Clinical findings with implications for genetic testing in families with clustering of colorectal cancer

BACKGROUND

Germ-line mutations in DNA mismatch-repair genes (MSH2, MLH1, PMS1, PMS2, and MSH6) cause susceptibility to hereditary nonpolyposis colorectal cancer. We assessed the prevalence of MSH2 and MLH1 mutations in families suspected of having hereditary nonpolyposis colorectal cancer and evaluated whether clinical findings can predict the outcome of genetic testing.

METHODS

We used denaturing gradient gel electrophoresis to identify MSH2 and MLH1 mutations in 184 kindreds with familial clustering of colorectal cancer or other cancers associated with hereditary nonpolyposis colorectal cancer. Information on the site of cancer, the age at diagnosis, and the number of affected family members was obtained from all families.

RESULTS

Mutations of MSH2 or MLH1 were found in 47 of the 184 kindreds (26 percent). Clinical factors associated with these mutations were early age at diagnosis of colorectal cancer, the occurrence in the kindred of endometrial cancer or tumors of the small intestine, a higher number of family members with colorectal or endometrial cancer, the presence of multiple colorectal cancers or both colorectal and endometrial cancers in a single family member, and fulfillment of the Amsterdam criteria for the diagnosis of hereditary nonpolyposis colorectal cancer (at least three family members in two or more successive generations must have colorectal cancer, one of whom is a first-degree relative of the other two; cancer must be diagnosed before the age of 50 in at least one family member; and familial adenomatous polyposis must be ruled out). Multivariate analysis showed that a younger age at diagnosis of colorectal cancer, fulfillment of the Amsterdam criteria, and the presence of endometrial cancer in the kindred were independent predictors of germ-line mutations of MSH2 or MLH1. These results were used to devise a logistic model for estimating the likelihood of a mutation in MSH2 and MLH1.

CONCLUSIONS

Assessment of clinical findings can improve the rate of detection of mutations of DNA mismatch-repair genes in families suspected of having hereditary nonpolyposis colorectal cancer.

Familial and hereditary non-polyposis colorectal cancer: issues relevant for surgical practice

About 15% of patients with colorectal cancer report a family history of this disease. An estimated 1%-5% of patients have hereditary non-polyposis colorectal cancer (HNPCC). Recently, DNA mismatch repair genes associated with this syndrome were identified. For about 50% of families in which HNPCC occurs, DNA-based diagnosis and presymptomatic DNA testing are now feasible. Diagnosis of a hereditary tumour syndrome is relevant for both the patient with cancer and his or her close relatives. The complexities of family studies warrant the forming of a multidisciplinary team which may choose to work within a specialized cancer family clinic.

Markers of oxidative stress and antioxidant activity in plasma and erythrocytes in neonatal respiratory distress syndrome

Markers of oxidative stress and antioxidant activity in plasma and erythrocytes were studied for 14 d after birth in infants with neonatal respiratory distress syndrome (n = 9) and controls (n = 36). In plasma, the total radical trapping antioxidant capacity and the chain-breaking antioxidants vitamin C, sulfhydryl groups and bilirubin were similar. The differences in uric acid levels were not consistent, but vitamin E levels and vitamin E/total-lipid ratio were lower in the neonatal respiratory distress group (p < 0.01). In erythrocytes, the antioxidant enzymes glutathione peroxidase, glutathione reductase and superoxide dismutase did not differ postnatally. Indicators of oxidative damage in plasma (sulfhydryl/protein ratio and thiobarbituric acid reactive substances) showed the same postnatal course in both groups and were not influenced by oxygen therapy. In erythrocytes the reduced/oxidized glutathione ratio showed no consistent differences. In conclusion, this study, using erythrocytes and plasma, does not provide convincing evidence of oxidative damage and diminished antioxidant defenses in preterm infants with neonatal respiratory distress syndrome.

