Combination of Introgen's Nanoparticles Demonstrate Increased Efficacy in the Treatment of Metastatic Lung Cancer.

p53 and FUS1 Tumor Suppressors Work Synergistically to Kill Cancer without Harming Normal Cells

AUSTIN, Texas -- Two powerful tumor suppressor genes, p53 and FUS1, administered intravenously in nanoparticle formulations were capable of significantly shrinking metastatic tumors in models of human lung cancer, according to investigators at The University of Texas M. D. Anderson Cancer Center. Molecular cancer therapies using these genes, p53 and FUS1, are in clinical-stage development by Introgen Therapeutics (NASDAQ:INGN). The technologies are included in a broad portfolio of intellectual properties licensed exclusively to Introgen from M. D. Anderson Cancer Center and other institutions.

The study, published in the January 15 issue of the journal Cancer Research, found that each of the nanoparticle tumor suppressors was effective therapy but more powerful results were observed when the treatments were combined. Systemic therapy with combined p53 and FUS1 nanoparticles in disseminated, metastatic lung cancers decreased the number of human lung tumors by 75 percent and cut their size by 80 percent. The studies also showed that the nanoparticle treatments had no demonstrable adverse effects on normal cells.

Abnormalities of the p53 and FUS1 tumor suppressors are among the most common molecular defects found in human cancers. The mechanism of the increased activity of the combined therapy was determined. The restoration of FUS1 function prevented the breakdown of the administered p53 resulting in its increased ability to destroy tumor cells.

This novel treatment strategy [?] the first time that two functional tumor suppressor genes have been used in a nanoparticle treatment [?] may offer a promising clinical treatment for lung and other cancers, according to lead author Lin Ji, Ph.D., assistant professor in the Department of Thoracic & Cardiovascular Surgery research at M. D. Anderson.

Robert E. Sobol, M.D., Introgen's senior vice president, Medical and Scientific Affairs stated, "These results further support our continued clinical development of p53 and FUS1 tumor suppressor therapies. These nanoparticle formulations facilitate treatment of disseminated cancers and validate the important concept of combining tumor suppressors selected to work synergistically in killing cancer cells while leaving normal cells unharmed."

In this study, the researchers tested the combined FUS1/p53 nanoparticles against four different human lung cancers as well as in normal non-cancerous cells. The treatment dramatically inhibited tumor cell growth in all four lung cancers tested, they said. It also induced cell death in the tumors, likely through the activation of p53 and FUS1 mediated gene functions that resulted in the killing of cancer cells but not normal cells.

Introgen Therapeutics, Inc. is a biopharmaceutical company focused on the discovery, development and commercialization of targeted molecular therapies for the treatment of cancer and other diseases. Introgen is developing molecular therapeutics, immunotherapies, vaccines and nano-particle therapies to treat a wide range of cancers using tumor suppressors and cytokines. Introgen maintains integrated research, development, manufacturing, clinical and regulatory departments and operates multiple manufacturing facilities including a commercial scale cGMP manufacturing facility.

Statements in this release that are not strictly historical may be "forward-looking" statements, including those relating to Introgen's future success with its clinical development program with p53 and FUS1 for treatment of cancer or other diseases. The actual results may differ from those described in this release due to risks and uncertainties that exist in Introgen's operations and business environment, including Introgen's stage of product development and the limited experience in the development of gene-based drugs in general, dependence upon proprietary technology and the current competitive environment, history of operating losses and accumulated deficits, reliance on collaborative relationships, and uncertainties related to clinical trials, the safety and efficacy of Introgen's product candidates, the ability to obtain the appropriate regulatory approvals, Introgen's patent protection and market acceptance, as well as other risks detailed from time to time in Introgen's filings with the Securities and Exchange Commission including its filings on Form 10-K and Form 10-Q. Introgen undertakes no obligation to publicly release the results of any revisions to any forward-looking statements that reflect events or circumstances arising after the date hereof.

Editor's Note: M. D. Anderson Cancer Center also issued a news release about this publication. It may be found at www.mdanderson.org.

Editor's Note: For more information on Introgen Therapeutics, or for a menu of archived press releases, please visit Introgen's Website at: www.introgen.com.