Time-to-progression in breast cancer: a stratification model for clinical trials

The development of new anti-tumour drugs without clear cytoreductive activity has necessitated changes in the design of clinical trials. Defining the "time" parameter has become the essential objective of the majority of these trials. However, in breast cancer, this parameter is highly variable and, as such, difficult to quantify. We developed a useful tool that takes into account the inter-relatedness of all the variables known to have the capacity to predict the time-to-progression (TTP) in advanced breast cancer. From the Alamo database (GEICAM), we selected 1798 patients diagnosed as having metastatic breast cancer. Univariate analysis was performed using the method of Kaplan-Meier. Multivariate analysis was with the Cox regression method. The variables that were shown to have independent predictive value for the TTP were: non-visceral metastatic disease, single metastases, hormonal receptor positive N/T ratio<2 and disease-free interval (DFI) > or = 24 months. Taking into account the variables that had reached an independent predictive value, we constructed a model of scoring in which the patients were grouped according to the TTP. Using our new scoring model, it is possible to group patients with metastatic breast cancer according to the predicted TTP. This can be a useful tool at the time of selecting and stratifying patients on entry into new randomised clinical trials.     

Urinary excretion of low molecular weight proteins in patients with pure monoclonal light chain proteinuria

BACKGROUND: Because urinary low molecular weight protein (LMWP) measurement shows changes in renal integrity at an early stage, beta2-microglobulin (B2m), retinol-binding protein (RBP) and alpha1-microglobulin (A1m) were evaluated in 24-hour urine collection of 65 patients with pure monoclonal light chain (MLC) proteinuria and in 47 patients with different kidney diseases (DKDs) for comparison.METHODS AND RESULTS: Albumin, kappa, lambda, A1m and B2m were measured by immunonephelometry. RBP was determined by ELISA. The mean values of LMWP quantitation were significant for origin of the disease (MLC and DKD) (p<0.05) and renal failure (RF) (p<0.001) (MANOVA). Tukey HSD test only showed significant differences for LMWP between MLC patients with RF and DKD patients without RF. The mean value of A1m was different between patients with and without RF in each group (p<0.05 for MLC, and p<0.01 for DKD). In the group without RF, the frequency of A1m excretion above 12 mg/L differed between MLC patients and DKD patients (p<0.01). CONCLUSION: A tubular dysfunction occurred in a great number of patients excreting pure MLC even in those with well-preserved renal function, as it did in patients with DKDs. In patients with MLC without RF, A1m might be measured for the early recognition of tubular involvement.     

Over-expression of neuropathy target esterase activity in bovine chromaffin cell cultures by adenovirus-mediated gene transfer

Chromaffin cells in culture show high neuropathy target esterase (NTE) activity. It is well known that inhibition and specific modification of NTE by some organophosphorus (OPs) compounds induces a neurodegenerative neuropathy. It has been suggested that NTE is responsible for phosphatidylcholine homeostasis, although its role in neuropathy induction remains unclear. The cDNA of human NTE (4.4kbp) was inserted into an adenoviral vector. Bovine chromaffin cells cultured at 50,000 cells/well were incubated with the vector for 2h and after removing the volume of infection, cells were maintained in the incubator. After 24h, NTE activity was 6.8+/-0.5mU/10(6) cells in untreated cells and 14.8+/-1.5mU/10(6) cells, 19.3+/-2.9mU/10(6) cells, 24.8+/-0.9mU/10(6) cells and 30.9+/-1.0mU/10(6) cells in cells incubated with 2, 4, 8 and 16microl of vector, respectively. After 60min of inhibition with mipafox increased concentrations, the calculated I(50) (60min) values were 5.5, 6.2 and 6.6microM for cells infected with 0, 2 and 10microl of vector preparation. We confirm that the adenoviral vector containing the human NTE gene is active in bovine chromaffin cells in culture and that the NTE activity expressed by the vector shows the same inhibition pattern by the neuropathic OP mipafox as the NTE activity of bovine chromaffin cells and cells remained viable after the high NTE activity expression.     

Evidence-based use of taxanes in the adjuvant setting of breast cancer. A review of randomized phase III trials

Six major randomized clinical trials evaluating the role of taxanes in the adjuvant setting of breast cancer have demonstrated significant improvements in terms of efficacy in favour of the taxane treatment arm. In all cases, different anthracycline-based regimens were used as the control arm. Nevertheless, many clinicians are still not sufficiently convinced to incorporate the routine use of taxanes in the adjuvant treatment of breast cancer. There are two main objections, first the possible lack of effectiveness of chemotherapy in hormone-receptor positive tumors and second, some of the anthracycline-based control arms used in these trials were not the optimal ones. In this review, we have searched and analyzed all randomized studies that evaluated the role of taxanes in the adjuvant setting of breast cancer patients and have reported results in terms of efficacy or tolerance. The suitability of the control arm, the prospective definition of patient's subgroups and the statistical methodology were taking into account. The objective of this review was to analyze if, at this point in time, there is sufficient evidence to support the routine use of taxanes in the adjuvant setting of breast cancer, and if it is valid for all subgroups including hormone-receptor and Her2/neu positive breast cancer patients. Other objectives of this review were to define the optimal regimen for administration of taxanes, how the tolerability of taxanes may be improved and also, to investigate any potential differences in efficacy or tolerability between docetaxel and paclitaxel.     