Molecular analysis of the APC gene in 105 Dutch kindreds with familial adenomatous polyposis: 67 germline mutations identified by DGGE, PTT, and southern analysis

Germline mutations of the adenomatous polyposis coli (APC) gene are responsible for familial adenomatous polyposis (FAP), an autosomal dominant predisposition to colorectal cancer. We screened the entire coding region of the APC gene for mutations in an unselected series of 105 Dutch FAP kindreds. For the analysis of exons 1-14, we employed the GC-clamped denaturing gradient gel electrophoresis (DGGE), while the large exon 15 was examined using the protein truncation test. Using this approach, we identified 65 pathogenic mutations in the above 105 apparently unrelated FAP families. The mutations were predominantly either frameshifts (39/65) or single base substitutions (18/65), resulting in premature stop codons. Mutations that would predict abnormal RNA splicing were identified in seven cases. In one of the families, a nonconservative amino acid change was found to segregate with the disease. In spite of the large number of APC mutations reported to date, we identified 27 novel germline mutations in our patients, which reiterates the great heterogeneity of the mutation spectrum in FAP. In addition to the point mutations identified in our patients, structural rearrangements of APC were found in two pedigrees, by Southern blot analysis. The present study indicates that the combined use of DGGE, protein truncation test, and Southern blot analysis offers an efficient strategy for the presymptomatic diagnosis of FAP by direct mutation detection. We found that the combined use of the currently available molecular approaches still fails to identify the underlying genetic defect in a significant subset of the FAP families. The possible causes for this limitation are discussed.

Cancer risk in families with hereditary nonpolyposis colorectal cancer diagnosed by mutation analysis

BACKGROUND & AIMS

Hereditary nonpolyposis colorectal cancer is characterized by early-onset colorectal cancer and the occurrence of various other cancers. The recent isolation of four mismatch repair genes responsible for hereditary nonpolyposis colorectal cancer allows for the identification of carriers within affected families. The purpose of this study was to assess the age-specific cancer risk in a large series of gene carriers.

METHODS

Thirty-four families were studied by mutation analysis. In 19 of these families, pathogenic mutations were found at hMSH2 or hMLH1. Of 382 relatives, 124 had a mutation in hMLH1 and 86 in hMSH2.

RESULTS

The lifetime risk of colorectal cancer was the same in both groups of gene carriers (80%). The risk of endometrial cancer was greater in hMSH2 gene carriers compared with hMLH1 gene carriers (61% vs. 42%), but the difference was not statistically significant. A very high relative risk of cancer of the small bowel (relative risk of >100) was observed in carriers of either gene. Only the carriers of hMSH2 mutations had a significantly increased relative risk of cancer of the urinary tract (kidney and ureter) (relative risk of 75.3), stomach (relative risk of 19.3), and ovaries (relative risk of 8.0).

CONCLUSIONS

This study provides estimates of cancer risk that may contribute to the appropriate management of gene carriers within families with hereditary nonpolyposis colorectal cancer.

Genetic counseling in hereditary nonpolyposis colorectal cancer

Recent identification of gene mutations responsible for hereditary nonpolyposis colorectal cancer (HNPCC) has made possible the presymptomatic diagnosis of at-risk family members. If DNA testing shows that a family member is a gene carrier, that individual's lifetime cancer risk is approximately 90%. If the test is negative, the family member's cancer risk drops to that of the general population. Presymptomatic DNA-based diagnosis consists of pretest counseling, the actual DNA test, and posttest counseling. Pretest counseling focuses on the benefits, limitations, and possible adverse effects of testing, and the advantages and drawbacks of screening methods. Posttest counseling sessions explore the test result, and family members' reactions to it. A multidisciplinary team approach is necessary for the management of HNPCC families.

Endometrial cancer in four sisters: report of a kindred with presumed cancer family syndrome

Hereditary nonpolyposis colorectal cancer (HNPCC, synonyms: cancer family syndrome, Lynch syndrome) is characterized by the occurrence of colorectal cancer and other primary tumors in susceptible family members. Inheritance is autosomal dominant with high penetrance. Endometrial cancer is the most frequent extracolonic malignancy in gene carriers. The criteria for the diagnosis HNPCC include the occurrence of colorectal cancer in three close relatives. However, not only colorectal cancer but also endometrial cancer may indicate HNPCC. We present a family diagnosed as a probable HNPCC kindred after endometrial cancer was observed in four sisters. One of these patients and the father of the four sisters had had colorectal cancer. This kindred illustrates the importance of recording the family history in patients with endometrial cancer.

