At passage 10 (P n-Phenylpiperazine-1-carboxamide were not able to generate tumors in the animals within 24 weeks (Figure 9A). Histological analysis did not reveal any cell or tissue differences other than those expected for subcutaneous tissue, between dermis and muscular tissue (Figure 9B). The animals injected with positive control MDA-MB-231 cells formed malignant tumors after 5 weeks. The tumors presented approximate dimensions of 8.13 mm ?7.02 mm ?5.46 mm. The histological analysis revealed the following features: solid tumor with pleomorphism, mitotic activity and welldelimited tumors (Figure 9C). Moreover, necrosis in the inner area was observed in some PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/9638577 tumors. Animals injected with the other positive control FN052 iPS cellsPaula et al. Stem Cell Research Therapy (2015) 6:Page 11 offormed one clearly identifiable tumor in the locale of the injection after 12 weeks. The tumors presented approximate dimensions of 14.16 mm ?15.86 mm ?8.04 mm (Figure 9D). The tumors were very heterogeneous, and histological analysis revealed tissues from all three germ oncotarget.13387 layers, featuring teratoma. Representative tissue sections stained with hematoxylin and eosin indicated transitional epithelium (endoderm-like tissue; Figure 9E), neural ectoderm (ectoderm-like tissue; Figure 9F) and skeletal muscle (mesoderm-like tissue; Figure 9G).Figure 4 Proliferation kinetics of human adipose tissue-derived stem cells cultured in basal medium supplemented with allogeneic human serum and fetal 3-Fluoro-2-(trifluoromethyl)aniline bovine serum. (A) Mean cumulative population doublings measured and expressed as a function of passage number for allogeneic human serum (aHS; black bars) and fetal bovine serum (FBS; white bars). The results represent the mean ?SEM. Analaysis of variance (ANOVA) with Bonferroni's post-test PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/6967774 was performed. P < 0.05, comparing the condition of basal medium with aHS to basal medium with FBS at all passages and for comparisons between all passages for the condition of basal medium supplemented with aHS. For comparisons between all passages for the condition of basal medium supplemented with FBS: *P < 0.05 for the P1 ?P3 comparison; #P < 0.05 for the P3 ?P5 comparison; +P < 0.05 for the P5 ?P6 comparison; P < 0.05 for the P6 ?P8 comparison. (B) Growth curve assessing the proliferation kinetics of human adipose tissue-derived stem cells.