A congenital mutation of the novel gene LRRC8 causes agammaglobulinemia in humans

A girl with congenital agammaglobulinemia and minor facial anomalies lacked B cells in peripheral blood: karyotypic analysis of white blood cells showed balanced translocation, t(9;20)(q33.2;q12). In the current study, we isolated a novel gene, leucine-rich repeat-containing 8 (LRRC8), at the translocation site on chromosome 9. It has four transmembrane helices with one isolated and eight sequentially located leucine-rich repeats (LRRs) and constitutes a new protein family. It is expressed on T cells as well as on B-lineage cells. Translocation truncates the LRRC8 gene, resulting in deletion of the eighth, ninth, and half of the seventh LRR domains located close to the C-terminal. The truncated form of the LRRC8 gene is transcribed with sequences from the noncoding region adjacent to the truncated seventh LRR. Protein products derived from the truncated gene are coexpressed on white blood cells with the intact LRRC8 protein from the untranslocated allele. Transplantation experiments with murine bone marrow cells that were forced to express the truncated LRRC8 show that expression of the truncated protein inhibited B cell development. These results indicate that LRRC8 is responsible for the B cell deficiency in this patient and is required for B cell development.     

Evidence by spectral karyotyping that 8q11.2 is nonrandomly involved in lipoblastoma

We report two cases of lipoblastoma with chromosome 8-related aberrations, ie, a 92,XXYY,t(7;8)(p22;q11.2)x2 [8]/46,XY[16] in Case 1 and a 46,XY,−8,−13,add(16)(q22),+mar, +r [cp13]/46,XY[7] in Case 2. Using spectral karyotyping and fluorescence in situ hybridization techniques, the karyotype of Case 2 was redesignated as 46,XY, r(8), del(13)(q12), der(16)ins(16;8)(q22;q24q11.2)[cp13]/46,XY[7]. This report delineates a new chromosome rearrangement, ie, der(16)ins(16;8)(q22;q24q11.2) in lipoblastoma, and also confirms the t(7;8)(p22;q11.2), reported only once previously, as a recurrent translocation involved in such a tumor. These findings provide valuable information for clinical molecular cytogenetic diagnosis of lipoblastoma. Furthermore, this report highlights the value of cytogenetic and molecular cytogenetic analysis in differential diagnosis of childhood adipose tissue tumors and adds to the number of lipoblastomas reported with chromosomal abnormalities at 8q11.2.     

二例M2型急性髓系白血病染色体t(8;19)(q22;q13)

目的　首次报道 2例M2 型急性髓系白血病 (AML M2 )有染色体t(8;1 9) (q2 2 ;q1 3 )。方法　应用骨髓细胞短期培养法制备染色体标本 ,并应用R和G显带技术进行核型分析 ;例 2 ,应用流式细胞仪和一组单克隆抗体检测其白血病细胞的免疫表型 ,应用筑巢式逆转录 聚合酶链反应 (RT PCR)技术检测其AML1/ETO融合基因转录本。结果　例 1的核型为 4 6,XX ,t(8;1 9) (q2 2 ;q1 3 ) [2 8] / 4 6,XX[2 ] ,例 2的核型为t(8;1 9) (q2 2 ;q1 3 ) ,del(9) (q1 2q2 2 ) [2 3 ] / 4 6,XY[2 ] ;例 2的白血病细胞表达CD13(3 8 8% )、CD33(3 1 8% )、CD34 (80 .9% )和CD19(63 .9% ) ,其AML1/ETO融合基因转录本为阴性。结论　t(8;1 9) (q2 2 ;q1 3 )是t(8;2 1 )的简单变异型 ,其分子学本质有待于进一步研究阐明。     