A simplified grading method of transitional cell carcinoma of the urinary bladder: reproducibility, clinical significance and comparison with other prognostic parameters

OBJECTIVE

To determine the extent to which the biological potential of transitional cell neoplasms can be predicted by histological grading of the primary tumour in a two grade system using simple histological criteria and to evaluate the additional value of grading when combined with other prognostic factors. The inter-observer variability of the World Health Organization grading and the two grade system was tested.

PATIENTS AND METHODS

The study included 311 patients with newly diagnosed transitional cell carcinoma of the urinary bladder. Two-hundred and fifty-six patients (82.3%) were men and 55 (17.7%) were women. Age ranged from 17 to 92 years with a mean of 66 years. The median follow-up was 38 months, with a maximum of 150 months (mean 46.2 months).

RESULTS

A simplified grading system was developed in which only low-grade and high-grade tumours were distinguished. Reproducibility of this grading system was good to excellent with a group kappa value of 0.78. The survival of patients with low-grade tumours was significantly better than that of patients with high-grade tumours (P < 0.0001). The progression-free interval was also significantly longer in patients with low-grade tumours than in patients with high-grade tumours (P = 0.0032). Combining low-high grading, histological stage, mitotic index and age, histological stage appeared to be the most important parameter in predicting survival and progression.

CONCLUSION

A reproducible and discriminating system such as this low-high grade system is an important prognostic factor when stage cannot be established with certainty.

Persistence of host-type hematopoiesis after allogeneic bone marrow transplantation for leukemia is significantly related to the recipient's age and/or the conditioning regimen, but it is not associated with an increased risk of relapse

We investigated the chimerism pattern within flow-sorted peripheral blood- or bone marrow-derived cell populations after allogeneic bone marrow transplantation (BMT) for the treatment of leukemia in children. This study was performed to define the identity of persistent host-type cells, to identify prognostic variables for the persistence of host-type hematopoiesis, and to determine the prognostic significance of the chimerism pattern on the duration of the leukemia-free interval, the overall survival, and the leukemia-free survival. The patients received either HLA-identical non-T-cell-depleted (n = 46) or HLA nonidentical T-cell-depleted (n = 7) BMT. In the peripheral blood, the children showed either stable mixed chimerism (SMC; ie, persistent host-type hematopoiesis; n = 14), (transient) mixed T-lymphoid chimerism (MTLC; n = 9), or complete chimerism (CC; n = 30). In the bone marrow, only donor-type cells were found in children with either CC (n = 8) or MTLC (n = 2), and a mixture of donor- and recipient-type cells was found in children with SMC (n = 7). The persistence of host-type hematopoiesis (SMC) was significantly related to a lower age of the recipient, the type of conditioning regimen, a lower total body irradiation dose, T-cell depletion of the bone marrow graft, and the use of cyclosporine A for acute graft-versus-host disease prophylaxis. No significant differences were found between patients with (SMC) or without (CC/MTLC) persistent host-type hematopoiesis with respect to the duration of the leukemia-free interval, the overall survival, or the leukemia-free survival. We conclude that ablation of host-type hematopoiesis is not compulsory for long-term leukemia-free survival after allogeneic BMT for various hematologic malignancies.

Paternal duplication of chromosome 5q11.2-5q14 in a male born with craniostenosis, ear tags, kidney dysplasia and several other anomalies

A de novo duplication of the proximal part of the long arms of chromosome 5 was found in a male born with craniostenosis, ear tags and kidney dysplasia. The nature of the chromosomal aberration was defined by fluorescence in situ hybridization and the origin of the duplication was traced by polymorphic DNA markers. A comparison is made with the published cases showing similar duplications in the long arm of chromosome 5.

Mixed T-lymphoid chimerism after allogeneic bone marrow transplantation for hematologic malignancies of children is not correlated with relapse

