RESUMO
Integrin αVß3 is a structural protein of the plasma membrane that transduces signals from extracellular matrix proteins and has recently been shown to contain a novel receptor for thyroid hormone. Thyroid hormone signals are converted by αVß3 into mitogen-activated protein kinase (MAPK) (ERK1/2) activation and downstream intracellular events in the cell nucleus. The latter include post-translational modification of the nuclear thyroid hormone receptor (TRß1) and complex cellular or tissue responses, such as hormone-induced angiogenesis via basic fibroblast growth factor release. The integrin receptor for thyroid hormone has been shown to mediate proliferative effects of the hormone on certain tumor cell lines, including murine glioma/glioblastoma cells and human breast cancer (MCF-7) cells. More than one mechanism may account for this hormonal action, but in vitro studies indicate a direct hormonal action on cellular proliferation. Other possible mechanisms involve indirect actions via the release of tumor growth factors and effects on cell migration. In the intact organism, support of tumor growth by thyroid hormone is postulated to include angiogenesis. Crosstalk between the integrin thyroid hormone receptor and the epidermal growth factor receptor on the plasma membrane may be another mechanism by which thyroid hormone may modify tumor cell growth. Tetraiodothyroacetic acid (tetrac) is an iodothyronine analog that has no agonist activity at the integrin receptor, but inhibits binding of l-thyroxine and 3,5,3´-triiodo-l-thyronine to the receptor, preventing MAPK activation and consequent actions downstream of MAPK. In vitro studies and a preliminary in vivo experiment indicate that tetrac blocks the action of thyroid hormone on tumor cell proliferation. Both unmodified tetrac and tetrac reformulated as a nanoparticle that does not gain access to the cell interior are under investigation in animal models as anticancer agents. Also under study is the susceptibility of other human cancer cell lines to induction of proliferation by physiological concentrations of thyroid hormone.
RESUMO
0.05),while that of serum P was significant(P
RESUMO
Objective:The study aims to investigate the expression of integrin ?V?3 and its relationship in gastric cancers.Methods:The tumoral and normal tissues were collected from 65 cases of gastric cancer patients and 40 controls.The clinical phasing and pathological staging of the patients were recorded,and immunohistochemical analysis was used to detect the expression of integrin ?V?3 and microvessel density(MVD)in gastric cancers.Results:The positive rate of integrin ?V?3 expression was significantly higher in gastric cancer tissues than normal mucosal tissues(72.38% vs 22.86%,?2=8.35,P=0.032).There was a significant difference in integrin ?V?3 expression or MVD between tumors of infiltrating and expanding growth patterns(?2=14.97,P=0.002;t=10.150,P=0.001,respectively),cancers in T3～T4 and T1～T2 stages(?2=15.21,P=0.015;t=5.961,P=0.001,respectively).The positive rate of integrin ?V?3 expression and MVD also showed corelationship with lymph node invasion and metastases.Conclusion:Tumoral expression of integrin?V?3 was closely related with biological behavior of gastric cancers,suggesting that detection of integrin ?V?3 expression may present a potential tool to evaluate the clinical and pathological staging,lymph node status and metastases.
RESUMO
Integrin ?V?3, one of the major members of the integrin family, plays a pivotal role in tumor angiogenesis because it mediates the cell-extracellular matrix and cell to cell adhesion as well as controls cells proliferation, differentiation, cellular modality and motility.Due to restricted high-expressions in tumors, integrin ?V?3, is considered a suitable targeting receptor for tumor diagnosis.In the past decade, several molecular imaging tracers for integrin ?V?3, have been used to noninvasively visualize its expression in tumor tissues and angiogenic blood vessels through the usage of nuclear imaging, nuclear magnetic resonance imaging, ultrasound, and optical imaging.Noninvasive detection of integrin ?V?3, expression can potentially be used for tumor diagnosis and prognosis.The current imaging probes used to target integrin ?V?3, through usage of different technologies are briefly recapitulated in this review.
RESUMO
Objective:To examine the expression of integrin ?V?3 in periodontium during experimental tooth movement, and then to propose the possible role of ?V?3 in bone remodeling during tooth movement. Methods:Thirty-five rabbits were divided into 7 groups (5 rabbits per group):untreated(control), 1,3, 5, 7, 14 and 21 d groups. A elastic coil spring was ligated between the incisors and the first molar and exert a force of approximately 0.78 N to pull the first molar mesially. The animals were sacrificed at each time intervals(1,3,5,7,14 and 21 d) respectively and specimens were made to observe the expression of integrin ?V?3 in periodontium through in situ hybridization. Results:Different extent expression of integrin ?V?3 were seen in osteoclasts, osteoblast precursors, osteoblasts,odontoclasts and odontoblast except bone cells. Conclusions: Integrin ?V?3 may play an important role in bone modeling, cementum resorption and its reparation during experimental tooth movement.
RESUMO
Objective To study the expression of endometrial integrin-? v? 3 in infertility patients induced by chronic pelvic inflammation disease(PID)and to analyze the correlation between the expression and the TCM syndrome patterns.Methods Twenty five infertility patients induced bychronic PID were enrolled into the experimental group,and 15 child-bearing aged women with normal reproductive capability were in the control group.The expression of integrin-? v? 3 in endometrium was measured by flow cytometry.The expression of integrin-? v? 3 in different TCM syndrome patterns was compared.Results The expression of integrin-? v? 3 was(4.76? 1.84)% in experimental group and(11.91? 1.04)% in the control group,there existed a significant difference(P