伴有t（8;21）染色体异常急性髓系白血病的免疫表型特征

本研究主要探讨具有t（8;21）（q22;q22）染色体改变的急性髓系白血病（acute myeloid leukemia,AML）患者的免疫表型及伴随的染色体异常。利用多参数流式细胞仪（multiparameter flow cytometry,MPFC）检测和分析47例具有t（8;21）的AML患者白血病细胞免疫表型。结果表明：47例t（8;21）-AML中21例（44.68%）伴有其他染色体异常,26例（55.32%）为单纯t（8;21）染色体改变。多参数流式检测结果提示：t（8;21）-AML患者干/祖细胞标记CD34、CD117和HLA-DR阳性率分别为87.2%、97.9%和95.7%,髓系标记CD13和CD33阳性率分别为93.6%和87.2%,T淋巴系标记CD2、CD3、CD5和CD7未见表达,B淋巴系标记CD19阳性率为66.0%,显著高于其他B淋巴系标记CD20和CD22,同时NK细胞标记CD56阳性率亦高达66.7%。结论：利用多参数流式细胞术检测t（8;21）-AML发现该亚型AML具有较为特异性的免疫表型特征：干祖细胞标志（CD34、CD117和HLA-DR）表达较高,并且B淋系标志CD19和NK细胞标志CD56表达明显较高,提示联合CD34/CD19/CD56检测可以成为预测AML可能具有t（8;21）（q22;q22）的染色体改变准确而快速的临床指标。     

8号染色体四体、三体共存的t(15;17)(q22;q12)急性早幼粒细胞白血病

本研究报道首例伴有8号染色体四体(四体8)、8号染色体三体(三体8)异常的t(15；17)急性早幼粒白血病(AML-M3a)，并探讨其形态学、细胞遗传学、分子生物学、免疫学及临床特点。用外周血及骨髓标本直接涂片观察形态学改变；采用骨髓细胞24小时短期培养法制备染色体标本，RHG显带技术进行核型分析；以筑巢式逆转录聚合酶链反应(nested RT—PCR)技术检测PML-RARa融合基因转录本；以间期荧光原位杂交(fluorescence in situ hybridization，FISH)技术检测8号染色体数目异常；以流式细胞术检测免疫表型。结果表明：外周血涂片早幼粒细胞占65％，可见中晚幼粒细胞。骨髓涂片显示有核细胞增生明显活跃，粒系83．6％，其中早幼粒细胞占72．4％，胞浆内可见大量紫红色颗粒。染色体核型分析揭示核型为48，XY， 8， 8，t(15；17)(q22；q12)[16]／47，XY， 8，t(15；17)(q22；q12)[3]／46，XY，t(15；17)(q22；q12)[1]。RT—PCR检测PML-RARa( )。FISH检测显示具有1，2，3，4，5，6个绿色荧光信号细胞的百分比分别为0．5，7，19，55，18和0．5。这不但证实了三体8和四体8克隆的存在．还发现存在一个较小的五体8克隆。白血病细胞免疫表型检测显示CD13(96．2％)、CD33(55．9％)、CYMPO(93．5％)阳性，其余抗原包括淋系抗原在内均为阴性。患者生存期只有10天。结论 本例四体8是t(15；17)的继发性改变，可能是三体8克隆进展的结果。伴有四体8的t(15；17)AML-M3预后差。     

Inhibition of the activation of Hageman factor (factor XII) by complement subcomponent C1q.

Hageman factor (HF, Factor XII) is activated by glass, collagen, and ellagic acid, and initiates blood coagulation via the intrinsic pathway. C1q inhibits collagen-induced platelet aggregation and adherence of platelets to glass, effects attributable to the collagen-like region of C1q. We examined the actions of C1q on HF activation. Incubation of C1q with HF before addition of HF-deficient plasma extended the activated partial thromboplastin time. Similarly, when glass tubes were coated with C1q before testing, the partial thromboplastin time of normal plasma was increased. C1q reduced the activation of HF by ellagic acid, as measured by the release of p-nitroaniline from the synthetic substrate H-D-prolyl-L-phenylalanyl-L-arginine-p-nitroanilide dihydrochloride, an effect inhibited by monoclonal anti-human C1q murine IgG and by digestion of C1q by collagenase. Thus, C1q inhibits activation of HF in vitro in clot-promoting and amidolytic assays and suggests a regulatory mechanism for the inhibition of coagulation.     

