Comparative proteomic profiling of tumor progression in fibrosarcoma

Proc Amer Assoc Cancer Res, Volume 47, 2006 1840 Our investigations are directed towards gaining a better understanding of the molecular mechanisms involved in the progression of fibrosarcoma. These highly invasive and difficult to manage mesenchymal tumors afflict ∼11,000 individuals each year in the US and result in a 5-year mortality rate of ∼ 50% due to the development of lung metastases. In order to elucidate changes in protein expression that accompany malignant progression in fibrosacoma, comparative proteomic profiling studies were conducted on matched sets of cell lines from primary tumors and corresponding post-surgical recurrences obtained from a well-characterized feline model of the disease. These cells lines have previously been characterized for in vitro and in vivo growth properties demonstrating malignant progression from primary non-metastatic tumor to metachronous local recurrence with potential for distal metastasis. Using the method of Difference In Gel Electrophoresis (DIGE), Cy3 labeled primary tumor cell proteins & Cy5 labeled proteins obtained from recurrent tumor cells were subjected to iso-electric focusing between the pH range of 4 through 7 followed by SDS PAGE through a 8.5 cm long 4-20% gradient gel. Visualization of labeled proteins on an Amersham Typhoon 8600 Imager and data analysis using the DeCyder Diffrential Analysis Software helped identify several dysregulated proteins in the experimental model which could be confirmed through repetition of the experiment. As shown in the [table][1] below, 26 spots were up or down regulated by > 2.5 fold while 140 other spots were also significantly altered between 1.5-2.5 fold. These leads are being identified by tandem mass spectrometry and validated by real-time PCR and immunohistochemical methods. Overall, the results of our studies show that comparative analysis using both human and feline fibrosarcoma samples has great potential for enhancing our understanding of key molecular components that are altered during the malignant progression of fibrosarcoma, particularly as relates to the development of aggressive biological characteristics. ![Figure][2] [1]: #F1 [2]: pending:yes