Laser speckle contrast analysis (LASCA) technology for the semiquantitative measurement of angiogenesis in in-ovo-tumor-model.

BACKGROUND: The process of angiogenesis is a key element for tumor growth and proliferation and therefore one of the determining factors for aggressiveness and malignancy. A better understanding of the underlying processes of tumor induced angiogenesis is crucial for superior cancer treatment. Furthermore, the PeriCam perfusion speckle imager (PSI) system high resolution (HR) model by PERIMED presents a noninvasive method for semi-quantitative measurement of blood perfusion, based on laser speckle contrast analysis (LASCA). Aim of the present study was to utilize the chick chorioallantoic membrane (CAM) model as an in-ovo-tumor-model which enables rapid neovascularization of tumors while allowing real-time observation of the microcirculation via LASCA. METHODS: Fertilized chicken eggs were grafted with embryonal/alveolar rhabdomyosarcoma cells or primary sarcoma tumors. The blood perfusion was measured before and after tumor growth using LASCA. The procedure is accelerated and simplified through the integrated PIMSoft software which provides real-time graphs and color-coded images during the measurement. RESULTS: Sarcoma cells and primary sarcoma tumors exhibited satisfactory growth processes on the CAM. LASCA visualized microcirculation accurately and enabled an extensive investigation of the angiogenic potential of sarcoma cells on the CAM. We were able to show that sarcoma cells and primary sarcoma tumors induced larger quantities of neovasculature on the CAM than the controls. CONCLUSIONS: The utilization of LASCA for the investigation of tumor angiogenesis within the CAM model appears to be a highly beneficial, cost-efficient and easily practicable procedure. The proposed model can be used as a drug-screening model for individualized cancer therapy, especially with regards to anti-angiogenic agents.

Incorporation of ophiobolin a into novel chemoembolization particles for cancer cell treatment.

PURPOSE: To design and synthesize chemoembolization particles for the delivery of Ophiobolin A (OphA), a promising fungal-derived chemotherapeutic, directly at the tumour location. To investigate cell death mechanism of OphA on a Rhabdomyosarcoma cancer (RD) cell line. Rhabdomyosarcoma is the most common soft tissue sarcoma in children; with a 5-year survival rate of between 30 and 65%. METHODS: Multimodal chemoembolization particles were prepared by sintering mesoporous silica nanoparticles, prepared by the sol-gel method, onto the surface of polystyrene microspheres, prepared by suspension copolymerisation. The chemoembolization particles were subsequently loaded with OphA. The effects of OphA in vitro were characterised by flow cytometry and nanoparticle tracking analysis (NanoSight). RESULTS: High loading of OphA onto the chemoembolization particles was achieved. The subsequent release of OphA onto RD cells in culture showed a 70% reduction in cell viability. OphA caused RD cells to round up and their membrane to bleb and caused cell death via apoptosis. OphA caused both an increase in the number of microvesicles produced and an increase in DNA content within these microvesicles. CONCLUSIONS: The prepared chemoembolization particles showed good efficacy against RD cells in culture.

Alternative prognostic factors in pediatric embryonal rhabdomyosarcoma: Nm23 expression, proliferative activity and angiogenesis.

Possible clinical relevance of Nm23 expression, angiogenesis and proliferative activity were evaluated as prognostic parameters in childhood embryonal rhabdomyosarcoma (RMS). Specimens of 25 RMS cases were studied for Nm23 antigen immunohistochemically. Vascular surface density (VSD) and number of vessels per stroma (NVES) calculated by stereologic methods on labeling sections with CD34 antibody. For evaluation of proliferative activity of tumors, mitotic figures and Ki67 positive cells were investigated. All findings were searched statistically. Five patients were stage 1 (20%), two were stage 2 (8%), 15 were stage 3 (60%) and three were stage 4 (12%). The mean event free survival (EFS) was 20.8 and the mean overall survival (OS) was 25.9 months. Sixteen patients (64%) were alive and without disease. The percentage of Nm23 positivity was 52%. Log rank analysis showed Nm23 as a predictor for survival (p=0.0313). In Pearson correlation analysis, there was statistical significance between OS and presence of Nm23 expression (p=0.044). VSD was also positively related with EFS (p=0.040). Despite the present parameters in use, there is a need for new prognostic markers, especially to predict the outcome of patients. These findings suggested that Nm23 expression and VSD might be useful for follow-up in RMS.

In vivo imaging of tumor-propagating cells, regional tumor heterogeneity, and dynamic cell movements in embryonal rhabdomyosarcoma.

Embryonal rhabdomyosarcoma (ERMS) is an aggressive pediatric sarcoma of muscle. Here, we show that ERMS-propagating potential is confined to myf5+ cells and can be visualized in live, fluorescent transgenic zebrafish. During early tumor growth, myf5+ ERMS cells reside adjacent normal muscle fibers. By late-stage ERMS, myf5+ cells are reorganized into distinct regions separated from differentiated tumor cells. Time-lapse imaging of late-stage ERMS revealed that myf5+ cells populate newly formed tumor only after seeding by highly migratory myogenin+ ERMS cells. Moreover, myogenin+ ERMS cells can enter the vasculature, whereas myf5+ ERMS-propagating cells do not. Our data suggest that non-tumor-propagating cells likely have important supportive roles in cancer progression and facilitate metastasis.

[A case of surgically removed retroperitoneal rhabdomyosarcoma in a child requiring vascular reconstruction]. / Sudovi rekonstruktsii pri radikalno otstraniavane na retroperitonealen rabdomiosarkom u dete.

Retroperitoneal tumors engaging large vessels require vascular reconstruction when surgically removed. We present a case of retroperitoneal rhabdomiosarcoma in a child, which required inferior vena cava (IVC) grafting, creating a new bifurcation of IVC, and an A-V fistula between greater saphenous vein and femoral artery as well as grafting of right common iliac artery.