Identification of germ-line E-cadherin mutations in gastric cancer families of European origin

E-cadherin germ-line mutations have recently been described as a molecular basis for early-onset familial gastric cancer in Maori kindred. We screened 18 gastric cancer families of European origin for germ-line mutations to determine the proportion in which E-cadherin mutations occur and the clinical characteristics of the affected families. Truncating mutations were identified in three kindred with familial diffuse gastric cancer. In these families, the age of onset of gastric cancer was variable, the penetrance was incomplete, and one kindred contained individuals with cancers at other sites. Here, we show that a proportion of diffuse gastric cancer families of European origin have germ-line E-cadherin mutations; however, these mutations are absent in intestinal gastric cancer families.     

BRCA2 germline mutations in Swedish breast cancer families

Life-threatening situations in sarcoidosis are extremely rare. They may be due to failure of vital organs--lungs, heart, kidney, liver and brain--and usually due to irreversible fibrosis. Respiratory failure follows irreversible pulmonary fibrosis and the development of cor pulmonale. Cardiac sarcoidosis is more sinister for it may be silent, ill-recognised with sudden death or high morbidity. It needs sophisticated techniques to uncover this latent iceberg. Renal failure may be due to granulomatous interstitial nephritis and/or nephrocalcinosis. Hepatic failure is due to intrahepatic cholestasis, portal hypertension and bleeding oesophageal varices. Neurosarcoidosis carries a mortality of 10 per cent, over twice that of sarcoidosis overall. The treatment of each situation is discussed including organ transplantation.     

Novel germline mutations in the APC gene and their phenotypic spectrum in familial adenomatous polyposis kindreds

Among 23 germline mutations identified in the APC screening of 45 familial adenomatous polyposis (FAP) patients, we have found 10 different novel frameshift mutations in 11 apparently unrelated patients. In two cases, an additional missense mutation was detected. One previously described as a causative germline mutation (S2621C), associated with a 1-bp insertion (4684insA) on the opposite allele, did not segregate with the FAP phenotype in the family and was therefore considered as being non-pathogenic. The other (Z1625H) was located 2 codons before a 1-bp deletion (4897delC). Both mutations were transmitted together from an FAP father to his affected son. The FAP phenotype of these 10 novel truncating mutations was clinically documented within their kindreds. Important variability was observed in the phenotype. Interestingly, we noted that a mutation (487insT) localized at the boundary of the 5' attenuated APC phenotype region in two unrelated families resulted in classical polyposis. A clear-cut genotype-phenotype correlation could be drawn in only two instances. In one family, a 4684insA mutation led to a mild polyposis associated with early inherited osteomas and, in the family bearing the double mutation (Z1625H + 4897delC), the phenotype was obviously a 3' attenuated type. Our data illustrate the wide genetic and phenotypic heterogeneity of this condition between and within the families, making the establishment of correlations complex and any prediction in this disease difficult, although targeting the mutation site may be helpful in some specific cases.     

Characterization of soluble E-cadherin as a disease marker in gastric cancer patients

The soluble fragment of E-cadherin protein (S-ECD) is reported to be increased in the peripheral blood of cancer patients. In this study, we investigated the clinical significance of serum S-ECD in 81 patients with gastric cancer. The amount of serum S-ECD was significantly higher in the gastric cancer patients (4735 +/- 2310 ng ml(-1)) than in healthy volunteers (2515 +/- 744 ng ml(-1)). With the normal range cut-off at average +2 s.d., 67% patients showed abnormally high serum S-ECD levels. This frequency was significantly higher than that of other tumour markers, such as CEA (4.4%) or CA19-9 (13.3%). However, there was no significant correlation between the amount of S-ECD and clinicopathological factors. Serum S-ECD might be derived from cancer tissue, as removal of cancers by surgical treatment results in quick decline of the serum S-ECD and S-ECD can be detected by immunoblot in cancer tissues but not in normal epithelium. The serum S-ECD amount was compared with the E-cadherin expression in cancer tissues, which were classified into those showing preserved (+), partially reduced (+/-) or lost (-) expression. Interestingly, E-cadherin (+/-) tumours showed higher serum S-ECD levels than the other types, and a higher amount of S-ECD in the immunoblot analysis. Thus, the serum level of S-ECD may serve as an excellent tumour marker with high sensitivity. Furthermore, analysis of S-ECD in serum and cancer tissue can offer clues for elucidating the mechanism of reduction of E-cadherin expression in cancer cells.     

