Joanna Groden

Learn More
The Bloom's syndrome (BS) gene, BLM, plays an important role in the maintenance of genomic stability in somatic cells. A candidate for BLM was identified by direct selection of a cDNA derived from a 250 kb segment of the genome to which BLM had been assigned by somatic crossover point mapping. In this novel mapping method, cells were used from persons with(More)
The expression of carcino-embryonic antigen by colorectal cancer is an example of oncogenic activation of embryonic gene expression. Hypothesizing that oncogenesis-recapitulating-ontogenesis may represent a broad programmatic commitment, we compared gene expression patterns of human colorectal cancers (CRCs) and mouse colon tumor models to those of mouse(More)
D1Z2 is a highly polymorphic DNA locus composed of a tandem of repetitive units. Its molecular constitution has been examined in 61 clonal cell lines selected at random from two lymphoblastoid cell lines (LCLs), each of which had been proliferating in vitro for several hundred days. Thirty-three of the cells were selected from an LCL derived from the blood(More)
Persons with the autosomal recessive disorder Bloom syndrome are predisposed to cancers of many types due to loss-of-function mutations in the BLM gene, which encodes a recQ-like helicase. Here we show that mice heterozygous for a targeted null mutation of Blm, the murine homolog of BLM, develop lymphoma earlier than wild-type littermates in response to(More)
MicroRNA deregulation is frequent in human colorectal cancers (CRCs), but little is known as to whether it represents a bystander event or actually drives tumor progression in vivo. We show that miR-135b overexpression is triggered in mice and humans by APC loss, PTEN/PI3K pathway deregulation, and SRC overexpression and promotes tumor transformation and(More)
Inherited mutations of the APC gene predispose carriers to multiple adenomatous polyps of the colon and rectum and to colorectal cancer. Mutations located at the extreme 5' end of the APC gene, however, are associated with a less severe disease known as attenuated adenomatous polyposis coli (AAPC). Many individuals with AAPC develop relatively few(More)
RecQ helicases are critical for maintaining genomic integrity. In this study, we show that three RecQ members (WRN, deficient in the Werner syndrome; BLM, deficient in the Bloom syndrome; and Drosophila melanogaster RecQ5b (dmRecQ5b)) possess a novel strand pairing activity. Furthermore, each of these enzymes combines this strand pairing activity with its(More)
Gastrointestinal cancer affects 250,000 Americans a year with nearly half of those cases being colorectal cancer. The Wnt pathway is activated in most spontaneous and familial colorectal cancers and has been implicated in tumor formation at other sites in the gastrointestinal tract. In human tumors, the Wnt pathway is most often altered by mutations(More)
Studies of Wnt activation in gastric cancer have yielded conflicting results. The goals of this study were to determine the frequency of Wnt pathway activation and beta-catenin mutation in these tumors. Three hundred eleven gastric cancers were examined for beta-catenin expression by immunostaining and dissected using laser capture microscopy to obtain DNA(More)