多数の濾胞性リンパ腫（欧米において約90%, 本邦において約30%の濾胞性リンパ腫）の腫瘍細胞はt(14;18)染色体転座を有しており，この転座のために第14番染色体上にある免疫グロブリンH鎖(IgH)と第18番染色体上にある-2遺伝子が融合遺伝子を形成していることが判明している。-2遺伝子側における染色体切断部位は，ほとんどの例がhot spotすなわち第2エクソン内(mbr)もしくは遺伝子3'下流(mcr)の2箇所に集中している。これに対し約10%のB細胞慢性リンパ性白血病(B-CLL)においては，遺伝子5'上流部位で切断された-2遺伝子が，head to headに免疫グロブリンL鎖(Igλ, Igκ)と連結していることを見いだした。こうしたことは，濾胞性リンパ腫とB-CLLにおける-2遺伝子の活性化機序の相違を予想させ興味深い。

抄録全体を表示

症例は74歳男性。高度腎機能障害と高K血症のため救急搬送され，PET/CT検査にて左腎門部から膀胱まで連続した腫瘍性病変，多発リンパ節腫脹および多発骨病変を認めた。骨髄生検にて，B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphomaと診断された。FISH法にてMYC, IgH-2, 6転座を認め，triple-hit lymphoma (THL)と診断した。Dose-adjusted (DA)-EPOCH-R療法を8コース施行し部分寛解が得られた。MYC転座を含む複数の転座を有するdouble-hit lymphoma (DHL)/THLは極めて予後不良な疾患である。DA-EPOCH-R療法は本疾患に対する有効な治療選択肢になると考えられた。

抄録全体を表示

目的 : 細胞診標本において濾胞性リンパ腫 (follicular lymphoma Grade 1-2, FL G1-2) の腫瘍細胞は, 非腫瘍性病変との鑑別に苦慮する場合がある. そこで今回われわれは,

2 と 6 との二重免疫染色を考案し有用性を検討した.

方法 : 2000～2016 年の 16 年間に当院で手術され, 確定診断された悪性リンパ腫 35 例, 非腫瘍性病変 15 例, 計 50 例の細胞診標本を対象とし, 二重免疫染色を行った.

成績 : 二重に染まっている細胞を陽性と判断した結果, FL G1-2 は 8 例すべて, B 細胞性リンパ腫全体では 29 例中 22 例が陽性を示した. これに対し非腫瘍性病変は 15 例すべて陰性であった. T 細胞性リンパ腫, 古典的ホジキンリンパ腫は陰性を示した.

結論 :

2 および 6 を組み合わせた免疫染色は, FL G1-2 の診断において強力な補助診断ツールであることが示された.

抄録全体を表示

Using three chromosome 18-specific DNAs, rearrangements of a -2 gene were detected in 20 (44%) of 45 Japanese patients (pts) with follicular lymphoma (FL) and 3 (8%) of 36 pts with diffuse large cell lymphoma. The 21 pts had t(IgH; -2), and of the remaining two who did not display it, one had chromosome t(14;18). Compared with the findings in American pts, the lower frequency of t(14;18)-positive lymphoma could reflect a difference in the incidence of overall nodal B lymphoma between Japan and the United States. 11 of 18 pts with t(14;18)-positive FL expressed CD10 antigen on the cell surface and all 12 pts with t(14;18)-negative FL did not, and the difference is statistically significant, indicating that t(14;18)-positive Japanese FL is the same disease entity as most of American FL. Extra 18q- chromosome found in the advanced grade diseases of t(14;18)-positive lymphoma results in amplification of the rearranged -2 gene on 18q-, suggesting that the change is closely associated with transformation of FL carrying t(14;18). It is thus possible of international realization to institute the prognostic factors and the treatment strategy for conquerring t(14;18)-positive lymphoma.

