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[CANCER RESEARCH 52, 2995-2998, May 15, 1992] Advances in Brief Selective Mutation of Codons 204 and 213 of the p53 Gene in Rat Tumors Induced by Alkylating W-Nitroso Compounds' Hiroko Ohgaki, Gordon C. Hard, Norio Hirota, Akihiko Maekawa, Michihito Takahashi, and Paul Kleihues2 Institute of Neuropathology, University of Zurich, CH-8091 Zurich, Switzerland ¡H.O., P. K.¡;American Health Foundation, I'alhalla, New York 10595 [G. C. H.]; Department of Pathology, Jichi Medical School, Kawachi-gun, Tochigi 329-04 Japan [N. H.]; Department of Pathology, Sasaki Institute, Chiyoda-ku, Tokyo 101, Japan [A. M.I; and Division of Pathology, National Institute of Health Sciences, Setagaya-ku, Tokyo 158, Japan ¡M.T.] Abstract Materials Kidney and esophageal tumors induced by alkylating /V-nitroso com pounds in rats contain a high incidence (75-100%) of G -> A transition mutations in the p53 gene. These are almost selectively (89%) located in the tirsi base of codon 204 and the second base of 213, leading to amino acid substitutions Glu -»Lys and Arg -»Gin, respectively. In contrast to human neoplasms, a considerable fraction of rat kidney and esophageal tumors carries multiple p53 mutations. All nephroblastomas induced by transplacental exposure to /V-nitrosoethylurea and 56% of esophageal tumors induced by /V-nitrosomethylurea showed double mutations in codons 204 and 213 of exon 6. The selective targeting of p53 codons by alkylating nitrosamines may provide a basis for molecular epidemiológi ca! studies on this class of chemical carcinogens. Induction of Tumors. Renal mesenchymal tumors were induced in Charles River Wistar rats treated at 5 weeks of age with a single i.p. 40 mg/kg dose of NDMA' (8). Carcinomas (epithelial tumors originating Introduction The pattern of point mutations in the p53 tumor suppressor gene varies considerably in human neoplasms and appears to be related to organ site. G:C to A:T transitions predominate in colon, brain, and lymphoid malignancies, whereas G:C to T:A transversions are most frequent in lung and liver cancers (1). In addition, specific etiological agents may produce typical mutational hotspots. This was first shown for hepatocellular carci nomas from high-incidence areas in South Africa and China, which in 30-40% contain G —¿Â» T transversion in codon 249 (2, 3). This mutation is assumed to result from the interaction of aflatoxin B, with cellular DNA and is not observed in hepato cellular carcinomas from patients with hepatitis B virus infec tion (4). UV light typically induces pyrimidine dimers in skin DNA, and a recent report by Brash et al. (5) showed that squamous cell carcinomas of the skin contain in more than onehalf of cases CC to TT mutations, i.e., double-base changes that are likely to be due to miscoding by UV light-induced thymine dimers. /V-nitroso compounds constitute a group of powerful chemical carcinogens which in experimental animals induce a high incidence of tumors with a remarkable degree of organ specificity (6). Although /V-nitroso compounds have been implicated as contributors to the overall human tumor load, it has proven difficult to identify human neoplasms specifically induced by nitrosamines (7). We have, therefore, analyzed a variety of tumors induced by /V-nitroso compounds in rats and found a high incidence ofp53 mutation, clustered in two codons of exon 6. Received 2/20/92; accepted 4/14/92. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact. 1Supported by grants from the Swiss National Science Foundation. 