Recombinations of chromosomal bands 6p21 and 14q24 characterise pulmonary hamartomas

Cytogenetic analysis of short-term cultures from seven pulmonary hamartomas revealed an abnormal karyotype in six of them. The most characteristic aberration was an exchange of material between 6p21 and 14q24, found in three tumours. Abnormalities of either 6p or 14q were seen in another two hamartomas. Other regions that were rearranged more than once were 12q (three times) and 17p (twice), sometimes in exchange with 6p or 14q and giving rise to complex derivative chromosomes. Only one tumour had aberrations that did not involve 6p, 12q, 14q, or 17p. These results-together with the data on three previously reported pulmonary hamartomas, two of which also had t(6;14)-show that recombinations between 6p21 and 14q24 are common, and hence probably pathogenetically important. The data support the view that these tumours are genuine neoplasms rather than developmental anomalies. The coexistence of a common 14q24 breakpoint in uterine leiomyomas and pulmonary hamartomas indicates that a gene important in the genesis of both tumours exists in this band.     

Loss of heterozygosity and mutation analysis of the p16 (9p21) and p53 (17p13) genes in squamous cell carcinoma of the head and neck

We analyzed allelic loss at the p53 gene (17p13) and at chromosome region 9p21 in 35 primary head and neck squamous cell carcinomas. Loss of heterozygosity (LOH) at p53 and 9p21 was found in 50 and 75% of informative cases, respectively. LOH at the p53 gene did not increase significantly with tumor stage, but was more frequent in moderately and poorly differentiated tumors than in well-differentiated tumors. LOH plus mutation or homozygous deletion of p53 was limited to advanced stage and poorly differentiated tumors. Allelic loss at 9p21 is frequent in early stage head and neck squamous cell carcinoma and is not significantly associated with LOH at p53. The second exon of the p16/MTS1/CDKN2 gene was found to be homozygously deleted in 1 of 19 cases showing LOH at 9p21, but direct sequencing did not show mutations in the remaining 18 cases. This suggests that p16 plays a limited role in the development of head and neck squamous cell carcinoma.     

Recurrent DNA copy number changes in 1q, 4q, 6q, 9p, 13q, 14q and 22q detected by comparative genomic hybridization in malignant mesothelioma

Comparative genomic hybridization (CGH) analyses were performed on 27 human pleural mesothelioma tumour specimens, consisting of 18 frozen tumours and nine paraffin-embedded tumours, to screen for gains and losses of DNA sequences. Copy number changes were detected in 15 of the 27 specimens with a range from one to eight per specimen. On average, more losses than gains of genetic material were observed. The loss of DNA sequences occurred most commonly in the short arm of chromosome 9 (p21-pter), in 60% of the abnormal specimens. Other losses among the abnormal specimens were frequently detected in the long arms of chromosomes 4 (q31.1-qter, 20%), 6 (q22-q24, 33%), 13 (33%),14 (q24-qter, 33%) and 22 (q13, 20%). A gain in DNA sequences was found in the long arm of chromosome 1 (cen-qter) in 33% of the abnormal specimens. Our analysis is the first genome-wide screening for gains and losses of DNA sequences using comparative genomic hybridization in malignant pleural mesothelioma tumours. The recurrent DNA sequence changes detected in this study suggest that the corresponding chromosomal areas most probably contain genes important for the initiation and progression of mesothelioma.     

Impact of chromosome 14q loss on survival in primary head and neck squamous cell carcinoma

OBJECTIVE: To investigate somesthetic functions of the perisylvian cortex. METHODS: Somatosensory evoked magnetic fields (SEFs) and somatosensory evoked potentials (SEPs) of the perisylvian cortex were recorded directly from subdural electrodes in a patient with a left frontal brain tumour. RESULTS: The most prominent SEP components after electrical stimulation of the right and left hands and the right foot were double peaked negativity recorded just above the sylvian fissure (latency 80 to 150 ms), respectively (N1a and N1b). Generator sources for the magnetoencephalographic counterparts of those peaks (N1a(m) and N1b(m)) were both localised at the upper bank of the sylvian fissure, and those of N1a(m) were more anteromedially located than those of N1b(m). CONCLUSIONS: These findings suggest the existence of at least two separate somatosensory areas within the human perisylvian cortex.     

