BMI change during puberty and the risk of heart failure.

AIM: Hospitalization for heart failure amongst younger men has increased. The reason for this is unknown but it coincides with the obesity epidemic. The aim of this study was to evaluate the association between childhood BMI (Body Mass Index) and BMI change during puberty for risk of adult heart failure in men. METHODS: Using the BMI Epidemiology Study (BEST), a population-based study in Gothenburg, Sweden, we collected information on childhood BMI at age 8 years and BMI change during puberty (BMI at age 20 - BMI at 8) for men born 1945-1961, followed until December 2013 (n = 37 670). BMI was collected from paediatric growth charts and mandatory military conscription tests. Information on heart failure was retrieved from high-quality national registers (342 first hospitalizations for heart failure). RESULTS: BMI change during puberty was independently of childhood BMI associated with risk of heart failure in a nonlinear J-shaped manner. Subjects in the upper quartile of BMI change during puberty (Q4) had more than twofold increased risk of heart failure compared with subjects in Q1 [HR (Hazard Ratio) = 2.29, 95% CI (Confidence Interval) 1.68-3.12]. Childhood BMI was not independently associated with risk of heart failure. Boys developing overweight during puberty (HR 3.14; 95% CI 2.25-4.38) but not boys with childhood overweight that normalized during puberty (HR 1.12, 95% CI 0.63-2.00) had increased risk of heart failure compared with boys without childhood or young adult overweight. CONCLUSION: BMI change during puberty is a novel risk factor for adult heart failure in men.

Efficacy of salpingectomy at hysterectomy to reduce the risk of epithelial ovarian cancer: a systematic review.

BACKGROUND: It has been argued that salpingectomy would reduce the risk of epithelial ovarian cancer (EOC), based on the theory of the tube being the site of origin. OBJECTIVES: To conduct a systematic review of 'salpingectomy' associated with ovarian cancer risk and 'salpingectomy with concomitant hysterectomy' on outcomes of complications including endocrine function. SEARCH STRATEGY: A comprehensive search was conducted in PubMed, Embase, and the Cochrane library. SELECTION CRITERIA: Original studies and systematic reviews were eligible. DATA COLLECTION AND ANALYSIS: Each article was quality assessed. Data were extracted and, when possible, pooled in meta-analyses. The certainty of evidence across studies was evaluated using GRADE. MAIN RESULTS: Of 844 articles found, 11 were included. No study evaluated risk reduction for EOC after salpingectomy in conjunction with hysterectomy. Two retrospective studies reported a reduced ovarian cancer risk after indicated salpingectomy, compared with no surgery: adjusted hazard ratio 0.65 (95% confidence interval, 95% CI 0.52-0.81) and adjusted odds ratio 0.58 (95% CI 0.36-0.95). Complications did not differ between groups with or without salpingectomy, but were non-systematically reported. Ovarian endocrine function, measured with surrogate outcomes, did not differ at short-term follow-up in randomised or observational studies. The certainty of evidence was very low or low for all outcomes. CONCLUSIONS: There is currently insufficient evidence to state that opportunistic salpingectomy reduces the risk of EOC. The impact on long-term endocrine function is unknown. The heterogeneity in results and identified knowledge gaps stress the need for a prospective trial. TWEETABLE ABSTRACT: Insufficient evidence for prophylactic removal of the fallopian tubes for risk reduction of ovarian cancer.

The rise and the recent decline of childhood obesity in Swedish boys: the BEST cohort.

