Overexpression of cytokine-induced apoptosis inhibitor 1 (CIAPIN1) contributes to multidrug resistance (MDR) in breast cancer. This study aimed to evaluate the potential of CIAPIN1 gene silencing by RNA interference (RNAi) as a treatment for drug-resistant breast cancer and to investigate the effect of CIAPIN1 on the drug resistance of breast cancer in vivo. We used lentivirus-vector-based RNAi to knock down CIAPIN1 in nude mice bearing MDR breast cancer tumors and found that lentivirus-vector-mediated silencing of CIAPIN1 could efficiently and significantly inhibit tumor growth when combined with chemotherapy in vivo. Furthermore, Western blot analysis showed that both CIAPIN1 and P-glycoprotein expression were efficiently downregulated, and P53 was upregulated, after RNAi. Therefore, we concluded that lentivirus-vector-mediated RNAi targeting of CIAPIN1 is a potential approach to reverse MDR of breast cancer. In addition, CIAPIN1 may participate in MDR of breast cancer by regulating P-glycoprotein and P53 expression.

ABSTRACT We report the case of a 45-year old woman with a painless soft tissue mass on the left side of her neck. At surgery, the lesion was solid and rubbery and revealed grey-white fibrous areas. It was pathologically confirmed as an elastofibroma, a rare, benign soft tissue tumour that is most commonly encountered in patients more than 55 years of age. Elastofibroma arising from connective tissue and usually found in the subscapular region is extremely rare in the neck. The pathogenesis of elastofibroma is still unclear but increased mechanical stress or nutritional derangement consequent to vascular involvement and hereditary factors may predispose to this lesion. Marginal excision is the treatment of choice in symptomatic patients.

RESUMEN Reportamos el caso de una mujer de 45 años con una masa de tejido suave sin dolor en el lado izquierdo del cuello. Al realizarse la cirugía, se halló que la lesión era sólida y gomosa, y presentaba áreas fibrosas de color gris-blanco. El análisis patológico confirmó que se trataba de un elastofibroma: un tumor del tejido blando, raro y benigno, que se encuentra más comúnmente en pacientes de más de 55 años de edad. Los elastofibromas que provienen del tejido conjuntivo y que generalmente se encuentran en la región subescapular, son extremadamente raros en el cuello. La patogénesis del elastofibroma no está todavía clara, pero el aumento del estrés mecánico o los desarreglos nutricionales consecuencia de problemas vasculares y factores hereditarios, pueden predisponer a esta lesión. La extirpación marginal es el tratamiento de elección en pacientes sintomáticos.