High level analysis of genomic data reveals complex predictors of response to trastuzumab (T) and chemotherapy for early stage breast cancer

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Background: Trastuzumab (T) with chemotherapy has been shown to improve survival in breast cancer patients but de novo resistance is common. Identifying predictors of response to T in primary cancers may lead to an understanding of mechanisms of resistance. We investigated whether combined microarray datasets from patients with early breast cancer treated with preoperative T and chemotherapy could predict for response to therapy. Methods: Two cohorts of patients with HER2 3+/FISH+, stage II-III breast cancer were included in this analysis: trial 1- T and docetaxel (n=38), trial 2 -T and vinorelbine (n=48), both for 12 weeks. Frozen tissue core biopsies were available and successfully amplified in 41 patients (trial 1: 20, trial 2: 21 patients), with standard sample processing, RNA extraction, amplification and hybridization to Affymetrix U133 chips. Differential expression of genes and chromosomal regions, (defined as >10 genes in a given chromosomal cytoband), between patients with pathologic complete response (pCR) vs. those with residual invasive disease were examined. A measure of total functional aneuploidy (tFA) was calculated by summing net deviation in expression of all chromosomal regions and a gene expression signature of genomic instability (CIN) was derived by the identification of genes showing a high level of correlation with tFA . Results: By unsupervised hierarchical analysis, both datasets interdigitated suggesting no inherent bias. Gene expression patterns of individual genes showed weak associations with pCR. However, distinct statistically significant chromosomal regions, Chr2p23 Chr6q24 Chr7q33 Chr2p2 Chr12q21.31 Chr14q32.2 Chr1p34.2 Chr8q21.3, were associated with pCR to T therapy (p<0.005), and were confirmed in more than 50% samples by SNP analysis. In addition, resistant tumors showed higher levels of the CIN signature (p<0.005). Conclusions: We have shown that gene expression data can be merged and used for discovery predictive chromosomal regions associated T response. In addition, chromosomal instability was associated with T resistance. If validated, these distinct dysregulated chromosomal regions may serve as predictive markers of response to trastuzumab therapy.

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Results of phase I clinical trials of Coramsine in patients with advanced solid tumors

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Background: Coramsine (C) is a 1:1 mixture of solasonine and solamargine, plant glycoalkaloids found in the species Solanum Linneanum, with single agent and synergistic combination in vitro and in vivo preclinical efficacy in various tumor models through interaction with rhamnose-containing cell membrane glycoproteins and subsequent internalization. Methods: C initially as a 2-hr IV infusion daily × 5 every 2 weeks to define the MTD, recommended Phase II dose, toxicity and pharmacokinetics. Based on preclinical toxicology the infusion duration was increased to 4 hours and 24 hours (120 hr continuous infusion). Doses studied range from 0.75 mg/kg/day to 3.0 mg/kg/day. Results: 27 pts were treated. DLT occurred in 2/2 pts at 1.5 mg/kg/day (2 hr) and 2/2 pts each at 3.0 mg/kg/day (4 hr and 24 hr). Preceding dose levels 1.0 mg/kg (2 hr) and 1.5 mg/kg (4 hr) produced DLT in 2/6 pts each with no grade IV. Over 24 hr, 2.25 mg/kg/day produced DLT in 4/6 patients. Limiting toxicity at all schedules was grade III/IV transaminitis with grade I-III increases of bilirubin and grade I-II creatinine. Hepatotoxicity was maximal at days 3–5, resolved over 10–21 days, was clinically asymptomatic apart from grade I-II fatigue, and was not cumulative. No myelosuppression or other serious drug-related toxicity was recorded. Partial responses were documented in 2 pts (renal, NSCLC) and minor response in 1 pt with unknown primary. Responses were seen using both 2 hr and 4 hr infusions. Pharmacokinetic parameters for solasonine and solamargine are linear across the narrow range of doses studied with elimination T1/2 of 5.57 ± 1.27 hr (solasonine), 8.40 ± 2.00 hr (solamargine) and Cl of 5.6 ± 1.6 L/hr (solasonine), 3.0 ± 0.7 L/hr (solamargine). Peak levels of both exceed active in vitro levels (>2,000 ng/ml). Conclusions: Coramsine produces dose-limiting hepatotoxicity at doses above 1.0 mg/kg/day over 2 hours or 1.5 mg/kg/day over 4 hours. 2.25 mg/kg/day over 24 hours exceeds the MTD. Activity has been seen against resistant solid tumors. Phase II studies in renal cancer and melanoma will be performed using 1.5 mg/kg/day over 4 hours.

