The STRAT-PARK cohort: A personalized initiative to stratify Parkinson's disease

The STRAT-PARK initiative aims to provide a platform for stratifying Parkinson's disease (PD) into biological subtypes, using a bottom-up, multidisciplinary biomarker-based and data-driven approach. PD is a heterogeneous entity, exhibiting high interindividual clinicopathological variability. This diversity suggests that PD may encompass multiple distinct biological entities, each driven by different molecular mechanisms. Molecular stratification and identification of disease subtypes is therefore a key priority for understanding and treating PD. STRAT-PARK is a multi-center longitudinal cohort aiming to recruit a total of 2000 individuals with PD and neurologically healthy controls from Norway and Canada, for the purpose of identifying molecular disease subtypes. Clinical assessment is performed annually, whereas biosampling, imaging, and digital and neurophysiological phenotyping occur every second year. The unique feature of STRAT-PARK is the diversity of collected biological material, including muscle biopsies and platelets, tissues particularly useful for mitochondrial biomarker research. Recruitment rate is ∼150 participants per year. By March 2023, 252 participants were included, comprising 204 cases and 48 controls. STRAT-PARK is a powerful stratification initiative anticipated to become a global research resource, contributing to personalized care in PD.

Quantifying Brain Iron in Hereditary Hemochromatosis Using R2* and Susceptibility Mapping

BACKGROUND AND PURPOSE

Brain iron dyshomeostasis is increasingly recognized as an important contributor to neurodegeneration. Hereditary hemochromatosis is the most commonly inherited disorder of systemic iron overload. Although there is an increasing interest in excessive brain iron deposition, there is a paucity of evidence showing changes in brain iron exceeding that in healthy controls. Quantitative susceptibility mapping and R2* mapping are established MR imaging techniques that we used to noninvasively quantify brain iron in subjects with hereditary hemochromatosis.

MATERIALS AND METHODS

Fifty-two patients with hereditary hemochromatosis and 47 age- and sex-matched healthy controls were imaged using a multiecho gradient-echo sequence at 3T. Quantitative susceptibility mapping and R2* data were generated, and regions within the deep gray matter were manually segmented. Mean susceptibility and R2* relaxation rates were calculated for each region, and iron content was compared between the groups.

RESULTS

We noted elevated iron levels in patients with hereditary hemochromatosis compared with healthy controls using both R2* and QSM methods in the caudate nucleus, putamen, pulvinar thalamus, red nucleus, and dentate nucleus. Additionally, the substantia nigra showed increased susceptibility while the thalamus showed an increased R2* relaxation rate compared with healthy controls, respectively.

CONCLUSIONS

Both quantitative susceptibility mapping and R2* showed abnormal levels of brain iron in subjects with hereditary hemochromatosis compared with controls. Quantitative susceptibility mapping and R2* can be acquired in a single MR imaging sequence and are complementary in quantifying deep gray matter iron.

Brain iron deposition and movement disorders in hereditary haemochromatosis without liver failure: A cross-sectional study

BACKGROUND AND PURPOSE

Hereditary haemochromatosis (HH) is the most common inherited disorder of systemic iron excess in Northern Europeans. Emerging evidence indicates that brain iron overload occurs in HH. Despite this observation, there is a paucity of literature regarding central neurological manifestations, in particular movement disorders, in HH. The current study documents deep gray matter (DGM) nuclei iron deposition, movement disorders, and clinicoradiological correlations in HH without liver failure.

METHODS

This is a cross-sectional study. Consecutive subjects with HFE-haemochromatosis without liver disease were recruited from an outpatient gastroenterology clinic. Age- and sex-matched healthy controls (HCs) were enrolled. Iron content in individual DGM nuclei was measured as mean susceptibility on magnetic resonance imaging using quantitative susceptibility mapping-based regions of interest analysis. Occurrence and phenotype of movement disorders were documented and correlated with patterns of DGM nuclei iron deposition in subjects with HH.

RESULTS

Fifty-two subjects with HH and 47 HCs were recruited. High magnetic susceptibility was demonstrated in several DGM nuclei in all HH subjects compared to HCs. Thirty-five subjects with HH had movement disorders. Magnetic susceptibility in specific DGM nuclei correlated with individual movement disorder phenotypes. Serum ferritin, phlebotomy frequency, and duration were poor predictors of brain iron deposition.

CONCLUSIONS

Abnormal brain iron deposition can be demonstrated on imaging in all subjects with HH without liver failure. A significant proportion of these subjects manifest movement disorders. Peripheral iron measurements appear not to correlate with brain iron deposition. Therefore, routine neurological examination and quantitative brain iron imaging are recommended in all subjects with HH.

Clinical, surgical, and pathological findings in client-owned rabbits with histologically confirmed appendicitis: 19 cases (2015-2019)

OBJECTIVE

To report clinical, surgical, and pathological findings in client-owned rabbits with histologically confirmed appendicitis.