2To whom requests for reprints should be addressed, at Department Pathol ogie, UniversitätZurich, Schmelzbergstraße 12, 8091 Zurich, Switzerland. and Methods from renal tubles) were induced by the same treatment regimen, except that the dose was 30 mg NDMA/kg, and the age of the rats at treatment was 9-10 weeks (8). Nephroblastomas were induced in Nb hooded rats by a single i.p. (transplacental) exposure to NEU on day 18 of gestation at a dose of 60 mg/kg body weight (9). Spontaneous nephroblastomas from a breeding colony of inbred WAB/Not rats were also examined. These tumors occurred in 0.5% of breeders surviving up to 2 years of age, representing 40% of the total spontaneous tumors in this rat strain (10). Esophageal papillomas and carcinomas were induced in F344 rats by exposure to NMD in the drinking water (200 ppm) for 42 weeks (11). Adenocarcinomas in the glandular stomach were induced in F344 rats by NMU in the drinking water (200 ppm; 15 weeks) (12), by intragastric (gavage) doses of NMU (4 mg/kg each), or in newborn Brown Norway rats by a single dose of NMU (200 mg/kg body weight). Oligodendrogliomas were induced in fetal brain transplants by two doses of NEU (50 mg/kg each), using adult F344 rats as recipients (13). Single-Strand Conformation Polymorphism Analysis. DNA was ex tracted from paraffin sections by the procedure described by Shibata et al. (14) with slight modifications as follows. After comparison with serial sections stained with hematoxylin and eosin, tumors were scraped off the histológica!slide. Samples were deparaffinized with xylene and washed with absolute ethanol. Dried samples were treated with 500 Mg/ ml of proteinase K (Boehringer Mannheim GmbH, Mannheim, Ger many) in 40-80 n\ of digestion buffer (50 mivi Tris, pH 8.5: 1 HIM EDTA; and 0.5% Tween 20) at 55°Cfor 3 h. After inactivation of proteinase K by heating at 95°Cfor 10 min, samples were kept at -20°Cuntil PCR reaction. Pairs of 20-mer oligonucleotide primers corresponding to exons 58 of p53 gene were synthesized on a model 391 PCR-MATE DNA synthesizer (Applied Biosystems, Inc.). The sequences of PCR primers were 5'-ACTCAATTTCCCTCAATAAG and 5'-CACCATCAGAGCACGCTCA for exon 5, S'-GGCCTGGCTCCTCCCCAACA and 5'-GGTGGCTCATACGGTACCAC for exon 6, 5'-GTCGGCTCCGACTATACCAC and 5'-GGAGTCTTCCAGCGTGATGA for exon 7, and 5'-TGGGAATCTTCTGGGACGGG and 5'-TCTCTTTGCACTCCCTGGGG for exon 8. For prescreening the samples for mutations in thep5^ gene, PCR-single-strand conformation polymorphism analy sis was performed according to a slight modification of the method of Onta et al. (15). Briefly, PCR was performed with 2 /jl of DNA solution, 2.5 pmol of each primer, 50 /JM of deoxynucleotide triphosphates, 1 ^Ci of [a-32P)dCTP (Amersham; specific activity, 3000 Ci/mmol). 10 mM Tris (pH 8.8), 50 mM KCI, 1 mM MgCl2, and 0.5 units Taq polymerase (Perkin-Elmer Cetus) in a final volume of 10 fi\. After adding 10 ßlof mineral oil (Sigma), 40 cycles of denaturation (95°C) for 50 s, annealing (58°Cfor exons 5, 62°Cfor exon 6, 6PC for exon 7, and 65°Cfor exon 8) for 50 s, and extension (72°C)for 70 s were performed using an automated DNA thermal cycler (Perkin-Elmer Cetus). 'The abbreviations used are: NDMA. /V-nitrosodimethylamine; NEU, Nnitrosoethylurea; NMU, jV-nitrosomethylurea; PCR. polymerase chain reaction. 2995 Downloaded from cancerres.aacrjournals.org on June 18, 2017. © 1992 American Association for Cancer Research. pS3 MUTATIONS IN NITROSAMINE-INDUCED The reaction mixture (1.5 M') was mixed with 2 M' of 0.1 M NaOH and 9 »/I of sequencing stop solution (USB). Samples were heated at 95°Cfor 10 min and immediately loaded onto a 6% polyacrylamide nondenaturing gel containing 7.5% glycerol. Gels were run at 7 W for 13-15 h at room temperature. Gels were dried at 80°C,autoradiography was performed with an intensifying screen for 5-48 h, and the pattern of single-stranded DNA was checked for differences. Direct DNA Sequencing of PCR Products. For exon 6, all samples were analyzed by direct sequencing of PCR products. For exons 5, 7, and 8, direct sequencing was only carried out on samples which had scored positive in single-stranded conformation polymorphism