TGF-ß signaling promotes desmoid tumor formation via CSRP2 upregulation.

Desmoid tumors (DTs), also called desmoid-type fibromatoses, are locally aggressive tumors of mesenchymal origin. In the present study, we developed a novel mouse model of DTs by inducing a local mutation in the Ctnnb1 gene, encoding ß-catenin in PDGFRA-positive stromal cells, by subcutaneous injection of 4-hydroxy-tamoxifen. Tumors in this model resembled histologically clinical samples from DT patients and showed strong phosphorylation of nuclear SMAD2. Knockout of SMAD4 in the model significantly suppressed tumor growth. Proteomic analysis revealed that SMAD4 knockout reduced the level of Cysteine-and-Glycine-Rich Protein 2 (CSRP2) in DTs, and treatment of DT-derived cells with a TGF-ß receptor inhibitor reduced CSRP2 RNA levels. Knockdown of CSRP2 in DT cells significantly suppressed their proliferation. These results indicate that the TGF-ß/CSRP2 axis is a potential therapeutic target for DTs downstream of TGF-ß signaling.

Financial burden of surgical treatment for retroperitoneal sarcoma.

PURPOSES: The purpose of this study was to compare the financial burden of surgery for retroperitoneal sarcoma (RPS) and gastric cancer (GC). METHODS: All patients who underwent surgery for GC or RPS between 2020 and 2021 at Nagoya University Hospital were included. The clinical characteristics, surgical fees per surgeon, and surgical fees per hour were compared between the two groups. RESULTS: The GC and RPS groups included 35 and 63 patients, respectively. In the latter group, 37 patients (59%) underwent tumor resection combined with organ resection; the most common organ was the intestine (n = 23, 37%), followed by the kidney (n = 16, 25%). The mean operative time (248 vs. 417 min, p < 0.001) and intraoperative blood loss (423 vs. 1123 ml, p < 0.001) were significantly greater in the RPS group than in the GC group. The mean surgical fee per surgeon was USD 1667 in the GC group and USD 1022 in the RPS group (p < 0.001) and USD 1388 and USD 777 per hour, respectively (p < 0.001). CONCLUSIONS: The financial burden of surgical treatment for RPS is unexpectedly higher than that for GC.

Development of Therapeutic Agent for Osteoarthritis via Inhibition of KIAA1199 Activity: Effect of Ipriflavone In Vivo.

This study aimed to clarify the effects of ipriflavone, which effectively reduces KIAA1199 activity, on osteoarthritis (OA) development and progression in an in vivo OA mouse model. The OA model mice were divided into the ipriflavone (200 mg/kg/day) group and the control group. OA onset and progression were evaluated with the Mankin score, and KIAA1199 expression and hyaluronan (HA) accumulation were analyzed by immunostaining. The molecular weight of HA in the cartilage tissue and serum HA concentration were analyzed by chromatography and competitive HA enzyme-linked immunoassay. The effects of ipriflavone on the bovine cartilage explant culture under the influence of IL-1ß were also investigated. In the ipriflavone group, Safranin-O stainability was well-preserved, resulting in significant reduction of the Mankin score (p = 0.027). KIAA1199 staining positivity decreased and HA stainability was preserved in the ipriflavone group. The serum HA concentration decreased, and the molecular weight of HA in the cartilage tissue increased in the ipriflavone group. The results of the cartilage explant culture indicated that ipriflavone could reduce GAG losses and increase the molecular weight of HA. Thus, ipriflavone may have an inhibitory effect on OA development/progression. Ipriflavone could be a therapeutic drug for OA by targeting KIAA1199 activity.

Limitations and benefits of FDG-PET/CT in NF1 patients with nerve sheath tumors: A cross-sectional/longitudinal study.

