Establishing a complementary diagnostic for anti-PD-1 immune checkpoint inhibitor therapy

The role of tumor PD-L1 expression was investigated across the nivolumab clinical development program. Phase III nivolumab trials have shown that patients with tumors not expressing PD-L1 may benefit; therefore, testing is not required to select patients for therapy. The Dako PD-L1 IHC 28-8 pharmDx assay may be used to determine tumor PD-L1 expression as a complementary and informative test.

Prevalence of restless legs syndrome and sleep quality in carriers of the fragile X premutation

This study examined the relationship between the fragile X premutation and restless legs syndrome (RLS). Demographic, medical history and survey responses related to sleep were collected from 213 participants (127 carriers and 86 age matched controls). Subjects were asked about the presence of the four formal diagnostic criteria for RLS. Individuals with the premutation were 1.9 times as likely to meet criteria for RLS (95% CI 1.1–3.2, p=0.025) as controls. Premutation carriers with RLS also experienced significantly worse symptoms than matched controls with adjusted mean scores of 15.1±8.8 vs 7.9±4.4, respectively on the International Restless Legs Scale (IRLS). As markers for domains of sleep disturbance, all subjects completed the Epworth Sleepiness Scale (ESS), the Insomnia Severity Index (ISA) and the Pittsburgh Sleep Quality Index (PSQI). Premutation carriers demonstrated significantly more pathology on these tests except for the ESS where there was a trend towards increased daytime sleepiness in carriers. RLS joins a host of other conditions that should be carefully screened for in those carrying the fragile X premutation and sleep should be a focus for clinicians providing care to them.

Memantine for fragile X-associated tremor/ataxia syndrome: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

Memantine, an uncompetitive N-methyl-d-aspartate receptor antagonist, is currently approved by the US Food and Drug Administration for the treatment of moderate to severe Alzheimer's disease. Anecdotal reports have suggested that memantine may improve neurologic and cognitive symptoms of individuals with the neurodegenerative disease fragile X-associated tremor/ataxia syndrome (FXTAS); however, its efficacy and safety in this population have not been assessed in a controlled trial.

METHOD

Individuals with FXTAS aged 34-80 years were enrolled in a randomized, double-blind, placebo-controlled, 1-year trial between September 2007 and August 2012. Inclusion required definite, probable, or possible FXTAS in clinical stages 1-5 according to previously published criteria. Primary outcome measures were the Behavioral Dyscontrol Scale (BDS) score and CATSYS intention tremor severity.

RESULTS

Ninety-four participants were randomized from 205 screened; of those, 43 and 45 started treatment with memantine (titrated to 10 mg twice daily) and placebo, respectively. Thirty-four participants receiving memantine and 36 receiving placebo completed the 1-year endpoint assessment (n = 70). Intention-to-treat analysis showed no improvement with respect to intention tremor severity (mean [SD] values with memantine vs placebo: 1.05 [0.73] vs 1.89 [2.19], P = .047) or BDS score (16.12 [5.43] vs 15.72 [3.93], P = .727) at follow-up. Post hoc analyses of participants with early FXTAS (stage ≤ 3), those with late FXTAS (stage > 3), and those in different age groups (≤ 65 years and > 65 years) also indicated no significant improvement. More frequent mild adverse events were observed in the placebo group, while more frequent moderate adverse events occurred in the memantine group (P = .007).

CONCLUSION

This randomized, double-blind, placebo-controlled trial of memantine for individuals with FXTAS showed no benefit compared to placebo with respect to the selected outcome measures.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00584948.

COGNITIVE DYSFUNCTION IN FMR1 PREMUTATION CARRIERS

Premutation carriers of the fragile X mental retardation gene (especially men) older than 50 may develop a neurodegenerative disease, the fragile X-associated tremor/ataxia syndrome (FXTAS). Carriers may present with varied cognitive impairments. Attention, working memory, declarative and procedural learning, information processing speed, and recall are among the cognitive domains affected. Executive dysfunction is a prominent deficit, which has been demonstrated mostly in men with FXTAS. In more advanced stages of FXTAS, both men and women may develop a mixed cortical-subcortical dementia, manifested by psychomotor slowing and deficits in attention, retrieval, recall, visuospatial skills, occasional apraxia, as well as overt personality changes. Studies have shown dementia rates as high as 37-42% in older men with FXTAS, although more research is needed to understand the prevalence and risk factors of dementia in women with FXTAS. Neuropsychiatric symptoms are common and reflect the dysfunction of underlying frontal-subcortical neural circuits, along with components of the cerebellar cognitive affective syndrome. These include labile or depressed mood, anxiety, disinhibition, impulsivity, and (rarely) psychotic symptoms. In this paper we review the information available to date regarding the prevalence and clinical picture of FXTAS dementia. Differential diagnosis may be difficult, given overlapping motor and non-motor signs with several other neurodegenerative diseases. Anecdotal response to cholinesterase inhibitors and memantine has been reported, while symptomatic treatments can address the neuropsychiatric manifestations of FXTAS dementia.

