Health-related quality of life in rural cancer survivors compared with their urban counterparts: a systematic review.

PURPOSE: We conducted a systematic review to describe health-related quality of life (HRQOL) in rural cancer survivors (RCS), and compare HRQOL between RCS and urban cancer survivors (UCS). METHOD: We searched Medline, Embase, CINAHL Plus, and PsycINFO for studies with HRQOL in adult cancer survivors living in rural, regional, remote, and urban areas, who had completed definitive primary cancer treatment, without evidence of residual disease. Where available, we used normative and clinically important values to ascribe meaning to HRQOL data. FINDINGS: Fifteen studies (16 papers) were included. Most were from the US (n = 8) and reported on breast cancer survivors (n = 9). Six HRQOL instruments, collecting data across 16 domains, were used. Three instruments were specific to the survivorship phase. Normative and clinical data were available for 12 studies. Compared with normative populations, RCS had clinically worse physical HRQOL (6/12 studies), better social/family (5/7), and functional (3/6) HRQOL, and there were no differences in emotional or/mental HRQOL (9/12). In six studies with rural-urban comparator groups and normative and clinically important data, RCS and UCS had clinically worse physical (3/6 and 2/6, respectively) and better social/family (3/4 and 2/4 studies, respectively) HRQOL than normative populations. Functional HRQOL was better in RCS (2/4 studies) than UCS and normative populations. In 3/6 studies, there were no clinical differences in emotional or/mental HRQOL between RCS, UCS, and normative populations. CONCLUSION: Overall, HRQOL is not clearly better or worse in RCS than UCS. Future research should include different tumor types, rural residents, and survivorship-specific HRQOL instruments.

Priority recommendations for the implementation of patient-reported outcomes in clinical cancer care: a Delphi study.

PURPOSE: The aim of this study was to develop priority recommendations for the service level implementation of patient-reported outcomes (PROs) into clinical cancer care. METHODS: Development of draft guidance statements was informed by a literature review, the Knowledge to Action (KTA) implementation framework, and discussion with PRO experts and cancer survivors. A two-round modified Delphi survey with key stakeholders including cancer survivors, clinical and research experts, and Information Technology specialists was undertaken. Round 1 rated the importance of the statements and round 2 ranked statements in order of priority. RESULTS: Round 1 was completed by 70 participants with round 2 completed by 45 participants. Forty-seven statements were rated in round 2. In round 1, the highest agreement items (>90% agreement) included those that focused on the formation of strong stakeholder partnerships, ensuring ongoing communication within these partnerships, and the use of PROs for improvement and guidance in clinical care. Items ranked as the highest priorities in round 2 included assessment of current staff capabilities and service requirements, mapping of workflows and processes to enable collection, and using collected PROs to guide improved health outcomes. CONCLUSIONS: This stakeholder consultation process has identified key priorities in PRO implementation into clinical cancer care that include clinical relevance, stakeholder engagement, communication, and integration within the existing processes and capabilities. IMPLICATION FOR CANCER SURVIVORS: Routine adoption of PRO collection by clinical cancer services requires multiple implementation steps; of highest priority is strong engagement and communication with key stakeholders including cancer survivors.

Management of metastatic renal cell carcinoma in the era of targeted therapies.

BACKGROUND: Metastatic renal cell cancer is associated with poor prognosis and survival and is resistant to conventional chemotherapy. Therapeutic targeting of molecular pathways for tumour angiogenesis and other specific activation mechanisms offers improved tumour response and prolonged survival. AIMS: To conduct a retrospective audit of metastatic renal cell carcinoma patients treated with targeted therapies. METHODS: Data were extracted from clinical records of patients undergoing targeted treatment between 2005 and 2009 at two hospital sites. Data collected included pathology, systemic therapy class, toxicity and survival. Univariate and multivariate survival analyses were performed. RESULTS: Sixty-one patients were treated with 102 lines of therapy with a median overall survival (OS) of 23 months, median time to failure of first-line treatment (TTF1) of 10 months and median time to failure of second-line treatment (TTF2) of 5.2 months. Time from first diagnosis to treatment >12 months was significantly associated with improved OS, longer TTF1, TTF2 and response to first-line anti-vascular endothelial growth factor receptor tyrosine kinase inhibitors (anti-VEGF TKI) therapy. Variables associated with tumour biology, natural history and the systemic inflammatory response were associated with improved OS and TTF1. Development of hypertension was predictive of anti-VEGF TKI outcome. Toxicities were as expected for each drug class. CONCLUSIONS: Survival and toxicity outcomes from two Australian sites are comparable to published data. The adverse event profile differs to conventional chemotherapy. Clinicians caring for patients with metastatic renal cancer will need to become familiar with these toxicities and their management as these agents enter widespread use.

