Plasma levels of the proangiogenic protein CXCL16 remains elevated for 1 month after minimally invasive colorectal cancer resection

CXCL5 and CXCL14, but not CXCL16 as potential biomarkers of colorectal cancer

Experts emphasize that colorectal cancer (CRC) incidence and mortality are increasing. That is why its early detection is of the utmost importance. Patients with cancer diagnosed in earlier stages have a better prognosis and a chance for faster implementation of treatment. Consequently, it is vital to search for new parameters that could be useful in its diagnosis. Therefore, we evaluated the usefulness of CXCL5, CXCL14 and CXCL16 in serum of 115 participants (75 CRC patients and 40 healthy volunteers). Concentrations of all parameters were measured using Luminex. CRP (C-reactive protein) levels were determined by immunoturbidimetry, while levels of classical tumor markers were measured using CMIA (Chemiluminescence Microparticle Immunoassay). Concentrations of CXCL5 were statistically higher in the CRC group when compared to healthy controls. The diagnostic sensitivity, specificity, positive and negative predictive value, and area under the ROC curve (AUC) of CXCL5 and CXCL14 were higher than those of CA 19-9. Obtained results suggest the usefulness of CXCL5 and CXCL16 in the determination of distant metastases and differentiation between TNM (Tumor-Node-Metastasis) stages, as well as the usefulness of CXCL14 and CRP combination in CRC detection (primary or recurrence). However, further studies concerning their role in CRC progression are crucial to confirm and explain their diagnostic utility and clinical application as biomarkers.

Compared to preoperative plasma levels post-operative urokinase-type plasminogen activator-1 levels are persistently elevated for 6 weeks after minimally invasive colorectal resection

Background

Urokinase-type plasminogen activator-1 (uPA) is a serine protease that converts plasminogen to plasmin after binding to uPA receptor (uPAR). Plasmin catalyzes the regeneration of basement membrane, extracellular matrix, and other tissues. uPA alone and with plasmin leads to activation of angiogenic growth factors that impact tumor cell proliferation, adhesion, and migration. uPA over expression has been noted in colorectal cancer (CRC) and high tissue levels have been correlated with prognosis. uPA/uPAR promotes immune cell activation in healing surgical wounds and may alter perioperative uPA plasma levels. Postoperative (postop) plasma levels, if elevated, may impact the early growth of residual metastases. The impact of minimally invasive colorectal resection (MICR) surgery for CRC on plasma uPA levels is unknown. This study's aim was to measure plasma uPA levels during the first postop month.

Methods

CRC patients undergoing MICR who enrolled in an Institutional Review Board (IRB) approved data/plasma bank for whom adequate plasma was available were included in the study. Patients who had chemotherapy or radiotherapy within 4 weeks, those who received blood transfusions perioperatively and immunosuppressed patients were excluded. Clinical and pathological data were prospectively collected as were blood samples preoperatively, postop day (POD) 1, 3 and at least 1 late time point between POD 7-41. Plasma was isolated and stored at -80 ℃. Late samples were bundled into 7-day blocks and considered as single time points. Total uPA levels (ng/mL) were analyzed in duplicate via enzyme-linked immunosorbent assay (ELISA) and results reported as mean ± standard deviation (SD). The Wilcoxon paired t-test was used for analysis.

Results

Ninety-three patients undergoing MICR for CRC [colonic 68%; rectal 32%; average age 65.6 years, laparoscopic 63%, hand-assisted minimally invasive surgery (MIS) 37%] who met criteria were studied. Cancer stage breakdown was; stage I, 30%, stage II, 29%, stage III, 34%, stage IV, 7%. The median preoperative (preop) uPA plasma level (ng/mL) was 529.8 [95% confidence interval (CI): 462.8, 601.1] (n=93). Significant elevations in median levels vs. preop were present during POD 3 (542.8, 95% CI: 518.8, 597.3, n=86, P=0.003), POD 7-13 (688.1, 95% CI: 591.7, 753.0, n=72, P<0.001), POD 14-20 (764.9, 95% CI: 704.1, 911.6, n=27, P<0.001), POD 21-27 (685.6, 95% CI: 443.8, 835.8, n=15, P<0.001), and on POD 28-41 (800.3, 95% CI: 626.9, 940.6, n=21, P<0.001). The colon cancer subgroup's preop and POD 14-20 median results were significantly higher than the corresponding rectal cancer results; otherwise, at the other 5 postop time points there were no significant differences between the rectal and colon cancer subgroups. In addition, no association was found between cancer stage and preop uPA levels and no significant differences were found in postop uPA levels between the hand-assisted laparoscopic group and the lap assisted subgroup at any of the postop time points.

Conclusions

Persistently elevated plasma uPA levels at 5/6 postop time point (P<0.05), in combination with other previously demonstrated long duration proangiogenic plasma protein changes, may render the plasma proangiogenic within the period of the first month post-surgery and may promote angiogenesis within the residual tumor foci. The clinical significance pertaining to these changes, if any, is uncertain and remains to be proven.

