Since colorectal cancer (CRC) remains one of the most common malignancies, a tremendous amount of studies keep taking place in this field. Over the past 25 years, a notable part of the scientific community has focused on the association between the immune system and colorectal cancer. A variety of studies have shown that high densities of infiltrating CD8+ T-cells are associated with improved disease-free and overall survival in CRC. Stromal cell-derived factor-1 (SDF-1) is a protein that regulates leukocyte trafficking and is variably expressed in several healthy and malignant tissues. There is strong evidence that SDF-1 has a negative prognostic impact on a variety of solid tumors. However, the existing data do not provide sufficient evidence that the expression of SDF-1 has an influence on CRC. Knowing nowadays, that the microenvironment plays a crucial role in the development of cancer, we hypothesized that the expression of SDF-1 in CRC could influence the prognostic significance of CD8+ T-cells, as an indicator of the essential role of the immune microenvironment in cancer development. Therefore, we explored the combined prognostic significance of CD8+ T-cell density and SDF-1 expression in a large CRC collective. We analyzed a tissue microarray of 613 patient specimens of primary CRCs by immunohistochemistry (IHC) for the CD8 + T-cells density and the expression of SDF-1 by tumor cells and tumor-infiltrating immune cells. Besides, we analyzed the expression of SDF-1 at the RNA level in The Cancer Genome Atlas cohort. We found that the combined high CD8+ T-cell infiltration and expression of SDF-1 shows a favorable 5-year overall survival rate (66%; 95% CI 48–79%) compared to tumors showing a high expression of CD8+ T-cell only (55%; 95% CI 45–64%; p = 0.0004). After stratifying the patients in nodal negative and positive groups, we found that the prognostic significance of CD8+ T-cell density in nodal positive colorectal cancer depends on SDF-1 expression. Univariate and multivariate Hazard Cox regression survival analysis considering the combination of both markers revealed that the combined high expression of SDF-1 and CD8+ T-cell density was an independent, favorable, prognostic marker for overall survival (HR = 0.34, 95% CI 0.17–0.66; p = 0.002 and HR = 0.45, 95% CI 0.23–0.89; p = 0.021, respectively). In our cohort there was a very weak correlation between SDF-1 and CD8+ T-cells (r_s = 0.13, p = 0.002) and in the trascriptomic expression of these two immune markers display a weak correlation (r_s = 0.28, p < 0.001) which was significantly more pronounced in stage III cancers (r_s = 0.40, p < 0.001). The combination of high CD8+ T-cell density and expression of SDF-1 represents an independent, favorable, prognostic condition in CRC, mostly in patients with stage III disease.

Background: Ovarian cancer (OC) is the most aggressive and fatal malignancy of the female reproductive system. Debulking surgery with adjuvant chemotherapy represents the standard treatment, but recurrence rates are particularly high. Over the past decades, the association between the immune system and cancer progression has been extensively investigated. However, the interaction between chemotherapy and cancer immune infiltration is still unclear. In this study, we examined the prognostic role of CD16 expression in OC, as related to the effectiveness of standard adjuvant chemotherapy treatment. Methods: We analyzed the infiltration by immune cells expressing CD16, a well-characterized natural killer (NK) and myeloid cell marker, in a tissue microarray (TMA) of 47 patient specimens of primary OCs and their matching recurrences by immunohistochemistry (IHC). We analyzed our data first in the whole cohort, then in the primary tumors, and finally in recurrences. We focused on recurrence-free survival (RFS), overall survival (OS), and chemosensitivity. Chemosensitivity was defined as RFS of more than 6 months. Results: There was no significant correlation between CD16 expression and prognosis in primary carcinomas. However, interestingly, a high density of CD16-expressing tumor-infiltrating immune cells (TICs) in recurrent carcinoma was associated with better RFS (p = 0.008) and OS (p = 0.029). Moreover, high CD16 cell density in recurrent ovarian carcinoma showed a significant association with chemosensitivity (p = 0.034). Univariate Cox regression analysis revealed that the high expression of CD16+ TIC in recurrent cancer biopsies is significantly associated with an increased RFS (HR = 0.49; 95% CI 0.24–0.99; p = 0.047) and OS (HR = 0.28; 95% CI 0.10–0.77; p = 0.013). However, this was not independent of known prognostic factors such as age, FIGO stage, resection status, and the number of chemotherapy cycles. Conclusions: The high density of CD16-expressing TICs in recurrent ovarian cancer is associated with a better RFS and OS, thereby suggesting a previously unsuspected interaction between standard OC chemotherapy and immune cell infiltration.