Prognostic significance of p53 gene mutations in squamous cell carcinoma of the lung

The aim of the present study was to analyze the prevalence and clinical importance of p53 gene mutations in surgically treated squamous cell lung carcinoma. Sixty patients were included. Fifty-one patients in stages I to IIIa were submitted to radical resection. Twenty-five samples tested positive for the p53 immunohistochemistry assay, and were analyzed for p53 gene mutations. Eleven mutations were found. Patients harboring p53 gene mutations suffered a higher incidence of recurrence and a higher mortality rate. Disease-free interval and overall survival were shorter for patients with mutated p53 gene (p=0.03 and p=0.005, respectively).     

Sequential molecular abnormalities are involved in the multistage development of squamous cell lung carcinoma

To understand the molecular pathways involved in the pathogenesis of squamous cell lung carcinoma, we obtained DNA from 94 microdissected foci from 12 archival surgically resected tumors including histologically normal epithelium (n=13), preneoplastic lesions (n=54), carcinoma is situ (CIS) (n=15) and invasive tumors (n=12). We determined loss of heterozygosity (LOH) at 10 chromosomal regions (3p12, 3p14.2, 3p14.1-21.3, 3p21, 3p22-24, 3p25, 5q22, 9p21, 13q14 RB, and 17p13 TP53) frequently deleted in lung cancer, using 31 polymorphic microsatellite markers, including 24 that spanned the entire 3p arm. Our major findings are as follows: (1) Thirty one percent of histologically normal epithelium and 42% of mildly abnormal (hyperplasia/metaplasia) specimens had clones of cells with allelic loss at one or more regions; (2) There was a progressive increase of the overall LOH frequency within clones with increasing severity of histopathological changes; (3) The earliest and most frequent regions of allelic loss occurred at 3p21, 3p22-24, 3p25 and 9p21; (4) The size of the 3p deletions increased with progressive histologic changes; (5) TP53 allelic loss was present in many histologically advanced lesions (dysplasia and CIS); (6) Analyses of 58 normal and non-invasive foci having any molecular abnormality, indicated that 30 probably arose as independent clonal events, while 28 were potentially of the same clonal origin as the corresponding tumor; (7) Nevertheless, when the allelic losses in the 30 clonally independent lesions and their clonally unrelated tumors were compared the same parental allele was lost in 113 of 125 (90%) of comparisons. The mechanism by which this phenomenon (known as allele specific mutations) occurs is unknown; (8) Four patterns of allelic loss in clones were found. Histologically normal or mildly abnormal foci had a negative pattern (no allelic loss) or early pattern of loss while all foci of CIS and invasive tumor had an advanced pattern. However dysplasias demonstrated the entire spectrum of allelic loss patterns, and were the only histologic category having the intermediate pattern. Our findings indicate that multiple, sequentially occurring allele specific molecular changes commence in widely dispersed, apparently clonally independent foci, early in the multistage pathogenesis of squamous cell carcinomas of the lung.     

Chromosome 3p loss of heterozygosity and mutation analysis of the FHIT and beta-cat genes in squamous cell carcinoma of the head and neck

