Nuclear Expression of GS28 Protein: A Novel Biomarker that Predicts Prognosis in Colorectal Cancers
Abstract
Aims: GS28 (Golgi SNARE protein, 28 kDa), a member of the soluble N-ethylmaleimide-sensitive
factor attachment protein receptors (SNARE) protein family, plays a critical role in mammalian
endoplasmic reticulum (ER)-Golgi or intra-Golgi vesicle transport. To date, few researches on the
GS28 protein in human cancer tissues have been reported. In this study, we assessed the
prognostic value of GS28 in patients with colorectal cancer (CRC).
Methods and results: We screened for GS28 expression using immunohistochemistry in 230
surgical CRC specimens. The CRCs were right-sided and left-sided in 28.3% (65/230) and 71.3%
(164/230) of patients, respectively. GS28 staining results were available in 214 cases. Among these,
there were 26 nuclear predominant cases and 188 non-nuclear predominant cases. Stromal GS28
expression was noted in 152 cases of CRC. GS28 nuclear predominant immunoreactivity was
significantly associated with advanced tumour stage (p = 0.045) and marginally associated with
perineural invasion (p = 0.064). Decreased GS28 expression in the stromal cells was significantly
associated with lymph node metastasis (N stage; p = 0.036). GS28 expression was not associated
with epidermal growth factor receptor (EGFR) immunohistochemical positivity or KRAS mutation
status. Investigation of the prognostic value of GS28 with Kaplan-Meier analysis revealed a
correlation with overall survival (p = 0.004). Cases with GS28 nuclear predominant expression had
significantly poorer overall survival than those with a non-nuclear predominant pattern.
Conclusions: Taken together, these results indicate that GS28 nuclear predominant expression
could serve as a prognostic marker for CRC and may help in identifying aggressive forms of CRC