The plant pathogen enzyme AldC is a long-chain aliphatic aldehyde dehydrogenase.

Aldehyde dehydrogenases are versatile enzymes that serve a range of biochemical functions. Although traditionally considered metabolic housekeeping enzymes because of their ability to detoxify reactive aldehydes, like those generated from lipid peroxidation damage, the contributions of these enzymes to other biological processes are widespread. For example, the plant pathogen Pseudomonas syringae strain PtoDC3000 uses an indole-3-acetaldehyde dehydrogenase to synthesize the phytohormone indole-3-acetic acid to elude host responses. Here we investigate the biochemical function of AldC from PtoDC3000. Analysis of the substrate profile of AldC suggests that this enzyme functions as a long-chain aliphatic aldehyde dehydrogenase. The 2.5 Å resolution X-ray crystal of the AldC C291A mutant in a dead-end complex with octanal and NAD+ reveals an apolar binding site primed for aliphatic aldehyde substrate recognition. Functional characterization of site-directed mutants targeting the substrate- and NAD(H)-binding sites identifies key residues in the active site for ligand interactions, including those in the "aromatic box" that define the aldehyde-binding site. Overall, this study provides molecular insight for understanding the evolution of the prokaryotic aldehyde dehydrogenase superfamily and their diversity of function.

Native Mass Spectrometry Analysis of Oligomerization States of Fluorescence Recovery Protein and Orange Carotenoid Protein: Two Proteins Involved in the Cyanobacterial Photoprotection Cycle.

The orange carotenoid protein (OCP) and fluorescence recovery protein (FRP) are present in many cyanobacteria and regulate an essential photoprotection cycle in an antagonistic manner as a function of light intensity. We characterized the oligomerization states of OCP and FRP by using native mass spectrometry, a technique that has the capability of studying native proteins under a wide range of protein concentrations and molecular masses. We found that dimeric FRP is the predominant state at protein concentrations ranging from 3 to 180 µM and that higher-order oligomers gradually form at protein concentrations above this range. The OCP, however, demonstrates significantly different oligomerization behavior. Monomeric OCP (mOCP) dominates at low protein concentrations, with an observable population of dimeric OCP (dOCP). The ratio of dOCP to mOCP, however, increases proportionally with protein concentration. Higher-order OCP oligomers form at protein concentrations beyond 10 µM. Additionally, native mass spectrometry coupled with ion mobility allowed us to measure protein collisional cross sections and interrogate the unfolding of different FRP and OCP oligomers. We found that monomeric FRP exhibits a one-stage unfolding process, which could be correlated with its C-terminal bent crystal structure. The structural domain compositions of FRP and OCP are compared and discussed.

Effectiveness of a Survivorship Program: An Assessment of Patients With Breast Cancer in a Community Setting.

PURPOSE: This study assesses the effectiveness of a single institution's breast cancer survivorship program on patient perceptions, quality of life (QOL), and compliance with National Comprehensive Cancer Network (NCCN) guidelines for follow-up. METHODS: Sampled patients completed all their breast cancer treatment at a single tertiary center. Surveys designed to evaluate QOL were obtained, and retrospective medical record review was conducted to assess NCCN compliance. Survivorship clinic (SC) attendees and nonattendees were matched for age and disease stage for comparison of the outcomes (QOL, NCCN compliance, and overall effectiveness). RESULTS: SC patients (n = 63) tended to perceive their concerns in various categories to be addressed more adequately than did nonattendees (n = 54), with significant differences in the areas of practical concerns (P = .03) and late-term adverse effects (P = .03). There was a significant difference in compliance with three NCCN guidelines (history and physical every 3 to 6 months, annual mammography, and a pelvic examination if on tamoxifen) between survivorship attendees and nonattendees (P < .001, P = .02, and P < .001, respectively). Women who attended an SC used other survivorship support resources more often. CONCLUSION: Survivorship programs can be time and resource consuming, but our study is one of the first to show that a survivorship program effectively changes patient behavior in important ways. Patients who attended an SC were more likely to be compliant with NCCN-recommended follow-up and to use other survivorship resources and felt their concerns were better addressed. These measures can be used to help us improve our survivorship services and by other institutions to measure the quality and effectiveness of their programs.

Yttrium 90-ibritumomab tiuxetan plus rituximab maintenance as initial therapy for patients with high-tumor-burden follicular lymphoma: a Wisconsin Oncology Network study.

