H-Y antigen expression in patients with X-autosomal translocations and gonadal dysgenesis

Cells from three patients with early gonadal failure and a balanced reciprocal translocation involving the long arm of the X chromosome and an autosome were studied. Fibroblasts from a patient with a similar balanced reciprocal translocation but normal reproductive capabilities were also studied. Two of the four patients were found to have serologically detectable H-Y antigen on their cells. Since H-Y antigen has been found on the cells of other patients with X chromosome abnormalities but without a Y chromosome, it is thought that the X chromosome plays a role in the regulation of H-Y antigen expression. This study suggests that the long arm of the X chromosome may be involved but the location of a regulatory gene cannot be identified in these studies. These cases do not permit us to implicate H-Y antigen as a cause of gonadal dysgenesis and early gonadal failure in females who have structurally abnormal X chromosomes.     

Autosome and Sex Chromosome Diversity Among the African Pygmy Mice, Subgenus Nannomys (Murinae; Mus)

The African pygmy mice, subgenus Nannomys, constitute the most speciose lineage of the genus Mus with 19 recognized species. Although morphologically very similar, they exhibit considerable chromosomal diversity which is here confirmed and extended by the G-banding analysis of 65 mice from West and South Africa. On the basis of their karyotype and distribution area, the specimens were assigned to at least five species. Extensive differentiation both within and between species was observed that involved almost exclusively Robertsonian translocations, 23 of which are newly described. Two of the rearrangements were sex chromosome-autosome translocations, associated in some cases with partial deletions of the X or Y chromosomes. Several authors have predicted that the highly deleterious effect of this rearrangement would be reduced if the sex and autosomal segments were insulated by a block of centromeric heterochromatin. The C-banding analyses performed showed that among the species carrying X-autosome translocations, one followed the expected pattern, while the other did not. In this case, functional isolation of the sex and autosome compartments must involve other repetitive sequences or genomic traits that require further molecular characterization. Such studies will provide insight into the causes and consequences of the high diversity of sex chromosome rearrangements in this subgenus.     

Case of acute lymphoblastic leukemia presenting with t(14;18)/BCL2, t(8;14)/cMYC, and t(1;2)/FCGR2B

The majority of follicular lymphoma and Burkitt's lymphoma are associated with reciprocal translocations involving BCL2 and cMYC, respectively. Unusual reports of aggressive lymphoma presenting with both translocations have been described as well as rare cases with a third structural alteration usually involving BCL6. The patient described here presented with aggressive high-grade lymphocytic leukemia, FAB subtype L2 (ALL-L2), and three reciprocal translocations, t(14;18)(q32;q21), t(8;14)(q24.1;q32), and t(1;2) (q22-23;p13). Despite immature morphology the leukemic blasts had a mature B-cell phenotype; they were positive for surface immunoglobulin heavy chains and negative for CD34, TdT, and CD10. Most reported dual t(14;18)/t(8;14) cases have not shown sIg and were positive for CD10. Molecular genetic analyses showed the typical rearrangements of BCL2 and cMYC as well as the FCGR2B gene on chromosome 1q23. The occurrence of a third oncogene rearrangement in association with the dual BCL2, cMYC translocations in ALL patients is very rare. To our knowledge, this is the first case where the third hit involves the FCGR2B locus. This report reiterates the poor prognosis associated with activation of cMYC together with elevated Bcl-2 expression. These data also support recent evidence that dysregulation of FCGR2B may play a role in tumor progression.     

儿童肾细胞癌3例临床病理分析

目的：探讨儿童肾细胞癌(renal cell carcinoma,RCC)的临床病理特征、分类、诊断与鉴别诊断。方法：收集2003年~至今湖南省儿童医院3例儿童RCC病例,其中男性2例,女性1例,年龄5.5~9岁。进行光镜及免疫组化检测重新分类。结果：1例镜下以乳头状结构排列胞浆透亮的癌细胞为主,乳头间可见纤维、血管及炎细胞浸润,伴有较多钙化小体结构;其余2例镜下均以实性巢索状、腺管状排布的嗜酸性颗粒癌细胞为主,灶性区域有少量透明癌细胞排列成不典型乳头状结构,未见钙化小体;免疫组化结果：其中1例表达TFE3、Vimentin、CK-pan和CEA;第2例表达Vimentin、CK-pan、CEA及p53;第3例表达Vimentin、CK-pan、CEA、NSE、CgA、Syn及Ki-67。结论：儿童RCC较少见,HE形态下以乳头状结构排列的透明癌细胞类型需结合TFE3免疫组织化学或基因检测等手段明确诊断。术前采用静脉化疗能提高肿瘤完整切术率。儿童RCC整体预后与成人相比较好,但Xp11.2易位/TFE3基因融合相关性肾癌(Xp11 RCC)预后较透明细胞性肾细胞癌(clear cell renal cell carcinoma,CCRCC)差,由于其在儿童期多表现为惰性进展,需长期的随访观察。     

Comparable outcomes between unrelated and related donors after reduced-intensity conditioning allogeneic hematopoietic stem cell transplantation in patients with high-risk multiple myeloma

The purpose of this study was to assess the results of allogeneic stem cell transplantation (allo-SCT) after reduced-intensity conditioning (RIC) from matched related donors (MRD) and unrelated donors (URD) in 40 patients with high-risk multiple myeloma (MM) in a single centre. Seventeen (43%) (Group 1) and 23 patients (57%) (Group 2) had URD and MRD, respectively. Thirty-nine patients (98%) received one or more autologous transplantation. The median follow-up was 22 months (1-49). None of our patient experienced a graft rejection. The cumulative incidence of grade II-IV acute GVHD was higher (47%) for the URD vs. (17%) for the MRD (P = 0.092). The cumulative incidence of chronic GVHD was no different between the two groups (24% vs. 30%, respectively). At 2 yr, the TRM probabilities were lower in the unrelated group 12% vs. 22% in the related group (P = 0.4). Also at 2 yrs, for patients receiving unrelated transplantation overall and progression-free survivals, 59% and 42%, respectively compared to patients with related donor transplantation, 66% and 44% (P = 0.241). In conclusion, these results suggest that URD in MM is feasible. The small number of patients with URD emphasizes the need to delineate indications and perform prospective protocols.     

Whole-arm t (X;17) (Xp17q;Xq17p) and gonadal dysgenesis

A 19-year-old female patient with gonadal dysgenesis and a de novo t(X;17) (Xp17q;Xq17p) is described. Since the critical segment Xq13----q26 was intact, this case is a further exception to the critical region hypothesis.