The purposes of this study were to re-confirm the usefulness of PET/CT in the differentiation of benignity/malignancy of neurogenic tumors in NF1 patients, and to analyze the natural course of plexiform neurofibroma (pNF) and clarify whether PET/CT is also useful for detecting tumors other than neurogenic tumors. PET/CT was prospectively imaged in 36 NF1 patients. There were 14 malignant peripheral nerve sheath tumors (MPNSTs) in 14 patients, and 54 pNFs in 30 patients. Nine patients had both MPNST and pNF. Maximal standardized uptake value (SUVmax) was significantly higher in MPNST (median 7.6: range 4.1-10.4) (P < .001) compared with that of pNF (median 3.7: range 1.6-9.3). The cut-off value of 5.8 resulted in a sensitivity of 78.6% and specificity of 88.9%. Median age was 29 y, and median maximum tumor diameter was 82 mm in 14 MPNST patients. The 5-y overall survival rate was 46.8%. Three patients with low-grade MPNST were alive without disease at the time of this report. In 9 patients in which pNF and MPNST co-existed, 2 showed a higher SUVmax of pNF than that of MPNST. Natural history analysis of pNF (n = 43) revealed that no factors significantly correlated with increased tumor size. Nine lesions other than neurogenic tumors were detected by PET/CT including 5 thyroid lesions and 3 malignant neoplasms. This study revealed the usefulness and limitation of PET/CT for NF1 patients. In the future, it will be necessary to study how to detect over time the malignant transformation of pNF to MPNST, via an intermediate tumor.

Trends in diagnostic and therapeutic strategies for extra-abdominal desmoid-type fibromatosis: Japanese musculoskeletal oncology group questionnaire survey.

OBJECTIVE: The mainstay of treatment modality for extra-abdominal desmoid-type fibromatosis (DF) has shifted from surgery, which often impairs ADL/QOL, to conservative treatment including active surveillance. In the present study, we conducted a longitudinal survey on the diagnosis and treatment of DF at facilities belonging to the Japanese Musculoskeletal Oncology Group, which is a research group of facilities specializing in the treatment of bone and soft tissue tumors in Japan to clarify the transition of medical care for extra-abdominal DF. METHODS: The same questionnaire was administered in 2015 and 2018, and responses were obtained from 46 (69%) of 67 facilities and 42 (53%) of 80 facilities in 2015 and 2018, respectively. RESULTS: Although immunostaining for ß-catenin was often used for the pathological diagnosis in both 2015 and 2018, CTNNB1 mutation analysis was not performed either in 2015 or in 2018. As for the treatment strategy for resectable cases, surgical treatment including wide resection was selected at 11 facilities (24% of respondents) in 2015, and further decreased to 5 facilities (12%) in 2018. Conservative treatment with active surveillance or medical treatment was the most common treatment for both resectable and difficult-to-resect cases. COX-2 inhibitors and tranilast were often used in the drug treatment of both resectable and difficult-to-resect cases. Few facilities provided radiotherapy, methotrexate and vinblastine, or DOX-based chemotherapy for refractory cases in both 2015 and 2018. CONCLUSIONS: A good trend was found in the questionnaire survey. It will be further necessary to disseminate clinical practice guidelines to physicians more widely, and to have them understand and implement the most up-to-date medical practice strategies for this rare disease.

Desmoid with biweekly methotrexate and vinblastine shows similar effects to weekly administration: A phase II clinical trial.

Low-dose methotrexate (MTX) plus vinblastine (VBL) chemotherapy is an effective treatment for desmoid-type fibromatosis (DF). However, previous reports have described a weekly regimen, with no reports available on a biweekly one. The aim of this study was to determine the clinical outcomes of a biweekly regimen in a cohort prospectively treated in our single institution. Since 2010, we have prospectively treated refractory DF patients with biweekly MTX (30 mg/m2 ) + VBL (6 mg/m2 ). Efficacy, progression-free survival (PFS), and correlating factors were analyzed. Adverse events (AEs) were recorded. In total, 38 patients received low-dose MTX + VBL therapy, and its efficacy was assessed in 37 of them. Nineteen (51%) patients showed partial response (PR). Clinical benefit rate was 95%. PFS at 5 y was 80.8%. In PR cases, median time to response was 10 mo. Longer duration of therapy was significantly associated with the response of PR (P = .007) by univariate analysis. There was no clear association between various clinicopathological factors, including tumor size, location, catenin beta-1 (CTNNB1) mutation status with effect. Only 3 AEs of grade 3/4 were observed. Tumor regrowth after MTX + VBL discontinuation was observed in 5 (20%) of 25 patients. Biweekly administration of MTX + VBL chemotherapy was well tolerated compared with weekly administration, and its efficacy was anticipated in DF patents, although the time needed to achieve a response may be relatively long. The treatment interval should be determined taking into account both the condition of the tumor and the patient's preference.

