Normal Bone Tissue Research Articles

Imbalanced Diet Deficient in Calcium and Vitamin D- Induced Juvenile Osteopenia in Rats; the Potential Therapeutic Effect of Egyptian Moghat Roots Water Extract (Glossostemon bruguieri).

This study aimed to explore and validate a new juvenile osteopenic (JO) rat model then examine the efficacy of moghat (Glossostemon bruguieri) as an alternative reversal therapy for JO. Phytochemical screening analysis showed that moghat contains 5.8% alkaloids, 1.5% flavonoids and 13.2% total phenols. Juvenile osteopenia was induced in 15 days old Sprague- Dawley female rats by feeding them free Ca and vitamin D synthetic diet for 21 days. Osteopenic rats were either treated with moghat (0.8 g dried plant tissue/Kg body weight, orally), or with a reference nutritional supplements of calcium chloride (14 mg Ca/Kg) and vitamin D3 (7 IU/Kg), for extra 21 days. Both untreated and treated groups were compared to a control group that fed a regular pelleted food. Our results showed that osteopenic rats lost normal bone tissue architecture, 30 % of body mass, 54 % of bone mass and finally 93% of bone calcium mass. Furthermore, these rats showed a markedly increase in serum phosphate, PTH, alkaline phosphatase, aspartate transaminase activities and creatinine level as compared to the control group. Moghat administration was successfully reversed osteopenia by normalizing body and bone masses to the reference ranges, increased the bone calcium mass by 17 fold without any detectable side effects on liver and kidney physiological performance. Therefore, moghat could be considered as potent safe -JO- reversal extract.

RETRACTED: miR-126 Functions as a Tumor Suppressor in Osteosarcoma by Targeting Sox2

Osteosarcoma (OS) is the most common malignant bone tumor in children and young adults, the early symptoms and signs of which are non-specific. The discovery of microRNAs (miRNAs) provides a new avenue for the early diagnosis and treatment of OS. miR-126 has been reported to be highly expressed in vascularized tissues, and is recently widely studied in cancers. Herein, we explored the expression and significance of miR-126 in OS. Using TaqMan RT-PCR analysis, we analyzed the expression of miR-126 in 32 paired OS tumor tissues and 4 OS cell lines and found that miR-126 was consistently under-expressed in OS tissues and cell lines compared with normal bone tissues and normal osteoblast cells (NHOst), respectively. As miR-126 is significantly decreased in OS tissues and cell lines, we sought to compensate for its loss through exogenous transfection into MG-63 cells with a miR-126 mimic. Ectopic expression of miR-126 inhibited cell proliferation, migration and invasion, and induced apoptosis of MG-63 cells. Moreover, bioinformatic prediction suggested that the sex-determining region Y-box 2 (Sox2) is a target gene of miR-126. Using mRNA and protein expression analysis, luciferase assays and rescue assays, we demonstrate that restored expression of Sox2 dampened miR-126-mediated suppression of tumor progression, which suggests the important role of miR-126/Sox2 interaction in tumor progression. Taken together, our data indicate that miR-126 functions as a tumor suppressor in OS, which exerts its activity by suppressing the expression of Sox2.

Up-regulated isocitrate dehydrogenase 1 suppresses proliferation, migration and invasion in osteosarcoma: In vitro and in vivo

Very few studies have been reported the function of wild type IDH1 in tumor progress. Previously, we reported that IDH1 correlated with pathological grade and metastatic potential inversely in human osteosarcoma. Here, IDH1 was found lower expressed in osteosarcoma tissues than that of adjacent normal bone tissues. In addition, we observed in vitro anti-proliferation and pro-apoptosis effects of up-regulated IDH1 on osteosarcoma cell lines. The migration and invasion activity was also markedly reduced by IDH1 up-regulation. Unexpectedly, IDH1 up-regulation also suppressed tumor growth and metastasis in vivo. Therefore, IDH1 may represent a potential novel treatment and preventive strategy for osteosarcoma.