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Case report:DNA testing resolves unusual results in the Dombrock system

Typing for antigens in the Dombrock blood group system and identifying the corresponding antibodies are notoriously difficult tasks. The reagents are scarce and the antibodies are weakly reactive. When RBCs from family members of a patient with an antibody to a high-prevalence Dombrock antigen were tested for compatibility,an unusual pattern of inheritance was observed:RBCs from the patient's children and one niece, in addition to those from some of the patient's siblings,were compatible. This prompted the performance of DNA-based assays for DO alleles and the results obtained were consistent with and explained the compatibility test results. It was possible to study this large kindred because of the cooperation of family members, hospital personnel, and reference laboratory staff.

An evaluation of the change in activity and workload arising from diabetic ophthalmology referrals following the introduction of a community based digital retinal photographic screening programme

AIMS

To determine how the workload of an ophthalmology department changed following the introduction of an organised retinal screening programme.

METHODS

Information was collected from the hospital medical record of people with diabetes attending eye clinics over 4 years. The first year was before screening, the next 2 years the first round, and the fourth year the second round.

RESULTS

The total number of people with diabetes referred each year over the 4 year period was 853, 954, 974, 1051 consecutively. The number of people with diabetes in the county rose by 1400 per annum. The total number of referrals for an opinion about diabetic retinopathy was 227, 333, 363, 368, for cataract was 64, 57, 77, 93, and for glaucoma was 57, 62, 61, 68. The total number of patients referred for laser treatment over the 4 years was 77, 124, 111, and 63

CONCLUSION

This study suggests that the workload in the eye clinic increases in the first round of screening but in subsequent rounds it does not fall below the pre-screening level, except for laser treatment. This may be partly because of increasing numbers of people with diabetes. With the introduction of a national screening programme, this has significant workload implications for the National Health Service.

Serosurvey for canine distemper virus exposure in dogs in communal lands in Zimbabwe

Sera from 173 apparently healthy, unvaccinated dogs from 4 widely separated communal lands in Zimbabwe were tested by ELISA for antibodies against canine distemper virus. Overall, 82% were positive with high prevalences found in each communal land. The highest seroprevalence was in dogs between 1 and 2 years of age (91%; 49/54). These results show dogs in the communal lands of Zimbabwe are commonly exposed to canine distemper virus and that a substantial number survive infection. The role that the virus might play in the high mortality rate of the dog population on communal land warrants further investigation.

Economic analysis of unrelated allogeneic bone marrow transplantation: results from the randomized clinical trial of T-cell depletion vs unmanipulated grafts for the prevention of graft-versus-host disease

Unrelated-donor marrow transplantation is a potential option for transplant candidates lacking a compatible related donor. The T-cell Depletion Study compared the 3-year disease-free survival for patients receiving T-cell-depleted (TCD) donor marrow (n = 203) vs unmanipulated donor marrow with methotrexate and cyclosporine (M/C) (n = 207). Hospital costs during index admission were documented with billing data, while hospital costs during subsequent 6-month follow-up were estimated from case report forms. Patients with index admission billing were included in the analysis (TCD = 119, M/C = 127). Total hospital length of stay (LOS) was similar across groups, with medians 47.0 days for TCD and 52.0 days for M/C (P = 0.72). Total hospital costs were comparable, 145,115 dollars vs 141,981 dollars (P = 0.63) for TCD and M/C, respectively. However, controlling for site and patient characteristics, TCD was associated with a 12.1% reduction in LOS for the index admission (95% CI -19.4%, -4.3%). Independent of treatment, HLA matching (6/6) was associated with an 8.6% (95% CI -17.4%, +1.2%) reduction in the index admission LOS, while cost was lower by 15.8% (95% CI -26.7%, -3.3%). Treatment costs were similar for TCD and M/C study groups. Savings on reduced cost for treating acute graft-versus-host disease were likely offset by increase in serious infections in the TCD arm.

Met receptor dynamics and signalling

The receptor for hepatocyte growth factor (HGF), Met, controls a programme of invasive growth that combines proliferation with various moto- and morphogenetic processes. This process is important for development and organ regeneration, but dysregulation in transformed tissues can contribute to cancer progression and metastasis. Acute stimulation of tissue culture cells with HGF leads to Met downregulation via degradation through an endocytic mechanism that also requires proteasome activity. Perturbation of Met trafficking on the endocytic pathway, either at the level of the internalisation step or during sorting at the early endosome, leads to altered signalling outputs. Ubiquitination of Met through the E3-ligase Cbl is required for receptor downregulation, and a mutant receptor defective in Cbl binding is able to transform cells. We discuss the hypothesis that some naturally occurring Met mutants implicated in cancer may transform cells owing to defects in their trafficking along the endosomal degradation pathway.