ANIMALS

19 rabbits.

PROCEDURES

Medical records for client-owned rabbits that had a histologic diagnosis of appendicitis were reviewed.

RESULTS

Median age of the rabbits at presentation was 24.0 months (range, 4 to 84 months). Seventeen cases occurred during the summer and fall seasons. Decreased appetite (17/19 rabbits), abnormal rectal temperature (hyperthermia, 9/16 rabbits; hypothermia, 4/16 rabbits), hypocalcemia (8/11 rabbits), and hypoglycemia (7/15 rabbits) were common signs. Abdominal ultrasonography and CT findings were suggestive of appendicitis in 6 of 8 rabbits and in 1 of 2 rabbits, respectively. Of the 6 rabbits that received medical treatment, 3 died at 48 hours, 1 died at 24 hours after hospitalization, and 1 died at 10 days after presentation; 1 rabbit was alive at 1,030 days after presentation. Of the 8 rabbits that underwent appendectomy, 3 died before discharge from the hospital and 1 died 113 days after surgery; 4 rabbits were alive at 315, 334, 1,433, and 1,473 days after presentation. The remaining 5 rabbits either died or were euthanized before treatment could be instituted. In each of the 19 rabbits, the appendix had evidence of severe inflammation with mucosal ulceration, heterophilic inflammation, and necrotic debris.

CLINICAL RELEVANCE

For rabbits with decreased appetite and an apparently painful abdomen, hyperthermia, hypocalcemia, or hypoglycemia, appendicitis should be considered as a differential diagnosis. Further comparisons of medical and surgical treatments are required to establish treatment recommendations for rabbits with appendicitis.

Surgical treatment and outcome of complete unilateral urinary tract duplication in a dog

OBJECTIVE

To report the surgical technique and outcome for correction of complete unilateral duplication of the left urinary tract in a dog.

ANIMALS

One 7-month-old entire male Jack Russell terrier.

STUDY DESIGN

Case report METHODS: A dog was referred for investigation because of urinary incontinence (UI), preputial irritation (pruritus), diphallia, and cryptorchidism. Computed tomography including urethrographic studies revealed a left duplex kidney, double ectopic left ureters, and a duplex urinary bladder comprising two halves separated by a median septum, each of which emptied into a separate urethra which coursed through separate penises. The left testis was abdominally retained. The right upper urinary tract was considered normal, and the right testis was within the scrotum. Left sided ureteronephrectomy was performed, the median bladder septum was ablated, and the left urethra was ligated. The left penis was partially amputated, and the dog was castrated.

RESULTS

Urinary incontinence was improved but persisted after surgery. After repeat imaging, revision surgery was performed 3 months later in which the distal stumps of the (left) ectopic ureters were found to be filling with urine from the right urethra. Urinary incontinence resolved after resection of these ureteric stumps from the prostate and complete transection of the left urethra.

CONCLUSION

Extensive surgery with resection and correction of urinary tract duplication was successful in resolving UI in this case. Urogenital duplication should be considered a rare cause of UI. The presence of external congenital deformity (eg, diphallia) should alert clinicians to the possibility of significant concurrent internal abnormalities.

Bilateral bronchial stent deployment for palliative treatment of a compressive intrathoracic mass in a cat

Case summary

Bronchial stents may be useful to relieve clinical signs of extraluminal compression. Herein we describe a case which, to our knowledge, is the first cat where bilateral bronchial stents have been used clinically. Respiratory signs of principal bronchial compression were alleviated after the stent procedure. Minor complications occurred, specifically: severe hypoxia during stent deployment; a transient, self-limiting postoperative pneumothorax possibly associated with ventilation-induced lung injury; bronchopneumonia (possibly pre-existing); and transient worsening of cough postoperatively. Stents were well- tolerated long- term. The cat was euthanased at 44 weeks post-stent procedure, owing to clinical signs of regurgitation, seemingly related to oesophageal dysfunction associated with tumour invasion.

Relevance and novel information

In this case, it appeared that bronchial stents were feasible and the procedure was associated with long-term improvement in respiratory signs related to extraluminal bronchial compression.

Collaborating to Compete: Blood Profiling Atlas in Cancer (BloodPAC) Consortium

The cancer community understands the value of blood profiling measurements in assessing and monitoring cancer. We describe an effort among academic, government, biotechnology, diagnostic, and pharmaceutical companies called the Blood Profiling Atlas in Cancer (BloodPAC) Project. BloodPAC will aggregate, make freely available, and harmonize for further analyses, raw datasets, relevant associated clinical data (e.g., clinical diagnosis, treatment history, and outcomes), and sample preparation and handling protocols to accelerate the development of blood profiling assays.

