Germline Mutations and Phenotypic Associations in Korean Patients With Pheochromocytoma and Paraganglioma: A Multicenter Study and Literature Review.

Genetic testing is recommended for all patients with pheochromocytomas and paragangliomas (PPGL) to establish genotype-phenotype associations. We investigated germline mutations in 59 patients with PPGL at six Korean university hospitals using next-generation sequencing (NGS) targeting 38 PPGL-associated genes, including those recommended by the Korean PPGL Task Force. Germline mutations were identified in 13 patients (22%), and affected four genes: RET, NF1, VHL, and SDHD. Germline mutations were significantly associated with a family history of PPGL, smaller tumor size, and the presence of other types of tumors. Using 95 Korean PPGL cases with germline mutations identified through a literature review and 13 cases from our cohort, we characterized genotype-phenotype correlations. Mutation hotspots were identified in specific codons of RET (codons 631 and 634), VHL (157 and 167), and SDHB (131 and 253). NF1 mutations varied, indicating the absence of common hotspots. These findings highlight the efficacy of the recommended NGS panel for Korean patients with PPGL and the importance of genetic testing in establishing clinical management and personalized therapeutic strategies.

USP37 Deubiquitinates CDC73 in HPT-JT Syndrome.

The CDC73/HRPT2 gene, a defect which causes hyperparathyroidism-jaw tumor (HPT-JT) syndrome, encodes CDC73/parafibromin. We aimed to investigate whether CDC73 would be a target for ubiquitin-proteasome degradation. We cloned full-length cDNAs encoding a family of 58 ubiquitin-specific deubiquitinating enzymes (DUBs), also known as ubiquitin-specific proteases (USPs). Use of the yeast two-hybrid system then enabled us to identify USP37 as interacting with CDC73. The biochemical interaction between the USP37 and CDC73 and their reciprocal binding domains were studied. Co-localization of CDC73 and USP37 was observed in cells. CDC73 was found to be polyubiquitinated, and polyubiquitination of CDC73 was prominent in mutants. CDC73 was deubiquitinated via K48-specific ubiquitin chains by USP37, but not by the catalytically inactive USP37C350S mutant. Observation of the binding between deletion mutants of CDC73 and USP37 revealed that the ß-catenin binding site of CDC73 and the ubiquitin-interacting motifs 2 and 3 (UIM2 and 3) of USP37 were responsible for the interaction between the two proteins. Moreover, these two enzymes co-existed within the nucleus of COS7 cells. We conclude that USP37 is a DUB for CDC73 and that the two proteins interact through specific domains, suggesting that USP37 is responsible for the stability of CDC73 in HPT-JT syndrome.

Clinical features and signaling effects of RET D631Y variant multiple endocrine neoplasia type 2 (MEN2).

BACKGROUND/AIMS: Germline mutations of the rearranged during transfection (RET) gene cause multiple endocrine neoplasia type 2 (MEN2). About 85% of RET mutations in MEN2 occur in codon Cys634. The RET D631Y mutation has recently been discovered, and we have studied its molecular expression and clinical consequences. METHODS: We analyzed the clinical characteristics of a total of 34 D631Y variant MEN2 individuals from seven families. We also constructed wild-type and mutant C630Y, D631Y, and C634R/W expression vectors and investigated their effects on signaling pathways and ability to correct the phenotypes of RET mutant cells. RESULTS: The median ages at diagnosis of pheochromocytoma and medullary thyroid carcinoma (MTC) were higher in patients with RET D631Y variant MEN2 than in those with the C634R/W variant (49:53.5 years vs. 33.5:27 years, respectively), and the penetration of the D631Y mutation with respect to MTC was lower than that of the C634R/W mutation (32.3% vs. 90%). The effects of the mutant vectors on phosphorylation of RET signaling molecules and focus formation were significantly different from those of wild type, but there were no significant differences between the mutants. D631Y scored significantly higher for chemotaxis and wound healing than C630Y, but lower than C634R and C634W. CONCLUSION: We suggest that the tumorigenic potential conferred by the D631Y mutation is lower than that conferred by the C634R/W mutation, but higher than that conferred by C630Y. Thus, the risk level of the RET D631Y variant appears to be higher than that of C630Y and lower than that of C634R/W.

Association of serum calcium concentrations with fibrinogen and homocysteine in nondiabetic Korean subjects.

