Case-control study of congenital anomalies in children of cancer patients

OBJECTIVES

To determine whether the offspring of cancer survivors are at an increased risk of congenital anomalies and whether cancer therapy before conception is associated with such an increase.

DESIGN

Case-control study using computerised record linkage.

SETTING

Ontario, Canada.

SUBJECTS

Parents of children born during April 1979 to December 1986 who had a congenital anomaly diagnosed within the first year of life (45,200 mothers and 41,158 fathers) and a matched sample of parents whose children did not have a congenital anomaly (45,200 mothers and 41,158 fathers).

MAIN OUTCOME MEASURES

Cancer diagnosed in either parent before conception and radiotherapy to the pelvis or abdomen or chemotherapy with an alkylating agent.

RESULTS

Among the mothers, 54 cases and 52 controls were identified as having had cancer diagnosed in Ontario (relative risk = 1.04, 95% confidence interval 0.7 to 1.5) and among the fathers, 61 cases and 65 controls were identified (0.9, 0.7 to 1.4). No significant associations were found between congenital anomalies in the offspring and any type of cancer treatment in either the mothers or the fathers.

CONCLUSIONS

The risk of congenital anomalies among liveborn offspring whose parents have had cancer or been treated for cancer is not higher than that in the general population.

Conserved sequence and functional domains in satellite 2 from three families of salamanders

Thirteen satellite 2 elements from Ambystoma talpoideum and 16 from Amphiuma tridactylum were cloned, sequenced, and compared with the satellite 2 consensus from Notophthalmus viridescens. These elements have maintained a high degree of similarity during the 65-200 Myr that the salamander families, represented by the three species, have been separated. The DNA sequences of the consensus elements from A. talpoideum and A. tridactylum are 81% similar, and both are approximately 65% similar to the N. viridescens consensus. In addition to its DNA sequence, the functional properties of satellite 2 have also been conserved. By selecting and analyzing clones that closely mimicked the consensus of each species, we were able to demonstrate that satellite 2 from each species was capable of promoting transcription after injection into Xenopus laevis oocytes and that synthetic transcripts of satellite 2 from each species were capable of catalyzing their own site-specific cleavage. These properties may be related to the process of retroposition, which was previously proposed to be responsible for the genomic proliferation of satellite 2. Each of these functional properties also has general biological interest.

The role of the cell-cell adhesion molecule E-cadherin in large bowel tumour cell invasion and metastasis

It has been suggested that the selective loss of E-cadherin expression can generate invasiveness in human carcinoma cells and might be a predictor of metastasis. Frozen sections of samples from 44 patients, 43 with suspected large bowel cancer and one with a liver recurrence were examined for E-cadherin expression using the antibody 6F9 specific for the human E-cadherin molecule. Twelve of the 40 patients with carcinoma already had lymph node involvement at the time of surgery. Samples from the primary carcinomas of only nine of these 12 patients showed reduced E-cadherin expression. However, the one lymph node with metastatic spread examined did show reduced E-cadherin expression. Four of the 40 carcinoma patients had liver involvement at the time of surgery. The primary carcinoma samples from only three of these four patients showed reduced E-cadherin expression. In addition only two out of the three liver metastases examined showed reduced expression. The primary carcinoma samples from seven patients with no evidence of tumour spread also exhibited reduced expression. Overall, analysis of the data suggests that there is no absolute correlation between reduced E-cadherin expression and tumour spread in carcinomas of the large bowel.

Immunocytochemical identification of cell types in benign and malignant breast diseases: variations in cell markers accompany the malignant state

