Recombinant growth hormone therapy for prepubertal children with idiopathic short stature in Korea: a phase III randomized trial

Effects of growth hormone therapy on the onset and progression of pubertal development in girls with idiopathic short stature

OBJECTIVE

The aim of this study was to explore the impact of growth hormone (GH) therapy on the onset and progression of puberty in girls with idiopathic short stature.

METHODS

This study included 541 girls aged between 4.5 and 10.6 years who were receiving GH treatment, monitored over a 22-year follow-up period. Of these, 126 girls have been followed up to the onset of menarche. The participants were divided into two groups: a ISS control group (n = 66) and a group receiving daily GH treatment at a dose of 0.15 iu/kg (n = 60). We assessed the pubertal development and GH usage of these girls every three months.

RESULTS

(1) There was no significant difference in the onset of puberty between the growth hormone (GH) treatment group and the control group; however, the average duration of puberty was longer in the treatment group compared to the control group. (2) During puberty, there were no significant differences in height growth between the treated and untreated groups. (3) The duration of GH treatment showed a significant negative correlation with the age at onset of gonadal development and the age at menarche in females within the treatment group.

CONCLUSION

GH treatment does not seem to accelerate the onset of puberty but may extend its duration, without significantly impacting height growth during puberty. Additionally, longer GH treatment duration is linked to earlier gonadal development and menarche in females.

Investigating Novel Therapeutic Approaches for Idiopathic Short Stature: Targeting siRNA and Growth Hormone Delivery to the Growth Plate Using Exosome Nanoparticles

Idiopathic short stature (ISS) is a common childhood condition with largely unknown underlying causes. Recent research highlights the role of circulating exosomes in the pathogenesis of various disorders, but their connection to ISS remains unexplored. In the experiments, human chondrocytes are cocultured with plasma exosomes from ISS patients, leading to impaired chondrocyte growth and bone formation. Elevated levels of a specific long non-coding RNA (lncRNA), ISSRL, are identified as a distinguishing factor in ISS, boasting high specificity and sensitivity. Silencing ISSRL in ISS plasma exosomes reverses the inhibition of chondrocyte proliferation and bone formation. Conversely, overexpression of ISSRL in chondrocytes impedes their growth and bone formation, revealing its mechanism of action through the miR-877-3p/GZMB axis. Subsequently, exosomes (CT-Exo-siISSRL-oeGH) with precise cartilage-targeting abilities are engineered, loaded with customized siRNA for ISSRL and growth hormone. This innovative approach offers a therapeutic strategy to address ISS by rectifying abnormal non-coding RNA expression in growth plate cartilage and delivering growth hormone with precision to promote bone growth. This research provides valuable insights into ISS diagnosis and treatment, highlighting the potential of engineered exosomes.

Height outcomes in Korean children with idiopathic short stature receiving growth hormone treatment

Objectives

Growth hormone (GH) therapy's capacity to increase height velocity and height at the end of the study in children with idiopathic short stature (ISS) is controversial. We aimed to investigate the height standard deviation score (SDS) and height velocity of patients with ISS in Korea who received GH treatment.

Methods

We retrospectively reviewed and performed linear mixed model and survival analyses on data from 12 tertiary hospitals in Korea, including subjects diagnosed with ISS from January 2009 to September 2019, treated with GH therapy for more than 6 months, and who were at a pre-pubertal state at the time of diagnosis.

Results

We included 578 children (330 boys and 248 girls). The mean daily dose of GH in this study was 0.051 mg/kg, which was lower than the approved dose in Korea of 0.062 - 0.067 mg/kg. Height SDS was higher in patients who started treatment before the age of 6 years. The probability of reaching the target SDS (-1 SDS) from the beginning of treatment to 2-3 years after its start was higher in children starting treatment before the age of 6 years. The hazard ratio to reach the target SDS (-1 SDS) when using automatic pen or electronic devices was 1.727 times higher than that when using the needle and syringe device.

Conclusion

ISS patients should start GH treatment at an early age, and even lower-than-recommended drug doses may be effective. The selection of automatic pen or electronic device can have a positive effect on reaching the target height SDS.

LCN2 is a new diagnostic biomarker and potential therapeutic target in idiopathic short stature