Considerable evidence shows that increased serum calcium levels are associated with metabolic disorders, cardiovascular disease, and increased mortality. This study investigated whether serum calcium, within a normal range, is significantly associated with serum fibrinogen and homocysteine, markers of increased cardiovascular disease risk in nondiabetic Korean subjects.A cross-sectional analysis was performed on 1096 subjects (mean age, 55.1 ±â€Š11.1 years; 36.1% women) undergoing a general health checkup. Serum biochemistry was analyzed including serum albumin-corrected calcium (Cac), insulin resistance (IR, using homeostasis model assessment [HOMA]), fibrinogen, and homocysteine.Compared with patients within the lowest Cac quartile, those with higher Cac levels had increased fibrinogen and homocysteine levels as well as an increased proportion of smoking, dyslipidemia, and HOMA-IR. Correlation analyses revealed linear relationships for Cac with fibrinogen and homocysteine in both genders. After adjustment for confounding factors, serum Cac was significantly associated with high fibrinogen (odds ratio [OR] for the highest vs the lowest quartile = 1.76, 95% confidence interval [CI] = 1.09-2.83, P = 0.02) and homocysteine (OR = 1.83, 95% CI = 1.07-3.11, P = 0.027). Multivariate regression models showed that Cac was linearly associated with fibrinogen (standardized ß = 0.14, P < 0.001) and homocysteine (standardized ß = 0.07, P = 0.009).High normal calcium concentrations were independently associated with increased levels of fibrinogen and homocysteine. Further investigation is needed to validate whether slightly increased calcium levels within the normal range indicate a higher risk of cardiovascular disease.

Association between serum calcium and phosphorus concentrations with non-alcoholic fatty liver disease in Korean population.

BACKGROUND AND AIM: Growing evidence suggests that non-alcoholic fatty liver disease (NAFLD) is interrelated with renal dysfunction and disturbed bone metabolism, both of which play a key role in calcium and phosphorus homeostasis. We investigated the association between NAFLD and serum calcium and phosphorus levels in Korean subjects. METHODS: We performed a cross-sectional analysis of 16,592 subjects undergoing a general health checkup. NAFLD was assessed based on ultrasonographically detected fatty liver in the absence of excessive alcohol consumption and other causes of liver disease. RESULTS: The proportion of the population with fatty liver detected by ultrasonography was 43.2% for males and 17.6% for females. We observed that a higher serum albumin-corrected calcium (Ca(c)) level was associated with smoking, hypertension, and unfavorable metabolic parameters in both genders, but the serum phosphorus levels showed an inconsistent correlation with metabolic abnormalities. After adjusting for age, gender, waist circumference, body mass index, smoking status, exercise, diabetes, hypertension, lipid profiles, and renal function, serum Cac , phosphorus, and Cac -phosphorus products were independent risk factors for fatty liver (odds ratio [OR]: 1.71, 95% confidence interval [CI]: 1.49-1.95, P < 0.001; OR: 1.34, 95% CI: 1.22-1.48, P < 0.001; and OR: 1.20, 95% CI: 1.14-1.26, P < 0.001, respectively), and the risk of fatty liver increased in a graded manner over the quartiles. CONCLUSION: Serum calcium and phosphorus levels are significantly associated with NAFLD. Further investigation is needed to verify whether calcium and phosphorus levels indicate a higher risk of NAFLD.

Upregulation of FGFR1 expression is associated with parathyroid carcinogenesis in HPT-JT syndrome due to an HRPT2 splicing mutation.

Mutations of the HRPT2 gene, which are responsible for hyperparathyroidism-jaw tumor (HPT-JT) syndrome, have been implicated in the development of a high proportion of parathyroid carcinomas. The aim of this study was to investigate differences in expression of the most important genes connected with parathyroid carcinoma between HPT-JT syndrome due to an HRPT2 splicing mutation, normal parathyroid tissue and sporadic parathyroid adenoma. Total RNAs were extracted from parathyroid carcinoma in HPT-JT syndrome harbouring HRPT2 splicing mutation or sporadic parathyroid adenoma and normal parathyroid gland, and subjected to Illumina DASL-based gene expression assay. Unsupervised hierarchical clustering analysis was used to compare gene expression in HPT-JT syndrome, sporadic parathyroid adenoma and normal parathyroid glands. We identified differentially regulated genes in HPT-JT syndrome and sporadic parathyroid adenoma relative to normal parathyroid glands using a combination of Welch's t-test and fold-change analysis. Quantitative PCR, RT-PCR and IHC were used for validation. Sixteen genes differentially regulated in the parathyroid carcinoma were associated with signal pathways, MAPK, regulation of actin cytoskeleton, prostate cancer and apoptosis. FGFR1 expression was confirmed to be significantly upregulated by validation experiments. Our gene expression profiling experiments suggest that upregulated FGFR1 expression appears to be associated with parathyroid carcinoma in HPT-JT syndrome due to an HRPT2 splicing mutation.