The diet quality of adult women participating in a behavioural weight-loss programme.

BACKGROUND: Diet quality plays an important role in health and has been shown to impact the risk of heart disease and certain cancers. The present study aimed to examine baseline and 16-week follow-up levels of energy intake, energy density and diet quality, as measured by the Healthy Eating Index 2005 (HEI-2005), in overweight and obese women participating in a behavioural weight-loss programme. METHODS: Sixty-six women [mean (SD) age 48.6 (10.8) years; body mass index 31.8 (3.7) kg m(-2) ; 92% Caucasian] completed dietary measures at baseline and follow-up. All participants received a 16-week Internet Behavioural weight-loss programme based on the core of the Diabetes Prevention Program. Dietary intake was measured using the 2005 Block food frequency questionnaire. Diet quality was calculated using the HEI-2005. Paired t-tests were used to determine changes over time. RESULTS: There was a reduction in reported energy intake [7.867 (3.232) MJ versus 5.748 (1.775) MJ, P < 0.001] over the 16 weeks. Participants had an increase in diet quality [HEI score = 53.9 (9.9) versus 57.4 (10.6), P = 0.002] as well as a reduction in energy density [0.0088 (0.0021) MJ g(-1) to 0.0080 (0.0021) MJ g(-1) (P = 0.002)]. All micronutrient intakes decreased over the 16 weeks. CONCLUSIONS: Participation in a 16-week behavioural weight-loss programme significantly improved diet quality and reduced dietary energy density and energy intake in adult women. However, despite the overall increase in diet quality score, there were deficiencies in key micronutrients in the diets of most women at the conclusion of the 16-week study.

Genetic associations of fatigue and other symptoms following breast cancer treatment: A prospective study.

BACKGROUND: Cancer-related fatigue, mood disturbances, pain and cognitive disturbance are common after adjuvant cancer therapy, but vary considerably between individuals despite common disease features and treatment exposures. A genetic basis for this variability was explored in a prospective cohort. METHODS: Physical and psychological health of women were assessed prospectively following therapy for early stage breast cancer with self-report questionnaires. Participation in a genetic association sub-study was offered. Indices for the key symptom domains of fatigue, pain, depression, anxiety, and neurocognitive difficulties were empirically derived by principal components analysis from end-treatment questionnaires, and then applied longitudinally. Genetic associations were sought with functional single nucleotide polymorphisms (SNPs) in pro- and anti-inflammatory cytokine genes - tumour necrosis factor (TNF)-α (-308 â€‹GG), interferon (IFN)-É£ (+874 â€‹TA), interleukin (IL)-10 (1082 â€‹GA and -592 CA), IL-6 (-174 â€‹GC), IL-1ß (-511 â€‹GA). RESULTS: Questionnaire data was available for 210 participants, of whom 111 participated in the genetic sub-study. As expected, symptom domain scores generally improved over several months following treatment completion. Tumour and adjuvant treatment related factors were unassociated with either severity or duration of the individual symptom domains, but severity of symptoms at end-treatment was strongly associated with duration for each domain (all p â€‹< â€‹0.05). In multivariable analyses, risk genotypes were independently associated with: fatigue with IL-6 -174 â€‹GG/GC and IL-10 -1082 GG; depression and anxiety with IL-10 -1082 AA; neurocognitive disturbance: TNF-α -308 GG; depression IL-1ß (all p â€‹< â€‹0.05). The identified SNPs also had cumulative effects in prolonging the time to recovery from the associated symptom domain. CONCLUSIONS: Genetic factors contribute to the severity and duration of common symptom domains after cancer therapy.

