The clinicopathological and prognostic impact of 14-3-3 sigma expression on vulvar squamous cell carcinomas

We investigated the 14-3-3σ expression in a series of 302 vulvar squamous cell carcinomas using immunohistochemistry and its associations with clinicopathological factors and clinical outcome.In cytoplasm, nucleus and cytoplasm/nucleus of vulvar carcinomas high 14-3-3σ protein expression was found in 72%, 59% and 75% of the carcinomas, respectively, and low levels in 28%, 41% and 25% of the cases, respectively. High level of 14-3-3σ in cytoplasm, nucleus and cytoplasm/nucleus was significantly correlated to large tumor diameter (p = 0.001, p = 0.002 and p = 0.001, respectively) and deep invasion (p = 0.01, p = 0.001 and p = 0.007, respectively). Variations of 14-3-3σ protein expression were not associated to disease-specific survival.Our results indicate that 14-3-3σ may be involved in the development of a subset of vulvar squamous cell carcinomas by down-regulation of 14-3-3σ protein. Neither cytoplasmic nor nuclear level of 14-3-3σ expression was associated with prognosis.Vulvar carcinoma represents 3–5% of all female genital cancer [1] and was previously considered a disease of elderly women. However, we see an increase in the incidence of vulvar carcinomas among younger women in recent years [2]. Considerable morbidity is often followed radical surgery, which has been the standard treatment [3]. Individualized therapy has been introduced to raise the quality of life for vulvar cancer patients [4]. Targeted therapy urge us to search for factors involved in tumorigenesis as well as identification of new tumor markers for therapy.In mammals, 14-3-3 proteins are composed of a highly conserved multigene family of small acidic proteins, including seven 14-3-3 isoforms (β, ε, γ, η, σ, τ, ζ) [5]. As a phosphoserine/phosphothreonine-binding protein, 14-3-3s bind to proteins within their RSXpSXP and RX(Y/F) XpSXP sequences (pS represents phosphoserine or phosphothreonine) [6] and thereby play an important role in various cellular processes such as altering enzymatic activ