Novel germline SDHD mutation in a patient with recurrent familial carotid body tumor and concomitant pheochromocytoma.

BACKGROUND: Recent advances in genetics revealed that 25% to 30% of head and neck paragangliomas (PGLs) are inherited tumors associated with germline mutation, mainly in the succinate dehydrogenase (SDH) gene. METHODS: DNA was isolated from whole blood and polymerase chain reaction (PCR) products were sequenced with an ABI3730 × 1 Genetic Analyzer. RESULTS: A 30-year-old Korean woman underwent resection of a carotid PGL. Fourteen years later, she was readmitted for a cervical mass. (18) F-fluorodeoxyglucose (FDG)-positron emission tomography (PET)/CT revealed a hot spot in the adrenal gland, besides the carotid mass. Surgical pathology confirmed recurrence of the carotid PGL and a concomitant pheochromocytoma. Genetic analysis revealed SDHD c.119del T (p.I40TfsX46) mutation. One daughter has been identified as a carrier. CONCLUSION: We found a novel SDHD mutation from a Korean family that shows similar clinical features to those in other SDHD mutations, mostly from Western countries. Further studies are needed to determine whether similar genotype-phenotype correlations exist in the Asian patients with familial PGLs.

A case of Dyke-Davidoff-Masson syndrome associated with central hypothyroidism and secondary adrenal insufficiency.

A diagnosis of central hypothyroidism (CH) can be missed easily or delayed without a high index of suspicion due to normal or slightly altered thyroid stimulating hormone (TSH) levels during the initial screening test for thyroid dysfunction. A correct diagnosis of CH is very important for safely treating patients. Specifically, doctors must ensure a proper evaluation of combined adrenal insufficiency to prevent a fatal adrenal crisis. Here we report a case of CH combined with secondary adrenal insufficiency in a 42-year-old woman with Dyke-Davidoff-Masson syndrome, which is a rare neurological disease.

Association between low serum free thyroxine concentrations and coronary artery calcification in healthy euthyroid subjects.

BACKGROUND: Considerable evidence suggests that hypothyroidism could promote atherosclerotic vascular changes. We planned this study to investigate whether serum free thyroxine (FT4) or thyroid-stimulating hormone (TSH) levels are associated with coronary artery calcification measured in healthy euthyroid subjects. METHODS: A cross-sectional analysis was performed among subjects who visited our hospital for a health checkup. Among 1849 subjects, 669 (mean age 55.3±8.8 years; 392 men) with FT4 and TSH in the normal ranges were included after excluding those with diabetes, a history of current smoking and cardiovascular disease (CVD), or the use of drugs for hypertension, antithyroid drugs, or thyroid hormone preparations. Coronary artery calcium scores (CACS) were measured by multi-detector computed tomography. RESULTS: Subjects with a CACS >100 had lower FT4 levels than those with a lower CACS (p=0.017), whereas no difference was observed in the TSH levels among CACS categories. FT4 levels had an odds ratio of 0.06 for high CACS (95% confidence interval=0.01-0.74; p=0.028) after the adjustment for CVD risk factors. In multivariate regression analysis, CACS was negatively correlated with FT4 levels (ß=-0.823, p=0.032), and the inverse association between FT4 and CACS remained significant only in men (p=0.011). CONCLUSION: FT4 levels were inversely associated with coronary artery calcification in euthyroid healthy subjects, especially in men independent of conventional CVD risk factors. Further studies are needed to validate whether subjects with decreased FT4 levels within the normal reference range are at a high CVD risk and have poor cardiovascular outcomes.

Analysis of a novel AVPR2 mutation in a family with nephrogenic diabetes insipidus.

