Cancer

Molecular markers of cancer in cartilaginous fish: immunocytochemical study of PCNA, p‐53, myc and ras expression in neoplastic and hyperplastic tissues from free ranging blue sharks, Prionace glauca (L.)

“…This study was undertaken to detect molecular markers of neoplastic transformation in tissues from sharks and thus provide additional evidence of their susceptibility to neoplastic diseases. We used immunocytochemical procedures to visualize changes in the expression of proliferating cell nuclear antigen (PCNA), and to detect products of the p‐ras , c‐myc and p‐53 genes, all of which are well‐established markers of neoplastic transformation in mammals and in bony fish (Baumann & Okihiro 2000). Previous investigations have documented cross‐reactivity of tissue‐specific antigens from bony fish and their mammalian counterparts as detected by immunocytochemistry (Bunton 1993).…”

“…Subsequently, immunocytochemistry has been used in teleosts to diagnose tissue‐specific antigens in tumours, and to study their alteration of cellular proliferation rates measured as increases in the expression of PCNA (Bunton 1994, 1995, 2000). Recent immunocytochemical studies of neoplasia in fish suggest that some of their tumours express detectable specific mutations in tumour suppressor genes and oncogenes, and can overexpress PCNA (Grizzle & Goodwin 1998; Baumann & Okihiro 2000). Thus, common genetic and epigenetic pathways of neoplastic transformation in cells from mammals and teleosts have been documented (Bunton 2000).…”

“…The immunocytochemical assay for PCNA has been used widely to assess the proliferation status of transformed cells in tumours from vertebrates. PCNA is a DNA polymerase delta auxiliary factor that is synthesized throughout the cell cycle, with the exception of the resting phase (Baumann & Okihiro 2000). PCNA has been detected in numerous cell types in mammalian tissue and recent studies have shown that aquatic species exhibit PCNA‐positive staining in the primary gill filament, alimentary tract epithelium, and in cells from the testes of the medaka, Oryzias latipes (Temminck & Schlegel), guppy, Poecilia reticulata Peters, western mosquitofish, Gambusia affinis (Baird & Girard) (Ortego, Hawkins, Walker, Krol & Benson 1994) and the spiny dogfish shark, Squalus acanthias L. (McClusky 2005).…”

“…The high degree of homology between the tumour suppressor gene p‐53 and oncogenes of the myc and ras families among bony fish and mammals has been shown in several studies (Caron de Fromentel, Pakdel, Chapus, Baney, May & Soussi 1992; Panno & McKeown 1995; Vincent, Jaunet, Galgani, Besselink & Koeman 1995; Krause, Rhodes & Van Beneden 1997; Peck‐Miller, Myers, Collier & Stein 1998; Bhaskaran, May, Rand‐Weaver & Tyler 1999; Franklin, Lee, Köhler & Chipman 2000; Vincent‐Hubert 2000; Liu, Kullman, Bencic, Torten & Hinton 2003). Alterations in the expressions of the above genes in fish tumourigenesis have been widely documented in natural and experimental settings (Vincent, de Boer, Pfohl‐Leszkowicz, Cherrel & Galgani 1998; Baumann & Okihiro 2000; Rotchell, Lee, Chipman & Ostrander 2001; Liu et al. 2003).…”

Assessment of the fish tumor beneficial use impairment in brown bullhead (<i>Ameiurus nebulosus</i>) at selected Great Lakes Areas of Concern

“…Altered foci, particularly basophilic foci, have been postulated to be preneoplastic in some fish species (Hendricks and others, 1984;Hinton and others, 1988;Boorman and others, 1997). While it is not known which altered foci, if any, are preneoplastic in brown bullhead, there is evidence the foci are indicators of contaminant exposure (Baumann and Okihiro, 2000;Blazer and others, 2006;2009 b). Neoplastic lesions include hepatocellular adenoma (benign or noninvasive hepatic neoplasm), which are generally encapsulated and cause compression of surrounding tissue ( fig.…”