Prediction of survival by immunohistochemical stains (IHC) in stage D2 prostate cancer patients (pts): The importance of pTEN overexpression

e16019

Background: Several signal transduction pathways,important for apoptosis and angiogenesis were idendified and their expression and correlation with survival was studied by IHC in archival prostate cancer biopsies. All pts has androgen deprivation for stage D2 disease and were followed at 3 month intervals. Methods: In an IRB approved study,42 pts had adequate tissue preserved between 1992 and 2006 and their charts were reviewed retrospectively.IHC stains to detect tumor expression of S6(ribosomal),p70s6,pTEN,AKT-1,BCL-1(Cyclin D1),VEGF,c-KIT,PDGFR-alpha and PDGFR-beta were performed by US Labs(Irvine,CA).All results were independently evaluated by two pathologists.Immunoreactivity was scored using a semiquantitative system combining intensity of staining(0–3+) and percentage of cells staining positive(0–3+).The total score was obtained by adding the scores for indensity and the percentage of positive cells,then averaging the resuts obtained by each reader.For the purpose of this study, stain intensity of 0–1+ was considered negative and the intensity of 2–3+ was considered positive.A Cox regression survival model for each stain was developed with variables known to predict survival :Gleason score,Hemoglobin(Hgb),Alkaline Phosphatase(Alk Phos),Prostate Specific Antigen(PSA),Lactate Dehydrogenase(LDH) levels. Results: The median values were: age 70yrs(56–92),Gleason score 8(6–10), LDH 171 IU/L(97–350),Hgb 12.9gm/dl (6.8–16.3), PSA 188ng/ml(2–5677),Alk Phos 139U/L(60–1756),survival 851 days(163- 6102).In univariate analysis,VEGF staining was predictive of survival (p<0.037) but not in multivariate analysis.The pTEN staining correlated with survival (p<0.0367) and a hazard ratio of 0.040 in multivariate analysis. Conclusions: In this small sample of pts, overexpression of S6,p70s6,AKT-1,BCL-1,VEGF,c-KIT,PDGFR-alpha and PDGFR-beta by IHC staining did not predict survival independently.The pTEN staining,however was strong predictor of survival in the multivariate analysis.

No significant financial relationships to disclose.

Comorbidity and survival in advanced non-small cell lung cancer (NSCLC) veteran patients

e20675

Background: Prognostic value of comorbidity at diagnosis has received increasing attention. We studied whether the Charlson Comorbidity Index (CMI), Cumulative Illness Rating Scale (CIRS), Kaplan Feinstein Index (KFI), and/or VA Comorbidity Scale (VA) independently predicted survival for NSCLC patients Methods: In an IRB approved protocol, the charts of 101 patients with Stage IIIA, IIIB or IV Non small cell lung cancer seen from 2004 through 2006 at a VA medical center were reviewed of whom 94 have already died. Comorbidity scores ECOG performance status (PS), stage, number of treatments, serum LDH, and albumin levels were obtained or coded from medical records. Survival analyses were performed using proportional hazards models. Results: Median (M) patient age was 69 years (range 51–88), the M ECOG PS was 1 (range 0–4); 13 (13%) had stage IIIA, 27 (26%) IIB and 62 (61%) IV. The M number of treatments was 1 (range 0–6). Histologies were adenocarcinoma in 48 (48%) pts, squamous cell in 37 (37%) pts, and other 17 (15%) pts. The M survival was 207 days (range 4–1785 days). The Median (and ranges) were: 4.2 (1.2–12.8) for CMI, 3 (0–6) for CIRS15, 5(0–11) for CIRS16, 1.8 (0–4) for CIRS17, 0(0–1) for CIRS18, 2 (0–3) for KFI, and 4 (0–8) for VA. The M albumin was 3.7 (range 1.9–5.3) and LDH 201 (range 104–1036). In univariate survival analyses, the stage (p<0.001), ECOG PS (p<0.001), albumin (p<0.003), and the CIRS 17 (p <0.052) were predictive of survival; when, however, bisected by median values, the VA scale (p<0.027), ECOG PS (p<0.052) and albumin (p<.0017) were significantly related to survival but age, LDH, CMI, KFI and subscales of the CIRS (CIRS 16, CIRS 17, CIRS18) were not related to survival. In multivariate proportional hazards analyses that included stage and a comorbidity index, the CIRS16 (p<.032) was an independent predictor of survival; the combinations of stage (p<0.008), ECOG PS (p<.004), stage (p<.006) and albumin (p<.002) were independent predictors of survival. Conclusions: In this small sample, current comorbidity indices did not add to determinations of survival of veterans with advanced NSCLC. Further research is needed in a larger sample. Supported in part by the New Jersey Commission for Cancer Research 09–1133-CCR-EO and VA HSRD IIR 02–103.

