Intraparenchymal mesenchymal chondrosarcoma of the frontal lobe--a case report and molecular detection of specific gene fusions from archival FFPE sample.

Mesenchymal chondrosarcoma is a rare tumor of cartilaginous origin characterized by its bimorphic pattern composed of highly undifferentiated small round cells separated by islands of well-differentiated hyaline cartilage. It exhibits higher malignancy and earlier occurrence in comparison to classic chondrosarcomas. Recently identified HEY1-NCOA2 and IRF2BP2-CDX1 gene fusions confirm their distinct molecular origin and pose a promising diagnostic marker. The majority of cases arise from craniofacial bones. In this study, we present a rare case of mesenchymal chondrosarcoma encompassed within the brain parenchyma of the frontal lobe without any dural or bone attachment. We demonstrate histopathological findings and confirm the HEY1-NCOA2 gene fusion in a formalin-fixed paraffin-embedded archival sample using simple reverse transcription polymerase chain reaction (RT-PCR) method. IRF2BP2-CDX1 gene fusion was absent in the analyzed sample. The clinical follow-up is also presented with a review of treatment modalities for this entity.

Statins inhibit ABCB1 and ABCG2 drug transporter activity in chronic myeloid leukemia cells and potentiate antileukemic effects of imatinib.

Despite undisputed success of tyrosine kinase inhibitors in the therapy of chronic myeloid leukemia (CML), development of drug resistance and inability to cure the disease challenge clinicians and researchers. Additionally, recent reports regarding cardiovascular toxicities of second and third generation tyrosine kinase inhibitors prove that there is still a place for novel therapeutic combinations in CML. We have previously shown that statins are able to modulate activity of chemotherapeutics or antibodies used in oncology. Therefore, we decided to verify that statins are able to potentiate antileukemic activity of imatinib, still a frontline treatment of CML. Lovastatin, a cholesterol lowering drug, synergistically potentiates antileukemic activity of imatinib in cell lines and in primary CD34+ CML cells from patients in different phases of the disease, including patients resistant to imatinib with no detectable mutations. This effect is related to increased intracellular concentration of imatinib in CD34+ CML cells and cell lines measured using uptake of (14)C-labeled imatinib. Lovastatin does not influence influx but significantly inhibits efflux of imatinib mediated by ATP-binding cassette (ABC) transporters: ABCB1 and ABCG2. The addition of cholesterol completely reverses these effects. Statins do not affect expression of ABCB1 and ABCG2 genes. The effects are drug-class specific, as observed with other statins. Our results suggest that statins may offer a valuable addition to imatinib in a select group of CML patients.