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Objetivo: Los inhibidores de la aromatasa (IA) se han asociado con una pérdida de masa ósea acelerada y un mayor riesgo de fracturas osteoporóticas. Con este trabajo se pretendió evaluar los factores de riesgo de fractura incidente en pacientes con cáncer de mama que reciben IA. Material y métodos: Estudio prospectivo-observacional de cohorte de mujeres con cáncer de mama que inician tratamiento con IA (cohorte B-ABLE). Las pacientes realizaron tratamiento durante 5 años o bien 2 ó 3 años si habían recibido previamente tamoxifeno. Se les evaluó la salud ósea desde el inicio del tratamiento hasta un año después de finalizar dicho tratamiento mediante densitometría ósea, marcadores de remodelado óseo, niveles de vitamina D y una radiografía antero-posterior y otra lateral de columna. Se realizó el cálculo de riesgo de fractura mediante la herramienta FRAX® antes de iniciar IA. Se utilizaron modelos de Cox para calcular los ratios de riesgo (HR [IC 95%]) de fractura. Resultados: Un total de 943 pacientes fueron incluidas en el estudio. El 5,4% sufrieron una fractura incidente, la mayoría durante el tratamiento con IA, aunque un 21,5% ocurrieron durante el primer año después de finalizar la terapia. La mayoría de las fracturas incidentes fueron vertebrales clínicas (29,4%) y de Colles (31,4%). El 86,3% de las pacientes tenían un diagnóstico de osteopenia u osteoporosis en el momento de la fractura y el 33% tenían los niveles de β-CTX (isómero β del telopéptido carboxiterminal del colágeno tipo I) por encima de la normalidad. Las pacientes diagnosticadas de osteoporosis o con riesgo de fractura al inicio del estudio fueron tratadas con antirresortivos óseos. No se encontraron diferencias significativas en el riesgo de fractura entre pacientes con y sin tratamiento antirresortivo: HR=1,75 [IC 95%: 0,88 a 3,46]. Tampoco se encontraron diferencias entre las pacientes que habían hecho tratamiento previo con tamoxifeno respecto a las que no (HR=1,00 [IC 95%: 0,39 a 2,56]). La herramienta FRAX® dio valores de media dentro del rango de riesgo intermedio, con 13 pacientes con valores de alto riesgo de fractura principal. Conclusiones: El principal factor de riesgo detectado para fractura incidente en pacientes tratadas con IA es el diagnóstico de osteopenia u osteoporosis. El cálculo de la herramienta FRAX® y la determinación de los niveles de β-CTX son herramientas útiles para identificar a pacientes de alto riesgo. [ABSTRACT FROM AUTHOR]

Objetive: Aromatase inhibitors (AI) have been associated with an accelerated loss of bone mass and an increased risk of osteoporosis fractures. This study assesses the risk factors for incident fracture in breast cancer patients receiving AI. Material and methods: Prospective-observational cohort study of women with breast cancer who begin treatment with AI (B-ABLE cohort). Patients were treated for 5 years or 2 or 3 years if they had previously received tamoxifen. Bone health was assessed from the beginning of the treatment until one year post treatment by bone densitometry, bone remodeling markers, vitamin D levels and an anteroposterior and lateral spine radiography. The fracture risk calculation was performed using the FRAX® tool before starting AI. Cox models were used to calculate the risk ratios (HR [95% CI]) of fracture. Results: A total of 943 patients were included in the study. 5.4% suffered an incident fracture, most during AI treatment, although 21.5% occurred during the first year after the end of therapy. Most of the incident fractures were clinical vertebral (29.4%) and Colles (31.4%). 86.3% of the patients had a diagnosis of osteopenia or osteoporosis at the time of the fracture and 33% had the levels of β-CTX (β isomer of the carboxyterminal telopeptide of type I collagen) above normal. Patients diagnosed with osteoporosis or at risk of fracture at the start of the study were treated with bone antiresorptives. No significant differences in fracture risk were found between patients with and without antiresorptive therapy: HR=1.75 [95% CI: 0.88 to 3.46]. Nor were differences found among patients who had previously treated with tamoxifen compared to those who did not (HR=1.00 [95% CI 0.39 to 2.56]). The FRAX® tool gave average values within the intermediate risk range, with 13 patients with high risk of major fracture values. Conclusions: The main risk factor detected for incident fracture in patients treated with AI is the diagnosis of osteopenia or osteoporosis. The calculation of the FRAX® tool and the determination of β-CTX levels are useful tools to identify high-risk patients. [ABSTRACT FROM AUTHOR]

