Aberrant DNA methylation distorts developmental trajectories in atypical teratoid/rhabdoid tumors

Atypical teratoid/rhabdoid tumors (AT/RTs) are pediatric brain tumors known for their aggressiveness and aberrant but still unresolved epigenetic regulation. To better understand their malignancy, we investigated how AT/RT-specific DNA hypermethylation was associated with gene expression and altered transcription factor binding and how it is linked to upstream regulation. Medulloblastomas, choroid plexus tumors, pluripotent stem cells, and fetal brain were used as references. A part of the genomic regions, which were hypermethylated in AT/RTs similarly as in pluripotent stem cells and demethylated in the fetal brain, were targeted by neural transcriptional regulators. AT/RT-unique DNA hypermethylation was associated with polycomb repressive complex 2 and linked to suppressed genes with a role in neural development and tumorigenesis. Activity of the several NEUROG/NEUROD pioneer factors, which are unable to bind to methylated DNA, was compromised via the suppressed expression or DNA hypermethylation of their target sites, which was also experimentally validated for NEUROD1 in medulloblastomas and AT/RT samples. These results highlight and characterize the role of DNA hypermethylation in AT/RT malignancy and halted neural cell differentiation.

Chromatin and Epigenetic Dysregulation of Prostate Cancer Development, Progression, and Therapeutic Response

The dysregulation of chromatin and epigenetics has been defined as the overarching cancer hallmark. By disrupting transcriptional regulation in normal cells and mediating tumor progression by promoting cancer cell plasticity, this process has the ability to mediate all defined hallmarks of cancer. In this review, we collect and assess evidence on the contribution of chromatin and epigenetic dysregulation in prostate cancer. We highlight important mechanisms leading to prostate carcinogenesis, the emergence of castration-resistance upon treatment with androgen deprivation therapy, and resistance to antiandrogens. We examine in particular the contribution of chromatin structure and epigenetics to cell lineage commitment, which is dysregulated during tumorigenesis, and cell plasticity, which is altered during tumor progression.

Lung function impairment following mycoplasmal and other acute pneumonias

We prospectively studied the lung function of 106 consecutive young patients with pneumonia. At the time of hospital admission we observed impaired spirometric function in 48% of the patients. During and following treatment, the frequency of abnormalities in pulmonary function tests decreased rapidly. However, at the 15th day of hospitalization, abnormal ventilatory function was still demonstrated in 21% of the patients. Such prolonged impairment of ventilatory function was significantly more likely to result from pneumonia caused by Mycoplasma pneumoniae than from forms caused by adenovirus or Streptococcus pneumoniae.

Lung function impairment following mycoplasmal and other acute pneumonias

We prospectively studied the lung function of 106 consecutive young patients with pneumonia. At the time of hospital admission we observed impaired spirometric function in 48% of the patients. During and following treatment, the frequency of abnormalities in pulmonary function tests decreased rapidly. However, at the 15th day of hospitalization, abnormal ventilatory function was still demonstrated in 21% of the patients. Such prolonged impairment of ventilatory function was significantly more likely to result from pneumonia caused by Mycoplasma pneumoniae than from forms caused by adenovirus or Streptococcus pneumoniae.