Congenital nephrogenic diabetes insipidus (NDI) is a rare X-linked recessive disorder associated with germ-line mutations of the arginine vasopressin (AVP) receptor type 2 (AVPR2) gene. Recent molecular studies have demonstrated that insensitivity of renal tubule cells to AVP is associated with AVPR2 mutations. We identified a novel deletion mutation at nucleotide position 302 (302delC), in a Korean NDI family, that results in a frameshift and a truncated receptor protein. To identify the mutant AVPR2 protein we developed an expression vector for the AVPR2 mutation by a PCR-based restriction fragment replacement strategy. COS-7 cells were transiently transfected with expression vectors for the wild-type and mutant genes, and we analyzed AVP-induced cyclic adenosine monophos-phate (cAMP) responses, and assessed the localization of AVPR2 receptors, in the transfected COS-7 cells. In the cells expressing the mutant gene, the maximum AVP-induced cAMP response was reduced and the truncated receptor proteins were retained within the cytoplasmic compartment. These results suggest that the novel frameshift AVPR2 (302delC) mutation is responsible for the AVP resistance in the family with congenital NDI.

Association of oxidative stress with postmenopausal osteoporosis and the effects of hydrogen peroxide on osteoclast formation in human bone marrow cell cultures.

It has been suggested that oxidative stress is associated with the pathogenesis of osteoporosis. The objective of this study was to explore the association between a marker of oxidative stress and either bone turnover markers or bone mineral density (BMD) in postmenopausal women. In addition, the effects of oxidative stress on the formation of osteoclasts in human bone marrow cell culture were examined. We performed a cross-sectional analysis in healthy postmenopausal women aged 60-78 years (n = 135, 68.2 +/- 4.9). Oxidative stress was evaluated in the serum by measuring 8-hydroxy-2'-deoxyguanosine (8-OH-dG) levels. The biochemical markers of bone turnover and areal BMD were measured in all participants. Multivariate linear regression analysis revealed a negative association between 8-OH-dG levels and BMD of the lumbar spine, total hip, femoral neck, and trochanter and positive association with type I collagen C-telopeptide (ICTP) levels. The odds ratio of 8-OH-dG for osteoporosis was 1.54 (1.14-2.31, P = 0.003). In cultures of primary human marrow cells, H2O2 caused concentration-dependent activation of TRAP-positive multinucleated giant cells. H2O2 also increased the area of pits per osteoclast activity assay substrate. RT-PCR showed that H2O2 stimulated the expression of M-CSF and RANKL and increased the RANKL/OPG ratio. The data support the view that oxidative stress is associated with increased bone resorption and low bone mass in otherwise healthy women. In addition, RANKL and M-CSF stimulation induced by oxidative stress may participate in osteoclastogenesis in human bone.

Analysis of aberrantly spliced HRPT2 transcripts and the resulting proteins in HPT-JT syndrome.

The risk for parathyroid carcinoma is high in those with the HPT-JT syndrome. Parafibromin is a protein derived from HRPT2 gene and its inactivation has been coupled to familial form of parathyroid malignancy. We previously identified altered transcripts resulting from splice site mutation of the HRPT2 gene in a family with this syndrome. In the present work, we investigated the stability of the altered HRPT2 transcripts and translation products produced in the HPT-JT syndrome. We quantified the differentially expressed HRPT2 mRNAs using real-time RT-PCR and developed a novel monoclonal parafibromin antibody to study the expression of parafibromin in the HPT-JT syndrome. The relative quantification ratios of the wild type HRPT2 mRNA, 23 bp deleted HRPT2 mRNA, and 70 bp deleted HRPT2 mRNA in the HPT-JT syndrome were 0.68, 0.17 and 0.15, respectively. But endogenous parafibromin expression was not detectable in the HPT-JT syndrome carcinoma. The altered HRPT2 mRNAs resulting from the splice site mutation in the HPT-JT syndrome were stable, but their parafibromin translation products from the HPT-JT syndrome carcinoma were probably degraded rapidly. Additional studies that aim to fully characterize the consequences of altered HRPT2 mRNAs in HPT-JT syndrome are required to explore these possibilities.

Short-term changes in bone and mineral metabolism following gastrectomy in gastric cancer patients.