analy sis. PCR was performed in a total volume of 80 ^1, as described above. After amplification, 70 M'of the PCR reaction mixture were separated on a 6% polyacrylamide gel. Amplified bands were cut out; eluted in 0.5 M ammonium acetate, and 1 mM EDTA at 37°Covernight, and precipitated with ethanol. Dried DNA was resuspended in 15 ^1 of TE buffer ( 10 mM Tris-HCl, l mM EDTA, pH 8.0). Sanger dideoxynucleotide sequencing was performed using [«-'2P]dCTP and amplification primers. The template-primer mixture (4 ^1 DNA and 10 pmol primer) was heated at 95°Cfor 5 min and immediately placed in liquid nitrogen. An aliquot containing 20 mM Tris-HCI (pH 7.5), 10 mM MgCl2, 25 mM NaCl, 0.1 M dithiothreitol, 10% dimethyl sulfoxide, and 5 nCi [a-32P]dCTP was added to each of the four termination mixtures and incubated at 37°Cfor 10 min with 2 units of Sequenase, version 2.0 (USB). Samples were mixed with 4 ^1 stop solution, heated at 80°C for 2 min, and immediately loaded onto a 6% polyacrylamide/7 M urea gel. Gels were fixed with 10% acetic acid and 10% methanol, dried, and autoradiographed for 5 h to 3 days. When mutations were detected, they were further confirmed by sequencing the opposite strand. In each reaction, normal rat kidney DNA was concurrently amplified and sequenced as a negative control. Results Independent of the histopathologic tumor type and mode of induction, all rat kidney tumors investigated contained a high incidence (75-100%) of p53 mutations (Table 1). These were heavily clustered in codons 204 and 213 of exon 6. Often, both exons were mutated in the same neoplasm. This was most prominent in nephroblastomas induced by transplacental ex posure to NEU, all of which contained G —¿Â» A transitions in the first base of codon 204 and in the second base of 213, leading to amino acid substitutions Glu —¿* Lys and Arg —¿Â» Gin, TUMORS respectively. A loss of the normal alÃ-elewas observed in only one renal mesenchymal tumor (Fig. 1). Esophageal papillomas and carcinomas induced by NMU also contained a high inci dence of/753 point mutations in the same two hotspots of exon 6 (Table 1). In both renal and esophageal tumors, mutations other than in exon 6 were rare (11%); among these, G -»A transitions were most frequent (Table 1). Glandular stomach carcinomas induced by NMU and oligodendrogliomas induced by NEU did not contain miscoding p53 point mutations. One stomach carcinoma was found to have a mutation in exon 5 (codon 144), but this was nonmiscoding (CAG —¿Â» CAA; Glu —¿Â» Glu). Discussion DNA sequence analyses were carried out on a variety of tumors induced in rats by methylating or ethylating A'-nitroso compounds, using formalin-fixed, paraffin-embedded tissue samples (Fig. 1). We found a high incidence of miscoding p53 mutations (75-100%) in tumors of the kidney and esophagus but not in neoplasms induced by the same carcinogens in stomach and brain. This suggests that the involvement of p53 inactivation during carcinogenesis occurs with a high degree of tissue specificity. It has previously been shown that NEUinduced gliomas of the central nervous system do not carry ras mutations (16), and when we analyzed NMU-induced glandular stomach carcinomas, we were also unable to detect mutations in the H- and K-ras genes. In contrast, tumors which in the present study were found to carry p53 mutations are also known to have a high incidence of K-ras (kidney) and H-ras (esophagus) mutations (17, 18). It thus appears that in some tissues these transformation-associated genes cooperate in malignant trans formation (19). The simultaneous occurrence of p53 and ras mutations has also been observed in human colorectal cancer (20, 21) but does not seem to apply to all tissues. In studies on human esophageal carcinomas from high-incidence areas, p53 base substitutions were found in 44% of neoplasms, while ras mutations were