We performed polymerase chain reaction-variable number of tandem repeats analysis of flow-sorted peripheral blood T-, B-, natural killer-, and myeloid cell populations (van Leeuwen et al, Br J Haematol 79:218, 1991) in 32 children following allogeneic bone marrow transplantation (BMT) for leukemia to evaluate the relationship between mixed lymphoid chimerism and leukemia relapse. Five patients showed a stable mixed chimerism pattern characterized by the presence of both recipient as well as donor type cells in all cell populations up to 1 year posttransplantation. Five others showed transient mixed chimerism in the T-lymphoid cell lineage. In one patient, host T cells persisted until leukemia relapse. The remaining 21 patients showed a complete chimerism throughout the period of investigation. Twenty-five of these patients were classified according to the presence (n = 10) or absence (n = 15) of recipient type T cells. Statistical analysis did not show significant differences in the distribution of a number of clinical variables between the two groups, nor in the actuarial survival (P = .11) and leukemia-free interval (P = .97). Therefore, these results suggest that persistence of recipient type T lymphoid cells after allogeneic BMT for hematologic malignancies is not correlated with leukemia relapse. In addition, we observed that persistence of host cells within the original leukemia cell lineage and at the correct maturational stage was predictive for leukemia relapse in one case.

DNA aneuploidy and cell proliferation in relation to histology and prognosis in patients with Hodgkin's disease

BACKGROUND

Aneuploidy and S-phase fraction are well recognized prognostic features of solid tumors and non-Hodgkin's lymphoma. However, only limited data on Hodgkin's disease are available.

PATIENTS AND METHODS

In this study flow cytometric data on ploidy status and S-phase fraction are analyzed in relation to clinical characteristics and prognosis in 137 patients with Hodgkin's disease.

RESULTS

The presence of DNA aneuploidy was not associated with other clinical characteristics. When the histologic subtypes were clustered according to a higher number of Reed-Sternberg/Hodgkin cells into two classes (LP + NSI and the histologic NSII + MC + LD), it appeared that cases with an SPF > or = 7.5% had the histologic subtypes NSII + MC + LD significantly more frequently than those with an SPF < 7.5% (P = 0.001). There was no significant difference in complete remission rates, relapse-free or overall survivals between the patients with diploid and those with aneuploid lymph nodes. The complete remission rate for patients with and SPF < 7.5% was higher than for those with an SPF > or = 7.5%, 95% (56/59) and 76% (50/66), respectively (P = 0.006). The 10-year survival rate was 78% for patients with an SPF < 7.5% and 48% for those with an SPF > or = 7.5% (P = 0.04). However, by multivariate analysis only the ESR, age and clinical stage proved to be of independent prognostic importance.

CONCLUSION

DNA aneuploidy did not correlate with known prognostic factors or survival, but the SPF might turn out to be an indicator of patients who will have less favourable outcomes.

Hodgkin disease in the elderly. A registry-based analysis

Limited data regarding the cause of the age-related decrease in survival times in patients with Hodgkin disease are available. In a retrospective study of a nonselected population of patients with Hodgkin disease, the authors evaluated which factors contributed to the age-related prognostic effect in this disease. The survival curves of 182 patients were compared, and survival time was found to decrease markedly after the age of 50 years. Differences in disease characteristics between older and younger patients were small and not statistically significant. Significantly fewer older patients received adequate treatment (34% versus 2%), and they were less likely to have complete disease remission (61% versus 90%). However, the relapse-free survival time of patients with complete disease remission was not significantly different from that of younger patients, 50% of all patients being free of disease after 10 years. Intercurrent disease did not appear to be responsible for decreased survival times in the elderly (32% versus 26%). The authors conclude that the inability to give adequate treatment seems to be the major determinant of the poorer overall survival time of older patients with Hodgkin disease.

Detection of mixed chimaerism in flow-sorted cell subpopulations by PCR-amplified VNTR markers after allogeneic bone marrow transplantation

The amplification of Variable Number of Tandem Repeats (VNTR) by the polymerase chain reaction (PCR) was used to determine the extent of chimaerism in flow sorted lymphoid and myeloid cell populations following allogeneic bone marrow transplantation (BMT). Pre-BMT screening with a set of five VNTR revealed that at least one marker was maximally informative in 95% of donor-recipient pairs. Mixing reconstruction experiments indicated that detection of 1-5% of the minor cell population in a sample of 5 x 10(3) nucleated cells is feasible. Flow sorted post-transplant peripheral blood B- and T-lymphocyte, natural killer and monocyte cell populations were subjected to PCR-VNTR marker analysis. It was shown that this procedure can be used for the early detection of engraftment and the identification of mixed chimaerism in various haematopoietic cell lineages in patients with leukaemia or severe combined immune deficiency, treated with allogeneic BMT.

