A case of breast milk-acquired cytomegalovirus infection in an extremely low birth weight infant

INTRODUCTION

Although breast milk is considered the optimal nutrition for infants, it is also the primary cause of postnatal cytomegalovirus (CMV) infection. Preterm infants with postnatal CMV infections are susceptible to a variety of life-threatening conditions.

CASE SUMMARY

Twin male infants were delivered via emergency caesarian section at 27 weeks' gestation secondary to maternal complete uterine rupture. The Apgar scores at 1 and 5 min were 1 and 1 for the older twin (Twin A) and 0 and 3 for the younger twin (Twin B). Their birth weights were 1203 g (+ 0.65SD) and 495 g (- 3.79SD) respectively. On day 41, laboratory blood test results for Twin B showed a moderate elevation in C-reactive protein (CRP), thrombocytopenia. CMV quantitative polymerase chain reaction (qPCR) tests in Twin B's urine and blood as well as in the mother's breast milk were positive, but stored, dried umbilical cord CMV qPCR tests were negative. Twin B was diagnosed with a postnatal CMV infection secondary to infected breast milk and ganciclovir was commenced on day 52. Treatment was switched to valganciclovir at 74 days of age, but a negative CMV-DNA level in the blood was not achieved. Postnatal CMV infection in this infant led to an exacerbation of pre-existing bronchopulmonary dysplasia (BPD) and he demised at 182 days of age.

CONCLUSION

Postnatal cytomegalovirus infections may lead to exacerbations of BPD. Early use of raw breast milk in preterm infants should be done with careful consideration of this potential complication.

[Endobronchial hamartoma suspected lung cancer due to false positive of fluorodeoxyglucose-positron emission tomography; report of a case]

A 63-year-old male was referred to our hospital with an abnormal shadow on chest radiography and computed tomography. A transbronchial lung biopsy did not reveal any malignant lesion. A fluorodeoxyglucose-positron emission tomography (FDG-PET) was done for further examination and it revealed positive. Right upper lobectomy was perfomed for both diagnosis and treatment. The pathological diagnosis was endobronchial hamartoma The FDG-PET was false positive because of its atelectasis with obstructive pneumonia

Reactivation from latency displays HIV particle budding at plasma membrane, accompanying CD44 upregulation and recruitment

BACKGROUND

It has been accepted that HIV buds from the cell surface in T lymphocytes, whereas in macrophages it buds into intracellular endosomes. Recent studies, on the other hand, suggest that HIV preferentially buds from the cell surface even in monocytic cells. However, most studies are based on observations in acutely infected cells and little is known about HIV budding concomitant with reactivation from latency. Such studies would provide a better understanding of a reservoir for HIV.

RESULTS

We observed HIV budding in latently infected T lymphocytic and monocytic cell lines following TNF-alpha stimulation and examined the upregulation of host factors that may be involved in particle production. Electron microscopy analysis revealed that reactivation of latently infected J1.1 cells (latently infected Jurkat cells with HIV-1) and U1 cells (latently infected U937 cells with HIV-1) displayed HIV particle budding predominantly at the plasma membrane, a morphology that is similar to particle budding in acutely infected Jurkat and U937 cells. When mRNA expression levels were quantified by qRT-PCR, we found that particle production from reactivated J1.1 and U1 cells was accompanied by CD44 upregulation. This upregulation was similarly observed when Jurkat and U937 cells were acutely infected with HIV-1 but not when just stimulated with TNF-alpha, suggesting that CD44 upregulation was linked with HIV production but not with cell stimulation. The molecules in endocytic pathways such as CD63 and HRS were also upregulated when U1 cells were reactivated and U937 cells were acutely infected with HIV-1. Confocal microscopy revealed that these upregulated host molecules were recruited to and accumulated at the sites where mature particles were formed at the plasma membrane.

CONCLUSION

Our study indicates that HIV particles are budded at the plasma membrane upon reactivation from latency, a morphology that is similar to particle budding in acute infection. Our data also suggest that HIV expression may lead to the upregulation of certain host cell molecules that are recruited to sites of particle assembly, possibly coordinating particle production.

Management of branch duct-type intraductal papillary mucinous tumor of the pancreas based on magnetic resonance imaging

BACKGROUND

We assessed the usefulness of magnetic resonance imaging (MRI) in identifying nonmalignant intraductal papillary mucinous tumors (IPMTs) of the pancreas.

METHODS

Thirty-three patients with branch duct-type IPMT diagnosed by endoscopic retrograde cholangiopancreatography were prospectively examined with magnetic resonance cholangiopancreatography followed by dynamic gadolinium-enhanced MRI examinations, and patients with no findings suggestive of malignancy, including a solid mass, mural nodules, a main pancreatic duct wider than 5 mm in diameter, and stenosis of the main pancreatic duct, were prospectively followed up with sequential MRI examinations once or twice a year.

RESULTS

Twenty-six (79%) patients showed no findings suggestive of malignancy in the initial MRI examination. The diameter (mean +/- standard error) of the main pancreatic duct was 3.9 +/- 0.7 mm and that of the ectatic branch pancreatic duct was 36.0 +/- 9.1 mm. Twenty-three patients were prospectively followed for more than 36 months and 22 of them showed no findings suggestive of malignancy during follow-up periods ranging from 39 to 77 months (mean = 55 months).

