ß-Lapachone, a plant product, has been shown to be a novel inhibitor of DNA topoisomerase I, with a mode of action different from camptothecin and a chemical structure distinct from those of current anti-cancer drugs. We observed that ß-lapachone, at concentrations of less than 8 UM, induces cell death with characteristics of apoptosis in human prostate cancer cell lines. This effect of ß-la...

A subtractive thyroid cDNA library was constructed from two human thyroid carcinoma cell lines originating from an anaplastic carcinoma and a papillary thyroid carcinoma. The library was used to identify genes correlated with the progression to a highly malignant phenotype. The thymosin ß-10gene was isolated and found to be expressed at much higher levels in the anaplastic cell line than in th...

We isolated a novel gene, !/'(/. that showed significant homology to the adenomatous polyposis coli (APC} tumor suppressor gene. This novel gene, located on chromosome I9pl3.3, encodes a protein of 2303 amino acids that is expressed specifically in the brain. The predicted protein of APCL contains five copies of a 20-amino-acid motif (FXVEXTPXCFSRXSSLSSLS). Like APC, this domain of APCL was abl...

The four receptor tyrosine kinase I receptors, ErbB-1, ErbB-2, ErbB-3, and KrbB-4, which have been implicated in the development of a variety of normal and malignant tissues, are activated through ligand mediated homoand hctcrodimerization. We have previously reported the frequent coexpression, heterodimerzation, and prognostic significance of ErbB-2 and ErbB-4 in childhood medulloblastoma, an ...

Among 222 primary colorectal cancers we examined, 58 showed no detectable APC mutations by the protein truncation test. We screened those 58 tumors for somatic mutations in the ß-catenin gene. Although amino acid substitutions in serine or threonine residues in exon 3 had been reported, we found no such mutations; however, in seven tumors, we detected somatic interstitial deletions of 234-760 ...

The morphology of neoplasms in the nasal olfactory region of the Syrian golden hamster observed after s.c. injections of di-/!-propylnitrosamine, ß-hydroxypropyl-H-propylnitrosamine, ß-oxopropyl-;i-propylnitrosamine, and methyl-/J-propylnitrosamine are described; all four compounds induced tumors. Neoplastia lesions were characterized by the proliferation of three often intermingled cell type...

background: colorectal adenocarcinoma is one of the most prevalent and treatable malignancies of the gastrointestinal tract. recent in vitro studies have demonstrated the anticancer effect of calendula officinalis extract on a tumor cell line derived from colorectal cancers. the inhibitory effect of this extract ranges from 70- 100% and an in vitro study has demonstrated that calendula officina...

Mutation of the adenomatous polyposis coli i t/'< i tumor suppressor gene initiates the majority of coloréela!(CR) cancers. One consequence of this inactivation is constitutive activation of ß-catenin/Tcf-mediated tran scription. To further explore the role of the APC/ß-catenin/Tcf pathway in CR tumorigenesis, we searched for mutations in genes implicated in this pathway in CR tumors lacking...

Type I interferons (IFNa and IFN/3) are presently used in the adjuvant treatment of several human cancers. However, these cytokines have dem onstrated only modest success in breast cancer therapy, and research efforts have focused on improving their efficacy. Recent progress in understanding the molecular mechanisms underlying the antiproliferative effects of IFNs has identified the cytoplasmic...

We recently established transfectants of MCF-7 human breast cancer cells with fibroblast growth factor 4 (Jgf-4) that showed rapid growth and spontaneous metastasis in ovariectomized and tamoxifen-treated nude mice. To establish a spontaneous metastatic model of human breast cancer cells in nude mice with a sensitive marker for detection of micrometastasis, the transfection offgf-4 was combined...