Decreasing cytokeratin 17 expression in head and neck cancer predicts nodal metastasis and poor prognosis: The first evidence.

OBJECTIVES: Cytokeratins (CKs) are mainly expressed in epithelial carcinomas and are valuable for making diagnoses and identifying metastatic status. Changes in the expression of individual CKs in certain carcinoma may be relevant to establishing a prognosis. However, the prognostic significance of CKs in head and neck squamous cell carcinoma (HNSCC) remains elusive. Herein, we investigated the diverse and unique expression patterns of Cytokeratin 13 (CK13) and Cytokeratin 17 (CK17) and assessed the role of CK17 as a predictor for HNSCC metastasis and prognosis. METHODS: CK13 and CK17 expressions were evaluated using immunohistochemical tissue microarray (TMA) analysis with 106 patients of HNSCC. To clarify the characterisation of CK17 expression with respect to its ability in predicting metastatic disease, an in vitro study of cells migration/invasion assays was conducted. Furthermore, the correlation of CK17 expression to clinicopathologic variables and prognosis was analyzed using a serial statistical method. RESULTS: CK13 was predominately expressed in non-cancerous tissues and was lost in HNSCC. Decreasing expression of CK17 correlated with cancerous cell migration and invasion (P < .0001) in an in vitro study. CK17 expression was lower in the N1 and N2 nodal metastases category compared to the N0 stage. Moreover, Kaplan-Meier survival analyses showed that a lower CK17 expression was associated with a poorer survival connotation in HNSCC patients (P < .05) with 10-year follow-up. CONCLUSION: Our findings provide the first evidence that CK17 under-expression might be a potential predictor of nodal metastasis and adverse prognosis.

Secondary prophylaxis treatment versus on-demand treatment for patients with severe haemophilia A: comparisons of cost and outcomes in Taiwan.

This study compared secondary prophylaxis treatment with on-demand treatment for severe haemophilia A in Taiwan. Fifty patients from one medical centre were evaluated over a 5-year period. Differences in annual bleed rates and factor VIII (FVIII) utilization were assessed between patients receiving secondary prophylaxis and patients receiving FVIII concentrates on-demand. Results were then used as inputs in a pharmacoeconomic model to predict outcomes of future haemophilia therapy strategies in Taiwan. The median annual number of total bleeding episodes was significantly lower in the 13 (26%) patients who received secondary prophylaxis than in the 37 patients who received FVIII on-demand (7.76 vs. 31.91, P < 0.0001). The between-group difference in median annual factor VIII utilization was statistically significant (1824.41 IU kg(-1) for the prophylaxis group and 1324.81 IU kg(-1) for the on-demand group, P < 0.01). It was estimated that approximately $2 million (USD) per year would be added to the cost of treatment by having all severe haemophilia A patients in Taiwan receive secondary prophylaxis instead of on-demand therapy while 12,566 bleeding will be prevented. It is recommended that National Health Insurance officials utilize these data to evaluate the benefits of enhanced treatment strategies and before making substantial policy changes to haemophilia care in Taiwan.

Prognostic factors in pathological stage IB nonsmall cell lung cancer greater than 3 cm.

Significant heterogenity of stage IB (sixth edition of the TNM staging system) nonsmall cell lung cancer (NSCLC) has been identified, and further subclassification according to tumour size has been proposed. The aim of this study is to evaluate the prognostic factors in patients with resected stage IB NSCLC > 3 cm. From January 1980 to December 2000, 525 patients underwent surgical resection for stage IB NSCLC > 3 cm at Taipei Veterans General Hospital, Taipei, Taiwan. The clinicopathological characteristics of these patients were retrospectively reviewed. The 5- and 10-yr overall survival rates were 44.9% and 27.3%, respectively. Age (p < 0.001), tumour size (p = 0.002), extent of pulmonary resection (p = 0.002), histological type (p = 0.005) and number of mediastinal lymph nodes dissected/sampled (p = 0.004) were significant predictors for overall survival in multivariate analysis. Patients with tumour size >7 cm, or > 5 to ≤ 7 cm, had a worse survival than those with tumour size > 3 to ≤ 5 cm. However, visceral pleural invasion did not influence overall survival. Stage IB NSCLC with a diameter > 3 cm may be subclassified according to tumour size regardless of visceral pleural invasion.