CONCLUSION

MRI was useful to identify nonmalignant IPMTs of the branch duct type, and close follow-up observation with serial MRI examinations may be appropriate in the management of such patients.

Site-directed removal of N-glycosylation sites in BST-1/CD157: effects on molecular and functional heterogeneity

Cyclic ADP ribose (cADPR) is a novel second messenger that releases calcium from intracellular calcium stores, but works independently of inositol 1,4,5-trisphosphate. In mammals ADP-ribosyl cyclase function is found in two membrane proteins, CD38 and bone marrow stromal cell antigen 1 (BST-1)/CD157. These enzymes are exposed extracellularly and also possess cADPR hydrolase activity, but an intracellular soluble ADP-ribosyl cyclase has been reported in human T-cells. Previously, a soluble form of BST-1/CD157 (sBST-1), which lacked the glycosylphosphatidylinositol-anchored portion, was expressed by a baculovirus-insect-cell system. In this study, we have purified the sBST-1, and it migrated as two major bands by SDS/PAGE, suggesting that it is post-translationally modified. BST-1 contains four putative N-glycosylation sites. Tunicamycin treatment reduced sBST-1 expression in the culture medium, indicating that N-glycosylation is essential for secretion. Site-directed mutagenesis was performed to generate sBST-1 mutants (N1-N4), each preserving a single N-glycosylation site. N1, N3 and N4 were well secreted into the medium, and were each detected as a single band. Although N3 and N4 retained the ADP-ribosyl cyclase activity, the cADPR-hydrolase activity was retained only in N4. We conclude that N-glycosylation of sBST-1 facilitates the folding of the nascent polypeptide chain into a conformation that is conductive for intracellular transport and enzymic activity. Furthermore a crystal has been obtained using the N4 mutant, but not the wild-type sBST-1. Thus the artificial engineering of N-glycosylation sites could be an effective method to generate homogeneous material for structural studies.

Leakage of energy to the body surface during defibrillation shock by an implantable cardioverter-defibrillator (ICD) system--experimental evaluation during defibrillation shocks through the right ventricular lead and the subcutaneous active-can in canines

The leakage of electrical current to the body surface during defibrillation shock delivery by an implantable cardioverter-defibrillator (ICD) device (the Medtronic Jewel Plus PCD system) was evaluated in 5 dogs. The defibrillation shocks were delivered between the active-can implanted in the left subclavicular region and the endocardial lead placed in the right ventricle at the energy levels of 1, 2, 8, 12, 24 and 34 J. During each delivery, the electrical current leakage from the body surface was measured by electrodes connected to a circuit at 4 recording positions: (A) parallel-subcutaneous (the electrodes were fixed in the subcutaneous tissue of the left shoulder and the right lower chest, and the direction of the electrode vector was parallel to the direction of the defibrillation energy flow); (B) cross-subcutaneous (the electrodes were fixed in the subcutaneous tissue of the right shoulder and the left lower chest, and the vector of the electrodes was roughly perpendicular to the direction of the energy flow); (C) parallel-surface (the electrodes were fixed with ECG paste on the shaved skin surface at the left shoulder and the right lower chest); and (D) surface grounded (the electrodes were fixed on the shaved skin surface at the left shoulder and the left foot, which was grounded). The circuit resistance was set at a variable level (100-5,000 ohms) in accordance with the resistance measured through each canine body. Leakage energies were measured in 750 defibrillation shocks with each circuit resistance in 5 dogs. The leakage energy increased in accordance with the increase of the delivered energy and the decrease of the circuit resistance in all 4 recording positions. When the circuit resistance was set at 1,000 ohms, the leakage energy during shock delivery at 34 J was 32+/-17 mJ at position A, 5+/-9 mJ at B, 10+/-9 mJ at C, and 4+/-3 mJ at D (p=0.042). The peak current was highest at position A and was 87+/-22 mA with a circuit resistance of 1,000 ohms. The power of the leakage energy depended on the delivered energy and the impedance between the electrodes. The angle between the alignment of the recording electrodes and the direction of the energy flow was another important factor in determining the leakage energy. Although the peak current of the leakage energy reached the level of macro shock, the highest leakage energy from the body surface was considerably less because of the short duration of the shock delivery.

Evolution of prokaryotic gene order: genome rearrangements in closely related species

Conservation of gene order in prokaryotes has become important in predicting protein function because, over the evolutionary timescale, genomes are shuffled so that local gene-order conservation reflects the functional constraints within the protein. Here, we compare closely related genomes to identify the rate with which gene order is disrupted and to infer the genes involved in the genome rearrangement.

TAP (NXF1) belongs to a multigene family of putative RNA export factors with a conserved modular architecture

Vertebrate TAP (also called NXF1) and its yeast orthologue, Mex67p, have been implicated in the export of mRNAs from the nucleus. The TAP protein includes a noncanonical RNP-type RNA binding domain, four leucine-rich repeats, an NTF2-like domain that allows heterodimerization with p15 (also called NXT1), and a ubiquitin-associated domain that mediates the interaction with nucleoporins. Here we show that TAP belongs to an evolutionarily conserved family of proteins that has more than one member in higher eukaryotes. Not only the overall domain organization but also residues important for p15 and nucleoporin interaction are conserved in most family members. We characterize two of four human TAP homologues and show that one of them, NXF2, binds RNA, localizes to the nuclear envelope, and exhibits RNA export activity. NXF3, which does not bind RNA or localize to the nuclear rim, has no RNA export activity. Database searches revealed that although only one p15 (nxt) gene is present in the Drosophila melanogaster and Caenorhabditis elegans genomes, there is at least one additional p15 homologue (p15-2 [also called NXT2]) encoded by the human genome. Both human p15 homologues bind TAP, NXF2, and NXF3. Together, our results indicate that the TAP-p15 mRNA export pathway has diversified in higher eukaryotes compared to yeast, perhaps reflecting a greater substrate complexity.

