Navigation Links
Cancer drug effectiveness substantially advanced
Date:4/8/2010

Santa Barbara, Calif., April 8, 2010 Researchers have shown that a peptide (a chain of amino acids) called iRGD helps co-administered drugs penetrate deeply into tumor tissue. The peptide has been shown to substantially increase treatment efficacy against human breast, prostate and pancreatic cancers in mice, achieving the same therapeutic effect as a normal dose with one-third as much of the drug. In a transformative paper published today in the online edition of the journal Science, Erkki Ruoslahti, M.D., Ph.D., distinguished professor at Sanford-Burnham Medical Research Institute and founding member of the UC Santa Barbara-Sanford|Burnham Center for Nanomedicine, Kazuki N. Sugahara, M.D., Ph.D., Tambet Teesalu, Ph.D., and fellow researchers at the Center for Nanomedicine and the Cancer Center of Santa Barbara, announced this significant advance in cancer therapy.

"Drugs generally have difficulty penetrating tumors beyond a few cell diameters from a blood vessel," said Dr. Ruoslahti. "This leaves some tumor cells with a suboptimal dose, increasing the risk of both recurrence and drug resistance. The iRGD peptide solves this problem by activating a transport system in tumors that distributes co-injected drugs into the entire tumor and increases drug accumulation in the tumor."

Dr. Ruoslahti showed in the 1980s that a 3 amino-acid peptide motif (RGDArginine-Glycine-Aspartic Acid) serves as a highly selective identifier of malignant tissue, binding to unique re-ceptors in the vasculature of cancers. The RGD peptide's ability to home to tumors has been used to design new compounds for cancer diagnosis and treatment.

The new variant of RGD (iRGDinternalizing RGD) combines the RGD motif with a tissue penetration element called CendR. Like the earlier RGD peptides, iRGD homes to tumors, but exposure of the CendR motif when the iRGD is enzymatically cleaved activates a transport system through tumor blood vessel walls into the tumor core. In a paper published in Cancer Cell late last year, the research team showed that coupling iRGD to anti-cancer drugs allowed them to penetrate deep into tumors, effectively increasing the activity of the drugs.

The research reported in this latest Science paper adds a new and important twist to the story: The researchers made the unanticipated discovery that anti-cancer drugs do not need to be chemically attached to the iRGD peptide for iRGD to boost their efficacy. Simply co-administering iRGD with a drug enhances the drug's anti-cancer properties. Co-administration could be even more effective at delivering therapeutic agents inside tumors than conjugating the agents with the peptide. This new paradigm means that iRGD has the potential to enhance the efficacy of already approved drugs without creating new chemical entities, which would complicate the path to approval for clinical use.

In addition to being effective against human breast, prostate and pancreatic cancers grown in mice, iRGD can penetrate other tumor types and could possibly be used to treat most, if not all, solid tumors. The iRGD peptide was also shown to enhance the therapeutic effects of multiple types of anti-cancer drugs, including a small molecule drug, a monoclonal antibody and two nanoparticle drugs. Tumors essentially resistant to a particular drug showed good responses when the drug was combined with iRGD, and tumors partially responsive to another drug were eradicated by the combination.

"We are really excited about the potential of iRGD, and I'd like to thank my colleagues, Kazuki Sugahara and Tambet Teesalu in particular, who made this all happen," said Dr. Ruoslahti. "These results with human tumors in mice are very promising, but we still have to demonstrate the value of iRGD in treating cancers in humans."


'/>"/>

Contact: Josh Baxt
jbaxt@sanfordburnham.org
858-795-5236
Sanford-Burnham Medical Research Institute
Source:Eurekalert

Related biology news :

1. Disparities persist in outcomes for African-American women with advanced breast cancer
2. The immune systems guard against cancer
3. Chip checks for oral cancer
4. New discovery is a significant boost to cancer research
5. VARI study could improve treatments for prostate cancer
6. New cancer therapy may fight cardiovascular disease
7. Cancer therapy using unique imaging, delivery system focus of NSF CAREER Award
8. Advances reported in quest for drugs targeting childhood cancer
9. Development of new anti-cancer gene therapy approach using lentiviral vectors
10. Specific lymph node radiotherapy is well-tolerated after surgery in early breast cancer patients
11. New way discovered to predict which breast cancer patients should be treated with anthracyclines
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/27/2017)... CENTRE, N.Y. , March 27, 2017 /PRNewswire-USNewswire/ ... Healthcare Information and Management Systems Society (HIMSS) Analytics ... Outpatient EMR Adoption Model sm . In addition, ... 12% of U.S. hospitals using an electronic medical ... CHS for its high level of EMR usage ...
(Date:3/24/2017)... -- Research and Markets has announced the addition of ... - Industry Forecast to 2025" report to their offering. ... The Global Biometric Vehicle ... around 15.1% over the next decade to reach approximately $1,580 million ... estimates and forecasts for all the given segments on global as ...
(Date:3/23/2017)... Research and Markets has announced the addition of the "Global ... 2025" report to their offering. ... The Global Vehicle Anti-Theft System Market is ... next decade to reach approximately $14.21 billion by 2025. ... all the given segments on global as well as regional levels ...
Breaking Biology News(10 mins):
(Date:10/12/2017)... ... October 12, 2017 , ... BioMedGPS announces expanded coverage of ... newest module, US Hemostats & Sealants. , SmartTRAK’s US Market for Hemostats and ... synthetic sealants and biologic sealants used in surgical applications. BioMedGPS estimates the market ...
(Date:10/11/2017)... ... October 11, 2017 , ... The CRISPR-Cas9 system ... experiments and avoiding the use of exogenous expression plasmids. The simplicity of programming ... systematic gain-of-function studies. , This complement to loss-of-function studies, such as with ...
(Date:10/11/2017)... , Oct. 11, 2017  VMS BioMarketing, a leading provider ... nationwide oncology Clinical Nurse Educator (CNE) network, which will launch ... for communication among health care professionals to enhance the patient ... office staff, and other health care professionals to help women ... cancer. ...
(Date:10/11/2017)... ... October 11, 2017 , ... Singh Biotechnology today announced ... to SBT-100, its novel anti-STAT3 (Signal Transducer and Activator of Transcription 3) B ... to cross the cell membrane and bind intracellular STAT3 and inhibit its function. ...
Breaking Biology Technology: