• E-mail
• Print
• Comment
• Font Size
• Digg
• del.icio.us
• Discuss article

Bystander Effect of Introgen's INGN 241 Increases Cancer-Killing Activity in Breast Cancer Cells

Posted on: Thursday, 8 September 2005, 15:00 CDT

SAN DIEGO, Sept. 8 /PRNewswire-FirstCall/ -- Researchers at Introgen Therapeutics, Inc. and their collaborators at The University of Texas M. D. Anderson Cancer Center today reported that MDA-7 protein released from cells treated with INGN 241 can kill nearby, untreated breast cancer cells resulting in additional therapeutic effect. This bystander effect occurs when the therapeutic protein binds to certain receptors on nearby cancer cells. This activity in breast cancer cells is yet another mechanism by which INGN 241 exerts its multiple anti-cancer activities, which also include inhibition of angiogenesis, induction of apoptosis (cell death) and inhibition of cell growth and metastasis. The data were presented today at the 13th International Conference on Gene Therapy of Cancer.

"INGN 241 already has demonstrated multiple potent anti-cancer activities in a variety of clinical and preclinical studies," said Sunil Chada, Ph.D., Introgen's associate vice president, Clinical Research. "The observed bystander effect reported today is significant because it indicates that the number of cancer cells that can be killed by INGN 241 is larger than the number of cells that take up this novel investigational cancer therapy. Combined with the other mechanisms by which INGN 241 kills cancer cells, on its own or in combination with other cancer therapies, these results support the development of INGN 241 in the treatment of cancer."

The studies were conducted in laboratory models of breast cancer. Treatment of human breast cancer cells with INGN 241 arrested cell growth and increased cell killing. Both of these anti-cancer effects correlated with the secretion of MDA-7 protein. The mda-7 gene is the active component of INGN 241. Addition of MDA-7 protein to human breast cancer cells not treated with INGN 241 also resulted in tumor cell death. This suggests that MDA-7 protein secreted by cells treated with INGN 241 can kill nearby untreated cells. Cancer cell killing was blocked by the addition of antibodies against MDA-7 or the MDA-7 receptor, suggesting that this effect is mediated through the binding of MDA-7 to its receptor.

"Cancer is a difficult disease to treat because even a single remaining cancer cell can lead to the relapse or metastasis of cancer," said Dr. Mingzhong Zheng, Research Scientist at Introgen and an author of the study. "The bystander effect observed with secreted MDA-7 protein may be important in the treatment of cancer because it may increase our ability to eliminate as many cancer cells as possible, even cells that have not been directly treated with INGN 241. This may provide a new approach to reducing tumor burden and eliminating or significantly reducing the number of metastatic cancer cells that remain in the body after treatment."

The mda-7 gene was discovered by the laboratory of Dr. Paul B. Fisher, professor of clinical pathology at Columbia University. Introgen holds an exclusive worldwide license for all gene therapy applications from the Corixa Corporation.

Introgen holds a licensing agreement with M. D. Anderson to commercialize products based on licensed technologies, and has the option to license future technologies under sponsored research agreements. The University of Texas System Board of Regents own stock in Introgen. These arrangements are managed in accordance with M. D. Anderson's conflict of interest policies.

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 tumor suppressor therapies to treat a wide range of cancers using non-integrating tumor suppressors, cytokines and genes. 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 for treatment of cancer or other diseases and INGN 241 in the treatment of multiple cancers. 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: For more information on Introgen Therapeutics, or for a menu of archived press releases, please visit Introgen's Website at: http://www.introgen.com/ .

Contact: Introgen Therapeutics, Inc. C. Channing Burke (512) 708 9310 Ext. 322 Email: c.burke@introgen.com

Introgen Therapeutics, Inc.

CONTACT: C. Channing Burke of Introgen Therapeutics, Inc.,+1-512-708-9310 ext. 322, or c.burke@introgen.com

Web site: http://www.introgen.com/

Source: PRNewswire-FirstCall

More News in this Category