Objectives: To identify microRNAs (miRNAs) differentially expressed in bone samples with osteoporotic fracture compared with healthy bones. Methods: Total RNA was extracted from fresh trabecular bone of the femoral neck of women undergoing hip replacement surgery, either because to osteoporotic fracture (n=6) or in the absence of osteoarthritis osteoporosis (based on BMD) (n=6). The samples were hybridized on an array of miRNAs and PCA diagrams and heat map were made. To compare expression levels, >1.5 times and a value p<0.05 Student's T test (corrected for multiple testing) was set as a threshold of significant change. Results: Both PCA analysis and the heat map showed a samples grouping whether there was fracture or not. 790 were detected miRNAs in bone samples, 82 of which were altered in the osteoporotic samples. After validation in another panel of 6 samples 6 osteoporotic and non-osteoporotic by PCR real time of the most significant miRNAs, and for which there was a test available, the miRNAs, miR-320a and miR-22-3p were confirmed. These two miRNAs were detected in cultures of primary osteoblasts, although they did not maintain the same pattern of expression in total bone samples. Conclusions: We have shown that there are differences in the expression of miRNAs in samples with osteoporotic fracture. This opens prospects for research and design of new therapies. [ABSTRACT FROM AUTHOR]

Aromatase inhibitors (AIs) used as adjuvant therapy in postmenopausal women with hormone receptor-positive breast cancer cause diverse musculoskeletal side effects that include bone loss and its associated fracture. About half of the 391 patients treated with AIs in the Barcelona–Aromatase induced bone loss in early breast cancer cohort suffered a significant bone loss at lumbar spine (LS) and/or femoral neck (FN) after 2 years on AI-treatment. In contrast, up to one-third (19.6% LS, 38.6% FN) showed no decline or even increased bone density. The present study aimed to determine the genetic basis for this variability. SNPs in candidate genes involved in vitamin D and estrogen hormone-response pathways (CYP11A1, CYP17A1, HSD3B2, HSD17B3, CYP19A1, CYP2C19, CYP2C9, ESR1, DHCR7, GC, CYP2R1, CYP27B1, VDR and CYP24A1) were genotyped for association analysis with AI-related bone loss (AIBL). After multiple testing correction, 3 tag-SNPs (rs4077581, s11632698 and rs900798) located in the CYP11A1 gene were significantly associated (P!0.005) with FN AIBL at 2 years of treatment. Next, CYP11A1 expression in human fresh bone tissue and primary osteoblasts was demonstrated by RT-PCR. Both common isoforms of human cholesterol side-chain cleavage enzyme (encoded by CYP11A1 gene) were detected in osteoblasts by western blot. In conclusion, the genetic association of CYP11A1 gene with AIBL and its expression in bone tissue reveals a potential local function of this enzyme in bone metabolism regulation, offering a new vision of the steroidogenic ability of this tissue and new understanding of AI-induced bone loss. [ABSTRACT FROM AUTHOR]