Sustained postoperative plasma elevations of plasminogen activator inhibitor-1 following minimally invasive colorectal cancer resection

Plasminogen activator inhibitor-1 (PAI-1) is a serine protease inhibitor that inhibits urokinase-type plasminogen activator and tissue-type plasminogen activator. PAI-1 participates in angiogenesis, wound healing and tumor invasion, and additionally regulates endothelial cell proliferation, angiogenesis and tumor growth. The purpose of the present study was to measure plasma PAI-1 levels perioperatively in patients with colorectal cancer (CRC) undergoing minimally invasive colorectal resection (MICR). Patients with CRC who underwent elective MICR were eligible for the study. All patients were enrolled in an approved data/plasma bank. Patients with preoperative, postoperative day (POD) 1, POD 3, and at least one POD 7-34 plasma sample collection were studied. Plasma PAI-1 levels were determined in duplicate using ELISA, and the medians and 95% confidence intervals (CIs) were determined. The correlations between postoperative plasma PAI-1 levels and length of surgery were evaluated. PAI-1 levels were compared between patients who underwent laparoscopic-assisted vs. hand-assisted surgery. The preoperative PAI-1 levels of stage I, II, III and IV pathological stage subgroups were also compared. A total of 91 patients undergoing MICR for CRC were studied. The mean incision length was 8.0±3.9 cm, and the length of stay was 6.8±4.3 days. Compared with the median preoperative levels (17.30; 95% CI: 15.63-19.78 ng/ml), significantly elevated median levels were observed on POD 1 (28.86; 95% CI: 25.46-31.22 ng/ml; P<0.001), POD 3 (18.87; 95% CI: 17.05-21.78 ng/ml; P=0.0037), POD 7-13 (26.97; 95% CI: 22.81-28.74 ng/ml; P<0.001), POD 14-20 (25.92; 95% CI: 17.85-35.89 ng/ml; P=0.001) and POD 21-27 (22.63; 95% CI: 20.03-30.09 ng/ml; P<0.001). The PAI-1 levels in the hand-assisted group were higher compared with those in the laparoscopic-assisted group for 4 weeks after surgery; however, a significant difference was found only on POD 1. Therefore, plasma PIA-1 levels were found to be significantly elevated for 4 weeks after MICR, and the surgery-related acute inflammatory response may account for the early postoperative PIA-1 increase. Furthermore, PAI-1-associated VEGF-induced angiogenesis in the healing wounds may account for the late postoperative elevations, and increased PAI-1 levels may promote angiogenesis in residual tumor deposits.

Plasma Levels of Keratinocyte Growth Factor Are Significantly Elevated for 5 Weeks After Minimally Invasive Colorectal Resection Which May Promote Cancer Recurrence and Metastasis

Background: Human Keratinocyte Growth Factor (KGF) is an FGF family protein produced by mesenchymal cells. KGF promotes epithelial cell proliferation, plays a role in wound healing and may also support tumor growth. It is expressed by some colorectal cancers (CRC). Surgery's impact on KGF levels is unknown. This study's purpose was to assess plasma KGF levels before and after minimally invasive colorectal resection (MICR) for CRC. Aim: To determine plasma KGF levels before and after minimally invasive colorectal resection surgery for cancer pathology. Method: CRC MICR patients (pts) in an IRB approved data/plasma bank were studied. Pre-operative (pre-op) and post-operative (post-op) plasma samples were taken/stored. Late samples were bundled into 7 day blocks and considered as single time points. KGF levels (pg/ml) were measured via ELISA (mean ± SD). The Wilcoxon paired t-test was used for statistical analysis. Results: Eighty MICR CRC patients (colon 61%; rectal 39%; mean age 65.8 ± 13.3) were studied. The mean incision length was 8.37 ± 3.9 and mean LOS 6.5 ± 2.6 days. The cancer stage breakdown was; I (23), II (26), III (27), and IV (4). The median pre-op KGF level was 17.1 (95 %CI: 14.6-19.4; n = 80); significantly elevated (p < 0.05) median levels (pg/ml) were noted on post-op day (POD) 1 (23.4 pg/ml; 95% CI: 21.4-25.9; n = 80), POD 3 (22.5 pg/ml; 95% CI: 20.7-25.9; n = 76), POD 7-13 (21.8 pg/ml; 95% CI: 17.7-25.4; n = 50), POD 14-20 (20.1 pg/ml; 95% CI: 17.1-23.9; n = 33), POD 21-27 (19.6 pg/ml; 95% CI: 15.2-24.9; n = 15) and on POD 28-34 (16.7 pg/ml; 95% CI: 14.0-25.8; n = 12). Conclusion: Plasma KGF levels were significantly elevated for 5 weeks after MICR for CRC. The etiology of these changes is unclear, surgical trauma related acute inflammatory response and wound healing process may play a role. These changes, may stimulate angiogenesis in residual tumor deposits after surgery.

CXC chemokine ligand 16: a Swiss army knife chemokine in cancer

Today, cancer is one of the leading causes of death worldwide. Lately, cytokine and chemokine imbalances have gained attention amongst different involved pathways in cancer development and attracted much consideration in cancer research. CXCL16, as a member of the CXC subgroup of chemokines, has been attributed to be responsible for immune cell infiltration into the tumour microenvironment. The aberrant expression of CXCL16 has been observed in various cancers. This chemokine has been shown to play a conflicting role in tumour development through inducing pro-inflammatory conditions. The infiltration of various immune and non-immune cells such as lymphocytes, cancer-associated fibroblasts and myeloid-derived suppressor cells by CXCL16 into the tumour microenvironment has complicated the tumour fate. Given this diverse role of CXCL16 in cancer, a better understanding of its function might build-up our knowledge about tumour biology. Hence, this study aimed to review the impact of CXCL16 in cancer and explored its therapeutic application. Consideration of these findings might provide opportunities to achieve novel approaches in cancer treatment and its prognosis.