Excess of hMLH1 germline mutations in Swiss families with hereditary non-polyposis colorectal cancer

This article describes a high-performance liquid chromatographic (HPLC) method for the measurement of azithromycin (AZI) and two of its metabolites, 9a-N-desmethylazithromycin (ADES) and N-desmethylazithromycin (NDES), in human tears and plasma. The drug, metabolites, and internal standard (n-propylazithromycin [IS]) were detected electrochemically after injection of the extracted sample into the HPLC system. The peak height ratio (AZI, ADES, or NDES to IS) varied linearly, with concentrations in the ranges of 0.1 mg/L to 2.0 mg/L (tears) and 0.01 mg/L to 2.0 mg/L (plasma) of AZI, ADES, and NDES; the correlation coefficient (r) was more than 0.994 mg/L for all of the compounds (n=6). The analysis of tear samples collected at different intervals within 12 hours to 144 hours after a dose of 20 mg/kg of AZI from a trachoma patient yielded concentrations ranging from 1.52 mg/L to 0.34 mg/L for AZI, 0.79 mg/L to 0.27 mg/L for ADES, and 1.99 mg/L to less than 0.20 mg/L for NDES. The concentration of AZI in plasma ranged from 0.15 mg/L to 0.01 mg/L, whereas ADES and NDES were undetectable.     

Low frequency of BRCA1 germline mutations in 45 German breast/ovarian cancer families

Serum samples from 47 men with current condylomas, 32 men with a history of condylomas and from 205 men with no history of genital wart disease, who were attending sexually transmitted disease (STD) clinics at two different hospitals in Stockholm, were analyzed for the presence of immunoglobulin G (IgG) and A (IgA) antibodies to capsids of human papillomavirus types 6 and 11. IgG to HPV type 6 was found among 35% of patients with a history of condylomas compared to 10% of controls (p = 0.0003), but only among 27% of patients with current condylomas. Antibodies to HPV 6 and to HPV 11 showed a very limited correlation, suggesting that the antibodies are HPV-type restricted. The results strengthen conclusions from a previous serological study indicating that IgG antibodies against HPV 6 develop late during condylomatous disease and mostly reflect previous exposure to the virus.     

Secondary breast cancer in patients presenting with osteosarcoma: possible involvement of germline p53 mutations

Second malignancies following treatment for osteosarcoma are unusual. Breast cancer occurring in patients with osteosarcoma has been reported following therapeutic chest irradiation. We now report three cases of breast cancer occurring in young women who were successfully treated for osteosarcoma. These women had not received therapeutic chest irradiation and in two of the three women there was no family history of breast cancer. Peripheral blood was available for study from one case. Of import, this case demonstrated a germline mutation in exon 7 of the tumor suppressor gene, p53. The mutation was detected by constant denaturing gradient gel electrophoresis and confirmed by DNA sequencing. In this particular patient, inactivation of the p53 gene may be involved in the development of both the first and second malignancy.     

Molecular characterization of germline mutations in neurofibromatosis 2 in two families

Neurofibromatosis 2 (NF2) is an autosomal dominant disorder that predisposes patients to central nervous system tumors. It is caused by mutations in the NF2 tumor suppressor gene, which is located on chromosome 22q12. We studied 2 multigenerational NF2 families (three members of family 1 and the proband of the family) by gene mutation analysis and clinical assessment. One member of family 1 had a 169 C-->T point mutation at codon 57 of exon 2 and had a severe phenotype. His father had a silent 1113 C-->T point mutation at codon 371 of exon 11 and had a normal phenotype. The proband of family 2 had a deletion at nucleotide 720 G (codon 240) of exon 8. This led to a frameshift and termination at codon 250, and a severe NF2 phenotype. Our results indicate that clinical abnormalities can be present in carriers. Nonsense and frameshift mutations in the NF2 tumor suppressor gene are associated with phenotypes. The clinical abnormalities can develop at a young age.     

