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H W Lau

Publications and source records attributed to H W Lau.

6 recordsLinked to original sources
PubMed2006

Wide local excision and radiotherapy for the treatment of ductal carcinoma in situ of the breast: the Hong Kong experience.

AIMS: Breast conservation treatment for ductal carcinoma in situ (DCIS) was unpopular in the Chinese population and the outcome was seldom reported. We conducted a single-centre retrospective study to examine the clinical outcome of women in Hong Kong. MATERIALS AND METHODS: Seventy-five Chinese women were treated with wide local excision and radiotherapy for DCIS of the breast between 1994 and 2003. Only 26 (34.7%) women had non-palpable DCIS detected by screening mammograms. All women were treated with whole breast irradiation of 50 Gy in 2 Gy daily fractions, with 50 (66.7%) women receiving an additional electron boost of 10-16 Gy. RESULTS: The median follow-up was 5.1 years (range 2.0-10.7). At the last assessment, four women developed local recurrences, but all remained disease-free after salvage mastectomy. The 5-year actuarial local failure-free rate and cause-specific survival rate were 92.9% (95% confidence interval 89.4-96.4) and 100.0%, respectively. Cosmetic results were rated as good to excellent in all women. On univariate analysis of prognostic factors for local failure, only a close (< or = 2 mm) final resection margin approached statistical significance (hazard ratio 9.108; 95% confidence interval 0.946-87.655; P = 0.056). The 5-year actuarial local failure-free rates for women with a close (< or = 2 mm) final resection margin and women with wider margins were 77.0 and 98.2%, respectively. CONCLUSIONS: Despite geographical and demographic differences, the clinical outcome after wide local excision and radiotherapy for DCIS of the breast in Chinese women is comparable with that in Western series. Efforts are needed to achieve cosmetically acceptable tumour-free margins greater than 2 mm.

Adult↗
PubMed2003

Expression pattern of a gonadoblastoma candidate gene suggests a role of the Y chromosome in prostate cancer.

The contribution of specific genes on the Y chromosome in the etiology of prostate cancer has been undefined. Genetic mapping studies have identified a gonadoblastoma locus on the human Y chromosome (GBY) that predisposes the dysgenetic gonads of XY sex-reversed patients to tumorigenesis. Recently a candidate gene, the testis-specific protein Y-encoded (TSPY) that resides on the GBY critical region, has been demonstrated to express preferentially in tumor cells in gonadoblastoma and testicular germ cell tumors. TSPY shares high homology to a family of cyclin B binding proteins and has been considered to possibly play a role in cell cycle regulation or cell division. To address the possible involvement of the TSPY gene in prostate cancer, both in situ mRNA hybridization and immunohistochemistry techniques were used to study the expression of this putative GBY gene in prostate specimens. Our results demonstrated that TSPY was expressed at low levels in normal epithelial cells and benign prostatic hyperplasia (BPH), but at elevated levels in tumor cells of prostate cancers at various degrees of malignancy. Sequence analysis of RT-PCR products obtained from both prostatic and testicular tissues using specific primers flanking the open reading frame of the TSPY mRNA revealed a complex pattern of RNA processing of the TSPY transcripts involving cryptic intron splicing and/or intron skipping. The variant transcripts encode a variety of polymorphic isoforms or shortened versions of the TSPY protein, some of which might possess different biochemical and/or functional properties. The abbreviated transcripts were more abundant in prostatic cancer tissues than the testicular ones. Although the exact nature of such variant TSPY transcripts and proteins is still unclear, their differential expression suggests that the TSPY gene may also be involved in the multi-step prostatic oncogenesis besides its putative role in gonadoblastoma and testicular seminoma.

Alternative Splicing↗
PubMed1988

Liver composition and lipid metabolism in NZB/W F1 female mice fed dehydroisoandrosterone.

The beneficial effects obtained with dehydroisoandrosterone (DHA) feeding in the treatment of murine systemic lupus erythematosus are similar to those obtained with caloric restriction or with dietary manipulation of essential fatty acid availability. In this study, the fatty acid composition of selected tissues was examined in NZB/W F1 mice fed a diet containing 0.4% DHA. The effect of the DHA diet on liver composition and the activity of key hepatic enzymes involved in fatty acid synthesis and glucose metabolism was also investigated. The content of the essential fatty acid, arachidonate, was decreased in plasma cholesteryl esters and liver and kidney phospholipids in mice fed the DHA diet, yet no significant decrease in arachidonate content was observed in plasma phospholipid. The most striking change in both plasma and liver phospholipid was an increase in palmitic acid and a decrease in stearic acid, which could result from a decreased ability for fatty acid elongation. The liver mass was dramatically increased in the mice fed DHA, primarily from parenchymal cell hypertrophy, and contained little lipid. Significant changes in the activities of malic enzyme, glucose-6-phosphate dehydrogenase and pyruvate kinase, similar to those changes which occur with fasting, were observed during the initial adaptation to the DHA diet. The pyruvate kinase activity remained low, suggesting a decrease in liver glycolysis. These results are consistent with the concept that diets containing DHA result in an altered metabolism with a decreased dependence on carbohydrate metabolism and an increased metabolism of lipids.

Animals↗