Lani
04-25-2006, 09:34 AM
Chemotherapy gel may fight breast cancer and reduce breast deformity [Eureka News Service]
PITTSBURGH- Women who undergo surgery for breast cancer followed by radiation therapy often experience breast deformities that can only be corrected through reconstructive surgery. Researchers at the McGowan Institute for Regenerative Medicine, in collaboration with bioengineers at Carnegie Mellon University, have developed a polymer-based therapy for breast cancer that could serve as an artificial tissue filler after surgery and a clinically effective therapy. Their findings, based on studies with mice, will be presented at 10:15 a.m., Tuesday, April 25 at the World Congress on Tissue Engineering and Regenerative Medicine, April 24 to 27, at the Westin Convention Center in Pittsburgh.
"Although radiation therapy is the standard treatment for breast cancer following surgery, it is expensive, time consuming and increases the cosmetic deformity caused by surgery," said Howard D. Edington, M.D., associate professor of surgery and surgical oncology at the University of Pittsburgh and faculty member at McGowan. "We sought to develop a possible alternative to radiation therapy that would not only release chemotherapy slowly to kill the cancerous cells left behind after surgery but that also would fill in the dimples and sometimes quite significant indentations that are common after breast surgery and radiation."
To test their idea, the researchers encapsulated a common breast cancer chemotherapy drug, doxorubicin, in microspheres, or beads, and then mixed them with a gelatin made of a polymer substance. Mice with breast cancer tumors were treated by inserting the gel under the skin next to the mammary gland. The researchers found that they could successfully control the delivery of chemotherapy over a period of 30 days and that the tumors were completely eradicated compared to a control group of mice that were implanted with the gel insert without chemotherapy.
"Through further research and testing, our goal is to develop this into a clinical treatment for women undergoing breast cancer surgery," said Dr. Edington who also is chief of surgery at Magee-Womens Hospital. "This treatment may help decrease the occurrences of breast deformity. With more studies under our belt, we believe this approach could eventually represent an alternative to breast radiation after surgery."
According to Dr. Edington, clinical trials on women with breast cancer will follow additional laboratory studies. A paper detailing these results will be published in the Journal of Biomedical Materials Research.
ABSTRACT: In vivo anti-tumor effect of a novel drug delivery system for breast conservation (PDF) [World Congress on Tissue Engineering and Regenerative Medicine]
Introduction: Standard therapy for women with early breast cancer is segmental resection (lumpectomy) followed by breast irradiation. However, radiation therapy is expensive and may lead to a significant cosmetic deformity. Local regional delivery of chemotherapy may be an option to reduce local recurrence rates. Doxorubicin, an anthracycline chemotherapeutic, has been used to treat breast cancer. However, doxorubicin is toxic and limited by its cumulative dose-related cardiotoxicity1. Drug delivery systems have been used to locally deliver drugs and reduce systemic levels. We have combined drug delivering microspheres within a hydrogel, resulting in a delivery system that not only delivers the drug, but may represent an aesthetic advantage by maintaining the presurgical breast contour and promoting tissue ingrowth into the surgical defect (tissue engineering).
The objective of this study was to investigate the in vivo anti-tumor effect of doxorubicin released from a biodegradable delivery system. This delivery system would release doxorubicin locally in a controlled manner. We have previously demonstrated the in vitro efficacy of this delivery system2. As such, doxorubicin-encapsulated microspheres were incorporated into gelatin scaffolds, and the constructs were implanted in BALB/c mice inoculated with tumors. The anti-tumor effect and toxicity of the doxorubicin constructs was assessed.
....
Results and Discussion: All of the mice were weighed throughout the experiment, their weight was expressed as a percentage to their initial body weight (Figure 1). A slight decrease in body weight was seen in the animals treated with dox2 constructs. However, none of the mice experienced a decrease greater than 10%, and thus considered tolerable.
The in vivo anti-tumor effect was assessed by measuring the size of the excised tumors. Figure 2 depicts the average tumor volume for each treatment group. A statistically significant difference in the average volume of tumors between mice treated with dox2 constructs and those treated with empty constructs was observed.
All of the mice treated with an empty construct or dox1 construct formed tumors. However, only one mouse out of 5 treated with dox2 constructs showed any signs of tissue growth. We are currently determining whether the growth is tumor or scar tissue.
Conclusions: We have demonstrated the in vivo anti-tumor effect of our novel delivery system. The implanted constructs did not have a detrimental effect on the body weight of the mice. Mice treated with 2 dox constructs showed a significant anti-tumor effect. We are currently assessing the histological results to further confirm our results. The delivery system shows immense promise as an alternative therapy for breast cancer patients following tumor resection.
