@article{SeilerEbertRudertetal.2022,
  author    = {Seiler, Jonas and Ebert, Regina and Rudert, Maximilian and Herrmann, Marietta and Leich, Ellen and Weißenberger, Manuela and Horas, Konstantin},
  title     = {Bone metastases of diverse primary origin frequently express the VDR (vitamin D receptor) and CYP24A1},
  series = {Journal of Clinical Medicine},
  volume    = {11},
  journal   = {Journal of Clinical Medicine},
  number    = {21},
  issn      = {2077-0383},
  doi       = {10.3390/jcm11216537},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-297377},
  year      = {2022},
  abstract  = {Active vitamin D (1,25(OH)2D3) is known to exert direct anti-cancer actions on various malignant tissues through binding to the vitamin D receptor (VDR). These effects have been demonstrated in breast, prostate, renal and thyroid cancers, which all have a high propensity to metastasise to bone. In addition, there is evidence that vitamin D catabolism via 24-hydroxylase (CYP24A1) is altered in tumour cells, thus, reducing local active vitamin D levels in cancer cells. The aim of this study was to assess VDR and CYP24A1 expression in various types of bone metastases by using immunohistochemistry. Overall, a high total VDR protein expression was detected in 59\% of cases (39/66). There was a non-significant trend of high-grade tumours towards the low nuclear VDR expression (p = 0.07). Notably, patients with further distant metastases had a reduced nuclear VDR expression (p = 0.03). Furthermore, a high CYP24A1 expression was detected in 59\% (39/66) of bone metastases. There was a significant positive correlation between nuclear VDR and CYP24A1 expression (p = 0.001). Collectively, the VDR and CYP24A1 were widely expressed in a multitude of bone metastases, pointing to a potential role of vitamin D signalling in cancer progression. This is of high clinical relevance, as vitamin D deficiency is frequent in patients with bone metastases.},
  language  = {en}
}
@article{EidmannEisertRudertetal.2022,
  author    = {Eidmann, Annette and Eisert, Marius and Rudert, Maximilian and Stratos, Ioannis},
  title     = {Influence of Vitamin D and C on bone marrow edema syndrome — A scoping review of the literature},
  series = {Journal of Clinical Medicine},
  volume    = {11},
  journal   = {Journal of Clinical Medicine},
  number    = {22},
  issn      = {2077-0383},
  doi       = {10.3390/jcm11226820},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-297356},
  year      = {2022},
  abstract  = {Bone marrow edema syndrome (BMES) is a rare disease with a largely unknown etiology. The aim of this scoping review is to systematically evaluate and combine the available evidence about vitamin D and C and BMES. The analysis of the manuscripts was based on country of origin, number of patients, gender, study type, epidemiology, localization, bone mineral density measurements, vitamin status and therapy. Sixty studies were included. The overall number of patients was 823 with a male-to-female ratio of 1.55:1 and a mean age of 40.9 years. Studies were very heterogeneous and of diverging scientific scope with a weak level of evidence. The hip was the most affected joint, followed by the foot and ankle and the knee; 18.3\% of patients suffered from multifocal BMES. Sixteen studies reported on vitamin D levels, resulting in a high prevalence of vitamin D deficiency (47\%) and insufficiency (17.9\%) among BMES patients. Three BME manuscripts were associated with vitamin C deficiency. Current therapeutic interventions include conservative measures (mainly unloading), various osteoactive drugs and iloprost. In summary, data about BMES in association with vitamin status is limited. A causal relationship between vitamin D or vitamin C status, osteopenia, and BMES cannot be determined from the existing literature.},
  language  = {en}
}
@article{HorasvanHerckMaieretal.2020,
  author    = {Horas, Konstantin and van Herck, Ulrike and Maier, Gerrit S. and Maus, Uwe and Harrasser, Norbert and Jakob, Franz and Weissenberger, Manuel and Arnholdt, J{\"o}rg and Holzapfel, Boris M. and Rudert, Maximilian},
  title     = {Does vitamin D deficiency predict tumour malignancy in patients with bone tumours? Data from a multi-center cohort analysis},
  series = {Journal of Bone Oncology},
  volume    = {25},
  journal   = {Journal of Bone Oncology},
  doi       = {10.1016/j.jbo.2020.100329},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230314},
  year      = {2020},
  abstract  = {Vitamin D deficiency is a global health concern that is estimated to afflict over one billion people globally. The major role of vitamin D is that of a regulator of calcium and phosphate metabolism, thus, being essential for proper bone mineralisation. Concomitantly, vitamin D is known to exert numerous extra-skeletal actions. For example, it has become evident that vitamin D has direct anti-proliferative, pro-differentiation and pro-apoptotic actions on cancer cells. Hence, vitamin D deficiency has been associated with increased cancer risk and worse prognosis in several malignancies. We have recently demonstrated that vitamin D deficiency promotes secondary cancer growth in bone. These findings were partly attributable to an increase in bone remodelling but also through direct effects of vitamin D on cancer cells. To date, very little is known about vitamin D status of patients with bone tumours in general. Thus, the objective of this study was to assess vitamin D status of patients with diverse bone tumours. Moreover, the aim was to elucidate whether or not there is an association between pre-diagnostic vitamin D status and tumour malignancy in patients with bone tumours. In a multi-center analysis, 25(OH)D, PTH and calcium levels of 225 patients that presented with various bone tumours between 2017 and 2018 were assessed. Collectively, 76\% of all patients had insufficient vitamin D levels with a total mean 25(OH)D level of 21.43 ng/ml (53.58 nmol/L). In particular, 52\% (117/225) of patients were identified as vitamin D deficient and further 24\% of patients (55/225) were vitamin D insufficient. Notably, patients diagnosed with malignant bone tumours had significantly lower 25(OH)D levels than patients diagnosed with benign bone tumours [19.3 vs. 22.75 ng/ml (48.25 vs. 56.86 nmol/L); p = 0.04). In conclusion, we found a widespread and distressing rate of vitamin D deficiency and insufficiency in patients with bone tumours. However, especially for patients with bone tumours sufficient vitamin D levels seem to be of great importance. Thus, we believe that 25(OH)D status should routinely be monitored in these patients. Collectively, there should be an increased awareness for physicians to assess and if necessary correct vitamin D status of patients with bone tumours in general or of those at great risk of developing bone tumours.},
  language  = {en}
}