Terminate lung cancer (TLC) study-A mixed-methods population approach to increase lung cancer screening awareness and low-dose computed tomography in Eastern Kentucky

For low dose CT lung cancer screening to be effective in curbing disease mortality, efforts are needed to overcome barriers to awareness and facilitate uptake of the current evidence-based screening guidelines. A sequential mixed-methods approach was employed to design a screening campaign utilizing messages developed from community focus groups, followed by implementation of the outreach campaign intervention in two high-risk Kentucky regions. This study reports on rates of awareness and screening in intervention regions, as compared to a control region.

Study design, intervention, and baseline characteristics of a group randomized trial involving a faith-based healthy eating and physical activity intervention (Walk by Faith) to reduce weight and cancer risk among overweight and obese Appalachian adults

BACKGROUND

Increased prevalence of overweight and obesity among Appalachian residents may contribute to increased cancer rates in this region. This manuscript describes the design, components, and participant baseline characteristics of a faith-based study to decrease overweight and obesity among Appalachian residents.

METHODS

A group randomized study design was used to assign 13 churches to an intervention to reduce overweight and obesity (Walk by Faith) and 15 churches to a cancer screening intervention (Ribbons of Faith). Church members with a body mass index (BMI) ?25 were recruited from these churches in Appalachian counties in five states to participate in the study. A standard protocol was used to measure participant characteristics at baseline. The same protocol will be followed to obtain measurements after completion of the active intervention phase (12months) and the sustainability phase (24months). Primary outcome is change in BMI from baseline to 12months. Secondary outcomes include changes in blood pressure, waist-to-hip ratio, and fruit and vegetable consumption, as well as intervention sustainability.

RESULTS

Church members (n=664) from 28 churches enrolled in the study. At baseline 64.3% of the participants were obese (BMI?30), less than half (41.6%) reported regular exercise, and 85.5% reported consuming less than 5 servings of fruits and vegetables per day.

CONCLUSIONS

Church members recruited to participate in a faith-based study across the Appalachian region reported high rates of unhealthy behaviors. We have demonstrated the feasibility of developing and recruiting participants to a faith-based intervention aimed at improving diet and increasing exercise among underserved populations.

Risk factors for acute and overuse sport injuries in Swedish children 11 to 15 years old: What about resistance training with weights?

To determine the 1-year self-reported incidence of overuse and traumatic sport injuries and risk factors for injuries in children participating in a summer sports camp representing seven different sports. 4363 children, 11 to 15 years old participating in a summer camp in seven different sports answered a questionnaire. Injury in this cross-sectional study was defined as a sport-related trauma or overload leading to pain and dysfunction preventing the person from participation in training or competition for at least 1 week. A number of risk factors for injury were investigated such as sex, age, number of hours spent on training in general, and on resistance training with weights. Nearly half [49%, 95% confidence interval (CI) 48-51%] of the participants had been injured as a result of participation in a sport during the preceding year, significantly more boys than girls (53%, 95% CI 50-55% vs 46%, 95% CI 43-48%; P < 0.001). Three factors contributed to increased incidence of sport injuries: age, sex, and resistance training with weights. Time spent on resistance training with weights was significantly associated with sport injuries in a logistic regression analysis. In children age 11 to 15 years, the risk of having a sport-related injury increased with age and occurred more often in boys than in girls. Weight training was the only modifiable risk factor that contributed to a significant increase in the incidence of sport injuries.

Massively parallel tumor multigene sequencing to evaluate response to panitumumab in a randomized phase III study of metastatic colorectal cancer

PURPOSE

To investigate whether EGF receptor (EGFR) pathway mutations predicted response to monotherapy with panitumumab, an anti-EGFR monoclonal antibody, in a randomized phase III study of metastatic colorectal cancer.

EXPERIMENTAL DESIGN

Using massively parallel multigene sequencing, we analyzed 320 samples for 9 genes, with multigene sequence data from 288 (90%) samples.

RESULTS

Mutation rates were: KRAS (45%), NRAS (5%), BRAF (7%), PIK3CA (9%), PTEN (6%), TP53 (60%), EGFR (1%), AKT1 (<1%), and CTNNB1 (2%). In the randomized study and open-label extension, 22 of 138 (16%) wild-type KRAS (codons 12/13/61) patients versus 0 of 103 mutant KRAS (codons 12/13) patients had objective responses. Of 6 mutant KRAS (codon 61) patients, 1 with a Q61H mutation achieved partial response during the extension. Among wild-type KRAS (codons 12/13/61) patients, 0 of 9 patients with NRAS mutations, 0 of 13 with BRAF mutations, 2 of 10 with PIK3CA mutations, 1 of 9 with PTEN mutations, and 1 of 2 with CTNNB1 mutations responded to panitumumab. No patients responded to best supportive care alone. Panitumumab treatment was associated with longer progression-free survival (PFS) among wild-type KRAS (codons 12/13/61) patients [HR, 0.39; 95% confidence interval (CI), 0.28-0.56]. Among wild-type KRAS patients, a treatment effect for PFS favoring panitumumab occurred in patients with wild-type NRAS (HR, 0.39; 95% CI, 0.27-0.56) and wild-type BRAF (HR, 0.37; 95% CI, 0.24-0.55) but not mutant NRAS (HR, 1.94; 95% CI, 0.44-8.44).