Design and implementation of robust controllers for a gait trainer.

This paper applies robust algorithms to control an active gait trainer for children with walking disabilities. Compared with traditional rehabilitation procedures, in which two or three trainers are required to assist the patient, a motor-driven mechanism was constructed to improve the efficiency of the procedures. First, a six-bar mechanism was designed and constructed to mimic the trajectory of children's ankles in walking. Second, system identification techniques were applied to obtain system transfer functions at different operating points by experiments. Third, robust control algorithms were used to design Hinfinity robust controllers for the system. Finally, the designed controllers were implemented to verify experimentally the system performance. From the results, the proposed robust control strategies are shown to be effective.

Rat liver ischemia/reperfusion induced proinflammatory mediator and antioxidant expressions analyzed by gene chips and real-time polymerase chain reactions.

OBJECTIVE: Ischemia/reperfusion (I/R) of the rat liver induces injury; however, few studies have investigated gene expressions associated with this phenomenon. In this study, gene chip and real-time polymerase chain reactions (PCR) were used to study the expressions of the proinflammatory mediators and antioxidants after I/R. MATERIALS AND METHODS: Ischemia was induced by clamping the common hepatic artery and portal vein for 40 minutes followed by 90 minutes reperfusion. Blood samples collected before ischemia and after reperfusion were analyzed for alanine amino transferase, lactic dehydrogenase, hydroxyl radicals, nitric oxide (NO), and tumor necrosis factor alpha (TNFalpha). Expressions of TNFalpha, interleukin 12 (IL12), cyclooxygenase II (COXII), and other inflammatory mediators were analyzed by gene chips. COXII, TNFalpha, and antioxidants of mitochondrial superoxide dismutase (SOD(Mn)), catalase, and heat shock protein 70 (HSP70) were double confirmed by real-time PCRs. RESULTS: This protocol resulted in elevations in the blood concentrations of NO, hydroxyl radicals, TNFalpha, ALT, and LDH (P < .01) in the I/R but not the sham-operated group. Reperfusion induced significant increases in the expressions of TNFalpha, IL12, COXII, SOD(Mn), catalase, and HSP70. Real-time PCR also demonstrated increases in mRNA expressions of the proinflammatory mediators and antioxidants. CONCLUSIONS: This protocol resulted in oxidative stress, nitrosative stress, and liver injury. The increases in expressions of both proinflammatory mediators and antioxidants suggested that an imbalance between inflammation and anti-inflammation could be the possible reason for the liver injury after I/R.

A link between increased transforming activity of lymphoma-derived MYC mutant alleles, their defective regulation by p107, and altered phosphorylation of the c-Myc transactivation domain.

The c-Myc protein is a transcription factor with an N-terminal transcriptional regulatory domain and C-terminal oligomerization and DNA-binding motifs. Previous studies have demonstrated that p107, a protein related to the retinoblastoma protein, binds to the c-Myc transcriptional activation domain and suppresses its activity. We sought to characterize the transforming activity and transcriptional properties of lymphoma-derived mutant MYC alleles. Alleles encoding c-Myc proteins with missense mutations in the transcriptional regulatory domain were more potent than wild-type c-Myc in transforming rodent fibroblasts. Although the mutant c-Myc proteins retained their binding to p107 in in vitro and in vivo assays, p107 failed to suppress their transcriptional activation activities. Many of the lymphoma-derived MYC alleles contain missense mutations that result in substitution for the threonine at codon 58 or affect sequences flanking this amino acid. We observed that in vivo phosphorylation of Thr-58 was absent in a lymphoma cell line with a mutant MYC allele containing a missense mutation flanking codon 58. Our in vitro studies suggest that phosphorylation of Thr-58 in wild-type c-Myc was dependent on cyclin A and required prior phosphorylation of Ser-62 by a p107-cyclin A-CDK complex. In contrast, Thr-58 remained unphosphorylated in two representative mutant c-Myc transactivation domains in vitro. Our studies suggest that missense mutations in MYC may be selected for during lymphomagenesis, because the mutant MYC proteins have altered functional interactions with p107 protein complexes and fail to be phosphorylated at Thr-58.