Overexpression of steroid receptor coactivator-3 in bone cancers: An in vivo immunohistochemical study with tissue microarray

Bone tissue is steroid-responsive and profoundly regulated by steroids and/or their receptors. Bone cancers (either primary or metastatic) belong to the most dangerous tumors. Previous studies have demonstrated overexpression of steroid receptor coactivator-3 (SRC-3) in many cancers, such as breast cancer, prostate cancer, thyroid cancer, functioning in the regulation of cancer cell proliferation, invasion, and metastasis. However, so far, the expression and function of SRC-3 in bone cancers have not yet been clarified. In this study, nickel-intensified immunohistochemistry was conducted using a commercial tissue microarray (with 94 cases of bone cancer tissue and 10 normal bone tissues), and the 4-scoring system was employed to evaluate the expression levels of SRC-3 immunoreactivity. The results showed that in normal bone tissue, levels of SRC-3 are almost negative (score=0), the total positivity (score=1–3) of SRC-3 immunoreactivities in bone cancers was 74.47%. There were no significant differences in gender, status (malignant or benign) or (mean) age (p>0.05). The percentage of positivity was 77.78% in osteogenic tumors, 58.82% in cartilage tumors, 70% in giant cell tumors, 100% in hematopoietic tumors, 77.78% in miscellaneous lesions, and 75% in miscellaneous tumors. Age related differences of SRC-3 immunoreactivities were detected in cartilage tumors and giant cell tumors (p<0.05). The above results clearly demonstrated a high frequency of overexpression of SRC-3 immunoreactivities in different bone cancers, indicating its potential roles in the prognosis and treatment of these cancers.

High expression of MACC1 predicts poor prognosis in patients with osteosarcoma

Increasing evidence has demonstrated that high metastasis-associated in colon cancer-1 (MACC1) level is tightly associated with the development, progression, and poor prognosis of a variety of tumors. However, the relationship between MACC1 and the occurrence, development, and progression of osteosarcoma (OS) remains to be clarified. To facilitate and deepen the understanding of the associations of MACC1 with the development and progression of OS, in the current study, we detected the expressions of MACC1 mRNA and protein, and investigated the relationship between MACC1 expression and prognosis of the patients with OS. Our findings demonstrated that expressions of MACC1 mRNA and protein in OS tissues were significantly higher than those in paired normal bone tissues (P < 0.05). Additionally, the level of MACC1 mRNA in the patients with higher clinical stage and distant metastasis was markedly higher than those with lower clinical stage and without metastasis (P < 0.05). Furthermore, high MACC1 level was closely correlated with clinical stage and distant metastasis (P < 0.05), but not related to the patients' age, gender, tumor size, and anatomical location (P > 0.05). Stepwise investigation revealed that survival time of the patients with high MACC1 level was obviously lower than that with low MACC1 level (P < 0.05). Collectively, our data suggest that MACC1 may play important roles in the development and progression of OS, and thus may be considered as a novel molecular target for therapy of the patients with OS.

CIP2A is overexpressed in osteosarcoma and regulates cell proliferation and invasion

Cancerous inhibitor of protein phosphatase 2A (CIP2A) is a newly characterized oncoprotein involved in a variety of malignant tumors. However, its expression pattern and biological functions in osteosarcoma remain unclear. In the present study, CIP2A expression was analyzed in 51 human osteosarcoma specimens using immunohistochemistry. CIP2A siRNA was used in the MG-63 cell line, and the effect of CIP2A depletion on cell proliferation and invasion was evaluated. We found that CIP2A was overexpressed in 76.5 % (39/51) of osteosarcoma tissues, while normal bone tissues showed negative CIP2A expression. In addition, the positive rate of CIP2A expression was higher in stage IIB osteosarcoma than stage IIA cases. Knockdown of the CIP2A expression significantly reduced osteosarcoma cell proliferation and invasion, with decreased c-Myc expression and p-AKT expression. CIP2A depletion also facilitated apoptosis and inhibited MMP9 mRNA expression. Taken together, our data identified CIP2A as a critical oncoprotein involved in cell proliferation and invasion, which could serve as a therapeutic target in osteosarcoma.