Polymorphisms of the equine major histocompatibility complex class II DRA locus

The full extent of the polymorphism of ELA-DRA in Equidae is not yet known. Given the apparent differences in DRA polymorphisms between Equidae and other species, the aims of this study were to more fully characterize ELA-DRA, determine the extent of gene polymorphism and establish the allele-frequency distribution. An allele reference panel for the second exon of ELA-DRA was established by sequence-based typing of 69 equine DNA samples consisting of various breeds of domestic horse (Equus caballus), together with donkeys (Equus asinus), Grant's zebras (Equus boehmi) and one onager (Equus hemionus). Five of the six previously reported alleles detected using single-strand conformation polymorphism were found: ELA-DRA*0101, ELA-DRA*0201, ELA-DRA*0301, ELA-DRA*0501 (Albright-Fraser DG et al. Polymorphism of DRA among equids. Immunogenetics 1996: 43: 315-7) and ELA-DRA*0601 (GenBank accession number AF5419361). In addition to the previously reported alleles, five novel ELA-DRA alleles were detected within the ELA-DRA allele reference panel. One of these was identified in E. caballus (ELA-DRA*JBH11), one in E. boehmi and E. hemionus (ELA-DRA*JBZ185) and three in E. asinus (ELA-DRA*JBD3, ELA-DRA*JBD17 and ELA-DRA*JBH45). A total of 565 equine DNA samples were screened using reference-strand-mediated conformation analysis, a double-stranded conformation-based mutation detection system that can be used to type existing ELA-DRA alleles and identify new variants. Based on our findings, at least 11 ELA-DRA alleles are now known to exist, and this level of polymorphism at the DRA locus appears to be unique to the genus Equus. Both the previously reported alleles and the new alleles displayed a species-specific distribution.

Experimental and theoretical study of the infrared spectra of BrHI− and BrDI−

Gas phase vibrational spectra of BrHI- and BrDI- have been measured from 6 to 17 microm (590-1666 cm(-1)) using tunable infrared radiation from the free electron laser for infrared experiments in order to characterize the strong hydrogen bond in these species. BrHI-.Ar and BrDI-.Ar complexes were produced and mass selected, and the depletion of their signal due to vibrational predissociation was monitored as a function of photon energy. Additionally, BrHI- and BrDI- were dissociated into HBr (DBr) and I- via resonant infrared multiphoton dissociation. The spectra show numerous transitions, which had not been observed by previous matrix studies. New ab initio calculations of the potential-energy surface and the dipole moment are presented and are used in variational ro-vibrational calculations to assign the spectral features. These calculations highlight the importance of basis set in the simulation of heavy atoms such as iodine. Further, they demonstrate extensive mode mixing between the bend and the H-atom stretch modes in BrHI- and BrDI- due to Fermi resonances. These interactions result in major deviations from simple harmonic estimates of the vibrational energies. As a result of this new analysis, previous matrix-isolation spectra assignments are reevaluated.

Rovibrational energy levels of hydrogen peroxide, studied by MULTIMODE with a reaction path Hamiltonian

Recently, Carter and Handy [J. Chem. Phys. 113 (2000) 987] have introduced the theory of the reaction path Hamiltonian (RPH) [J. Chem. Phys. 72 (1980) 99] into the variational scheme MULTIMODE, for the calculation of the J=0 vibrational levels of polyatomic molecules, which have a single large-amplitude motion. In this theory the reaction path coordinate s becomes the fourth dimension of the moment-of-inertia tensor, and must be treated separately from the remaining 3N-7 normal coordinates in the MULTIMODE program. In the modified program, complete integration is performed over s, and the M-mode MULTIMODE coupling approximation for the evaluation of the matrix elements applies only to the 3N-7 normal coordinates. In this paper the new algorithm is extended to the calculation of rotational-vibration energy levels (i.e. J>0) with the RPH, following from our analogous implementation for rigid molecules [Theoret. Chem. Acc. 100 (1998) 191]. The full theory is given, and all extra terms have been included to give the exact kinetic energy operator. In order to validate the new code, we report studies on hydrogen peroxide (H2O2), where the reaction path is equivalent to torsional motion. H2O2 has previously been studied variationally using a valence coordinate Hamiltonian; complete agreement for calculated rovibrational levels is obtained between the previous results and those from the new code, using the identical potential surface. MULTIMODE is now able to calculate rovibrational levels for polyatomic molecules which have one large-amplitude motion.

