Adolescent Bone Research Articles

One half-century of advances in the evaluation and management of disorders of bone and mineral metabolism in children and adolescents.

The past 50years of research in pediatric bone and mineral metabolism have led to remarkable progress in the identification and characterization of disorders that affect the developing skeleton. Progress has been facilitated through advances in both technology and biology and this paper provides a brief description of some but not all of the key findings, including identification of the calcium sensing receptor and the polypeptides parathyroid hormone and parathyroid hormone-related protein as well as their shared receptor and signal generating pathways; the elucidation of vitamin D metabolism and actions; discovery of fibroblast growth factor 23 (FGF23), the sodium-phosphate co-transporters and the other components that regulate phosphate metabolism. Moreover, the past half-century of research has led to the delineation of the molecular bases for genetic forms ofhypoparathyroidism, pseudohypoparathyroidism, and primary hyperparathyroidism as well as the determination of the genetic causes of osteogenesis imperfecta, osteopetrosis, hypophosphatasia, and other disorders of mineral/bone homeostasis. During the next decade we expect that many of these fundamental discoveries will lead to the development of innovative treatments that will improve thelives of children with these disorders.

Retracted: Influence of Sports Intervention Based on K-Center Algorithm on Adolescent Obesity Metabolism and Bone Quality.

[This retracts the article DOI: 10.1155/2021/9236369.].

Analysis of scRNA-seq and bulk RNA-seq demonstrates the effects of EVI2B or CD361 on CD8+ T cells in osteosarcoma.

Osteosarcoma (OS) is a common primary malignant tumor of the bone in children and adolescents. The five-year survival rate is estimated to be ~70% based on the currently available treatment modalities. It is well known that tumor-infiltrating immune cells (TIICs) that are the most important components in the tumor microenvironment can exert a killing effect on tumor cells. Therefore, in the present study, 85 RNA-sequencing OS samples were categorized into high- and low-immune score groups with ESTIAMATE. Based on the immune score groups, 474 differentially expressed genes (DEGs) were acquired using the LIMMA package of R language. Subsequently, 86 DEGs were taken through univariate COX regression analysis, of which 14 were screened out by least absolute shrinkage and selection operator regression analysis. Furthermore, multivariate COX regression analysis was performed to obtain 4 DEGs. Finally, ecotropic virus integration site 2B (EVI2B) or CD361 gene was screened out via Kaplan-Meier analysis. In addition, CIBERSORT algorithm was used to evaluate the proportion of 22 kinds of TIICs in OS. Correlation analysis revealed that the high expression level of EVI2B can elevate the infiltrated proportion of CD8+ T cells. Moreover, analysis of single cell RNA-sequencing transcriptome datasets and immunohistochemical staining uncovered that EVI2B was mainly expressed on CD8+ T cells and that EVI2B could promote the expression of granzyme A and K of CD8+ T cells to exhibit a potent killing effect on tumor cells. Therefore, EVI2B was identified as a protective immune-related gene and contributed to good prognosis in OS patients.

TIPE1 inhibits the growth of Ewing's sarcoma cells by suppressing Wnt/β-catenin signaling.

Ewing's sarcoma is the second most common bone and soft tissue malignancy in children and adolescents. Tumor necrosis factor-α-induced protein 8-like 1 (TIPE1) functions as a tumor suppressor in several cancers. Activation of Wnt/β-catenin signaling in subpopulations of tumor cells contributes to phenotypic heterogeneity and disease progression in Ewing's sarcoma. The exact role of TIPE1 in Ewing's sarcoma remains to be elucidated. This study aimed to assess the expression and function of TIPE1 in Ewing's sarcoma. TIPE1 expression in Ewing's sarcoma cells was determined by qPCR and western blotting. Furthermore, the Ewing's sarcoma cell line RD-ES was transfected with a lentivirus-based TIPE1 expression system to upregulate the expression of TIPE1. The Cell Counting Kit 8 was used to assess the effect of TIPE1 on cell proliferation. The effects of TIPE1 on cell migration and invasion was detected by Transwell assay. Flow cytometry was performed to detect apoptosis. Our results suggested lower TIPE1 expression in Ewing's sarcoma cell lines compared with normal osseous cells. TIPE1 remarkably inhibited the growth and proliferation of Ewing's sarcoma cell; TIPE1 also induced apoptosis and inhibited invasion in vitro. TIPE1 inhibited Ewing's sarcoma growth, motility, and survival through regulation of Wnt/β-catenin signaling. Our results demonstrated the anti-tumor function of TIPE1 in Ewing's sarcoma and reveal a novel therapeutic target.

