The human cathelicidin hCAP-18 in serum of children with haemato-oncological diseases

The human cathelicidin hCAP-18 (pro-LL-37) is the pro-protein of the antimicrobial peptide LL-37. hCAP-18 can be produced by many different cell types; bone marrow neutrophil precursors are the main source of hCAP-18 in the circulation. Neutrophil count is used as a marker for myelopoiesis but does not always reflect neutrophil production in the bone marrow, and thus additional markers are needed. In this study, we established the reference interval of serum hCAP-18 level in healthy children and compared serum hCAP-18 levels between different diagnostic groups of children with haemato-oncological diseases, at diagnosis. We found that children with diseases that impair myelopoiesis, such as acute leukaemia, aplastic anaemia, or myelodysplastic syndrome, presented with low hCAP-18 levels, whereas patients with non-haematological malignancies displayed serum hCAP-18 levels in the same range as healthy children. Children with chronic myeloid leukaemia presented with high circulating levels of hCAP-18, probably reflecting the high number of all differentiation stages of myeloid cells. We suggest that analysis of serum hCAP-18 provides additional information regarding myelopoiesis in children with haemato-oncological diseases, which may have future implications in assessment of myelopoiesis in clinical management.Peer reviewe

Vitamin D, bone turnover markers and hCAP-18 in children with hemato-oncological diseases

Children with hemato-oncological diseases may have significant skeletal morbidities. Vitamin D is essential for the maintenance of skeletal health and may also be important for immunological functions and cancer outcomes. As vitamin D deficiency is a recognized problem in children worldwide, it is important to evaluate its prevalence among children and adolescents with hemato-oncological diseases in Sweden. In this thesis, I investigated vitamin D status and its predictors, serum hCAP-18 (the pro-protein of the antimicrobial peptide LL-37 produced during neutrophil differentiation in the bone marrow), and bone turnover markers in children with hemato-oncological diseases at the time of diagnosis.  Vitamin D deficiency was found in 30.9–46% of the children. Lower 25-hydroxyvitamin D level correlated with older age, seasons outside summer, a more recent calendar year of sampling, lack of vitamin D supplementation, and country of parental origin located between latitudes -45° and 45°. In preschool children with leukemia, a 25-hydroxyvitamin D level < 50 nmol/L was associated with inferior overall survival.  There was no correlation between serum 25-hydroxyvitamin D and hCAP-18 neither in children with hemato-oncological diseases nor in healthy controls. Children with diseases that impair myelopoiesis presented low hCAP-18 levels, whereas those with non-hematological malignancies displayed serum hCAP-18 levels in the same range as that of healthy children. Children diagnosed with leukemia had lower levels of bone formation and resorption markers than those of children with solid tumors or bone marrow failure. Adolescents with osteosarcoma displayed high bone alkaline phosphatase levels. The identification of patients with suboptimal vitamin D status and compromised bone remodeling at cancer diagnosis may aid the development of supportive treatments that reduce the adverse effects of cancer and its treatment.

Vitamin D, bone turnover markers and hCAP-18 in children with hemato-oncological diseases

Children with hemato-oncological diseases may have significant skeletal morbidities. Vitamin D is essential for the maintenance of skeletal health and may also be important for immunological functions and cancer outcomes. As vitamin D deficiency is a recognized problem in children worldwide, it is important to evaluate its prevalence among children and adolescents with hemato-oncological diseases in Sweden. In this thesis, I investigated vitamin D status and its predictors, serum hCAP-18 (the pro-protein of the antimicrobial peptide LL-37 produced during neutrophil differentiation in the bone marrow), and bone turnover markers in children with hemato-oncological diseases at the time of diagnosis.  Vitamin D deficiency was found in 30.9–46% of the children. Lower 25-hydroxyvitamin D level correlated with older age, seasons outside summer, a more recent calendar year of sampling, lack of vitamin D supplementation, and country of parental origin located between latitudes -45° and 45°. In preschool children with leukemia, a 25-hydroxyvitamin D level < 50 nmol/L was associated with inferior overall survival.  There was no correlation between serum 25-hydroxyvitamin D and hCAP-18 neither in children with hemato-oncological diseases nor in healthy controls. Children with diseases that impair myelopoiesis presented low hCAP-18 levels, whereas those with non-hematological malignancies displayed serum hCAP-18 levels in the same range as that of healthy children. Children diagnosed with leukemia had lower levels of bone formation and resorption markers than those of children with solid tumors or bone marrow failure. Adolescents with osteosarcoma displayed high bone alkaline phosphatase levels. The identification of patients with suboptimal vitamin D status and compromised bone remodeling at cancer diagnosis may aid the development of supportive treatments that reduce the adverse effects of cancer and its treatment.

Prevalence of and factors influencing vitamin D deficiency in paediatric patients diagnosed with cancer at northern latitudes

Aim To investigate the prevalence of vitamin D deficiency among children with non-haematological malignancies and to explore possible causes of low vitamin D levels among these patients. Methods We performed a cross-sectional study of 458 children diagnosed with solid tumours, brain tumours, non-Hodgkin lymphoma or Hodgkin disease at the University Children's Hospital, Uppsala, Sweden. Serum 25-hydroxyvitamin D and parathyroid hormone levels were measured in samples taken at the time of cancer diagnosis and related to clinical data. Vitamin D deficiency was defined as a 25-hydroxyvitamin D level below 50 nmol/L. Results The prevalence rate of vitamin D deficiency among children with non-haematological malignancies was 41%. There was no association between sex or diagnosis and vitamin D status. Vitamin D deficiency was more common among school children than preschool children (51% vs. 24%). Older age, season outside summer, and a more recent calendar year were significant predictors of lower 25-hydroxyvitamin D. There was a significant, albeit weak, negative correlation between 25-hydroxyvitamin D and parathyroid hormone. Conclusion Vitamin D deficiency is common among children diagnosed with cancer, particularly among school-aged children diagnosed outside summer. The prevalence appears to be increasing, underlining the need for adequate replacement of vitamin D in these patients

Demographic and disease-related factors impact bone turnover and vitamin D in children with hemato-oncological diseases

Peer reviewe

The human cathelicidin hCAP-18 in serum of children with haemato-oncological diseases

The human cathelicidin hCAP-18 (pro-LL-37) is the pro-protein of the antimicrobial peptide LL-37. hCAP-18 can be produced by many different cell types; bone marrow neutrophil precursors are the main source of hCAP-18 in the circulation. Neutrophil count is used as a marker for myelopoiesis but does not always reflect neutrophil production in the bone marrow, and thus additional markers are needed. In this study, we established the reference interval of serum hCAP-18 level in healthy children and compared serum hCAP-18 levels between different diagnostic groups of children with haemato-oncological diseases, at diagnosis. We found that children with diseases that impair myelopoiesis, such as acute leukaemia, aplastic anaemia, or myelodysplastic syndrome, presented with low hCAP-18 levels, whereas patients with non-haematological malignancies displayed serum hCAP-18 levels in the same range as healthy children. Children with chronic myeloid leukaemia presented with high circulating levels of hCAP-18, probably reflecting the high number of all differentiation stages of myeloid cells. We suggest that analysis of serum hCAP-18 provides additional information regarding myelopoiesis in children with haemato-oncological diseases, which may have future implications in assessment of myelopoiesis in clinical management