Idiopathic short stature (ISS) is the most common paediatric endocrine disease. However, the underlying pathology of ISS remains unclear. Currently, there are no effective diagnostic markers or therapeutic strategies available for ISS. In this study, we aimed to identify differential plasma protein expression and novel biomarkers in patients with ISS, and elucidate the biological functions of candidate proteins in ISS pathogenesis. Four specimen pairs from four ISS children and age‐/sex‐matched control individuals were subjected to proteomics analysis, and 340 samples of children with a mean age 9.73 ± 0.24 years were utilized to further verify the differentially expressed proteins by enzyme‐linked immunosorbent assay (ELISA). The receiver‐operating characteristic (ROC) curve and the area under the ROC curve (AUC) were plotted. A total of 2040 proteins were identified, of which 84 were differentially expressed. In vitro and in vivo experiments confirmed the biological functions of these candidate proteins. LCN2 overexpression in ISS was verified using ELISA. Meanwhile, LCN2 showed high sensitivity and specificity in discriminating children with ISS from those with growth hormone deficiency, precocious puberty and normal control individuals. The upregulated expression of LCN2 not only suppressed food intake but also impaired chondrocyte proliferation and bone growth in chondrocytes and rats. As a result, the rats presented a short‐stature phenotype. Subsequently, we found that bone growth inhibition recovered after LCN2 overexpression was stopped in immature rats. To our knowledge, this is the first study to report that LCN2 may be a significant target for ISS diagnosis and treatment.

A Randomized Controlled Phase 3 Study on the Efficacy and Safety of Recombinant Human Growth Hormone in Children With Idiopathic Short Stature

BACKGROUND

To evaluate the safety and efficacy of daily somatropin (Jintropin^®), a recombinant human growth hormone, in prepubertal children with ISS in China.

METHODS

This study was a multicenter, randomized, controlled, open-label, phase 3 study. All subjects were randomized 3:1 to daily somatropin 0.05 mg/kg/day or no treatment for 52 weeks. A total of 481 subjects with a mean baseline age of 5.8 years were enrolled in the study. The primary endpoint was change in (△) height standard deviation score (HT-SDS) for chronological age (CA). Secondary endpoints included △height from baseline; △bone age (BA)/CA; △height velocity (HV) and △insulin-like growth factor 1 (IGF-1 SDS).

RESULTS

△HT-SDS at week 52 was 1.04 ± 0.31 in the treatment group and 0.20 ± 0.33 in the control group (P < 0.001). At week 52, statistical significance was observed in the treatment group compared with control for △height (10.19 ± 1.47 cm vs. 5.85 ± 1.80 cm; P < 0.001), △BA/CA (0.04 ± 0.09 vs. 0.004 ± 0.01; P < 0.001), △HV (5.17 ± 3.70 cm/year vs. 0.75 ± 4.34 cm/year; P < 0.001), and △IGF-1 SDS (2.31 ± 1.20 vs. 0.22 ± 0.98; P < 0.001). The frequencies of treatment-emergent adverse events (TEAEs) were similar for the treatment and the control groups (89.8% vs. 82.4%); most TEAEs were mild to moderate in severity and 23 AEs were considered study-drug related.

CONCLUSIONS

Daily subcutaneous administration of somatropin at 0.05 mg/kg/day for 52 weeks demonstrated improvement in growth outcomes and was well tolerated with a favorable safety profile.

TRIAL REGISTRATION

ClinicalTrials.gov (identifier: NCT03635580). URL: https://clinicaltrials.gov/ct2/show/NCT03635580.

Circular RNA circANAPC2 mediates the impairment of endochondral ossification by miR-874-3p/SMAD3 signalling pathway in idiopathic short stature

Idiopathic short stature (ISS) is a main reason for low height among children. Its exact aetiology remains unclear. Recent findings have suggested that the aberrant expression of circRNAs in peripheral blood samples is associated with many diseases. However, to date, the role of aberrant circRNA expression in mediating ISS pathogenesis remains largely unknown. The up-regulated circANAPC2 was identified by circRNA microarray analysis and RT-qPCR. Overexpression of circANAPC2 inhibited the proliferation of human chondrocytes, and cell cycle was arrested in G1 phase. The expressions of collagen type X, RUNX2, OCN and OPN were significantly down-regulated following circANAPC2 overexpression. Moreover, Von Kossa staining intensity and alkaline phosphatase activity were also decreased. Luciferase reporter assay results showed that circANAPC2 could be targeted by miR-874-3p. CircANAPC2 overexpression in human chondrocytes inhibits the expression of miR-874-3p. The co-localization of circANAPC2 and miR-874-3p was confirmed in both human chondrocytes and murine femoral growth plates via in situ hybridization. The rescue experiment demonstrated that the high expression of miR-874-3p overexpression antagonized the suppression of endochondral ossification, hypertrophy and chondrocyte growth caused by circANAPC2 overexpression. A high-throughput screening of mRNA expression and RT-qPCR verified SMAD3 demonstrated the highest different expressions following overcircANAPC2. Luciferase reporter assay results indicated that miR-874-3p could be targeted by Smad3, thus down-regulating the expression of Smad3. Subsequent rescue experiments of SMAD3 further confirmed that circANAPC2 suppresses endochondral ossification, hypertrophy and chondrocyte growth through miR-874-3p/Smad3 axis. The present study provides evidence that circANAPC2 can serve as a promising target for ISS treatment.

