Loss of the Y chromosome is a frequent chromosomal imbalance in pancreatic cancer and allows differentiation to chronic pancreatitis.

In a study for the identification of genomic alterations in pancreatic cancer, representational difference analysis was used and led to the isolation of 2 distinct fragments, deleted on the Y chromosome in the xenografted tumor DNA of a male patient with an adenocarcinoma of the pancreas. Loss of Y chromosomal material was further studied in 11 pancreatic cancer cell lines of male origin, using PCR amplification of 5 sequence tagged sites (STSs) distributed along the Y chromosome; 8/11 cell lines exhibited a complete loss of the Y chromosome and 3 had deletions. To examine the status of the Y chromosome in situ, interphase FISH analysis was performed on paraffin sections from pancreatic carcinoma (n=7) and chronic pancreatitis (n=7) tissues, and the loss of Y-chromosomal STS-markers was studied in 6 xenograft tumors obtained from male pancreatic cancer patients. This analysis revealed that a loss of the Y chromosome occurs in vivo in primary pancreatic tumor cells, whereas the Y chromosome was intact in chronic pancreatitis. Our data suggest that loss of Y is a frequent event occurring in male pancreatic tumors. Although there is no evidence for a functional implication of Y chromosome loss, it effectively differentiates between a malignant and a benign condition as e.g. chronic pancreatitis. Thus, this genetic alteration may be of diagnostic use.

Tumour specific regulation of telomerase RNA gene expression visualized by in situ hybridization.

Maintenance of telomere structure by the ribonucleoprotein enzyme telomerase is considered central to the development of most human cancers. However, regulatory mechanisms governing telomerase expression during oncogenesis are largely unknown. We address potential tumour-specific regulation of telomerase RNA gene expression by RNA in situ hybridization to over 300 tumour samples of germ cell and epithelial origin. Twenty-six per cent of non-small cell lung cancers (NSCLC), expressed detectable levels of the telomerase RNA gene (hTR), and interestingly expression was almost confined to squamous carcinomas (41%), being rare in pulmonary adenocarcinomas and large-cell anaplastic carcinomas (P=0.006). Low frequency hTR expression was also associated with adenocarcinoma of the breast (13%), and ovary (17%). In comparison, hTR expression was detected in 43% of cervical cancers with no significant differences in frequency between squamous-cell carcinoma and adenocarcinoma or in transitions between intraepithelial neoplasia and invasive carcinoma. In contrast to the common epithelial cancers, the malignant cells in 73% of testicular germ-cell tumours (seminomas and teratomas), expressed hTR consistent with hTR expression in normal testicular germ cells. Differentiated tissues within ovarian germ cell tumours and in testicular teratomas lacked detectable hTR expression. These studies show that different tumour types have distinct patterns of hTR expression, which has implications for our understanding of mechanisms regulating telomerase activity and for targeting the telomerase RNA component as an anti-cancer therapy.

Amplification, increased dosage and in situ expression of the telomerase RNA gene in human cancer.

Telomere length is maintained by the enzyme, telomerase, which has been linked to cellular immortality and tumour progression. However, the reasons for the high levels of telomerase found in human tumours are unknown. We have mapped the human telomerase RNA gene, (hTR), to chromosome 3q26.3 and show the hTR gene to be amplified in four carcinomas, (2/33 cervix, 1/31 head and neck, 1/9 lung). In addition, increased copy numbers of the hTR locus was also observed in 97% of tumours. By in situ hybridisation, the histological distribution of high levels of hTR expression could be demonstrated in a lung tumour and its metastasis with hTR amplification. These results are the first report of genetic alterations involving a known component of telomerase in human cancer. Indeed, it is also the first report of the amplification of a specific locus within the chromosome 3q region frequently subject to copy number gains in human tumours. In addition, we also show for the first time the histological distribution of the RNA component of telomerase in human tumours.

Distinct nonrandom patterns of chromosomal aberrations in the progression of squamous cell carcinomas of the head and neck.