CONCLUSIONS

These results show the feasibility and potential clinical use of next-generation sequencing for evaluating predictive biomarkers.

Achieving health for a lifetime: a community engagement assessment focusing on school-age children to decrease obesity in Durham, North Carolina

BACKGROUND

Obesity is a prominent problem in the United States and in North Carolina. One way of combating it is with community-engaged interventions that foster collaboration between health-oriented organizations and community residents.

PURPOSE

Our purpose was to assemble a multifaceted group in Durham, North Carolina, to identify factors affecting obesity-related lifestyle behaviors; assess policies, resources, and the population's perception of the problem of obesity; and develop plans to improve health outcomes related to obesity.

METHODS

A team consisting of more than 2 dozen partners was assembled to form Achieving Health for a Lifetime (AHL) in order to study and address obesity in the community, initially focusing on elementary school-age children. The team developed a resource guide by collecting information by telephone interviews of provider organizations; geospatial resource maps were created using high-resolution geographic information systems, Duke's Data Support Repository, and county and city records; and focus groups were conducted using the nominal group technique.

RESULTS

The AHL team, in collaboration with 2 other teams focused on diabetes and cardiovascular disease, identified 32 resources for diabetes, 20 for obesity, and 13 for cardiovascular disease. Using Geographic Information Systems (GIS), the team identified an area of Durham that had only 1 supermarket, but 34 fast-food restaurants and 84 convenience stores.

LIMITATIONS

The focus on particular neighborhoods means that the information obtained might not pertain to all neighborhoods.

CONCLUSION

The AHL team was able to assemble a large community partnership in Durham that will allow the members of the community to continue to work toward making residents healthier. Communities facing similar challenges can learn from this experience.

Phase 1b study of dulanermin (recombinant human Apo2L/TRAIL) in combination with paclitaxel, carboplatin, and bevacizumab in patients with advanced non-squamous non-small-cell lung cancer

PURPOSE

To determine the safety, pharmacokinetics (PK), and maximum-tolerated dose (MTD) up to a prespecified target dose of dulanermin in combination with paclitaxel, carboplatin, and bevacizumab (PCB) in patients with previously untreated, nonsquamous, stage IIIb (with pleural effusion)/IV or recurrent non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

In this phase 1b study, patients (n = 24) received PCB on day 1 of each 21-day cycle then dulanermin at 4 or 8 mg/kg/d for 5 consecutive days or 15 or 20 mg/kg/d for 2 consecutive days per assigned treatment cohort. Incidence of dose-limiting toxicities (DLTs), adverse events, and antidulanermin antibodies were assessed. PK parameters were recorded for each agent. Tumor response was measured by modified Response Evaluation Criteria in Solid Tumors.

RESULTS

Twenty-four patients received at least one dose of dulanermin plus PCB, six in each treatment cohort. There were no DLTs. An MTD was not reached, and the drug combination was well tolerated. Treatment-emergent adverse events were generally as expected for the PCB regimen. Adverse events attributed to dulanermin were grade 1/2; no significant hepatotoxicity occurred. There was minimal impact of PCB on the PK of dulanermin. There was one confirmed complete response and 13 confirmed partial responses. The overall response rate was 58% (95% CI, 37 to 78). Median progression-free survival was 7.2 months (95% CI, 4.7 to 10.3).

CONCLUSION

Dulanermin plus PCB was well tolerated with no occurrence of DLTs and demonstrated antitumor activity in this patient population. Dulanermin at 8 mg/kg/d for 5 days and 20 mg/kg/d for 2 days every 3 weeks in combination with PCB is being studied in a phase II trial.

Phase II study of docetaxel (D) plus bevacizumab (B) in Her/2 negative metastatic breast carcinoma (MBC)

13047

Background: Taxol+Bevacizumab (B) has clinical activity in Her/2 negative chemotherapy naive MBC with a PFS (11.4 mo), RR (29.9%), and OS (28.4 mo). We are conducting a single arm Phase 2 trial to assess the efficacy of Docetaxel (D)+B. Primary endpoint: time to progression. Secondary endpoints: response rate (CR + PR), response duration, overall survival and safety. Methods: Eligibility criteria: MBC with no prior therapy; Her/2 negative by FISH, ECOG PS 0 or 1; measurable disease by RECIST, Hgb ≥ 9 g/dL, ANC ≥ 1.5 × 109/L, Platelet count ≥ 100 × 109/L, Creatinine ≤ 2.0 mg/dL, Total bilirubin ≤ 1.0 × upper limit of normal, no CNS metastasis, no MI or stroke within 6 mo, no GI perforation, no major surgery within 28 d, and no bleeding diathesis or coagulopathy. Pts receive B 15 mg/kg IV and D 75 mg/m2 IV Q 3 wk. Response assessed radiographically Q 3 cycles. Treatment is until disease progression or unacceptable toxicity. Results: Since Apr 2005, 43 of the planned 75 pts have been enrolled. 21 pts have had at least one assessment resulting in approximately 40% response rate. Common Gr3/4 AE’s have been neutropenia, febrile neutropenia, hypertension. Gr3 LVEF decline seen in one pt. No treatment related deaths occurred. Conclusions: D+ B is well tolerated, with no new safety concerns and manageable toxicities. D+B appears active in MBC. Updated efficacy and safety data will be presented. Study supported by Genentech, Inc. San Francisco, CA.