Nm23H1 mediates tumor invasion in esophageal squamous cell carcinoma by regulation of CLDN1 through the AKT signaling.

Esophageal cancer is a lethal malignancy worldwide. Previously, low expression of metastasis suppressor Nm23H1 and tight junction (TJ) protein claudin-1 (CLDN1) have been known to correlate with poor prognosis in esophageal squamous cell carcinoma (ESCC). However, the molecular interaction between them has not been clarified. In the present study, we first examined the expression of Nm23H1 and CLDN1 in 74 surgical ESCC samples by immunohistochemistry (IHC) to verify their clinicopathologic significance. The biologic effects of Nm23H1 gene silencing or overexpression in ESCC cell lines were then studied by migration and invasion studies, and its regulation on CLDN1 expression was also investigated by western blot analysis. Moreover, the expression of Nm23H1 and CLDN1 at the same invasion front of ESCC tumors was verified by immunofluorescence. The results showed a significantly positive correlation between the expression of Nm23H1 and CLDN1 (γ=0.296, P=0.011) in surgical specimens, especially for the 34 tumors with lymph-node metastasis (γ=0.455, P=0.007). In ESCC cell lines, silencing of Nm23H1 expression markedly enhanced cell invasiveness, accompanied by increased Akt phosphorylation and decreased CLDN1 expression. Conversely, Nm23H1-expressed transfectants exhibited reduced invasiveness, decreased Akt phosphorylation and correspondingly increased CLDN1 expression. Regain of CLDN1 expression in ESCC cells significantly suppressed invasiveness, but did not influence the Akt phosphorylation. Moreover, treating Nm23H1-depleted cells with the AKT inhibitor MK2206 recovered CLDN1 expression, and diminished the invasiveness of ESCC cells. Finally, decreased expressions of both CLDN1 and E-cadherin were observed at the invasive front of the Nm23H1-negative tumors. Overall, our current study documented that reduced Nm23H1 expression activates the AKT signaling pathway, results in diminished CLDN1 expression and potentiates invasiveness of ESCC cells. Enhancement of Nm23H1 expression, inhibition of the AKT signaling pathway, or combined, might be a potential treatment strategy in selective ESCC patients.

MR of the cerebral operculum: topographic identification and measurement of interopercular distances in healthy infants and children.

PURPOSE: To evaluate the role of axial, coronal, and sagittal MR in identification of surface landmarks of the cerebral operculum and to determine the reference values of interopercular distances of each hemisphere in healthy infants and children on MR images. METHODS: Two hundred fourteen cerebral opercula of 35 healthy infants and 72 healthy children were retrospectively evaluated from 107 routine MR brain examinations. The surface landmarks of the operculum and interopercular distances of each hemisphere, which were subjectively divided into anterior interopercular distance (anterior sylvian width) and posterior interopercular distance (posterior sylvian width), were recorded from axial, coronal, and sagittal MR images, respectively. The mean value of anterior interopercular distance of each hemisphere was obtained by averaging two linear measurements of the anterior sylvian width from lateral, sagittal, and axial planes of the same side. Likewise, the posterior interopercular distance of each side of the brain was obtained from averaging of two measurements on lateral, sagittal, and coronal planes. RESULTS: The landmarks of the operculum were best identified by sagittal MR, followed by axial and coronal images. The average values of left anterior interopercular distance, right anterior interopercular distance, left posterior interopercular distance, and right posterior interopercular distance in infants were 1.9 +/- 1.3, 1.6 +/- 1.1, 0.4 +/- 0.7, and 0.2 +/- 0.4 mm, and in children, 0.9 +/- 1.3, 1.0 +/- 1.4, 0.03 +/- 0.23, and 0.01 +/- 0.07 mm, respectively. Infants showed significantly wider interopercular distances than children. Left anterior interopercular distance was significantly wider than right in infants, but not in children. Male children displayed a more significant increase in anterior interopercular distance than did female children. There was no statistic difference in measurements of anterior interopercular distance and posterior interopercular distance between female and male infants. CONCLUSIONS: The operculum should be evaluated with MR in three planes. Infants may show conspicuous sylvian fissures that should not exceed 4.5 mm (mean + 2 SD) anteriorly on axial and sagittal planes and 1.8 mm posteriorly on sagittal and coronal planes. Healthy children who have fully developed opercula should have an anterior interopercular distance of no more than 3.5 mm and a posterior interopercular distance of 0.5 mm.