Determination of the Elastic Modulus of Hydroxyapatite Doped with Magnezium through Nondestructive Testing

In this paper there are presented determination methods of longitudinal elasticity modulus based on processing and analysis of vibration signals which are the results of an impulse from a small rigid ball applied on some samples of hydroxyapatite with discoid form. Hydroxyapatite is a bioactive bioceramics used, usually in implants, rods and screws covering, in order to allow human tissue to adhere to implant surface. In order to improve mechanical properties of hydroxyapatite it is doped with magnesium. This chemical element exists in normal bone tissue; it doesnt create any compatibility problem and has a stabilizing role in heat treatments stopping undesirable phase transformations.

Pharmacokinetics of 188Re-labeled pentaphosphonic acid in rats with experimental bone callosity

The influence of modeled femur callosity on the biodistribution of 188Re-labeled pentaphosphonic acid (188Re-PPA) in rats was studied. The radiopharmaceutical was injected into a tail vein 14 d after fracture. It was established that the presence of bone callosity had a significant influence on 188Re-PPAbiodistribution in soft tissues and organs. 188Re-PPA showed good stability in vivo because its uptake by thyroid gland was low compared to that of unbound 188Re. The maximum activity levels were observed in bone callosity (up to 1%/g), bone tissue in general, liver, and kidneys. The 188Re-PPAconcentration in bone tissue of rats with bone callosity was 2.4 – 10.6 times lower than that in bone tissue of intact animals. The maximum 188Re-PPAactivity in bone tissue of intact rats and those with bone callosity 1 h after i.v. injection was 2.12 and 0.42%/g, respectively. The coefficients of differential accumulation (CDA) of drug activity in bone callosity relative to soft tissues and organs were calculated. 188Re-PPAuptake by bone lesion was greater than that by normal bone tissue. The CDA values enabled the accumulation dynamics and elimination rate of 188Re-PPA from soft tissues and organs to be compared with those from bone fracture. In addition, the CDA values allowed the optimum period for carrying out skeletal scintigraphic studies using a gamma camera to be determined. In conclusion, 188Re-PPA had appropriate biological characteristics for use as a bone-pain pallation agent for the treatment of bone metastases.

Proline/Arginine-Rich End Leucine-Rich Repeat Protein Converts Stem Cells to Ligament Tissue and Zn(II) Influences Its Nuclear Expression

Our objective was to facilitate ligament tissue reconstruction by characterizing the mechanism of expression of ligament tissue. To accomplish this, we searched for proteins specific to the tissue and introduced them into mesenchymal stem cells. In the two-dimensional phosphorescent gel electrophoresis, the spots in common with the normal human ligament tissue were selected after removing the spots of the normal bone tissue from those of the ossified tissue in the spinal ligament. Proline/arginine-rich end leucine-rich repeat protein (PRELP) was identified in ligament-specific locations by liquid chromatography-tandem mass spectrometry. Transfection of PRELP into mouse mesenchymal stem cells yielded ligament-like connective tissue comprised of parallel fibers. Thus, expression of the PRELP protein could reconstruct the ligament tissue. Since zinc-related proteins were found with high incidence as a result of an array analysis of PRELP's ProtoArray, it was considered that there is a relationship to the zinc metabolism. Tissue induction was mediated by the tumor necrosis factor (TNF)-α via the zinc pathway. PRELP may be a useful gene in syndesmoplasty, provided zinc is present for tissue reconstruction. Chromosome division becomes active with the addition of zinc, and rapid tissue induction takes place in the presence of zinc and TNF-α. Currently, the reconstruction of a ruptured ligament tissue is difficult, but we expect that the PRELP protein expression may facilitate this process. This study describes the discovery of the gene responsible for the differentiation of stem cells into ligament tissue. This important finding may lead to treatments for gonarthrosis, cruciate ligament, and periodontal ligament ruptures, and ossification of the posterior longitudinal ligament.