Risk factors of local recurrence after surgery in extraabdominal desmoid-type fibromatosis: A multicenter study in Japan.

This study was undertaken to clarify the risk factors, including the mutation status of CTNNB1, for the local recurrence after surgery of the rare disease desmoid-type fibromatosis. It was designed as a multiinstitutional joint research project with 7 major centers in Japan participating. The committee members of 7 major medical centers specializing in bone and soft tissue tumors formed this study group to develop clinical care guidelines. Of 196 cases with specimens and medical records collected from the 7 institutions, 88 surgically treated ones were analyzed regarding clinicopathologic prognostic factors including CTNNB1 mutation status. Excluding R2 cases (n = 3), 5-year local recurrence-free survival (LRFS) was 52.9%. No case had received pre- or postoperative radiotherapy. Univariate analysis revealed that extremity location (P < .001) and larger size (8 cm or more, P = .036) were significant adverse risk factors for LRFS. Multivariate analysis indicated that extremity location (P < .001) was a significantly adverse factor in addition to recurrent tumor (P = .041), S45F mutation (P = .028), and R1 surgical margin (P = .039). Preoperative drug treatment, including nonsteroidal antiinflammatory drugs, did not reduce the incidence of local recurrence (P = .199). This is the first study to analyze the factors correlating with outcomes of surgical treatment, including CTNNB1 mutation status, in a relatively large number of cases from an Asian country. Tumor location was found to be the most influential prognostic factor for local recurrence, similar to the results from Europe and North America. The development of more sensitive method(s) for determination of CTNNB1 mutation is a priority for future study.

Efficacy of low-dose chemotherapy with methotrexate and vinblastine for patients with extra-abdominal desmoid-type fibromatosis: a systematic review.

OBJECTIVE: The treatment modality for desmoid-type fibromatosis has shifted from surgery to conservative treatment. This systematic review aims to evaluate the efficacy of low-dose chemotherapy with methotrexate and vinblastine for patients with extra-abdominal desmoid-type fibromatosis. METHODS: We searched the pertinent literature from January 1990 to August 2017. Two reviewers evaluated and screened the literature independently for eligibility and extracted data. We evaluated the quality of body of evidence and made a recommendation according to the Grading of Recommendations Development and Evaluation methodology. RESULTS: The search yielded 40 studies, 9 of which were included after the first and second screenings. There were three prospective case series but no randomized controlled trials among the nine studies. There was no case-control report (vs. no treatment). According to Response Evaluation Criteria in Solid Tumors criteria, the mean response rate (complete remission or partial response) was 36% (11-57%). Including stable disease, namely, clinical benefit was consistently as high as 85% (69-100%). Mean adverse event rate of G3 or G4 according to CTCAE was 31%. One study reported improvement of pain (87.5%) because of this chemotherapy. CONCLUSION: The efficacy of this chemotherapy was convincing. However, the overall evidence was weak, and this chemotherapy is not covered by insurance in Japan; we only weakly recommend low-dose chemotherapy with methotrexate and vinblastine in patients with extra-abdominal desmoid-type fibromatosis.

Is mutation analysis of ß-catenin useful for the diagnosis of desmoid-type fibromatosis? A systematic review.