We performed immunocytochemical staining of benign, in situ, and malignant breast disease to identify antigens related to the presence of the major parenchymal cell types of the normal breast. Markers for the epithelial cells, antiserum to epithelial membrane antigen, and three monoclonal antibodies (MAb) to milk-fat globule membranes stained most of the inner cells in benign breast lesions, carcinoma in situ, and invasive carcinomas, but the peripheral cells in benign lesions, as well as in carcinoma in situ, were unstained. MAb to epithelium-specific keratin 18 stained the majority of inner cells in benign breast lesions but comparatively fewer such cells in carcinoma in situ and invasive carcinoma. Markers for the myoepithelial cells, antisera, and MAb to smooth muscle actin and vimentin stained most of the peripheral cells in benign breast lesions and in carcinoma in situ but failed to stain virtually any neoplastic cells in invasive carcinomas. Markers for the basement membrane adjacent to the myoepithelial cells, antiserum, and MAb to laminin and Type IV collagen delineated an intact basement membrane around benign lesions and carcinoma in situ, and fragmented structures in 5-10% of invasive carcinomas; the remaining carcinomas were largely unstained. Markers for both myoepithelial and epithelial cells, keratin MAb PKK2 and LP34, stained most of the inner cells in benign lesions but usually only relatively few malignant cells in carcinoma in situ and invasive carcinomas. Markers for the secretory alveolar cell, MAb to beta- and kappa-casein, stained a few isolated cells in benign lesions, many more inner cells in two such lesions in pregnant females, and none in invasive carcinomas. In conclusion, the myoepithelial cell and, under suitable hormonal conditions, the secretory alveolar cell, are retained in most benign lesions, but they are largely lost in invasive carcinomas.

Properties of FNR proteins substituted at each of the five cysteine residues

FNR is a transcriptional regulator controlling the expression of a number of Escherichia coli genes in response to anoxia. It is structurally-related to CRP (the cyclic AMP receptor protein) except for the presence of a cysteine-rich N-terminal extension, which may form part of an iron-binding, redox-sensing domain in FNR. Site-directed substitution has previously shown that four of the cysteine residues (C20, C23, C29 and C122) are essential for FNR function, whereas the fifth (C16) is not. The FNR protein exists in two forms separable by non-reducing SDS-PAGE, and in studies with altered FNR proteins containing single substitutions at each of the five cysteine residues it was concluded that the faster-migrating form (FNR(27)), possesses an intramolecular disulphide bond linking C122 to one of the cysteines near the N-terminus. FNR(27) was more abundant in aerobic cells but the physiological significance of this was not established. Footprint studies indicated that FNR proteins lacking essential cysteine residues are impaired in their ability to protect FNR sites in the ndh promoter. The non-essential cysteine residue (C16) was identified as the source of the most reactive sulphydryl group and all of the inactive proteins exhibited different sulphydryl reactivities. The iron content of the C122A-substituted protein was much reduced but those of the other proteins were less affected. Electrospray mass spectrometry confirmed the accuracy of the gene-derived amino acid composition of FNR with a mutant protein and it showed that a fraction of the wild-type protein may carry a 78 Da substituent which could not be removed with dithiothreitol or beta-mercaptoethanol.

Adolescent Health Status Measurement: Development of the Child Health and Illness Profile

This report describes the early stages in the development and testing of an instrument, known as the CHIP (Child Health and Illness Profile), for assessing the health of individuals aged 11 through 17. The purpose of the instrument is to assess health in epidemiologic surveys, to determine the existence of systematic differences in health in subpopulations (including the socioeconomically disadvantaged), and to provide a basis for assessing the impact of changes in health services or health policies. An instrument consisting of six domains with 25 subdomains was developed based on the literature, the involvement of focus groups and expert panels, and pretesting in four groups of teenagers known to differ in their health. The results of work with panels of experts suggest that the instrument has content validity. Most domains and subdomains had acceptable reliability as measured by α coefficients. Differences in the scores of individuals in the four groups were in the predicted directions, suggesting that the instrument also has construct validity. Additional research is under way to establish other aspects of validity as well as reliability in school populations of adolescents as well as specific clinical settings.

Molecular mapping and detoxification of the lipid A binding site by synthetic peptides

Endotoxin [lipopolysaccharide (LPS)], the major antigen of the outer membrane of Gram-negative bacteria, consists of a variable-size carbohydrate chain that is covalently linked to N,O-acylated beta-1,6-D-glucosamine disaccharide 1,4'-bisphosphate (lipid A). The toxic activity of LPS resides in the lipid A structure. The structural features of synthetic peptides that bind to lipid A with high affinity, detoxify LPS in vitro, and prevent LPS-induced cytokine release and lethality in vivo were defined. The binding thermodynamics were comparable to that of an antigen-antibody reaction. Such synthetic peptides may provide a strategy for prophylaxis and treatment of LPS-mediated diseases.