PITTSBURGH- Women who undergo surgery for breast cancer followed by radiation therapy often experience breast deformities that can only be corrected through reconstructive surgery. Researchers at the McGowan Institute for Regenerative Medicine, in collaboration with bioengineers at Carnegie Mellon University, have developed a polymer-based therapy for breast cancer that could serve as an artificial tissue filler after surgery and a clinically effective therapy. Their findings, based on studies with mice, will be presented at 10:15 a.m., Tuesday, April 25 at the World Congress on Tissue Engineering and Regenerative Medicine, April 24 to 27, at the Westin Convention Center in Pittsburgh.
"Although radiation therapy is the standard treatment for breast cancer following surgery, it is expensive, time consuming and increases the cosmetic deformity caused by surgery," said Howard D. Edington, M.D., associate professor of surgery and surgical oncology at the University of Pittsburgh and faculty member at McGowan. "We sought to develop a possible alternative to radiation therapy that would not only release chemotherapy slowly to kill the cancerous cells left behind after surgery but that also would fill in the dimples and sometimes quite significant indentations that are common after breast surgery and radiation."
To test their idea, the researchers encapsulated a common breast cancer chemotherapy drug, doxorubicin, in microspheres, or beads, and then mixed them with a gelatin made of a polymer substance. Mice with breast cancer tumors were treated by inserting the gel under the skin next to the mammary gland. The researchers found that they could successfully control the delivery of chemotherapy over a period of 30 days and that the tumors were completely eradicated compared to a control group of mice that were implanted with the gel insert without chemotherapy.
"Through further research and testing, our goal is to develop this into a clinical treatment for women undergoing breast cancer surgery," said Dr. Edington who also is chief of surgery at Magee-Womens Hospital. "This treatment may help decrease the occurrences of breast deformity. With more studies under our belt, we believe this approach could eventually represent an alternative to breast radiation after surgery."
According to Dr. Edington, clinical trials on women with breast cancer will follow additional laboratory studies. A paper detailing these results will be published in the Journal of Biomedical Materials Research.
ABSTRACT: In vivo anti-tumor effect of a novel drug delivery system for breast conservation (PDF) [World Congress on Tissue Engineering and Regenerative Medicine]
Introduction: Standard therapy for women with early breast cancer is segmental resection (lumpectomy) followed by breast irradiation. However, radiation therapy is expensive and may lead to a significant cosmetic deformity. Local regional delivery of chemotherapy may be an option to reduce local recurrence rates. Doxorubicin, an anthracycline chemotherapeutic, has been used to treat breast cancer. However, doxorubicin is toxic and limited by its cumulative dose-related cardiotoxicity1. Drug delivery systems have been used to locally deliver drugs and reduce systemic levels. We have combined drug delivering microspheres within a hydrogel, resulting in a delivery system that not only delivers the drug, but may represent an aesthetic advantage by maintaining the presurgical breast contour and promoting tissue ingrowth into the surgical defect (tissue engineering).
The objective of this study was to investigate the in vivo anti-tumor effect of doxorubicin released from a biodegradable delivery system. This delivery system would release doxorubicin locally in a controlled manner. We have previously demonstrated the in vitro efficacy of this delivery system2. As such, doxorubicin-encapsulated microspheres were incorporated into gelatin scaffolds, and the constructs were implanted in BALB/c mice inoculated with tumors. The anti-tumor effect and toxicity of the doxorubicin constructs was assessed.
....
Results and Discussion: All of the mice were weighed throughout the experiment, their weight was expressed as a percentage to their initial body weight (Figure 1). A slight decrease in body weight was seen in the animals treated with dox2 constructs. However, none of the mice experienced a decrease greater than 10%, and thus considered tolerable.
The in vivo anti-tumor effect was assessed by measuring the size of the excised tumors. Figure 2 depicts the average tumor volume for each treatment group. A statistically significant difference in the average volume of tumors between mice treated with dox2 constructs and those treated with empty constructs was observed.
All of the mice treated with an empty construct or dox1 construct formed tumors. However, only one mouse out of 5 treated with dox2 constructs showed any signs of tissue growth. We are currently determining whether the growth is tumor or scar tissue.
Conclusions: We have demonstrated the in vivo anti-tumor effect of our novel delivery system. The implanted constructs did not have a detrimental effect on the body weight of the mice. Mice treated with 2 dox constructs showed a significant anti-tumor effect. We are currently assessing the histological results to further confirm our results. The delivery system shows immense promise as an alternative therapy for breast cancer patients following tumor resection.