抄録全体を表示

The sublimation rate of Xe from a -Xe solid mixture with low dilution at about 70K, is suppressed more than 30% by exciting the ν₃ vibration. A possible explanation for this phenomenon is presented. Larger volatility of Xe than that of causes the formation of a dense layer at the surface of the solid.To sublimate, Xe should diff Use through this layer. The diffusion of Xe in would probably be inhibited by the increase of vibrational amplitude of molecules. It is shown in terms of probabilities that the small increase of interaction cross section between Xe and can significantly decrease the Xe diffusivity in the layer.

抄録全体を表示

Both the rearrangement and the expression of the -2 gene in Japanese hematopoietic tumor cells were studied by Southern and Northern blot hybridizations. The expression of the -2 gene was studied in seven cultured cell lines and twenty clinical samples, including eleven non-lymphoid tumors and nine lymphoid tumors. All lymphoid tumors except one sample from a patient with ALL expressed the -2 gene. The -2 gene was strongly expressed in B cell tumors. This gene was also expressed in T-ALL samples studied, although the expression was not as marked as in the B cell tumors. Non-lymphoid tumors did not express -2 gene. -2 gene rearrangement was studied in five cultured cell lines and six clinical samples including four follicular lymphomas and two T-ALLs. No abnormal -2 gene configurations were found in any of the clinical samples. Among the cultured cell lines, the BALL-1 line showed two-fold amplification. The frequency of -2 rearrangement in Japanese follicular lymphomas is reported to be lower than that seen in the American follicular lymphomas. Nevertheless, the increased expression of the -2 gene seen in the Japanese B cell tumors studied supports the contention that the -2 gene plays an important role in the pathogenesis of B cell tumors.

抄録全体を表示

Oxidative stress affects all intracellular macromolecules, and leads cells to death under unfavorable conditions. Glutathione (GSH) is known to play a critical role in the cellular defense against unregulated oxidative stress in mammalian cells including neurons. We previously demonstrated that GSH depletion induces cell death in the retina, but the mechanism of cell defense by GSH is still unclear. Thus, we here examined the effect of GSH depletion on expression of members of B-cell CLL/lymphoma 2 (-2) family (-2,

bcl

-X_L, bax, bak, n-bak and bad) known to play key roles in determining cell viability. In order to deplete intracellular GSH, we systemically administrated buthionine sulphoximine (BSO), an inhibitor of γ-glutamylcysteine synthetase to mice. After 0, 1, 4, and 7 days of BSO injection, total RNAs from retina of each animals were isolated and subjected to real-time reverse transcription (RT)-polymerase chain reaction (PCR) analysis. Expression of

bcl

-X_L increased one day after BSO injection, but was back to the basal level on day 4. Its expression decreased on day 7. Expressions of -2 and bax were significantly decreased from 4 days after BSO injection, whereas expression of bad was not changed. An anti-apoptotic molecule, bak displayed a significant decrease 7 days after BSO injection, whereas neuronal cell specific Bak (-2 homologous antagonist/killer), N-Bak was not altered in its gene expression. Taken together, we demonstrated that decrease in intracellular glutathione level altered expressions of -2 family members in distinct manners. Our study implies a defensive mechanism of GSH against oxidative stress for retinal neuronal survival which may involve alteration of expression of -2 family members, especially -2 and -X_L. Thus, over-expression of -2 and -X_L may not the only but a critical factor in GSH-dependent cellular protection, and which implies -2 and -X_L may provide a potent therapeutic tool for cures against oxidative stress induced retinal degenerative diseases such as glaucoma, retinopathy, and age-related macular degeneration.

