Trisomy 12 compromises the mesendodermal differentiation propensity of human pluripotent stem cells

Trisomy 12 is one of the most frequent chromosomal abnormalities in cultured human pluripotent stem cells (hPSCs). Although potential oncogenic properties and augmented cell cycle caused by trisomy 12 have been reported, the consequences of trisomy 12 in terms of cell differentiation, which is the basis for regenerative medicine, drug development, and developmental biology studies, have not yet been investigated. Here, we report that trisomy 12 compromises the mesendodermal differentiation of hPSCs. We identified sublines of hPSCs carrying trisomy 12 after their prolonged culture. Transcriptome analysis revealed that these hPSC sublines carried abnormal gene expression patterns in specific signaling pathways in addition to cancer-related cell cycle pathways. These hPSC sublines showed a lower propensity for mesendodermal differentiation in embryoid bodies cultured in a serum-free medium. BMP4-induced exit from the self-renewal state was impaired in the trisomy 12 hPSC sublines, with less upregulation of key transcription factor gene expression. As a consequence, the differentiation efficiency of hematopoietic and hepatic lineages was also impaired in the trisomy 12 hPSC sublines. We reveal that trisomy 12 disrupts the genome-wide expression patterns that are required for proper mesendodermal differentiation.

Prenatal diagnosis of mosaicism for trisomy 12 in a single colony at amniocentesis in a pregnancy with a favorable outcome

OBJECTIVE

We present prenatal diagnosis of mosaicism for trisomy 12 in a single colony at amniocentesis with a favorable outcome.

CASE REPORT

A 36-year-old woman underwent amniocentesis at 18 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 47,XY,+12[1]/46,XY[14]. In 15 colonies of cultured amniocytes, all three cells in one colony had the karyotype of 47,XY,+12, while the rest 14 colonies had the karyotype of 46,XY. The parental karyotypes were normal. Prenatal ultrasound findings were unremarkable. Polymorphic DNA marker analysis using the DNAs extracted from cultured amniocytes and parental bloods excluded uniparental disomy (UPD) 12. At 37 weeks of gestation, a healthy 2,828-g male baby was delivered with no phenotypic abnormality. The cord blood had a karyotype of 46,XY in 40/40 lymphocytes. Postnatal interphase fluorescence in situ hybridization (FISH) analysis on buccal cells and urinary cells revealed normal signals in 72/72 buccal cells, and trisomy 12 signals in 1/47 (2.1%) urinary cells compared with 0% (0/75 cells) of trisomy 12 signals in the normal control.

CONCLUSION

Mosaicism for trisomy 12 in a single colony at amniocentesis without UPD 12 and fetal ultrasound abnormalities can be associated with a favorable outcome.

Prenatal diagnosis of mosaicism for double trisomies of trisomy 11 and trisomy 12 in a single colony at amniocentesis in a pregnancy with a favorable outcome

OBJECTIVE

We present prenatal diagnosis of mosaicism for double trisomies of trisomy 11 and trisomy 12 in a single colony at amniocentesis with a favorable outcome.

CASE REPORT

A 23-year-old woman underwent amniocentesis at 24 weeks of gestation because of congenital bowel dilation in the fetus. Amniocentesis revealed a karyotype of 48,XX,+11,+12[1]/46,XX[24]. In 25 colonies of cultured amniocytes, all five cells in one colony had the karyotype of 48,XX,+11,+12, while the rest 24 colonies had the karyotype of 46,XX. The parental karyotypes were normal. Repeat amniocentesis was performed at 26 weeks of gestation. Interphase fluorescence in situ hybridization (FISH), array comparative genomic hybridization (aCGH) and quantitative fluorescent polymerase chain reaction (QF-PCR) were applied on the uncultured amniocytes, and conventional cytogenetic analysis was applied on cultured amniocytes. Interphase FISH analysis showed no trisomy 11 signal and no trisomy 12 signal in 102 uncultured amniocytes. QF-PCR analysis excluded uniparental disomy (UPD) 11 and UPD 12. aCGH analysis showed no genomic imbalance. The cultured amniocytes at repeat amniocentesis had the karyotype of 46,XX in 13/13 colonies. At term, a healthy 3445-g female baby was delivered with no phenotypic abnormality except imperforate anus and a perianal fistula. The cord blood had a karyotype of 46,XX in 40/40 lymphocytes. Postnatal interphase FISH analysis of buccal cells and urinary cells revealed trisomies 11 and 12 signals in 11/111 (9.9%) buccal cells compared with 3% in normal control, and in 3/103 (2.9%) urinary cells compared with 0.98% in normal control.

CONCLUSION

Mosaicism for double trisomies of trisomy 11 and trisomy 12 in a single colony at amniocentesis without UPD 11 and UPD 12 can be associated with a favorable outcome.

