HIF-1α suppresses myeloma progression by targeting Mcl-1.

HIF-1α is involved in the carcinogenesis and progression of multiple types of cancer. However, the precise role of HIF-1α is unclear in multiple myeloma. Through the qRT-PCR and CCK-8 assays, we demonstrated that silencing the expression of HIF-1α and Mcl-1, MM proliferation can be decreased and apoptosis can be induced. Next, using the GEO database, we found that Mcl-1 was increased in MMs. Mcl-1 overexpression counterbalanced the tumor suppressing effect of siHIF-1α on MM apoptosis. Additionally, HIF-1α acting as a transcription factor, could directly target the promoter region of Mcl-1 to promote Mcl-1 expression. Based on the experimental result, our findings strongly suggest that HIF-1α regulated the progression of MMs by directly targeting the Mcl-1.

Magnetic resonance imaging of temporomandibular joint: morphometric study of asymptomatic volunteers.

BACKGROUND: The aims of this study were to determine the best suited magnetic resonance imaging scanning plane, scanning sequence, and imaging modality for the evaluation of the temporomandibular joint (TMJ) and quantitatively assess the relationship of articular disk position to condyle position. METHODS: One hundred four TMJs in 52 symptom-free heads were examined by magnetic resonance imaging. The best scanning plane, scanning sequence, and scanning parameter were determined according to the imaging time and image quality. Bilateral symmetry of the articular disk and mandibular condyle was measured by using the automatic measurement of 3.0-T GE Excite Signa MR scanner. RESULTS: Fast spin-echo sequence, oblique sagittal imaging plane, and proton density imaging were the best suited scanning sequence, scanning planes, and imaging modality, respectively. The thicknesses of the anterior and posterior bands and for the intermediate zone were not statistically different for both sides. The posterior band of the disk was found to originate in an area adjacent to the 12-o'clock position of the condyle (± 5 degrees), whereas the anterior band of the disk originated adjacent to 1-o'clock position (28 ± 6 degrees). The anteroposterior diameter and mediolateral diameter of the condylar processes were not statistically different for both sides. The axial condylar angle between the plane of the greatest mediolateral diameter of the condylar processes and the midsagittal plane were also not statistically different for both sides. CONCLUSIONS: The magnetic resonance images can depict clearly major regional anatomic structures and position in the TMJ, which can be used in the early diagnosis for the TMJ disorder.

miR-638 suppresses cell proliferation in gastric cancer by targeting Sp2.

BACKGROUND: MicroRNAs play important roles in the development and progression of various cancers. Recent studies have shown that miR-638 was downregulated in several tumors; however, its role in gastric cancer (GC) has not been investigated in detail. AIMS: The purpose of this study was to determine the role of miR-638 and to elucidate its regulatory mechanism in GC. METHODS: The expression levels of miR-638 and specificity protein 2 (Sp2) were detected by real-time PCR and Western blotting in GC. After pcDNA6.2-GW/EmGFP-miR-638 vector, miR-638 inhibitor and Sp2-siRNA transfection, the AGS cell proliferation was investigated by MTT assay and cell cycle, and apoptosis was detected using the Annexin V/PI. In addition, the regulation of Sp2 by miR-638 was evaluated by real-time RT-PCR, Western blot and luciferase reporter assays; cyclin D1 expression was measured by Western blotting. RESULTS: The expression of miR-638 is dramatically down-regulated and Sp2 expression is remarkably up-regulated in GC tissues. Luciferase assays revealed that miR-638 inhibited Sp2 expression by targeting the 3'-UTR of Sp2 mRNA. Overexpression of miR-638 and Sp2-siRNA reduced Sp2 expression at both the mRNA and protein levels in vitro, and inhibition of miR-638 increased Sp2 expression. Moreover, we found that miR-638 overexpression and Sp2-siRNA markedly suppressed cell proliferation with decreasing expression of cyclin D1 and inducing G1-phase cell-cycle arrest in vitro; inhibition of miR-638 significantly promoted cell proliferation by increasing expression of cyclin D1 and leading more cells into the S and G2/M phase. CONCLUSIONS: Our results demonstrated that miR-638 suppressed GC cell proliferation by targeting Sp2 with influence on the expression of cyclin D1. We suggest that miR-638 might be a candidate predictor or an anticancer therapeutic target for GC patients.

[Expression and significance of P75 neurotrophin receptor in oral squamous cell carcinoma].

PURPOSE: To investigate the expression of P75NTR in oral squamous cell carcinoma and evaluate the possibilities of P75NTR as a prognostic indicator of oral squamous cell carcinoma as well as a marker of cancer stem cell. METHODS: SP immunohistochemical method was used to detect the expressions of tongue squamous cell carcinoma line Tca8113 and 43 surgically resected squamous cell carcinoma tissues. Five peri-carcinoma tissues and 8 normal tissues were selected as control. SPSS16.0 software package was applied for X(2) test. RESULTS: P75NTR was positive in the Tca8113 cell line and located in the cell membrane. Thirty-three cases of the 43 OSCC patients showed positive expression of P75NTR. Para-carcinoma tissues and normal tissues showed negative expression of P75NTR. Positive P75NTR located in the cell membrane and dispersed in the cancer nest, and had a trend of cluster distribution. The expression of P75NTR had a relationship with tumor clinical stage(P<0.05) and lymph node metastasis(P<0.05). CONCLUSIONS: The expression of P75NTR can predict the prognosis of oral squamous cell carcinoma, yet it can not be taken as a marker of cancer stem cell alone. Further study should be taken to investigate the role and mechanism of P75NTR in the development of tumor.