Genomic characterization of chromosome 8 pericentric trisomy

We present a patient with trisomy 8p11.21q11.21 associated with language, gross motor, fine motor, and cognitive delay. Furthermore, using array‐based comparative genomic hybridization, we identify the specific genes duplicated in our patient.     

20例t(8;21)复杂变异易位急性髓系白血病患者的临床和实验室研究

本研究总结分析t(8;21)复杂变异易位急性髓系白血病(AML)的形态学、免疫学、遗传学、分子生物学(MICM)分型,酪氨酸激酶相关基因突变和临床特点。对我院收治的20例初诊t(8;21)复杂变异易位AML进行了总结分析和随访,了解临床一般情况、形态学、免疫分型、染色体核型及治疗、生存情况,分析这一类疾病的基本特征。采用基因组DNA聚合酶链反应后桑格测序,对13例患者进行了酪氨酸激酶相关基因突变(C-KIT、FLT3-ITD、FLT3-TKD、JAK2V617F)的检测。结果表明:①本组20例t(8;21)复杂变异易位AML占同期t(8;21)AML的2.4%,其中M1 1例、M2 17例、M4 2例。13例行流式细胞术检测分析发现,10例为髓系表达,3例为髓系伴淋系表达。细胞遗传学检测显示额外受累的染色体断裂位点有16种:(lp22、1p32、2q35、2q14、3p25、5q13、6p22、7q21、llq11、1lql3、12q14、12q24、12p12、14q32、15p13、20q12)。②13例患者中4例检测出C-KIT基因突变,且均为17号外显子突变,1例检测出JAK2V617F基因突变,13例均未检测出FLT3基因突变。突变组患者经1个疗程诱导化疗后仅1例获得完全缓解(CR),CR率为20%,中位无复发生存时间(RFS)为6.5个月,中位总生存期(OS)为8.9个月;未突变组患者经1个疗程诱导化疗后6例获得CR,CR率为75%,中位RFS为26.6个月,中位OS为27.7个月。结论:t(8;21)复杂变异易位AML与典型t(8;21)AML的临床和实验室特点是相似的,但酪氨酸激酶相关基因突变的存在对患者的诱导化疗缓解率和长期生存具有重要的影响。     

含大剂量阿糖胞苷方案强化治疗伴t(8;21)和正常核型急性髓系白血病M2患者疗效比较

目的 比较伴t(8;21)和正常核型的急性髓系白血病(AML)M2患者在诱导缓解后,应用含大剂量阿糖胞苷(HD-Ara-C)方案进行强化巩固治疗的疗效.方法 伴t(8;21)(q22;q22)AML-M2患者21例,正常核型AML-M2患者23例,在诱导缓解后,给予4个疗程HD-Ara-C方案强化治疗:Ara-C 3.0 g/m2,每12 h 1次,静脉滴注持续3 h,第1～3天,同时交替联合使用其他药物(米托蒽醌7mg·m-2·d-1第1～3天或阿克拉霉素30 mg·m-2·d-1第1～3天或依托泊甙70 mg·m-2·d-1第1～3天等).结果 伴t(8;21)患者组复发率29%,3年总体生存(OS)率76%,3年无病生存(DFS)率71%;正常核型组复发率57%,3年OS率65%,3年DFS率43%.两组患者复发率及3年DFS率差异有统计学意义(P《0.05),3年OS率差异无统计学意义(P＞0.05).结论 伴t(8;21)AML-M2患者诱导缓解后,应用4个疗程含HD-Ara-C方案进行强化巩固治疗,复发率低,可以提高DFS率.     