Chronic Lymphocytic Leukemia with Divergent Richter's Transformation into a Clonally Related Classical Hodgkin's and Plasmablastic Lymphoma: A Case Report

Chronic lymphocytic leukemia (CLL) typically pursues a prolonged course. Its transformation into a more aggressive lymphoma occurs in 2-8% of all patients. Most commonly, diffuse large B-cell lymphoma develops. Transformation into a classical Hodgkin's lymphoma (cHL) occurs in <1%. Plasmablastic transformation has been only rarely reported. Cases of synchronous divergent transformation of CLL into a composite lymphoma are exceedingly rare. We describe the unique occurrence of the transformation of a long-standing CLL into a synchronous clonally related cHL as well as plasmablastic lymphoma (PBL) in an 85-year-old female patient. After 10 years of asymptomatic CLL, our patient was treated with a rituximab-chlorambucil scheme in combination with pegfilgrastim for recurrent infections and the development of B symptoms. Five cycles (of six planned) were administrated with no adverse effects. After the fifth cycle, lymphadenopathy with pronounced B symptoms appeared. Histology showed the presence of cHL in the lymph node, while the bone marrow was infiltrated by PBL. Our patient died in sepsis not receiving further specific oncologic treatment due to her poor general condition. Additional cytogenetic and molecular studies showed that this was a case of mutated CLL with trisomies of chromosomes 12, 3, and 18 (a rare specific +12 plus other-non+19 CLL subgroup). The presence of trisomy 12 has also been proved in plasmablasts and in cHL cells.

Mosaic Trisomy 12 Associated with Overgrowth Detected in Fibroblast Cell Lines

Mosaic trisomy 12 is a rare anomaly, and only 9 cases of live births with this condition have been reported in the literature. The clinical phenotype is variable, including neuropsychomotor developmental delay, congenital heart disease, microcephaly, cutaneous spots, facial asymmetry, prominent ears, hypotonia, retinopathy, and sensorineural hearing loss. A 2-year-old female presented with neuropsychomotor developmental delay, prominent forehead, dolichocephaly, patchy skin pigmentation, and unexpected overgrowth at birth. Cytogenetic analysis of her peripheral blood showed normal results, suggesting the presence of a chromosomal alteration in other tissues. Further studies using G-banding and FISH performed on fibroblasts from both hyper- and hypopigmented regions identified a 47,XX,+12/46,XX karyotype. To the best of our knowledge, no patients with mosaic trisomy 12 associated with overgrowth have been reported to date. Congenital overgrowth and neonatal overgrowth have been frequently linked to Pallister-Killian syndrome (PKS; OMIM 601803). This case suggests the possibility of an association of genes present in the 12p region with fetal overgrowth, considering that chromosomal duplications could lead to an increase in the production of aberrant transcripts and disturbing gene dosage effects. This case highlights the importance of cytogenetic analysis in different tissues to provide relevant information to the specific genotype/phenotype correlation.

[Clinical analysis of 70 chronic lymphocytic leukemia patients with trisomy 12 detected by FISH]

目的

总结探讨FISH检测12号染色体三体（CEP12）阳性慢性淋巴细胞白血病（CLL）患者的临床特征、治疗情况及预后。

方法

回顾性分析2003年5月至2015年4月接受FISH检测CEP12的330例CLL患者临床资料，比较CEP12阳性患者（70例）和CEP12阴性患者（260例）临床特征、疗效及预后差异。

结果

与CEP12阴性患者相比，CEP12阳性患者肝肿大（13.6%对4.0%，P=0.011）及LDH>247 U/L（43.3%对18.5%，χ²=15.892，P<0.001）比例更高，而发病年龄、性别、临床分期、β₂微球蛋白水平、IGHV突变比例及脾脏/淋巴结肿大等方面差异无统计学意义。CEP12阳性与阴性患者比较，FMC7阳性率更高（23.8%对12.7%，χ²=4.730，P=0.030），CD23阳性率更低（95.2%对99.6%，P=0.033）。氟达拉滨组、利妥昔单抗组、传统治疗组总有效率（ORR）分别为77.5%（31/40）、84.8%（56/66）、45.4%（50/110），差异有统计学意义，且传统治疗组ORR均低于氟达拉滨组及利妥昔单抗组；氟达拉滨组中CEP12阳性患者ORR低于CEP12阴性患者（42.9%对84.8%，P=0.034）；而利妥昔单抗组中CEP12阳性患者ORR高于CEP12阴性患者（91.7%对81.0%），但差异无统计学意义（P=0.306）。CEP12阳性患者中位诊断至起始治疗时间为22.6（95%CI 15.4~31.7）个月，中位总生存（OS）时间为118.5（95%CI 74.5~162.4）个月，5年无进展生存（PFS）及OS率分别为（52.9±7.6）%、（74.8±6.6）%。CEP12阳性与阴性患者比较，PFS（χ²=0.410，P=0.478）及OS（χ²=0.052，P=0.180）差异均无统计学意义。