Development and validation of a cuproptosis-related lncRNA model correlated to the cancer-associated fibroblasts enable the prediction prognosis of patients with osteosarcoma

BackgroundOsteosarcoma is the most common primary pediatric and adolescent bone malignancy. An imbalance in copper homeostasis caused by copper ion accumulation could increase intracellular toxicity and regulate cancer cell growth. This study aimed to identify long non-coding RNAs (lncRNAs) associated with cuproptosis to predict prognosis and target drug use to improve patient survival. MethodsRNA sequencing and relevant clinical information of ninety-three osteosarcoma patients were obtained from the TARGET database. We then identified thirteen prognostic cuproptosis-related lncRNAs(CRLncs) using coexpression and univariate Cox analyses. The prognostic risk model with three CRLncs was constructed using the least absolute shrinkage and selection operator (LASSO) and multivariate Cox regression analysis. Patients were divided into low-risk and high-risk subgroups using the median risk score. The tumor microenvironment (TME) and immune status of identified subgroups were analyzed using ESTIMATE, CIBERSORT, MCP-counter, xCELL, EPIC, and ssGSEA analyses. Functional analyses were conducted to elucidate the underlying mechanisms, including GO, KEGG, GSVA, and GSEA analyses. Also, the relationships between the model, tumor immunity, and drug sensitivity were explored. Lastly, the expression level of ZNF37BP, AL353759.1, and AC005034.5 was validated in vitro. ResultsWe constructed a model containing three CRLncs (ZNF37BP, AL353759.1, and AC005034.5) and validated its excellent prognostic and predictive power. The AUC curves for 1-year, 3-year, and 5-year survival probabilities were 0.76, 0.84, and 0.89, respectively. Patients in the high-risk group had a shorter overall survival (OS) time than those in the low-risk. The stroma score and cancer-associated fibroblasts (CAFs) were significantly higher in the low-risk group. Immune cells such as T cells CD4 naive, T cells gamma delta, NK cells resting, dendritic cells resting, and mast cells activated were significantly upregulated in the high-risk group. Based on functional analyses, the PI3K-Akt pathway was identified as a critical metabolic pathway in osteosarcoma. Additionally, we obtained three potentially effective drugs for OS: erlotinib, MP470, and WH-4-023 targeting the PI3K-Akt pathway. The expression level of ZNF37BP was significantly elevated in OS cell lines than in normal osteoblast hFOB1.19 cells, and that of ATP7A, LIPT1, AL353759.1, and AC005034.5 were decreased considerably in OS cell lines. ConclusionCuproptosis-related lncRNAs are correlated with the CAFs of osteosarcoma, and this could serve as a foundation for OS survival prediction and treatment.

ALTERAÇÕES NA DENSIDADE ÓSSEA DOS MEMBROS INFERIORES EM JOVENS PRATICANTES DE SALTO

ABSTRACT Introduction The research on the exercise effect on the human bone density and skeletal muscle content mainly focuses on the middle-aged and elderly population. However, few studies on different sports’ effects upon bone and muscle density in college students and adolescents. Objective Study the effect of physical training on bone density and lower limb jumping ability in young people. Methods The relationship between bone mineral density and lower limb jumping ability was analyzed by mathematical statistics. Male individuals aged 10-20 years were divided into the early adolescence group (n=26) and late adolescence group (n=37). According to training status, they were divided into preadolescent athletic group (n=11), non-athletic group (n=15); puberty athletic group (n=11) and non-athletic group (n=15). The following indicators were used: bone density, vertical jump test, continuous vertical jump test, RDJ index. Results Athletes’ bone mineral density (BMD) is related to their muscle strength. These results suggest a certain internal connection between the (BMD) of bone tissue and the development of muscle strength. Therefore, there is evidence of differences in lower limb bone mineral density and jumping ability between the two groups. Conclusion Bone mineral density in the lower limbs of adolescents is correlated with jumping ability. Exercise can help improve bone density in adolescents. Evidence level II; Therapeutic Studies - Investigating the results.