Real-world deployment of lateral flow SARS-CoV-2 antigen detection in the emergency department to provide rapid, accurate and safe diagnosis of COVID-19.

BACKGROUND: Point-of-care (POC) SARS-CoV-2 lateral-flow antigen detection (LFD) testing in the emergency department (ED) could inform rapid infection control decisions but requirements for safe deployment have not been fully defined. METHODS: Review of LFD test results, laboratory and POC-RT-PCR results and ED-performance metrics during a two-week high SARS-CoV-2 prevalence period followed by several months of falling prevalence. AIM: Determine whether LFD testing can be safely deployed in ED to provide an effective universal SARS-CoV-2 testing capability. FINDINGS: 93% (345/371) of COVID-19 patients left ED with a virological diagnosis during the 2-week universal LFD evaluation period compared to 77% with targeted POC-RT-PCR deployment alone, on background of approximately one-third having an NHS Track and Trace RT-PCR test-result at presentation. LFD sensitivity and specificity was 70.7% and 99.1% respectively providing a PPV of 97.7% and NPV of 86.4% with disease prevalence of 34.7%. ED discharge-delays (breaches) attributable to COVID-19 fell to 33/3532 (0.94%) compared with the preceding POC-RT-PCR period (107/4114 (2.6%); p=<0.0001). Importantly, LFD testing identified 1 or 2 clinically-unsuspected COVID-19 patients/day. Three clinically-confirmed LFD false positive patients were appropriately triaged based on LFD action-card flowchart, and only 5 of 95 false-negative LFD results were inappropriately admitted to non-COVID-19 areas where no onward-transmission was identified. LFD testing was restricted to asymptomatic patients when disease prevalence fell below 5% and detected 1-3 cases/week. CONCLUSION: Universal SARS-CoV-2 LFD testing can be safely and effectively deployed in ED alongside POC-RT-PCR testing during periods of high and low disease prevalence.

Domains in ferroelectric nanodots.

Almost free-standing single crystal mesoscale and nanoscale dots of ferroelectric BaTiO(3) have been made by direct focused ion beam patterning of bulk single crystal material. The domain structures which appear in these single crystal dots, after cooling through the Curie temperature, were observed to form into quadrants, with each quadrant consisting of fine 90 degrees stripe domains. The reason that these rather complex domain configurations form is uncertain, but we consider and discuss three possibilities for their genesis: first, that the quadrant features initially form to facilitate field-closure, but then develop 90 degrees shape compensating stripe domains in order to accommodate disclination stresses; second, that they are the result of the impingement of domain packets which nucleate at the sidewalls of the dots forming "Forsbergh" patterns (essentially the result of phase transition kinetics); and third, that 90 degrees domains form to conserve the shape of the nanodot as it is cooled through the Curie temperature but arrange into quadrant packets in order to minimize the energy associated with uncompensated surface charges (thus representing an equilibrium state). While the third model is the preferred one, we note that the second and third models are not mutually exclusive.

A survey of prelicensure pain curricula in health science faculties in Canadian universities.

OBJECTIVE: The present exploratory, descriptive study aimed to determine the designated time for mandatory pain content in curricula of major Canadian universities for students in health science and veterinary programs before being licensed. METHOD: Major Canadian university sites (n=10) were chosen where health science faculties included at least medicine (n=10) and nursing (n=10); many also included dentistry (n=8), pharmacy (n=7), physical therapy (n=8) and/or occupational therapy (n=6). These disciplines provide the largest number of students entering the workforce but are not the only ones contributing to the health professional team. Veterinary programs (n=4) were also surveyed as a comparison. The Pain Education Survey, developed from previous research and piloted, was used to determine total mandatory pain hours. RESULTS: The majority of health science programs (67.5%) were unable to specify designated hours for pain. Only 32.5% respondents could identify specific hours allotted for pain course content and/or additional clinical conferences. The average total time per discipline across all years varied from 13 h to 41 h (range 0 h to 109 h). All veterinary respondents identified mandatory designated pain content time (mean 87 h, range 27 h to 200 h). The proportion allotted to the eight content categories varied, but time was least for pain misbeliefs, assessment and monitoring/follow-up planning. CONCLUSIONS: Only one-third of the present sample could identify time designated for teaching mandatory pain content. Two-thirds reported 'integrated' content that was not quantifiable or able to be determined, which may suggest it is not a priority at that site. Many expressed a need for pain-related curriculum resources.