INTRODUCTION: Yttrium 90-ibritumomab tiuxetan (90Y-IT) radioimmunotherapy has proved to be effective in relapsed follicular lymphoma (FL). We conducted a clinical trial in which 90Y-IT followed by maintenance rituximab (MR) was evaluated as initial therapy for high-tumor-burden FL. METHODS: Eligible patients had histologically confirmed FL and met the GELF (Groupe d'Etude des Lymphomes Folliculaires) criteria for high tumor burden. All patients received a single dose of 90Y-IT. Patients with platelet counts of 150,000/mm³ or higher received 0.4 mCi/kg, and patients with platelet counts between 100,000/mm³ and 149,000/mm³ received 0.3 mCi/kg. At 6 months, patients without progressive disease (PD) received rituximab weekly for 4 weeks at a dose of 375 mg/m² (consolidation therapy), followed by MR consisting of the same dose every 3 months for a planned 5 years. RESULTS: From January 2005 through November 2007, a total of 16 patients were enrolled. The median age was 52 years (range, 37-75). The major toxicity from 90Y-IT was myelosuppression, with 88% and 31% of the patients experiencing grade 3 and grade 4 hematologic toxicity, respectively. The responses to 90Y-IT induction therapy were as follows: 7 patients with complete response/unconfirmed complete response (CR/Cru), 4 with partial response (PR), 3 with stable disease (SD), and 2 with progressive disease (PD). We identified 6 patients with early PD (range, 4-16 months) and 10 patients with prolonged remission (range, 37-101+ months). Compared with the patients who had prolonged remission, the patients who had early PD tended to have larger baseline nodal masses. The median progression-free survival (PFS) has not been reached after a median follow-up period of 48 months. The 3-year PFS and overall survival (OS) rates were 56% (95% CI, 37%-87%) and 93% (95% CI, 80%-100%), respectively. CONCLUSION: The overall response rate (ORR) to 90Y-IT was 69% in patients who had previously untreated, high-tumor-burden FL, which is lower than what is observed with contemporary rituximab/chemotherapy combinations. MR after 90Y-IT did convert all PRs to CRs. Alternative therapies should be considered for patients who have FL with large nodal masses (>9 cm), whereas very durable responses are possible in patients who have intermediate-size masses (>9 cm).

An exploratory study of the use of advance directives by US oncologists.

PURPOSE: This study sought to determine the rate of advance directive completion among US oncologists and factors influencing such a decision. METHODS: We surveyed 7590 members of the American Society of Clinical Oncology using a web-based questionnaire. RESULTS: The response rate was 8.1%. Most respondents (59%) had completed at least 1 document: 9% living will, 9% power of attorney for health care, and 41% both. Respondents who were older, men, married, with children, working in the community setting, radiation oncologists, and practicing general oncology were more likely than their counterparts to have an advance directive. Among those who had one, 95% and 36% had discussed their wishes with their loved ones and health care providers, respectively. Factors including experience at work, spouse, children, family, and religion had the most influence on respondents' decision. The majority of those without an advance directive reported either no reason or lack of time. Those who had them were more likely to report having a comprehensive review of their wishes with those closest to them, being more knowledgeable, having more routine discussions with their patients, and being more comfortable helping their patients complete one. CONCLUSION: Only about half of US oncologists who responded to our survey have completed an advance directive.

Clinical trial accrual among new cancer patients at a community-based cancer center.

BACKGROUND: To the authors' knowledge, only limited data are available regarding clinical trial accrual patterns and the barriers encountered among newly diagnosed patients seen at community-based cancer centers. METHODS: In the current study, the authors prospectively collected clinical and sociodemographic data from all adult patients seen at a community-based cancer center who had new cancers diagnosed between 2003-2004. Clinical trial enrollment decisions were noted and factors that prevented accrual were identified. RESULTS: There was a total of 1012 new cancer patients. In 587 patients (58%), clinical trials appropriate for the diagnosis and stage of disease were not available. Among those patients for whom trials were available, 19.8% did not meet eligibility criteria, and only 9.9% of patients were enrolled. Although more trials were found to be available for women compared with men (51% vs. 32%; P < 0.01), the accrual rates were equal (11.2% vs. 7.6%; P = 0.24). Elderly patients comprised approximately 59.4% of those patients with available trials, but they were less likely to be enrolled (5.1% vs. 16.8%; P < 0.01). The major barriers to nonparticipation can be grouped into protocol limitations (68.1%), physician triage (16%), and patient decisions (15.9%). The overall accrual rate when all patients were included was 4% (42 of 1012 patients). CONCLUSIONS: At the study institution, participation in clinical trials is reported to be low. The unavailability of appropriate clinical trials represents the most significant barrier. Continuing efforts to encourage physicians and to educate patients remain necessary. If the current study findings are found to be applicable to other community-based cancer centers, making a larger variety of clinical trials available to the community may help to improve the accrual of patients to national cancer clinical trials.