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Jan C Liang

Publications and source records attributed to Jan C Liang.

2 recordsLinked to original sources

Genetic markers useful for distinguishing between organ-confined and locally advanced prostate cancer.

Prostate cancer is one of the most commonly diagnosed cancers and the second leading cause of cancer deaths among men in the United States. In this study, we performed comparative genomic hybridization (CGH) on 45 primary prostate adenocarcinomas to determine genetic markers that could be useful for distinguishing between organ-confined and locally advanced prostate cancer. Of these tumors, 24 were pT2 stage, 21 were pT3b; 20 had low Gleason scores (GS), 25 had high GS. The most common chromosomal alterations in all 45 tumors included losses on 8p (57.8%), 10q21-->qter (40.0%), 16q (35.6%), 11q21-->qter (28.9%), 16p (22.2%), 6q22-->24 (22.2%), 10p (20.0%), 5q31-->qter (17.8%), 6p (17.8%), 15q22-->qter (15.6%), and 17p (15.6%) as well as gains on 7cen-->p14 (20.0%), 7cen-->q22 (20.0%), and Xcen-->q21 (17.8%). Contingency table analysis showed that losses of 8p, 10q25-->qter, 6p21, 6q24-->qter, and 15q22-->qter were significantly increased in frequency (P < 0.05) with increasing stage and/or GS. A model was created following multivariate logistic regression analysis that was predictive of tumor stage in approximately 90% of the tumors studied. This model suggests that loss of 8p is the most valuable predictor of stage. These findings suggest that chromosomal regions identified in this study may be useful for distinguishing between organ-confined and locally advanced prostate tumors.

Adenocarcinoma↗

A novel, evolutionarily conserved gene family with putative sequence-specific single-stranded DNA-binding activity.

Complete and partial deletions of chromosome 5q are recurrent cytogenetic anomalies associated with aggressive myeloid malignancies. Earlier, we identified an approximately 1.5-Mb region of loss at 5q13.3 between the loci D5S672 and D5S620 in primary leukemic blasts. A leukemic cell line, ML3, is diploid for all of chromosome 5, except for an inversion-coupled translocation within the D5S672-D5S620 interval. Here, we report the development of a bacterial artificial chromosome (BAC) contig to define the breakpoint and the identification of a novel gene SSBP2, the target of disruption in ML3 cells. A preliminary evaluation of SSBP2 as a tumor suppressor gene in primary leukemic blasts and cell lines suggests that the remaining allele does not undergo intragenic mutations. SSBP2 is one of three members of a closely related, evolutionarily conserved, and ubiquitously expressed gene family. SSBP3 is the human ortholog of a chicken gene, CSDP, that encodes a sequence-specific single-stranded DNA-binding protein. SSBP3 localizes to chromosome 1p31.3, and the third member, SSBP4, maps to chromosome 19p13.1. Chromosomal localization and the putative single-stranded DNA-binding activity suggest that all three members of this family are capable of potential tumor suppressor activity by gene dosage or other epigenetic mechanisms.

Amino Acid Sequence↗