The expression level of the androgen receptor (AR) gene in androgen-dependent and -independent prostate cancer was determined by using real-time quantitative reverse transcription-PCR assay. Eight benign prostate hyperplasias, 33 untreated and 13 hormone-refractory locally recurrent carcinomas, as well as 10 prostate cancer xenografts, were analyzed. All hormone-refractory tumors expressed AR a...

The role of oncogene or tumor supressor gene in Epstein-Barr virus (EBV) associated malignant lymphomas (MLs) is poorly understood. We examined 36 MLs (21 EBV positive and 15 EBV negative) and 6 reactive hyperplasias for the presence of myc gene amplification. Polymerase chain reaction (PCR) technology was used to examine the state of amplification of the proto-oncogene c-myc in formalin-fixed ...

BACKGROUND The aim of the study was to test for human papilloma virus (HPV) infection and human telomerase RNA component (hTERC) gene amplification in tissues derived from esophageal cancer, in esophagus displaying atypical hyperplasia and in normal tissue, and to analyze the relationship between them and discuss whether HPV infection and hTERC gene amplification play a role in the duration of ...

Weed populations can have high genetic plasticity and rapid responses to environmental selection pressures. For example, 100-fold amplification of the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene evolved in the weed species Amaranthus palmeri to confer resistance to glyphosate, the world's most important herbicide. However, the gene amplification mechanism is unknown. We sequenced t...

To study the effect of apoptosis on gene amplification, we have constructed HeLa S3 cell lines in which the expression of bcl-2 (BCL2) can be controlled by tetracycline in the growth medium. Induction of Bcl-2 expression caused a temporary delay of apoptosis and resulted in roughly a 3-fold increase in the frequency of resistant colonies when cells were selected with trimetrexate. This resistan...

PRAD-1 is a putative oncogene localized on chromosome 11q13 which encodes cyclin D1, a novel cyclin involved in cell cycle regulation. Amplification of this gene has recently been reported in several human tumors including breast and head and neck carcinomas. In this study we have analyzed the presence of PRAD-1/cyclin D1 gene amplification and mRNA overexpression in a series of 46 matched norm...

MDM4, a homolog of MDM2, is considered a key negative regulator of p53. Gene amplification of MDM4 has been identified in a variety of tumors. MDM2 or MDM4 gene amplification is only associated with the wild-type TP53 gene in retinoblastomas, thus the amplification of the two genes is mutually exclusive. Previously, we demonstrated that MDM2 amplification and TP53 alteration were not mutually e...