Ed with BST-2-suppressed sh413. Ruffled hair, shallow breathing, and prostration
Ed with BST-2-suppressed sh413. Ruffled hair, shallow breathing, and prostration were observed in shControl-implanted mice but not in sh413-implanted mice (Figure 4A). Furthermore, mice implanted with BST2-expressing shControl 4T1 cells developed malignant ascites (Figure 4B, middle panel) and severe splenomegaly (Figure 4C, middle panel, inset). Remarkably, 14 out of 15 mice implanted with BST-2-suppressed 4T1 cells (sh413) were spared of ascites (Figure 4B, compare left and rightBecause human breast cancer patients bearing tumors with high BST-2 mRNA have lower survival, we directly evaluated the role of BST-2 expression in cancer cells on the survival of tumor-bearing mice. Kaplan-Meier survival curve analysis reveals that mice implanted with BST-2suppressed sh413 4T1 or E0771 cells have a statistically significant prolongation in survival compared with BST-2expressing shControl-implanted mice (Figure 4D (4T1) and Figure S4C (E0771) in Additional file 4). Improvement in survival was more pronounced in the 4T1 model because all PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/28549975 (n = 15) mice implanted with 4T1 shControl cells died on average 25 days post implantation. Surprisingly, 14 out of 15 mice implanted with 4T1 sh413 cells survived and were euthanized at the end of the experiment (day 45). One out of 15 4T1 sh413-implanted mice was sacrificed on day 37 post implantation due to EPZ004777 cost tumor-associated morbidity (Figure 4D). The OS and AUC for 4T1 shControl-bearing mice were 28 days and 2,345 compared to sh413-bearing mice with undefined OS and 3,900 AUC. Additionally, mice implanted with E0771 shControl cells died at approximately 16 days post implantation compared to their E0771 sh413 cells-implanted counterparts that averaged 23 days post implantation (Figure S4C in Additional file 4). The OS and AUC of E0771 shControl mice were 16 days and 1,965 respectively, while E0771 sh413-implanted mice have 23 days OS and 2,679 AUC. Together with the human survival data presented in Figure 1G, our results support the premise that BST-Mahauad-Fernandez et al. Breast Cancer Research (2014) 16:Page 10 ofFigure 4 BST-2 expression in cancer cells is a strong prognostic factor for morbidity and overall survival. (A) Clinical score plot of mice implanted with 4T1 BST-2-expressing shControl and BST-2-suppressed sh413 cells. Clinical signs were scored as follows: 0 = no abnormal clinical signs; 1 = ruffled fur but lively; 2 = ruffled fur, activity level slowing, sick; 3 = ruffled fur, eyes squeezed shut, hunched, hardly moving, very sick; 4 = moribund; 5 = dead [23]. (B) Representative gross images of the abdomen of uninjected (left), shControl-implanted (middle), and sh413-implanted (right) mice. Arrow points to metastatic ascites (middle panel). (C) Representative splenic gross images (top panel insets) and spleen histology at low magnification (4X, top panel). Boxed regions are shown at higher magnification (60X) from uninjected (left panel), shControl (middle panel), and sh413 (right panel) injected BALB/c mice (bottom panels). There was marked expansion of red pulp due to granulocytic hyperplasia in the shControl spleen with slightly increased number of granulocytes in the red pulp of the sh413 spleen. Scale bar = 5 mm. (D) Kaplan-Meier survival plot of mice implanted with BST-2-expressing shControl and BST-2-suppressed sh413 4T1 cells. Numbers are P values and error bars represent standard deviations. Median overall survival (OS) time and the area under the curve (AUC) are shown for each group.ex.