Shunji Yamamori

Deletions and epimutations affecting the human 14q32.2 imprinted region in individuals with paternal and maternal upd(14)-like phenotypes.

Human chromosome 14q32.2 carries a cluster of imprinted genes including paternally expressed genes (PEGs) such as DLK1 and RTL1 and maternally expressed genes (MEGs) such as MEG3 (also known as GTL2), RTL1as (RTL1 antisense) and MEG8 (refs. 1,2), together with the intergenic differentially methylated region (IG-DMR) and the MEG3-DMR. Consistent with this, paternal and maternal uniparental disomy for chromosome 14 (upd(14)pat and upd(14)mat) cause distinct phenotypes. We studied eight individuals (cases 1–8) with a upd(14)pat-like phenotype and three individuals (cases 9–11) with a upd(14)mat-like phenotype in the absence of upd(14) and identified various deletions and epimutations affecting the imprinted region. The results, together with recent mouse data, imply that the IG-DMR has an important cis-acting regulatory function on the maternally inherited chromosome and that excessive RTL1 expression and decreased DLK1 and RTL1 expression are relevant to upd(14)pat-like and upd(14)mat-like phenotypes, respectively.

Metabolic disposition of pantoprazole, a proton pump inhibitor, in relation to S-mephenytoin 4′-hydroxylation phenotype and genotype*

To assess the possible relationship between the metabolic disposition of pantoprazole and genetically determined S‐mephenytoin 4′‐hydroxylation phenotype and genotype.

Gene structure of human cholecystokinin (CCK) type-A receptor: body fat content is related to CCK type-A receptor gene promoter polymorphism

The transcriptional start site of the human cholecystokinin (CCK)‐A receptor gene was determined by the Capsite Hunting method. Two sequence changes were detected, a G to T change in nucleotide −128, and an A to G change in nucleotide −81. The homozygote (T/T, G/G) was detected in 25 of 1296 individuals (1.9%) in the cohort study. This polymorphism showed a significantly higher percent body fat and higher levels of serum insulin and leptin, compared with wild type and heterozygotes. Our study provided the possibility that polymorphism in the promoter region of the CCK‐A receptor gene may be one of genetic factors affecting fat deposition.

Restricted diversification of T-cells in chronic active Epstein-Barr virus infection: Potential inclination to T-lymphoproliferative disease

To assess the abnormal T‐cell expansion in chronic active Epstein‐Barr virus infection (CAEBV), T‐cell antigen receptor (TCR) repertoire was analyzed in four patients with the disease. All fulfilled the diagnostic criteria of CAEBV, presenting with fever, hepatosplenomegaly, cytopenia, abnormal high titers of anti EBV‐antibodies, and positive EBV genome of unknown cause. Southern blotting probed with EBV‐terminal repeats and TCR Cβ gene indicated clonal expansion of the infected cells in 3 and 2 patients, respectively. The number of CD4+ HLA‐DR+ cells appreciably increased in patients 1 (59%) and 2 (24%), who had a coronary aneurysm and central nervous system involvement, respectively. TCR gene expression examined by the inverse polymerase chain reaction methods revealed that Vβ gene usages were preferential in all patients (Vβ7 and Vβ12: patient 1, Vβ4: patient 2, Vβ13: patients 3 and 4), compared with those in healthy controls. Vα18 gene expression was remarkably high in patients 1 and 2. Moreover, Jβ gene expression was skewing in the reigning Vβ clones in all patients. Vβ4‐Jβ1.5 and Vβ13‐Jβ1.5 genes were clonally expressed in patients 2 and 4, respectively. These results suggest that CAEBV is associated with the restricted diversity of T‐cells, which may stem from the sustained expansion of oligoclonal T‐cells possibly driven by conventional viral antigens, but not, superantigens. Although the study is limited by the small number of patients, the unbalanced T‐cell repertoire might contribute to the evolution of T‐lymphoproliferative disease, otherwise, imply the innate defective immunity to EBV in CAEBV patients. Am. J. Hematol. 61:26–33, 1999.

Primary central nervous system lymphomas. Immunophenotypic, virologic, and cytogenetic findings of three patients without immune defects

Background. Primary central nervous system (PCNS) lymphoma is a relatively rare disease, but an increasing incidence is reported. The Epstein‐Barr virus (EBV), which is often found in lymphomas of immuno‐compromised patients, has been implicated in the development of lymphomas. Many cytogenetic analyses of nodal B cell lymphomas have been performed, but few studies on PCNS lymphomas have been reported.