Moderate frequency of BRCA1 and BRCA2 germ-line mutations in Scandinavian familial breast cancer

Previous studies of high-risk breast cancer families have proposed that two major breast cancer-susceptibility genes, BRCA1 and BRCA2, may account for at least two-thirds of all hereditary breast cancer. We have screened index cases from 106 Scandinavian (mainly southern Swedish) breast cancer and breast-ovarian cancer families for germ-line mutations in all coding exons of the BRCA1 and BRCA2 genes, using the protein-truncation test, SSCP analysis, or direct sequencing. A total of 24 families exhibited 11 different BRCA1 mutations, whereas 11 different BRCA2 mutations were detected in 12 families, of which 3 contained cases of male breast cancer. One BRCA2 mutation, 4486delG, was found in two families of the present study and, in a separate study, also in breast tumors from three unrelated males with unknown family history, suggesting that at least one BRCA2 founder mutation exists in the Scandinavian population. We report 1 novel BRCA1 mutation, eight additional cases of 4 BRCA1 mutations described elsewhere, and 11 novel BRCA2 mutations (9 frameshift deletions and 2 nonsense mutations), of which all are predicted to cause premature truncation of the translated products. The relatively low frequency of BRCA1 and BRCA2 mutations in the present study could be explained by insufficient screening sensitivity to the location of mutations in uncharacterized regulatory regions, the analysis of phenocopies, or, most likely, within predisposed families, additional uncharacterized BRCA genes.     

Hereditary nonpolyposis colorectal cancer (HNPCC): eight novel germline mutations in hMSH2 or hMLH1 genes

The World Health Organization criteria for the diagnosis of Osteopenia and Osteopoposis was applied to a control group of 33 females ages 50 to 59 years and 24 females ages 60 to 69 years. The general exclusion criteria for the selection of subjects included early menopause and diseases, use of drugs and toxic habits such as smoking and alcoholism, known to affect bone and mineral metabolism. Bone mineral densities were measured with a DEXA Hologic, model 1000. In the reference population mean peak bone mineral density expressed in g/cm2 was 1.051 (SD = 0.119) for the lumbar spine at age 30 to 39 years and for the femoral neck 0.861 (SD = 0.098) at age 20 to 29 years. Bone densities below 1 to 2.5 SD from mean peak bone mass ranged from 0.932 to 0.754 g/cm2 in the lumbar spine and 0.763 to 0.616 g/cm2 for the femoral neck. The mean age of the pooled group was 58.4 years. The prevalence of osteopenia in the pooled group was 42 % for the lumbar spine and 56% for the femoral neck and of osteoporosis, 12% for the lumbar spine and 8.7% for the femoral neck. A similar prevalence has been found by other investigators in hispanic populations. Such a high percentage of females with osteopenia implicates that bone densitometry must be done in the perimenopausal years and in young individuals at risk so as to proceed with early medical intervention to prevent osteoporosis.     

Clinicopathological significance of altered loci of replication error and microsatellite instability-associated mutations in gastric cancer

Replication errors (RERs) judged by microsatellite instability and its associated mutations have been recognized as an important mechanism in tumorigenesis of gastric cancers (GCs). To gain a deeper insight into its significance, we examined the frequency of RERs using nine microsatellite markers and screened mutations in the polydeoxyadenine tract of the transforming growth factor beta type II receptor gene (TGF-betaRII) and polydeoxyguanine tracts of insulin-like growth factor II receptor and BAX genes. Twenty-four (30%) of 80 patients with GC had RERs, of which 3, 8, and 13 had one, two, and three or more loci, respectively. In 13 tumors with RERs in three or more loci, frameshift mutations of TGF-betaRII, insulin-like growth factor II receptor, and BAX were identified in 12, 3, and 2, respectively. Compared with GC with none, one or two RER-positive loci as a group, GC with RERs in three or more loci showed a significantly higher frequency of antral location (12 of 13 versus 35 of 67; P = 0.01), intestinal subtype (11 of 13 versus 30 of 67; P = 0.01), and previous Helicobacter pylori infection (12 of 13 versus 41 of 67; P = 0.05) and a lower incidence of lymph node metastasis (5 of 13 versus 49 of 67; P = 0.02) and tended to be in an advanced stage (12 of 13 versus 54 of 67; P = 0.28). These data indicate that GC with multiple RERs manifest distinct clinicopathological characteristics, and that a high frequency of frameshift mutations involving the TGF-betaRII gene may be causatively linked with tumorigenesis and progression.     