No significant financial relationships to disclose.

Results of Two Open-Label, Multicenter Phase II Studies of Docetaxel, Platinum Salts, and Trastuzumab in HER2-Positive Advanced Breast Cancer

BACKGROUND

Preclinical data indicate that docetaxel, platinum salts, and the combination of both drugs are highly synergistic with the anti-HER2 antibody trastuzumab. The University of California at Los Angeles-Oncology Research Network (UCLA-ORN) and the Breast Cancer International Research Group (BCIRG) have conducted two phase II studies to evaluate docetaxel and trastuzumab in combination with either cisplatin or carboplatin for the treatment of women with advanced breast cancer that overexpresses HER2.

METHODS

Each study enrolled 62 patients with HER2-overexpressing tumors. Patients received a median of six cycles of docetaxel at 75 mg/m2 of body surface area and cisplatin (BCIRG 101 study) at 75 mg/m2 or carboplatin (UCLA-ORN study) at AUC = 6 mg/mL. min given on day 1 and then every 21 days. Trastuzumab was given on day 1, cycle 1 (4 mg/kg) and then continued weekly at 2 mg/kg for 1 year or until disease progression. Tumor measurements were obtained at baseline, after three cycles of chemotherapy, and then every 3 months. HER2 gene amplification was determined by fluorescence in situ hybridization.

RESULTS

Patient characteristics were comparable between trials with the exception that 15% of the patients in the UCLA-ORN study had received previous adjuvant taxane therapy. Both regimens were well tolerated, with manageable toxicities. Hematologic toxicities were more frequent in patients in the UCLA-ORN study than in patients in the BCIRG 101 study, whereas the reverse pattern was observed for non-hematologic toxicities. One patient in each study developed reversible congestive heart failure. Responses were observed in 49 of 62 patients in the BCIRG 101 study (overall response rate = 79%, 95% confidence interval [CI] = 66% to 89%) and in 34 of 59 evaluable patients in the UCLA-ORN study (overall response rate = 58%, 95% CI = 44% to 70%). Median times to progression were 9.9 months (95% CI = 8.3 to 13.1 months) and 12.7 months (95% CI = 8.6 to 15.5 months) for patients in the BCIRG 101 and UCLA-ORN studies, respectively. Overall response rates were higher and median time to progression was longer in the subset of patients whose tumors harbored HER2 gene amplification.

CONCLUSION

Combinations of docetaxel, a platinum salt, and trastuzumab are feasible and active in patients with advanced breast cancers that overexpress HER2. The BCIRG is conducting ongoing randomized studies of the three-drug combination in both the metastatic and adjuvant settings.

Phase III trial comparing granulocyte colony-stimulating factor to leridistim in the prevention of neutropenic complications in breast cancer patients treated with docetaxel/doxorubicin/cyclophosphamide: results of the BCIRG 004 trial

This randomized, double-blind, phase III trial compared granulocyte colony-stimulating factor (G-CSF; filgrastim) and leridistim (formerly myelopoietin), a chimeric dual agonist that binds both G-CSF and interleukin-3 receptors, for the prevention of neutropenic complications in patients with breast cancer receiving TAC (docetaxel/doxorubicin/cyclophosphamide) chemotherapy. Patients with metastatic (44%) or localized breast cancer (56%) were randomized to G-CSF 5 microg/kg subcutaneously (s.c.) daily (n = 135), leridistim 5 microg/kg s.c. daily (n = 139), or leridistim 10 microg/kg s.c. every other day alternating with placebo (n = 139). Following administration of TAC (docetaxel 75 mg/m2, doxorubicin 50 mg/m2, cyclophosphamide 500 mg/m2) on day 1, patients received growth factor beginning on day 2 until the postnadir absolute neutrophil count exceeded 1500 cells/ microL. Chemotherapy cycles were repeated every 21 days. The incidence of febrile neutropenia was 7% in the G-CSF arm, 19% in the daily leridistim arm (P = 0.003 for comparison with G-CSF) and 22% in the alternate-day leridistim arm (P < 0.001 for comparison with G-CSF). There was no significant difference between treatment arms in the cumulative percentage of patients experiencing grade 4 neutropenia at some point during therapy (85%-88%). However, grade 4 neutropenia occurred in 53% of cycles in the G-CSF cohort, 61% of cycles in the daily leridistim group (P = 0.063 for comparison with G-CSF), and 63% of cycles in the alternate-day leridistim group (P = 0.015 for comparison with G-CSF). We conclude that G-CSF is superior to leridistim in the prevention of febrile neutropenia in patients with advanced breast cancer receiving TAC chemotherapy. The up-front prophylactic use of G-CSF is a reasonable supportive therapy for patients treated with docetaxel/anthracycline-based combination chemotherapy.