Clonal Analysis of Multiple Point Mutations in the N-ras Gene in Patients with Acute Myeloid Leukemia

We have screened mutations of the N‐ras gene at codons 12, 13, and 61 in leukemia cells obtained from 100 patients with acute myeloid leukemia (AMD, and found mutated N‐ras alleles in 9 patients. We further analyzed the polyclonality of multiple N‐ras gene mutations in 4 AML patients. One patient, who had the monoclonal karyotype, t(11;17), had two types of double missense mutations at codons 13 and 61 in the same allele. Each of the remaining three patients, one of whom had t(15;17) with a monoclonal rearrangement of the retinoic acid receptor alpha and PML genes, carried two missense mutations in a relatively small population of leukemia cells. We have demonstrated that multiple clonality of the N‐ras gene is occasionally observed in leukemia with a monoclonal karyotype. These findings indicate that the N‐ras mutations may not always be characterized simply by an accumulative process and that the activated N‐ras gene alone is not sufficient to cause leukemia.

9q34.3 deletion syndrome in three unrelated children

We described three unrelated children with cryptic 9q34.3 rearrangements and similar clinical manifestations: two with 9q34.3 terminal deletions and the other with an unbalanced translocation involving 9q34.3‐qter monosomy and 6p25‐pter trisomy. Common features among the three we studied and the other six patients with 9q34.3 deletions in the literature include microcephaly, mental retardation (MR), hypotonic, and epileptic seizures. Their facial characteristics included flat face, arched eyebrows, synophrys, hypertelorism, short nose, anteverted nostrils, carp mouth, protruding tongue, micrognathia, and pointed chin. Other frequent abnormalities were cardiac abnormalities, cryptorchidism or hypospadias, and abnormal toes. These findings are characteristic enough to be a clinically recognizable syndrome.

Microdeletion in the SHOX 3′ region associated with skeletal phenotypes of Langer mesomelic dysplasia in a 45,X/46,X,r(X) infant and Leri–Weill dyschondrosteosis in her 46,XX mother: Implication for the SHOX enhancer

It is known that SHOX nullizygosity results in Langer mesomelic dysplasia (LMD) and SHOX haploinsufficiency leads to Leri–Weill dyschondrosteosis (LWDC). Here, we report on a microdeletion in the SHOX 3′ region identified in a Japanese infant with LMD‐compatible skeletal features and a 45,X[191]/46,X,r(X)(p22.3q24)[9] karyotype and in her mother with LWDC‐compatible skeletal features and a normal 46,XX karyotype. Physical and auxological examinations revealed mesomelic appearance, ulnarly deviated hands, and borderline micrognathia in the infant, and relatively short forearms and lower legs in the mother. Radiological studies indicated mesomelia, markedly curved radii, hypoplastic ulnas and fibulas, and metaphyseal splaying in the infant, and borderline to mild curvature of the radii, decreased carpal angles, and high‐normal triangularization index in the mother. Cytogenetic and molecular studies showed that the ring X chromosome of the infant was missing SHOX and of paternal origin, whereas the cytogenetically normal X chromosomes of the infant and one of the two X chromosomes of the mother, though they retained SHOX with normal coding sequences, had a microdeletion in the SHOX 3′ region. The microdeletion started from a position ∼200 kb from SHOX coding sequences, and spanned 240–350 kb in physical length involving DXYS233. The results, in conjunction with those reported by Flanagan et al. [ 2002 ], suggest that a cis‐acting enhancer exists in the SHOX 3′ region around DXYS233.

