5-Aminolevulinic Acid Fluorescence Indicates Perilesional Brain Infiltration in Brain Metastases.

Background: In glioma surgery, 5-aminolevulinic acid (5-ALA) fluorescence reflects tumor infiltration, and fluorescence-assisted resection correlates with higher removal rates and improved progression-free survival. Recent studies report that a sizable proportion of brain metastases exhibit peritumoral infiltration on the cellular level. There is little information regarding whether 5-ALA is useful to guide surgery in the peritumoral zone in metastases.

LEF1 supports metastatic brain colonization by regulating glutathione metabolism and increasing ROS resistance in breast cancer.

More than half of all brain metastases show infiltrating rather than displacing growth at the macro-metastasis/organ parenchyma interface (MMPI), a finding associated with shorter survival. The lymphoid enhancer-binding factor-1 (LEF1) is an epithelial-mesenchymal transition (EMT) transcription factor that is commonly overexpressed in brain-colonizing cancer cells. Here, we overexpressed LEF1 in an in vivo breast cancer brain colonization model.

PI3K: A master regulator of brain metastasis-promoting macrophages/microglia.

Mutations and activation of the PI3K signaling pathway in breast cancer cells have been linked to brain metastases. However, here we describe that in some breast cancer brain metastases samples the protein expression of PI3K signaling components is restricted to the metastatic microenvironment. In contrast to the therapeutic effects of PI3K inhibition on the breast cancer cells, the reaction of the brain microenvironment is less understood.

The metastatic infiltration at the metastasis/brain parenchyma-interface is very heterogeneous and has a significant impact on survival in a prospective study.

Unlabelled: The current approach to brain metastases resection is macroscopic removal of metastasis until reaching the glial pseudo-capsule (gross total resection (GTR)). However, autopsy studies demonstrated infiltrating metastatic cells into the parenchyma at the metastasis/brain parenchyma (M/BP)-interface.

Aims/methods: To analyze the astrocyte reaction and metastatic infiltration pattern at the M/BP-interface with an organotypic brain slice coculture system.

Tumor-derived microvesicles mediate human breast cancer invasion through differentially glycosylated EMMPRIN.

Tumor cells secrete not only a variety of soluble factors, but also extracellular vesicles that are known to support the establishment of a favorable tumor niche by influencing the surrounding stroma cells. Here we show that tumor-derived microvesicles (T-MV) also directly influence the tumor cells by enhancing their invasion in a both autologous and heterologous manner. Neither the respective vesicle-free supernatant nor MV from benign mammary cells mediate invasion.

Carcinoma cells misuse the host tissue damage response to invade the brain.

The metastatic colonization of the brain by carcinoma cells is still barely understood, in particular when considering interactions with the host tissue. The colonization comes with a substantial destruction of the surrounding host tissue. This leads to activation of damage responses by resident innate immune cells to protect, repair, and organize the wound healing, but may distract from tumoricidal actions.

Microglia promote colonization of brain tissue by breast cancer cells in a Wnt-dependent way.

Although there is increasing evidence that blood-derived macrophages support tumor progression, it is still unclear whether specialized resident macrophages, such as brain microglia, also play a prominent role in metastasis formation. Here, we show that microglia enhance invasion and colonization of brain tissue by breast cancer cells, serving both as active transporters and guiding rails. This is antagonized by inactivation of microglia as well as by the Wnt inhibitor Dickkopf-2.

Intra-osseous ultrasound for pedicle screw positioning in the subaxial cervical spine: an experimental study.

Background: In contrast to other regions of the human spine, dorsal fixation with rods and pedicle screws is comparatively rarely performed in the cervical spine. Although this technique provides a higher mechanical strength than the more frequently used lateral mass screws, many surgeons fear the relatively high rate of misplacements. This higher incidence is mainly due to the complex vertebral anatomy in this spinal segment.

Antidiabetic PPAR gamma-activator rosiglitazone reduces MMP-9 serum levels in type 2 diabetic patients with coronary artery disease.

Background: Matrix metalloproteinases (MMPs) are critically involved in the development of unstable plaques. Although arteriosclerotic lesions in patients with diabetes mellitus are more unstable than those of nondiabetic subjects, nothing is known about serum levels of MMPs in these patients or about mechanisms to modulate MMP levels. We investigated MMP levels in diabetic and nondiabetic coronary artery disease (CAD) patients and performed a clinical trial to assess the effect of the PPARgamma-activating, antidiabetic thiazolidinedione rosiglitazone on MMP levels in diabetic CAD patients.