BACKGROUND: An accurate diagnosis is crucial to determine the treatment modality for desmoid-type fibromatosis, although the histopathological diagnosis is occasionally difficult to make. Many desmoid-type fibromatosis have been reported to have hotspot mutation of ß-catenin gene (CTNNB1). In the present study, we performed a systematic review to verify the usefulness of CTNNB1 mutation analysis in the diagnosis of desmoid-type fibromatosis. METHODS: A literature search from January 1990 to August 2017 was conducted. Three reviewers independently assessed and screened the literature for eligibility and determined the final articles to be evaluated. Data regarding the sensitivity, specificity, accuracy and usefulness of CTNNB1 mutation analysis in the diagnosis of desmoid-type fibromatosis were recorded. We rated each report according to the Grading of Recommendations Development and Evaluation approach. RESULTS: The search yielded 90 studies, seven of which were included after the first and second screenings. The positive rate of CTNNB1 mutation in desmoid-type fibromatosis was 86.8%, but the cohort of six of the seven reports was already diagnosed histopathologically as desmoid-type fibromatosis. Therefore, the usefulness of CTNNB1 mutation analysis in a cohort that is difficult to diagnose histopathologically is not clear in this review. Nevertheless, CTNNB1 mutation showed very high specificity in desmoid-type fibromatosis, indicating the usefulness of CTNNB1 mutation analysis in its diagnosis in combination with histological examination. CONCLUSION: Because the lack of data precludes any useful comparison with histological diagnosis, the evidence level is low. However, considering its specificity, CTNNB1 mutation analysis may be useful in cases in which the histopathological diagnosis is difficult.

Is tumour location a prognostic factor for pharmacological treatment in patients with desmoid-type fibromatosis? a systematic review.

BACKGROUND: The mainstay of the treatment for desmoid-type fibromatoses has been shifting from surgery to drug treatment, making accurate prediction of the efficacy of drug treatment of extreme importance. On the other hand, desmoid-type fibromatoses arise everywhere in the body. The purpose of this systematic review was to address the clinical question of whether tumour location has an impact on the efficacy of drug treatment. METHODS: A literature search from January 1990 to August 2017 was conducted. Four reviewers independently assessed and screened the literature for eligibility and determined the final articles. They rated each report according to the Grading of Recommendations Development and Evaluation approach. Based on the quality of 'Body of Evidence', our clinical guideline committee developed a recommendation for the clinical question. RESULTS: In total, 128 articles were extracted. After the screenings, 5 were chosen for the final evaluation. The drugs used in these articles were one each of toremifene, sorafenib, and methotrexate and vinblastine and of meloxicam. There were no randomized controlled trials, and two prospective and three retrospective case series were included. Therapeutic effects were observed slightly more markedly in extremity using meloxicam or methotrexate and vinblastine. In contrast, the efficacy of toremifene was slightly higher in non-extremity. However, the evidence level of all of the reports was judged to be low. CONCLUSIONS: Considering the low evidence level, we concluded that the site-specific therapeutic effects of drugs could not be confirmed in desmoid-type fibromatoses.

Functional evaluation following deltoid muscle resection in patients with soft tissue sarcoma.

BACKGROUND: The present study aimed to determine functional outcomes in patients undergoing deltoid muscle resection for soft tissue sarcoma. METHODS: Between 2002 and 2014, 18 patients with soft tissue sarcoma of the shoulder who underwent wide resection including the deltoid muscle, and were followed up for more than 12 months, were retrospectively included in the study. In all, 11 patients were male and 7 were female. The median age was 59 years, median follow-up duration was 37 months. The extent of resection of deltoid muscle, with or without rotator cuff damage, reconstruction methods, adjuvant therapy, oncological outcomes, and the International Society of Limb Salvage (ISOLS) score as functional outcomes were analyzed. RESULTS: Six patients underwent total resection, and twelve underwent partial resections of deltoid muscle. The rotator cuff was resected in four patients. Soft tissue reconstruction was performed in 17 patients using a pedicled latissimus dorsi muscle flap. Two local recurrences and three distant metastases occurred during follow-up. Median overall survival was 72 months. The mean ISOLS score was 25.0 points (±4.6points). Univariate analysis revealed that there was no significant difference in ISOLS score regarding the extent of deltoid muscle resection. Multivariate analysis identified only combined resection of the rotator cuff as a significant prognostic factor for poor functional outcomes (P < 0.001). CONCLUSIONS: The extent of resection of the deltoid muscle might not affect the functional outcomes determined by ISOLS score. If the rotator cuff is resected concurrently, satisfactory functional outcomes might not be obtained.