Anastrozole in the management of breast cancer

Anastrozole (Arimidex, AstraZeneca) is a third-generation aromatase inhibitor which rapidly reduces oestradiol concentrations to below detectable levels. It is both potent and selective for the aromatase enzyme, with near-maximal suppression of serum oestrogens occurring at the clinical dose of 1 mg/day in postmenopausal women with advanced breast cancer. Anastrozole has also been shown to be a potent suppressor of intratumoural oestrogens, with responses comparable to those in serum. The results of two large, identically designed, randomised trials in postmenopausal women with advanced breast cancer who had progressed on tamoxifen showed that oral anastrozole 1 mg/day produced a statistically significant survival advantage over megestrol acetate 40 mg q.i.d. The median duration of survival was 26.7 months for anastrozole versus 22.5 months for megestrol acetate. Anastrozole was as well-tolerated as megestrol acetate, while weight gain was significantly increased in the megestrol acetate group compared with the anastrozole group. In another Phase III clinical trial involving 1021 postmenopausal women with advanced breast cancer, anastrozole showed a statistically significant advantage over tamoxifen in median time to progression in a combined analysis of 611 patients who were known to be oestrogen receptor- or progesterone receptor-positive. Anastrozole was as well-tolerated as tamoxifen, with a low rate of withdrawals (2%) due to drug-related adverse events. In addition, anastrozole was associated with fewer thromboembolic events and episodes of vaginal bleeding than tamoxifen. For women with hormone receptor-positive tumours who progress on tamoxifen, anastrozole is superior to megestrol acetate. In addition, anastrozole is a reasonable alternative to tamoxifen for first-line endocrine therapy of advanced breast cancer. Recent data confirm an emerging role for anastrozole as adjuvant therapy for primary breast cancer in postmenopausal patients. Anastrozole is also being investigated in the neoadjuvant setting.

Evidence for the use of chemotherapy in breast cancer

Several distinct historical phases mark the evolution of chemotherapy for breast cancer, including the introduction of single agents in the 1960s, the development of cyclophosphamide, methotrexate, and 5-fluorouracil (CMF)-based regimens in the 1970s, the evaluation of the anthracyclines in the 1980s, and the incorporation of the taxanes in the 1990s. The greatest benefit from the use of standard combination chemotherapy occurs in the adjuvant setting, where absolute improvements in overall survival on the order of 10% have been achieved. In contrast, advances have been more modest in the treatment of metastatic disease, and novel agents and regimens are required for further progress. Of the new cytotoxic drugs introduced in the past decade, the taxanes and capecitabine appear to be the most promising, and have demonstrated activity alone and in combination for the treatment of metastatic disease. The introduction of trastuzumab, an antibody directed against the HER2 receptor protein, heralded the birth of targeted molecular therapy against breast cancer. It is clear that in the near future the further evaluation of trastuzumab combinations and the development of additional molecular agents will propel clinical breast cancer research. One of the main challenges of the new era will be identifying and validating predictive factors so that therapy may be individualized based on tumor biology, rather than empirically selected.

Modulation of omega-3/omega-6 polyunsaturated ratios with dietary fish oils in men with prostate cancer

OBJECTIVES

The results of epidemiologic and animal studies support the role of a low-fat diet supplemented with omega-3 fatty acids contained in fish oil in preventing the development and progression of prostate cancer. As a first step in studying the role of a low-fat, fish oil-supplemented (LF/FOS) diet in a clinical setting, we conducted a prospective study in men with untreated prostate cancer to evaluate whether a 3-month dietary intervention affects the ratio of omega-3 to omega-6 fatty acids in plasma and gluteal fat. In addition, we evaluated the feasibility of studying cyclooxygenase-2 (COX-2) expression in serial prostate needle biopsy specimens before and after the diet.

METHODS

Nine men with untreated prostate cancer consumed an LF/FOS diet for 3 months. Plasma, gluteal adipose tissue, and prostate needle biopsy specimens were obtained from each patient before and after the intervention. The fatty acid compositions of the plasma and gluteal adipose tissue were determined by gas-liquid chromatography, and the COX-2 expression in the prostatic tissue specimens was determined by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTS

Short-term intervention with an LF/FOS diet caused a significant increase in the omega-3/omega-6 fatty acid ratio in plasma (P = 0.002) and gluteal adipose tissue (P = 0.002) in men with prostate cancer. The COX-2 expression in prostatic tissue was quantitated by RT-PCR in 7 of 9 patients, and COX-2 expression decreased in 4 of these 7 patients.

