identified. Northern analysis comparison using the identified cDNAs as probes was made between normal human oral keratinocyte, papillomavirus-immortalized human oral keratinocytes (HOK-16B), a neoplastic cell line derived from HOK-16B (HOK-16B-BaP-T) and the human oral cancer cell lines Hep-2, SCC-9 and Tu-177. We found that mRNAs encoding for cyclophilin A, c-myc binding protein 1, the heat shock protein 90alpha and one unknown transcript were up-regulated in the oral cancer cell lines analysed as well as in HOK-16B cells. We also detected a downregulation of the mRNAs encoding the skin-derived antileukoproteinase SKALP/elafin, the translationally regulated p23 protein and one unknown transcript. Whether these messages are associated to the neoplastic conversion of human keratinocytes remains to be determined.