Learn More
Spontaneous errors in DNA replication have been suggested to play a significant role in neoplastic transformation and to explain the chromosomal alterations seen in cancer cells. A defective replication factor could increase the mutation rate in clonal variants arising during tumour progression, but despite intensive efforts, increases in tumour cell(More)
Using in vitro gene amplification by the polymerase chain reaction (PCR) and mutation detection by the RNAase A mismatch cleavage method, we have examined c-K-ras genes in human pancreatic carcinomas. We used frozen tumor specimens and single 5 micron sections from formalin-fixed, paraffin-embedded tumor tissue surgically removed or obtained at autopsy.(More)
  • N Rampino, H Yamamoto, Y Ionov, Y Li, H Sawai, J C Reed +1 other
  • 1997
Cancers of the microsatellite mutator phenotype (MMP) show exaggerated genomic instability at simple repeat sequences. More than 50 percent (21 out of 41) of human MMP+ colon adenocarcinomas examined were found to have frameshift mutations in a tract of eight deoxyguanosines [(G)8] within BAX, a gene that promotes apoptosis. These mutations were absent in(More)
RNAse A mismatch cleavage analysis of 66 primary human colon tumors reveals a high incidence of K-ras genes with mutations at position 12. No apparent correlation was found between the presence of mutant oncogenes and the degree of invasiveness of the tumours but evidence for ras mutational activation in premalignant tissue was obtained.
DNA from T24, a cell line derived from a human bladder carcinoma, can induce the morphological transformation of NIH 3T3 cells. Using techniques of gene rescue to clone the gene responsible for this transformation, we have found that it is human in origin, less than 5 kilobase pairs in size and is homologous to a 1,100-base polyadenylated RNA species found(More)
We have screened different cultured cell lines established from human tumors for the ability of their DNAs to induce transformed foci in NIH/3T3 cells. Based on restriction endonuclease digestions and the presence of human sequences in mouse transformants, we conclude that five of these human tumor cell lines contain a gene or genes capable of transforming(More)
The frequency of point mutations at codons 12 and 13 of the c-K-ras gene has been determined in a panel of more than 400 human tumors. Mutant c-K-ras genes were detected in about 75% of adenocarcinomas of the pancreas (n = 84); 40% of adenomas (n = 72) and carcinomas (n = 244) of the colon end rectum; 30% of carcinomas of the bile duct (n = 19); 25% of(More)
The calcium phosphate precipitation method of Graham and van der Eb (1973) is an efficent means of introducing DNA into culturaed animal cells. Cells which incorporate one selectable marker are also likely to incorporate one selectable marker are also likely to incorporate sequences from the carrier DNA. Both selected and unselected markers are found(More)