BACKGROUND/OBJECTIVES: Childhood obesity increases the risk for adult obesity and diseases. The aim of this study was to investigate secular changes of childhood body mass index (BMI), overweight and obesity in boys born during 1946-2006, using the population-based BMI Epidemiology STudy (BEST) cohort in Gothenburg, Sweden. SUBJECTS/METHODS: We collected height and weight from archived school health records for boys born every 5 years 1946-2006 (birth cohort 1946 n=1584, each birth cohort 1951-2006 n=425). Childhood BMI at 8 years of age was obtained for all the participants. RESULTS: Childhood BMI increased 0.18 kg m-2 (95% confidence interval: 0.16-0.20) per decade increase in birth year, during 1946-2006. The increase was significant from birth year 1971, peaked 1991 and was then followed by a stabilization or tendency to a reduction. Next, we aimed to thoroughly explore the trend after birth year 1991 and therefore expanded birth cohorts 1991 (n=1566), 2001 (n=6478) and 2006 (n=6515). Importantly, decreases in mean BMI (P<0.01), prevalences of overweight (P<0.01) and obesity (P<0.05) were observed after birth year 1991. For boys born in Sweden and with parents born in Sweden, a substantial reduction in the prevalences of overweight (-28.6%, P<0.001) and obesity (-44.3%, P<0.001) were observed between birth year 1991 and birth year 2006. CONCLUSIONS: This long-term study captures both the rise and the recent decline of childhood obesity. As childhood obesity is strongly associated with subsequent adult obesity, we anticipate a similar reduction in adult obesity during the coming decades in Swedish men.

High plasma osteocalcin is associated with low blood haemoglobin in elderly men: the MrOS Sweden Study.

BACKGROUND: It has been suggested that osteoblasts are involved in the regulation of haematopoietic stem cells. Whether osteocalcin, which is derived from osteoblasts and is metabolically active, influences blood haemoglobin (Hb) levels is not known. OBJECTIVE: To determine whether plasma osteocalcin is a determinant of Hb in elderly men. METHODS: A total of 993 men (mean age 75.3 ± 3.2 years) participated in the population-based MrOS (osteoporotic fractures in men) study. Plasma osteocalcin concentration was evaluated in relation to Hb and adjustments were made for potential confounders (i.e. age, body mass index, erythropoietin, total oestradiol, fasting insulin, adiponectin, ferritin and cystatin C). RESULTS: Hb correlated (age adjusted) negatively with osteocalcin in the total study group (r = -0.12, P < 0.001) as well as in the subgroup of nondiabetic men (r = -0.16, P < 0.001). In nondiabetic men with higher osteocalcin levels, it was more likely that Hb would be in the lowest quartile (odds ratio per SD decrease in osteocalcin 1.32, 95% confidence interval 1.13-1.53). Quartiles of Hb were negatively associated (age adjusted) with osteocalcin (P < 0.001). Anaemic men (47/812) (Hb <130 g L(-1) ) had significantly higher mean osteocalcin levels than nonanaemic men (33.9 vs. 27.1 µg L(-1) , P < 0.001). In multiple stepwise linear regression analyses (adjusted for age, body mass index, total oestradiol, adiponectin, erythropoietin, fasting insulin, cystatin C, leptin, ferritin and holotranscobalamin), osteocalcin was an independent predictor of Hb concentration in nondiabetic men (P < 0.05). CONCLUSIONS: These data add further support to the evidence indicating that the bone-specific protein osteocalcin has several endocrine functions targeting the pancreas, testes, adipocytes, brain. An additional novel finding is that osteocalcin may also have a paracrine function as a regulator of haematopoiesis.

Roles of transactivating functions 1 and 2 of estrogen receptor-alpha in bone.

The bone-sparing effect of estrogen is primarily mediated via estrogen receptor-α (ERα), which stimulates target gene transcription through two activation functions (AFs), AF-1 in the N-terminal and AF-2 in the ligand binding domain. To evaluate the role of ERα AF-1 and ERα AF-2 for the effects of estrogen in bone in vivo, we analyzed mouse models lacking the entire ERα protein (ERα(-/-)), ERα AF-1 (ERαAF-1(0)), or ERα AF-2 (ERαAF-2(0)). Estradiol (E2) treatment increased the amount of both trabecular and cortical bone in ovariectomized (OVX) WT mice. Neither the trabecular nor the cortical bone responded to E2 treatment in OVX ERα(-/-) or OVX ERαAF-2(0) mice. OVX ERαAF-1(0) mice displayed a normal E2 response in cortical bone but no E2 response in trabecular bone. Although E2 treatment increased the uterine and liver weights and reduced the thymus weight in OVX WT mice, no effect was seen on these parameters in OVX ERα(-/-) or OVX ERαAF-2(0) mice. The effect of E2 in OVX ERαAF-1(0) mice was tissue-dependent, with no or weak E2 response on thymus and uterine weights but a normal response on liver weight. In conclusion, ERα AF-2 is required for the estrogenic effects on all parameters evaluated, whereas the role of ERα AF-1 is tissue-specific, with a crucial role in trabecular bone and uterus but not cortical bone. Selective ER modulators stimulating ERα with minimal activation of ERα AF-1 could retain beneficial actions in cortical bone, constituting 80% of the skeleton, while minimizing effects on reproductive organs.