Prognosis and treatment outcome in patients with acute myeloid Leukemia with t(8;21)(q22;q22)

Patients with acute myeloid leukemia (AML) with the t(8;21) karyotype generally have a favorable clinical course, but key prognostic factors remain poorly defined. This study was conducted to determine the prognoses and treatment outcomes of patients with AML with this unique cytogenetic change. A total of 22 patients with AML with t(8;21)(q22;q22) were studied. Various parameters were tested for their impact on disease-free survival (DFS) and overall survival (OS). Another 55 patients with AML with a normal karyotype were included for comparison of clinical outcomes. Between patients with t(8;21) and those with a normal karyotype, no significant differences were noted in DFS (median survival, 15.23 vs 12.03 mo;P=.7626) and OS (median survival, 19.17 vs 18.93 mo;P=.7543). Among t(8;21)(q22;q22) patients, no clinical parameters showed a significant impact on DFS. Univariate analysis revealed that a higher platelet count (> 15·10⁹/L) at diagnosis, a low white blood cell count (index ≤20), and hematopoietic stem cell transplantation (HSCT) as postremission therapy were associated with improved OS. On multivariate analysis, HSCT as postremission therapy and white blood cell count index < 20 remained good independent prognostic factors for OS. The data presented here suggest that t(8;21)(q22;q22) cytogenetic changes in patients with AML had prognostic significance similar to that in patients with a normal karyotype; patients who harbored either karyotype had parallel clinical outcomes. It is concluded that patients with AML with t(8;21)(q22;q22) would be compromised by treatment approaches that do not include HSCT as postremission therapy.     

Bactericidal activity of low-dose clindamycin administered at 8- and 12-hour intervals against Staphylococcus aureus, Streptococcus pneumoniae, and Bacteroides fragilis.

Twelve volunteers received 300 mg of clindamycin intravenously (i.v.) or orally (p.o.) administered every 8 h (q8h) or q12h by random assignment over four study periods. Serum bactericidal titers were determined for each regimen against two isolates each of Staphylococcus aureus, Streptococcus pneumoniae (one penicillin-sensitive isolate and one penicillin-resistant isolate), and Bacteroides fragilis. The duration of measurable bactericidal activity over the dosing interval (expressed as a percentage of the dosing interval) was determined for each isolate. No significant differences in the duration of activity were observed between i.v. and p.o. regimens dosed according to the same interval (P > 0.05). All regimens provided bactericidal activity against S. pneumoniae for 100% of their respective dosing intervals. Against B. fragilis, bactericidal activity was observed for greater than 80% of the dosing interval for each of the regimens. Although a statistically significant difference favoring the q8h i.v. regimen (P < 0.05) was detected, this difference is not believed to be clinically significant. The q8h and q12h regimens provided measurable bactericidal activity against S. aureus for greater than 85 and 50% of the dosing intervals, respectively (P < 0.001). Clindamycin dosed at 300 mg i.v. or p.o., q8h or q12h, provides adequate coverage against S. aureus, S. pneumoniae, and B. fragilis.     

两例急性髓系白血病伴t(6;21;8)(p22;q22;q22)复杂易位患者的临床与实验室研究

目的探讨2例急性髓系白血病（AML）伴t（6;21;8）（p22;q22;q22）复杂易位患者的临床及实验室特点.方法骨髓细胞经短期24 h培养后按常规方法制备染色体标本,R显带进行核型分析;双色双融合AML1/ETO探针进行丝裂间期及中期荧光原位杂交（FISH）检测AML1/ETO融合信号;逆转录-聚合酶链反应（RT-PCR）检测AML1/ETO融合基因转录本;综合分析临床特征.结果2例患者常规细胞遗传学分析显示均存在t（6;21;8）（p22;q22;q22）,间期和中期FISH证实了核型结果;RT-PCR检测到AML1/ETO融合基因转录本;尽管2例患者均诊断为AML-M2,但二者的免疫表型和治疗反应不同.结论t（6;21;8）（p22;q22;q22）是一种少见的t（8;21）（q22;q22）的复杂变异易位,还需要更多的病例以明确其临床特征和预后价值.     