Objectives: The RANK/RANKL/OPG system is involved in the determination of bone mineral density (BMD) and bone microarchitecture. Our study seeks to evaluate if there are SNPs in the 3'UTR region of the RANK gene associated with osteoporotic phenotypes. Material and methods: Seven genetic variants in 1,098 women from the BARCOS cohort were genotyped, and their association with BMD and osteoporotic fractures evaluated. An interaction with SNP rs9594738 in the RANKL gene which was previously associated with BMD was tested. Results: None of the SNPs were associated significantly with BMD. SNP rs78326403 was associated with wrist/forearm fractures (Log-additive model odds ratio (OR)=3.12 [IC 95%: 1.69 ; 5.75]; p=7.16x10-4), while SNP rs884205 was associated with fractures of the spinal column (OR=4.05 Recessive; [95% CI: 1.59 ; 10.35]; p=8.24x10-3). Lastly, an interaction was detected between SNP rs9594738 from RANKL and rs78326403 from RANK on the presence of fracture (p=0.039). The analysis of the effects of combined genotypes rs9594738 and rs78326403 pointed to an increase in the prevalence of fractures in subjects with a greater number of unfavourable alleles, the ORs being 2.76 [95% CI: 1.30 ; 5.81]; p=0.007) and 5.14 [95% CI: 1.37 ; 15.67]; p=0.007) for 2 and ≥3 unfavourable alleles respectively, in comparison with none/1. Conclusions: Two SNPs in 3'UTR from the RANK gene predispose to site-dependent osteoporotic fracture. An interaction with SNP rs9594738 from RANKL suggests an additive effect of BMD and bone strength. [ABSTRACT FROM AUTHOR]

Objectives: The RANK/RANKL/OPG system is involved in the determination of bone mineral density (BMD) and bone microarchitecture. Our study seeks to evaluate if there are SNPs in the 3'UTR region of the RANK gene associated with osteoporotic phenotypes. Material and methods: Seven genetic variants in 1,098 women from the BARCOS cohort were genotyped, and their association with BMD and osteoporotic fractures evaluated. An interaction with SNP rs9594738 in the RANKL gene which was previously associated with BMD was tested. Results: None of the SNPs were associated significantly with BMD. SNP rs78326403 was associated with wrist/forearm fractures (Log-additive model odds ratio (OR)=3.12 [IC 95%: 1.69 ; 5.75]; p=7.16x10-4), while SNP rs884205 was associated with fractures of the spinal column (OR=4.05 Recessive; [95% CI: 1.59 ; 10.35]; p=8.24x10-3). Lastly, an interaction was detected between SNP rs9594738 from RANKL and rs78326403 from RANK on the presence of fracture (p=0.039). The analysis of the effects of combined genotypes rs9594738 and rs78326403 pointed to an increase in the prevalence of fractures in subjects with a greater number of unfavourable alleles, the ORs being 2.76 [95% CI: 1.30 ; 5.81]; p=0.007) and 5.14 [95% CI: 1.37 ; 15.67]; p=0.007) for 2 and ≥3 unfavourable alleles respectively, in comparison with none/1. Conclusions: Two SNPs in 3'UTR from the RANK gene predispose to site-dependent osteoporotic fracture. An interaction with SNP rs9594738 from RANKL suggests an additive effect of BMD and bone strength. [ABSTRACT FROM AUTHOR]

Polycaprolactone scaffolds modified with cross-linked hyaluronic acid were prepared in order to establish whether a more hydrophilic and biomimetic microenvironment benefits the progenitor cells arriving from bone marrow in a cell-free tissue-engineering approach. The polycaprolactone and polycaprolactone/hyaluronic acid scaffolds were characterized in terms of morphology and water absorption capacity. The polycaprolactone and polycaprolactone/hyaluronic acid samples were implanted in a chondral defect in rabbits; bleeding of the subchondral bone was provoked to generate a spontaneous healing response. Repair at 1, 4, 12, and 24 weeks was assessed macroscopically using the International Cartilage Repair Society score and the Oswestry Arthroscopy Score and microscopically using immunohistological staining for collagen type I and type II, and for Ki-67. The presence of hyaluronic acid improves scaffold performance, which supports a good repair response without biomaterial pre-seeding. [ABSTRACT FROM AUTHOR]