No significant financial relationships to disclose.

FMR1 CGG repeat length predicts motor dysfunction in premutation carriers

BACKGROUND

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a recently described, underrecognized neurodegenerative disorder of aging fragile X mental retardation 1 (FMR1) premutation carriers, particularly men. Core motor features are action tremor, gait ataxia, and parkinsonism. Carriers have expanded CGG repeats (55 to 200); larger expansions cause fragile X syndrome, the most common heritable cause of mental retardation and autism. This study determines whether CGG repeat length correlates with severity and type of motor dysfunction in premutation carriers.

METHODS

Persons aged >or=50 years with a family history of fragile X syndrome underwent structured videotaping. Movement disorder neurologists, blinded to carrier status, scored the tapes using modified standardized rating scales. CGG repeat length analyses for women incorporated the activation ratio, which measures the percentage of normal active chromosome X alleles.

RESULTS

Male carriers (n = 54) had significantly worse total motor scores, especially in tremor and ataxia, than age-matched male noncarriers (n = 51). There was a trend toward a difference between women carriers (n = 82) and noncarriers (n = 39). In men, increasing CGG repeat correlated with greater impairment in all motor signs. In women, when activation ratio was considered, increasing CGG correlated with greater ataxia.

CONCLUSIONS

CGG repeat size is significantly associated with overall motor impairment in premutation carriers. Whereas this association is most pronounced for men and covers overall motor impairment-tremor, ataxia, and parkinsonism-the association exists for ataxia among women carriers. This is the first report of a significant correlation between the premutation status and a motor feature of fragile X-associated tremor/ataxia syndrome in women.

VEGF, PDGF alpha, PDGF beta, and C-Kit expression are not independent survival predictors in stage D2 prostate cancer (PC)

15623

Background: In PC, overexpression of VEGF, PDGF alpha, PDGF beta, and C-Kit has been reported in over 50% of biopsy samples and may be important predictors of survival. Methods: In an ongoing project, we reviewed the records of 26 patients (pts) with stage D2 PC and stained their archival tissue specimens for VEGF, PDGF alpha, PDGF beta, and C-Kit expression. Immunohistochemistry was performed at US LABS (Irvine CA). All immunostains were evaluated by two pathologists. Immunoreactivity was scored using a semiquantitative system for intensity of staining (0–3+) and % of tumor cells (0–3+). The total score was obtained by averaging the scores between the two readers. All pts had androgen deprivation and were followed at 3 months intervals with physical examination, CBC, chemistry profile and PSA levels. A stepwise Cox model was used with variables: Gleason score, Hemoglobin (Hgb), Alkaline Phosphatase (Alk Phos), PSA, LDH levels, and C-Kit positive or negative staining. Results: Median values were as follows: age 69 years (56–91), Alk Phos 139 U/L(60–1298), PSA 178 ng/ml (1.8–5677), LDH 169 IU/L (100–350), Hgb 12.8 gm/dl (6.8–16.3), Gleason score 8 (5–10), Survival 26 mos (8.3–144.1). The median value for C-Kit staining was 3 on a scale of 0–6. 18 pts were grouped into low staining group (0–4) and 8 pts in a high staining group (4.5–5). The Kappa Coefficient for C-Kit was 0.83, and ranged from 0.78–0.91 for the other 3 stains. In univariate survival analyses, C-Kit staining was a predictor for survival (p=0.037) but not PDGF alfa, PDGF beta, or VEGF. In the stepwise Cox model, independent survival predictors in order of significance were the Gleason score, Hgb, and PSA levels. Conclusions: In this sample, VEGF, PDGF alpha, PDGF beta, and C-Kit overexpression by immunohistochemistry in archival tissue are not independent predictors of survival. The C-Kit, however, has a small association with survival but may have collinearity with known predictors of survival.

