184P - Expression pattern of CDK12 protein in gastric cancer and its positive correlation with CD8+ cell density and CCL12 expression

Background

The aims of this study were to investigate the expression pattern of CDK12 protein in gastric cancer, and to analyze the correlation of CDK12 expression between CD8⁺ cell density.

Methods

Eighty-six paired tumor and non-tumor samples were collected from patients who underwent radical surgery and had pathological confirmed gastric adenocarcinoma. Immunohistochemistry was used to assess CDK12 expression and CD8⁺ cell density. Expression of CDK12 and CCL21 mRNA was detected by quantitative reverse transcription-polymerase chain reaction.

Results

CDK12 expression in gastric tumor tissues was significantly higher than those in paired non-tumor tissues (P < 0.001). High expression of CDK12 was identified in 43 cases (50%) which was significantly correlated with Lauren’s classification (diffuse type) and number of metastatic lymph nodes (≥15). High CDK12 protein level indicated a relative poorer overall survival of gastric cancer patients, while was not identified as an independent prognostic factor. Median number of CD8⁺ cells in tumor tissues was 51 (range: 0-292). Number of CD8⁺ cells was positively correlated with CDK12 expression score in tumor tissues (r = 0.243, P = 0.024). Positive correlation was also found between CDK12 and CCL21 mRNA expression (r = 0.419, P = 0.017).

Conclusions

High CDK12 expression was detected in gastric cancer which was correlated with malignant phenotypes and worse outcome. Positive correlations of CD8⁺ cell number and CCL21 mRNA expression with CDK12 level were identified.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Jun Ji.

Funding

The study was supported by National Science Foundation of China (81672327, 81802319 and 81602411) and Program of Shanghai Academic/Technology Research Leader (17XD1402600) and Program for Outstanding Medical Academic Leader and Shanghai Municipal Education Commission—Gaofeng Clinical Medicine Grant Support (20161410) and Development Grant for Clinical Trial (SHDC12017X06) and Science and Technology Comission of Shanghai Municipality (STCSM18411953000).

Disclosure

The author has declared no conflicts of interest.