Biomedical subjects

Xiaowei Yang

Publications and source records attributed to Xiaowei Yang.

21 records · Page 2Linked to original sources

PubMed2003

P7 antigen expression in human breast cancer.

PURPOSE: Evaluate p7 expression in human breast cancer and determine whether chemotherapy and radiation therapy effect a change in p7 expression. EXPERIMENTAL DESIGN: Using a p7-specific monoclonal antibody with immunohistochemistry and Western immunoblot analyses to assess p7 expression in archival, frozen breast cancer specimens both before and after therapy. RESULTS: A novel 7 kDa protein (p7), originally identified in multidrug-resistant ovarian and breast cancer cell lines, was found to be expressed in 21 of 64 (32%) primary, unselected human breast cancer specimens by immunohistochemistry with the use of a p7-specific monoclonal antibody, 1D7. P7 was observed in malignant cells but not in other types of cells in the breast tissue. Western blot analysis confirmed the 7 kDa polypeptide in p7-positive breast carcinomas identified by immunohistochemistry. P7 expression was significantly associated with breast cancers having distant metastasis and/or local recurrence (P = 0.027, Fisher's exact test). In addition, p7 expression was significantly increased in post-treatment breast cancer biopsy specimens compared with pretreatment breast cancer biopsy specimens in patients with locally advanced breast cancer after 5-fluorouracil chemotherapy and radiation therapy [2 of 15 (13%) pretreatment breast cancers compared with 8 of 15 (53%) post-treatment breast cancers; P = 0.016, McNemar's test]. CONCLUSIONS: These findings demonstrate that expression of p7 is associated with malignant tumor cells in primary breast cancers, especially those showing recurrent or metastatic disease. Its specific association with the malignant phenotype suggests it may have potential for novel target-based therapies. The markedly increased expression in patients with locally advanced disease after neoadjuvant therapy suggests a role for p7 in treatment outcome.

Antigens, Neoplasm↗

PubMed2002

Smoking cessation in methadone maintenance.

AIMS: To evaluate relapse prevention (relapse prevention) and contingency management (contingency management) for optimizing smoking cessation outcomes using nicotine replacement therapy for methadone-maintained tobacco smokers. DESIGN: Experimental, 2 (relapse prevention)x2 (contingency management) repeated measures design using a platform of nicotine replacement therapy featuring a 2-week baseline period, followed by randomization to 12 weeks of treatment, and 6- and 12-month follow-up visits. SETTING: Three narcotic treatment centers in Los Angeles. PARTICIPANTS: One hundred and seventy-five participants who met all inclusion and no exclusion criteria. INTERVENTION: Participants received 12 weeks of nicotine replacement therapy and assignment to one of four conditions: patch-only, relapse prevention + patch, contingency management + patch and relapse prevention + contingency management + patch. MEASUREMENTS: Thrice weekly samples of breath (analyzed for carbon monoxide) and urine (analyzed for metabolites of opiates and cocaine) and weekly self-reported numbers of cigarettes smoked. FINDINGS: Participants (73.1%) completed 12 weeks of treatment. During treatment, those assigned to receive contingency management showed statistically higher rates of smoking abstinence than those not assigned to receive contingencies (F3,4680=6.3, P=0.0003), with no similar effect observed for relapse prevention. At follow-up evaluations, there were no significant differences between conditions. Participants provided more opiate and cocaine-free urines during weeks when they met criteria for smoking abstinence than during weeks when they did not meet these criteria (F1,2054=14.38, P=0.0002; F1,2419=16.52, P<0.0001). CONCLUSIONS: Contingency management optimized outcomes using nicotine replacement therapy for reducing cigarette smoking during treatment for opiate dependence, although long-term effects are not generally maintained. Findings document strong associations between reductions in cigarette smoking and reductions in illicit substance use during treatment.

Adolescent↗

PubMed2002

Microvessel density, expression of estrogen receptor alpha, MIB-1, p53, and c-erbB-2 in inflammatory breast cancer.

PURPOSE AND EXPERIMENTAL DESIGN: The purpose is to define intratumoral microvessel density (MVD) and potential biological markers that correlate with inflammatory breast cancer (IBC), we examined MVD, estrogen receptor a (ER) status, MIB-1 proliferation index, p53, and c-erbB-2 by immunohistochemistry in archival specimens from 67 women diagnosed with breast cancer with or without the inflammatory phenotype at the Institut Salah Azaiz (Tunis, Tunisia). RESULTS: The moderate (25-50/x400 field) to high microvessel count (>50/x400 field) was observed in 23 (51%) of 45 IBC tumors compared with 3 (14%) of 22 non-IBC tumors (P = 0.0031; chi(2) test). The presence of ER was found in 6 (14%) of 44 cases versus 7 (32%) of 22 cases in IBC and non-IBC, respectively (P = 0.10). In this series of 67 patient tumors, the median MVD count in ER-negative breast tumors was 21, whereas the median count was 4 in ER-positive breast tumors (P = 0.08; Wilcoxon rank-sum test). However, MIB-1, p53, and c-erbB-2 were not significantly different between IBC and non-IBC tumors. The intratumoral MVD between IBC and non-IBC was still statistically significant after adjustment for multiple comparisons (P = 0.02; Bonferroni test). CONCLUSIONS: These data suggest that there is an increased MVD in breast cancer with the inflammatory phenotype as compared with breast cancer without the inflammatory phenotype.

Adenocarcinoma↗