抄録全体を表示

原発性副腎リンパ腫は，非ホジキンリンパ腫の0.2％以下と稀な疾患であり，その多くがdiffuse large B-cell lymphoma（DLBCL）でintravascular large B-cell lymphoma（IVLBCL）は少ない。今回我々は，両側の副腎腫瘤で発症した75歳，男性のIVLBCLを経験した。全身状態不良のためCTガイド下で行った生検でIVLBCLと診断した。免疫染色ではCD20およびMUM1陽性，CD10陰性で，

2, 6, MYCのtriple expressionを認めた。骨髄生検でB-cell lymphomaの浸潤を認めたが血球貪食像は見られなかった。骨髄染色体検査で複雑核型を検出したがFISH法では2, MYCの転座は認めなかった。R-CHOP療法に反応を示したものの，経過中に中枢神経浸潤の出現を認めた。本例はnon-GCB subtypeの副腎腫瘤を伴ったIVLBCLであり予後は不良と推測される。本例のような2, 6, MYCのtriple expressionを示す副腎原発IVL症例の報告は少なく，治療反応性を含めた病態解明の点から症例の蓄積が必要と考えられる。

抄録全体を表示

t(14;18)(q32;q21)が認められるリンパ腫では，免疫グロブリン(Ig)遺伝子が-2遺伝子に近接することにより-2遺伝子が活性化されている。近接した両遺伝子は-2-Ig融合遺伝子を形成し，5'側が-2, 3'側がIgというキメラmRNAを形成するが，蛋白翻訳領域は変化せずに保たれる。活性化-2遺伝子を正常ヒトB細胞株に導入したところ，寒天内コロニー形成率は3+5倍に上昇したが，ヌードマウスに腫瘍は形成しなかった。本邦B細胞性リンパ腫における-2再構成を検索し，濾胞性リンパ腫32例中10例(31%), び慢性リンパ腫56例中5例(9%)に再構成を認めた。B細胞性リンパ腫，特に濾胞性リンパ腫発症頻度が米国に比較し本邦に少ないのは，-2再構成が少ないことが一因であることが示唆された。米国症例で報告の無い再構成様式を解析したところ，B細胞分化段階の進んだ時期に転座したことが示唆され，本邦において-2再構成が少ないのは，D_H-J_H結合時になんらかの原因で転座がおこりにくい機序が存在することによるのかも知れない。

抄録全体を表示

The -2 gene product has been reported to block apoptosis and to contribute to tumorigenecity. This study examined whether -2 expression was involved in the development of ameloblastoma. We carried out immunohistochemical studies of 20 cases of ameloblastoma using anti--2, anti-PCNA antibodies, and the TUNEL method to identify DNA fragmentation in situ. By immunohistochemical techniques, -2 expression was observed in all specimens except those that were decalcified.
Localization of -2 was found at nuclei and cell membranes of the peripheral layer. The TUNEL method showed positive reactions at epithelium with squamous metaplasia and a trend toward cornification. These results suggested that the -2 gene product might contribute to the development of ameloblastoma by the blocking apoptosis at the peripheral layer of the epithelial islets.

抄録全体を表示

It is known that the progression of dermal hemangioma is highly related with apoptosis of vascular endothelial cell. Researches more and more attached importance to study some apoptosis related factors on affacting the proliferation and involution of dermal hemangioma. The -2 family is a group of evolutionary conserved pro- and antiapoptotic proteins that play a pivotal role in the regulation of the mitochondrial-mediated apoptotic pathway. The expression of -2 family members in hemangioma is controversial. Some think that the expression of -2 in hemangioma is inherent and different. The other consider that skin hemangioma do not express -2. In order to illustrate the apoptotic mechanism of dermal hemangioma through the mitochondrail pathway, immunohistochemistry method and in situ hybridization were used to detect the expression of bax, -2,-xl and caspase9 mRNA in hemangioma, including proliferative hemangioma, involutional hemangioma and normal skin tissue. The expression of -2 and -xl in proliferating hemangioma were markedly stronger than that in involuting hemangioma (P‹0.01).On the contrary, the expression of bax and caspase9 mRNA in involuting hemangioma were significantly higher than that in proliferating hemangioma (P‹0.01, P‹0.05, respectively).There were no positive expression of these apoptotic related factors in normal skin tissue.