Background: The mechanisms behind ART-induced bone changes in HIV-infected patients are poorly known. We aimed to analyse changes in inflammatory and bone markers in HIV after tenofovir disoproxil fumarate initiation, and the associations with changes in the bone strength parameters.Methods: HIV-positive participants starting tenofovir disoproxil fumarate-based ART underwent dual-energy X-ray absorptiometry (QDR 4500 SL®, Hologic, Waltham, MA, USA) for bone mineral density (BMD), a microindentation test (OsteoProbe®, Active Life Scientific, Santa Barbara, CA, USA) for bone quality [bone material strength index (BMSi)] and phlebotomy at baseline and 48 weeks after ART. A panel of inflammatory biomarkers and bone turnover markers were measured by ELISA. HIV-negative controls underwent identical procedures once. Values are expressed as medians and IQRs, and non-parametric tests were used to perform the analysis.Results: Twenty HIV-infected individuals and 20 HIV-negative control individuals were matched in terms of age and gender. HIV individuals showed higher levels of inflammatory markers. We found no differences in bone turnover markers. HIV-positive individuals presented lower BMSi values at baseline compared with controls [86 (83-90) versus 89 (88-93), respectively; P = 0.034]. We found no difference in BMD (at either of the sites evaluated). BMSi tended to increase with treatment. IL-1β at baseline was positively correlated with changes in BMSi after ART (rho = 0.564, P = 0.014). Baseline levels of sclerostin tended to be negatively correlated with changes in BMSi (rho = -0.402, P = 0.097). We found a negative correlation between time since HIV diagnosis and changes in BMSi (rho = -0.466, P = 0.04).Conclusions: We observed a correlation between changes in bone quality and the inflammatory environment in HIV-positive individuals. Moreover, among the underlying mechanisms we highlight the Wnt pathway as having a potentially significant role in ART bone quality recovery. [ABSTRACT FROM AUTHOR]

Objectives: Aromatase inhibitors (AI) are effective adjuvant endocrine therapies for breast cancer patients, although they have been associated with an increased risk of osteoporotic fracture. Trabecular Bone Score (TBS) loss has been previously demonstrated, although it may vary among AI-treated patients. This study aims to identify the genetic basis associated with TBS change by studying steroidogenic pathway genes. Material and methods: The B-ABLE cohort studies prospectively postmenopausal women with breast cancer under treatment with AI. TBS is calculated from the raw data acquired in dual-energy x-ray absorptiometry (DXA) scan at the outset of the study and at the end of AI-treatment. The relative TBS change was calculated as the percentage variation of the TBS value at the end of treatment from baseline. To study the possible genetic association, nucleotide polymorphisms (SNPs) were genotyped in genes CYP11A1, CYP17A1, HDE3B2, HDE17B3, CYP19A1, CYP2C19, CYP2C9, ESR1, GC, CYP27B1, VDR and CYP24A1. The possible relationship between genes and TBS changes was studied by multiple linear regression, considering models of dominant, recessive and additive genetic inheritance. Results: The study included 212 women that had not been treated with bisphosphonates and had available TBS data. Half of the patients had been treated previously with tamoxifen. The percentage of intraindividual TBS change was -0.04% [95% CI: -0.05 to -0.03; p<0.001] at the end of AI treatment. The SNP rs6013897 in the gene CYP24A1 showed a significant association with TBS reduction [p=0.03565; coefficient ß (95% CI) = -1.55 (-2.98 to -0.11)]. Conclusions: The CYP24A1 gene could be involved in the phenotypic variability found in bone microarchitecture deterioration during AI treatment. [ABSTRACT FROM AUTHOR]

