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Biomedical subjects

Richard D Williams

Publications and source records attributed to Richard D Williams.

25 records · Page 2Linked to original sources
PubMed2003

WT1 expression does not disrupt myogenic differentiation in C2C12 murine myoblasts or in human rhabdomyosarcoma.

WT1 encodes a tissue-specific transcription factor important in early mesenchymal differentiation. Altered expression or mutation of WT1 occurs in malignancies derived from such tissues. These include Wilms tumour, a paediatric kidney cancer that may show heterologous differentiation into primitive skeletal muscle, especially in tumours with WT1 mutation. A putative role for WT1 in inhibiting myogenesis has been suggested by transient transfection of C(2)C(12) myoblasts. However, using a more robust model of stable transfectants of C(2)C(12) expressing inducible WT1 isoforms, we found no inhibition of myogenic differentiation. We also investigated a possible role for WT1 in the disrupted myogenesis seen in rhabdomyosarcoma, a paediatric cancer resembling foetal skeletal muscle. WT1 expression levels measured by quantitative real-time reverse transcription polymerase chain reaction were low or absent in those tumours with a PAX-FKHR fusion gene characteristic of the alveolar subtype, and were higher in cases lacking these fusion genes. Overall, there was a weak positive correlation between expression of myogenic differentiation marker genes and WT1 levels. We conclude that expression of WT1 in C(2)C(12) cells and in rhabdomyosarcoma does not inhibit myogenic differentiation.

Animals↗
PubMed2003

Infection of human urethral epithelium with Neisseria gonorrhoeae elicits an upregulation of host anti-apoptotic factors and protects cells from staurosporine-induced apoptosis.

In order to better understand the host response to an infection with Neisseria gonorrhoeae, microarray technology was used to analyse the gene expression profile between uninfected and infected human urethral epithelium. The anti-apoptotic genes bfl-1, cox-2 and c-IAP-2 were identified to be upregulated approximately eight-, four- or twofold, respectively, following infection. Subsequent assays including RT-PCR, real time RT-PCR and RNase protection confirmed the increased expression of these apoptotic regulators, and identified that a fourth anti-apoptotic factor, mcl-1, is also upregulated. RT-PCR and RNase protection also showed that key pro-apoptotic factors including bax, bad and bak do not change in expression. Furthermore, our studies demonstrated that infection with the gonococcus partially protects urethral epithelium from apoptosis induced by the protein kinase inhibitor, staurosporine (STS). This work shows that following infection with Neisseria gonorrhoeae, several host anti-apoptotic factors are upregulated. In addition, a gonococcal infection protects host cells from subsequent STS-induced death. The regulation of host cell death by the gonococcus may represent a mechanism employed by this pathogen to survive and proliferate in host epithelium.

Apoptosis↗
PubMed2003

Cancer fear and mood disturbance after radical prostatectomy: consequences of biochemical evidence of recurrence.

PURPOSE: Biochemical recurrence of prostate cancer often precedes any clinical sign or symptom of disease recurrence by several years. Thus, patients may have laboratory evidence of recurrence and do not know what it portends in terms of the future disease course. Little is known about the emotional consequences of biochemical recurrence. We compared cancer fear and mood disturbance in men with biochemical recurrence of prostate cancer versus those without recurrence. In addition, associations among urinary symptoms, cancer fear and mood disturbance were examined. MATERIALS AND METHODS: A survey including the American Urological Association symptom index, a cancer fear measure and the Profile of Mood States was mailed to patients at a urology clinic at a tertiary care hospital in 1999. Of the sample of 270 patients with prostate cancer who underwent radical prostatectomy 126 (47%) responded to the mailed survey. A total of 45 men with biochemical prostate cancer recurrence were compared to 81 patients without recurrence. RESULTS: Higher urinary tract symptoms were associated with increased cancer fear and mood disturbance (each p <0.05). Biochemical cancer recurrence was not independently associated with increased cancer fear and mood disturbance. However, men with biochemical recurrence and more severe urinary tract symptoms reported the highest levels of cancer fear and mood disturbance (each p <0.01). CONCLUSIONS: Psychological distress was highest in men with biochemical recurrence and elevated clinical symptoms. Urinary symptoms may be an important contributor to psychological distress in patients with prostate cancer who have biochemical recurrence.

Aged↗
PubMed2002

Induction and regulation of tumor necrosis factor-related apoptosis-inducing ligand/Apo-2 ligand-mediated apoptosis in renal cell carcinoma.