High frequency of clonally related tumors in cases of multiple synchronous lung cancers as revealed by molecular diagnosis

In patients with multiple synchronous lung tumors, discrimination of multicentric lung cancers from intrapulmonary metastasis is important for treatment decision, but this is sometimes difficult. The aim of this study was to retrospectively distinguish multicentric lung cancers from intrapulmonary metastases in 14 such cases by loss of heterozygosity (LOH) and p53 mutational status. DNA was extracted from microdissected tumor cells in paraffin-embedded archival tissue, and 3p14.2, 3p21, 3p25, 9p21, and 18q21.1 were investigated for LOH. Exons 5-8 of the p53 gene were examined for mutations by the PCR, followed by single-strand conformation polymorphism analysis and DNA sequencing. For cases with the same LOH pattern, we calculated a clonality index, the probability of the given LOH pattern when these tumors were hypothesized to be independent in origin. Eleven of 14 cases (79%) were thus diagnosed as having pulmonary metastasis and only one case as having genuinely multicentric lung cancers. Two cases presented difficulty in diagnosis. In several cases, the LOH patterns conflicted with p53 mutation patterns, suggesting that clonal evolution is directly affected by certain genetic changes. The combination of p53 with LOH helped increase both the sensitivity and specificity of the assay.

Re-annotating the Mycoplasma pneumoniae genome sequence: adding value, function and reading frames

Four years after the original sequence submission, we have re-annotated the genome of Mycoplasma pneumoniae to incorporate novel data. The total number of ORFss has been increased from 677 to 688 (10 new proteins were predicted in intergenic regions, two further were newly identified by mass spectrometry and one protein ORF was dismissed) and the number of RNAs from 39 to 42 genes. For 19 of the now 35 tRNAs and for six other functional RNAs the exact genome positions were re-annotated and two new tRNA(Leu) and a small 200 nt RNA were identified. Sixteen protein reading frames were extended and eight shortened. For each ORF a consistent annotation vocabulary has been introduced. Annotation reasoning, annotation categories and comparisons to other published data on M.pneumoniae functional assignments are given. Experimental evidence includes 2-dimensional gel electrophoresis in combination with mass spectrometry as well as gene expression data from this study. Compared to the original annotation, we increased the number of proteins with predicted functional features from 349 to 458. The increase includes 36 new predictions and 73 protein assignments confirmed by the published literature. Furthermore, there are 23 reductions and 30 additions with respect to the previous annotation. mRNA expression data support transcription of 184 of the functionally unassigned reading frames.

Prediction of structural domains of TAP reveals details of its interaction with p15 and nucleoporins

Vertebrate TAP is a nuclear mRNA export factor homologous to yeast Mex67p. The middle domain of TAP binds directly to p15, a protein related to the nuclear transport factor 2 (NTF2), whereas its C-terminal domain interacts with various nucleoporins, the components of the nuclear pore complex (NPC). Here, we report that the middle domain of TAP is also similar to NTF2, as well as to regions in Ras-GAP SH3 domain binding protein (G3BP) and some plant protein kinases. Based on the known three-dimensional structure of NTF2 homodimer, a heterodimerization model of TAP and p15 could be inferred. This model was confirmed by site-directed mutagenesis of residues located at the dimer interface. Furthermore, the C-terminus of TAP was found to contain a ubiquitin-associated (UBA) domain. By site-directed mutagenesis we show that a conserved loop in this domain plays an essential role in mediating TAP-nucleoporin interaction.

HUGE: a database for human large proteins identified in the Kazusa cDNA sequencing project

HUGE is a database for human large proteins newly identified in the Kazusa cDNA project, the aim of which is to predict the primary structure of proteins from the sequences of human large cDNAs (>4 kb). In particular, cDNA clones capable of coding for large proteins (>50 kDa) are the current targets of the project. HUGE contains >1100 cDNA sequences and detailed information obtained through analysis of the sequences of cDNAs and the predicted proteins. Besides an increase in the number of cDNA entries, the amount of experimental data for expression profiling has been largely increased and data on chromosomal locations have been newly added. All of the protein-coding regions were examined by GeneMark analysis, and the results of a motif/domain search of each predicted protein sequence against the Pfam database have been newly added. HUGE is available through the WWW at http://www.kazusa.or.jp/huge

5-fluorouracil continuous infusion combined with cisplatin for advanced pancreatic cancer: a Japanese Cooperative Study

BACKGROUND/AIMS

The prognosis of patients with advanced pancreatic cancer is extremely poor. To improve their prognosis, providing effective chemotherapy is necessary. The aim of this study was to evaluate the anti-tumor activity and toxicity of combined chemotherapy (FP therapy) using 5-fluorouracil and cisplatin in Japanese chemo-naive patients with advanced pancreatic cancer.