BACKGROUND: Patients treated with clozapine have been reported to gain weight. We hypothesized that patients would also experience an increase in body mass, which can be more directly related to cardiovascular morbidity. METHODS: Forty-two patients who had been treated with clozapine for at least 1 year were weighed and measured, and waist-hip ratios (WHR) and body mass index (BMI), measured as kg/m2, were calculated. Patients were also asked about a series of factors potentially related to change in body mass. RESULTS: Female patients gained both weight and body mass. Their WHR after 37 months of clozapine therapy was .83, with a significant increase in BMI from 23.2 to 29.1 kg/m2 (p = .001). Male subjects also gained weight and body mass. Their WHR after 39 months of clozapine therapy was .93, with a significant increase in BMI from 26.4 to 29.7 kg/m2 (p < .001). Stepwise multiple-regression analysis showed that factors related to final body mass were initial body mass, dose of clozapine, and decrease in smoking. Baseline BMI contributed most to the final BMI, but the addition of dose and decrease in smoking made significant contributions to the model. CONCLUSIONS: Both female and male patients treated with clozapine gain body mass. This may place them at greater risk for cardiovascular morbidity.     

A case of primary splenic large cell lymphoma with a t(9;14)(p13;q32)

Appropriately substituted 2,3-dihydro-7H-thiazolo[3,2-a]pyrimidin-7-ones 9-12 and 18 were considered as annulated analogues of HEPT (1-[(2-hydroxyethoxy)methyl]-6-(phenylthio)-thymine), and some of these compounds were also found active against HIV-1, the most active one being 2,3-dihydro-5-[(3,5-dimethylphenyl)methyl]-3-ethoxy-6-ethyl-7H- thiazolo[3,2-a]pyrimidin-7-one (10b). S-Alkylation of 5-alkyl-6-(arylmethyl)-2-thiouracils 1-4 was performed with 2-bromoacetaldehyde acetals to furnish the S-[bis(alkoxy)ethyl] derivatives 5-8 and with allyl bromide to furnish S-allyl derivatives 17. The target compounds 9-12 were obtained by an N1 regioselective intramolecular cyclization reaction of silylated 5-8 using trimethylsilyl trifluoromethanesulfonate (TMS triflate) as the catalyst. Treatment of the S-allyl derivatives 17 with bromine in dry methylene chloride afforded the 3-(bromomethyl) derivatives 18.     

Two acute monocytic leukemia (AML-M5a) cell lines (MOLM-13 and MOLM-14) with interclonal phenotypic heterogeneity showing MLL-AF9 fusion resulting from an occult chromosome insertion, ins(11;9)(q23;p22p23)

We describe two new human leukemia cell lines, MOLM-13 and MOLM-14, established from the peripheral blood of a patient at relapse of acute monocytic leukemia, FAB M5a, which had evolved from myelodysplastic syndrome (MDS). Both cell lines express monocyte-specific esterase (MSE) and MLL-AF9 fusion mRNA. Gene fusion is associated with a minute chromosomal insertion, ins(11;9)(q23;p22p23). MOLM-13 and MOLM-14 are the first cell lines with, and represent the third reported case of, MLL gene rearrangement arising via chromosomal insertion. Both cell lines carry trisomy 8 which was also present during the MDS phase, as well as the most frequent trisomies associated with t(9;11), ie, +6, +13, +19 variously present in different subclones. Despite having these features in common, differences in antigen expression were noted between the two cell lines: that of MOLM-13 being CD34+, CD13-, CD14-, CD15+, CD33+; whereas MOLM-14 was CD4+, CD13+, CD14+, CD15+, CD33+. Differentiation to macrophage-like morphology could be induced in both cell lines after stimulation with INF-gamma alone, or in combination with TNF-alpha, which treatment also induced or upregulated, expression of certain myelomonocyte-associated antigens, including CD13, CD14, CD15, CD64, CD65 and CD87. Together, these data confirm that both cell lines are likely to be novel in vitro models for studying monocytic differentiation and leukemogenesis.     

bcl-2, p53 immunophenotypes and apoptosis in squamous cell carcinoma of the oesophagus

To establish baseline information on neopterin concentrations in livestock, companion and laboratory animals and identify the factors that may influence these concentrations, blood samples were taken from normal dairy cattle, horses, llamas, dogs, cats and rats of varying ages and sexes. In addition, neopterin concentrations in normal, adult equines were compared with those found in racing Thoroughbreds. There were no differences due to sex, sexual maturity, pregnancy, castration, or age. For all ages and sexes combined, mean neopterin concentrations were significantly lower in llamas (2.27+/-0.33 nmol litre(-1)) and rats (2.13+/-0.21 nmol litre(-1)) when compared with the other species tested. Racing Thoroughbreds demonstrated higher neopterin values than adult equines not in training (3.54+/-0.64 vs 3.13+/-1.02 nmol litre(-1)).     