Anterior Dental Implant in Grafted Cleft Alveolus: A Clinical Comparison Between Intramembranous and Endochondral Bone Graft.

Alveolar bone graft is usually performed during the early mixed dentition phase, at the chronological age of 6 to 8 years old, to reconstruct the cleft alveolus. As the appropriate time for implant placement is after completion of full growth, it can result in a likelihood of resorption. The aim of this study is to compare the clinical outcomes of anterior dental implants with delayed bone grafting using iliac crest (endochondral) and mandibular ramus or symphysis (intramembranous) bone in adolescents to adulthood patients with cleft alveolus. This study included 10 patients with cleft alveolus who underwent delayed bone grafting with autogenous block bone and particulate cancellous bone and marrow (PCBM) from the mandibular ramus and symphysis with dental implant placement, and iliac crest. The success of the treatment was evaluated through clinical and radiographic examination including marginal bone loss measurement of the implants. All patients underwent delayed bone grafting between the ages of 11 and 21.1 years (mean age: 15.1±4.3y). The implant diameters ranged from 3.8 to 4.5mm and the lengths ranged from 8.0 to 11.5mm. All of the implants were integrated successfully and survived during the 3-year follow-up period. Delayed bone grafting followed by implant placement showed long-term stability with satisfactory esthetic and functional rehabilitation. One of the main advantages of delayed bone grafting is to achieve adequate bone support for future dental implant placements with less bone resorption compared with those of primary, early secondary, and secondary bone grafting.

Altered bone and body composition in children and adolescents with confirmed prenatal alcohol exposure.

Prenatal alcohol exposure can contribute to long term adverse health outcomes. Development of the skeletal system begins at the early embryonic stage and continues into early adulthood but the effect of prenatal alcohol exposure on skeletal growth is relatively unexplored in a clinical population. Here, we performed dual X-ray absorptiometry to examine bone, fat, and muscle accrual in children and adolescents diagnosed with, or at risk of, fetal alcohol spectrum disorders (FASDs). Children (aged 4-9years) with FASD or at risk of FASD (n=10) had similar growth to age matched controls (n=27). By adolescence (aged ≥10years), those with FASDs (n=13) were shorter and had lower areal bone mineral density and lean tissue mass than typically developing peers (n=29). Overall, adolescents diagnosed with FASDs had greater odds of impairments to bone and body composition. These findings highlight the importance of early FASD diagnosis and appropriate post-diagnostic medical follow-up to enable timely, effective interventions to optimize bone and body composition during paediatric growth.

Regulation of Molecular Targets in Osteosarcoma Treatment.

The most prevalent malignant bone tumor, osteosarcoma, affects the growth plates of long bones in adolescents and young adults. Standard chemotherapeutic methods showed poor response rates in patients with recurrent and metastatic phases. Therefore, it is critical to develop novel and efficient targeted therapies to address relapse cases. In this regard, RNA interference technologies are encouraging options in cancer treatment, in which small interfering RNAs regulate the gene expression following RNA interference pathways. The determination of target tissue is as important as the selection of tissue-specific promoters. Moreover, small interfering RNAs should be delivered effectively into the cytoplasm. Lentiviral vectors could encapsulate and deliver the desired gene into the cell and integrate it into the genome, providing long-term regulation of targeted genes. Silencing overexpressed genes promote the tumor cells to lose invasiveness, prevents their proliferation, and triggers their apoptosis. The uniqueness of cancer cells among patients requires novel therapeutic methods that treat patients based on their unique mutations. Several studies showed the effectiveness of different approaches such as microRNA, drug- or chemotherapy-related methods in treating the disease; however, identifying various targets was challenging to understanding disease progression. In this regard, the patient-specific abnormal gene might be targeted using genomics and molecular advancements such as RNA interference approaches. Here, we review potential therapeutic targets for the RNA interference approach, which is applicable as a therapeutic option for osteosarcoma patients, and we point out how the small interfering RNA method becomes a promising approach for the unmet challenge.

Effect of obesity status on adolescent bone mineral density and saturation effect: A cross-sectional study.