METHODOLOGY

Thirty-seven previously untreated patients with histologically proven pancreatic adenocarcinoma were treated with FP therapy. 5-fluorouracil was administered at 500 mg/m2/day by continuous intravenous infusion for 5 days and cisplatin was administered at 80 mg/m2 intravenously on the 1st day. Therapy was repeated every 4 weeks until there was evidence of disease progression or unacceptable toxicity.

RESULTS

Three patients achieved partial responses, whereas none exhibited a complete response. The overall response rate was 8% (95% confidence interval, 2-22%) and the response durations were 6, 9 and 12 months, respectively. The median survival time of patients was 5 months. Toxicities were generally mild and acceptable, although nausea/vomiting was the most commonly observed toxicity.

CONCLUSIONS

FP therapy on this schedule had limited anti-tumor activity for pancreatic cancer, indicating that, practically, it should not be performed in Japanese patients with advanced pancreatic cancer.

Prediction of the coding sequences of unidentified human genes. XIII. The complete sequences of 100 new cDNA clones from brain which code for large proteins in vitro

As a part of our cDNA project for deducing the coding sequence of unidentified human genes, we newly determined the sequences of 100 cDNA clones from a set of size-fractionated human brain cDNA libraries, and predicted the coding sequences of the corresponding genes, named KIAA0919 to KIAA1018. The sequencing of these clones revealed that the average sizes of the inserts and corresponding open reading frames were 4.9 kb and 2.6 kb (882 amino acid residues), respectively. A computer search of the sequences against the public databases indicated that predicted coding sequences of 87 genes contained sequences similar to known genes, 53% of which (46 genes) were categorized as proteins relating to cell signaling/communication, cell structure/motility and nucleic acid management. The chromosomal locations of the genes were determined by using human-rodent hybrid panels unless their mapping data were already available in the public databases. The expression profiles of all the genes among 10 human tissues, 8 brain regions (amygdala, corpus callosum, cerebellum, caudate nucleus, hippocampus, substania nigra, subthalamic nucleus, and thalamus), spinal cord, fetal brain and fetal liver were also examined by reverse transcription-coupled polymerase chain reaction, products of which were quantified by enzyme-linked immunosorbent assay.

A method for comparing circular genomes from gene locations: application to mitochondrial genomes

MOTIVATION

Data on the entire structures of organelle and bacterial genomes, most of which are known to be circular, have accumulated at a rapid pace. This information enables us to utilize the locations of homologous gene pairs for measuring the dissimilarity between complete genomic structures.

RESULTS

A macroscopic distance is presented for comparing circular genomes from their overall structures, on the basis of the locations of two pairs of homologous genes on the compared genomes. The novel aspect of our method is that the comparison between the genomes automatically reveals a relationship based on the information on all gene locations, by incorporating the mobility of each gene, which includes not only the gene order, but also the relative location between gene pairs. The plausibility of the newly defined distances is evaluated by means of 44 mitochondrial genomes. The genome distance shows high performance for quantitatively describing the differences between the gene organizations of the genomes.

AVAILABILITY

Since the programs implementing these calculations require well-arranged gene organization data, they have not been released yet. However, one of the authors will analyze circular genomes upon request. Data on the gene organizations may be submitted electronically to the address below.

HUGE: a database for human large proteins identified by Kazusa cDNA sequencing project

HUGE is a database for human large proteins newly identified by Kazusa cDNA project, which aims to predict protein primary structures from sequences of human large cDNAs (>4 kb). In particular, cDNA clones capable of coding for large proteins (>50 kDa) are current targets of the project. More than 700 sequences of human cDNAs (average size, 5.1 kb) have been determined to date and deposited in the public databases. Notable information implied from the cDNAs and the predicted protein sequences can be obtained through HUGE via the World Wide Web at URL http://www.kazusa.or.jp/huge

Prediction of the coding sequences of unidentified human genes. XII. The complete sequences of 100 new cDNA clones from brain which code for large proteins in vitro

In this paper, we report the sequences of 100 cDNA clones newly determined from a set of size-fractionated human brain cDNA libraries and predict the coding sequences of the corresponding genes, named KIAA0819 to KIAA0918. These cDNA clones were selected on the basis of their coding potentials of large proteins (50 kDa and more) by using in vitro transcription/translation assays. The sequence data showed that the average sizes of the inserts and corresponding open reading frames are 4.4 kb and 2.5 kb (831 amino acid residues), respectively. Homology and motif/domain searches against the public databases indicated that the predicted coding sequences of 83 genes were similar to those of known genes, 59% of which (49 genes) were categorized as coding for proteins functionally related to cell signaling/communication, cell structure/motility and nucleic acid management. The chromosomal locations and the expression profiles of all the genes were also examined. For 54 clones including brain-specific ones, the mRNA levels were further examined among 8 brain regions (amygdala, corpus callosum, cerebellum, caudate nucleus, hippocampus, substantia nigra, subthalamic nucleus, and thalamus), spinal cord, and fetal brain.