Homozygous deletions at chromosome 9p21 and mutation analysis of p16 and p15 in microdissected primary non-small cell lung cancers

Loss of heterozygosity on chromosome 9p has been detected in many primary human tumors and cell lines, suggesting that this chromosomal arm harbors one or more tumor suppressor genes. The recently cloned p16 and p15 genes, mapped to 9p21, are likely candidates for such tumor suppressors. To map the deletion at chromosome 9p21 in non-small cell lung tumors, we analyzed DNA from 25 tumors and matching normal DNAs at six microsatellite markers that flank the region occupied by the p16 and p15 genes. Loss of heterozygosity of at least one microsatellite marker on chromosome 9p21 was detected in 13 (52%) of 25 tumors, including one tumor that exhibited homozygous deletion of both human IFNalpha and D9S171. Six tumors analyzed by a comparative multiplex PCR technique showed homozygous deletions of the sequence tag site marker c5.1 (within p16). Screening for mutations in p16 and p15 revealed one tumor with a non-sense mutation in exon 2 of p16, but no mutations were detected in p15 in any of the tumors. Thus, in these analyses approximately one-half of the non-small cell lung tumors had loss of heterozygosity at chromosome 9p21, and of these tumors, one-half had homozygous deletions of the region that includes p16. This appears to confirm the importance of a locus in this region critical to growth control in lung. The apparent lack of other mutations in p16 and p15 in the tumors with loss of heterozygosity leaves open the possibility of an unidentified gene in this region that may function as a tumor suppressor.     

Alterations of p53 gene and Ha-ras gene are independent events in solar keratosis and squamous cell carcinoma

In order to clarity the multiple-step progression from solar keratosis to squamous cell carcinoma, aberrations of the p53 gene (exons 2-11) and ras genes (exons 1 and 2) in solar keratosis and squamous cell carcinoma were investigated by polymerase chain reaction and single-strand conformation polymorphism analysis. In a series of Japanese patients, eight of 27 (30%) samples of solar keratosis and three of six (50%) samples of squamous cell carcinoma showed structural abnormalities in the p53 gene. Only one solar keratosis (4%) showed a point mutation in the Ha-ras gene but not in the p53 gene. Among these cases, no mutation of ras genes could be detected in squamous cell carcinoma. Simultaneous mutation of ras genes and the p53 gene was not detected in any cases of either solar keratosis or squamous cell carcinoma. It is concluded that aberrations of the p53 gene and ras genes are induced through independent processes of ultraviolet irradiation in the course of carcinogenic change from solar keratosis to squamous cell carcinoma.     

Carcinoma of the lung in Okinawa, Japan: with special reference to squamous cell carcinoma and squamous metaplasia