Exploring the short-term impact of DNA-testing in breast cancer patients: the counselees' perception matters, but the actual BRCA1/2 result does not

Objective

Previous studies suggest that learning a DNA-test-result has no direct impact on the medical-decisions and psychological well-being of counselees. Their perception, especially their recollections and interpretations of their cancer-risks and heredity, predict and/or mediate this impact. These studies were criticized for their small range of predictors, mediators, outcomes and contextual factors. We studied the short-term impact of DNA-testing with an extended model.

Methods

Three months after disclosure of BRCA1/2-test-results, we sent counselees a questionnaire about their perception, medical and psychological outcomes, and medical, familial and psychological contexts. 248 affected women participated; 30 had received pathogenic-mutations, 16 unclassified-variants and 202 uninformative-results.

Results

The actually communicated genetic-information and the contextual variables predicted the counselees’ perception, but did not directly predict any outcomes. The counselees’ perception predicted and/or completely mediated the counselees’ medical intentions and behavior, physical and psychological life-changes, stigma, mastery, negativity and cancer-worries. Short-term distress was related to the perception not only of their own risks, but also of their relatives’ risks and heredity-likelihood. Effect sizes were medium to large.

Conclusions and implications

The outcomes of DNA-testing were better predicted by the counselees’ perception than by the actually given genetic-information. We recommend genetic-counselors to have tailored, interactive dialogues about the counselees’ perception.     

Mutations in PLOD2 cause autosomal-recessive connective tissue disorders within the Bruck syndrome-Osteogenesis imperfecta phenotypic spectrum

PLOD2 and FKBP10 are genes mutated in Bruck syndrome (BS), a condition resembling osteogenesis imperfecta (OI), but that is also typically associated with congenital joint contractures. Herein, we sought mutations in six consanguineous BS families and detected changes in either PLOD2 or FKBP10 in all cases. Two probands were found with a homozygous frameshift mutation in the alternative exon 13a of PLOD2, indicating that specific inactivation of the longer protein isoform encoded by this gene is sufficient to cause BS. In addition, by homozygosity mapping, followed by a candidate gene approach, we identified a homozygous donor splice site mutation in PLOD2 in a patient with autosomal‐recessive OI (AR‐OI). Screening of additional samples also revealed compound heterozygous mutations in PLOD2 in two brothers, one affected with mild AR‐OI and the other with mild BS. Thus, PLOD2 in addition to causing BS is also associated with AR‐OI phenotypes of variable severity. Hum Mutat 33:1444–1449, 2012. © 2012 Wiley Periodicals, Inc.     

Molecular analysis of mucopolysaccharidosis IVA (Morquio A) in Spain

Mucopolysaccharidosis type IVA (Morquio A) is an inherited metabolic disease with autosomal recessive inheritance. The pathology is due to a deficient activity of N-acetylgalactosamine-6-sulfate-sulfatase, which is involved in the degradation of keratan sulfate and chondroitin-6-sulfate. To date more than 150 mutations have been described in the GALNS gene in different populations. The aim of this study was to analyze the mutations and polymorphisms in Spain in order to know the epidemiology of our population and also to offer genetic counseling to affected families. We found 30 mutant alleles in the 15 families analyzed completing all the genotypes. Most of the mutations that we found were missense mutations, six of which were novel: p.S74F, p.E121D, p.Y254C, p.E260K, p.T394P and p.N495Y; we also found a small deletion (c.1142delC) and a probable deep intronic mutation that causes the loss of exon 5 (c.423_566del) found in cDNA. Both mutations are described in this study for the first time. We also identified 20 polymorphisms previously reported and 2 novel ones: (c.633+222T/C and c.898+25C>G). In conclusion, we have identified the mutations responsible for Mucopolysaccharidosis IV A in Spain. We found great allelic heterogeneity, as occurs in other populations, which hinders the establishment of genotype-phenotype correlations in Spain. This study has been very useful for genetic counseling to the affected families.     

Deletions of the RUNX2 gene are present in about 10% of individuals with cleidocranial dysplasia

Cleidocranial Dysplasia (CCD) is an autosomal dominant skeletal disorder characterized by hypoplastic or absent clavicles, increased head circumference, large fontanels, dental anomalies, and short stature. Hand malformations are also common. Mutations in RUNX2 cause CCD, but are not identified in all CCD patients. In this study we screened 135 unrelated patients with the clinical diagnosis of CCD for RUNX2 mutations by sequencing analysis and demonstrated 82 mutations 48 of which were novel. By quantitative PCR we screened the remaining 53 unrelated patients for copy number variations in the RUNX2 gene. Heterozygous deletions of different size were identified in 13 patients, and a duplication of the exons 1 to 4 of the RUNX2 gene in one patient. Thus, heterozygous deletions or duplications affecting the RUNX2 gene may be present in about 10% of all patients with a clinical diagnosis of CCD which corresponds to 26% of individuals with normal results on sequencing analysis. We therefore suggest that screening for intragenic deletions and duplications by qPCR or MLPA should be considered for patients with CCD phenotype in whom DNA sequencing does not reveal a causative RUNX2 mutation. © 2010 Wiley‐Liss, Inc.