急性髓系白血病伴t（8;21）的临床特点及预后

目的探讨t（8;21）急性髓系白血病（acute myeloid leukemia,AML）的临床特点及预后,提高对t（8;21）AML的认识。方法 2010年5月收治1例t（8;21）AML患者,对其临床资料并复习相关文献进行分析。患者因乏力、皮下瘀斑入院,查体发现患者有胸骨压痛,脾肋下3cm触及,血常规：白细胞80.37×10^9/L,异常细胞23%,取患者骨髓液行形态学、流式细胞术检测及染色体核型检测。结果患者诊断为急性粒细胞白血病部分分化型（AML-M2b）,AML1/ETO融合基因阳性,染色体核型分析t（8;21）（q22;q22）。结论 t（8;21）AML是一类较为特殊的急性髓系白血病,在诊断时需寻找疾病的预后因素并进行分层,实施个体化治疗。     

Duplication of 19q (13.2-13.31) associated with comitant esotropia: A case report

BACKGROUNDComitant esotropia is the most common form of strabismus. It is caused by heterogeneous environmental and genetic risk factors. The pure duplication of the long arm of chromosome 19 is a rare abnormality. Only 8 patients with partial trisomy of the long arm of chromosome 19q have been reported to date. Here, we describe a girl with pure duplication of 19q, who was diagnosed with congenital esotropia, microcephaly, and gallbladder agenesis. CASE SUMMARYThe patient was diagnosed with esotropia when she was 1-year-old. The Krimsky method showed +50 prism diopters in the primary gaze position. No additional abnormal findings were observed following slit lamp and fundus examination, but the features of the full-field electroretinogram showed a decreased amplitude and increased implicit times. Magnetic resonance imaging showed ventriculomegaly with thinning of the corpus callosum and splenium in her brain. A 4.42 Mb mosaic duplication within 19q13.2-q13.31 region (chr19:39,343,725 to 43,762,586) was detected by microarray comparative genomic hybridization. CONCLUSIONStrabismus is reported in many live borns with pure duplication of 19q. This important clinical characteristic indicates that the candidate genes fundamental for this phenotype may be narrowed to genes within the 19q13.3-q13.31 region. There were two candidate genes observed that may contribute to the comitant esotropia phenotype, namely XRCC1 (19:43,543,311) and SMG9 (19:43,727,991).     

CD5-negative blastoid variant mantle cell lymphoma with complex CCND1/IGH and MYC aberrations

The coexistence of CCND1/IGH and MYC rearrangements in mantle cell lymphoma (MCL) is a rare finding associated with a very poor prognosis. In this study, a patient with blastoid variant (MCL) is reported. The disease was clinically aggressive and refractory to chemotherapy, and the patient only survived for 1 month following diagnosis. Conventional cytogenetic study, FISH, and multicolor FISH (mFISH) demonstrated the involvement of the BCL1/CCND1 locus in a complex translocation, t(3;11)(q25;p15)t(11;14)(q13;q32). In addition, subclonal abnormalities in the 8q24 region, manifested as a t(8;14)(q24;q32)/MYC rearrangement, were identified. To the best of our knowledge, this is the first MCL case in Korea bearing these complex genomic aberrations.     

A multicenter, double-blind, randomized comparison of oral ondansetron 8 mg b.i.d., 24 mg q.d., and 32 mg q.d. in the prevention of nausea and vomiting associated with highly emetogenic chemotherapy

