14P - Comparative analysis of tumor ploidity and local immunity in gut cancer

Date 21 November 2014
Event ESMO Symposium on Immuno-Oncology 2014
Session Welcome reception and Poster viewing
Topics Gastric Cancer
Cancer Immunology and Immunotherapy
Presenter Oleg Kit
Authors O.I. Kit1, I. Novikova2, E. Zlatnik2, E. Nikipelova1, A. Bakhtin2, O. Selyutina2, A. Shaposhnikov3, Y. Gevorkyan4
  • 1Administration, Rostov Research Oncological Institute, 344037 - Rostov-on-Don/RU
  • 2Laboratory Of Immunophenotyping Of Tumors, Rostov Research Oncological Institute, 344037 - Rostov-on-Don/RU
  • 3Department Of Preventive Oncology, Rostov Research Oncological Institute, 344037 - Rostov-on-Don/RU
  • 4General Oncology, Rostov Research Oncological Institute, 344037 - Rostov-on-Don/RU

Abstract

Body

Background. The problem of local immunity in gut cancer patients is of great importance in both pathogenetic and prognostic aspects. The aim of the study was to assess factors of local cellular immunity in gut cancer patients with tumors of different ploidy. Aneuploid tumors are considered to have higher growth rates, poorer responses to treatment and more malignant courses of disease than diploid ones.

Methods. Samples of tissues: tumor (gut adenocarcinoma), peritumoral area and resection line were homogenized by BD Medimachine. Flow cytometer BD FACSCantoII (BD, USA) was used for DNA-cytometry (CycleTESTTMPLUS DNA Reagent Kit) and measurement of lymphocytè numbers (T-B-NK). The data were processed using program ModFit LT.

Results. The amount of aneuploid tumors was 55.6% (10 from 18) with 46.4 ± 6.1% of aneuploid tumor cells (25.5-82.7%). No statistically valid difference was found between lymphocyte contents of aneuploid and diploid tumors but it was revealed in tissues of peritumoral area and resection line. CD3+ cells level in peritumoral area of aneuploid tumors was higher than in diploid ones (65.1 ± 4.1 and 48.1 ± 5.7%, respectively; P < 0.05) as well as in resection line samples (65.7 ± 4.2 and 55.3 ± 3.1%, respectively; P < 0.05). Similar data were obtained for CD3 + CD4+ cells both in peritumoral area and resection line samples (27.4 ± 3.1 and 25.7 ± 1.7% in aneuploid tumors; 17.9 ± 2.1 and 15.0 ± 2.4% in diploid ones). Tissue content of CD3 + CD8+ and CD16/56+ lymphocytes in all the samples showed no dependence on tumor ploidy. On the contrary, B(CD19+)-cell numbers were found to be lower in all the samples of aneuploid tumors (16.5 ± 1.8 and 25.0 ± 3.6% in tumor tissue, 26.4 ± 2.9 and 42.6 ± 4.9 in peritumoral area; 20.1 ± 2.3 and 30.6 ± 2.5 in resection line tissue, respectively; P < 0,05)

Conclusions. Aneuploid tumors are characterized by a higher content of CD3+ and CD3 + CD4+ Т-lymphocytes in their peritumoral area and resection line as well as by lower percentage of B-cells. We consider that local prevalence of CD3 + CD4+ cells in gut tissue samples of patients with more malignant kind of adenocarcinoma may be due to Tregs.