Summary: Camurati-Engelmann (CE) is a very rare disease affecting one in every million persons worldwide. It is characterized by an enlargement of long bones. We aimed to assess bone characteristics in three siblings with different tools. Even if there was an excess of bone density, quality seemed to be deteriorated. Introduction: CE disease is a rare monogenic disorder affecting approximately one in every million persons worldwide. It is mainly characterized by a progressive hyperostosis of the periosteum and endosteum of the diaphysis of long bones. Limited data are available about bone characteristics in these patients. In three siblings with CE disease, we aimed to assess bone mineral density (BMD) and trabecular bone score (TBS) by dual-energy X-ray absorptiometry (DXA) and material characteristics at tissue level using bone impact reference point indentation. Methods: Clinical data were collected and a general laboratory workup was performed. At the lumbar spine and hip, BMD and TBS were measured using DXA imaging. Bone material strength index (BMSi) was measured by bone impact microindentation using an Osteoprobe instrument. Results: All three cases had densitometric values consistent with high bone mass (sum of Z-score at the lumbar spine and hip > 4). Hip BMD was extremely high in all three siblings at both total hip and femoral neck, while at the lumbar spine, two of them had normal values but the third again had very high BMD. TBS values were in the normal range. In contrast, BMSi measurements were at low or very low levels, compared with normal controls. Conclusion: Despite strikingly increased BMD and normal microarchitecture, BMSi is affected in patients with CE. Microindentation could be an appropriate tool for assessing bone fragility in these patients. Bone disease in this group of patients requires further study to better understand the underlying regulatory mechanisms and their alterations. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to analyze bone mineral density (BMD) changes throughout aromatase inhibitor (AI) treatment in clinical cases and also consider its association with the CYP11A1 gene and the BMD variation after treatment. Material and methods: The B-ABLE cohort is a prospective study of postmenopausal women with breast cancer, in AI treatment. BMD variation was analyzed during AI treatment, as well as the differences those patients who were treated and not treated previously with tamoxifen (TMX). Three polymorphisms (rs4077581, rs11632698 and rs900798) of the CYP11A1 gene were genotyped for their association with BMD variation. Results: TMX-treated patients presented more rapid BMD loss than those who did not undergo prior TMX treatment (60% less in spine and 46% in femur at 2 years and 70% less in the spine and 63% in the femur at 3 years). However, no significant BMD loss was detected after treatment in either group. The 3 CYP11A1 gene polymorphisms were significantly associated with BMD variation in the femur at the end of the treatment. Conclusions: BMD was reduced more rapidly in patients with prior TMX treatment than in those who only received AI, although no significant differences were detected after treatment. The 3 CYP11A1 gene polymorphisms were associated with BMD variation in response to AI treatment. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to analyze bone mineral density (BMD) changes throughout aromatase inhibitor (AI) treatment in clinical cases and also consider its association with the CYP11A1 gene and the BMD variation after treatment. Material and methods: The B-ABLE cohort is a prospective study of postmenopausal women with breast cancer, in AI treatment. BMD variation was analyzed during AI treatment, as well as the differences those patients who were treated and not treated previously with tamoxifen (TMX). Three polymorphisms (rs4077581, rs11632698 and rs900798) of the CYP11A1 gene were genotyped for their association with BMD variation. Results: TMX-treated patients presented more rapid BMD loss than those who did not undergo prior TMX treatment (60% less in spine and 46% in femur at 2 years and 70% less in the spine and 63% in the femur at 3 years). However, no significant BMD loss was detected after treatment in either group. The 3 CYP11A1 gene polymorphisms were significantly associated with BMD variation in the femur at the end of the treatment. Conclusions: BMD was reduced more rapidly in patients with prior TMX treatment than in those who only received AI, although no significant differences were detected after treatment. The 3 CYP11A1 gene polymorphisms were associated with BMD variation in response to AI treatment. [ABSTRACT FROM AUTHOR]

Genetic studies of osteoporosis have focused on analysing single polymorphisms in individual genes – with inconclusive results. An alternative approach may involve haplotypes and gene-gene interactions. The aim of the study was to test the association between the COL1A1, ESR1, VDR and TGFB1 polymorphisms or haplotypes and bone mineral density (BMD) in Spanish postmenopausal women. Sixteen polymorphisms were analysed in 719 postmenopausal women. ANOVA, ANCOVA and Xi2 tests were used to perform the statistical analysis. COL1A1 -1997G > T ( p = 0.04) and TGFB1 Leu10Pro ( p = 0.02) were found to be associated with adjusted lumbar spine (LS) BMD. Interactions were observed between: the COL1A1 -1997 G/T and Sp1 polymorphisms ( p < 0.01 for LS BMD) and the COL1A1 -1663 indelT and VDR ApaI polymorphisms ( p < 0.01 for femoral neck (FN) BMD). The COL1A1 GDs and ESR1 LPX haplotypes were associated with FN BMD ( p = 0.03 and p = 0.03). Polymorphisms at COL1A1 and TGFB1 and haplotypes at COL1A1 and ESR1 were found to be associated with BMD in a cohort of postmenopausal Spanish women. Moreover, COL1A1 polymorphisms showed significant interactions among them and with the VDR 3′ polymorphisms. [ABSTRACT FROM AUTHOR]