Fifty-one randomly selected primary squamous cell carcinomas of the head and neck, derived from the larynx (n = 18) and pharynx (oropharynx, n = 18, and hypopharynx, n = 15) were analyzed with centromeric probes for chromosomes 1, 7, 9, 11, 17, and 18 to study numerical aberrations, chromosome imbalances, and aneuploidy by fluorescence in situ hybridization. The tumors were grouped into nonmetastasizing (N0) tumors (from patients clinically free of lymph node metastases for at least 18 months after surgery, n = 25) and metastasizing (N1-3) tumors (n = 26). We found a significant association between the tumor ploidy and the nodal status; in the N0 group, diploidy prevailed, and the most common aberration was loss to monosomy for chromosome 9 (44%), whereas in the N1-3 group, aneuploidy predominated (P = 0.002). Specifically, these genomic changes associated with progression to metastasis were: (a) tetrasomic or polysomic chromosomes were detected in 17 of 26 N1-3 tumors but in none of the 25 N0 tumors (P < 0.0001); (b) heterogeneous chromosomal copy numbers (i.e., extensive chromosomal imbalances) were also much more frequent in the N1-3 tumors (69.2% versus 24.0% in the N0 group; P = 0.018); and (c) loss of chromosome 9 (73%) and gains of chromosomes 7 (35%) and 17 (31%) persisted, but in addition, loss of chromosome 18 occurred in 31%. Overexpression of the p53 protein correlated with an increased incidence of chromosomal imbalances and aneuploidy (P < 0.001) and, hence, constituted an additional risk factor. The lower metastatic potential of larynx tumors as compared with tumors from the pharynx was reflected by a lower incidence of these genomic changes. These specific patterns of chromosomal aberrations can characterize and distinguish different stages of tumor progression of squamous cell carcinomas of the head and neck and should be valuable diagnostic and prognostic markers.

[Abnormalities of the upper gastrointestinal tract diagnosed prenatally by ultrasound]. / Pränatal mittels Ultraschall diagnostizierte Missbildungen des oberen Gastrointestinaltraktes.

A hydramnion occurring during the second half of pregnancy may be due to atresias in the upper intestinal tract. Generally, one case of oesophageal atresia is likely to occur in every 2,500 births, often together with other malformations. Prenatal diagnosis of such atresias substantially improves prognosis for these children via optimal cooperation between the obstetrician and the paediatric surgeon. Characteristic features of oesophageal atresia in the sonographic image are, besides the hydramnion, the absence of visualisation of the stomach. Sonographic diagnosis of duodenal atresias is based on visualisation of the stomach, which is excessively filled with fluid, and of the portion of the small intestine located cranially of the stenosis. The patients treated by the author and presented here were successfully operated on via termination of birth and immediate surgery by the paediatric surgeon.

Synthesis and pharmacological activity of befuraline (N-benzo[b]furan-2-ylcarbonyl-N'-benzylpiperazine), a new antidepressant compound.

The methods of synthesis and the pharmacological evaluation of a new non-tricyclic antidepressant drug, N-benzo[b]furan-2-ylcarbonyl-N'-benzylpiperazine (befuraline), are reported. The chemical structure of befuraline is clearly different from that of the tricyclic antidepressant drugs. While the gross behavior in animals remains unaffected, the central nervous system depressed by reserpine, tetrabenazine or perphenazine is activated by even small doses of this novel compound. Exploratory activity is prolonged, and performance in operant behavior tests and in the conditioned avoidance response is improved by befuraline, indicating increased alertness, attentiveness and the capacity to react to environmental stimuli. High doses stimulate the CNS, causing EEG desynchronization. Befuraline displays an aggression-inhibiting activity; without having a sedative effect on the animals' normal behavior, it inhibits fighting behavior. The central anticholinergic effect of befuraline is negligible. No apomorphine or tryptamine potentiation is observed and hexobarbital anesthesia is not influenced. The peripheral autonomic nervous system, with the exception of the nictitating membrane in cats, is not affected by befuraline. It has a biphasic effect on the norepinephrine induced contraction of isolated guinea pig seminal vesicle and of isolated cat spleen slices. Although the mechanism of action is as yet not clear, it is assumed that, in addition to a direct influence on the central adrenergic structures, the inhibition of norepinephrine and serotonin uptake and the inhibition of phosphodiesterase are responsible for the drug's effect. Befuraline has no undesirable effects on either the peripheral autonomic nervous system or the cardiovascular system, and it does not affect the normal gross behavior of animals. Because these favorable therapeutic aspects are coupled with low toxicity, befuraline may provide a new alternative in the treatment of depression.