A new deletion polymorphism at D5S71 raises the linkage information on adenomatous polyposis coli: implications for presymptomatic diagnosis

Two independent study-groups, one in Britain and the other in the United States, were the first to report linkage between APC and a TaqI restriction fragment length polymorphism (RFLP) at D5S71 (probe C11p11) on chromosome 5q. They found no recombinants in about 50 informative meioses. The same TaqI RFLP was found to be uninformative for linkage in 15 Dutch polyposis families. The recently reported four base-pair deletion polymorphism (DEL1) at D5S71 has raised the polymorphism information content of this marker from 0.17 to 0.40 in the Dutch population. Seven of 20 polyposis families screened for the DEL1 as well as the TaqI polymorphism gave a combined peak lod score of 5.68 with no recombinants in 37 informative meioses. These data, together with those so far reported in the literature, raise the peak lod score to 17.09 at a recombination fraction of 0.05, the 95% upper confidence limit being 0.09. In combination with the use of another informative marker, D5S81 (probe YN5.48) closely mapping on the other side of APC, the presymptomatic diagnosis of the disease can be made with more than 99.9% certainty. It has to be stressed, however, that the the possible existence of more than one polyposis locus cannot, as yet, be excluded.

Human alpha B-crystallin (CRYA2) gene mapped to chromosome 11q12-q23

The alpha B-crystallin gene (CRYA2) encodes the abundant lens protein alpha B-crystallin. A panel of human/rodent hybrid cell lines, derived from five different parental combinations, was characterized with respect to human chromosomal content and the presence of well-established human chromosome-specific markers. This panel was screened for the presence of CRYA2, using the third exon of the hamster alpha B-crystallin gene as a probe. The patterns of segregation of CRYA2 with individual human chromosomes show the highest degree of concordance between CRYA2 and chromosome 11. Using cell hybrids containing translocated and/or partially deleted human chromosomes, the CRYA2 gene was localized to 11q12-11q23.

Assignment of the human gene for histidine-rich glycoprotein to chromosome 3

Histidine-rich glycoprotein (HRG) is a monomeric plasma glycoprotein involved in the modulation of coagulation and fibrinolysis. Using Southern analysis of human-rodent somatic cell hybrid DNA with a human HRG-specific cDNA probe, the HRG gene was assigned to chromosome 3. One hybrid that was known to contain only a segment of chromosome 3 also reacted positively with the HRG probe. Hybridization analysis with a set of chromosome 3-specific probes showed that the segment of chromosome 3 present in this hybrid is missing the region pter-p14, which indicates that HRG is not located in this region. No restriction fragment length polymorphisms were detected for HRG with 10 commonly used restriction enzymes.

Solid-phase adsorption of antigens for efficient production of antibodies reactive with native and fixed tissue antigens

A study has been made of the efficacy of different immunization protocols using low antigen levels for the generation of monoclonal antibodies capable of detecting antigens (ADCP) in processed tissues. Protocols using unprocessed native antigen immobilized on nitrocellulose were more efficient than soluble antigen in generating serum antibodies reactive with both native antigen and processed tissues. The derived monoclonal antibodies reacted with native but not processed antigen. The use of antigen immobilized on polyvinylidene (PVDF) and subsequently processed as for histochemistry was successful in generating monoclonal antibodies reactive with processed antigen.

Presymptomatic diagnosis of familial adenomatous polyposis by bridging DNA markers

Familial adenomatous polyposis (FAP) is a disorder with autosomal dominant inheritance, which predisposes to colorectal adenocarcinoma. The gene causing the disorder has been assigned to chromosome 5 by means of a polymorphic DNA marker called C11p11. An informative Dutch pedigree showed that two other linked polymorphic DNA markers, Pi227 and YN5.48, closely flank the FAP locus, one on either side. This finding will allow prenatal and presymptomatic diagnosis of FAP, with more than 99.9% reliability in the majority of families, by means of already available markers.