completely absent (22). Regarding the location ofp53 mutations, the results obtained were unexpected in two respects. Rather than being randomly Table 1 p53 point mutations in rat tumors induced by N-nitroso compounds Mutations in codon 204 (GAG -»AAG) and codon 213 (CGC —¿Â» CAG) cause amino acid substitutions (Glu —¿> Lys and Arg —¿â€¢ Gin, respectively. Point mutations other than in exon 6 are as described in the table footnotes. CarcinogenKidneyCarcinoma Tumor Tumors with or mor p53mutations7/8 5\"1*0001'0AAT; NDMAMesenchymal NDMANephroblastoma tumor NEUNephroblastoma SpontaneousEsophagusCarcinoma/papilloma (88%)6/8 (75%)8/8(100%)8/12(75%)7/9 NMUGlandular (78%)1/12(8%)0/7 Exon 6 2131& (88%)4 (13%)3 (13%)2 (50%)8(100%)9 (38%)8(100%)4 (25%)8(100%)4 (75%)6 (33%)5 (56%)00Codons204 (56%)00Exon (67%)00Codon2131 stomachCarcinoma NMUBrainOligodendroglioma NEU° Thr.* Codon 140, ACA -»ACG; Thr -» Tyr.' Codon 135, TGC -. TAC; Cys -. Ile.' Codon 274, GTT —¿ ATT; Val -. Cys.' Codon 238, TGC —¿ TGT; Cys —¿ Tyr.f Codon 238, TGC —¿ TAC; Cys —¿ codon'Codon Codon 243, TGC -»TAC; Cys -•Tyr; and 144, CAG —¿ CAA; Glu —¿ Glu.one (33%)5 80 7 Exon 00 Ie1" 01' 0y o0 00 (0%)239, 0 » Asn.Codon2047 AAC —¿cExonAsn —¿ 2996 Downloaded from cancerres.aacrjournals.org on June 18, 2017. © 1992 American Association for Cancer Research. pS3 MUTATIONS ACGT ACGT ACGT IN NITROSAMINE-INDUCED TUMORS suggests that O 6-alkyldeoxyguanosines are responsible for these mutations. There is increasing evidence that chemical carcinogens or their ultimate reactive metabolites cause specific base substitu tions in oncogenes and tumor suppressor genes (2, 3, 29-31). Our observation of the same mutational hotspots in tumors of two different tissues (kidney and esophagus) and in three hiscodon G tologically different types of kidney tumors (carcinomas, mes 213 ° enchymal tumors, and nephroblastomas) suggests a selective targeting of codons 204 and 213 in neoplasms induced by alkylating /V-nitroso compounds in rats. Identification of such selective mutations in human neoplasms would allow an esti mation of the actual contribution of carcinogenic /V-nitroso compounds to the overall human tumor load. However, this is the first report on p53 mutations in rats, and it cannot be excluded that mutations at these sites predominate because they lead to a species-specific growth advantage of initiated cells, irrespective of the chemical nature of the inducing agent. Also, site-specific DNA repair deficiency may contribute to the selec codon tive mutations of codons 204 and 213 (28). To resolve this 204 G A question, analyses of a wide range of chemically induced animal tumors will be necessary. However, ¡tmay be worthwhile to analyse exon 6 of p53 in WBC (32) and in second primary malignancies of patients who underwent chemotherapy with methylating (procarbazine, dacarbazine, streptozotocin) or Nephroblastoma chloroethylating[l,3-bis(2-chloroethyl)-l-nitrosoureaand l-(2Normal kidney Renal mesenchymal chloroethyl)-3-cyclohexyl-1 -nitrosourea] agents. tumor It is noteworthy that spontaneous nephroblastomas in WAB/ Fig. 1. DNA sequencing autoradiographs of the rat p53 gene (exon 6) in the region of codons 202 to 217. The renal mesenchymal tumors induced by NDMA Not rats showed p53 point mutations similar to, but less fre contain a transition mutation (GAG —¿Â» AAG) in codon 204, the normal alÃ-ele quently than, neophroblastomas induced by NEU (Table 1). being lost. The nephroblastoma transplacentally induced by NEU shows the same type of mutation in codons 204 (GAG -> AAG) and 213 (CGG —¿ CAG), but the The pathogenesis of spontaneous nephroblastomas has not been normal alÃ-elesare still detectable. fully elucidated (10). Since their incidence is very low (0.5% of breeders surviving up to 2 years), it is unlikely that these neoplasms are due to oncogenic viruses or genetic predisposi