[Clinical evaluation of MRCP]

Recently, MRCP can be obtained with good spacial resolution within a few seconds using half fourier fast spin echo technique. From July 1995 to August 1997, 1000 patients suspected of having pancreatobiliary diseases were examined with MRCP. MRCP was performed with 1.5 T scanner using Fast Asymmetric Spin Echo sequence (FASE). Satisfactory images of the main pancreatic duct were obtained in 98%, of Santorini's duct in 90%, and of uncinate process branch in 83%. Pancreas divism was accurately diagnosed. In the patients with pancreatic ductal adenocarcinomas, MRCP depicted stenosis and proximal dilatation of the main pancreatic duct in 89%, and in the remaining patients no abnormalities were seen in the main pancreatic ducts because tumors were limited to side branches or Santorini's duct or distal end of the tail of the pancreas. Diagnosis of small pancreatic carcinomas (smallest lesion measured 10 mm in diameter) were feasible. In the patients with intraductal papillary neoplasms, dilatation of the main pancreatic duct and cystic dilatation of side branches were depicted, and polypoid lesions were detectable with source images. In the patients with serous cystadenomas, accumulation of the microcysts were visualized. In the patients with chronic pancreatitis, dilatation and stenosis of the main pancreatic duct, as well as side branch dilatation was depicted despite overestimation of the extent of the stenosis. Stones in the main pancreatic duct were well visualized as intraductal filling defects. In conclusion, MRCP is an effective imaging technique in the diagnosis of various pancreatic diseases.

Prediction of the coding sequences of unidentified human genes. XI. The complete sequences of 100 new cDNA clones from brain which code for large proteins in vitro

In our series of projects for accumulating sequence information on the coding sequences of unidentified human genes, we have newly determined the sequences of 100 cDNA clones from a set of size-fractionated human brain cDNA libraries, and predicted the coding sequences of the corresponding genes, named KIAA0711 to KIAA0810. These cDNA clones were selected according to their coding potentials of large proteins (50 kDa and more) in vitro. The average sizes of the inserts and corresponding open reading frames were 4.3 kb and 2.6 kb (869 amino acid residues), respectively. Sequence analyses against the public databases indicated that the predicted coding sequences of 78 genes were similar to those of known genes, 64% of which (50 genes) were categorized as proteins functionally related to cell signaling/communication, cell structure/motility and nucleic acid management. As additional information concerning genes characterized in this study, the chromosomal locations of the clones were determined by using human-rodent hybrid panels and the expression profiles among 10 human tissues were examined by reverse transcription-coupled polymerase chain reaction which was substantially improved by enzyme-linked immunosorbent assay.

Clinical implications of p53 autoantibodies in the sera of patients with non-small-cell lung cancer

BACKGROUND

The presence of autoantibodies to p53 protein has been associated with the presence of p53 (also known as TP53) gene mutations in primary tumors and with poor prognosis. This study was undertaken to determine the clinical significance of p53 autoantibodies in patients with non-small-cell lung cancer (NSCLC).

METHODS

We studied 188 consecutive patients with NSCLC who underwent pulmonary resection and for whom preoperative serum was available. The presence of p53 autoantibodies, detected by use of two amino-terminal and two carboxy-terminal peptides (20-30 mers) as antigens and an enzyme-linked immunosorbent assay, was related to various clinicopathologic parameters and to overexpression of p53 protein in the primary tumor. For 22 patients who had p53 autoantibodies before surgery, we also examined sera taken during postoperative follow-up. Reported P values are two-sided.

RESULTS

Autoantibodies to p53 protein were detected in 38 patients. Patients with squamous cell carcinoma, those with more advanced disease (stage III-IV), and those with tumors that overexpressed p53 had a significantly higher incidence of p53 autoantibodies (P = .05,.0079, and .02, respectively). In all but one of the patients with postoperative serum samples, the antibody titer declined after surgery; however, there was no relationship between clinical course and this change in antibody titer. In addition, there was no relationship between the presence of p53 autoantibodies and overall survival in 171 patients who underwent potentially curative resection (P = .28); however, 13 patients with autoantibodies to amino-terminal peptides had a worse overall survival (P = .02).

CONCLUSIONS

In NSCLC, the incidence of p53 autoantibodies is associated with histologic type, stage, and p53 overexpression--but not with patient survival. Our data do not support the clinical utility of p53 autoantibodies as diagnostic or prognostic markers in patients with NSCLC.

Endoscopic ultrasound and intraductal ultrasound in the diagnosis of small pancreatic tumors

BACKGROUND

The purpose of this study was to assess the diagnostic value of endoscopic ultrasound (EUS) and intraductal ultrasound (IDUS) in the detection of small pancreatic tumors.

METHODS

EUS was performed in 166 patients with verified pancreatic disease. IDUS was performed in 46 patients. A microprobe was introduced into the main pancreatic duct through the papilla of Vater using the duodenoscope.

RESULTS

EUS was valuable in the detection of small pancreatic tumors. Ductal adenocarcinomas smaller than 1 cm were demonstrated as a hypoechoic mass with a central irregular hyperechoic area. EUS and IDUS were useful in the characterization of intraductal paillary tumors (ductectatic mucinous tumors). EUS demonstrated nodular excrescences, and IDUS depicted papillary proliferation of the duct epithelium, which are characteristic of carcinomas and adenomas but not of hyperplasia. Internal architecture of cystic neoplasms was clearly depicted by EUS, and differentiation of serous and mucinous tumors was readily achieved. A tumor as small as a 5-mm islet cell was demonstrated on EUS because islet cell tumors are very hypoechoic.

CONCLUSION

EUS and IDUS are relatively noninvasive procedures and are useful in the detection of small tumors and differentiation of pancreatic diseases.