Nasal Polyp With Heterotopic Bone Formation (Osseous Metaplasia): A Case Report

Osseous metaplasia is defined by the presence of heterotopic normal bone tissue in a soft tissue. Metaplastic ossification is a rare event in nasal polyps. The authors describe a rare case of bone formation in nasal polyp of a 28-year-old man with chronic right-sided nasal obstruction without history of trauma or allergy symptoms. To our knowledge, this finding has been reported in a few cases in the English medical literature.

Gene expression of the MAPK pathway in osteosarcoma.

10534 Background: Osteosarcoma (OS) is the most common malignant bone tumor in adolescents. A feature of the OS is its high risk of lung metastasis. Unlike other sarcomas, OS does not have genetic markers. We suggest that abnormalities in the expression levels of genes involved in important cell signaling pathways, as MAPKs pathway, may contribute to OS progression and aggressiveness. In a recent study, we found an overexpression of MAPK7 gene in prechemotherapy specimens when compared to postchemotherapy specimens and when compared with normal bone. This previous study suggests that MAPK7 overexpression may be contributing to the worse response to treatment and therefore a poor overall survival. To understand the relationship between the OS genesis process and the MAPK pathway, we investigated the expression of genes involved in the regulation of MAPK pathway (MAP2K5, MAP2K6, MAP3K1, MAP3K3, MAP4K3 and DUSP1). Methods: Total RNA was extracted from 68 tumor samples obtained from 28 patients (28 prechemotherapy specimens, 28 postchemotherapy specimens and 12 metastasis specimens) and five normal bone tissues. cDNA was synthesized and expression of the six genes were determined by quantitative real-time PCR. Clinical variables were correlated with gene expression. Results: MAP2K6 and MAP4K3 had a similar gene expression profile. Both genes were overexpressed in postchemotherapy specimens and were strongly associated with important clinical parameters as presence of metastasis (P=0.0159 and P=0.0014, respectively), shorter overall survival (P=0.0040 and P=0.0040, respectively) and disease progression (P=0.0142 and P=0.0109, respectively). DUSP1 overexpression in postchemotherapy specimens was related with metastasis at diagnosis (P=0.0004), worse response to treatment (P=0.0009) and disease recurrence (P=0.0039). MAP2K5, MAP3K1 e MAP3K3 showed no significant correlations in the present study. Conclusions: The overexpression of MAP2K6, MAP4K3 and DUSP1 in postchemotherapy specimens presented a significant association with poor prognosis. The current study suggests that these genes could play an important role in OS tumorigenesis and may be in the future new therapeutic targets in OS treatment.

Primary Intraosseous Hemangioma in the Frontal Bone

Primary Intraosseous Hemangioma in the Frontal Bone

Trabecular bone score and bone mineral density in Ukrainian normal women depending on duration of postmenopausal period

