The mammalian peptide hormone stanniocalcin 2 (STC2) plays an oncogenic role in many human cancers. However, the exact function of STC2 in human head and neck squamous cell carcinoma (HNSCC) is unclear. We aimed to examine the function and clinical significance of STC2 in HNSCC. Using in vitro and in vivo assays, we show that overexpression of STC2 suppressed cell apoptosis, promoted cell proliferation, migration, invasion, and cell cycle arrest at the G1/S transition. By contrast, silencing of STC2 inhibited these activities. We further show that STC2 upregulated the phosphorylation of AKT and enhanced HNSCC metastasis via Snail-mediated increase of vimentin and decrease of E-cadherin. These responses were blocked by silencing of STC2/Snail expression or inhibition of pAKT activity. Furthermore, clinical data indicate that high STC2 expression was associated with high levels of pAKT and Snail in tumor samples from HNSCC patients with regional lymph node metastasis (P < 0.01). Thus, we conclude that STC2 controls HNSCC metastasis via the PI3K/AKT/Snail signaling axis and that targeted therapy against STC2 may be a novel strategy to effectively treat patients with metastatic HNSCC.

No abstract

In order to analyze the clinicopathological features of Chinese triple negative tumors, we performed a retrospective study of 1993 female unilateral breast cancer patients undergoing surgery in Cancer Hospital of Fudan University, Shanghai, China. Survival curves were performed with Kaplan-Meier method and annual recurrence hazard was estimated by hazard function. We observed that the rate of larger tumors in triple negative patients was higher than that in HR+/ERBB2- women, but lower than that in ERBB2+ subgroup (P = 0.0001). In addition, 21.83% of triple negative patients had four or more axillary lymph nodes involved as compared to 27.40% of ERBB2+ women and 22.75% of HR+/ERBB2- subgroup (P = 0.0056). In the survival analysis, we found a statistical significance for recurrence-free survival (RFS) among the three subgroups (P = 0.0037), with the rate of 72.89% for ERBB2+ patients, 78.40% for HR+/ERBB2- ones and 75.76% for triple negative ones at the 11th year respectively. When it came to hazard peaks, discrepancies existed in different subgroups. Similar to HR+/ERBB2- patients, triple negative subgroup showed an early major recurrence surge peaking at approximately year 2.5 as opposed to ERBB2+ counterparts with a tapering sharp at the 1st year. Furthermore, the first peak of triple negative tumors was higher than that of HR+/ERBB2- patients, but lower than that of ERBB2+ ones. Therefore, our findings suggested biological characteristics and prognostic outlook of Chinese triple negative breast cancers might be more favorable and somewhat different from those in Western populations.