Evaluation of the age-dependent dosing recommendations for the administration of daily tinzaparin in children with thrombosis.

Essentials The once-daily dosing of tinzaparin provides an advantage over other low molecular weight heparins. The recommended age-dependent doses of tinzaparin in children have not previously been validated. Once-daily administration of tinzaparin is a safe and effective treatment of childhood thrombosis. Recommended doses are appropriate but monitoring may be required due to inter-individual variation. SUMMARY: Background The recommended starting doses of tinzaparin for the treatment of thrombosis in children have not previously been validated. There are few data to support the efficacy and safety of once-daily tinzaparin dosing in children with thrombosis. Objectives To investigate the use of tinzaparin for the treatment of childhood thrombosis, and to evaluate the age-dependent dosing recommendations and define outcomes in terms of efficacy and safety. Methods This was a retrospective cohort study of children aged 0 to < 16 years treated for thrombosis at a large teaching hospital in the UK between 2008 and 2015. Medical records were reviewed to evaluate tinzaparin dosing, anti-activated factor X (FXa) levels, and patient outcomes. Results Seventy-nine children were identified as having received tinzaparin. Dosing information was available for 57. Younger children required higher doses to reach a therapeutic level. The therapeutic dose requirement varied within age groups, supporting the use of anti-FXa monitoring. Over a median follow-up of 35 months, there were 13 (16%) bleeding episodes (two major; seven clinically relevant but non-major; and four minor). There were two (3%) recurrent episodes of thrombosis. Children were treated for a median duration of 3 months, and the majority (86%) remained on tinzaparin for the duration of their anticoagulant therapy. Conclusion Once-daily tinzaparin is a safe and effective treatment for childhood thrombosis, with rates of recurrence and bleeding similar to those for other anticoagulants used in children. The recommended starting doses are appropriate, but anti-FXa monitoring may be required, owing to interindividual variability in the therapeutic dose requirement.

Endothelin and dopamine release.

Endothelins and endothelin receptors are widespread in the brain. There is increasing evidence that endothelins play a role in brain mechanisms associated with behaviour and neuroendocrine regulation as well as cardiovascular control. We review the evidence for an interaction of endothelin with brain dopaminergic mechanisms. Our work has shown that particularly endothelin-1 and ET(B) receptors are present at significant levels in typical brain dopaminergic regions such as the striatum. Moreover, lesion studies showed that ET(B) receptors are present on dopaminergic neuronal terminals in striatum and studies with local administration of endothelins into the ventral striatum showed that activation of these receptors causes dopamine release, as measured both with in vivo voltammetry and behavioural methods. While several previous studies have focussed on the possible role of very high levels of endothelins in ischemic and pathological mechanisms in the brain, possibly mediated by ET(A) receptors, we propose that physiological levels of these peptides play an important role in normal brain function, at least partly by interacting with dopamine release through ET(B) receptors.

Rapid and specific uptake of anti-Tac disulfide-stabilized Fv by interleukin-2 receptor-bearing tumors.

