STIM1 overexpression in CRC was significantly connected with tumor size, depth of invasion, lymphnode metastasis status and serum levels of carcinoembryonic antigen
STIM1 overexpression in CRC was significantly connected with tumor size, depth of invasion, lymphnode metastasis status and serum levels of carcinoembryonic antigen. a role for COX-2 in STIM1-mediated CRC metastasis. Our studies also suggested a new approach to inhibit STIM1-mediated metastasis with COX-2 inhibitors. value was calculated by two-tailed Fishers exact test. OR and CI in C refer to Odds Ratio and Confidence Interval, respectively. To further investigate the role of STIM1 in CRC progression and metastasis, we examined the expression levels of STIM1 in a cohort of 38 CRC patients treated at the Kaohsiung Medical University Hospital with a different approach (Table 1). Tumor tissues and paired adjacent normal tissues were collected from these patients according to an IRB approved protocol. Total mRNA from these samples was extracted and STIM1 expression levels in these samples were evaluated using quantitative real time PCR (qRT-PCR). As shown in Physique 2A, STIM1 expression levels in tumors were elevated in 19 out of the 38 CRC patients when compared to the paired adjacent normal tissue. We further used ELISA to compare the protein expression levels of STIM1 in another 20 paired CRC specimens and adjacent normal tissue. STIM1 protein levels increased in 90% of CRC samples (18 out of 20), suggesting the hyperactivation Dabrafenib (GSK2118436A) of store-operated Dabrafenib (GSK2118436A) calcium entry in CRC patients (supplementary Physique 1). To investigate the clinical significance of STIM1 overexpression in CRC progression, we studied the relationship between STIM1 expression levels and the clinicopathological data from CRC patients. As shown in Table 1, there TF were statistically significant correlation between STIM1 expression levels and the tumor size, depth of tumor invasion, lymph node metastasis status and UICC stages of CRC. The percentage of CRC samples with high STIM1 expression levels more than doubled in tumors equal or more than 5cm (68.6%) when compared to the less than 5cm group (31.6%) (Table 1, Fig. 2B). Intriguingly, all the 19 CRC cases with STIM1 overexpression had deep invasion (T3 and T4): either invasion completely through the muscularis propria into the serosa layer (T3) or in some cases had produced through the colon wall and invaded other organs or tissues (T4); no STIM1 overexpression was detected in the 5 CRC cases with shallower invasion (T1 and T2) (Table 1, Fig. 2C). Consistent with our IHC staining results (Physique 1), 65.2% of lymph node metastasis positive CRC patients also had high STIM1 levels; in contrast, STIM1 overexpression was only detected in 26.7% of lymph node negative patients. (Table 1, Fig. 2D). Patients with high levels of STIM1 expression were about twice as likely to develop metastasis (15 out of a total of 19 cases) as patients with low STIM1 levels (8 out of 19) (Table 1, Fig. 2D). Open in a separate window Physique 2 The correlation between STIM1 overexpression and tumor size, depth of invasion, lymphnode metastasis in a cohort of colorectal cancer patientsA, 38 colon cancer patients RNA was isolated from tumor and normal tissues around the cancer tissue. Real-time PCR was applied to detect STIM1 gene expression levels. STIM1 gene expression levels in CRC tumor tissue was compared with paired normal adjacent colon tissues. Threshold of relative of STIM1 gene expression is set as 1. The Dabrafenib (GSK2118436A) patient is usually define as STIM1 high when the ratio is larger than one, and STIM1 low when the ratio equals or is lower than 1. * Dabrafenib (GSK2118436A) Indicatess relative of STIM1 high patients. BCD, The association between STIM1 expression levels and tumor size, invasion depth and lymphnode metastasis. values were calculated by two-tailed Fishers exact test. E, Pearson correlation between STIM1 expression ratios and preoperative serum CEA in CRC patients. Table 1 Correlations between clinicpathological features and gene expression for 38 postoperative colorectal cancer patients value of less than 0. 05 was considered statistically significant. aInternational Union Against Cancer. bWD: Well differentiated; MD: Moderately well differentiated; PD: Poorly differentiated. ?Adjusted the effects of age, sex and location (colon and rectum). When analyzed with multivariate analysis, the correlation between STIM1 expression levels and lymph node metastasis and tumor stages showed borderline significance (p=0.0527 and 0.08, respectively) (supplementary Table 1). Collectively, our data indicated STIM1 might promote CRC progression by mediating tumor.