ИСТИНА

Background & objectives. Cancer-associated fibroblasts (CAF) are cells with mesenchymal properties located in the tumor stroma. One of CAF`s marker is podoplanin (POD). Tumor budding (single cells are located in the invasive edge of the tumor) is an independent prognostic factor. Methods. We used Double Stain IHC Kit: M&R on human tissue (ab210058) with antibodies PCK (Dako, to identify buds) and POD (Abcam, as CAF marker) in 43 colorectal cancer. POD expression was evaluated by quantitative method (by color separation and half-counting of the area in the field of view in the LAS X program) in invasive region and around buds. Results. The aim was assessment of the density of CAF near the buds. POD around bud was negative in 30,4%, weak in 21,7%, moderate in 30,4% and significant (17,4%). A statistically significant relationship (p<0.01) was found between the level of POD around the tumor budding and its level in the invasive region. No significant differences in the density of CAF depending on the presence of the mucinous component, detected by the c2method(p=0.98). In most mucinous adenocarcinomas, a significant POD reaction was observed directly around the mucinous complexes and mucus lakes (p=0,85). We detected a relationship (p=0,023) between presence of buds and depth of tumor invasion(T), and on the presence of metastases(N). Conclusion. Using the duplex stain technology, the expression of POD around tumor budding was demonstrated for the first time, which allows us to judge the density of CAF. It was shown that the density of the POD expression around the tumor budding significantly corresponds to the reaction in the invasive region, which indicates that there is no need to evaluate it specifically around the tumor buds. For the first time, we described a more significant reaction near mucinous complexes.