Aim: To evaluate the features of pain syndrome in knee joints, functional activity and quality of life in postmenopausal women with knee osteoarthritis (KOA) depending on parameters of bone mineral density (BMD). Materials and methods: We have examined 240 postmenopausal women aged 60–79 years with knee osteoarthritis of II–III degree, which were divided into two age groups: the 60–69 and 70–79 years old. The diagnosis of knee osteoarthritis was performed according to the criteria of ACR (1995), the stage – by Kellgren–Lawrence classification. The parameters of pain syndrome in knee joints and functional activitywere assessedby visual analogue scale, index Lequense and15-meter test; thequality of life was determined by Euro-Qol-5D. Bone mineral density was measured byDual-energy X-ray absorptiometry («Prodigy», GEMedical systems, Lunar, model 8743, 2005). To analyze the data all patients were subdivided into two groups: 1 – patients with osteoporosis and 2 – with normal BMD. Results: In patients with osteoporosis in the age group 60–69 it was found significantly higher levels of pain in the knee joints compared with women with normal BMD. Thus, the pain during upstairs walking were 7.0±2.4 and 4.8±2.6 points accordingly (F=4.27, p=0.05), pain during walking down – 8.4±0.9 and 4.9±2.9 points respectively (F=7.09, p=0.01). In patients with osteoporosis in the age group 70–79 it was found significantly lower parameters of Lequense index compared with women with normal bone tissue: 17.8±3.1 and 13.9±5.0 points respectively (F=4.96, p=0.03). All patients with KOA didnt significantly differ in data of 15-meter test and quality of life depending on the status of BMD. Conclusions: BMDparameters in postmenopausalwomen aged 60–79 years with KOA of II–III degree significantly effect the data of pain syndrome and functional activity.

Regulation of β‐catenin localization by retinoblastoma protein in osteoblasts

pRb is a tumor suppressor that plays an important role in the coactivation of the osteoblast‐specific transcription factor Runx2. It has been shown that osteosarcomas are characterized by high rates of inactivation of both pRb and Wnt. The aim of this study is to determine whether pRb is capable of affecting Wnt signaling by regulating β‐catenin localization, hypothesizing that pRb activity is necessary for Wnt activation. We performed immunocytology (IC) for β‐catenin in cultured pRb‐expressing and pRb‐deficient MC3T3 cell lines in order to assess β‐catenin localization. In addition, a β‐catenin immunohistochemical (IHC) analysis was done on normal bone and osteosarcoma tissues. IC qualitative results showed an increase in nuclear β‐catenin localization in the presence of a functional pRb. Our IHC confirmed a correlation between pRb and β‐catenin localization. Interestingly, in osteosarcoma tissues we observed a correlation (Spearman r = 0.9878), in which pRb's localization determines β‐catenin's localization. Importantly, we observed that cells with cytoplasmic pRb in osteosarcoma tissues also had cytoplasmic β‐catenin localization, again strengthening the idea that a functional pRb is needed to activate Wnt. We concluded that pRb promotes β‐catenin nuclear re‐localization, showing that pRb plays an important role in the regulation of Wnt signaling.

ErbB3 silencing reduces osteosarcoma cell proliferation and tumor growth in vivo

Osteosarcoma is the most common primary bone tumor in children and adults. Despite improved prognosis, resistance to chemotherapy remains responsible for failure of osteosarcoma treatment. The identification of the molecular signals that contribute to the aberrant osteosarcoma cell growth may provide clues to develop new therapeutic strategies for chemoresistant osteosarcoma. Here we show that the expression of ErbB3 is increased in human osteosarcoma cells in vitro. Tissue microarray analysis of tissue cores from osteosarcoma patients further showed that the ErbB3 protein expression is higher in bone tumors compared to normal bone tissue, and is further increased in patients with recurrent disease or soft tissue metastasis. In murine osteosarcoma cells, silencing ErbB3 using shRNA decreased cell replication, cell migration and invasion, indicating that ErbB3 contributes to tumor cell growth and invasiveness. Furthermore, ErbB3 silencing markedly reduced tumor growth in a murine allograft model in vivo. Immunohistochemal analysis showed that the reduced tumor growth induced by ErbB3 silencing in this model resulted from decreased cell osteosarcoma cell proliferation, supporting a role of ErbB3 in bone tumor growth in vivo. Taken together, the results reveal that ErbB3 expression in human osteosarcoma correlates with tumor grade. Furthermore, silencing ErbB3 in a murine osteosarcoma model results in decreased cell growth and invasiveness in vitro, and reduced tumor growth in vivo, which supports the potential therapeutic interest of targeting ErbB3 in osteosarcoma.