Adjuvant imatinib treatment improves recurrence-free survival in patients with high-risk gastrointestinal stromal tumours (GIST).

Palliative imatinib treatment has dramatically improved survival in patients with malignant gastrointestinal stromal tumours, particularly in patients with tumours harbouring activating KIT mutations. To evaluate the effectiveness of adjuvant imatinib after radical surgery, a consecutive series of patients with high-risk tumours (n=23) was compared with historic controls (n=48) who were treated with surgery alone. The mean follow-up period was over 3 years in both groups. Only 1 out of 23 patients (4%) in the adjuvant treatment group developed recurrent disease compared to 32 out of 48 patients (67%) in the control group. This preliminary study indicates that 1 year of adjuvant treatment with imatinib dramatically improves recurrence-free survival. Confirmation of these findings awaits the results of ongoing randomised studies.

Population-based study of the diagnosis and treatment of gastrointestinal stromal tumours.

BACKGROUND: The aim of this retrospective population-based study, which was conducted before the introduction of imatinib, was to evaluate the role of surgery in patients with gastrointestinal stromal tumours (GISTs) and clarify which subgroups might benefit from adjuvant treatment. METHODS: Two hundred and fifty-nine patients with clinically detected GISTs were studied. Univariate and multivariate analyses were performed to identify predictors for recurrent disease and survival. RESULTS: Thirty of 48 patients with high-risk GISTs and all of those with overtly malignant tumours developed recurrent tumour after complete (R0) resection. Thirty-four of 38 first recurrences occurred within 36 months of surgery. No recurrence was observed after 72 months. R0 resection, achieved in 48 (80 per cent) of 60 patients with high-risk tumours, was significantly associated with a decreased risk of death from tumour recurrence (P = 0.008). CONCLUSION: Completeness of surgical resection is an independent prognostic factor in patients with high-risk GISTs. A period of adjuvant treatment with imatinib is recommended in patients with high-risk or overtly malignant GISTs who have undergone R0 resection and have a tumour-free interval of less than 6 years.

Neoadjuvant, adjuvant and palliative treatment of gastrointestinal stromal tumours (GIST) with imatinib: a centre-based study of 17 patients.

Malignant gastrointestinal stromal tumours (GIST) have a poor prognosis. Since these tumours are resistant to conventional radiation and chemotherapy, surgery has been the mainstay of treatment. However, surgery is usually inadequate for the treatment of malignant GIST. Imatinib, a KIT tyrosine kinase inhibitor, has recently been found to have a dramatic antitumour effect on GIST. In this centre-based study of 17 consecutive patients with high-risk or overtly malignant GIST, imatinib was used in three different settings - palliatively, adjuvantly, and neoadjuvantly. The treatment was found to be safe and particularly effective in tumours with activating mutations of exon 11 of the KIT gene. Clinical response to imatinib treatment correlated morphologically to tumour necrosis, hyalinisation, and reduced proliferative activity. The value of neoadjuvant imatinib treatment was illustrated in one case.

Expression and localization of Indian hedgehog (Ihh) and parathyroid hormone related protein (PTHrP) in the human growth plate during pubertal development.