The lack of effective therapy for disseminated renal cell carcinoma (RCC) has stimulated the search for novel treatments including immunotherapeutic strategies. However, poor therapeutic responses and marked toxicity associated with immunological agents has limited their use. The tumor necrosis factor family member tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)/Apo-2 ligand induces apoptosis in a variety of tumor cell types, while having little cytotoxic activity against normal cells. In this study the activation and regulation of TRAIL-induced apoptosis and TRAIL receptor expression in human RCC cell lines and pathologic specimens was examined. TRAIL induced caspase-mediated apoptotic death of RCC cells with variable sensitivities among the cell lines tested. Compared with TRAIL-sensitive RCC cell lines (A-498, ACHN, and 769-P), the TRAIL-resistant RCC cell line (786-O) expressed lesser amounts of the death-inducing TRAIL receptors, and greater amounts of survivin, an inhibitor of apoptosis. Incubation of 786-O with actinomycin D increased the expression of the death-inducing TRAIL receptors and, concomitantly, decreased the intracellular levels of survivin, resulting in TRAIL-induced apoptotic death. The link between survivin and TRAIL regulation was confirmed when an increase in TRAIL resistance was observed after overexpression of survivin in the TRAIL-sensitive, survivin-negative RCC line A-498. These findings, along with our observation that TRAIL receptors are expressed in RCC tumor tissue, suggest that TRAIL may be useful as a therapeutic agent for RCC and that survivin may partially regulate TRAIL-induced cell death.

Adult↗
PubMed2002

Testosterone therapy in late-life major depression in males.

BACKGROUND: Major depression associated with aging in males may improve with anabolic/androgenic steroid therapy. The efficacy and safety of testosterone therapy in the treatment of depression in elderly hypogonadal males is inconclusive. The following study identifies a subgroup of elderly depressed males who may benefit from testosterone therapy. METHOD: Participants included 16 elderly eugonadal males with major depressive disorder (DSM-IV criteria) and a Hamilton Rating Scale for Depression (HAM-D) score > 18. Following a single-blind 2-week placebo lead-in, patients were randomly assigned to treatment with either a physiologic dose of testosterone cypionate (TC), 100 mg/week, or supraphysiologic dose of 200 mg/week IM for 6 weeks. Psychometric testing was carried out at entry into the study, at the TC injection baseline, and every 2 weeks thereafter. Tests included an objective measurement, the HAM-D, and the Buss-Durkee Hostility Inventory. RESULTS: One patient meeting inclusion criteria responded during the placebo lead-in; thus, 15 patients were randomly assigned to treatment (100 mg/week, N = 8; 200 mg/week, N = 7). There was a 42% decrease in the mean HAM-D scores from 20.1 to 11.9 (p <.0001). However, the majority of the change was due to improvement in the 10 late-onset (< or = 45 years old) depression patients, whose mean HAM-D score decreased from 19.8 to 9.3 (53%), versus the 5 early-onset depression patients, whose mean HAM-D score decreased from 20.8 to 17.0 (18%) (p =.0110). The TC dose did not affect the response. Similar HAM-D decreases of 43% and 41% occurred for the respective 100- and 200-mg/week doses. The HAM-D responder analysis found that none of 5 early-onset patients had HAM-D response, whereas 6 (60%) of 10 late-onset patients responded (p =.025). Similarly, none of the early-onset patients experienced a remission whereas 5 (50%) of the late-onset patients were categorized as remitters (p =.053). Correlations between the peak and mean total testosterone concentrations and HAM-D change scores suggested that only minimal TC doses were required to produce an antidepressant effect. CONCLUSION: These data suggest that testosterone therapy would best be limited to men with late-onset depression. The findings suggest that short-term therapy with TC is safe. Long-term treatment safety is unknown. Psychiatrists using testosterone therapy should ascertain that patients have been recently valuated for prostate cancer. If testosterone therapy is initiated, serial serum prostate-specific antigen sampling should be used for monitoring patients' prostate status.

Anabolic Agents↗
PubMedDate not supplied

Meta-analysis and pooled re-analysis of copy number changes in colorectal cancer detected by comparative genomic hybridization.

BACKGROUND: Comparative genomic hybridization (CGH) provides an insight into chromosomal changes associated with colorectal cancer (CRC) development. However, a problem with many studies is the limited cohort size, making the significance of some findings unclear. MATERIALS AND METHODS: To derive a better insight into the chromosomal changes associated with CRC, we performed a meta-analysis and pooled re-analysis of published metaphase CGH data. RESULTS: In addition to recurrent alterations, gains of 20 13q, 8q and 7p and loss of 18, 17p, 8p and 4p, pooling identified less frequent, but significant changes, including gain of 1q and 3, and losses from 6q, 9p and 21q. CONCLUSION: These additional alterations may be characteristic of some tumors and thus have relevance to CRC biology. Meta-analysis not only has the potential to detect novel changes, present at low frequency in several independent studies, but can provide greater reliability for their detection than single studies alone.

Adenoma↗