MR of the cerebral operculum: abnormal opercular formation in infants and children.

PURPOSE: To evaluate abnormalities of the cerebral operculum in infants and children and to propose the embryogenic basis of abnormal opercular formation as determined from MR imaging findings. METHODS: Eighty-six infants and children who had abnormally wide interopercular distances and/or distorted opercular topography seen on MR images were studied retrospectively. Clinically, patients presented with tonal abnormalities, macrocephaly, microcephaly, seizures, developmental delay, cerebral palsy, or facial dysmorphism. The abnormal opercula were compared with developing opercula at different stages of gestation. RESULTS: Among the 86 infants and children, two categories of opercular abnormalities were identified: an underdeveloped operculum (n = 64) and a malformed operculum (n = 22). The malformed operculum was further classified into three subtypes: nonformation of the operculum with lissencephaly (n = 1, 1%), abnormal opercular formation with pachygyria (n = 11, 13%), and nonformation or abnormal formation of the operculum without pachygyria or lissencephaly (n = 10, 12%). Two subtypes of the underdeveloped operculum were identified: an open operculum without a normal insula (n = 6, 7%) and an open operculum with a normal insula (n = 58, 67%). The five subtypes of abnormal opercular configuration showed a range of maturity that was comparable to the developing operculum at different ages. CONCLUSION: Opercular anomalies appear to follow sequentially predetermined normal steps in development. Arrest in opercular development or malformation may occur after an initial insult. MR imaging is the method of choice by which to identify these abnormalities.

Childhood leukemia: central nervous system abnormalities during and after treatment.

PURPOSE: To document the radiologic abnormalities seen in the central nervous system (CNS) during and after treatment of childhood leukemia. METHODS: MR images (19 patients) and CT scans (12 patients) were reviewed retrospectively in 19 children and adolescents with neurologic complications of leukemia or its treatment. Patients were divided into two groups: the first included those with disease-related complications of leukemia, such as meningeal and parenchymal leukemia, chloroma, and cerebrovascular disorders; the second included patients with treatment-related neurotoxicity and infection caused by immunocompromised states. Pathologic confirmation of the CNS lesions was obtained in eight patients. Factors that predisposed to the development of tumor-related or treatment-related complications were determined by reviewing the medical records. RESULTS: Among the 19 patients, 10 had two or more different CNS abnormalities found on CT scans or MR images. The imaging abnormalities seen in 12 patients during treatment included sinus thrombosis (n = 3), transient gray or white matter ischemia (n = 2), presumed disseminated microinfarcts (n = 1), cerebral hemorrhage or infarct (n = 3), inflammatory demyelinating polyradiculoneuropathy (n = 1), infections (n = 4, 2 bacterial and 2 fungal), and meningeal leukemia (n = 2). After therapy, seven patients had CNS imaging abnormalities, including secondary brain tumors (2 malignant gliomas and 1 CNS lymphoma), spinal chloroma (n = 1), necrotizing leukoencephalopathy and mineralizing microangiopathy (n = 3), cerebral mucormycosis (n = 1), spontaneous intracranial hemorrhage (n = 3), and spinal meningeal leukemia (n = 1). CONCLUSION: The wide spectrum of CNS abnormalities that occur during and after treatment for leukemia is related to the inherent risk of the leukemia itself, to the treatment method, and to the duration of survival. Because many neurologic complications of leukemia are treatable, early diagnosis is essential.

Cerebral MR manifestations of Pompe disease in an infant.

We present the cerebral MR findings of a 5-month-old girl with biopsy-proved Pompe disease and discuss the imaging characteristics with known central nervous system disease.

Rapid spongiform degeneration of the cerebrum and cerebellum in Creutzfeldt-Jakob encephalitis: serial MR findings.

We report the cerebral MR imaging findings in a patient with pathologically proved Creutzfeldt-Jakob disease in whom predominant gray and white matter degeneration was seen within 1 year of symptom onset. The initial MR signal abnormalities in the basal ganglia were subtle. A follow-up MR examination revealed diffuse cerebral and cerebellar atrophy and demyelination.

