SBIR-STTR Award

We will utilize conditioned media (CM) from cultures of the nasopharyngeal carcinoma (NPC) cell line CNEI. This cell line was derived from a patient in China and is the only NPC cell line that has been adapted to grow in the absence of serum. Preliminary evidence has established that the CNEI cell line grows by an autocrine mechanism and that CNEI CM contain bFGF and possibly three other novel growth factors that may mediate in part the autocrine growth of the CNEI cell. We also have identified a growth inhibitory activity in CM that blocks growth factor stimulated 3T3 cell growth. Our goals are to purify and characterize both growth stimulatory and inhibitory activities for CNEI CM by established methodologies, to characterize these factors by multiple criteria, and to establish role(s) of these factors in the autocrine growth of CNEI cells. Phase I will be directed to identifying and purifying novel activities to the extent possible within the 6 months available. These new factors will be detection of human NPC nasopharyngeal cancer in primary biopsy and in metastatic tissues and perhaps of antigen in blood for early detection as our long-term goals. These factors also will be used to develop reagents as possible therapeutics. It is hoped to provide new approaches to diagnosis and treatment of human nasopharyngeal carcinoma.Awardee's statement of the potential commercial applications of the research: We will use conditioned media from serum free cultures of human nasopharyngeal carcinoma (NPC) cells to purity autocrine growth factors and inhibitors. The purified proteins and the cDNA clones of these proteins will be used to develop antibodies and other reagents for use in diagnosis and perhaps in treatment of NPC. The commercial potential and benefits to the patients are worldwide.National Cancer Institute (NCI)

During Phase I studies under this proposal, the Investigators found a structurally distinct form of basic fibroblast growth factor (bFGF) which was released from a cell line derived from a human nasopharyngeal carcinoma. They demonstrated that the release of bFGF was not accomplished by increased cell lysis and/or cell death, suggesting that bFGF was released through an active process and that this release might have a functional role in regulating angiogenesis. Release of this factor was also demonstrated in other cell lines with high levels being released from various tumor and transformed cell lines and low or nondetectable levels from normal cell lines when the same number of cells were compared. When they compared transformed and nontransformed cells with the same genetic background, the transformed cells reseated high levels of bFGF. Moreover, they were able to show that the release of bFGF appeared to be regulated at the post transcriptional level. It was enhanced by a specific stimulator of protein kinase activity and thus protein phophorylation appeared to be an essential step in the upregulation of release of bFGF. They analyzed a number of clinical samples and found higher levels of bFGF were present in some patients with neoplasia. This lead to the Phase II application in which the released bFGF will be studied to ascertain ff it can be utilized as a tumor marker for potential clinical diagnosis and as a possible target for anti- angiogenesis therapy.In the current proposal, the Investigators plan to develop a radioimmunoassay for bFGF for the clinical detection and follow-up of patients with various neoplastic disorders. Initially, they plan to generate a panel of monoclonal antibodies with different epitope specificities using recombinant bFGF as the antigen. Epitope specific mAbs will be employed to develop highly sensitive bFGF immuno-assay kits and then they will assess the clinical significance of bFGF release in various cancers using a bFGF immuno-assay system. Secondly, they will initiate efforts to identify, characterize and clone the cDNA to a bFGF binding protein observed in conditioned media from a human hepatocarcinoma cell line. They will employ a bFGF binding protein which they isolated from a human hepatocellular carcinoma cell line in order to use bFGF as a tumor marker and pursue a significance in anti-angiogenesis therapy. In this regard, they plan to generate a bFGF fusion protein by recombinant technology which can be used a specific probe to detect the bFGF binding protein in order to purify and assess the significance of bFGF binding protein. Antibodies against the bFGF binding protein will be generated and tested with clinical samples from patients with cancer. Thus, both the bFGF mAbs and the binding protein will be tested as reagents for clinical testing and then as part of a strategy to develop anti-angiogenesis agents by reducing or eliminating tumor formation in a nude mice model. Lastly, they plan to further purify and characterize other growth factor(s) and growth inhibitors secreted by nasopharyngeal carcinoma cell lines and a human hepatoma cell line.National Cancer Institute (NCI)