[Expression of somatostatin receptor reporter gene and its correlation with targeted imaging in vivo for detection of pancreas carcinoma]

To evaluate the value of (99 m)Tc-sandostatin scintigraphy in targeted diagnosis of pancreas carcinoma and the correlation with expression of somatostatin receptor (SSTR) reporter gene in tumor tissue.Nude mice bearing human pancreas carcinoma xenograft were established in advance. (99 m)Tc-sandostatin imaging was performed in 18 nude mice and tumor to normal tissue ratio (T/NT) was calculated. mRNA expression of SSTR1, SSTR2 and SSTR5 in tumor tissue was detected by RT-PCR.Out of 18 nude mice, 13 mice showed intense uptake of (99 m)Tc-sandostatin. Six hours after (99 m)Tc-sandostatin administration, the T/NT ratio was 2.53 +/- 0.84. Five mice showed negative findings, and the T/NT ratio was 1.04 +/- 0.06. Positive correlations were obtained between the T/NT ratio and the expression of SSTR1 and SSTR2 mRNA, especially SSTR2 (r = 0.807, P0.01).High expression of SSTR1, SSTR2 and SSTR5 mRNA were found in human pancreas tumor xenograft in nude mice, especially SSTR2. There is a significant correlation between the tumor uptake of (99 m)Tc-sandostatin and SSTR2 mRNA level. This approach may allow SSTR-targeted diagnosis and therapy of human pancreas cancer.