Identification of missense and truncating mutations in the BRCA1 gene in sporadic and familial breast and ovarian cancer

Bone loss after oophorectomy of adult rats is more rapid and complete in the metaphysis than in the epiphysis of the femur, particularly in the proximal region of the metaphysis distant from the growth plate. This study was undertaken to determine the effects of prepubertal oophorectomy, on femoral cancellous bone acquisition during growth. Rats were oophorectomized (OVX) or sham operated at 3 weeks of age and killed at intervals up to 78 weeks for scanning electron microscopy and histomorphometry of the distal femur. Differences in cancellous bone architecture between the two groups was evident after 6 weeks of age. Relatively minor differences were found in the part of the metaphysis near the growth plate and in the epiphysis, with less trabeculae in the primary spongiosa and 1 to 2 less trabeculae/mm in the secondary spongiosa. However, as metaphyseal growth proceeded, trabeculae were present for a greater distance up the femoral shaft in controls than in OVX rats, with mean BV/TV in the proximal part of the metaphysis increasing from 1.4% at 6 weeks to 13.4% at 20 weeks in controls, with no increase in the OVX rats. We find that the lack of ovarian hormones increases the rate of destruction of trabeculae near the metaphyseal-diaphyseal junction.     

Astrocytomas and choroid plexus tumors in two families with identical p53 germline mutations

Germline p53 mutations carry an increased risk of development of breast cancer, soft tissue and osteosarcomas, brain tumors, leukemia and adrenocortical carcinomas. Cerebral neoplasms are usually of astrocytic lineage and occur in 40% of affected families. This report presents clinical, neuropathological and molecular genetic data from 2 families in France with an identical p53 germline mutation in codon 248 (CGG->TGG; Arg->Trp) and a clustering of CNS tumors. The youngest patient in each family developed a malignant choroid plexus tumor while several young adults of both kindred succumbed to low-grade astrocytoma, anaplastic astrocytoma or glioblastoma. The only non-neural neoplasm was an adrenocortical carcinoma in a boy aged 4 years who developed an anaplastic choroid plexus papilloma 2 years later. Of 2 previously reported inherited choroid plexus tumors, 1 occurred in a family which also carried a germline mutation in codon 248. It remains to be shown whether this unusual pattern of CNS tumors is due to an organ-specific effect of this particular p53 mutation or whether it reflects the genetic background of the affected families.     

Expression of E-cadherin in primary and metastatic prostate cancer

Immunohistochemical studies have suggested that E-cadherin may be a useful prognostic marker in prostate cancer. Previous studies have depended on cryostat sections of tissues selected grossly. Many prostate cancers, even when extensive, are not visible grossly; many others cannot be demarcated sharply grossly. The wide applicability of prognostic markers after total prostatectomy will depend upon methods that can be applied to tissue selected based upon the histopathological examination of the entire prostate. Our purpose was to investigate the possibility that E-cadherin could be demonstrated in paraffin-embedded whole prostates and metastatic prostate cancer. Microwaving in citrate buffer was the best of five methods tested for the demonstration of E-cadherin in paraffin-embedded prostate and was used to investigate 53 primary prostate cancers from 44 patients and lymph node metastases from 14 patients. Metastases of prostate cancer to lymph nodes expressed less (P = 0.008) E-cadherin than primary prostate cancers. The expression of E-cadherin correlated with the histopathological differentiation (Gleason grade) of primary prostate cancers (P = 0.03, Ptrend = 0.003). The use of monoclonal anti-human E-cadherin (HECD-1) with microwaving in citrate buffer followed by immunoperoxidase staining with heavy metal enhancement for the demonstration of E-cadherin in paraffin-embedded tissue will, for the first time, allow the use of archival tissue for prognostic studies of E-cadherin in prostate cancer and other tissue. Our results are consistent with the hypothesis that aggressive prostate cancers exhibit decreased expression of E-cadherin and demonstrate the feasibility of long-term prognostic studies of this molecule in the usually multiple prostate cancers found in whole, formalin-fixed, paraffin-embedded resected prostates.     