The disulfide-stabilized Fv (dsFv) is a novel form of a variable-region fragment (Fv) of an antibody which is stabilized by an interchain disulfide bond. As a consequence, it is more stable than its Fv analogue. Anti-Tac(dsFv) is derived from anti-Tac(IgG) which specifically binds to the p55 subunit of the interleukin-2 receptor (IL2R alpha). The receptor is found in large numbers on activated T cells and many T-cell leukemias. The biodistribution patterns of 125I-anti-Tac(dsFv) and 125I-anti-Tac(IgG) were determined in athymic nude mice bearing two s.c. tumors, one expressing a stably transfected plasmid encoding IL2R alpha (ATAC4) and one composed of parental untransfected A431 epidermoid carcinoma cells. Anti-Tac(dsFv), which has a molecular weight of 25,000, was specifically captured by the ATAC4 tumors but not by control A431 tumors. The antigen-specific tumors accumulated > 2% of the injected dose/g within 15-45 min after i.v. injection. The level of radioactivity in the ATAC4 tumors was maintained at > 1% of the injected dose/g for nearly 6 h, at which time the ATAC4 tumors contained 11-fold more 125I-anti-Tac(dsFv) than did the A431 tumors. Unbound 125I-anti-Tac(dsFv) was rapidly cleared from the blood with apparently biphasic pharmacokinetics (alpha t 1/2 = < 10 min; beta t 1/2 = approximately 5.5 h). Initially, the bulk of the 125I-anti-Tac(dsFv) appeared in the kidneys. In contrast, 125I-anti-Tac(IgG) showed no tumor- or tissue-specific uptake over the 24-h time course of the experiments and remained primarily in the blood stream (blood clearance t 1/2 = approximately 12 h). This is the first report of the biodistribution of a dsFv fragment. Because of its rapid uptake by IL2 receptor-bearing tumors, short serum half-life, and increased stability, radiolabeled anti-Tac(dsFv) may be useful for the imaging and therapy of neoplasias expressing the IL2 receptor.

B3(Fab)-PE38M: a recombinant immunotoxin in which a mutant form of Pseudomonas exotoxin is fused to the Fab fragment of monoclonal antibody B3.

Recombinant immunotoxins were made by fusing the Fab domain of monoclonal antibody (MAb) B3 to PE38M, a truncated mutant form of Pseudomonas exotoxin (PE). The recombinant toxins were made in Escherichia coli by fusing genes encoding the antibody domains to a gene encoding the mutant form of PE. MAb B3 binds to a carbohydrate antigen found on many kinds of carcinomas. Immunotoxins in which MAb B3 has been chemically coupled to recombinant forms of PE have been shown to be very active cytotoxic agents. PE has also been targeted to tumor cells by replacing the cell-binding domain of PE (domain I) with a single-chain antibody to make a single-chain immunotoxin. In the current study, PE38M, a mutant form of PE, with a deletion of the cell-binding domain (amino acids 1-252) as well as mutations in domain III and some nonessential sequences in domain Ib (amino acids 365-380), was fused to the light chain of MAb B3. This protein was renatured in the presence of the Fd fragment of MAb B3 to produce a Fab-toxin fusion protein. Alternatively, the Fd fragment of MAb B3 was fused to PE38M and combined with the light chain. Both types of B3(Fab)-PE38M were just as active on target cells as previously described single-chain immunotoxins. Furthermore, the B3(Fab)-PE38M produced complete remissions of human tumor xenografts growing in nude mice. B3(Fab)-PE38M has two advantages over single-chain immunotoxins. One is that the yield of recombinant Fab-toxin is very high, with 10-22% of the starting protein recovered as cytotoxically active immunotoxin after chromatographic purification. The second is that the B3(Fab)-PE38M has a much longer survival in the circulation of mice with a t1/2 beta of approximately 5 h.

Biodistribution of 18F- and 125I-labeled anti-Tac disulfide-stabilized Fv fragments in nude mice with interleukin 2 alpha receptor-positive tumor xenografts.

