A diverse group of vascular neoplasms that typically feature a red or blue nodular appearance and exhibit characteristics between those of a benign hemangioma and malignant angiosarcoma are known as hemangioendotheliomas. The EOMA cell line was initiated in the early 1980s from a mixed murine hemangioendothelioma excised from an adult member of the species Mus musculus.

EOMA hemangioendothelioma cells synthesize a variety of substances, such as angiotensin-converting enzyme (ACE), endostatin, interleukin-6, thrombospondin, and cathepsin L. EOMA cells also express surface receptors for acetylated low-density lipoprotein and vascular addressin, a cell adhesion molecule unique to endothelial tissues. Studies show that EOMA cells stimulate tumor growth in syngeneic mice.

Hemangioendotheliomas are commonly characterized by vein dilation and congestion accompanied by inactive endothelial cell nuclei and intermittent thrombi or phleboliths. Epitheloid or spindle-shaped mesenchymal cells arranged into sheets may also occur in the region of the neoplasm, often intermingled with the abnormal blood vessels. The seriousness of hemangioendotheliomas, as well as many other tumor types, varies significantly. Metastases may occur in some cases and recurrence following removal is possible. Hemangioendotheliomas are rare in children and affect men and women at approximately equal rates. Hemangioendothelioma growth in some patients is related to the early development of varicose veins, Maffucci's syndrome, lymphedema, or other medical conditions.

The adherent monolayer EOMA cell culture presented in the digital image above was labeled for the cytoskeletal filamentous actin and intracellular mitochondrial networks with BODIPY FL conjugated to phalloidin (yielding green emission) and MitoTracker Orange CMTMRos, respectively. Nuclei present in the endothelial cells were counterstained with the DNA-selective bisbenzimide dye, Hoechst 33342 (blue emission). Images were recorded in grayscale with a 12-bit digital camera coupled to either a Nikon E-600 or Eclipse 80i microscope equipped with bandpass emission fluorescence filter optical blocks. During the processing stage, individual image channels were pseudocolored with RGB values corresponding to each of the fluorophore emission spectral profiles.

Proximity of the F-Actin and Mitochondrial Networks in EOMA Cell Cultures - The mitochondria present in the culture of mouse hemangioendothelioma cells featured in this section were labeled with MitoTracker Red CMXRos, a derivative of X-rosamine. In addition, the culture was labeled for the cytoskeletal F-actin network and DNA in the cell nucleus with Alexa Fluor 488 conjugated to phalloidin and DAPI, respectively.

Mouse Hemangioendothelioma Cells Triple Labeled with Alexa Fluor 633, MitoTracker Orange CMTMRos, and SYTOX Green - A log phase culture of EOMA endothelial cells was stained for filamentous actin with Alexa Fluor 633 conjugated to phalloidin and for mitochondria with MitoTracker Orange CMTMRos. Cell nuclei were counterstained with the classic nucleic acid stain SYTOX Green.

Targeting Actin, Mitochondria, and DNA in Cultured Murine Endothelial Cells - A BODIPY FL-phalloidin conjugate was utilized to fluorescently label the cytoskeletal filamentous actin network of the mouse hemangioendothelioma cell culture presented in this section. The cells were also treated with the probes MitoTracker Orange CMTMRos and Hoechst 33342 to target mitochondria and DNA in the cell nucleus.