Marie Lequoy1,2, Christèle Desbois-Mouthon2, Dominique Wendum2,3, Vandana Gupta4, Jean-Luc Blachon5, Olivier Scatton2,6, Sylvie Dumont2,3, Mireille Bonnemaire5, Fabien Schmidlin5, Olivier Rosmorduc2,7, Laetitia Fartoux2,7. 1. Department of Hepatology, AP-HP, Saint-Antoine Hospital, Paris, France. 2. Saint-Antoine Research Centre, Sorbonne Universités, UPMC Univ. Paris 06, UMR_S 938, Paris, France. 3. Department of Pathology, AP-HP, Saint-Antoine Hospital, Paris, France. 4. Oncology and Biomarkers, Ipsen Biosci. Inc., Cambridge, MA, USA. 5. Ipsen Innovation, R&D, Les Ulis, France. 6. Department of Hepatobiliary Surgery, AP-HP, Pitié Salpêtrière Hospital, Paris, France. 7. Department of Hepatology, AP-HP, Pitié Salpêtrière Hospital, Paris, France.
Abstract
AIMS: To investigate the status of somatostatin receptors (SSTRs) in resected hepatocellular carcinoma (HCC). METHODS AND RESULTS: Transcript and protein levels of SSTR2, SSTR3 and SSTR5 were investigated, with real-time polymerase chain reaction (PCR) and manual and automated immunohistochemistry (IHC), in 53 resected HCCs and paired non-tumour tissues. SSTR1, SSTR4, SSTR5TMD4 and SSTR5TMD5 were analysed with real-time PCR. SSTR3 and SSTR5 transcripts were expressed in ~25% of HCCs, but not in adjacent non-tumour tissues. SSTR1 and SSTR2 transcripts were overexpressed in 42% and 32% of HCCs, respectively. SSTR4, SSTR5TMD4 and SSTR5TMD5 were not detected. Membrane staining for SSTR2 was detected in 38% of HCCs, whereas SSTR5 protein was detectable in only 11% of HCCs. SSTR3 protein was detected in the majority of HCCs and adjacent non-tumour liver tissues, but membrane staining was <20% of that in HCCs. The results obtained with the two IHC methods were highly correlated (P < 0.0001). Statistical analyses also showed a positive correlation between SSTR2 membrane staining and cytokeratin 19 expression (P = 0.04), serum α-fetoprotein level (P = 0.002), and poor differentiation (P = 0.05). CONCLUSIONS: Membrane SSTR2 is detected reliably in HCCs by IHC, and is a potential therapeutic target, as it is coexpressed with markers of poor prognosis.
AIMS: To investigate the status of somatostatin receptors (SSTRs) in resected hepatocellular carcinoma (HCC). METHODS AND RESULTS: Transcript and protein levels of SSTR2, SSTR3 and SSTR5 were investigated, with real-time polymerase chain reaction (PCR) and manual and automated immunohistochemistry (IHC), in 53 resected HCCs and paired non-tumour tissues. SSTR1, SSTR4, SSTR5TMD4 and SSTR5TMD5 were analysed with real-time PCR. SSTR3 and SSTR5 transcripts were expressed in ~25% of HCCs, but not in adjacent non-tumour tissues. SSTR1 and SSTR2 transcripts were overexpressed in 42% and 32% of HCCs, respectively. SSTR4, SSTR5TMD4 and SSTR5TMD5 were not detected. Membrane staining for SSTR2 was detected in 38% of HCCs, whereas SSTR5 protein was detectable in only 11% of HCCs. SSTR3 protein was detected in the majority of HCCs and adjacent non-tumour liver tissues, but membrane staining was <20% of that in HCCs. The results obtained with the two IHC methods were highly correlated (P < 0.0001). Statistical analyses also showed a positive correlation between SSTR2 membrane staining and cytokeratin 19 expression (P = 0.04), serum α-fetoprotein level (P = 0.002), and poor differentiation (P = 0.05). CONCLUSIONS: Membrane SSTR2 is detected reliably in HCCs by IHC, and is a potential therapeutic target, as it is coexpressed with markers of poor prognosis.