Tissue detection of natural killer cells in colorectal adenocarcinoma.
BACKGROUND
Natural killer (NK) cells represent a first line of defence against a developing cancer; however, their exact role in colorectal cancer remains undetermined. The aim of the present study was to evaluate the expression of CD16 and CD57 [immunohistochemical markers of natural NK cells] in colorectal adenocarcinoma.


METHODS
Presence of NK cells was investigated in 82 colorectal adenocarcinomas. Immunohistochemical analysis was performed, using 2 monoclonal antibodies (anti-Fc Gamma Receptor II, CD16 and an equivalent to Leu-7, specific for CD-57). The number of immunopositive cells (%) was evaluated by image analysis. The cases were characterized according to: patient gender and age, tumor location, size, grade, bowel wall invasion, lymph node metastases and Dukes' stage.


RESULTS
NK cells were detected in 79/82 cases at the primary tumor site, 27/33 metastatic lymph nodes and 3/4 hepatic metastases; they were detected in levels similar to those reported in the literature, but their presence was not correlated to the clinical or pathological characteristics of the series, except for a negative association with the patients' age (p = 0.031).


CONCLUSIONS
Our data do not support an association of NK cell tissue presence with clinical or pathological variables of colorectal adenocarcinoma, except for a negative association with the patients' age; this might possibly be attributed to decreased adhesion molecule expression in older ages.
Papanikolaou
Ioannis S
IS
Department of Gastroenterology, H, Venizelou General Hospital, Faculty of Nursing, National University of Athens, Athens, Greece. ispapn@otenet.gr
Lazaris
Andreas C
AC
Apostolopoulos
Periklis
P
Kavantzas
Nikos
N
Papas
Maria G
MG
Mavrogiannis
Christos
C
Patsouris
Efstratios S
ES
Archimandritis
Athanasios
A
D000230:Adenocarcinoma / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018959:CD57 Antigens / Q000096:biosynthesis; D015179:Colorectal Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D007694:Killer Cells, Natural / Q000378:metabolism / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D017452:Receptors, IgG / Q000096:biosynthesis
D018959:CD57 Antigens; D017452:Receptors, IgG