Indian Hedgehog (Ihh) has been reported to control the rate of cartilage differentiation during skeletal morphogenesis in rodents through a negative feedback loop involving parathyroid hormone related protein (PTHrP). The role of Ihh and PTHrP in the regulation of human epiphyseal chondrocytes is unknown. The aim of the current study was to examine the expression and localization of Ihh and PTHrP in the human growth plate at various pubertal stages. Growth plate biopsies were obtained from patients subjected to epiphyseal surgery and the expression of Ihh and PTHrP was detected by immunohistochemistry. We show that Ihh and PTHrP are expressed mainly in early hypertrophic chondrocytes in the human growth plate. The levels of expression of Ihh and PTHrP are higher in early stages of puberty than later. Our results suggest that Ihh and PTHrP are present in the human growth plate and that Ihh and PTHrP may be involved in the regulation of pubertal growth in humans.

Ablation of TRalpha2 and a concomitant overexpression of alpha1 yields a mixed hypo- and hyperthyroid phenotype in mice.

Thyroid hormone governs a diverse repertoire of physiological functions through receptors encoded in the receptor genes alpha and beta, which each generate variant proteins. In mammals, the alpha gene generates, in addition to the normal receptor TRalpha1, a non-hormone-binding variant TRalpha2 whose exact function is unclear. Here, we present the phenotype associated with the targeted ablation of TRalpha2 expression. Selective ablation of TRalpha2 resulted in an inevitable, concomitant overexpression of TRalpha1. Both TRalpha2 +/- and -/- mice show a complex phenotype with low levels of free T3 and free T4, and have inappropriately normal levels of TSH. The thyroid glands exhibit mild morphological signs of dysfunction and respond poorly to TSH, suggesting that the genetic changes affect the ability of the gland to release thyroid hormones. However, the phenotype of the mutant mice also has features of hyperthyroidism, including decreased body weight, elevated heart rate, and a raised body temperature. Furthermore, TRalpha2-/- and TRalpha2+/- mice are obese and exhibit skeletal alterations, associated with a late-onset growth retardation. The results thus suggest that the overexpression of TRalpha1 and the concomitant decrease in TRalpha2 expression lead to a mixed hyper- and hypothyroid phenotype, dependent on the tissue studied. The phenotypes suggest that the balance of TRalpha1:TRalpha2 expressed from the TRalpha gene provides an additional level of tuning the control of growth and homeostasis in mammalian species.

GH substitution reverses the growth phenotype but not the defective ossification in thyroid hormone receptor alpha 1-/-beta-/- mice.

Thyroid hormone receptor alpha 1, beta 1 and beta 2-deficient mice (TR alpha 1-/-beta-/- mice) demonstrate growth retardation and defective ossification in the epiphyses associated with an inhibition of the GH/IGF-I axis. There are differences between TR alpha 1-/-beta-/- mice (receptor deficient) and the hypothyroid animal model (ligand deficient). Such differences include possible repressive actions exerted by unliganded receptors in the ligand-deficient (hypothyroid) model but not in the receptor-deficient model. In the present study we have investigated whether or not GH substitution rescues the skeletal phenotype of TR alpha 1-/-beta-/- mice. TR alpha 1-/-beta-/- and wild-type (WT) mice were treated with GH from day 18 until 10 weeks of age. GH substitution of mutant mice resulted in a significant and sustained stimulatory effect on the body weight that was not seen in WT mice. GH-treated mutant mice but not GH-treated WT mice demonstrated increased length and periosteal circumference of the femur. However, GH substitution did not reverse the defective ossification seen in TR alpha 1-/-beta-/- mice. TR alpha 1-/-beta-/- mice displayed increased width of the proximal tibial growth plate, which was caused by increased width of the proliferative but not the hypertrophic layer. GH substitution did not restore the disturbed morphology of the growth plate in TR alpha 1-/-beta-/- mice. In summary, GH substitution reverses the growth phenotype but not the defective ossification in TR alpha 1-/-beta-/- mice. Our data suggest that TRs are of importance both for the regulation of the GH/IGF-I axis and for direct effects on cartilage.

Cytogenetic and molecular genetic analyses of liposarcoma and its soft tissue simulators: recognition of new variants and differential diagnosis.