No significant financial relationships to disclose.

Neuropathic features in fragile X premutation carriers

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a progressive neurological condition occurring in fragile X premutation carriers, predominantly males, and resulting in CNS dysfunction including tremor, ataxia, Parkinsonism, and cognitive decline. Neuropathic signs have also been described. The objective of this study was to compare neuropathic signs in fragile X premutation carriers versus controls and determine the relationship of these signs to CGG repeat length and tremor/ataxia. A neuropathy scale was utilized to compare distal tendon reflexes and vibration sense in subjects from a large cohort of carriers and controls undergoing neurological exam and structured videotaping sessions for movement disorder rating. The male carrier group displayed more impairment on total neuropathy, vibration and reflex scores than the corresponding control group, while female carriers were not significantly different from controls. In males, after correction for age effects, there was a correlation between CGG repeat length and both total neuropathy and reflex impairments. Age-adjusted partial correlation analyses showed an association between neuropathy scores and severity of ataxia but not tremor in carrier males and females. These data suggest that neuropathic signs are associated with the fragile X premutation, presumably occurring through the same mechanism proposed for CNS disease, namely, toxicity from expanded-CGG-repeat FMR1 mRNA.

Progression of tremor and ataxia in male carriers of the FMR1 premutation

Premutation alleles of the fragile X mental retardation 1 (FMR1) gene give rise to a late-onset movement disorder, fragile X-associated tremor/ataxia syndrome (FXTAS), characterized by progressive intention tremor and gait ataxia, with associated dementia and global brain atrophy. The natural history of FXTAS is largely unknown. To address this issue, a family-based, retrospective, longitudinal study was conducted with a cohort of 55 male premutation carriers. Analysis of the progression of the major motor signs of FXTAS, tremor and ataxia, shows that tremor usually occurs first, with median onset at approximately 60 years of age. From the onset of the initial motor sign, median delay of onset of ataxia was 2 years; onset of falls, 6 years; dependence on a walking aid, 15 years; and death, 21 years. Preliminary data on life expectancy are variable, with a range from 5 to 25 years.

Molecular and imaging correlates of the fragile X-associated tremor/ataxia syndrome

OBJECTIVES

To assess changes in regional brain volumes associated with the fragile X-associated tremor/ataxia syndrome (FXTAS) and the molecular correlates of these changes.

METHODS

We administered molecular, MRI, and neurocognitive tests to 36 male premutation carriers (ages 51 to 79), 25 affected and 11 unaffected with FXTAS, and to 21 control subjects of similar age and education.

RESULTS

We found differences among the three groups in whole brain, cerebrum, cerebellum, ventricular volume, and whole-brain white matter hyperintensity, with the affected group showing significantly more pathology than the control and unaffected groups. Brainstem volume was significantly smaller in the unaffected group vs controls but did not differ from the affected group. Within the premutation sample, CGG repeat length correlated with reductions in IQ and cerebellar volume and increased ventricular volume and whole-brain white matter hyperintensity.

CONCLUSIONS

The current findings, coupled with recent evidence linking the degree of neuropathology (numbers of intranuclear inclusions) to the size of the premutation allele, provide evidence that the neurodegenerative phenotype in the fragile X-associated tremor/ataxia syndrome is a consequence of the CGG repeat expansion.