BackgroundThe effect of obesity status on bone mineral density (BMD) in adolescents and whether there is a saturation effect is still insufficient. A cross-sectional study of adolescents aged 12–19 was conducted to investigate them.MethodsWeighted multivariate linear regression models were used to assess the relationship between obesity status and BMD via datasets from the National Health and Nutrition Examination Survey 2011–2018. The nonlinear relationships and saturation values were ascertained by fitting smooth curves and analyzing saturation effects. At the same time, the subgroup stratified analysis was also performed.Results4056 adolescents were included in this study. We found that body mass index (BMI) and waist circumference (WC) were significantly associated with total BMD, which remained significant in subgroups stratified by age, gender, standing height, and ethnicity. We also noticed an inverse correlation between left leg fat/lean mass and left leg BMD, which was only significant in males and other races. Fitting smooth curve and saturation effect analysis showed that BMI, WC, left leg fat/lean mass, and BMD had a specific saturation effect. There was a saturation effect on bone mineral density in adolescents with a BMI of 22 kg/m2, a WC of 70.5 cm, or a left leg fat/lean mass of 0.2994.ConclusionsWe found a positive saturation effect of BMI and WC with BMD and a negative saturation effect of left leg fat/lean mass with BMD. Appropriate obesity status allows adolescents to have better bone mass development but not excessive obesity.

Regulation of Metastasis in Ewing Sarcoma.

Simple SummaryEwing sarcoma (EwS) is the second most common bone and soft tissue cancer which mainly happens in children and adolescents. Currently, EwS patients are treated with a combination of surgery, radiation, and interval compressed chemotherapy. While outcomes have improved over the last several decades for patients with localized diseases, little progress has been made in the treatment of patients with newly diagnosed metastatic or relapsed diseases. Moreover, in localized cases, the survival rates are around 70% after five years and 30% after ten years. However, one third of patients develop metastatic tumor and, when metastasis is diagnosed, the five-year survival rates drop sharply to 25%. There is, therefore, urgent need to dissect the regulatory mechanism of EwS tumor metastasis and thus develop treatment strategies to treat metastatic diseases. Here, we reviewed the regulation of metastasis in EwS and hoped this can guide future studies on metastasis.Ewing sarcoma (EwS) is a type of bone and soft tissue tumor in children and adolescents. Over 85% of cases are caused by the expression of fusion protein EWSR1-FLI1 generated by chromosome translocation. Acting as a potent chimeric oncoprotein, EWSR1-FLI1 binds to chromatin, changes the epigenetic states, and thus alters the expression of a large set of genes. Several studies have revealed that the expression level of EWSR1-FLI1 is variable and dynamic within and across different EwS cell lines and primary tumors, leading to tumoral heterogeneity. Cells with high EWSR1-FLI1 expression (EWSR1-FLI1-high) proliferate in an exponential manner, whereas cells with low EWSR1-FLI1 expression (EWSR1-FLI1-low) tend to have a strong propensity to migrate, invade, and metastasize. Metastasis is the leading cause of cancer-related deaths. The continuous evolution of EwS research has revealed some of the molecular underpinnings of this dissemination process. In this review, we discuss the molecular signatures that contribute to metastasis.

A Comparison of 2 Abbreviated Methods for Assessing Adolescent Bone Age: The Shorthand Bone Age Method and the SickKids/Columbia Method.

Radiographic assessment of bone age is critically important to decision-making on the type and timing of operative interventions in pediatric orthopaedics. The current widely accepted method for determining bone age is time and resource-intensive. This study sought to assess the reliability and accuracy of 2 abbreviated methods, the Shorthand Bone Age (SBA) and the SickKids/Columbia (SKC) methods, to the widely accepted Greulich and Pyle (GP) method. Standard posteroanterior radiographs of the left hand of 125 adolescent males and 125 adolescent females were compiled, with bone ages determined by the GP method ranging from 9 to 16 years for males and 8 to 14 years for females. Blinded to the chronologic age and GP bone age of each child, the bone age for each radiograph was determined using the SBA and SKC methods by an orthopaedic surgery resident, 2 pediatric orthopaedic surgeons, and a musculoskeletal radiologist. Measurements were then repeated 2 weeks later after rerandomization of the radiographs. Intrarater and interrater reliability for the 2 abbreviated methods as well as the agreement between all 3 methods were calculated using weighted κ values. Mean absolute differences between methods were also calculated. Both bone age methods demonstrated substantial to almost perfect intrarater reliability, with a weighted κ ranging from 0.79 to 0.93 for the SBA method and from 0.82 to 0.96 for the SKC method. Interrater reliability was moderate to substantial (weighted κ: 0.55 to 0.84) for the SBA method and substantial to almost perfect (weighted κ: 0.67 to 0.92) for the SKC method. Agreement between the 3 methods was substantial for all raters and all comparisons. The mean absolute difference, been GP-derived and SBA-derived bone age, was 7.6±7.8 months, as compared with 8.8±7.4 months between GP-derived and SKC-derived bone ages. The SBA and SKC methods have comparable reliability, and both correlate well to the widely accepted GP methods and to each other. However, they have relatively large absolute differences when compared with the GP method. These methods offer simple, efficient, and affordable estimates for bone age determination, but at best provide an estimate to be used in the appropriate setting. Diagnostic study-level III.