The Improved Biological Performance of a Novel Low Elastic Modulus Implant

BackgroundThe mismatch of the elastic modulus between implants and bone tissue can lead to stress shielding, bone resorption and poor osseointegration. Compared with normal bone tissue, this problem is much more serious in osteoporosis. The purpose of this study was designed to find out whether the novel Ti-24Nb-4Zr-7.9Sn (TNZS) implant with low elastic modulus and high strength was suitable for biomedical material, especially in osteoporosis.Methodology In vitro study, the viability and Alkaline phosphatase (ALP) activity of osteoblasts on the TNZS and Ti-6V-4V (TAV) were observed. In vivo study, 30 adult female New Zealand rabbits were selected and divided randomly into two groups: sham-operation (SHAM, n = 6) and ovariectomised in combination with methylprednisolone treatment (OVX+MP, n = 24). Two implants were then placed in the tibia of each OVX + MP group rabbit, one in each side (left: TAV; right: TNZS). The OVX + MP group rabbits were sacrificed at 4 and 12 weeks after the implantation. The osteoporotic bone responses to the TNZS and TAV implants were evaluated by pull-out test, Micro-CT analyses and histological observation.Principal FindingsCompared with the TAV group, the TNZS group showed a significant increase (P<0.05) in cell viability and ALP activity, new bone formation and pull-out force.ConclusionsThe novel TNZS implants show good biological performance both in vitro and in vivo, which suggests that the alloys are suitable for biomedical applications, especially in osteoporosis.

Research for Proteomics Discrepancies between Osteosarcoma and Normal Bone Tissue

Research for Proteomics Discrepancies between Osteosarcoma and Normal Bone Tissue

Quantification of 99mTc-DPD concentration in the lumbar spine with SPECT/CT.

BackgroundRoutine single-photon emission computed tomography (SPECT) currently lacks quantitative information on regional activity concentration (ACC) of the injected tracer (e.g. kBq/ml). Furthermore, little is known on the skeletal absolute concentration of 99mTc-DPD after intravenous injection in bone scintigraphy. The aim of this study is to determine ACC in the healthy lumbar vertebrae of patients using a recently published quantitative SPECT/computed tomography (CT) protocol.MethodsLumbar vertebrae ACC estimates were performed in 50 female patients (mean age 69.88 ± 13.73 years) who had been administered 562.84 ± 102.33 MBq of 99mTc-DPD and had undergone SPECT acquisition 4 h after the injection. The SPECT/CT system was calibrated against a well counter. Images were reconstructed with Flash3D. ACC and CT tissue density were measured in volumes of interest drawn over the spongious bone tissue of the three lower lumbar vertebral bodies when these exhibited no focal CT or SPECT pathology.ResultsAverage ACC measured in the normal spongious bone tissue was 48.15 ± 13.66 kBq/ml (95% confidence interval (CI) 45.81 to 50.50 kBq/ml). This corresponds to a mean standardised uptake value (SUV) of (5.91 ± 1.54) (95% CI (5.64 to 6.17) SUV). SUV correlated significantly with Hounsfield units (HU) (r = 0.678, p < 0.0001). Significant negative correlations were observed between age and HU (r = −0.650, p < 0.0001) and between age and SUV (r = −0.385, p < 0.0001).ConclusionsThe SUVs determined for 99mTc-DPD uptake 4 h post injection are in the same range as those reported for [18F]fluoride in positron emission tomography. The strong correlation of SUV with bone CT density underlines the physiological significance of this variable. Our data suggest further investigation of the potential value of ACC measurement in the diagnosis of pathological conditions such as osteoporosis or in following up osseous metastases under therapy.