distributed over exons 5 to 8, mutations were heavily (89%) tion. Our findings suggest rather that nephroblastomas in clustered in exon 6, and within this exon they selectively af WAB/Not rats are not truly spontaneous but may result from fected codons 204 and 213, leading to amino acid substitutions low-level dietary exposure to environmental /V-nitroso com Glu —¿Â» Lys and Arg —¿> Gin, respectively (Table 1). Point pounds or related carcinogens. mutations in codon 204 have not previously been reported in It has been suggested that the biological properties of mutant any human or animal neoplasm. Codon 213, on the other hand, p53 proteins depend on the site of point mutations. Base is a fairly frequent site for p53 substitution mutations in a substitutions at codons 151, 247, and 273 exert a dominant variety of human neoplasms (1, 23). Furthermore, the third negative effect on the phenotype of cotranslated wild-type hu base of codon 213 shows an approximately 2-11% background man p53, driving the latter into the mutant phenotype form, level of CGA -»CGG (Arg -»Arg) polymorphism (24-26). In whereas the p53 protein encoded by a mutated codon 248, i.e., the rat, this mutation creates a typical intron-exon splicing the germ-line mutation underlying the Li-Fraumeni syndrome acceptor sequence. Another unexpected finding was the simul (33, 34), does not show this effect (35). Studies are under way taneous presence in renal (42%) and esophageal tumors (56%) to determine the effects of point mutations at codons 204 and of mutations in both hotspot codons. This was particularly 213 of the ratp53 gene and their possible relationship to organevident in nephroblastomas transplacentally induced in rats by specific malignant transformation. NEU (9). All eight tumors analyzed contained mutations in Human tumors frequently exhibit either a loss of both alÃ-eles both codons 204 and 213, in addition to a G —¿Â» A transition of the p53 gene, the loss of one p53 alÃ-elewith an associated mutation in codon 12 of the K-ras gene (17). It remains to be point mutation, insertion or deletion of the remaining alÃ-ele,or clarified whether these double mutations are present in the an inactivation of thep53 gene in one alÃ-elebut a normal (wildsame tumor cell population or whether there are different type) sequence in the other. In the present study, sequencing neoplastic cell types containing point mutations at either codon gels showed consistently weaker signals for the mutated base 204 or 213. In human neoplasms, double mutations appear to when compared to the corresponding normal (wild-type) se be a very rare event (26, 27). quence (Fig. 1). This may be due to the fact that only a fraction It has been established that 0-alkylated bases are the major of tumor cells carry the mutation. A loss of the normal alÃ-ele promutagenic DNA lesions produced by simple alkylating N- was observed in only one renal mesenchymal tumor (Fig. 1), nitroso compounds. The pathway for production of point mu but Southern blot analyses with highly polymorphic markers tations by O 6-methyI- and O "-ethyldeoxyguanosine is mispairmay reveal a higher incidence of allelic loss. ing during DNA replication with deoxythymidine (28). Our In conclusion, this study shows that renal and esophageal tumors induced by carcinogenic /V-nitroso compounds in rats finding that most base substitutions are G —¿Â» A transitions 2997 Downloaded from cancerres.aacrjournals.org on June 18, 2017. © 1992 American Association for Cancer Research. p53 MUTATIONS IN NITROSAMINE-INDUCED contain an unusually high incidence of p53 mutations which are clustered in codons 204 and 213. Unlike human neoplasms, a high proportion of tumors contain double mutations in both hotspot codons. References 1. Hollstein. M. C., Sidransky, D., Vogelstein, B., and Harris, C. C. p53 mutations in human cancers. Science (Washington DC), 253:49-53, 1991. 