Cardiac metastases from primary myxoid liposarcoma of the thigh: a case report.

BACKGROUND: Myxoid liposarcoma is well known to have an unusual proclivity for extrapulmonary metastasis. However, cardiac metastasis of myxoid liposarcoma is very rare, even in patients with advanced disease. CASE PRESENTATION: A 40-year-old man was diagnosed with myxoid liposarcoma of the right thigh and treated with wide resection. Two years after the surgery, a low-density area in the left ventricle was found on follow-up chest computed tomography, and was suspected of being metastatic disease. He underwent surgical treatment, and the lesion was pathologically confirmed as metastasis of myxoid liposarcoma. Fifteen months later, he complained of slight dyspnea and developed metastatic disease in the right atrium. He was treated with surgical excision, followed by radiotherapy. Although there was no recurrence in the heart since the second cardiac metastasectomy, multiple metastases occurred in the abdominal cavity, lungs, and muscles. He finally died of the disease 2 years after the second cardiac metastasectomy. CONCLUSION: We experienced a case of primary myxoid liposarcoma in the thigh, accompanied by ectopic and metachronous cardiac metastases. Although this condition is rare, we should follow-up patients with myxoid liposarcoma, considering the possibility of cardiac metastasis.

Massively parallel sequencing of tenosynovial giant cell tumors reveals novel CSF1 fusion transcripts and novel somatic CBL mutations.

Tenosynovial giant cell tumor (TSGCT) is a rare neoplasm. Although surgical resection is the widely accepted primary treatment for TSGCT, recurrences are frequent, and patients' joint function may be severely compromised. Previous studies reported that CSF1-COL6A3 fusion genes were identified in approximately 30% of TSGCTs. The aim of our study was to comprehensively clarify the genomic abnormalities in TSGCTs. We performed whole exome sequencing in combination with target sequence validation on 34 TSGCT samples. RNA sequencing was also performed on 18 samples. RNA sequencing revealed fusion transcripts involving CSF1, including novel CSF1-VCAM1, CSF1-FN1 and CSF1-CDH1 fusions, in 13/18 (72%) cases. These fusion genes were validated by chromogenic in situ hybridization. All CSF1 fusions resulted in the deletion of CSF1 exon 9, which was previously shown to be an important negative regulator of CSF1 expression. We also found that 12 (35%) of the 34 TSGCT samples harbored CBL missense mutations. All mutations were detected in exons 8 or 9, which encode the linker and RING finger domain. Among these mutations, C404Y, L380P and R420Q were recurrent. CBL-mutated cases showed higher JAK2 expression than wild-type CBL cases (p = 0.013). CSF1 fusion genes and CBL mutations were not mutually exclusive, and both alterations were detected in six of the 18 (33%) tumors. The frequent deletion of CSF1 exon 9 in the fusion transcripts suggested the importance of this event in the etiology of TSGCT. Our results may contribute to the development of new targeted therapies using JAK2 inhibitors for CBL-mutated TSGCT.

Potential drug interactions between pazopanib and proton pump inhibitors/potassium-competitive acid blockers in patients with soft tissue sarcoma.