Reduced mitochondrial DNA copy number in Chinese patients with osteosarcoma

A plethora of somatic mutations and germline variations in mitochondrial DNA (mtDNA) have been increasingly reported in numerous cancer entities including osteosarcoma. However, it remains largely unclear whether mtDNA copy number changes occur during the multistep process of osteosarcoma carcinogenesis. For this purpose, we determined quantitative mtDNA levels in 31 primary osteosarcoma specimens and 5 normal bone tissue samples using a real-time polymerase chain reaction assay. Our data showed that the average mtDNA amount was significantly reduced in osteosarcoma tissues compared with normal bone controls. The copy number of mtDNA was statistically associated with tumor metastasis. There was an approximately 2-fold decrease of mtDNA quantity in tumors with metastasis than that in low-grade tumors without metastasis. Furthermore, change in mtDNA content was linked with somatic mutations in the D-loop regulatory region. Tumors carrying somatic D-loop mutations, at the polycytidine stretch between nucleotide positions 303 and 309 or close to the replication origin sites of the heavy strand, had significantly lowered mtDNA levels in comparison with those without mutations. Taken together, these results provide evidence for the first time that reduced mtDNA content may be critically implicated in the development and/or progression of osteosarcoma. Somatic D-loop mutation is likely one key factor among others leading to altered mtDNA amount in osteosarcoma.

SASH1 regulates proliferation, apoptosis, and invasion of osteosarcoma cell

SASH1, a member of the SLY-family of signal adapter proteins, is a candidate tumor suppressor in breast and colon cancer. The SASH1 protein possesses both the SH3 and SAM domains, indicating that it may play an important role in intracellular signal transduction. Reduced expression of SASH1 is closely related to tumor growth, invasion, metastasis, and poor prognosis. However, the biological role of SASH1 remains unknown in osteosarcoma. To unravel the function of SASH1, we explored the expression of SASH1 in osteosarcoma tissues and its correlation to the clinical pathology of osteosarcoma and analyzed the relationship between SASH1 expression and cell cycle, apoptosis and invasion of osteosarcoma MG-63 cells, using the flow cytometry analysis and transwell invasion chamber experiments. Furthermore, the effect of SASH1 on the expression of cyclin D1, caspase-3, matrix metalloproteinase (MMP)-9 were observed by western blot. Our results showed that the expression rate of SASH1 mRNA in osteosarcoma tissues was significantly lower than that in normal bone tissue (p = 0.000), that the expression rate of SASH1 mRNA in the carcinoma tissues from patients with lung metastasis was significantly lower than that from patients without lung metastasis (p = 0.041), and that the expression rate of SASH1 mRNA also decreased with increasing Enneking stage (p = 0.032). However, the mRNA expression of SASH1 in osteosarcoma was independent of the patient's gender, age, and tumor size (p = 0.983, 0.343, 0.517, respectively). The SASH1 protein displayed a down-regulation in osteosarcoma tissues compared to normal bone tissue (p = 0.000), displayed a down-regulation in osteosarcoma tissues from patients with lung metastasis compared to from patients without lung metastasis (p = 0.000), and displayed a gradual decrease with increasing Enneking stage (p = 0.000). In addition, the MG-63 cells from pcDNA3.1-SASH1 group exhibited significantly reduced cell viability, proliferation, and invasive ability compared to the empty vector group and blank control group (p = 0.023, 0.001, respectively), and there was no difference between the empty vector group and blank control group. The pcDNA3.1-SASH1 group displayed significantly more apoptotic cells than the empty vector group and blank control group (p = 0.004). The expression of cyclin D1, MMP-9 displayed a down-regulation in MG-63 cells from pcDNA3.1-SASH1 group compared to the empty vector group and blank control group (p = 0.000, 0.001, respectively) and the expression levels of caspase-3 displayed an up-regulation in MG-63 cells from pcDNA3.1-SASH1 group compared to the empty vector group and blank control group (p = 0.000). Taken together, these data indicated that the overexpression of SASH1 might be associated with the inhibition of growth, proliferation, and invasion of MG-63 cells and the promotion of apoptosis of MG-63 cells.