Distribution of adenosine deaminase complexing protein (ADCP) in human tissues

The normal distribution of adenosine deaminase complexing protein (ADCP) in the human body was investigated quantitatively by ADCP-specific radioimmunoassay (RIA) and qualitatively by immunohistochemistry. In these studies we used a specific rabbit anti-human ADCP antiserum. In all 19 investigated tissues, except erythrocytes, ADCP was found by RIA in the soluble and membrane fractions. From all tissues the membrane fractions contained more ADCP (expressed per mg protein) than the soluble fractions. High membrane ADCP concentrations were found in skin, renal cortex, gastrointestinal tract, and prostate. Immunoperoxidase staining confirmed the predominant membrane-associated localization of the protein. In serous sweat glands, convoluted tubules of renal cortex, bile canaliculi, gastrointestinal tract, lung, pancreas, prostate gland, salivary gland, gallbladder, mammary gland, and uterus, ADCP immunoreactivity was found confined to the luminal membranes of the epithelial cells. These data demonstrate that ADCP is present predominantly in exocrine glands and absorptive epithelia. The localization of ADCP at the secretory or absorptive apex of the cells suggests that the function of ADCP is related to the secretory and/or absorptive process.

Distribution of adenosine deaminase-complexing protein in murine tissues

It has been suggested that mouse and rat lack adenosine deaminase-complexing protein because in these species exclusively the small molecular weight form of adenosine deaminase (ADA-S) is found. This suggestion is based on the assumption that the adenosine deaminase binding capacity is an inherent functional characteristic of adenosine deaminase-complexing protein. We report on the presence of adenosine deaminase-complexing protein immunoreactivity in mouse and rat determined with a species cross-reactive polyclonal anti-adenosine deaminase-complexing protein serum. In the mouse the tissue and subcellular distribution and the electrophoretic mobility in starch and polyacrylamide gels of the protein correspond with those of adenosine deaminase-complexing protein, but it does not bind the small molecular weight form of adenosine deaminase. Furthermore, in human, mouse, and rat kidney cortex adenosine deaminase and adenosine deaminase-complexing protein did not colocalize by immunohistochemistry. It is suggested that the function of adenosine deaminase-complexing protein is not adenosine deaminase-related.

Exclusion of the dysplastic nevus syndrome (DNS) locus from the short arm of chromosome 1 by linkage studies in Dutch families

Familial dysplastic nevus syndrome (DNS) is an autosomal dominant premalignant condition characterized by multiple large moles of variable size and color and a strongly increased risk for cutaneous malignant melanoma. In order to determine the chromosomal localization of the DNS gene, linkage studies were initiated in six large Dutch families. No support was obtained for linkage between the loci for DNS and the rhesus blood group on chromosome 1. Data from additional markers (DNF15S1, D1Z2, FUCA1, D1S17, D1S57, and PGM1) make it possible to exclude the DNS gene from the short arm of chromosome 1 in these Dutch families.

Structure of the bovine eye lens gamma s-crystallin gene (formerly beta s)

The organization of a number of crystallin genes has already been resolved. One of the remaining genes of which the structure was hitherto unknown is the gamma s gene (formerly beta s). We determined the complete sequence of the bovine gamma s-crystallin-coding gene, apart from the middle region of the first intron. Since it contains three exons and two introns, we conclude that the former beta s, also at the gene level is gamma-crystallin-like. However, it is located on chromosome 3, in contrast to other gamma genes which occur in tandem on the human chromosome 2.

Grades of nodular sclerosis (NSI-NSII) in Hodgkin's disease. Are they of independent prognostic value?

Subclassification of the nodular sclerosis (NS) type of Hodgkin's disease in Grade 1 and 2 was reported for the first time by the British National Lymphoma Investigation (BNLI). Three groups, the BNLI, Gärtner et al. and the current authors, found clearly different survival rates between Grade 1 and 2 NS patients. The authors studied retrospectively if this NS grading has an independent prognostic value in 90 NS patients, diagnosed in ten hospitals in the southeastern part of the Netherlands (1972-1983). In this study there is no significant difference in sex, age, B-symptoms, erythrocyte sedimentation rate (ESR), stage, positive laparotomy, involvement of mediastinum or spleen, lymphocyte count, and percentage of complete remissions between the NS subgroups. Multivariate analysis suggests that the subclassification of NS in Grades 1 and 2 is a prognostic factor in survival independent of age, stage and ESR. This finding and the high relative frequency of NS makes application of this NS subdivision probably clinically useful to identify patients for a risk-adapted therapy.