Characteristics of a rat fibrosarcoma-derived transplantable tumour line (SS) and cultured cell lines (SS-P and SS-A3-1) showing myofibroblastic and histiocytic phenotypes.
A transplantable tumour line (SS) was established in syngeneic rats from a spontaneous fibrosarcoma that had arisen in the submandibular salivary gland of a 24-month-old male F344 rat. A cell line (SS-P) was induced from SS, and a cloned cell line (SS-A3-1) was isolated from SS-P. The primary tumour consisted of oval to spindle-shaped cells arranged in bundles with abundant collagen fibres; ultrastructurally, neoplastic cells exhibited fusiform morphology with prominent rough endoplasmic reticulum. SS tumours showed marked interlacing fascicle and herring-bone growth patterns. SS-P and SS-A3-1 were similar morphologically to each other, consisting of oval, spindle or polygonal cells and occasional multinucleated giant cells. Tumours induced by SS-P and SS-A3-1 were histologically similar to SS tumours. Immunohistochemically, all cells in the primary tumour, SS tumours and tumours induced both by SS-P and SS-A3-1 and by SS-P and SS-A3-1 cultures gave a positive reaction to vimentin. Interestingly, neoplastic cells reacting to ED1 (rat macrophage/histiocyte-specific antibody) and alpha-smooth muscle actin (alpha-SMA) appeared in SS tumours and tumours induced by SS-P and SS-A3-1 and by SS-P and SS-A3-1 cultures. Cells with histiocytic fine structures and myofibroblastic cells with cytoplasmic actin-like microfilaments were also observed by electron microscopy. The present rat fibrosarcoma-derived transplantable tumour line (SS) and cell lines (SS-P and SS-A3-1) might express myofibroblastic and histiocytic phenotypes, probably depending on the surrounding conditions. These cell lines may prove useful for studying the mechanisms of phenotypic plasticity in neoplastic fibroblasts.
Yamate
J
J
Department of Veterinary Pathology, College of Agriculture, Osaka Prefecture University, Japan. yamate@jyui.vet.osakafu-u.ac.jp
Iwaki
M
M
Kumagai
D
D
Tsukamoto
Y
Y
Kuwamura
M
M
Nakatsuji
S
S
Tsunenari
I
I
Kotani
T
T
Sakuma
S
S
D000199:Actins / Q000032:analysis; D000818:Animals; D014408:Biomarkers, Tumor / Q000032:analysis; D002455:Cell Division; D002869:Chromosome Aberrations; D005260:Female; D005347:Fibroblasts / Q000473:pathology*; D005354:Fibrosarcoma / Q000737:chemistry / Q000473:pathology* / Q000648:ultrastructure; D006644:Histiocytes / Q000737:chemistry / Q000473:pathology* / Q000648:ultrastructure; D006651:Histocytochemistry; D007150:Immunohistochemistry; D008297:Male; D008854:Microscopy, Electron; D009132:Muscles / Q000473:pathology; D009368:Neoplasm Transplantation; D051381:Rats; D011916:Rats, Inbred F344; D009418:S100 Proteins / Q000032:analysis; D013365:Submandibular Gland Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000648:ultrastructure; D014407:Tumor Cells, Cultured; D014746:Vimentin / Q000032:analysis
D000199:Actins; D014408:Biomarkers, Tumor; D009418:S100 Proteins; D014746:Vimentin