Role and underlying mechanisms of the interstitial protein periostin in the diagnosis and treatment of malignant tumors.

Invasion and metastasis are the major characteristics of malignant tumors and are complex processes involving multiple genes. Gene regulation is a precise, large and complex biological control system, and its underlying mechanisms remain to be elucidated. Mesenchymal-specific genes are expressed primarily by mesenchymal cells, and the expression products of these genes are molecules with various structures and functions, including secreted proteins and extracellular matrix proteins. The periostin gene has been newly identified as a mesenchymal-specific gene and an extracellular-matrix secreted protein. Periostin is able to bind to various subtypes of integrin receptors on the surface of the cell membrane. This triggers relevant signal transduction pathways to alter the microenvironment of cancer cells in order to facilitate their survival, invasion, metastasis and angiogenesis as well as enhance the tolerance to hypoxia and chemicals. Therefore, periostin is associated with the grade of malignancy, level of invasion and prognosis of malignant tumors. The in-depth study of periostin may provide an effective marker for tumor diagnosis and prognosis, as well as a novel treatment target.

[Cochlear implantation with suprameatal approach in Chinese children].

OBJECTIVE: To investigate the technique of the suprameatal approach for cochlear implantation in Chinese profound sensory hearing loss children. METHODS: Suprameatal approach for cochlear implantation were used in 50 cases (total 53 ears) with profound sensory hearing loss from May 2005 to January 2007. The electrode was passed through the suprameatal tunnel and went between the incus and chorda tympani into the scala tympani. RESULTS: Electrodes were completely inserted in 51 ears. There were no postoperative complications in all cases. Although the long effect need to be observed, all cases received better hearing and speech development benefit from cochlear implantation in the follow-up period. Among the 50 cases, 26 had speech perception in the open condition; 18 patients could speak short sentences although not clearly; and 6 patients learned to speak individual words only. CONCLUSIONS: The suprameatal approach was found to be a simple and safe technique that does not need mastoidectomy and avoid endangering the facial nerve and the chorda tympani. It enables wide exposure of middle ear and is especially suitable for cases with narrow facial recess or anteriorly located facial nerve.