Prediction of the coding sequences of unidentified human genes. X. The complete sequences of 100 new cDNA clones from brain which can code for large proteins in vitro

As an extension of our cDNA analysis for deducing the coding sequences of unidentified human genes, we have newly determined the sequences of 100 cDNA clones from a set of size-fractionated human brain cDNA libraries, and predicted the coding sequences of the corresponding genes, named KIAA0611 to KIAA0710. In vitro transcription-coupled translation assay was applied as the first screening to select cDNA clones which produce proteins with apparent molecular mass of 50 kDa and over. One hundred unidentified cDNA clones thus selected were then subjected to sequencing of entire inserts. The average size of the inserts and corresponding open reading frames was 4.9 kb and 2.8 kb (922 amino acid residues), respectively. Computer search of the sequences against the public databases indicated that predicted coding sequences of 87 genes were similar to those of known genes, 62% of which (54 genes) were categorized as proteins related to cell signaling/communication, cell structure/motility and nucleic acid management. The expression profiles in 10 human tissues of all the clones characterized in this study were examined by reverse transcription-coupled polymerase chain reaction and the chromosomal locations of the clones were determined by using human-rodent hybrid panels.

Imaging of small pancreatic ductal adenocarcinoma

Symptoms and laboratory studies provide only limited assistance in the diagnosis of small pancreatic carcinomas. Ultrasound and computed tomography are best suited for screening small pancreatic carcinomas because of their ease and accuracy. When findings of ultrasound and computed tomography suggest small pancreatic carcinomas, MR cholangiopancreatography and endoscopic ultrasound should be indicated. Both techniques can show very small tumors. Follow-up of 77 patients with pancreatic carcinoma in whom the tumor was resected showed a 100% 5-year survival rate of patients with tumor limited to the duct epithelium. The majority of these tumors were <1 cm. These tumors are considered early pancreatic carcinoma.

Establishment of human peripheral lung epithelial cell lines (HPL1) retaining differentiated characteristics and responsiveness to epidermal growth factor, hepatocyte growth factor, and transforming growth factor beta1

Novel human epithelial cell lines retaining characteristic features of normal peripheral airway cells were established by transfecting the SV40 large T antigen gene into primary in vitro outgrowths from normal peripheral lung specimens. These lines, designated as HPL1A to HPL1E, showed the polygonal shapes typical of epithelial cells and expressed cytokeratin in abundance. Ultrastructural examination revealed the presence of microvilli, multivesicular bodies, and multilamellar body-like structures that are characteristic of type II pneumocytes, but expression of CC1O transcripts, a highly specific marker for Clara cells, was also observed. Response to transforming growth factor beta, epidermal growth factor (EGF), and hepatocyte growth factor, all of which are thought to be important growth-regulatory molecules for cellular proliferation and developmental processes of peripheral lung, was apparent. In the HPL1A case, markedly altered cell morphology and cytoskeletal organization, potent inhibition of cell growth, and increased expression of an extracellular matrix protein were noted with transforming growth factor beta. Interestingly, both EGF and hepatocyte growth factor stimulated anchorage-dependent growth, whereas only EGF could sustain anchorage-independent proliferation. The HPL1 lines are, to our knowledge, the first series of stable epithelial lines of human peripheral lung to be described. They should be valuable for investigating various aspects of growth regulation and oncogenic processes, including the mechanisms of acquisition of anchorage independence and the interrelationships of genetic changes identified previously in lung cancers. In addition, the HPL1 lines may also prove useful for development of in vitro models for other human lung disorders as well as to elucidate the mechanisms of peripheral lung differentiation.

Mutations of the P53 tumor suppressor gene as clonal marker for multiple primary lung cancers

OBJECTIVES

Second primary lung cancers are prevalent after treatment for initial lung cancer, and the lung is also one of the most frequent sites for recurrence after removal of early-stage lung cancer. The objective of the present study is to clarify the clonal origin of the second tumor with the p53 gene mutation used as a clonal marker.

METHODS

Of 794 consecutive patients who underwent pulmonary resection for primary lung cancer from 1980 to 1993, 22 required second pulmonary resection during the follow-up period, with a median interval of 38 months. We examined 16 of these patients for mutations of the p53 gene occurring in exons 5 through 8 by the polymerase chain reaction/single strand conformation polymorphism method. Differential diagnosis was also made on a morphologic basis, considering the degree of cellular differentiation and cytologic subtypes.

RESULTS

Nine of the 16 patients analyzed had at least one p53 mutation in their tumors. We were thus able to make molecular diagnoses for these patients. The mutational status of the p53 gene was discordant in all nine patients, suggesting a different clonal origin despite the fact that six of them had almost identical histologic features.

CONCLUSIONS

Analysis of p53 gene mutations was thus useful in distinguishing second primary lung cancers from recurrent tumors. The observed heterogeneity of p53 status was also in line with the "field cancerization" concept.

[A carcinoma arising from benign pleomorphic adenoma of the trachea]

A 69-year-old female complained of husky voice and dyspnea. Bronchofiberscopic examination revealed a tumor at the left side of the trachea, which obstructed approximately 80% of the tracheal lumen. Benign pleomorphic adenoma was diagnosed by biopsy. The tumor was removed by circumferenctial resection of the trachea with partial sternotomy adding to the 3 th intercostal transverse resection. Historical finding of the resected specimen revealed a carcinoma arising from benign pleomorphic adenoma of the trachea and residue of malignancy at the margin of the trachea and esophagus. Additional radiotherapy was performed (60 Gy). The postoperative course was uneventful for 4 months and one year.