2. Hsu, I. C., Metcalf, R. A.. Sun, T., Welsh, J. A., Wang, N. J., and Harris, C. C. Mutational hotspot in thèp53 gene in human hepatocellular carcino mas. Nature (Lond.), 350: 427-428. 1991. 3. Bressac. B., Kew, M., Wands, J., and Ozturk, M. Selective G to T mutations of p53 gene in hepatocellular carcinoma from southern Africa. Nature (Lond.), 350: 429-431, 1991. 4. Hayward, N. K., Walker, G. J., Graham, W.. and Cooksley, E. Hepatocellular carcinoma mutation. Nature (Lond.), 352: 764, 1991. 5. Brash, D. E., Rudolph, J. A., Simon, J. A., Lin, A., McKenna, G. J., Baden, H. P., Halperin, A. J., and Ponten. J. A role for sunlight in skin cancer: UVinduced p53 mutations in squamous cell carcinoma. Proc. Nati. Acad. Sci. USA,««:10124-10128, 1991. 6. Preussman, R., and Stewart. B. W. yV-Nitroso carcinogens. In: C. E. Searle (ed.). Chemical Carcinogens, ACS Symposium Series 182, pp. 643-828. Washington. DC: American Chemical Society, 1984. 7. Bartsch, H., O'Neill, 1. K., and Schulte-Hermann. R. (eds.). Relevance of NNitroso Compounds to Human Cancer: Exposures and Mechanisms, IARC Scientific Publication no. 84. Lyon: International Agency for Research on Cancer, 1987. 8. Hard, G. C. Experimental models for the sequential analysis of chemicallyinduced renal carcinogenesis. Toxicol. Pathol., 14: 112-122, 1986. 9. Hard, G. C. Differential renal tumor response to /V-ethylnitrosourea and dimethylnilrosamine in the Nb rat: basis for a new rodent model of nephroblastoma. Carcinogenesis (Lond.), 6: 1551-1558. 1985. 10. Middle, J. G., Robinson, G., and Embleton, M. J. Naturally arising tumors of the inbred WAB/Not rat strain. I. Classification, age, sex distribution, and transplantation behavior. J. Nati. Cancer Inst.. 67:629-636, 1981. 11. Maekawa, A., Matsuoka, C., Onodera, H., Tanigawa, H., Furuta, K., Ogiu, T., Mitsumori, K., and Hayashi, Y. Organ-specific carcinogenicity of Nmethyl-/V-nitrosourea in F344 and ACI/N rats. J. Cancer Res. Clin. Oncol., 109: 178-182, 1985. 12. Fujita, M., Ishii, T., Tsukahara, Y., Shimozuma, K.. Nakano, Y., Taguchi, T., and Hirota, N. Establishment of the optimum conditions for induction of stomach carcinoma in rats by oral administration of /V-methyl-jV-nitrosourea. J. Toxicol. Pathol., 2: 27-32, 1989. 13. Burger, P. C., Shibata, T., Aguzzi, A., and Kleihues, P. Selective induction by A'-nitrosoethylurea of oligodendrogliomas in fetal forebrain transplants. Cancer Res., 48: 2871-2875, 1988. 14. Shibata, D. K., Arnheim, N., and Martin, W. J. Detection of human papilloma virus in paraffin-embedded tissue using the polymerase chain reaction. J. Exp. Med., 167: 225-230, 1988. 15. Orila, M., Suzuki, Y., Sekiya, T., and Hayashi, K. A rapid and sensitive detection of point mutations and genetic polymorphisms using polymerase chain reaction. Genomics, 5: 874-879, 1989. 16. Perantoni, A. O., Rice, J. M., Reed, C. D., Watatani. M., and Wenk, M. L. Activated neu oncogene sequences in primary tumors of the peripheral nervous system induced in rats by transplacental exposure to ethylnitrosourea. Proc. Nati. Acad. Sci. USA, 84: 6317-6321, 1987. TUMORS 17. Ohgaki, H., Kleihues, P., and Hard, G. C. K.-ras mutations in spontaneous and chemically induced renal tumors of the ral. Mol. Carcinog., 14: 455459, 1991. 18. Wang, Y., You, M., Reynolds, S. H., Stoner, G. D., and Anderson, M. W. Mutational activation of the cellular Harvey ras oncogene in rat esophageal papillomas induced by methylbenzylnitrosamine. Cancer Res., 50: 15911595, 1990. 19. Weinberg, R. A. Oncogenes, antioncogenes, and the molecular bases of multistep carcinogenesis. Cancer Res., 49: 3713-3721, 1989. 20. Fearon, E. R., and Vogelstein, B. A genetic model for coloren,il tumorigenesis. Cell, 61: 759-767, 1990. 21. Shaw, P., Tardy, S., Benito, E., Obrador, A., and Costa, J. Occurrence of Kiras and pS3 mutations in primary colorectal tumors. Oncogene, 6: 21212128, 1991. 