O-linked N-acetylglucosamine and cancer: messages from the glycosylation of c-Myc.

Altered protein glycosylation is known to correlate with tumorigenesis, but its role remains enigmatic. Cells transformed by altered oncogene or tumor suppressor gene expression often also show changes of carbohydrate on cell surface glycoconjugates which correlate with the potential for tumor invasion and metastasis. In recent years, many oncogene and tumor suppressor gene products, such as c-Myc, SV40 large T antigen, and p53, were shown to be modified by O-GlcNAc. O-GlcNAc is a form of protein glycosylation found almost exclusively in the nucleus and cytoplasm of eukaryotic cells. The known O-GlcNAc-bearing proteins are phosphoproteins and form reversible multimeric complexes. O-GlcNAc modification is dynamic and appears to have a reciprocal relationship with protein phosphorylation. The enzymes which catalyze O-GlcNAc addition and removal have been characterized and used as effective tools in O-GlcNAc studies. It is of great interest in the future to investigate the alteration of O-GlcNAc in different cancers since addition/removal of O-GlcNAc on oncoproteins, tumor suppressor proteins, and other tumor-related proteins very likely plays a key role in the pathogenesis of tumors.

Ultrasonography for inguinal hernias in boys.

BACKGROUND/PURPOSE: History taking and physical examination alone no longer meet the surgeon's need in the diagnosis of inguinal hernia. Ultrasonography (US) provides a good and safe diagnostic tool for inguinal hernias in boys. METHODS: From 1995 to 1997, 244 boys with inguinal hernias (41 bilateral and 203 unilateral), received preoperative US on both groins to confirm the diagnosis. Those with positive US findings, such as viscera or fluid in inguinal canal or widening of the internal inguinal ring, underwent surgery. RESULTS: The accuracy of diagnosis with US and clinical assessment were 97.9% and 84%, respectively. More than 95% of widening of internal inguinal rings (>4 mm) proved to be hernias. There were two direct inguinal hernias and two femoral hernias, which were misdiagnosed by clinical examination, but proved to be diagnosed correctly by US. CONCLUSIONS: US serves as a noninvasive and highly accurate diagnostic tool for inguinal hernias in boys. Using 4 mm as the upper limit of the normal diameter of the internal inguinal ring, an occult inguinal hernia can be easily detected before surgery.

Well-differentiated fetal adenocarcinoma of the lung.

We describe the case of a 43-year-old woman with a tumor shadow in the upper lobe of the left lung. The tumor was initially suspected to be a carcinoid tumor, following percutaneous needle biopsy. Subsequently, a left upper lobectomy was performed, and a well-differentiated fetal adenocarcinoma was diagnosed histologically. Unlike the biphasic epithelial and stromal features of pulmonary blastoma, it was composed solely of malignant glands of embryonal appearance.

New polymeric benzotriazole reagents for off-line derivatizations of amines and polyamines in HPLC.

New polymeric reagents are synthesized, based on a polystyrene-bound benzotriazole containing an o-acetylsalicyl or 9-fluorenyl labelling moiety. This is used in an off-line mode, prior to high performance liquid chromatography (HPLC), for derivatizations of trace primary and secondary amines, polyamines, and related compounds in connection with HPLC. Standards are prepared, characterized by physical and spectral properties, and then used as external standards to determine percent derivatizations. The polymeric reagents are characterized by elemental analyses and loading determinations. The feasibility and applicability of this reagent for derivatization of nucleophiles is confirmed with a number of amines under optimized conditions. The activated labelling moiety, bonded to the polymeric support, makes the derivatization reactions extremely rapid and efficient under mild reaction conditions. This alone provides significant advantages over the analogous solution derivatizations for the same amines. A comparison of solution and solid phase derivatization reactions is reported. The limits of detection are 1 to 2 pmol for polyamines, such as cadaverine, putrescine, and 1,7-diaminoheptane, using the benzotriazole fluorenyl reagent followed by fluorescence detection.

Retinal detachment in U.S. Air Force flyers.