Changes in bone and mineral metabolism that occur after gastrectomy have long been recognized. Gastrectomy has been identified as a risk factor for decreased bone mass and the increased fracture incidence. Previous investigations concerning postgastrectomy bone disease have been observational studies. No prospective studies have been reported that quantify the amount of bone loss after gastrectomy within the same patients. This study investigated 46 patients undergoing gastrectomy for gastric adenocarcinoma and analyzed 36 patients (58.1+/-10.8 years, 24 men and 12 women) who had dual energy X-ray absorptiometry (DXA) performed before and 1 year after gastrectomy. Systemic adjuvant chemotherapy was administered to 14 patients. Blood was sampled from all patients to determine serum calcium, phosphorous, and bone turnover marker levels before gastrectomy and at 1, 3, 6 and 12 months after surgery and for serum parathyroid hormone (PTH) and 25-hydroxyvitamin D levels before and 12 months after surgery. The mean bone loss in the lumbar spine, total hip, femoral neck, and trochanter, which was calculated as the percentage change from the baseline to the level measured at 12 months, was 5.7% (P<0.01), 5.4% (P<0.01), 6.6% (P<0.01) and 8.7% (P<0.01), respectively. Bone loss was generally greater in the group receiving chemotherapy. The serum calcium and phosphorous levels were not changed significantly and remained within the normal range throughout the observation period. After gastrectomy, the level of ICTP increased and reached a peak at 1 and 3 months, and progressively declined to baseline by 12 months. The osteocalcin levels were not coupled to an increase before 6 months. The level of 25-hydroxyvitamin D at 12 months postgastrectomy was not significantly changed compared to the baseline, however, the PTH levels increased by a mean of 63.6% at 12 months compared to the baseline (P<0.01). Significant correlations were found between the percent change in the BMD at the lumbar spine and total hip and the percentage change for the PTH level from their baselines to 12 months. The changes in the BMD at total hip, femoral neck, and trochanter also correlated to the change in body weight at 12 months. The data obtained by this study provides evidence that profound bone loss occurs in the setting of a bone remodeling imbalance during the early postgastrectomy period and allows the speculation that the gastrectomy related bone loss may be partially due to an overproduction of PTH.

Changes in the serum sex steroids, IL-7 and RANKL-OPG system after bone marrow transplantation: influences on bone and mineral metabolism.

This study prospectively investigated the changes of the serum levels of the sex steroids, IL-7, soluble receptor activator of nuclear factor kappaB ligand (sRANKL) and osteoprotegerin (OPG) in bone marrow transplantation (BMT) recipients. This study also examined whether the changes of these cytokine levels and sex steroids actually influence bone turnover and post-BMT bone loss by correlation analysis. Data were analyzed from 39 patients (33.6+/-6.4 years, 19 men and 20 women) who had DXA performed before BMT and at 1 year after BMT. The bone turnover markers, sex steroids and the cytokine levels were measured before BMT and serially after BMT. The mean bone loss in the lumbar spine and the total proximal femur was 5.9% (P < 0.01) and 11.3% (P < 0.01), respectively. During the immediate post-BMT period, bone formation decreased, whereas the bone resorption increased. For the female recipients, the estradiol levels declined at 1 week after BMT, and they did not recover to the basal levels. For the male recipients, the testosterone levels decreased at 1 week and then it increased to its baseline level. The IL-7 levels reached their maximum at 1 week and then declined to baseline level by 3 months. The serum sRANKL, OPG levels and the sRANKL/OPG ratio showed their peak at post-BMT 3 weeks. The mean daily dose of steroid was associated with suppressed bone formation, enhanced bone resorption and increased sRANKL levels. The IL-7 levels were also noted to be either positively correlated with the levels of ICTP or they were negatively correlated with the levels of osteocalcin at 1 and 3 weeks after BMT. Bone loss at the lumbar spine and the proximal femur was influenced by the decreased sex steroids and increased IL-7 levels. During the observation period, the IL-7 levels showed positive correlations with the sRANKL levels and the sRANKL/OPG ratio. For the female patients, the serum IL-7 levels were negatively associated with the estradiol levels at 1 and 3 weeks after BMT. All these findings suggest that IL-7 plays an important role for post-BMT bone loss, and this possibly happens via the RANKL pathway. These data also suggest that the up-regulation of IL-7 during the early post-BMT period may result from a deficiency of estrogen.

The effect of simvastatin on the proliferation and differentiation of human bone marrow stromal cells.