CONCLUSIONS

A short-term dietary intervention in men with prostate cancer leads to a significant increase in the omega-3/omega-6 fatty acid ratios in plasma and adipose tissue. The potential for this diet to prevent the development and progression of prostate cancer by way of altered COX-2 expression and prostaglandin production in prostatic tissue requires further study.

A multi-institutional phase ii study of SU101, a platelet-derived growth factor receptor inhibitor, for patients with hormone-refractory prostate cancer

In a multi-institutional Phase II trial, we evaluated the efficacy of a platelet-derived growth factor receptor (PDGF-r) inhibitor, SU101, in patients with hormonerefractory prostate cancer. The patients received a 4-day i.v. loading dose of SU101 at 400 mg/m(2) for 4 consecutive days, followed by 10 weekly infusions at 400 mg/m(2). The primary study end points were a decline in prostate-specific antigen (PSA) and a decrease in measurable tumor. Secondary end points were time to progression and an effect on pain as measured by the Brief Pain Survey. Expression of PDGF-r was examined in both metastatic and archival primary prostate tumor samples. Forty-four patients were enrolled at four centers. The median age was 72 years, the median PSA was 223 ng/ml, and 21 patients had at least one prior chemotherapy. Thirty-nine patients are evaluable for PSA, and three patients demonstrated a PSA decline >50% from baseline (55-99.9% decrease). The median time to progression was 90 days. Of 19 patients evaluable for measurable disease, 1 patient had a partial response. Nine of 35 evaluable patients had significant improvement in pain. The most frequent adverse events were asthenia (75%), nausea (55%), anorexia (50%), and anemia (41%). PDGF-r expression was detected in 80% of the metastases and 88% of primary prostate cancers. The results of this trial may warrant further clinical studies with other PDGF-r inhibitors.

Insulin-inducible changes in the relative ratio of PTP1B splice variants

The skeletal muscle activity of protein tyrosine phosphates 1B (PTP1B), a modulator of insulin and IGF-1 signaling, is reduced in obese nondiabetic subjects and in subjects with type 2 diabetes in comparison with leaner, nondiabetic controls. PTP1B mRNA, like many other signaling molecules, including the insulin receptor, is alternatively spliced. Since we have shown that the ratio of the insulin receptor splice variants is modulated by insulin in vitro and is related to insulin levels in vivo, we hypothesized that the relative ratios of the alternatively spliced PTP1B mRNA might also vary in humans in proportion to the degree of hyperinsulinemia. This was tested in 21 nondiabetic Pima Indians, a population at increased risk for obesity and type 2 diabetes. The relative ratio of the PTP1B splice variants was quantified using RT-PCR of total RNA extracted from fractionated monocytes. The ratio of the splice variants was positively correlated with fasting plasma insulin concentration (r = 0.757; P = 0.0001), 2-h plasma insulin concentration following an oral glucose tolerance test (r = 0.614; P = 0.01, n = 16), and percentage of body fat (r = 0.746; P = 0.0001). These data indicate that variability in the ratio of the two splice variants is due, in part, to in vivo levels of chronic hyperinsulinemia. This simple, noninvasive assay is therefore a potential biomarker for chronic hyperinsulinemia, similar to the HbAlc assay in use to monitor glucose management in diabetic patients.

In vitro and in vivo hematopoietic activities of Betafectin PGG-glucan

Betafectin PGG-glucan is a novel beta-(1,3)glucan that has broad-spectrum anti-infective activities without cytokine induction. Here we report that PGG-glucan also has both in vitro and in vivo hematopoietic activities. In vitro studies with bone marrow target cells from the C3H/HeN mouse revealed that although PGG-glucan alone had no direct effect on hematopoietic colony-forming cell (CFC) growth, when combined with granulocyte colony-stimulating factor (CSF) or granulocyte-macrophage CSF, it increased CFC numbers 1.5- to 2.0-fold over those obtained with CSFs alone. Bone marrow cells cultured for high-proliferative-potential CFCs in the presence of interleukin (IL)-1, IL-3, macrophage CSF, and stem cell factor (SCF), or cultured for erythroid burst-forming units in the presence of IL-3, SCF, and erythropoietin, also exhibited enhanced growth in the presence of PGG-glucan. The synergistic effect of PGG-glucan was specific and could be abrogated by anti-PGG-glucan antibody. The ability of PGG-glucan to modulate hematopoiesis in vivo was evaluated in myelosuppressed rodents and primates. C3H/HeN female mice were intravenously administered saline solution or PGG-glucan (0.5 mg/kg) 24 hours before the intraperitoneal administration of cyclophosphamide (200 mg/kg), and the recovery of bone marrow cellularity and granulocyte-macrophage progenitor cells was evaluated on days 4 and 8 after cyclophosphamide treatment. At both time points, enhanced hematopoietic recovery was observed in PGG-glucan-treated mice compared with saline-treated control mice. In a final series of in vivo experiments, we evaluated the ability of therapeutically administered PGG-glucan to enhance hematopoietic recovery in cyclophosphamide-treated cynomolgus monkeys. Monkeys received intravenous infusions of cyclophosphamide (55 mg/kg) on days 1 and 2, followed on days 3 and 10 by intravenous infusion of PGG-glucan (0.5, 1.0, or 2.0 mg/kg). Compared with those in saline-treated monkeys, accelerated white blood cell recovery and a reduction in the median duration of neutropenia were observed in PGG-glucan-treated monkeys. These studies illustrate that PGG-glucan has both in vitro and in vivo hematopoietic activities and that this agent may be useful in the prevention and/or treatment of chemotherapy-associated myelosuppression.