Liposarcoma is one of the most common sarcomas of adults. Its differential diagnosis and accurate subclassification are often problematic; the latter is also important with regard to appropriate treatment and prognosis. We studied a series of 23 liposarcomas that had unusual or previously undescribed features and 10 liposarcoma simulators and correlated the morphologic, cytogenetic, and molecular genetic findings. We found that use of cytogenetic-molecular genetic techniques aids in the distinction between myxoid-round cell liposarcoma and their simulators, chondroid lipoma, myxoid spindle cell-pleomorphic lipoma, cellular intramuscular myxoma, and myxofibrosarcoma. Poorly differentiated forms of round cell liposarcoma lacking morphologic evidence of lipogenesis can also be diagnosed using these techniques; however, the techniques do not aid in distinguishing low-grade myxoid from high-grade round cell liposarcomas. This study also shows that retroperitoneal liposarcomas with myxoid liposarcoma-like zones are part of the morphologic spectrum of well-differentiated-dedifferentiated liposarcoma rather than true myxoid liposarcomas. Perhaps most importantly, our results provide the first molecular genetic evidence that true mixed liposarcomas (mixed well-differentiated and myxoid liposarcoma) do indeed exist. They also unequivocally demonstrate the existence of small, round cell variants of pleomorphic liposarcoma that closely simulate myxoid-round cell liposarcoma.

A founder mutation of the BRCA1 gene in Western Sweden associated with a high incidence of breast and ovarian cancer.

The aim of this study was to describe and characterise a founder mutation of the BRCA1 gene in western Sweden. Of 62 families screened for BRCA mutations, 24 had BRCA1 mutations and two had BRCA2 mutations. Tumours that occurred in family members were histologically reviewed and mutational status was analysed using archival paraffin-embedded tissues. The same BRCA1 mutation, 3171ins5, was found in 16 families who were clustered along the western coast of Sweden. Mutation analysis revealed a maternal linkage in 13 families and a paternal linkage in 3. There was complete agreement between mutation analysis results obtained from blood and archival tissues. The penetrance of breast or ovarian cancer by age 70 years was estimated to be between 59 and 93%. There were no differences in survivals between breast or ovarian cancer patients with the mutation and age-matched controls. Thus, a predominant BRCA1 gene founder mutation associated with a high risk of breast and ovarian cancer has been identified and found to occur in a restricted geographical area, thereby allowing timely and cost-effective mutation screening using blood samples or archival histological material.

Fine-needle aspiration features of pilomatrixoma.

BACKGROUND: Pilomatrixoma (PMX) is a benign skin neoplasm of hair matrix origin. The fine-needle aspiration (FNA) features of PMX frequently lead to a misdiagnosis of carcinoma. METHODS: Nine cases of PMX in which a preoperative FNA was performed were reviewed. The cytologic features were compared with the histologic appearance of corresponding surgical specimens as well as with cytologic features of tumors that arose in the differential diagnosis. RESULTS: Unequivocal benign diagnoses were rendered in three cases; the correct preoperative diagnosis of PMX was rendered in two of these cases and considered in an additional case. In four additional cases, carcinoma was diagnosed or could not be excluded. A noncommittal diagnosis of epithelial tumor, most likely of skin adnexal origin, was rendered in an additional single case. Retrospective review of the FNA smears in all nine instances disclosed cytologic features that corresponded well with the histologic components of PMX. Diagnostic cytologic features included cellular aspirates; clusters of small, primitive-appearing basaloid epithelial cells; a high nuclear-cytoplasmic ratio; evenly dispersed chromatin; prominent nucleoli; pink, fibrillary material enveloping clusters of basaloid cells; multinucleated giant cells; and sheets of ghost cells. CONCLUSIONS: The FNA cytologic diagnosis of PMX may be extremely difficult; its distinction from various primary cutaneous carcinomas is most problematic. Recognition of a unique constellation of cytologic features in FNA smears in the appropriate clinical context is most helpful in making this distinction.

Fine-needle aspiration characteristics of hibernoma.