Effect of CX516, an AMPA-modulating compound, on cognition and behavior in fragile X syndrome: a controlled trial

A Phase II, 4-week randomized, double-blind, placebo-controlled clinical trial was conducted to evaluate the safety and efficacy of the Ampakine compound CX516 as a potential treatment for the underlying disorder in fragile X syndrome (FXS). After baseline screening, subjects with FXS (n = 49) underwent a 1-week placebo lead-in and then were randomized to study drug or placebo for a 4-week period. Cognitive and behavioral outcome measures were administered prior to treatment, at the end of treatment, and 2 weeks posttreatment. There were minimal side effects, no significant changes in safety parameters, and no serious adverse events. There was a 12.5% frequency of allergic rash in the CX516 group and 1 subject developed a substantial rash. There was also no significant improvement in memory, the primary outcome measure, or in secondary measures of language, attention/executive function, behavior, and overall functioning in CX516-treated subjects compared to placebo. This study did demonstrate that many outcome measures were reproducible in this test-retest setting for the FXS population, yet some were too difficult or variable. Adult subjects with FXS were able to complete an intensive clinical trial, and some valid outcome measures were identified for future FXS trial design. Problems with potency of CX516 in other studies have suggested dosing may have been inadequate for therapeutic effect and thus it remains unclear whether modulation of AMPA-mediated neurotransmission is a viable therapeutic strategy for the treatment of FXS.

A phase II trial of epirubicin (E), estramustine phosphate (EP), and celecoxib (C) as second line treatment of patients (pts) with hormone resistant prostate cancer (HRPC)

14567

Background: Celecoxib, epirubicin, and estramustine phosphate affect prostate cancer cells through different mechanisms. All three could be synergistic. We studied the effects of this combination on PSA, response, toxicity and survival in pts with HRPC. Methods: Pts after progression from first line taxane-based chemotherapy with rising PSA and radiographic progression were eligible. Treatment was E30 mg/m2 iv on day 1 and 8 of each 4 week cycle; EP 280 mg po bid daily × 3 days every wk × 2 followed by 2 wks rest; C 400 mg po bid daily for 28 days. All pts were assessed for response every 2 cycles. Dose modifications for hematologic and hepatorenal toxicity were made. RECIST criteria and PSA decline>50% were used to define response. Results: Sixteen pts enrolled, and 13 are evaluable for toxicity and response. Two withdrew before treatment and one for toxicity. The Median (M) age was 71.5 yrs (59–87), ECOG PS 1 (0–1), Gleason score 7 (4–9), LDH 172 (131–244), Hgb 11.1 (8.8–11.9), PSA 75 (6–814). Pts received M 4 cycles (2–10). Nine (69%) pts had soft tissue and 12 (92%) pts had bone metastases. For radiographic response, 11 pts were evaluable; 6 had stable disease and 2 had complete response by CT. Two pts had response by bone scan. Nine (69%) pts had PSA response. The M survival was 441 days (10–995). There were 5 SAE - DVT, diarrhea, bowel obstruction, cord compression and myocardial infarction. There was good renal and cardiac tolerance. Conclusions: This combination was safe and showed good and durable response as a second line regimen.

[Table: see text]

Combination therapy with docetaxel (D) and celecoxib (C) in patients (pts) with hormone resistant prostate cancer (HRPC)

14519

Background: Cox-2 expression is an independent predictor of survival and is over expressed in 89.3% of pts with HRPC. Cox-2 expression has angiogenic and cytoprotective effects. Its suppression could lead to angiogenesis inhibition and increase chemotherapy sensitivity. D in low doses and C are angiogenesis inhibitors. The main objectives were to study the effects on PSA, time to progression (TTP), toxicity and survival. Methods: In a two stage, phase II trial designed for 66 pts, 30 pts with HRPC and evidence of biochemical and radiographic progression were treated with D 30 mg/m2 IV/wk for 3 wks and C 400 mg po bid for 4 wks of each cycle. Response evaluation after every two cycles was made. RECIST criteria and PSA reduction by >50% for biochemical response were used. Independent safety monitoring for renal (R) and cardiovascular (CV) toxicity were made. Results: Thirty (30) evaluable pts received minimum of 2 cycles, median (M) 4.5 (range 2–8). The M age was 74 yr (55–94), ECOG PS 1 (0–2), Hb 11.8 g/dl (8.6–14.6), and PSA 92.5 ng/dl (15.3–4192). Metastases were present in 24 pts (80%) by bone scan and 25 pts (83.3%) by CT scan. Twelve (12) pts (40%) had PSA response of >50% and 4 pts (13.3%) had PSA normalization. By CAT scan, 3 pts (10%) had CR, 5 pts (16.7%) had PR, and 12 pts (40%) had SD. By bone scan 1 pt (4.8%) had a major response. The M TTP by PSA was 3.65 mos (0.87–12.0). With 27% pts still alive, the M survival was 10.9 mos (3.0– 30.7+), with 95% CI for the mean (9.3–15.2). One pt (3.3%) withdrew due to abdominal discomfort, 2 pts (6.6%) had grade III diarrhea and 1 pt (3.3%) had grade III nail toxicity. Conclusions: 66.7% pts had soft tissue response (CR+PR+SD), and 13.3% pts had PSA normalization. Safety analysis for R and CV toxicity demonstrated excellent safety of this regimen. Considering the unfavorable prognostic indicators of this population the MST of 10.9 mos indicates the activity of this combination.