Aspects of Lactation in the Crab-Eater Seal (Lobodon-Carcinophagus)

Milk samples were obtained from seven crabeater seals (Lobodon carcinophagus) at various stages of lactation. The milk was high in solids (67%), with lipid (51%) accounting for most of the solids and energy. The fatty acid profiles were similar to the milk of other phocid seals and to krill, the major dietary item. Our preliminary results from four animals suggest that about 90 L of milk are transferred from the cow to the pup during the lactation period, estimated to be 17 days in length.

Comparison of the proteoglycanolytic activities of human leukocyte elastase and human cathepsin G in vitro and in vivo

In this study, we evaluated the in vitro and in vivo potency of human leukocyte elastase (HLE) and human cathepsin G (HCG) as proteoglycanases. In vitro evaluation was done using bovine nasal septum aggrecan and aggrecan/hyaluronan aggregate as substrates. Enzyme activity was assessed by the ability of the proteinases to abrogate the ability of aggrecan to aggregate with hyaluronan. In vivo activity of the proteinases was tested by injecting purified HLE and HCG intra-articularly into rabbit stifle joints and quantifying the levels of proteoglycan released into synovial fluids. On a molar basis, HCG was at least tenfold more potent than HLE as a proteoglycanase in vitro. Moreover, HCG was twofold more potent as a proteoglycanase in vivo. In contrast, HLE hydrolyzed elastin approximately 22-fold faster than HCG, but was only slightly more rapid than HCG when [3H]-transferrin was used as substrate. These data indicate that HCG is more potent than HLE as a proteoglycanase both in vitro and in vivo. Thus, HCG could be more important in the pathogenesis of rheumatoid arthritis than previously suspected.

Inhibition of human serine proteases by substituted 2-azetidinones

trans-4-Ethoxycarbonyl-3-ethyl-1-(4-nitrophenyl-sulfonyl)-azetidin -3-one described by Firestone et al. (1990, Tetrahedron 46, 2255) as an inhibitor of human leucocyte elastase (HLE) displayed potent, time-dependent inhibition of both HLE and human cathepsin G (Cat-G). The cis-isomer was 7- and 180-fold less active, respectively. The mechanism likely involves opening of the beta-lactam ring by the active site serine to form an acyl-enzyme intermediate(s). This intermediate partitions with ratios of 4:1 between turnover of the inhibitor and formation of relatively stable enzyme-inhibitor complexes from both enzymes. The final HLE-inhibitor complex reactivated with a half-life of 48 h at 25 degrees C and was 16-fold more stable than the Cat-G-inhibitor complex. The stability of the acyl-enzymes supports a "double hit" chemical mechanism involving both serine acylation and alkylation of the histidine. These observations suggest that beta-lactams may be developed as a class of serine protease inhibitors.

Implications on laboratory workload of breast cancer screening

AIMS

To determine whether the recommended methods for the handling of breast excision biopsy specimens from screening patients cause more laboratory work than those used for non-screening patients.

METHODS

All breast excision biopsy specimens from 1990 were identified. Ninety one came from patients identified during the prevalent round of breast screening. These were compared with 127 from non-screening patients operated on by the same surgeon. The workload in terms of initial blocks taken, cases which needed extra blocks or other additional work, and the time taken for delivery of slides to the pathologist were assessed.

RESULTS

The screening cases required significantly more initial blocks than the non-screening cases (8.03 v 4.95; p = 0.000001). When looking at the malignant diagnoses this difference was maintained (7.74 v 6.02; p = 0.00014).

CONCLUSIONS

Excision biopsy specimens from screening patients require more laboratory work per case than those from non-screening patients. The reasons for these differences lie in the nature of the specimens and their subsequent diagnoses, and in the initial indications for biopsy.