Ewing's Sarcoma of the Gastrointestinal Tract—A Case Series

Ewing's sarcoma is a neoplasm of the undifferentiated small round cells, which generally affects the bone and deep soft tissues of children and adolescents. Extraskeletal Ewing's sarcomas are less common than skeletal Ewing's sarcoma with the most common sites being chest wall, retroperitoneal space, lower extremities, paravertebral region, and gluteal region. Primary Ewing's sarcoma of the gastrointestinal tract is rare. The rarity of cases, lack of specific literature, or guidelines for treatment and varying presentations make these cases challenging to diagnose and to treat. In this series, we share our experience from a tertiary cancer care center in South India. By our knowledge, this is the first case series in literature sharing the experience from a single center in treating four cases of gastrointestinal Ewing's sarcoma.

Early life organophosphate ester exposures and bone health at age 12 years: The Health Outcomes and Measures of the Environment (HOME) Study

BackgroundNo human studies have evaluated early life organophosphate ester (OPE) exposures with bone health outcomes, despite evidence of osteotoxicity. ObjectivesWe assessed associations of urinary OPE metabolites measured across early life with areal bone mineral density (aBMD) and bone mineral content (BMC) at age 12 years. MethodsAmong 223 mother-child dyads enrolled in the Health Outcomes and Measures of the Environment (HOME) Study, we quantified concentrations of bis-2-chloroethyl phosphate (BCEP), bis-(1,3-dichloro-2-propyl) (BDCIPP), di-n-butyl phosphate (DnBP), and diphenyl phosphate (DPHP) in urine collected from mothers during pregnancy and children at ages 1, 2, 3, 5, and 8 years. At age 12 years, we performed dual energy x-ray absorptiometry and calculated aBMD and BMC z-scores at six skeletal sites. We estimated overall and sex-stratified BMD/BMC z-score differences per interquartile range (IQR) increase in OPE concentrations at multiple exposure timepoints: gestation (average) and 1–3 (average), 5, and 8 years. ResultsIn adjusted models, overall associations of BCEP and BDCIPP with total hip and 1/3rd distal radius aBMD and BMC varied significantly by exposure timepoint, as did BDCIPP with whole body aBMD. For example, differences (95 % CI) in total hip aBMD z-score per IQR increase in BDCIPP were 0.33 (0.01, 0.64), −0.10 (−0.34, 0.14), −0.18 (−0.40, 0.05), and 0.14 (−0.09, 0.38) for concentrations during gestation and at 1–3, 5, and 8 years, respectively. Overall DnBP and DPHP associations were generally null at all timepoints. We observed sex-specific associations for some timepoints and skeletal sites. For example, an IQR increase in 8-year DPHP was associated with a 0.21 (0.05, 0.38) greater total hip aBMD z-score among females but −0.19 (−0.43, 0.05) lower z-score among males. DiscussionEarly life OPE exposures may be associated with sex- and exposure period-dependent alterations in early adolescent bone mineral accrual and strength.

