A positive reaction for survivin in malignancy cell nuclei may condition their proliferative potential, which is associated with a higher risk of developing metastatic foci. (81.6%; 31/38) manifestation. The survivin nuclear manifestation was associated with tumor mass location and the presence of distant metastases (P=0.048 and P=0.026, respectively). Survivin was recognized in the sera of 38.2% (21/55) of CRC individuals and in 81.8% (18/22) of healthy individuals. Serum protein levels were found to correlate with hematocrit (P=0.035), hemoglobin (P=0.008) and albumin (P=0.045), but not with any of the investigated clinicopathological guidelines. The immunohistochemical positive reaction of survivin in the nuclei of malignancy cells may condition their proliferative capacity, which is associated with higher risk of developing metastatic foci. Therefore, the present study suggests that the manifestation of survivin may have diagnostic implications in cancer of the colon and thus requires further research. By contrast, the survivin serum level in CRC individuals appears to be diagnostically ineffectual for medical use. (15), and Choi and Chang (16), which mentioned the positive manifestation of survivin in 88.3 and 83.3% of CRC cases, respectively. Hernandez (17) confirmed the presence of this protein in 93% of individuals with colon cancer, while Xi (18) observed its manifestation in 60.7% of CRC individuals. Survivin offers different functions depending on its location. In the nucleus, the protein regulates cell growth, whereas its distribution to the DHBS cytoplasm determines the viability of malignancy cells (13). In the present study, the positive manifestation of survivin was more common in the cell DHBS cytoplasm (81.5% of cases) compared FLJ31945 with the cell nucleus (63.1% of cases) in the CRC individuals. Ponnelle (19) also used IHC and confirmed a higher incidence of positive survivin manifestation in the cytoplasm (41% of instances) compared with its localization in the nucleus (39%) of colon adenocarcinoma cells. The data are, however, inconsistent with the results published in studies by Shintani (20) and Qi (21), which found that positive survivin manifestation was more frequent in the nucleus than in the cytoplasm of malignancy cells in CRC individuals. Survivin mainly because an apoptotic protein may condition tumor aggressiveness and tumor cell invasiveness, including lymph node involvement and distant metastases (22). It has been demonstrated that survivin may determine, via different signaling pathways, the capacity of prostate and breast tumor cells to metastasize (22,23). Solitary studies have confirmed this potential of survivin in CRC DHBS individuals. Chu (24) and Xiaoyuan (25) observed a positive correlation between survivin overexpression and lymph node metastasis in CRC individuals. Furthermore, Shen (26) found that recombinant adenovirus reduced survivin manifestation and when linked with fluorouracil, clogged the malignancy cell metastasis of CRC. Lymph node involvement is associated with a poor prognosis in CRC individuals, since the risk of invasion into distant organs is improved. Li (27) mentioned the DHBS immunohistochemical reaction of survivin was associated with the presence of metastases and disease relapse in CRC individuals. Moreover, Lee (28) showed the positive manifestation of survivin was closely associated with main tumor and distant metastasis groups, and with tumor stage. The present detailed analysis exposed a positive correlation between survivin located in the nucleus of malignancy cells in CRC individuals and distant metastases and tumor location. The findings contradict those reported in the study by Qi (21), which mentioned that nuclear survivin manifestation was associated with a lower incidence of distant metastasis. Nuclear survivin location is responsible for cell cycle progression. It has been proven the nuclear overexpression of survivin increases the activity of cell growth and the passage of the cells to the S phase of the cell cycle, and results in a decrease in the percentage of the G0/G1 phase cells (29). The positive nuclear survivin manifestation in CRC cells appears to show the growth of tumor mitotic activity and increases the risk of developing metastatic foci, including those to distant organs. The serum level of survivin was measured in CRC individuals using ELISA in the present study. The protein was found.