Statins have been postulated to affect the bone metabolism. Recent experimental and epidemiologic studies have suggested that statins may also have bone protective effects. This study assessed the effects of simvastatin on the proliferation and differentiation of human bone marrow stromal cells (BMSCs) in an ex vivo culture. The bone marrow was obtained from healthy donors. Mononuclear cells were isolated and cultured to osteoblastic lineage. In the primary culture, 10(-6) M simvastatin diminished the mean size of the colony forming units-fibroblastic (CFU-Fs) and enhanced matrix calcification. At near confluence, the cells were sub-cultured. Thereafter, the alkaline phosphatase (ALP) activities of each group were measured by the time course of the secondary culture. Simvastatin increased the ALP activity in a dose dependent manner, and this stimulatory effect was more evident during the early period of culture. A 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay was performed during the secondary culture in order to estimate the effect of simvastatin on the proliferation of human BMSCs. When compared to the control group, simvastatin significantly decreased the proliferation of cells of each culture well. 10(-6) M of simvastatin also significantly enhanced the osteocalcin mRNA expression level. This study shows that simvastatin has a stimulatory effect on bone formation through osteoblastic differentiation, and has an inhibitory effect on the proliferative potential of human BMSCs.

A Novel IVS2-1G>A mutation causes aberrant splicing of the HRPT2 gene in a family with hyperparathyroidism-jaw tumor syndrome.

HRPT2, the gene associated with hyperparathyroidism-jaw tumor (HPT-JT) syndrome, was previously mapped to 1q24-q32. It was recently cloned, and several germline mutations were found to predispose to HPT-JT syndrome. We sequenced the complete HRPT2 coding sequence and splice-junctional regions in a Korean family with HPT-JT syndrome and identified a novel germline mutation, IVS2-1G>A in intron 2, that caused the autosomal dominant trait of HPT-JT syndrome in this family. RT-PCR and sequencing of the transcripts revealed that this splicing mutation generated alternative splicing errors leading to the formation of two different transcripts, one with exon 3 deleted, the other lacking the first 23 bp of exon 3 due to the use of an internal splice acceptor in exon 3. Translation of both transcripts results in premature termination. In addition, we detected two novel somatic mutations of HRPT2 in malignant parathyroid tumors from the affected individuals. One, 85delG, causes premature termination; the other, an 18 bp in-frame deletion of 13_30delCTTAGCGTCCTGCGACAG, suggests that this region may be important in the development of the parathyroid carcinomas in HPT-JT syndrome. These findings provide further evidence that mutation of HRPT2 is associated with the formation of parathyroid tumors in HPT-JT syndrome.

Changes in the serum growth factors and osteoprotegerin after bone marrow transplantation: impact on bone and mineral metabolism.

The loss of bone mass often occurs after bone marrow transplantation (BMT), particularly during the early posttransplant period. There are few reports on the role of growth factors and osteoprotegerin (OPG) in the post-BMT bone loss. This study prospectively investigated 110 patients undergoing BMT and analyzed 36 patients who had dual-energy x-ray absorptiometry performed before BMT and 1 yr after BMT. The biochemical markers of bone formation and resorption were measured at the short-term intervals during the year-long follow-up. The serum IGF-I, IGF binding protein (IGFBP)-3, fibroblast growth factor-2, macrophage-colony stimulating factor (M-CSF), and OPG levels were measured before and 1 wk, 3 wk, and 3 months after BMT. The mean bone loss in the lumbar spine and the total proximal femur, which was calculated as the percent change from the baseline to the level at 1 yr, was 5.2% (P < 0.05) and 11.6% (P < 0.01), respectively. During the immediate post-BMT period, bone formation decreased, whereas bone resorption increased, which was indicated by the biochemical markers of bone turnover. The serum IGF-I levels also decreased progressively until 3 wk and then increased to the basal values at 3 months. The serum IGFBP-3 levels decreased progressively until 3 months. The serum fibroblast growth factor-2 levels decreased to the nadir at 1 wk and gradually recovered to the basal values at 3 months. The serum M-CSF levels increased immediately after BMT, which declined to its baseline level by 3 months. The serum OPG levels increased progressively, reached a peak at 3 weeks, and declined thereafter. There were significant correlations between the IGF-I and osteocalcin levels before BMT and at 3 wk after BMT (r = 0.45, P < 0.01; r = 0.54, P < 0.01). During the observation period, the serum IGFBP-3 and M-CSF levels showed positive correlations with the osteocalcin and serum collagen I carboxyl-terminal telopeptide levels, respectively. Although statistically not significant, the OPG levels tended to be positively associated with the serum collagen I carboxyl-terminal telopeptide levels. Significant correlations were observed between the percent changes from the baseline to 1 yr in the bone mineral density at the proximal femur and the serum IGF-I levels at 3 wk and 3 months after BMT (r = 0.52, P < 0.01; r = 0.41, P < 0.05).