Retinal detachment is a serious ocular condition, even though 85% can be repaired permanently. Long-term complications include decreased or loss of vision, redetachment, visual field changes, and proliferative vitreoretinpathy. To assess the effect of retinal detachment on flying careers, we reviewed the records of all aviators with a rhegmatogenous retinal detachment who were examined by the Ophthalmology Branch of the Aerospace Medicine Directorate at the Armstrong Laboratory (formerly the USAF School of Aerospace Medicine) from 1967-1986. Of the 19 flyers, 12 were returned to flying duties; only 2 were disqualified for ocular reasons alone. In 10 flyers, the detachments were previously undiagnosed. Associated vitreoretinal pathology was common in both eyes (42%). All received some type of treatment. Redetachment occurred in 4 flyers, but the overall final reattachment rate was 95%. Final posttreatment visual acuities were 20/20 or better in 16 flyers. Treatment-induced myopia was common. Many flyers enjoyed long flying careers after detachment repairs.

Association of p21 with NF-YA suppresses the expression of Polo-like kinase 1 and prevents mitotic death in response to DNA damage.

Polo-like kinase 1 (PLK1) is an important mitotic kinase and its expression is tightly regulated in the cell cycle and in the DNA damage response. PLK1 expression is previously shown to be suppressed by p53 and/or p21. Here, we demonstrate that the CCAAT box in the PLK1 promoter is pivotal for p53/p21-mediated PLK1 repression. Chromatin immunoprecipitation showed that cyclin-dependent kinase 2 (CDK2) associated with the CCAAT box-containing region of PLK1 promoter in unstressed cells, whereas adriamycin (ADR) induced the recruitment of p21 with a concomitant reduction in the occupancy of CDK2 in this region. Expression of p21 inhibited the interaction between CDK2 and the nuclear factor YA (NF-YA) subunit of the CCAAT box-binding transcription factor NF-Y. A mutant p21 that is defective in CDK2 binding was unable to disrupt the CDK2-NF-YA interaction or suppress PLK1 transcription. Co-immunoprecipitation experiments demonstrated the interaction between NF-YA and p21, and in vitro assays showed that p21 could directly bind to NF-YA. Knockdown of NF-YA decreased the amount of PLK1 promoter-associated p21 and abolished p21-mediated PLK1 repression in cells treated with ADR. Depletion of NF-YA diminished the p53-regulated transcriptional activation and suppressed the p53-mediated protection from mitotic death after DNA damage, and these effects of NF-YA deletion were alleviated by PLK1 depletion. Our findings have uncovered a novel p21/NF-YA/PLK1 axis critical for maintaining the checkpoint function of p53 to prevent mitotic death in the DNA damage-induced response.

Tumoral presence of human cytomegalovirus is associated with shorter disease-free survival in elderly patients with colorectal cancer and higher levels of intratumoral interleukin-17.

Infectious diseases are closely related to cancer. Human cytomegalovirus (HCMV) has been implicated in the promotion of tumour growth, and is present in the tumour specimens of colorectal cancer (CRC). This study aimed to investigate whether tumoral presence of HCMV is associated with a different clinical outcome in elderly patients with CRC. We analysed archived tumour specimens from 95 CRC patients aged ≥65 years. HCMV was detected by PCR. Clinical, pathological, disease-free and overall survival data were compared between patients with HCMV-positive and HCMV-negative tumours. A quantitative RT-PCR array was used to evaluate the expression levels of cytokines genes of T-helper subpopulations in tumours. In the Kaplan-Meier analysis of the 81 patients who underwent curative surgery, 39 patients with HCMV-positive tumours had a lower disease-free survival rate (p 0.024). For patients with stage II or stage III tumours, tumoral HCMV status correlated with disease-free survival more closely than the traditional histopathological staging methods. In a multivariate Cox proportional hazard model, tumoral presence of HCMV independently predicted tumour recurrence in 5 years (hazard ratio 4.42; 95% CI 1.54-12.69, p 0.006). The qRT-PCR analysis of ten stage II tumours showed that the gene expression levels of interleukin-17-the signature cytokine of T-helper 17 cells-and its receptor, interleukin-17 receptor C, were higher in the five HCMV-positive tumours. Our results suggest that the presence of HCMV in CRC is associated with poorer outcome in elderly patients. How the virus interacts with the tumour microenvironment should be further investigated.