抄録全体を表示

11b is a lineage-specific transcription factor expressed in various cell types and its expression is important for development of T cells, neurons and others. On the other hand, 11b is a haploinsufficient tumor suppressor and loss of a allele provides susceptibility to mouse thymic lymphoma and human T-cell acute lymphoblastic leukemia. Although there are many transcription factors affecting both cell differentiation and cancer development, 11b has several unique properties. This review describes phenotypes given by loss of 11b and roles of 11b in cell proliferation, differentiation and apoptosis, taking tissue development and lymphomagenesis into consideration.

(Communicated by Shigekazu NAGATA, M.J.A.)

抄録全体を表示

It is well known that the anti-apoptotic protein -2 and its homologue -X_L are overexpressed in many human cancers and play a crucial role in cancer progression. Therefore, the functional blockade of -2/-X_L will be a promise for novel anticancer therapeutics by way of improving tumorigenesis. In the course of screening for an inhibitor of -X_L, anti-apoptotic function using human SCLC Ms-1 cells that overexpress -X_L, we found Incednine (1) in the fermentation broth of the strain Streptomyces sp. ML694-90F3. 1 was isolated as a HCl salt by using the Centrifugal liquid-liquid Partition Chromatography, effectively. The planar structure of 1, C_<42>H_<63>N_3O_8 ([M+H]^+, m/z 738.4680, Δ-1.3mmu), was elucidated on the basis of the various NMR spectra data including TOCSY experiments (Fig. 1). The relative stereochemistry of 1 was determined by the analysis of NOE experiments and coupling constants (Fig. 2). The conformation of the aglycon was confirmed by Discovery III-computations. The absolute stereochemistry of 1 was established by modified Mosher's method and X-ray crystallographic analysis (Fig. 3, 4). Incednine has a unique skeletal structure, "enol-ether amide" in the 24-membered macrolactum core, with an attachment of a disaccharide. -X_L-overexpressing Ms-1 cells displayed resistance to several anti-tumor agents, however, anti-tumor agents-induced cell death was observed only when cells were treated with 1. Overexpression of -X_L inhibited cell death in Bax-overexpressing HEK293T cells by forming a complex with -X_L and Bax, whereas it failed to inhibit cell death in the presence of 1 without affecting the formation of -X_L and Bax complex. The inhibitory mechanism of anti-apoptotic -X_L by 1 is now under investigation.

抄録全体を表示

To explore the metabolic effects of -2 in tumor cells, a stable clone of HuH-7/-2 and its control HuH-7/neo were established. Mitochondrial localization of ectopic -2 was demonstrated both by western blotting and immunofluorescence. HuH-7/-2 cells consumed glucose at a higher rate, exhausted the available cellular ATP and died on day 9, while HuH-7/neo cells were still alive for 10 days under the same condition where cells were cultured without replenishment of the medium. The expression of the hexokinase II gene was up-regulated in HuH-7/-2 at its protein level. Taken together, we suggest that the forced expression of -2 in human hepatoma may cause the cells to become more glucose-dependent for survival.

抄録全体を表示

The aim of this work was to examine factors that could be involved in the occurrence of apoptosis in rat hearts subjected to coronary occlusion followed by reperfusion. To this end, we studied the expression of the pro- and anti-apoptotic factors, bax and -2, respectively, in reperfused ischemic hearts and in hearts injected with bFGF or saline. In anesthetized rats the left coronary artery was occluded for 45 min, the anesthesia withdrawn and the occlusion removed to allow reperfusion; in sham-operated rats the occlusion was omitted. After 4 hours the rats were decapitated and the heart excised. Sections from the left ventricle were stained with anti--2-antibody and anti-bax-antibody using the TUNEL method which detects apoptosis. Fragmentation of DNA isolated from reperfused ventricles was examined by agarose electrophoresis. In reperfused hearts no -2 staining was observed in the discrete area in which many cardiomyocyte nuclei were stained by the TUNEL method; outside this area staining for -2 was more marked than in sham-operated rats. Sections from reperfused hearts were stained for bax protein over a wide area including the apoptotic region; sham-operated hearts showed little reaction. Staining for -2 was demonstrable in some nuclei in hearts from saline-injected rats; the numbers were unaffected by i. v. bFGF. Ischemia/reperfusion increases the overall expression of both -2 and bax proteins, but -2 is lost from the reperfused area as indicated by TUNEL staining. Accordingly, the ratio of -2 to bax was reduced in the reperfused area, indicating a pro-apoptotic trend. The marked increase in -2 outside the reperfused area could be a mechanism with which to salvage surviving cardiomyocytes.

