Wei-Hwa Lee

Down regulation of bcl‐2 by p53 in nasopharyngeal carcinoma and lack of detection of its specific t(14;18) chromosomal translocation in fixed tissues

High levels of bcl‐2 protein have been found in a wide variety of human cancers. Since p53 gene inactivation occurs in over half of human cancers, it is possible that loss of p53‐mediated repression of bcl‐2 gene expression accounts, at least in part, for the frequent abnormalities in bcl‐2 protein production seen in tumours. By using immunohistochemical methods, we have analysed thirty‐three nasopharyngeal carcinomas for p53 and bcl‐2 expression. We found an inverse correlation between the expression of these two proteins (P < 0.001). Moreover, we utilized universal oligonucelotide primers of a region 5′ to the bcl‐2 MBR and at the 3′ end of JH segments to initiate a DNA polymerase chain reaction that amplified these bcl‐2‐JH junctures. Of the twelve nasopharyngeal carcinomas expressing bcl‐2, none showed a t(14;18) chromosome translocation. These findings may indicate potential mechanisms by which bcl‐2 regulates apoptosis.

Differential expression of the human metastasis adhesion molecule CD44V in normal and carcinomatous stomach mucosa of chinese subjects

Background. CD44 is a cell surface adhesion molecule involved in cell‐cell and cell‐matrix interactions. Tumor cells transfected to overexpress the isoform CD44V readily gain access to lymph nodes and form distant metastases.

Apoptosis occurs more frequently in intraductal carcinoma than in infiltrating duct carcinoma of human breast cancer and correlates with altered p53 expression: Detected by terminal-deoxynucleotidyl-transferase- mediated dUTP-FITC nick end labelling (TUNEL)

We examined the relationship between apoptosis and three different major stages of human breast carcinoma: intraductal carcinoma (DCIS), infiltrating duct carcinoma (IDC) and metastatic carcinoma in lymph nodes. We also determined the correlation between apoptosis and oestrogen receptor (ER), progesterone receptor (PR) and p53.

The extent of proliferative and apoptotic activity in intraductal and invasive ductal breast carcinomas detected by ki-67 labeling and terminal deoxynucleotidyl transferase-mediated digoxigenin-11-dUTP nick end labeling

The balance among cell proliferation, cell differentiation, and cell death determines the cell number in a population as well as the size or even the stage of a tumor. Thus, to improve our understanding of the pathogenesis of neoplasms, it is important to investigate the regulation of both cell proliferation and cell death.

Transitional Cell Carcinoma of the Labia Minor: Evidence of Contact Implantation of Bladder Cancer

A 63-year-old woman underwent transurethral resection of bladder tumors in 1989 and 1991 due to grade 1 to 2, stage pT1 transitional cell carcinoma. Followup outpatient cystourethroscopy and urine cytology every 3 months revealed no disease. In 1993 the patient underwent resection of an anterior urethral tumor on the posterior lip due to mild urethral obstruction and easy contact bleeding. Histology confirmed grade 1 to 2, stage pTa transitional cell carcinoma. Subsequently the patient was closely followed for possible recurrence. In April 1995 during routine cystoscopy 2 tiny nodular lesions on each labia minor were noted in contact with the urethral meatus (fig. 1). Wide excision of the tumors was performed and patholoecal evaluation revealed grade 1, stage pTa transitional cell carcinoma (fig. 2). Convalescence was uneventful and the patient remains disease-free.