Article on Cardiotoxicity

[Joe]

Normally I would just place a link but I feel this article is Important !!

Newer Breast Cancer Drug May Protect Heart, Study Suggests
Science Daily — By uncovering how one breast cancer drug protects the heart and another does not, "It is important to be clear that we are reporting findings from pre-clinical experiments, so while they suggest a difference between these two agents, it would be over-interpreting the study to conclude that women taking trastuzumab should consider any treatment change," Spector said. "However, it may be important to conduct well-controlled clinical trials to answer this question."
In addition to its association with breast cancer, HER2 is also essential for the early development and later sustenance of heart muscle cells. It appears that trastuzumab's mechanism for blocking HER2 is different.
"We found that lapatinib activates a critical pathway that protects heart cells from 'committing suicide' as a result of stress," Spector continued. "Heart muscle cells require a tremendous amount of energy to function properly and are therefore extremely sensitive to energy deprivation as a consequence of reduced oxygen or nutrient supply. In addition, heart muscle cells appear to be sensitive to the death promoting effects of inflammation.
"Our experiments in isolated human heart muscle cells indicate that lapatinib activates a pathway that protects cardiac muscle cells from the death-promoting effects of mediators of inflammation, which are activated in cancer patients, particularly those who have received chemotherapies that damage heart tissue," Spector said. "In contrast, trastuzumab does not activate this protective pathway."
With clinical trials currently investigating the combination of lapatinib with trastuzumab, there is a possibility that the effects of lapatinib in cardiac muscle cells might protect the heart against potential toxicity associated with trastuzumab, Spector added.
More broadly, Spector said that these findings of how lapatinib bestows cardiovascular protection during times of stress -- whether from chemotherapy or heart muscle cells deprived of oxygen during a heart attack -- could be used in other situations.
"Using this system, we could theoretically screen drugs that are in the development phase to see what their effects may be on heart muscle cells," Spector said. "We may be able to select the drug candidates that have the fewest cardiovascular side effects and theoretically would be safer for patients. This way, we could find out about some of these potential problems long before the drugs even make it to market."
Additionally, Spector said there is the potential for the development of similar drugs that can be used as protective agents in situations where the heart is stressed for periods of time, such as during heart attacks, coronary artery bypass surgery or angioplasty. Such a drug could even be used to preserve cardiac function in hearts being harvested for transplant, he said.
The study was supported in part by the Dukelace. The results of the study appear early online in the journal Proceedings of the National Academy of Science.
Other members of the team were Wenle Xia, Duke; Yosef Yarden and Rony Seger, Weizman Institute, Rehovot, Israel; Bradley Smith, Cell Signaling Technologies, Beverly, Mass.; and Ljuba Lyass, Patricia Trusk, Karen Pry, Jason Hill and Sarah Bacus, Targeted Molecular Diagnostics, Westmont, Ill.
Note: This story has been adapted