结论

CEP12阳性CLL患者临床肝肿大及LDH增高更为常见，传统治疗疗效最差，单用氟达拉滨疗效不如CEP12阴性患者，但予含利妥昔单抗的治疗方案其疗效与CEP12阴性患者相当。

Activation-induced deaminase and its splice variants associate with trisomy 12 in chronic lymphocytic leukemia

Activation-induced cytidine deaminase (AID) is a mutator enzyme essential for somatic hypermutation (SHM) and class switch recombination (CSR) during effective adaptive immune responses. Its aberrant expression and activity have been detected in lymphomas, leukemias, and solid tumors. In chronic lymphocytic leukemia (CLL) increased expression of alternatively spliced AID variants has been documented. We used real-time RT-PCR to quantify the expression of AID and its alternatively spliced transcripts (AIDΔE4a, AIDΔE4, AIDivs3, and AIDΔE3E4) in 149 CLL patients and correlated this expression to prognostic markers including recurrent chromosomal aberrations, the presence of complex karyotype, mutation status of the immunoglobulin heavy chain variable gene, and recurrent mutations. We report a previously unappreciated association between higher AID transcript levels and trisomy of chromosome 12. Functional analysis of AID splice variants revealed loss of their activity with respect to SHM, CSR, and induction of double-strand DNA breaks. In silico modeling provided insight into the molecular interactions and structural dynamics of wild-type AID and a shortened AID variant closely resembling AIDΔE4, confirming its loss-of-function phenotype.

Second cancers and Richter transformation are the leading causes of death in patients with trisomy 12 chronic lymphocytic leukemia

BACKGROUND

Trisomy 12 (+12) is detected by fluorescence in-situ hybridization (FISH) analysis in up to 20% of patients with chronic lymphocytic leukemia (CLL). Patients with +12 are known to have unique features and to carry an intermediate prognosis.

PATIENTS AND METHODS

In order to better define this large group, we reviewed the characteristics of 250 untreated patients with +12.

RESULTS

When compared to 516 untreated patients negative for +12 by FISH, patients with +12 showed a higher incidence of thrombocytopenia, Richter transformation, and second malignant neoplasms (SMN), in addition to the expected increased rate of CD38 positivity and atypical immunophenotype. At a median follow-up of 51 months, 57% of patients needed first-line treatment; median time to first treatment was 38 months, and on multivariate analysis (MVA), it was found to be shorter in patients with advanced Rai stage, palpable splenomegaly, and deletion of 14q by conventional cytogenetic analysis. The overall response rate with first-line treatment was 94%. The median failure-free survival has not been reached, but on MVA, it was found to be shorter in patients whose disease responded in a manner other than complete remission or with FISH negativity for deletion 13q. The median overall survival for the entire group has not been reached, but MVA revealed it to be shorter in patients with an absolute lymphocyte count of > 30 × 10(9)/L or who developed SMN. Eighteen deaths have been observed so far, and Richter transformation and SMN were the leading causes of death (3 and 6, respectively).

CONCLUSION

Patients with +12 CLL show characteristic clinical and biologic features, and may benefit from increased surveillance for second cancers.

Fluorescence In Situ Hybridization: Trisomy 12 Follow-up In Hairy Cell Leukemia

Peripheral white blood cells from five patients with hairy cell leukemia (HCL) were studied applying fluorescence in situ hybridization (FISH) using heparinized peripheral blood, biotin-labeled chromosome 12-specific α satellite DNA probe and biotin fluorescein-labeled avidin to detect hybridization. This methodology is ideal to investigate the incidence of numerical chromosomal abnormalities of both interphase and metaphase cells. Blood samples from 28 normal subjects were included as control samples. Trisomy 12 was considered to be present when ≥4% of cells had three hybridization spots. Trisomy 12 was detected in three of the five patients at different stages of their evolution. Trisomy 12 was also evident in two patients upon relapse of the HCL. When treatment with interferon alfa (IFN) and steroids was started, clinical and analytical remission were achieved and trisomy 12 disappeared. In one patient trisomy 12 persisted regardless of treatment with IFN and a good clinical evolution. Our results show that trisomy 12 was detected in HCL with FISH at a higher frequency than that previously reported by cytogenetic analysis in either peripheral blood or in cultivated cell lines. These results indicate that the presence of trisomy 12 may be a useful marker for the presence of HCL cells, to check the percentage of trisomic cells and that trisomy 12 is also a useful marker to indicate the activity of the disease.