In Okinawa, a subtropical island in southern Japan, squamous cell carcinoma (SCC), especially the well-differentiated form, is prevalent, while this form is relatively rare in both the mainland and other countries (e.g. United States of America). More patients with SCC from Okinawa, moreover, were positive for human papillomavirus (HPV) DNA by polymerase chain reaction (PCR) (79%), and harbored HPV types 6, 16 and 18, in combination. On the other hand, less than 30% of the mainland patients were positive for HPV DNA by PCR. Those patients who were positive all harbored only one HPV type. Furthermore, in Okinawa, there were a significant number of cases with adenosquamous carcinoma, and they too were positive for HPV DNA. The SCC and the adenocarcinoma cells adjacent to the SCC component in these cases were also positive for HPV DNA, and such adenocarcinoma cells were enlarged in size with relatively wide cytoplasm. The authors postulate that HPV infects adenocarcinoma cells and changes them to enlarged cells, followed by squamous metaplasia. In this report, HPV DNA was transfected to adenocarcinoma cells (cultured cell lines) and this showed that HPV causes squamous metaplasia. In addition, aberrant expression of p53 was demonstrated in a large number of the SCC cases in Okinawa. The enlarged adenocarcinoma cells adjacent to the SCC components in adenosquamous carcinomas also showed aberrant expression of p53. The recent advances in the studies of anti-oncogenes, p53, etc. and oncogenes are outlined. It is to be noted that the molecular mechanisms of carcinogenesis in the lung have been studied in general, classifying lung tumors into two groups, namely, small cell carcinoma (SCLC) and non-small cell carcinoma (NSCLC). However, because human lung cancer is represented by a wide variety of histologic types, molecular genetic studies according to a more detailed histological subclassification is needed.     

Expression of p53 and p21 proteins in oral squamous cell carcinoma: correlation with lymph node metastasis and response to chemoradiotherapy

p53 protein, a product of the p53 cancer suppressor gene, and p21 protein, a cyclin-dependent kinase inhibitor, were immunohistochemically investigated in 150 oral squamous cell carcinomas (SCCs) and the relationship between their expression and clinicopathological findings were evaluated. The positivity for p53 and p21 proteins was not correlated with the T-stage, mode of tumor cell invasion or tumor cell differentiation. However, the expression of p53 and p21 proteins was correlated with lymph node metastasis. Of 62 SCCs with regional lymph node metastasis, 45 SCCs (72.6%) were positive for p53 while 45 (52.9%) of 88 SCCs without metastasis expressed p53 protein (p < 0.02). In addition, p21 protein was observed in 25 (38.5%) and 18 (21.2%) SCCs with and without metastasis, respectively (p < 0.05). Furthermore, p53 protein was inversely correlated with the histopathological effect of inductive chemoradiotherapy; the rate of chemoradiotherapy-induced lethal degeneration (56.7%) in p53-negative SCCs was significantly higher than that (28.9%) in p53-positive SCCs (p < 0.005). However, no clear difference in the effect was observed between p21-positive and p21-negative SCCs. Finally, the 5-year-survival rate was highest in p53(-)-p21(+) (80.0%) followed by 76.3% in p53(-)-p21(-), 65.9% in p53(+)-p21(+) and 65.4% in p53(+)-21p(-) SCCs. These results indicate that although the expression of p21 protein is only weakly correlated with the clinico-histopathological findings, p53 protein is a useful prognostic marker and that inductive chemoradiotherapy can be successfully planned by immunohistochemical examination of p53 protein.     

Fluorescence in situ mapping of the human nuclear NAD+ ADP-ribosyltransferase gene (ADPRT) and two secondary sites to human chromosomal bands 1q42, 13q34, and 14q24

A 3.5-kb cDNA probe containing the 23 exons from the coding sequence of human nuclear NAD+ ADP-ribosyltransferase (poly [ADP-ribose] polymerase [ADPRT], E.C.2.4.2.30) was used to map the gene and two additional sites by nonisotopic in situ chromosomal hybridization. The previous localization of the structural gene on 1q42 was confirmed. Two other hybridization peaks on 13q34 and 14q24 suggested the presence of ADPRT pseudogenes.     