Hsa_circularRNA_0079201 suppresses chondrocyte proliferation and endochondral ossification by regulating the microRNA‑140‑3p/SMAD2 signaling pathway in idiopathic short stature

Circular (circ)RNAs are an important group of non‑coding RNAs involved in different pathological and physiological functions, such as longitudinal bone growth. However, the effects of an increase or decrease in circRNA expression on idiopathic short stature (ISS) remain largely unknown. The present study compared the circRNA expression patterns of patients with ISS and healthy individuals to identify differentially expressed circRNAs involved in the regulation of ISS pathogenesis and their target microRNAs (miR). Microarray analysis revealed that 145 circRNAs were differentially expressed in patients with ISS, including 83 up‑ and 62 downregulated circRNAs. Reverse transcription‑quantitative PCR confirmed that hsa_circRNA_0079201 was increased in patients with ISS compared with that in the normal individuals, whilst hsa_circRNA_0079201 overexpression in human chondrocytes was shown to significantly suppress their proliferation, hypertrophy and endochondral ossification abilities. Luciferase reporter assays identified that circRNA_0079201 acted as an miR‑140‑3p sponge. In situ hybridization confirmed the co‑localization of circRNA_0079201 and miR‑140‑3p in the human chondrocyte and neonatal femur growth plate of C57 mice, while rescue experiments demonstrated that miR‑140‑3p overexpression reversed the inhibition of human chondrocyte proliferation, hypertrophy and endochondral ossification, caused by circRNA_0079201 overexpression. Bioinformatics analysis and luciferase reporter assays revealed that SMAD2 was a potential target gene of miR‑140‑3p. Furthermore, overexpressing circRNA_0079201 in human chondrocytes suppressed miR‑140‑3p and increased SMAD2 protein expression level. Taken together, chondrocyte proliferation, hypertrophy and endochondral ossification in ISS was suppressed by a novel regulatory axis consisting of the hsa_circRNA_0079201/miR‑140‑3p/SMAD2 pathway. The present study provided evidence that hsa_circRNA_0079201 may be a potential target for ISS therapy.

Effect of -202 A/C IGFBP-3 polymorphisms on growth responses in children with idiopathic short stature

PURPOSE

This study evaluated the -202 A/C insulin-like growth factor binding protein 3 (IGFBP-3) promoter polymorphism as a predictor of serum IGFBP-3 concentration and growth velocity after recombinant growth hormone (rhGH) therapy in patients with idiopathic short stature (ISS).

METHODS

Genotyping and serial measurement of clinical parameters were performed in 69 children with a confirmed diagnosis of ISS. Restriction fragment length polymorphism analysis was performed to determine the genotype at the -202 IGFBP-3 locus. Serum insulin-like growth factor 1 (IGF-1) and IGFBP-3 levels were measured at baseline and after 1 year of rhGH treatment, as were height standard deviation score and growth velocity.

RESULTS

The -202 A/C IGFBP-3 genotype comprised 69.6% AA, 24.6% AC, and 5.8% CC. One year of treatment did not produce a meaningful difference in IGF-1 or IGFBP-3 levels between children in the AA group and those with at least one copy of the C allele (AC/CC group). Comparing the 2 groups after one year also revealed no significant difference in growth velocity (ΔHeight: 9.061±1.612 cm/yr in the AA group, 9.421±1.864 in the AC/CC group, P=0.419).

CONCLUSION

rhGH treatment was effective and there were no significant differences in IGF-1, IGFBP-3, or growth velocity according to genotype. Thus, -202 IGFBP-3 genotype may not be a major factor affecting individual growth responses in Korean children with ISS.

First-year predictors of health-related quality of life changes in short-statured children treated with human growth hormone

PURPOSE

Little attention has been directed towards examining the impact of predictors on change in health-related quality of life (HRQOL) within the course of growth hormone (GH) treatment in pediatric short stature. We aimed to assess changes in HRQOL and its sociodemographic, clinical and psychosocial predictors in children and adolescents diagnosed with growth hormone deficiency (GHD), and born short for gestational age (SGA) before and 12-month after start of GH treatment from the parents' perspective. Results were compared with an untreated group with idiopathic short stature (ISS). In this prospective multicenter study, 152 parents of children/adolescents (aged 4-18 years) provided data on their children's HRQOL at baseline and at 12-month follow-up.

METHOD

Repeated-measures multivariate analyses of covariance were performed to examine parent-reported HRQOL changes from baseline to 1-year after treatment and hierarchical linear regressions to identify the predictors of HRQOL changes.

RESULTS

Results showed that parents of children that were treated with GH report an increase in their children's HRQOL after 1 year. Changes in HRQOL were mostly explained by psychosocial predictors followed by sociodemographic and clinical variables. Specifically, the diagnosis SGA significantly predicted a greater increase in parent-reported HRQOL. Furthermore, a lower caregiving burden significantly predicted a decrease in parent-reported HRQOL.

CONCLUSION

In conclusion, a substantial percentage of explained variance in HRQOL relates to psychosocial and sociodemographic predictors. However, there appears to be other important factors that are predictors of HRQOL, which need to be determined in large, population-based samples.