We evaluated the biodistribution, pharmacokinetics, and generation of catabolites of an 18F- and 125I-labeled anti-Tac disulfide-stabilized Fv fragment (dsFv) in tumor-bearing nude mice. This dsFv is genetically engineered from a murine monoclonal antibody that recognizes the alpha subunit of the interleukin 2 (IL-2 alpha) receptor. Labeling was performed with 18F using N-succinimidyl 4-([18F]fluoromethyl)benzoate or with 125I using the Iodo-Gen method. The immunoreactivities of the radiolabeled anti-Tac dsFv were > 82%. The biodistribution was evaluated (at 15, 45, and 90 min and 6 h) in athymic nude mice (approximately five/group) bearing s.c. tumor xenografts. Cell line A431 served as the IL-2 receptor-negative control tumor, whereas the ATAC4 cell line served as our IL-2 receptor-positive tumor. Animals received injections of 18F-labeled anti-Tac dsFv (0.7-1.4 megabecquerels/1.5-3 micrograms) and 125I-labeled anti-Tac dsFv (0.1-0.4 megabecquerels/0.9-1 microgram). Blood clearance for both preparations was rapid, with < 10% retained in the blood by 15 min. Maximum accumulation in ATAC4 tumors occurred between 45 and 90 min and peaked at a mean of 4.2% injected dose/g (18F) and 5.6% of injected dose/g (125I). At 6 h, the ATAC4 tumors contained 11 times more 18F and 3 times more 125I than did the A431 tumors. The ATAC4 tumor:blood ratios for the 18F and 125I were > 12:1 and > 1.4:1 at 6 h, respectively, whereas the ratios for the antigen-negative A431 tumor were less than 1. The kidneys were the major route of elimination. Catabolites appeared quickly and were identified as [125I]iodide and predominantly N-epsilon-[18F]4-fluoromethylbenzoyl(alpha-N-acetyl) lysine. This is the first study to evaluate the biodistribution of an 18F-labeled Fv fragment in vitro and in vivo. In vivo, the dsFv was taken up rapidly by the kidneys, producing lysine-containing catabolites for 18F-labeled dsFv and [125I]iodide for 125I-labeled dsFv.

L-lysine effectively blocks renal uptake of 125I- or 99mTc-labeled anti-Tac disulfide-stabilized Fv fragment.

In this study, we investigated the ability of L-lysine to block renal uptake of 125I- or 99mTc- labeled Fv fragments. Anti-Tac disulfide-stabilized Fv fragment (dsFv) was derived from a murine monoclonal antibody that recognizes the alpha subunit of the interleukin-2 receptor (IL-2R alpha). The 125I- or 99mTc-labeled dsFv was injected i.v. into non-tumor-bearing nude mice or into nude mice bearing SP2/Tac (IL-2R alpha positive) and SP2/0 (IL-2R alpha negative) tumor. We then evaluated the pharmacokinetics of L-[3H]lysine and the effect of L-lysine dose, timing of administration, and route of delivery on catabolism and biodistribution of i.v. dsFv. Peak renal uptake of i.v. or i.p. injected L-[3H]lysine occurred within 5 and 15 min, respectively. The kidney uptake of L-lysine exhibited a dose-response effect. When L-lysine was coinfused or injected shortly before dsFv, renal uptake of dsFv was blocked to < 5% of the control, but longer intervals were less effective. Aminosyn II and Travasol 10% (parenteral amino acid solutions) also blocked renal uptake of radiolabeled dsFv. Administration of L-lysine did not alter the blood kinetics and slightly increased the tumor uptake of dsFv, but it did prevent catabolism in the kidney and resulted in lower amounts of catabolites in the serum and urine. In conclusion, we have shown that a blocking dose of lysine, injected with or immediately before the injection of radiolabeled dsFv, is most effective in blocking the renal uptake of dsFv. This is consistent with the rapid uptake of L-[3H]lysine by the kidney and is further substantiated by the relative ineffectiveness of lysine injected immediately after the radiolabeled dsFv injection.

Improved biodistribution of 125I-labeled anti-Tac disulfide-stabilized Fv fragment by blocking its binding to the alpha subunit of the interleukin 2 receptor in the circulation with preinjected humanized anti-Tac IgG.