Neurite growth patterns leading to functional synapses in an identified embryonic neuron

We explored the relationship between neurite outgrowth and the onset of synaptic activity in the central neuropil of the leech embryo in vivo. To follow changes in early morphology and the onset of synaptic activity in the same identified neuron, we obtained whole-cell patch-clamp recordings and fluorescent dye fills from dorsal pressure-sensitive (P) cells, the first neurons that could be reliably identified in the early embryo. We followed the development of the P cell from the first extension of neurites to the elaboration of an adult-like arbor. After the growth of primary neurites, we observed a profuse outgrowth of transient neurites within the neuropil. Retraction of the transient neurites left the primary branches studded with spurs. After a dormant period, stable secondary branches grew apparently from the spurs and became tipped with terminals. At this time, neurites of the Retzius (R) cell, a known presynaptic partner in the adult, were observed to apparently contact the terminals. Although voltage-dependent currents were seen in the P cell at the earliest stage, spontaneous synaptic activity was only observed when terminals had formed. Spontaneous release was observed before evoked release could be detected from the R cell. Our results suggest that transient neurites are formed during an exploratory phase of development, whereas the more precisely timed outgrowth of stable neurites from the spurs signals functional differentiation during synaptogenesis. Because spurs have also been observed in neurons of the mammalian brain, they may constitute a primordial synaptic organizer.

Expression of the c-kit proto-oncogene and its ligand stem cell factor (SCF) in normal and malignant human testicular tissue

Recent findings suggest an important role of the proto-oncogene c-kit, a surface membrane receptor of the tyrosine kinase family, and its ligand stem cell factor (SCF) in normal spermatogenesis and possibly in the pathogenesis of certain testicular germ cell tumors. To further investigate this potential role, the expression of c-kit and SCF was studied in normal and malignant human testicular tissue specimens at the mRNA and protein level by Northern blot analysis and immunohistochemistry, respectively. The detection of the c-kit receptor in normal human germ cells and its natural ligand SCF in Sertoli cells suggests the presence of a local trophic regulatory system that may be active in human spermatogenesis. Additionally, c-kit expression was detected in the seminoma but not in the nonseminoma subtype of human testicular germ cell tumors (GCT). Stem cell factor was not expressed at the mRNA level in tissue from either subtype of GCT as determined by Northern blot analysis; however, the protein was detected immunohistochemically in the cytoplasm of rare tumor cells.

Insulin-inducible changes in insulin receptor mRNA splice variants

Alternative splicing of insulin receptor pre-mRNA has been shown to be regulated in a tissue-specific and developmental manner. We investigated whether the receptor ligand might regulate the relative distribution of alternatively spliced mRNA in insulin-sensitive cells and found that changes in the relative expression of the two alternatively spliced insulin receptor RNA isotypes expressed in hepatocytes are regulated by insulin. In addition, we observed significant differences (p < or = 0.001) in insulin receptor isotype expression in subjects who were hyperinsulinemic and insulin-resistant versus subjects who were insulin-sensitive. These results support a role for insulin in the regulation of the relative expression of alternatively spliced mRNA expressed in insulin-responsive cells and tissues.

Pursuit eye movements in late-onset esotropia

Horizontal, smooth pursuit eye movements were recorded from adults and children with infantile and late-onset esotropia using a remote, video-based, eye-movement recording system. Each subject monocularly tracked a 0.5-degree target moving back and forth on a video monitor at a constant velocity of 10 degrees, over a range of 12 degrees. Each subject's nasal and temporal gain (eye velocity/target velocity) was measured. Confirming the results of previous studies, we found that infantile esotropes had asymmetrical pursuit eye movements (nasal gain greater than temporal gain) while late-onset esotropes had symmetrical gains. However, unlike previous investigators, we found that half of the late-onset esotropes had impaired pursuit gain. The magnitude of the pursuit abnormality and the amount of refractive error were correlated--patients with the highest refractive error had the lowest pursuit gain.