High incidence of translocations t(11;14)(q13;q32) and t(4;14)(p16;q32) in patients with plasma cell malignancies

Abnormalities involving the 14q32 region are recurrent chromosomal changes in plasma cell malignancies. Recent preliminary molecular analyses found IGH rearrangements in almost 100% of human myeloma cell lines and in 75% of patients. However, no systematic study analyzing the nature of the partner chromosomal regions have been reported thus far. To define the exact incidence of illegitimate IGH rearrangements and the respective incidence of partner genes cloned to date, we analyzed 141 patients with either multiple myeloma (MM, n = 127) or primary plasma cell leukemia (PCL, n = 14) using fluorescence in situ hybridization. The overall incidence of illegitimate recombinations was 57% (80 of 141 patients). Analysis of this incidence according to Durie and Salmon stage, patients' status, i.e., MM versus primary PCL and diagnosis versus relapse, immunoglobulin type and subtype, and beta2-microglobulin value, did not show any correlation. To analyze the nature of the partner chromosomal region, we selected probes specific for the following genes: FGFR3 (4p16), MYC (8q24), CCND1 (11q13), MAF (16q23), and BCL2 (18q21). These probes, combined with differentially labeled 14q32 probes, were used for dual-color fluorescence in situ hybridization on interphase plasma cells. Among the 80 patients with illegitimate IGH rearrangement, we identified 23 IGH-CCND1 fusion cases [i.e., t(11;14)], 17 IGH-FGFR3 fusion cases [i.e., t(4;14)], 3 IGH-MYC fusion cases [i.e., t(8;14)], and only one IGH-MAF fusion case. No IGH-BCL2 fusion case was detected. In 37 of 80 patients, none of these partner genes was involved. Analysis of cases with specific translocations according to their bioclinical features at diagnosis did not show any correlation. This study demonstrated that CCND1 and FGFR3 genes are involved together in about 50% of MM and primary PCL patients with illegitimate IGH rearrangements.     

Allelic loss at chromosomes 3p, 8p, 13q, and 17p associated with poor prognosis in head and neck cancer

BACKGROUND: Little is known about the molecular genetic events that contribute to the pathogenesis of squamous cell carcinoma of the upper aerodigestive tract. Previous molecular genetic studies have been limited to the identification of mutations of the p53 (also known as TP53) tumor suppressor gene, activation of a limited set of oncogenes, allelic loss at 3p and other locations, and occasional association with human papillomavirus infection. PURPOSE: Our purpose was to screen tumor tissue and blood from patients with squamous cell carcinoma of the upper aerodigestive tract for loss of heterozygosity at polymorphic loci corresponding to each of the autosomal chromosomes and to identify the locations of additional putative tumor suppressor genes, other than RB (also known as RB1) and p53, that may contribute to the pathogenesis of this disease. METHODS: Tumor tissue and blood were obtained from 68 consecutive patients with squamous cell carcinoma of the upper aerodigestive tract. In all cases, tumor tissue was obtained from the center of the surgical specimen. The relative absence of non-neoplastic tissue was confirmed by frozen-section histologic examination of immediately adjacent tissue. Initially, 30 paired tissue and blood samples were tested for loss of heterozygosity by polymerase chain reaction (PCR) to amplify 43 different highly polymorphic sequences containing small oligonucleotide repeats. After PCR amplification, with unique oligonucleotides flanking the repeat, visualization and sizing of the alleles on DNA sequencing gels were performed. Specific loss of heterozygosity was distinguished from random genetic loss due to generalized chromosomal instability if it occurred in more than 20% of specimens tested for a particular marker. RESULTS: Significant loss of heterozygosity (> 20%) occurred at alleles at chromosome bands 3p21 (32%), 3p25-26 (56%), 8pter-21.1 (31%), 13q14 (27%), and 17p12 (45%). Loss of heterozygosity at more than two loci was significant with a poor prognosis (P = .039). CONCLUSIONS: These findings demonstrate that squamous cell carcinoma of the upper aerodigestive tract exhibits genetic alterations at multiple loci and that allelic loss at more than two locations is indicative of a poor prognosis (the likelihood of the patient dying of disease). IMPLICATIONS: While tumor suppressor genes at 3p (VHL), 13q (RB), and 17p (p53) have been identified, altered genes at other loci on 3p and on 8p have not yet been characterized. Furthermore, the genotype at these loci for squamous cell carcinoma of the upper aerodigestive tract has prognostic importance and may identify the patients who should receive the most aggressive treatment.