Review study on benefits of calcium supplementation on adolescent Bone mineral density

Because of the new distribution of two epidemiological investigations and one meta-examination of randomized controlled clinical preliminaries, the relationship between calcium supplementation and antagonistic cardiovascular occasions has as of late turned into a subject of discussion. The reports demonstrate that there is a critical expansion in antagonistic cardiovascular occasions following supplementation with calcium; notwithstanding, various specialists have raised various issues with these reports, for example, irregularities in endeavors to duplicate the discoveries in different populaces and questions concerning the legitimacy of the information because of low consistence, predispositions on the off chance that ascertainment, and additionally an absence of change. The reports demonstrate that there is a huge expansion in antagonistic cardiovascular occasions following supplementation with calcium; notwithstanding, these reports have been reprimanded for furthermore, the Women's Health Initiative, the Auckland Calcium Study, and a significant number of different investigations that were remembered for the meta-examination acquired information from subjects who had calcium levels that were inside the ordinary reach. Along these lines, it is indistinct whether a similar gamble profile would be seen in populaces that had low calcium admissions.

Three-dimensionally rendering of the sphenoid bone of adolescents using Materialise’s Interactive Medical Image Control System software

The main goal of this study was to reconstruct three-dimensionally (3D) the sphenoid bone of adolescents with the software Materialise Mimics to test the accuracy and reliability of craniometric measurements performed with the software. The study was conducted according to Strengthening the Reporting of Observational studies in Epidemiology (STROBE) guidelines. Cone-Beam Computed Tomography (CBCT) was performed in adolescents before the orthodontic treatment as part of the orthodontic records. The CBCT images were exported as DICOM (Digital Imaging and Communication in Medicine) files, in a universal format, with a voxel size of 0.3 mm and sphenoid bone was three-dimensionally rendered with Software Materialise Mimics. Ten sphenoid measurements were performed in triplicate by two trained examiners. The studied population was composed of 26 adolescents, 16 females (61.5%), and 10 males (38.5%) with a mean age of 12.5 years (SD= 1.7). 60 measurements were taken and the intra and inter-examiner accuracy revealed a high degree of data reproducibility (Kappa test higher than 0.90). The reconstruction and rendering of the images obtained by CBTC allowed anatomical details of the sphenoid bone to be measured with very high reproducibility. The Software Materialise Mimics allows you to analyze anatomical structures in detail and presents useful tools to optimize craniometry analyses.

Adequacy of calcium and vitamin D nutritional status in a nationally representative sample of Irish teenagers aged 13–18 years

Context and purposeIn light of the key roles of vitamin D and calcium in adolescent bone health, there is a critical need for representative data on nutritional status for both micronutrients in teenagers. The present work used data from the recent representative National Teens’ Food Survey II (2019–2020) to assess calcium and vitamin D intakes of teenagers in Ireland, including adequacy of such intakes, as well as, for the first time, to characterise serum 25-hydroxyvitamin D (25(OH)D) concentrations and their determinants.MethodsUsual calcium and vitamin D intake estimates were generated using food intake data (via 4-day weighed food records) from a nationally representative sample of teenagers aged 13–18 years in Ireland (n 428). Serum 25(OH)D was measured (via LC–MS/MS) in the 57.5% (n 246) who provided a blood sample.ResultsSixty-seven and 94% of Irish teenagers had intakes of calcium and vitamin D below the respective Estimated Average Requirements values, reflecting a high degree of inadequacy of intake for both micronutrients (and higher in girls than boys; P < 0.001). In addition, 21.7% and 33.1% of teenagers had serum 25(OH)D < 30 nmol/L (risk of vitamin D deficiency) and 30–49.9 nmol/L (inadequacy), respectively. Extended winter sampling, being aged 16–18 years, low total vitamin D intake, being overweight/obese or being of non-white skin type were significant (P < 0.05) predictors of serum 25(OH)D < 30 nmol/L.ConclusionsThere was a high prevalence of inadequacy of intake of calcium and vitamin D in Irish teenagers, and a fifth were at increased risk of vitamin D deficiency.

Research priority setting for paediatric rheumatology in the UK.