Because absorption of the oral drug pazopanib depends on gastric pH, concomitant use of proton pump inhibitors (PPIs)/potassium-competitive acid blockers (P-CABs) may inhibit pazopanib absorption by elevating the gastric pH. This study investigated to what extent the concomitant use of PPIs/P-CABs affects treatment with pazopanib in patients with soft tissue sarcoma. We retrospectively reviewed the medical records of patients with soft tissue sarcoma who had received at least one dose of pazopanib at our institution, among which those who had received concomitant PPIs/P-CABs were included in this analysis. Using paired sample t tests, the frequency of dose reduction or interruption of pazopanib and the major adverse events (AEs) were compared in each patient between periods with and without PPIs/P-CABs. Between January 2018 and December 2022, eight patients were eligible. The median time to treatment failure (TTF) was 3.9 months (2.1-38.2 months). Two patients received concomitant PPIs/P-CABs throughout their treatment with pazopanib. Among the other six patients, dose reduction or interruption of pazopanib occurred less frequently (P = 0.021), and neutropenia tended to be milder (P = 0.155) with the concomitant use of PPIs/P-CABs. Although the concomitant use of PPIs/P-CABs had no apparent effect on TTF in patients undergoing pazopanib treatment, dose reduction or interruption of pazopanib occurred less frequently, and neutropenia was milder, suggesting that concomitant use of PPIs/P-CABs might decrease the pharmacological activity of pazopanib. Supplementary Information: The online version contains supplementary material available at 10.1007/s13691-023-00638-2.

Clinical results of active surveillance for extra-abdominal desmoid-type fibromatosis.

BACKGROUND: The treatment of choice for desmoid-type fibromatosis (DF) has been changed to active surveillance (AS). However, few studies have reported clinical outcomes of AS modality in Asian countries. This study aimed to clarify the significance of AS as a DF treatment modality. METHODS: A total of 168 lesions from 162 patients with extra-abdominal DF were included. The mean age at diagnosis was 39 years (1-88 years), and the median maximum tumor diameter at the first visit was 64.1 mm (13.2-255.8 mm). The clinical outcomes of AS and the risk factors requiring active treatment (AT) (defined as an event) from AS modality were investigated. RESULTS: Of the 168 lesions, 94 (56%) were able to continue AS, with a 5-year event-free survival of 54.8%. Of the 68 lesions with PD, 21 (30.9%) lesions were able to continue AS. Neck location (p = 0.043) and CTNNB1 S45F mutation (p = 0.003) were significantly associated with the transition to AT, and S45F mutation was a significant factor associated with the transition to AT by multivariate analysis (hazard ratio: 1.96, p = 0.048). AT outcomes after AS were evaluable in 65 lesions, and 49 (75%) lesions did not require a transition to a second AT. CONCLUSIONS: AS was revealed as an effective treatment modality. The transition to AT needs to be considered for neck location and CTNNB1 S45F mutation DF. Good results can be obtained by selecting a treatment method that considers the tumor location even in cases that require intervention.

Clinical Outcome in Patients With High-grade Soft-tissue Sarcoma Receiving Prosthetic Replacement After Tumor Resection of the Lower Extremities: Tokai Musculoskeletal Oncology Consortium Study.

AIM: This multicenter retrospective study aimed to clarify the surgical and oncological outcomes of patients with high-grade soft tissue sarcoma (STS) who underwent prosthetic replacement reconstruction after lower extremity tumor resection. PATIENTS AND METHODS: We retrospectively collected the data of 27 patients with high-grade STS. The mean follow-up duration after prosthetic replacement was 44.7 months. RESULTS: The mean age at surgery was 63 years. The mean tumor size was 16 cm. For reconstruction, proximal femur replacement was performed in 15 patients, distal femur replacement in six, and total femur replacement in six. The major complications were infections in nine patients and aseptic loosening in four. Nine patients developed local recurrence. The cause of revision surgery was infection in five patients, aseptic loosening in three, and metal allergy in one. The 5-year prosthetic survival rate was 51.1%. At the final follow-up, amputation was performed in five patients. The 5-year limb salvage rate was 76.8%. The mean functional score of the 25 patients who could be assessed was 16.0 (53%). Of the 27 patients, five were excluded from the survival analysis because they underwent prosthetic replacement for local recurrence. The 5-year overall survival rate in the remaining 22 patients was 45.3%. CONCLUSION: We identified a high rate of surgical complications and poor survival in patients with high-grade STS who underwent tumor resection and reconstruction using prosthetic replacement of the lower extremities, although limb salvage was achieved in 81.5% of the patients. Careful follow-up is needed for surgical complications and oncological events after surgery.