Multidisciplinary team working, clinical networks, and chambers; opportunities to work differently in the NHS

Recently in the United Kingdom some new organisational structures for clinicians have been discussed. So far little has changed, but the intensity of interest suggests this may be an opportunity to link change in working practices with improvements in quality. Multidisciplinary team working is developing within the National Health Service (NHS) and some groups are expanding their roles across traditional institutional boundaries to form complex clinical networks. It would require little to make these functional networks autonomous from current NHS structures. Other models of working without traditional institutional boundaries have been discussed, including the formation of "chambers" for doctors and other professionals. We describe the first tentative steps of one group as an example and suggest that further experimentation with evaluation is required.

A mobile-bearing total knee prosthesis compared with a fixed-bearing prosthesis. A multicentre single-blind randomised controlled trial

Before proceeding to longer-term studies, we have studied the early clinical results of a new mobile-bearing total knee prosthesis in comparison with an established fixed-bearing device. Patients requiring bilateral knee replacement consented to have their operations under one anaesthetic using one of each prosthesis. They also agreed to accept the random choice of knee (right or left) and to remain ignorant as to which side had which implant. Outcomes were measured using the American Knee Society Score (AKSS), the Oxford Knee Score (OKS), and determination of the range of movement and pain scores before and at one year after operation. Preoperatively, there was no systematic difference between the right and left knees. One patient died in the perioperative period and one mobile-bearing prosthesis required early revision for dislocation of the meniscal component. At one year the mean AKSS, OKS and pain scores for the new device were slightly better (p < 0.025) than those for the fixed-bearing device. There was no difference in the range of movement. We believe that this is the first controlled, blinded trial to compare early function of a new knee prosthesis with that of a standard implant. It demonstrates a small but significant clinical advantage for the mobile-bearing design.

Circulating levels of inhibin A, activin A and follistatin in missed and recurrent miscarriages

BACKGROUND

The aim of this study was to investigate the changes in circulating levels and the clinical use of inhibin A, activin A and follistatin as endocrine markers of early pregnancy loss.

METHODS

Blood samples were collected from women presenting with a sporadic missed miscarriage (n = 10), and controls having pregnancy termination at 8-12 weeks (n = 15) and from women with a history of unexplained recurrent miscarriages (n = 12) at 6-12 weeks gestation. All samples were assayed for inhibin A, inhibin B, activin A, follistatin, hCG, estradiol and progesterone.

RESULTS

Serum inhibin A, hCG, estradiol and progesterone levels were significantly ( approximately 2-3 fold) decreased in sporadic miscarriages compared with controls. In the recurrent miscarriage group, time dependent changes in plasma inhibin A and hCG levels were significantly (P < 0.05) altered in the group that had a subsequent miscarriage compared with those who had a live birth. At 6-7 weeks gestation, plasma inhibin A ( approximately 4 fold, P < 0.01), hCG ( approximately 4 fold, P < 0.01) and estradiol ( approximately 2 fold, P < 0.001) levels were significantly lower in women who went on to have another miscarriage than those with a live birth. Inhibin B levels were near the detection limit of the assay.

CONCLUSIONS

Our findings suggest that inhibin A is a specific marker of early pregnancy loss before the onset of the clinical symptoms of recurrent miscarriage. There is a high degree of association between levels of inhibin A and hCG in cases of miscarriage, indicating that these two proteins could be used in combination to predict future pregnancy outcome.

Injuries in Australian cricket at first class level 1995/1996 to 2000/2001

OBJECTIVE

To describe and analyse injuries and illness occurring in Australian cricket at first class level.

METHODS

Injuries occurring to the state and national teams were surveyed prospectively between the seasons 1998/1999 and 2000/2001, and the three preceding seasons were surveyed retrospectively. The definition of an injury was detailed and generally required the player to miss playing time in a major match.

RESULTS

Average injury match incidence in the seasons studied prospectively varied from a low of 19.0 injuries per 10 000 player hours in first class domestic matches to a high of 38.5 injuries per 10 000 player hours in one day internationals. The average seasonal incidence was 19.2 injuries per squad (25 players) per season (20 matches). Injury prevalence (the percentage of players missing through injury at any given time) was 14% for pace bowlers, 4% for spin bowlers, 4% for batsmen, and 2% for wicket keepers. The most common injuries were hamstring strains, side strains, groin injuries, wrist and hand injuries, and lumbar soft tissue injuries. Bowlers who had bowled more than 20 match overs in the week leading up to a match had an increased risk of sustaining a bowling injury (risk ratio 1.91, 95% confidence interval (CI) 1.28 to 2.85). A further risk for bowling injury is bowling second in a match-that is, batting first (risk ratio 1.62, 95% CI 1.04 to 2.50). A risk factor for injury in fielding is colliding with the boundary fence.

CONCLUSIONS

Further study is required to determine ways to minimise the risk of injury in fast bowlers. Cricket grounds should mark a boundary line on the playing field to prevent players colliding with fences in the field.