BACKGROUND: Hibernoma is a rare, benign lipomatous tumor with features of brown fat. The preoperative diagnosis of hibernoma is difficult at times because its clinical, radiographic, and fine-needle aspiration (FNA) characteristics overlap with those of liposarcoma. METHODS: The preoperative FNA findings of eight surgically excised hibernomas from seven patients (three men and four women, ages 24-60 years) were reviewed. The cytologic features were compared with the histologic features of the corresponding surgical specimens as well as lipomatous tumors and other lesions that may cause confusion in the differential diagnosis. RESULTS: The FNA cytologic features of the hibernomas were found to correspond well with their histologic appearance. The FNA findings included small, round, brown fat-like cells with uniform, small cytoplasmic vacuoles and regular, small, round nuclei; delicate branching capillaries; and variable numbers of mature fat cells. CONCLUSIONS: The FNA cytologic features of hibernoma are characteristic and useful in the preoperative investigation of lipomatous tumors, particularly with regard to excluding a diagnosis of liposarcoma.

Expression of COL1A1-PDGFB fusion transcripts in superficial adult fibrosarcoma suggests a close relationship to dermatofibrosarcoma protuberans.

The diagnosis of fibrosarcoma has become relatively rare since the recognition and definition of certain adult spindle-cell sarcomas, such as monophasic synovial sarcoma, malignant peripheral nerve sheath tumour (MPNST), and malignant fibrous histiocytoma (MFH). Although most adult fibrosarcomas occur within intra- or inter-muscular fibrous tissues, some originate from superficial soft tissues (superficially located adult fibrosarcomas) (SAFs). Recently, the COL1A1-PDGFB chimeric gene resulting from a reciprocal translocation, t(17;22), and/or a supernumerary ring chromosome, r(17;22), has been identified, not only in conventional dermatofibrosarcoma protuberans (DFSP) but also in areas of DFSP with progression to fibrosarcoma (so-called fibrosarcomatous transformation) (FS-DFSP). Since many SAFs are clinically and histologically similar to DFSP or FS-DFSP, this study postulated that the two groups may be interrelated histogenetically. To test this hypothesis, a reverse transcription-polymerase chain reaction (RT-PCR) assay was conducted to determine whether COL1A1-PDGFB fusion transcripts could be detected in six cases of SAF, using archival formalin-fixed, paraffin-embedded tissues. COL1A1-PDGFB fusion transcripts were detected in four of six SAFs, whereas no such fusion transcripts could be amplified in five deep-seated fibrosarcomas, eight congenital/infantile fibrosarcomas or 28 other spindle-cell tumours and tumour-like lesions. These results show that at least some cases of SAF are genetically similar to DFSP and FS-DFSP, suggesting that some SAFs originate from DFSP or involve similar pathogenetic mechanisms.

Prognostic factors and outcome of pelvic, sacral, and spinal chondrosarcomas: a center-based study of 69 cases.

BACKGROUND: The surgical treatment of chondrosarcoma of the pelvis, sacrum, and spine is complex and technically demanding. As such, adequate surgical margins have been difficult to achieve, resulting in poor local control and survival. The objective of this study was to assess the outcome of patients with chondrosarcomas in these sites who were treated at a tumor center by using modern, aggressive surgical techniques and to identify prognostic factors. METHODS: Sixty-nine consecutive patients with chondrosarcoma of the pelvis (46 cases), sacrum (11 cases), and mobile spine (12 cases) who were treated at Sahlgrenska University Hospital from 1967 to 1999 were included in this study. Demographic information and follow-up data were obtained and statistically analyzed. RESULTS: There were 53 men and 16 women with a mean age of 45 years and a mean tumor size of 12 cm. There were 61 conventional chondrosarcomas, Grades 1-3 (with 13 arising in a preexisting osteochondroma) and 8 Grade 4 chondrosarcomas (7 dedifferentiated and one mesenchymal). The overall local recurrence rate was 27%, and the estimated overall 5- and 10-year survival rates were 72% and 67%, respectively. In contrast, the observed local recurrence rate was 3% (1 patient) in 31 patients whose conventional chondrosarcomas were resected with adequate surgical margins; 90% of these patients survived and most of them (26 of 31 or 84%) were continuously disease free. Significant factors associated with a worse prognosis with respect to local control and/or survival were high histologic tumor grade, increasing patient age, primary surgery outside of a tumor center, incisional biopsy versus a noninvasive diagnostic procedure, and inadequate surgical margins. CONCLUSIONS: Center-based diagnosis and treatment using modern aggressive surgical techniques significantly improve the prognosis of patients with chondrosarcoma of the pelvis, sacrum, and spine.