22. Hollstein, M. C., Peri, L., Mandard, A. M., Welsh, J. A., Montesano, R., Metcalf, R. A., Bak, M., and Harris, C. C. Genetic analysis of human esophageal tumors from two high incidence geographic areas: frequent p53 base substitutions and absence of ros mutations. Cancer Res., 51:4102-4106, 1991. 23. Levine, A. J., Momand, J., and Finlay, C. A. The p53 tumor suppressor gene. Nature (Lond.), 351: 453-456, 1991. 24. Frankel, R. H., Bayona, W., Koslow, M., and Newcomb, E. W.p53 mutations in human malignant gliomas: comparison of loss of heterozygosity with mutation frequency. Cancer Res., 52: 1427-1433, 1992. 25. Serra, A., Gaidano, G. L., Revello, D., Guerrasio, A., Ballerini, P., DallaFavera, R., and Saglioi, G. A new Taq I polymorphism in p53 gene. Nucleic Acids Res., 20: 928, 1992. 26. Gaidano, G., Ballerini, P., Gong, J. Z., Inghirami, G., Neri, A., Newcomb, E. W., Magrath, I. T., Knowles, D. M., and Dalia-Pavera, R. p53 mutations in human lymphoid malignancies: association with Burkitt's lymphoma and chronic lymphocytic leukemia. Proc. Nati. Acad. Sci. USA, 88: 5413-5417, 1991. 27. Osborne, R. J., Merlo, G. R., Mitsudomi, T., Venesio, T., Liscia, D. S., Cappa, A. P. M., Chiba, I., Takahashi, T., Nau, M. M., Callahan, R., and Minna, J. D. Mutations in thé p53 gene in primary human breast cancers. Cancer Res., 51: 6194-6198, 1991. 28. Pegg, A. E. Mammalian O '-alkylguanine-DNA alkyltransferase: régulation and importance in response to alkylating carcinogenic and therapeutic agents. Cancer Res., 50: 6119-6129, 1990. 29. Puisieux, A., Lim, S., Groopman, J., and Ozturk, M. Selective targeting of p53 gene mutational hotspots in human cancers by etiologically defined carcinogens. Cancer Res., 51: 6185-6189, 1991. 30. Sukumar, S. ras oncogenes in chemical carcinogenesis. Curr. Top. Microbiol. Immunol., 148: 93-114, 1989. 31. Jones, P. A., Buckley, J. D., Henderson, B. E., Ross, R. K., and Pike, M. C. From gene to carcinogen: a rapidly evolving field in molecular epidemiology. Cancer Res., 51: 3617-3620, 1991. 32. Carter, G., Hughes, D. C., Clark, R. E., McCormick, F., Jacobs, J., Whittaker, J. A., and Padua. R. A. Ras mutations in patients following cytotoxic therapy for lymphoma. Oncogene, 5:411-416, 1990. 33. Malkin, D., Li, F. P., Strong, L. C, Fraumeni, J. F., Nelson, C., Kim, D. H., Kassel, J., Gryka, M. A., Bishoff, F. Z., Tainsky, M. A., and Friend, S. H. Germ line p53 mutations in a familial syndrome of breast cancer, sarco mas, and other neoplasms. Science (Washington DC), 250:1222-1238,1990. 34. Srivastava, S., Zou, Z., Pirollo, K., Blattner, W., and Chang, E. H. Germ line transmission of a mutated p53 gene in a cancerprone family with LiFraumeni syndrome. Nature (Lond.), 348: 747-749, 1990. 35. Milner, J., and Medcalf, E. A. Cotranslation of activated mutant p53 with wild type drives the wild-type p53 protein into the mutant conformation. Cell, 65:765-774, 1991. 2998 Downloaded from cancerres.aacrjournals.org on June 18, 2017. © 1992 American Association for Cancer Research. Selective Mutation of Codons 204 and 213 of the p53 Gene in Rat Tumors Induced by Alkylating N-Nitroso Compounds Hiroko Ohgaki, Gordon C. Hard, Norio Hirota, et al. Cancer Res 1992;52:2995-2998. Updated version E-mail alerts Reprints and Subscriptions Permissions Access the most recent version of this article at: http://cancerres.aacrjournals.org/content/52/10/2995 Sign up to receive free email-alerts related to this article or journal. To order reprints of this article or to subscribe to the journal, contact the AACR Publications Department at [email protected]. To request permission to re-use all or part of this article, contact the AACR Publications Department at [email protected]. Downloaded from cancerres.aacrjournals.org on June 18, 2017. © 1992 American Association for Cancer Research.