Somatic NF2 gene mutations in familial and non-familial vestibular schwannoma

Vestibular schwannoma occurs both as a sporadic tumour and in the dominantly inherited familial cancer syndrome neurofibromatosis type 2 (NF2). The gene for NF2 has recently been isolated on chromosome 22, and the demonstration of inactivating germline mutations in NF2 patients and NF2 associated tumours suggests that it act as a tumour suppressor. We have investigated 85 sporadic and 2 NF2 associated vestibular schwannomas, and one vagal schwannoma for chromosome 22 allele loss and NF2 gene mutations. A further 7 vestibular schwannomas were investigated for NF2 mutations only. Chromosome 22 allele loss was detected in 34 of 87 vestibular schwannomas and in the vagal nerve schwannoma. Six exons of the NF2 gene were investigated by SSCP analysis in all 95 tumours. Somatic NF2 gene mutations were detected in 13 non-familial vestibular schwannomas and in one of the NF2 vestibular schwannomas. Seven non-familial tumours with an NF2 gene mutation also displayed a chromosome 22 allele loss. Thirteen of the mutations were predicted to produce truncation of the NF2 protein. These results suggest that somatic mutations of the NF2 tumour suppressor gene are a critical step in the pathogenesis of both familial and non-familial vestibular schwannoma and that the mechanism of tumourigenesis complies with a 'two-hit' mutation model.     

Independent constitutional germline mutations occurring in the RB1 gene in cousins with bilateral retinoblastoma

The inheritance of a genetic susceptibility to the development of retinoblastoma generally follows an autosomal mode of inheritance with high penetrance. Rare families, however, show evidence of incomplete penetrance where individuals can transmit the mutant gene without being affected themselves. In these families formal proof of this dogma requires the identification of the predisposing mutation. In this study we have identified the mutations in cousins with bilateral (hereditary) disease. Using SSCP and DNA sequencing, different constitutional mutations were detected in the affected cousins in this pedigree. One cousin carries a C-->T mutation in exon 8 generating a stop codon directly which was also present in his affected mother whereas the other cousin carries an 8 base pair deletion in exon 20. Neither half of the family carried the same mutation as the other. The mother of the patient with the 8 bp deletion carried neither of the mutations. Thus, we have demonstrated that the retinoblastomas in this family have developed as a result of independent, sporadic genetic events which occurred coincidentally in the same extended family rather than being due to a common mutation which manifests as incompletely penetrant. These observations have important implications for genetic counselling in this type of family.     

Early gastric cancer mimicking advanced gastric cancer

The clinicopathological features of 37 early gastric cancers mimicking advanced gastric cancer were reviewed retrospectively, and were compared with 596 other early gastric cancers and 126 mp gastric cancers, defined as gastric cancer invading the muscularis propria of the stomach. A greater tumour size (P < 0.005), submucosal invasion (P < 0.005), lymph node and lymph vessel invasion (P < 0.005) and vascular invasion (P < 0.025) were found more frequently in early gastric cancers mimicking advanced gastric cancers than in other early gastric cancers. There were no significant differences in the clinicopathological findings between early gastric cancers mimicking advanced gastric cancers and mp gastric cancers. Patients with early gastric cancers mimicking advanced gastric cancers showed a lower survival rate than patients with other early gastric cancers, but a higher survival than those with mp gastric cancers. The macroscopic appearance of an advanced gastric cancer was an indicator of massive submucosal invasion and lymph node metastasis in early gastric cancer. As early gastric cancers mimicking advanced gastric cancers showed similar clinicopathological findings to mp gastric cancers, these cancers should be treated as mp gastric cancers.