Growth hormone receptor is expressed in human breast cancer.

Several clinical observations and experimental studies indicate that pituitary hormones, including growth hormone, play a role in the development of human breast cancer. We analyzed 48 human breast carcinomas using reverse transcription polymerase chain reaction, immunohistochemistry, and Western blotting techniques to assess growth hormone receptor expression. In 17 of these cases, adjacent normal breast tissue was similarly analyzed. These analyses revealed that growth hormone receptor (GHR) is expressed in human breast cancer and appears to be up-regulated compared to adjacent normal breast tissue. GHR expression correlated inversely with tumor grade and MIB-1 index. Progesterone receptor expression correlated positively with GHR expression. These findings, along with our observation of GHR expression in breast cancer stromal cells and previous reports of local production of growth hormone in breast carcinoma, suggest that GHR-mediated signaling pathways are involved in the development of human breast cancer, possibly via autocrine or paracrine mechanisms.

Congenital-infantile fibrosarcoma. A clinicopathologic study of 10 cases and molecular detection of the ETV6-NTRK3 fusion transcripts using paraffin-embedded tissues.

Congenital-infantile fibrosarcoma (CIFS) is a relatively indolent sarcoma that should be distinguished from more aggressive spindle cell sarcomas of childhood. CIFSs have been found to have a novel recurrent reciprocal translocation t(12;15)(p13;q25) resulting in the gene fusion ETV6-NTRK3 (ETS variant gene 6; neurotrophic tyrosine kinase receptor type 3). We studied immunohistochemical expression of NTRK3, and conducted a reverse transcription-polymerase chain reaction (RT-PCR) assay to detect the ETV6-NTRK3 fusion transcripts using archival formalin-fixed paraffin-embedded tissues from 10 CIFSs. Thirty-eight other spindle cell tumors were included as controls. The ETV6-NTRK3 fusion transcripts were identified in 7 (70%) of 10 CIFSs. Nucleotide sequence analysis showed that the fusion occurred between ETV6 exon 5 and NTRK3 exon 13. The 38 control tumors were negative for the fusion transcript. Immunohistochemically, CIFSs consistently expressed NTRK3. But the expression of NTRK3 also was observed in 22 of 38 control tumors. These results show the diagnostic usefulness of RT-PCR methods to detect ETV6-NTRK3 fusion transcripts in archival formalin-fixed paraffin-embedded tissue and the important role of NTRK3 in the development of CIFS, despite its being a protein of little importance in differential diagnosis.

A link between basic fibroblast growth factor (bFGF) and EWS/FLI-1 in Ewing's sarcoma cells.

The EWS/FLI-1 fusion gene is characteristic of most cases of Ewing's sarcoma and has been shown to be crucial for tumor transformation and cell growth. In this study we demonstrate a drastic down-regulation of the EWS/FLI-1 protein, and a growth arrest, following serum depletion of Ewing's sarcoma cells. This indicates that growth factor circuits may be involved in regulation of the fusion gene product. Of four different growth factors tested, basic fibroblast growth factor (bFGF) was found to be of particular significance. In fact, upon treatment of serum-depleted cells with bFGF, expression of the EWS/FLI-1 protein and growth of the Ewing's sarcoma cells were restored. In addition, a bFGF-neutralizing antibody, which was confirmed to inhibit FGF receptor (FGFR) phosphorylation, caused down-regulation of EWS/FLI-1. Experiments using specific cell cycle blockers (thymidine and colcemide) suggest that EWS/FLI-1 is directly linked to bFGF stimulation, and not indirectly to cell proliferation. We also demonstrated expression of FGFRs in several tumor samples of Ewing's sarcoma. Taken together, our data suggest that expression of FGFR is a common feature of Ewing's sarcoma and, in particular, that the bFGF pathway may be important for the maintenance of a malignant phenotype of Ewing's sarcoma cells through up-regulating the EWS/FLI-1 protein. Oncogene (2000) 19, 4298 - 4301