[Table: see text]

Quality of life (QOL) in patients (Pts) with hormone resistant prostate cancer (HRPC) treated with docetaxel (D) and celecoxib (C)

18598

Background: The impact of chemotherapy on QOL for pts with HRPC is not well described. Thirty patients(30) participated in a trial of D and C(Kasimis et al, submitted ASCO 2006). The objectives for this companion study were to study QOL outcomes with the FACT instrument including the Prostate subscale(FP) and utility from the EQ5D. Methods: In a phase II trial, 30 pts with progressive HRPC were treated with D and C for 4 wks in each cycle. Response evaluation was made by RECIST criteria and PSA reduction by >50% for biochemical response every 2 cycles. Patients completed the FACT and EQ5D instruments at the beginning of every cycle. We analyzed the FACT subscales with different statistical approaches, and compared FACT and utility for responders and non responders. Results: All 30 pts accrued were evaluable for toxicity and response. Thirty (30) pts received a minimum of 2 cycles, median (M) 4.5 (range 2–8). The M age was 74 yr (55–94), ECOG PS 1 (0–2). For 19 pts, the baseline mean score for the FACT P was 29, Standard Deviation 10. The Cronbach’s Coefficient was 0.83. The FACT Physical Well Being (PWB) correlated with the EQ5D utility score 0.76 (p < .0003), as did the Functional Well Being (FWB) 0.67 (p < .003) and FACT P 0.62 (p < .006). The FACT PWB, EWB, FP, Treatment Outcome Index, and EQ5D Utility differed significantly between responders and non responders by radiographic parameters, alpha = 0.1. The results for PSA reduction >50% are similar. Conclusions: The FACT Prostate subscale has good psychometric properties, correlates with EQ5D utility measure, and also with responder status by radiography and PSA.

[Table: see text]

Initial diagnoses given to persons with the fragile X associated tremor/ataxia syndrome (FXTAS)

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a newly described disorder that occurs in premutation carriers of the fragile X mental retardation 1 (FMR1) gene. Fifty-six patients with FXTAS were given 98 prior diagnoses: most were in the categories of parkinsonism, tremor, ataxia, dementia, or stroke. Data from this study and others were used to develop guidelines for FMR1 diagnostic testing for FXTAS.

Psychiatric phenotype of the fragile X-associated tremor/ataxia syndrome (FXTAS) in males: newly described fronto-subcortical dementia

OBJECTIVE

The authors describe and quantify the neuropsychiatric symptoms present in a cohort of males with the fragile X mental retardation 1 (FMR1) premutation allele who have developed fragile X-associated tremor/ataxia syndrome (FXTAS).

METHOD

Fourteen male carriers of the FMR1 premutation who had clinical manifestations of the FXTAS syndrome and 14 age- and education-matched controls were assessed with the Neuropsychiatric Inventory (NPI), formal cognitive testing, and genetic analysis.

RESULTS

Males with FXTAS had significantly higher total NPI scores (p < .004) and significantly higher scores on the agitation/aggression (p < .004), depression (p < .004), apathy (p < .004), disinhibition (p < .004), and irritability (p < .004) scales, compared with controls. Cognitive performances on the Mini-Mental State Examination did not correlate with severity of symptoms on the NPI.

CONCLUSIONS

The neuropsychiatric manifestations of FXTAS, based on this preliminary report, appear to cluster as a fronto-subcortical dementia. Clinicians encountering patients with clinical dementia with motor symptoms suggesting FXTAS should consider genetic testing to determine whether the patient's dementia syndrome is secondary to a fragile X premutation carrier status.