Craniosynostosis with extra copy of MSX2 in a patient with partial 5q-trisomy

We describe a 2-year-old girl with craniosynostosis, atrial septal defect, patent ductus arteriosus, and trisomy for 5q34-qter, resulting from a maternal balanced translocation, t(5;13)(q33.3;q34). FISH analysis demonstrated three copies of the MSX2 gene. To our knowledge, the girl is the first documented case of craniosynostosis associatedwith an extra copy ofMSX2. Since the MSX2 expression is critical for the human skull development, its excess dose may have played an important role in the occurrence of craniosynostosis. Partial trisomy for 5q leads to a specific phenotype, i.e., growth and mental retardation, craniofacial abnormalities, cardiacmalformations, trunkand limbdefects, and craniosynostosis [Curry et al., 1979; Jones et al., 1979; Kumar et al., 1987; Elias-Jones et al., 1988; Van Der Burgt et al., 1992;Wysocka et al., 2002]. Amutation (P148H) in the homeodomain ofMSX2 that ismapped to 5q34-q35 has been reported in a family with autosomal dominant craniosynostosis,Boston type (OMIM604757) [Jabs et al., 1993]. The patient, a Japanese girl, was born at 36 weeks of gestation to healthy and nonconsanguineous parents. The mother had a miscarriage, a girl who died of craniosynostosis at age 7 months, and a phenotypically normal girl, other than the patient. Birth weight of the patient was 1,672 g ( 2.1 SD), length 43 cm ( 1.6 SD), and OFC 27 cm ( 2.8 SD). Craniofacial abnormalities, atrial septal defect, and patent ductus arteriosus were noted. Radiological examination showed craniosynostosis with early closure of the sagittal and lamboid sutures. Suboccipital craniectomywas performed at age 13 months. She steadied her head at age 10 months, rolled at 12 months, and sat unsupported at 18 months. At 28/12 years, her height was 72 cm ( 5 SD), weight 7.4 kg ( 3.5 SD), and OFC 41.5 cm ( 4.1 SD), and had oxycephaly, hypertelorism, thin upper lip, small mouth, high-arched palate and low-set, malformed ears (Fig. 1). G-banding chromosome analysis of cultured peripheral blood lymphocytes showed a normal karyotype in her father, 46,XX,t(5;13)(q33.3;q34) in her mother, and 46,XX, der(13)t(5;13)(q33.3;q34)mat in the patient. The karyotype of the girl was thus a product of adjacent-1 segregation of the maternal translocation and involved bothmonosomy for 13q34-qter and trisomy for 5q33.3-qter. FISH analysis on cultured lymphocytes from the patient, using BAC clone RP11-6O3017 covering MSX2 at 5q34-q35, LSI 13 (Vysis, Downers Grove, Illinois) containing RB1 at 13q14, and TelVysion 13q (Vysis) for the 13q telomere, showed three MSX2 signals, two 13q14 signals, and one 13q telomere signal, respectively (Fig. 2). These findings indicated that the patient had an extra copy of MSX2. Patients reported previously to have deletions involving 13q32 manifested microcephaly, brain and eye malformations, minor facial anomalies, growth and mental retardation, and cardiac, distal limb, and/or gastrointestinal tract malformations [Brown et al., 1993; Walsh et al., 2001], while those with more distal 13q33-q34 deletions were less severely affected, i.e., microcephaly, growth/mental retardation, minor facial anomalies [Stoll andAlembik, 1998;Luquet et al., 1999]. The clinical manifestations of the girl we described belong to the latter group, and are also consistent with those with partial trisomy for 5q [Curry et al., 1979; Jones et al., 1979; Kumar et al., 1987; Elias-Jones et al., 1988; Van Der Burgt et al., 1992; Wysocka et al., 2002]. Therefore, her clinical findings were explained by either partial 13q-deletion or partial 5q-trisomy, or both. All reported cases of craniosynostosis-associated 5qtrisomy involved 5q34-q35 where MSX2 is located [Kumar et al., 1987; Elias-Jones et al., 1988; Van Der Burgt et al., 1992; Wysocka et al., 2002], although those with such partial trisomy did not always have craniosynostosis [Curry et al., 1979; Jones et al., 1979; Rodewald et al., 1980; Abuelo et al., 2000; Martin et al., 2003]. A P148H mutation in MSX2 is responsible for autosomal dominant craniosynostosis,Boston type (OMIM604757) [Jabs et al., 1993], and enhances the DNA binding properties of the gene [Ma et al., 1996]. Loss-of-function mutations including deletions ofMSX2were reported in three unrelated families with enlarged parietal foramina (OMIM 168500), an oval defect of the parietal bones caused by deficient ossification around the parietal notch [Wilkie et al., 2000]. Satokata et al. [2000] showed that Msx2 deficient mice had defects of *Correspondence to: Dr. Takashi Shiihara, Department of Pediatrics, Yamagata University School of Medicine, 2-2-2 Iidanishi, Yamagata, 990-9585, Japan. E-mail: shiihara@med.id.yamagata-u.ac.jp

Non-multiple lymphomatous polyposis form of mantle cell lymphoma in the gastrointestinal tract.

Mantle cell lymphoma (MCL) comprises 2.5%–7% of all non-Hodgkin’s lymphomas, and the gastrointestinal tract is involved in about 20% of cases. Multiple lymphomatous polyposis (MLP) is an uncommon disease that is regarded as the intestinal form of MCL. We present a rare case of gastrointestinal MCL without MLP, and demonstrate that rituximab was effective for the treatment of this patient. A 61-year-old man presented with continuous diarrhea and hematochezia for a period of 5 months. Superficial lymph nodes were not palpable, but both tonsilla were enlarged. The level of soluble interleukin (IL)2-receptor was 3480 U/ml (normal <500 U/ml). Colonoscopy showed diffuse redness with erosion, without observation of any venous capillary, with these findings continuing from the rectum to the ileum. Upper gastrointestinal endoscopy showed a slightly rough gastric mucosal surface, and chicken-skin like mucosa was observed in the second portion of the duodenum. Small-to-medium size lymphoma cells were seen histologically from the tonsilla to the rectum. The lymphoma cells were immunohistochemically positive for CD5, CD20, CD79a, and cyclin D1. Polymerase chain reaction analysis revealed a chromosomal translocation t(11;14)(q13;q32) in the bcl-1 gene. We diagnosed this as a case of MCL from these findings. For treatment, the patient received a total of ten courses of combination chemotherapy consisting of cyclophosphamide (1000 mg), doxorubicin (70 mg), vincristine (2 mg) and prednisolone (50 mg) (CHOP), which led to a partial remission. However, 2.5 years later, massive infiltrations of the lymphoma cells were found in the colon and stomach. As the infiltrating lymphoma cells expressed CD20 molecules on their surfaces, the patient was treated with a chimeric anti-CD20 monoclohal antibody, rituximab, which showed significant efficacy, and a second partial remission was achieved.