Oxidative degradation of phenanthrene by the ligninolytic fungus Phanerochaete chrysosporium

The ligninolytic fungus Phanerochaete chrysosporium oxidized phenanthrene and phenanthrene-9,10-quinone (PQ) at their C-9 and C-10 positions to give a ring-fission product, 2,2'-diphenic acid (DPA), which was identified in chromatographic and isotope dilution experiments. DPA formation from phenanthrene was somewhat greater in low-nitrogen (ligninolytic) cultures than in high-nitrogen (nonligninolytic) cultures and did not occur in uninoculated cultures. The oxidation of PQ to DPA involved both fungal and abiotic mechanisms, was unaffected by the level of nitrogen added, and was significantly faster than the cleavage of phenanthrene to DPA. Phenanthrene-trans-9,10-dihydrodiol, which was previously shown to be the principal phenanthrene metabolite in nonligninolytic P. chrysosporium cultures, was not formed in the ligninolytic cultures employed here. These results suggest that phenanthrene degradation by ligninolytic P. chrysosporium proceeds in order from phenanthrene----PQ----DPA, involves both ligninolytic and nonligninolytic enzymes, and is not initiated by a classical microsomal cytochrome P-450. The extracellular lignin peroxidases of P. chrysosporium were not able to oxidize phenanthrene in vitro and therefore are also unlikely to catalyze the first step of phenanthrene degradation in vivo. Both phenanthrene and PQ were mineralized to similar extents by the fungus, which supports the intermediacy of PQ in phenanthrene degradation, but both compounds were mineralized significantly less than the structurally related lignin peroxidase substrate pyrene was.

Identification of the posttranslational modifications of bovine lens alpha B-crystallins by mass spectrometry

A combination of mass spectrometric techniques has been used to investigate the amino acid sequence and post-translational modifications of alpha B-crystallin isolated from bovine lenses by gel filtration chromatography and reversed-phase high performance liquid chromatography. Chromatographic fractions were analyzed by electrospray ionization mass spectrometry to determine the homogeneity and molecular weights of proteins in the fractions. The alpha B-crystallin primary gene product, its mono- and diphosphorylated forms, its N- and C-terminal truncated forms, as well as other lens proteins unrelated to the alpha B-crystallins were identified by their molecular weights. Detailed information about the sites of phosphorylation, as well as evidence supporting reassignment of Asn to Asp at position 80, was obtained by analyzing proteolytic digests of these proteins by fast atom bombardment mass spectrometry. Results of this investigation indicate that alpha B-crystallin is phosphorylated in vivo at Ser 45, Ser 59, and either Ser 19 or 21. From the specificity of phosphorylation of alpha-crystallins, it appears that there may be two different kinases responsible for their phosphorylation.

Seasonal Field Energetics of the Rufous Rat-Kangaroo (Aepyprymnus-Rufescens)

Water flux and field metabolic rate (FMR) were measured by the doubly labelled water (DLW) method in free-living male and female rufous rat-kangaroos Aepyprymnus rufescens near Drake in northern New South Wales. The mean FMR of 499 kJ kg-1 day-1 was similar in winter and summer even though the difference in mean minimum temperatures between the two seasons was 20-degrees-C. Furthermore, we did not find any differences in FMR between males and females even though several females carried large pouch young or had young-at-foot. A poor understanding of the diet and the behavioural ecology of A. rufescens makes ft difficult to explain the similarities between sexes and seasons.

Post radiation sarcoma (malignant fibrous histiocytoma) of the cervical spine following ependymoma (a case report)

A case is reported of a 36 y/o man treated with radiation therapy for cervical cord ependymoma who developed malignant fibrous histiocytoma of the cervical spine 15 years later. Pathology revealed the sarcoma adjacent to the recurrent ependymoma. Post-radiation sarcomas following treatment of central nervous system malignancies is discussed.

Ring fission of anthracene by a eukaryote

Ligninolytic fungi are unique among eukaryotes in their ability to degrade polycyclic aromatic hydrocarbons (PAHs), but the mechanism for this process is unknown. Although certain PAHs are oxidized in vitro by the fungal lignin peroxidases (LiPs) that catalyze ligninolysis, it has never been shown that LiPs initiate PAH degradation in vivo. To address these problems, the metabolism of anthracene (AC) and its in vitro oxidation product, 9,10-anthraquinone (AQ), was examined by chromatographic and isotope dilution techniques in Phanerochaete chrysosporium. The fungal oxidation of AC to AQ was rapid, and both AC and AQ were significantly mineralized. Both compounds were cleaved by the fungus to give the same ring-fission metabolite, phthalic acid, and phthalate production from AQ was shown to occur only under ligninolytic culture conditions. These results show that the major pathway for AC degradation in Phanerochaete proceeds AC----AQ----phthalate + CO2 and that it is probably mediated by LiPs and other enzymes of ligninolytic metabolism.