No abstract

Breast cancer (BC) brain metastases is a life-threatening condition to which accounts the poor understanding of BC cells’ (BCCs) extravasation into the brain, precluding the development of preventive strategies. Thus, we aimed to unravel the players involved in the interaction between BCCs and blood–brain barrier (BBB) endothelial cells underlying BBB alterations and the transendothelial migration of malignant cells. We used brain microvascular endothelial cells (BMECs) as a BBB in vitro model, under conditions mimicking shear stress to improve in vivo-like BBB features. Mixed cultures were performed by the addition of fluorescently labelled BCCs to distinguish individual cell populations. BCC–BMEC interaction compromised BBB integrity, as revealed by junctional proteins (β-catenin and zonula occludens-1) disruption and caveolae (caveolin-1) increase, reflecting paracellular and transcellular hyperpermeability, respectively. Both BMECs and BCCs presented alterations in the expression pattern of connexin 43, suggesting the involvement of the gap junction protein. Myosin light chain kinase and phosphorylated myosin light chain were upregulated, revealing the involvement of the endothelial cytoskeleton in the extravasation process. β4-Integrin and focal adhesion kinase were colocalised in malignant cells, reflecting molecular interaction. Moreover, BCCs exhibited invadopodia, attesting migratory properties. Collectively, hub players involved in BC brain metastases formation were unveiled, disclosing possible therapeutic targets for metastases prevention.

No abstract

Among breast cancer (BC) patients, 15–25% develop BC brain metastases (BCBM), a severe condition due to the limited therapeutic options, which points to the need for preventive strategies. We aimed to find a drug able to boost blood–brain barrier (BBB) properties and prevent BC cells (BCCs) extravasation, among PI3K, HSP90, and EGFR inhibitors and approved drugs. We used BCCs (4T1) and BBB endothelial cells (b.End5) to identify molecules with toxicity to 4T1 cells and safe for b.End5 cells. Moreover, we used those cells in mixed cultures to perform a high-throughput microscopy screening of drugs’ ability to ameliorate BBB properties and prevent BCCs adhesion and migration across the endothelium, as well as to analyse miRNAs expression and release profiles. KW-2478, buparlisib, and minocycline hydrochloride (MH) promoted maximal expression of the junctional protein β-catenin and induced 4T1 cells nucleus changes. Buparlisib and MH further decreased 4T1 adhesion. MH was the most promising in preventing 4T1 migration and BBB disruption, tumour and endothelial cytoskeleton-associated proteins modifications, and miRNA deregulation. Our data revealed MH’s ability to improve BBB properties, while compromising BCCs viability and interaction with BBB endothelial cells, besides restoring miRNAs’ homeostasis, paving the way for MH repurposing for BCBM prevention.

No abstract

No abstract

No abstract

Hemangiomas are usually diagnosed based on ultrasound findings. The presence of symptoms, rapid growth or atipical imagiological findings should make us consider other diagnoses, including malignant tumors such as angiosarcomas. We describe the case of a previously healthy 46-year-old female without a history of exposure to carcinogens who presented with abdominal pain for two months. Diagnostic work-up revealed elevated gamma-glutamyl transferase and lactate dehydrogenase levels. Abdominal ultrasound described a large nodular lesion in the right lobe of the liver described as a hemangioma. One month later, a computed tomography-scan was made and revealed the same lesion, which had grown from 13.5 to 20 cm, maintaining typical imaging characteristics of a hemangioma. A right hepatectomy was performed and pathology revealed an angiosarcoma. After surgery, a positron emission tomography-computed tomography scan showed hepatic and bone metastasis. The patient started taxane-based chemotherapy and lumbar palliative radiotherapy, but died 10 months after surgery. This case shows how difficult it is to diagnose hepatic angiosarcoma relying only on imaging findings. Two abdominal computed tomography -scans were performed and none suggested this diagnosis. Angiosarcoma is a very aggressive tumour with an adverse prognosis. Surgery is the only curative treatment available. However, it is rarely feasible due to unresectable disease or distant metastasis.