No other serum enzymes and proteins were significantly elevated by LCL85. LCL85 suppresses colon carcinoma metastatic potential in an experimental lung metastasis mouse model in vivo To determine the efficacy of LCL85 in suppression of me tastasis in vivo, we used an experimental metastasis mouse model. Colon26 cells, then a highly metastatic colon carcinoma cell line, were injected i. v. to mice. Tumor bearing mice were treated with LCL85 over time. Lung metastasis was then analyzed. LCL85 significantly suppressed colon26 lung metastasis in a dose dependent manner. Although LCL85 Inhibitors,Modulators,Libraries possesses direct anti tumor cytotox icity that might contribute to the observed tumor suppression, it is possible that LCL85 might also sensitize the Inhibitors,Modulators,Libraries tumor cells to apoptosis induction by FasL of host immune cells, particularly CD8 CTLs.

We then dissected tumor bearing lungs and made single cell suspension with collagenase. Staining cells with CD8 and FasL specific mAbs revealed that CD8 T cells in tumor free mice are essentially FasL. In contrast, ap proximately 31% of tumor infiltrating Inhibitors,Modulators,Libraries CD8 T cells are FasL. CD8 cells in tumor free mice are all FasL. Therefore, LCL85 might sensitize colon carcinoma cells to host FasL CTL mediated tumor suppression. LCL85 suppresses spontaneous breast cancer metastasis in vivo To further determine the function of LCL85 in suppres sion of cancer metastasis, we used a complimentary breast cancer lung metastasis mouse model. Murine breast cancer Inhibitors,Modulators,Libraries 4 T1 cells were injected to the mammary fat pad. Tumor bearing mice were treated with LCL85 over time and both primary tumor growth and lung metastasis were examined.

LCL85 significantly suppressed the primary mammary tumor growth in vivo as measured by tumor size and tumor weight. Interestingly, the spontaneous lung metastasis was also significantly sup pressed by LCL85. The observation that LCL85 suppresses spontaneous breast cancer lung me tastasis is significant. However, it is possible that the decreased lung metastasis Inhibitors,Modulators,Libraries was due to the decreased primary tumor growth. To deter mine whether LCL85 directly suppresses spontaneous metastasis, 4 T1 cells were injected to mouse mammary fat pad. Primary tumors were surgically removed 15 days after tumor cell injection. Mice were treated with LCL85 over time after surgery. This procedure thus mimics human breast cancer patient treatment.

Analysis of lungs indicated that LCL85 inhibitor AZD9291 significantly suppresses breast can cer spontaneous lung metastasis. Taken together, our data demonstrated that LCL85 at a subtoxic dose is effective in suppression of colon and breast cancer metastasis. Discussion Ceramide mediates apoptosis through multiple mecha nisms. It has been reported that ceramide mediates Fas receptor clustering, capping and activation to promote Fas mediated apoptosis.