Fig. 2: Ectopic TYMS (hTS) enhances tumor infiltration and increases incidence of histiocytic sarcoma in hTS/Ink4a/Arf −/− mice.
From: TYMS promotes genomic instability and tumor progression in Ink4a/Arf null background
A Histiocytic sarcoma infiltrating multiple organs in hTS/Ink4a/Arf −/− mice. Macroscopic spleen (mouse ID 5219), lymph nodes (mouse ID 5213), liver (mouse ID 5219), kidney (mouse ID 5242), and pancreas (mouse ID 5172) images, histological evaluation by H&E stained FFPE sections and immunostaining for Mac-2 and CD45R are shown at survival endpoint. Mac-2-positive and CD45R-negative staining discriminates histiocytic sarcoma cells from lymphoma in spleen and lymph nodes. Scale bar represents 80 μm in spleen and 50 μm in sections from other organs. B Histological analysis showing H&E stained FFPE sections of spleen and kidney from mice diagnosed with histiocytic sarcoma. Upper panel, erythrophagocytosis (yellow arrowhead) in splenic macrophages. Lower panel, hyaline droplet nephropathy (black arrowhead) in kidney infiltrated with histiocytic sarcoma. Scale bar represents 50 μm. C hTS mRNA expression detected by RT-PCR analysis in spleens isolated from hTS/Ink4a/Arf −/− and Ink4a/Arf −/− mice affected with lymphoma (Lym) or histiocytic sarcoma (HS) as compared to normal (N) spleen. Actin is used as loading control. D hTS mRNA is upregulated in spleens and lymph nodes of tumor bearing hTS/Ink4a/Arf −/− as compared to Ink4a/Arf −/− mice. RT-qPCR showing relative TS mRNA levels in Ink4a/Arf −/− (n = 8) and hTS/Ink4a/Arf −/− (n = 11) spleens (left panel, *P = 0.0264) and Ink4a/Arf −/− (n = 4) and hTS/Ink4a/Arf −/− (n = 5) lymph nodes (right panel, *P = 0.0180). Values represent mean ± SD. E hTS overexpression increases ratio of splenic cells in S-phase. Violin plots showing the proportion of BrdU+ cells in splenic single cell suspensions from 5.9 months old mice IP injected with 1 mg of BrdU 4 h before sacrifice. Control (FVB/129/Sv, n = 4), Ink4a/Arf −/− (n = 8) and hTS/Ink4a/Arf −/− (n = 8) mice with normal size (N) and enlarged spleen (E) are shown. Values represent median ± quartiles. * P = 0.0152 by Mann-Whitney test. F Proportion of cells (in %) in G0/G1, S and G2/M phases of cell cycle for control background (FVB/129/Sv, n = 4), Ink4a/Arf −/− (n = 6) and hTS/Ink4a/Arf −/− (n = 6) mice with normal spleen. Values represent mean ± SD. * P = 0.0152 by Mann-Whitney test.