The evidence base that underlies the management of children and young people with paediatric rheumatic diseases is deficient. In this field, there are many crucial unanswered questions. The UK Paediatric Rheumatology Clinical Studies Group, supported by UK National Institute for Health Research Clinical Research Network: children and Versus Arthritis, elicited ideas for research priorities from paediatric rheumatologists, trainees, allied health-care professionals, nurse specialists, patients, parents of patients, carers, and charities. These ideas were collected through online surveys and face-to-face meetings. A modified Delphi process was used, which included online research priority ranking surveys and a consensus workshop. A longlist of 55 disease-specific research priorities and 37 general research priorities were voted on in the first survey. A list of 11 top general research priorities was produced. The top ten disease-specific research priorities were discussed in depth at a Delphi workshop to determine their final ranking. This Health Policy paper will help to guide clinicians, academics, and funding bodies to prioritise research in paediatric rheumatic diseases, specifically in areas of unmet patient needs.

Review study on benefits of calcium supplementation on adolescent bone mineral density

Because of the new distribution of two epidemiological investigations and one meta-examination of randomized controlled clinical preliminaries, the relationship between calcium supplementation and antagonistic cardiovascular occasions has as of late turned into a subject of discussion. The reports demonstrate that there is a critical expansion in antagonistic cardiovascular occasions following supplementation with calcium; notwithstanding, various specialists have raised various issues with these reports, for example, irregularities in endeavors to duplicate the discoveries in different populaces and questions concerning the legitimacy of the information because of low consistence, predispositions on the off chance that ascertainment, and additionally an absence of change. The reports demonstrate that there is a huge expansion in antagonistic cardiovascular occasions following supplementation with calcium; notwithstanding, these reports have been reprimanded for furthermore, the Women's Health Initiative, the Auckland Calcium Study, and a significant number of different investigations that were remembered for the meta-examination acquired information from subjects who had calcium levels that were inside the ordinary reach. Along these lines, it is indistinct whether a similar gamble profile would be seen in populaces that had low calcium admissions. Furthermore, the skeletal advantages of calcium supplementation are more noteworthy in subjects with low calcium admissions.

Abstract 6308: Antitumor effects of RBPJ Inhibitor-1 on osteosarcoma cells

Abstract Osteosarcoma (OS) is the most common primary malignancy of the bone in adolescents and children with limited treatment options. Drug resistance to current therapy together with severe side effects urgently calls for alternative treatment strategies targeting critical cancer signaling pathways. Recently, our and other studies suggest that hyperactivation of Notch signaling contributes to the pathogenesis of human and murine OS, and its inhibition may be a therapeutic approach for the treatment of OS. Notch pathophysiological activity involves activated Notch (i.e. NICD, the notch intracellular domain) forming a nuclear complex with DNA-binding factors and coactivators such as recombination signal binding protein for immunoglobulin kappa J region (RBPJ). This evolutionary conserved mechanism is involved in the maintenance and survival of cancer stem cells, which can govern various cell activities like metastasis and chemoresistance. This study aims to examine the in vitro effects of targeting the NICD-RBPJ interaction using a small molecular inhibitor of the RBPJ (RIN1) on osteosarcoma cell lines. We found that treatment of 10 µM RIN1 on SJSA-1 (ATCC, CRL-2098), a human osteosarcoma cell line with a high Notch activity, can significantly decrease cell proliferation at 48 and 72 hours (h). We also found that at 10 µM of RIN1 affects SJSA-1 migration using a Boyden chamber-based cell system at 24 h, a time point where we find minimal contribution from an effect on cell proliferation. Treatment with RIN1 can block SJSA-1 clonogenicity, but we showed that it has limited ability to block SJSA-1 cell invasion. Treatment with RIN1 does not initiate or enhance the osteoblast-like differentiation of SJSA-1. Notch target genes HEY1 and CyclinD1 was significantly modulated in SJSA-1 cells upon treatment in a Notch-independent manner. Interestingly, treatment with RIN1 on SJSA-1 decreases SOX2 protein expression, a well-known cancer stem cell marker, and upregulates tumor suppressor RB1 protein expression. Ongoing studies include additional cellular function assays and RNA-seq transcriptomic analysis of RIN1’s effect on two Notch-dependent cancer cell lines including MB 157 (ATCC, CRL-7721) and T29 in its activating context. In summary, RIN1 has been shown to have a significant effect on the different cell behaviors of human osteosarcoma, which may eventually facilitate with the treatment of patients that have metastatic disease. Citation Format: Dakota Callahan, Leetoria Hinojosa, Haydee M. Torres, Jianning Tao. Antitumor effects of RBPJ Inhibitor-1 on osteosarcoma cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6308.