Animal studies using radiolabeled anti-Tac disulfide-stabilized Fv (dsFv) monoclonal antibody have shown formation of complexes in serum with the soluble alpha subunit of the interleukin 2 receptor alpha (sIL-2R alpha). In this study, we improved the targeting of 125I-labeled anti-Tac dsFv to receptor-positive tumors in the presence of circulating receptor by preinjecting unlabeled humanized anti-Tac IgG antibody (HuTac IgG). We used mice bearing SP2/Tac tumor xenografts that express the IL-2R alpha. A positive correlation was seen between tumor size and the concentration of circulating receptor. Tumor-bearing mice were injected with 125I-labeled anti-Tac dsFv (400 ng), either alone or 15 min after injection of HuTac IgG. The 125I-labeled anti-Tac dsFv formed high molecular weight complexes with the sIL-2R alpha. The fraction of the dsFv present in the complexes increased as tumor size increased (greater sIL-2R alpha levels). The fractions of dsFv in the complexes were 9.9- to 11.6-fold higher when sIL-2R alpha was not blocked with preinjected HuTac IgG. The administration of a 12-fold molar excess of HuTac IgG over sIL-2R alpha resulted in >80% of the 125I activity present as the dsFv rather than in the complexes. Furthermore, the biodistribution of 125I-labeled anti-Tac dsFv was improved by blocking its binding to sIL-2R alpha by preinjecting HuTac IgG. Specifically, in the preinjected group, at 15 min postinjection, the 125I-labeled anti-Tac dsFv levels in tumor increased to 10.8% compared to 5.6% injected dose per gram in the non-preinjected group. In summary, our studies showed that preinjection of HuTac IgG can block the formation of complexes of circulating sIL-2R alpha and 125I-labeled anti-Tac dsFv. This blockade is associated with faster blood clearance, higher tumor uptake, and greater tumor:nontumor ratios of the radiolabeled antibody fragment.

The regulation of biologic products derived from bioengineered plants.

Recently, there has been a large increase in the number and types of biological products--from therapeutic antibodies to vaccines for the prevention of infectious diseases--that are produced in bioengineered plant systems. We anticipate that this technology will be used increasingly on a commercial scale for the manufacture of human and animal products. These production systems have the capacity to produce very large quantities of products at lower costs and with reduced risks compared with mammalian systems.

Cytotoxic and antitumor activity of a recombinant tumor necrosis factor-B1(Fv) fusion protein on LeY antigen-expressing human cancer cells.

We have constructed a fusion protein composed of tumor necrosis factor alpha (TNF-alpha) fused at its COOH terminus to the scFv region of monoclonal antibody (mAb) B1, an antibody that recognizes LeY antigen present on many human cancer cells. Our rationale for fusing the scFv to the COOH terminus of TNF was to diminish the binding of the fusion protein to TNF receptors because the COOH terminus of TNF is involved in binding, and thus to partially inactivate (detoxify) the molecule. The Fv region should then target and accumulate the fusion protein on cancer cells, which should compensate for the reduced binding affinity of the TNF moiety and lead to selective killing of TNF-sensitive antigen-expressing cancer cells. The fusion protein was expressed in Escherichia coli and found in insoluble inclusion bodies. After refolding and purification by anion exchange, Ni-NTA affinity, and size-exclusion chromatography, we obtained monomeric TNF-B1(Fv). This molecule binds to LeY antigen on cancer cells with the same affinity as B1(scFv) and B1(scFv) immunotoxins but with significantly lower affinity to the TNF receptor compared to the TNF trimer. TNF-B1(Fv) is very toxic to LeY antigen-expressing cancer cells that are sensitive to TNF (e.g., MCF-7 breast or CRL-1739 gastric cancer cells). This cytotoxicity is antibody targeted and TNF mediated because it can be prevented (as shown on MCF-7 cells) by an antibody competing for LeY antigen binding and by an antibody that neutralizes TNF-alpha. TNF-B1(Fv) kills TNF-alpha-sensitive cells that do not express the target antigen only at much higher doses than TNF trimer, and it does not kill LeY-bearing but TNF-alpha-resistant cells. TNF-B1(Fv) can cause significant tumor regression of MCF-7 tumor xenografts in mice at doses that are not toxic to the mice. Thus, the reduced binding of the TNF moiety to TNF receptors, combined with binding of the B1(Fv) portion to LeY antigen, makes TNF-B1(Fv) an agent for selective killing of LeY-expressing TNF-sensitive cancer cells.