Hyaluronan in articular cartilage: Analysis of hip osteoarthritis and osteonecrosis of femoral head.

Hyaluronan (HA) plays crucial roles in the maintenance of high-quality cartilage extracellular matrix. Several studies have reported the HA in synovial fluid in patients with osteoarthritis (OA), but few have described the changes of HA in articular cartilage of OA or idiopathic osteonecrosis of the femoral head (ONFH). KIAA1199 was recently reported to have strong hyaluronidase activity. The aim of this study was to clarify the HA metabolism in OA and ONFH, particularly the involvement of KIAA1199. Immunohistochemical analysis of KIAA1199 and HA deposition was performed for human OA (n = 10), ONFH (n = 10), and control cartilage (n = 7). The concentration and molecular weight (MW) of HA were determined by competitive HA ELISA and Chromatography, respectively. Regarding HA metabolism-related molecules, HAS1, HAS2, HAS3, HYAL1, HYAL2, and KIAA1199 gene expression was assessed by reverse transcriptase polymerase chain reaction. Histological analysis showed the overexpression of KIAA1199 in OA cartilage, which was accompanied by decreased hyaluronic acid binding protein (HABP) staining compared with ONFH and control. Little KIAA1199 expression was observed in cartilage at the collapsed area of ONFH, which was accompanied by a slight decrease in HABP staining. The messenger RNA (​​​​​mRNA) expression of HAS2 and KIAA1199 was upregulated in OA cartilage, while the mRNA expression of genes related to HA catabolism in ONFH cartilage showed mostly a downward trend. The MW of HA in OA cartilage increased while that in ONFH cartilage decreased. HA metabolism in ONFH is suggested to be generally indolent, and is activated in OA including high expression of KIAA1199. Interestingly, MW of HA in OA cartilage was not reduced.

Significance of expression of CD109 in osteosarcoma and its involvement in tumor progression via BMP signaling.

Osteosarcoma, the most common primary malignant bone tumor, is defined by the formation of neoplastic osteoid and/or bone. This sarcoma is a highly heterogeneous disease with a wide range of patient outcomes. CD109 is a glycosylphosphatidylinositol-anchored glycoprotein that is highly expressed in various types of malignant tumors. We previously reported that CD109 is expressed in osteoblasts and osteoclasts in normal human tissues and plays a role in bone metabolism in vivo. While CD109 has been shown to promote various carcinomas through the downregulation of TGF-ß signaling, the role and mechanism of CD109 in sarcomas remain largely unknown. In this study, we investigated the molecular function of CD109 in sarcomas using osteosarcoma cell lines and tissue. Semi-quantitative immunohistochemical analysis using human osteosarcoma tissue revealed a significantly worse prognosis in the CD109-high group compared with the CD109-low group. We found no association between CD109 expression and TGF-ß signaling in osteosarcoma cells. However, enhancement of SMAD1/5/9 phosphorylation was observed in CD109 knockdown cells under bone morphogenetic protein-2 (BMP-2) stimulation. We also performed immunohistochemical analysis for phospho-SMAD1/5/9 using human osteosarcoma tissue and found a negative correlation between CD109 expression and SMAD1/5/9 phosphorylation. In vitro wound healing assay showed that osteosarcoma cell migration was significantly attenuated in CD109-knockdown cells compared with control cells in the presence of BMP. These results suggest that CD109 is a poor prognostic factor in osteosarcoma and affects tumor cell migration via BMP signaling.