Reactive oxygen species-induced phosphorylation of p53 on serine 20 is mediated in part by polo-like kinase-3

Upon exposure of cells to hydrogen peroxide (H(2)O(2)) phosphorylation of p53 was rapidly induced in human fibroblast GM00637, and this phosphorylation occurred on serine 9, serine 15, serine 20, but not on serine 392. In addition, H(2)O(2)-induced phosphorylation of p53 was followed by induction of p21, suggesting functional activation of p53. Induction of phosphorylation of p53 on multiple serine residues by H(2)O(2) was caffeine-sensitive and blocked in ATM(-/-) cells. Polo-like kinase-3 (Plk3) activity was also activated upon H(2)O(2) treatment, and this activation was ATM-dependent. Recombinant His(6)-Plk3 phosphorylated glutathione S-transferase (GST)-p53 fusion protein but not GST alone. When phoshorylated in vitro by His(6)-Plk3, but not by the kinase-defective mutant His6-Plk3(K52R), GST-p53 was recognized by an antibody specifically to serine 20-phosphorylated p53, indicating that serine 20 is an in vitro target of Plk3. Also serine 20-phosphorylated p53 was coimmunoprecipitated with Plk3 in cells treated with H(2)O(2). Furthermore, although H(2)O(2) strongly induced serine 15 phosphorylation of p53, it failed to induce serine 20 phosphorylation in Plk3-dificient Daudi cells. Ectopic expression of a Plk3 dominant negative mutant, Plk3(K52R), in GM00637 cells suppressed H(2)O(2)-induced serine 20 phosphorylation. Taken together, our studies strongly suggest that the oxidative stress-induced activation of p53 is at least in part mediated by Plk3.

Survival of patients who had salvage castration after failure on bicalutamide monotherapy for stage (D2) prostate cancer

Patients with hormone-naive stage D2 prostate cancer often benefit from castration. This treatment, however, frequently produces many unacceptable physical and psychological side effects, especially in younger and sexually active patients. Bicalutamide is an oral antiandrogen with excellent tolerance and preservation of sexual function. Three institutions participated in phase II and III trials of bicalutamide monotherapy (50 mg daily) as primary therapy in hormone-naive patients with stage D2 prostate cancer. Upon bicalutamide failure, all patients underwent castration and were followed until death. Fifty-four patients received bicalutamide 50 mg orally once a day. One patient (2%) had complete response, 9 patients (17%) had partial response, and 27 patients (50%) had stable disease. Seventeen patients (31%) had progressive disease. The median time to bicalutamide failure was 47.4 weeks, 70.5 weeks for the responders vs. 25.4 weeks for the nonresponders (p < 0.001). The median survival time after the sequential use of bicalutamide and castration was 119.2 weeks for all 54 patients, 162.0 weeks for the responders, and 73.5 weeks for nonresponders (p < 0.0001). The median survival time after initiation of castration was 71.1 weeks for all 54 patients, 91.4 weeks for bicalutamide responders, and 42.1 weeks for nonresponders (p < 0.01). In hormone-naive patients with stage D2 prostate cancer, sequential treatment with bicalutamide monotherapy followed by castration upon failure may produce survival time within the range reported for initial treatment with castration. Thus, considering the favorable quality of life profile of bicalutamide, further studies are needed to define the role of sequential hormonal therapy in younger sexually active patients.

MyoD functions as a transcriptional repressor in proliferating myoblasts

The myogenic basic helix-loop-helix (myo-bHLH) proteins are a family of transcriptional regulators expressed in myoblasts and differentiated skeletal muscle. Ectopic expression of myo-bHLH regulators transdetermines some fibroblast cell lines into myoblasts, which exit the cell cycle and differentiate into skeletal muscle when cultured in low mitogen medium. While members of the myo-bHLH family have been shown to function as transcriptional activators in differentiating muscle, the molecular basis of their function in proliferating myoblasts has not been elucidated. In this report, we present evidence that MyoD functions as a transcriptional repressor in myoblasts. We show that transcription from a cyclin B1 promoter construct is repressed in proliferating myoblasts and that repression is mediated by a pair of MyoD binding sites. We also show that transcription from the cyclin B1 promoter is repressed in proliferating C3H10T1/2 cells by ectopic expression of MyoD. These results demonstrate that MyoD can repress transcription of specific genes in proliferating cells, a novel function that may be important to maintenance of the myogenic phenotype and to cell cycle regulation in myoblasts.