Imaging and phase I study of 111In- and 90Y-labeled anti-LewisY monoclonal antibody B3.

B3 is a murine monoclonal antibody (mAb) that recognizes a LewisY carbohydrate antigen present on the surface of many carcinomas. An imaging and Phase I trial was performed to study the ability of 111In-mAb B3 to image known metastasis and determine the maximum tolerated dose (MTD), dose-limiting toxicity (DLT), kinetics, and biodistribution of 90Y-mAb B3. Patients (n = 26) with advanced epithelial tumors that express the LewisY antigen were entered. All patients received 5 mCi of 111In-mAb B3 for imaging. 90Y-mAb B3 doses were escalated from 5 to 25 mCi in 5-mCi increments. 111In-mAb B3 and 90Y-mAb B3 were coadministered over a 1-h infusion. Definite tumor imaging was observed in 20 of 26 patients. Sites imaged included lung, liver, bone, and soft tissues. The MTD of 90Y-mAb B3 was determined to be 20 mCi. The DLTs were neutropenia and thrombocytopenia. Tumor doses ranged from 7.7 to 65.1 rad/mCi. 111In- and 90Y-mAb B3 serum pharmacokinetics (n = 23) were found to be similar. The amount of B3 administered (5, 10, and 50 mg) did not alter the pharmacokinetics. Bone marrow biopsies (n = 23) showed 0.0038+/-0.0016% of injected dose/gram for 111In-mAb B3 compared to 0.0046+/-0.0017% of injected dose/gram for 90Y-mAb B3 (P = 0.009). When given to patients with carcinomas that express the LewisY antigen, 111In-mAb B3 demonstrated good tumor localization. The MTD of 90Y-mAb B3 is 20 mCi, with myelosuppression as the DLT. Higher doses of radioactivity need to be delivered to achieve an antitumor effect. Humanized mAb B3 is being developed for evaluation in radioimmunotherapy. A clinical trial to explore the use of higher doses of 90Y-mAb B3 with autologous stem cell support is planned.

Preparation and characterization of a disulfide-stabilized Fv fragment of the anti-Tac antibody: comparison with its single-chain analog.

Recombinant DNA techniques now allow the production of "mini-antibodies" called Fv fragments. These have been produced either as the independent variable domains of the heavy and light chains non-covalently associated in one-to-one stoichiometry or as single-chain gene products with the two domains linked by an intervening peptide sequence. Although Fv fragments can have excellent binding properties, they are often difficult to produce in good yield and lack the characteristic stability of whole antibodies. To improve the stability of the Fv molecule, we have introduced a cysteine residue into conserved framework regions of both the heavy and light variable domains from the anti-Tac antibody at positions compatible with the formation of an interdomain disulfide linkage (i.e. VH-44 and VL-99). The mutant subunits form a disulfide-bonded Fv molecule, which binds to the alpha-subunit of the IL2 receptor (IL2R alpha) with an affinity identical to that of humanized anti-Tac IgG. This disulfide-stabilized Fv (dsFv) proved to be substantially more resistant to denaturation by heat or urea treatment than the single-chain Fv (scFv). Furthermore, the yield of dsFv is -four-fold higher than that of the single-chain analog.

Mitotic and gender parallels in Alzheimer disease: therapeutic opportunities.

In this review, we discuss the role of cell cycle dysfunction in the pathogenesis of Alzheimer disease and propose that such mitotic catastrophe, as one of the earliest events in neuronal degeneration, may, in fact, be sufficient to initiate the neurodegenerative cascade. The question as to what molecule initiates cell cycle dysfunction is now beginning to become understood and, in this regard, the gender-predication, age-related penetrance and regional susceptibility of specific neuronal populations led us to consider luteinizing hormone as a key mediator of the abnormal mitotic process. As such, agents targeted toward luteinizing hormone or downstream sequelae may be of great therapeutic value in the treatment of Alzheimer disease.