Objective: Colorectal cancer (CRC) remains the third most common cause of death from malignancies, while 30% of all these tumors develop in the rectum. The proximity of the rectum to vital structures, and in some cases the use of neoadjuvant treatment, make the surgical resection of this tumor a great challenge even for highly qualified surgeons. Understanding the mechanisms of rectal cancer (RC) development could lead to new concepts in the approach of diagnosis, prognosis, and eventually treatment of this disease. Despite the fact that TNM classification represents the gold standard tool for the staging of RC, a significant number of studies has recently focused on the association between the tumor microenvironment and RC. CD34 is a transmembrane phosphoglycoprotein expressed on human hematopoietic progenitor and vascular endothelial cells, as well in malignant tissues. It has also been shown to be involved in tumor invasion and angiogenesis. Because of the controversial data , we examined the expression of CD34 protein in RC specimens after stratifying the patients according to their UICC stage. Methods: In our retrospective study, we included 364 patients with unselected, clinically annotated primary RC specimens. We analyzed a tissue microarray (TMA) of these specimens by immunohistochemistry (IHC) for the expression of CD34 protein by tumor cells. Results: After stratifying the patients in nodal negative and positive groups, we found that the patients with Stage IIA tumors and high expression of CD34 protein had a favorable 5-year overall survival rate (53%; 95%CI = 40.0 – 65.1%) compared to tumors without expression of CD34 protein (26%; 95%CI = 10.7 – 44.6%, p = 0.003). Univariate and multivariate Hazard Cox regression survival analysis revealed that the combined the expression of CD34 protein was an independent, favorable, prognostic marker for overall survival in the stage IIA RC (HR = 0.39, 95%CI = 0.19 – 0.79; p = 0.009). Conclusion: Our data show that the expression of CD34 protein represents an independent, favorable, prognostic condition in nodal negative stage IIA RC. Thereby, we provide novel insights into the prognostic role of the tumor microenvironment in RC that might help in the development of novel treatment modalities by its modification.

Background: Since colorectal cancer (CRC) remains one of the most common malignancies, a tremendous amount of studies keep taking place in this field. Over the past 25 years, a notable part of the scientific community has focused on the association between the immune system and colorectal cancer. A variety of studies have shown that high densities of infiltrating CD8+ T cells are associated with improved disease-free and overall survival in colorectal cancer (CRC). Stromal cell-derived factor-1 (SDF-1) is a protein that regulates leukocyte trafficking and is variably expressed in several healthy and malignant tissues. There is strong evidence that SDF-1 has a negative prognostic impact on colorectal cancer (CRC). However, based on a significant correlation of SDF-1 and CD8+ T cells in a previous study (r=0.53, p<0.0001), we hypothesized that the prognostic significance of SDF-1 in CRC could depend on the immune microenvironment. Therefore, we explored the combined prognostic significance of SDF-1 expression and CD8+ T cell density in a large CRC collective. Methods: We analyzed a tissue microarray (TMA) of 613 patient specimens of primary CRCs by immunohistochemistry (IHC) for the expression of SDF-1 by tumor cells and tumor-infiltrating immune cells (TICs) and CD8+ T-cells. Besides, we analyzed the expression of SDF-1 at the RNA level in The Cancer Genome Atlas cohort (TCGA). Results: We found that the the combined high expression of SDF-1 and CD8+ T-cell infiltration shows a favorable 5-year overall survival rate (66%; 95%CI=48–79%) compared to tumors showing a high expression of CD8+ T-cells only (55%; 95%CI=45–64%; p=0.0004). High expression of SDF-1 and CD8+ T-cells infiltration was significantly associated with a favorable prognosis also in a validation group (p=0.016). Univariate and multivariate Hazard Cox regression survival analysis considering the combination of both markers revealed that the combined high expression of SDF-1 and CD8+ T cells was an independent, favorable, prognostic marker for overall survival (HR=0.34, 95%CI=0.17–0.66; p=0.002 and HR=0.45, 95%CI=0.23–0.89; p=0.021, respectively). In a spearman’s correlation analysis from the TCGA cohort, SDF-1 also correlated significantly with CD8+ T cells (r=0.28). Conclusions: SDF-1 high /CD8 high density represents an independent, favorable, prognostic condition in CRC, most likely due to an effective antigen-specific immune response.