Somatostatin receptor subtype 2 A (SSTR2A) and HER2 expression in gastric adenocarcinoma.
BACKGROUND
A possible anticancer role for somatostatin has been suggested. This study assessed the presence of somatostatin receptor subtype 2A (SSTR2A) in gastric cancer, correlating its expression with histological type, grade, human epidermal growth factor receptor 2 (HER2) expression, and disease outcome.


METHODS
Gastric cancer tissues of 51 consecutive patients were collected for immunohistochemical assessment of both SSTR2A and HER2 expression.


RESULTS
SSTR2A expression was observed in 38 (74.5%) cases. Prevalence of SSTR2A expression was significantly higher in well to moderately (G1-2) differentiated gastric cancer as compared to poorly (G3) differentiated tumors (96% vs. 52%; p<0.01), as well as in intestinal- than in diffuse-type cancer (97% vs. 20%; p<0.001). HER2 expression was positive in 18 (35%) patients, and it was associated with SSTR2A expression (r=0.50, p<0.001), being co-expressed in 17 (95%) out of 18 positive cases. RFS was significantly lower in patients with diffuse HER2 expression.


CONCLUSIONS
This study demonstrated a co-localization between SSTR2A and HER2, potentially opening new therapeutic strategies for patients with gastric cancer.
Department of Oncology, Sant'Andrea Hospital, La Sapienza University, via Grottarossa 1035, 00189, Rome, Italy. adriana.romiti@tin.it
Adriana
A
Romiti
Roberta
R
Di Rocco
Massimo
M
Milione
Luigi
L
Ruco
Vincenzo
V
Ziparo
Angelo
A
Zullo
Enrico
E
Duranti
Ida
I
Sarcina
Viola
V
Barucca
Chiara
C
D'Antonio
Paolo
P
Marchetti
D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D017481:Receptors, Somatostatin / Q000378:metabolism*; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000473:pathology
D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases; D017481:Receptors, Somatostatin; C093733:somatostatin receptor 2; C508053:ERBB2 protein, human