The objectives of this study were to compare the efficacy and safety of orally administered ondansetron 8 mg b.i.d., 24 mg q.d., and 32 mg q.d. in the prevention of nausea and vomiting associated with high-dose cisplatin-based chemotherapy (cisplatin > or = 50 mg/m2). This was a randomized, parallel-group, double-blind study conducted in North America. It was planned that all patients would receive one of the following orally administered ondansetron treatments 30 min before starting cisplatin dosing (administered over < or = 3 h): 8 mg b.i.d. with 8 h between doses (124 patients), 24 mg q.d. (116 patients), and 32 mg q.d. (117 patients). Use of prophylactic corticosteroids was not permitted. During the 24-h study period, the highest complete response rate (no emesis, rescue antiemetic therapy, or withdrawal) occurred in patients who received ondansetron 24 mg q.d.: 76/115 or 66%, as against 68/124 (55%) after ondansetron 8 mg b.i.d. and 64/117 (55%) after ondansetron 32 mg q.d. Complete control of nausea (no nausea, no rescue, no withdrawal) occurred in more patients in the ondansetron 24 mg q.d. group (64/114, 56%) than in the ondansetron 8 mg b.i.d. group (43/121, 36%) or in the ondansetron 32 mg group (55/117, 50%). These results demonstrate that following highly emetogenic cisplatin-based chemotherapy (> or =2 50 mg/m2), oral ondansetron 24 mg q.d. is more effective than 8 mg b.i.d. for overall control of nausea, and at least as effective if not more effective in the control of acute vomiting than 8 mg b.i.d. or 32 mg q.d. Ondansetron 24 mg q.d. was well tolerated, and no new or unexpected adverse events were identified.     

t（8;21）急性髓系白血病发病机制的研究进展

近50%的急性髓系白血病可以找到染色体易位,常见的染色体易位是t（8;21）（q22;q22）。这种易位使21号染色体上的aml1（runx1）基因与8号染色体上的eto（mtg8,runx1t1）基因相互融合形成aml1/eto融合基因。最初对于t（8;21）急性髓系白血病发病机制的研究一直着重在造血转录激活因子AML1转化为白血病抑制因子,在靶基因调控水平上阻碍髓系细胞分化,aml1/eto融合基因在造血分化过程关键点抑制作为肿瘤抑制因子的造血转录因子。目前认为,t（8;21）染色体易位及二次突变引起造血干细胞减少的系别限制性及基因组不稳定性是引发aml1/eto融合基因阳性白血病的主要原因。本文就aml1/eto融合基因及其剪接变异体在调控干细胞更新、阻断造血分化及与各造血系统特异的转录因子相互作用的分子机制进行综述。     

Molecular cytogenetic characterization of esophageal cancer detected by comparative genomic hybridization

Aim: Detection of cytogenetic alterations in esophageal cancer (EC). A total of 40 cases of primary EC and their paired nearby nontumor tissues were collected. The comparative genomic hybridization (CGH) is the technique that brings out the gains and losses of chromosome fragments and was applied to determine the aberrations from the tissue DNA. In noncancer tissues, the gains were at 19p (5/40, 13%), 20q (5/40, 13%), and losses at 9p (13/40, 33%), 2q (10/40, 25%), 12q (10/40, 25%), 13q (10/40, 25%), 5q (9/40, 23%), 6q (9/40, 23%), 7q (9/40, 23%), and 8p (9/40, 23%). Two cases in nontumor tissues showed no CGH change. In the 40 cases of primary EC, the gains were at 8q (10/40, 25%), 3q (9/40, 23%), 2q (7/40, 18%), and 13q (7/40, 18%), and the losses were at 1q (8/40, 20%), 4q (8/40, 20%), 3p (7/40, 18%), 5q (7/40, 18%), and 18q (7/40, 18%) in comparison with paired nearby noncancerous tissues. We found that the loss aberrations were on 1q, 2p, 3p, 5q, 6q, 9p, 11p, 15q, 16q, 18q, 21q and gains on 20p in both tumor and nontumor tissues; nevertheless, ?4p, ?7q, ?8p, ?10q, ?12q, ?13q, ?14q and +17p, +19q, +22q were only found in nontumor tissues and +1q, +2pq, +3q, ?4q, +4q, +5q, 7p, +8q, +10q, +12q, +13q, +14q ?17p, ?19pq, ?22q in EC. From these results, we suggest that most of the tissues near the cancer parts of EC may be considered as a precancerous region. The alteration between cancer and noncancer tissues may play a role in the development of EC. J. Clin. Lab. Anal. 24:167–174, 2010.© 2010 Wiley‐Liss, Inc.