The origin of genomic N6-methyl-deoxyadenosine in mammalian cells.

The proposal that N6-methyl-deoxyadenosine (m6dA) acts as an epigenetic mark in mammals remains controversial. Using isotopic labeling coupled to ultrasensitive mass spectrometry, we confirm the presence of low-level m6dA in mammalian DNA. However, the bulk of genomic m6dA originates from ribo-N6-methyladenosine, which is processed via the nucleotide-salvage pathway and misincorporated by DNA polymerases. Our results argue against m6dA acting as a heritable, epigenetic DNA mark in mammalian cells.

Primary metastatic leiomyosarcoma of the fallopian tube: a rare case report.

BACKGROUND: Leiomyosarcoma of the fallopian tube is an extremely unusual gynecologic neoplasm. Since 1886, only 19 of about 35 sarcomas of the fallopian tube have been identified as leiomyosarcomas. As such, clinical diagnosis and therapy management are difficult. CASE REPORT: We report on the case of a 59-year-old woman with leiomyosarcoma of the fallopian tube and liver metastases at the time of diagnosis. After initial tumor debulking, she received palliative chemotherapy with gemcitabine 900 mg/m(2) (d1+8) and docetaxel 100 mg/m(2) (d8) (q21). For additional bone metastases, she started local radiation plus bisphosphonates (q28). After 2 cycles of chemotherapy, the disease progressed, and the patient died within 8 months of diagnosis. A review of the literature is given. CONCLUSIONS: Primary metastatic leiomyosarcoma of the fallopian tube is a progressive disease with limited therapy options. For better prognostic evaluation and disease management in such rare cases, it is important to report and compare more cases regarding course of disease and outcome.

Reversible foetal cerebral ventriculomegaly and cardiomyopathy under chemotherapy for maternal AML.

BACKGROUND: Leukaemia in pregnancy is a rare complication demanding a multidisciplinary approach and careful management to handle potential complications and cope with ethical dilemmas. PATIENT AND METHODS: We report on a patient with acute myeloid leukaemia (AML) relapse in 22 weeks of gestation who received chemotherapy with cytarabine and mitoxantrone, as well as fludarabine, cytarabine, idarubicin, and gemtuzumabozogamicin. We describe findings on regular ultrasound examinations and successful management of complications. RESULTS: The foetus developed signs of anthracycline-induced cardiomyopathy, transient cerebral ventriculomegaly, anaemia, and intrauterine growth restriction. The child was delivered by Caesarean section at 33 + 1 weeks of gestation. The newborn showed no congenital malformations. CONCLUSION: This case report confirms that chemotherapy for treatment of AML can be applied in the second trimester of pregnancy under close and careful maternal and foetal monitoring.

Amplification of NOTCH1 and ABL1 gene loci is a frequent aberration in enteropathy-type T-cell lymphoma.

We have shown previously that amplification of chromosomal region 9q34 is the most frequent aberration in enteropathy-type T-cell lymphoma (ETL). To determine the minimum amplified 9q34 region and identify possible candidate gene(s), we performed a detailed microsatellite screening and quantitative real-time PCR (QPCR) on 26 ETL cases. Microsatellite analysis revealed allelic imbalance in both ABL1 and NOTCH1 gene loci (microsatellites D9S290-D9S1847 and D9S158 flanking the former and latter genes, respectively) localized in the band 9q34. The results were confirmed by TaqMan-based QPCR showing amplification of ABL1 and NOTCH1 exons in 50% and 65% of cases, respectively. Amplifications of the NOTCH1 gene were more frequent than of the ABL1 gene; moreover, the analyzed NOTCH1 exon consistently displayed higher levels of amplification than ABL1 coding sequences. From 9q34 known genes, NOTCH1 could thus be the primary target of genomic DNA amplification in ETL.

High frequency of genetic aberrations in enteropathy-type T-cell lymphoma.

To define genetic aberrations playing a role in the development of enteropathy-type T-cell lymphoma (ETL), we examined 26 such tumors using a battery of 47 microsatellite markers. The most frequent aberration (seen in 40% of informative genotypes) was amplification of genomic material in region 9q34 encompassing c-abl and Notch-1 gene loci. Other frequent amplifications were detected in regions 5q33.3-34 and 7q31 (both in more than 30%). Multiple losses of heterozygosity were detected in 6p24, 7p21, 17q23-25, regions containing putative tumor suppressor genes, and in the p53 locus in 17p13.1. Analysis of the pattern of occurrence of these aberrations revealed existence of two ETL subgroups: one of them characterized by the 9q34 aberration and another smaller one showing allelic imbalances in 3q27. These two aberrations were mutually exclusive. Microsatellite instability (MSI) was detected in 69% of the examined lymphomas; the percentage of MSI-positive genotypes per tumor ranged from 2% to 12%. The spectrum of genetic alterations detected showed patterns dependent on morphology. Monomorpic ETLs displayed frequently biallelic TCR-gamma gene rearrangement (p = 0078, chi(2) test). They showed a different pattern and fewer allelic imbalances (no 3q27, 4q28, 13q14, fewer 5q21, or 5q33.3-34 aberrations) and a lower frequency of MSI than pleomorphic ETLs.