Prognostic significance of cyclin D1 and retinoblastoma expression in combination with p53 abnormalities in primary, resected non-small cell lung cancers

This study was conducted to evaluate the prognostic significance of cyclin D1 and retinoblastoma (Rb) expression in combination with abnormal p53 accumulation in primary, resected non-small cell lung cancers (NSCLCs). We evaluated immunohistochemically the expression of cyclin D1 and Rb in 208 NSCLC patients whose resections were consecutively performed between January 1984 and December 1988 and determined their prognostic significance by comparison with follow-up data. Expression of cyclin D1 and Rb was detected immunohistochemically in 39 and 80% of the 208 NSCLCs, respectively. The Kaplan-Meier survival curve demonstrated that absence of cyclin D1 expression was significantly associated with shortened survival (P = 0.01 by the log-rank test), particularly in adenocarcinomas (n = 100; P = 0.004). Expression status of the Rb protein was not significantly associated with clinical outcome in any of the cohorts. The predictive power of these prognosticators was also assessed in combination with findings for abnormal p53 accumulation by multivariate analysis using the Cox proportional hazards modeling. Patients with cyclin D1-negative tumors had a significantly greater risk of earlier death than those with cyclin D1-positive tumors (risk ratio, 1.61; P = 0.03), particularly in adenocarcinomas (risk ratio, 2.49; P = 0.002). Cases showing abnormal p53 accumulation tended to have a shortened survival only when the tumors were adenocarcinomas (risk ratio, 1.75; P = 0.06). Absence of cyclin D1 expression may be a useful prognosticator for shortened survival in primary, resected NSCLCs with particular significance for adenocarcinomas. In contrast, Rb expression status is not a useful prognostic factor for any type of NSCLC.

Comparison of protein structures using 3D profile alignment

A novel method for protein structure comparison using 3D profile alignment is presented. The 3D profile is a position-dependent scoring matrix derived from three-dimensional structures and is basically used to estimate sequence-structure compatibility for prediction of protein structure. Our idea is to compare two 3D profiles using a dynamic programming algorithm to obtain optimal alignment and a similarity score between them. When the 3D profile of hemoglobin was compared with each of the profiles in the library, which contained 325 profiles of representative structures, all the profiles of other globins were detected with relatively high scores, and proteins in the same structural class followed the globins. Exhaustive comparison of 3D profiles in the library was also performed to depict protein relatedness in the structure space. Using multidimensional scaling, a planar projection of points in the protein structure space revealed an overall grouping in terms of structural classes, i.e., all-alpha, all-beta, alpha/beta, and alpha+beta. These results differ in implication from those obtained by the conventional structure-structure comparison method. Differences are discussed with respect to the structural divergence of proteins in the course of molecular evolution.

Primary hepatic marginal zone B-cell lymphoma with mantle cell lymphoma phenotype

We report a rare case of primary hepatic lymphoma, Stage II disease, in a 48-year-old male who had a solitary hepatic tumour measuring 4 x 4.5 x 3 cm. The tumour showed a nodular growth pattern and lymphoepithelial lesions with bile ducts. Some neoplastic nodules had a non-neoplastic atrophic germinal centre and/or a thin mantle cell layer. Morphologically, the neoplastic cells were centrocyte-like cells or intermediate lymphocytes. They expressed L26(CD20)+/LN-1(CDw75)+/-/LN-2(CD74)+/cyclin D1- and had a monotypic immunoglobulin of cytoplasmic IgM (kappa) on paraffin sections. The neoplastic cells or neoplastic nodules expressed surface IgM+/surface IgD+/-/Leu-1(CD5)+/DRC-1+/alkaline phosphatase+/B1(CD20)+/B4(CD19)- on fresh frozen sections. We therefore diagnosed this case as primary hepatic marginal zone B-cell lymphoma with mantle cell lymphoma phenotype. We confirm that it is difficult to differentiate extranodal marginal zone B-cell lymphoma (low grade B-cell lymphoma of mucosa-associated lymphoid tissue type; MALT lymphoma) and mantle cell lymphoma.

Prognostic significance of abnormal p53 accumulation in primary, resected non-small-cell lung cancers

PURPOSE

This study was conducted to evaluate the prognostic significance of p53 abnormalities in primary, resected non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Methodologic validation of immunohistologic detection of p53 abnormalities in routine pathology sections was assessed using 31 lung cancer specimens for which p53 gene status was known from our previous molecular biologic studies. Applying the optimized cutoff value, we evaluated the prognostic significance of p53 abnormalities in an independent cohort of 208 NSCLC patients with complete follow-up data, whose resections were consecutively performed between January 1984 and December 1988.

RESULTS

Immunohistologic detection of p53 abnormalities appeared to be reliable and showed approximately 90% concordance with the p53 gene status. Using the selected cutoff value of 10%, 46% of 208 NSCLCs showed p53 abnormalities. There was no relationship between p53 abnormalities and clinical outcome in the entire cohort, which represented all histologic subtypes of NSCLC (P = .58). Based on the reasoning that the influence of p53 abnormalities may have been obscured by distinct biologic roles depending on histologic subtypes, we also separately analyzed subsets of patients with adenocarcinomas (n = 100) and with squamous cell carcinomas (n = 88) and found that it may be a useful prognosticator only in adenocarcinoma patients (P = .04).

