Expression of class I major histocompatibility antigens switched off by highly oncogenic adenovirus 12 in transformed rat cells

Abstract

Rat cells transformed by the highly oncogenic adenovirus 12 lack at least two cellular proteins which are present in cells transformed by the non-oncogenic adenovirus 5 and in untransformed cells. One protein has been identified as the heavy chain of the rat class I major histocompatibility complex. This finding may explain the difference in oncogenicity between adenoviral species.

N-myc amplification causes down-modulation of MHC class I antigen expression in neuroblastoma

“…Modulation of MHC class I antigen expression was previously shown to be a property of the adenovirus type 12 Ela region (Schrier et al, 1983) which encodes gene products known to be involved in trams-regulation of gene expression (Berk et al, 1979;Nevins, 1981). There are a number of similarities between the myc-and Ela genes, including a nuclear localization of their gene products and an ability of each to cooperate with ras oncogenes in the transformation of primary cells (Yee et al, 1983;Land et al, 1983;Ruley, 1983;Persson and Leder, 1984).…”

“…We speculated that a connection might exist between these two separate sets of observations; namely, that the low expression of MHC class I antigens in these two types of tumors could be caused by the high expression of the myc genes in these cells. This speculation was also inspired by earlier work that showed that expression of an adenovirus Ela oncogene could result in decrease of MHC class I antigen expression (Schrier et al, 1983).…”

“…Northern Blot Analysis RNA isolation and Northern blot analysis were performed as described by Schrier et al (1983). To eliminate influences of growth rate and cell cycle on the expression of the genes studied, RNA was isolated from exponentially growing cells in all cases.…”

A human DNA segment with properties of the gene that predisposes to retinoblastoma and osteosarcoma

“…Methods. Total cytoplasmic RNA was isolated using the Nonidet-P-40 extraction technique, resolved by electrophoresis through a 1% agarose-formaldehyde gel, and transferred onto nitrocellulose as described by Schrier et al 33. Radiolabelling of probes was performed using the random-primer method'''.…”

Differential expression of H-2Dd and H-2Ld histocompatibility antigens.

“…Antigenic modulation experiments demonstrate that, when the TL antigen is removed from the cell surface, the levels of H-2D increase but the surface levels of H-2K remain the same (24,25). More recently, it has been shown that adenovirus 12 infections apparently block the synthesis of class I antigens in infected cells (26) and that SV-40-transformed cells may express a new TL-Qa-like transcript (27). Thus, it is important and useful to define the regulation of class I antigen expression and what factors determine the relative amounts of various class I antigens.…”