G 1478 or control chow with ad libitum feeding until 90 days of age after which their intestinal tracts were removed and the number of intestinal tumors counted. checkpoint inhibitors AG 1478 reduced polyp number by 45 compared to controls , almost identical to that reported for another reversible EGFR inhibitor EKI 785 under similar experimental conditions , but less than the 87 reduction in tumor number reported for EKB 569 . This establishes the anti tumor efficacy of AG 1478 in ApcMin mice and demonstrates that oral delivery in the diet is an effective route. Chronic exposure to EGFR inhibitors results in mild physiological changes Female wild type B6 mice chronically exposed to small molecule EGFR inhibitors exhibited depressed weight gain over the course of exposure compared to controls .
After 90 days of treatment, EKB 569 treated mice had lost almost 6 of their starting body weight while their respective controls gained checkpoint inhibitors approximately 14 over baseline body weights. Although AG 1478 treated mice and their respective control groups gained weight over the course of the experiment, drug treatment greatly retarded weight gain. Alterations in body weight suggested Ganetespib that EGFR inhibitors may have affected feeding behaviors or energy expenditure, or caused mild toxicity at the drug concentrations used; however, there were no signs of dehydration, lethargy or ataxia in any treatment groups. There were no significant differences in wet heart, liver or kidney weight by treatment group However, EKB 569 treated female mice had increased wet lung weights, which remained significant when normalized for body weight.
Since interstitial lung disease has been reported in a subset of patients treated with the EGFR small molecule inhibitor gefitinib , we used Masson’s Trichrome stain for collagen production and found that EKB 569 treated female mice were indistinguishable from the control group. Similarly, there was no difference in lung inflammation. However, the lungs from EGFR NSCLC inhibitor treated mice did have a slightly higher level of proteinosis than that observed in the lungs from control mice . EGFR inhibition results in altered cardiovascular function due to increased LV apoptosis Chronic dietary exposure to EGFR small molecule inhibitors led to significantly altered cardiac function as assessed by TTE only in female mice, although the severity varied by drug .
Both EGFR inhibitors caused increased left ventricular end diastolic and systolic dimensions and reduced contractility, as measured by percent fractional shortening , compared to baseline values or controls. EKB 569 had the greatest effect on LV wall thickness. Consistent with echocardiographic data, H E Ganetespib stained cross sections taken at the level of the papillary muscle also showed morphological evidence of checkpoint inhibitor LV and septal wall thinning . Because significant alterations were seen in cardiac function with drug treatment, we conducted a histological analysis to investigate pathological endpoints such as cardiomyocyte hypertrophy, fibrosis, and apoptosis. Consistent with heart weight data, there were no significant differences in mean cardiomyocyte area or in gene expression of classic hypertrophy markers in the LV by treatment in female mice .
There were also no significant differences in LV gene expression of selected Erbb family members and ligands . Mild to moderate interstitial and perivascular fibrosis, as demonstrated by Masson’s Ganetespib Trichrome stain, was observed in the LV walls of 25 of EKB 569 and greater than 50 of AG 1478 treated female mice . Milder interstitial fibrosis was also observed in 20 control animals . Less frequent pathological observations included the presence of thrombi and proteinaceous material in the right ventricle and neointimal hyperplasia in the coronary arteries of EGFR inhibitor treated female mice. Interestingly, both inhibitors increased the number of TUNEL positive cardiac cells with apoptotic cells located in the LV walls, LV papillary muscle, and left atria of female mice .
Consistent with TUNEL staining, Ganetespib altered expression of apoptotic genes was observed in the LV of inhibitor treated female mice relative to controls . Expression of the anti apoptotic gene Bcl2l1 was suppressed by approximately 50 , and the pro apoptotic genes Bad and Bax were also altered, albeit not reaching statistical significance. Since earlier evidence demonstrated that EGFR activity is required for normal semilunar valve development , we investigated the effects of chronic exposure to EGFR inhibitors on morphological and histological changes in cardiac valves. Initial results using EKB 569 suggested that reduced EGFR activity might trigger excessive extracellular matrix production and calcification in adult valves. All EKB 569 treated female mice, but less than half of the control mice, had evidence of aortic valve calcification by von Kossa staining . However, all B6 female mice from respective control and AG 1478 groups had some evidence of calcification, suggesting that EGF
Monday, June 17, 2013
Ganetespib checkpoint inhibitor For Beginners
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