抄録全体を表示

The molecular mechanisms regulating epidermal differentiation and apoptosis have not been elucidated. -2, one of the candidate genes for suppressing apoptosis, was originally cloned from the breakpoint of a t (14;18) translocation present in many human B cell lymphomas. In this study, the influence of -2 on apoptosis was observed in transfected keratinocytes. After transfection of pEF-BOS vector withlwithout -2, the expression of coded protein and the viability under starved conditions were examined. The -2-transfected keratinocytes had cytoplasmic positive staining with anti--2 monoclonal antibodies, however the vector only transfected cells were devoid of the reaction products. The viability of transfected keratinocytes under starved conditions, with a lack of epidermal growth factor and bovine pituitary extract, was maintained in -2 trans-fected cells; while the vector only transfected cells showed apoptotic cell death. The present result indicates that -2 suppresses apoptotic cell death under starved conditions due to a lack of epidermal growth factor and bovine pituitary extract.

抄録全体を表示

We describe two follicular lymphoma (FL) patients with MYC/

double- and MYC// triple-hit translocations. The first patient (case 1) was a man in his 30s who presented with stage IV disease with leukemic manifestation. The second patient (case 2) was a man in his 60s who presented with relapsed FL, but his disease was in a limited stage. Histopathology of the lymph node biopsies revealed grade 3A FL in both cases. MYC positivity and the Ki-67–labeling index were 60–70 and 20% in case 1 and 30 and 50% in case 2, respectively. G-banding revealed t(8;14;18)(q24;q32;q21) in both cases and fluorescence in situ hybridization using MYC, IGH, and break-apart probes confirmed t(8;14;18)(+5′2,−3′MYC;+3′MYC,−5′IGH;+5′IGH,−5′2). In case 2, additional materials of der(8)t(8;14;18) were duplicated and translocated to chromosome Y, and t(3;16)(q27;p13)/::CIITA was identified. We obtained -major breakpoint region::IGHJ5::IGHG1 and MYC exon 2::IGHA2 fusion sequences by long-distance polymerase chain reaction in case 1, and proposed that t(8;14;18) was generated by two-step translocations and that ::IGH and MYC::IGH involved the same IGH allele. Both patients responded to the standard chemotherapy for FL. We suggest that the presence of t(8;14;18) in FL does not immediately indicate high-grade transformation and aggressive clinical behavior requiring intensive chemotherapy.

抄録全体を表示

予防投与として, セフトリアキソン1gを点滴静注した際の, 抜歯後ならびに歯科観血処置後の菌血症の発現頻度をBactec NR 16 A, 17A (Becton Dickinson社, U.S.A.) を用いて検討した.20例中3例で菌陽性となり, その発現率は15%であった.検出菌3株は, いずれも嫌気性菌で, Streetococcusは1株も検出されなかった.3株に対するセフトリアキソンのMICは, 0.39, 1.56および12.5μg/ml, 同時に測定した血液培養施行時の血清中セフトリアキソン濃度は, 95～277μg/mlであった.セフトリアキソン1gの点滴予防投与により, 抜歯後の菌血症発現率は明らかに減少した.

抄録全体を表示