CONCLUSION

p53 abnormalities are not a significant prognostic factor in primary, resected NSCLC when all histologic subtypes are combined, but may be a useful prognosticator for adenocarcinomas. Additional studies are warranted for further evaluation, specifically of adenocarcinomas.

Distinct mutational spectrum of the p53 gene in lung cancers from Chinese women in Hong Kong

Accumulating evidence suggests that the p53 gene is a good target for molecular epidemiological studies to search for risk factors in carcinogenic events. The lung cancer incidence for females in Hong Kong is unusually high, ranking among the highest in the world despite a low percentage with a history of smoking. To gain insights into possible etiological risk factors responsible for this high incidence, we examined p53 mutations in 35 lung cancer specimens from Chinese females living in Hong Kong and compared them with 35 matched cases from Japanese women as well as previously reported p53 mutations in the world literature. p53 mutations in exons 5-8 were present in 20 and 31% of the Hong Kong and Japanese cases, respectively. Notably, single-base deletions within runs of identical bases were observed in 3 (43%) of the 7 mutations in the Hong Kong cases, in contrast to the absence of such mutations in the controls and the extreme scarcity in the literature, suggesting that distinct environmental and/or genetic factor(s) might be involved. Although the frequent occurrence of characteristic single-base deletions could be a reflection of mutator mutations leading to inefficient mismatch repair of slipped strand mispairings, none of the lung cancer specimens exhibited such microsatellite instabilities.

Searching for common sequence patterns among distantly related proteins

We have developed a program Gap Allowing Pattern Explorer (GAPE) to extract amino acid sequence motifs conserved among distantly related proteins. The GAPE program is designed to allow gaps in the sequences. First, this program generates all possible amino acid patterns comprising up to five amino acids. Sequences containing the amino acid residues in the same order as a generated pattern are selected as subsequences, where the differences in the distances between two consecutive amino acids are ignored. Next, the motifs are extracted from the subsequences under conditions in which all four distances between the five amino acids are fixed. At this stage, motifs with gaps in their subsequence are also found by relaxing one of the four fixed distances. The statistical significance for a motif obtained is calculated based on the amino acid composition of the sequences under consideration. When the GAPE program was applied to 59 pyridoxal-phosphate-related sequences and 64 ATP (AMP-forming)-related sequences, motifs extracted with a low expectation of occurrence contained some of the amino acid residues chemically proved to be involved in the ligand recognition.

Expression of CD44 variant isoforms in normal and neoplastic cells of the lung

CD44 is a cell surface receptor that has been implicated in lymphocyte homing, hematopoiesis, cell migration and possibly also tumor metastasis. In the present study, expression of CD44 variant (CD44v) isoforms was analyzed in 23 lung cancer specimens together with corresponding normal lung tissues by Southern blot analysis coupled with reverse transcription-polymerase chain reaction amplification. We found that CD44v isoforms were expressed in all lung cancer specimens, suggesting a possible role in the establishment of metastases by these highly malignant tumors, but normal tissues were also positive. This is in marked contrast to the previous reports of essentially negligible expression of CD44v isoforms in normal colon and breast, and suggests a physiological function in the lung.

Synchronous lung cancer presenting with small cell carcinoma and adenocarcinoma

We describe a case of synchronous primary lung cancer presenting with small cell carcinoma and adenocarcinoma, in which expression of the cell surface antigens and also tumor markers were evaluated immunohistologically. A review of the literature concerning synchronous or metachronous primary lung cancers is also presented.

Searching for amino acid sequence motifs among enzymes: the Enzyme-Reaction Database

Recently we have constructed a database--the Enzyme-Reaction Database--which links a chemical structure to amino acid sequences of enzymes that recognize the chemical structure as their ligand. The total number of enzymes registered in the database is 1103 with 6668 NBRF-PIR entry codes and 1756 chemical compounds. The chemical structures and chemical names for 842 compounds are registered in the Chemical-Structure Database on the MACCS system. For each enzyme, the sequences were divided into clusters, and multiply aligned in each cluster to extract a conserved sequence. A total of 158,781 five-residue-long fragments were constructed from 433 conserved sequences and compared among different clusters of different enzymes. One of these motifs shared by different enzymes was S-G-G-L-D. The motif was conserved in both argininosuccinate synthase (EC 6.3.4.5) and asparagine synthase (glutamine-hydrolysing) (EC 6.3.5.4). This result showed that the database was useful for the analysis of the relationship between chemical structures and amino acid sequence motifs.

Prognostic significance of p53 mutations and 3p deletions in primary resected non-small cell lung cancer

We evaluated the prognostic significance of p53 mutations and an allelic loss of chromosome 3p in 71 patients with non-small cell lung cancer who underwent potentially curative resection. p53 mutations were detected in 35 cases (49%), while 3p deletions were observed in 34 of 70 informative cases (49%). The presence of the p53 mutation was associated with a shortened survival in all patients (P = 0.014 by log rank test), including those in early stages of the disease (stage I or II, n = 48) (P = 0.016 by log rank test). Multivariate analysis by the Cox proportional hazards model also revealed that p53 mutation was an independent yet unfavorable prognostic factor (P = 0.013). Patients with 3p deletion tended to have a poorer prognosis, but not to a statistically significant extent.