Perioperative GMCSF limits the proangiogenic plasma protein changes associated with colorectal cancer resection

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.

Potential impact of invasive surgical procedures on primary tumor growth and metastasis

Surgical procedures such as tumor resection and biopsy are still the gold standard for diagnosis and (determination of) treatment of solid tumors, and are prognostically beneficial for patients. However, growing evidence suggests that even a minor surgical trauma can influence several (patho) physiological processes that might promote postoperative metastatic spread and tumor recurrence. Local effects include tumor seeding and a wound healing response that can promote tumor cell migration, proliferation, differentiation, extracellular matrix remodeling, angiogenesis and extravasation. In addition, local and systemic immunosuppression impairs antitumor immunity and contributes to tumor cell survival. Surgical manipulation of the tumor can result in cancer cell release into the circulation, thus increasing the chance of tumor cell dissemination. To prevent these undesired effects of surgical interventions, therapeutic strategies targeting immune response exacerbation or alteration have been proposed. This review summarizes the current literature regarding these local, systemic and secondary site effects of surgical interventions on tumor progression and dissemination, and discusses studies that aimed to identify potential therapeutic approaches to prevent these effects in order to further increase the clinical benefit from surgical procedures.

Assessment of perioperative stress in colorectal cancer by use of in vitro cell models: a systematic review

Background

The perioperative period is important for patient outcome. Colorectal cancer surgery can lead to metastatic disease due to release of disseminated tumor cells and the induction of surgical stress response. To explore the overall effects on surgically-induced changes in serum composition, in vitro model systems are useful.

Methods

A systematic search in PubMed and EMBASE was performed to identify studies describing in vitro models used to investigate cancer cell growth/proliferation, cell migration, cell invasion and cell death of serum taken pre- and postoperatively from patients undergoing colorectal tumor resection.

Results

Two authors (MG and TK) independently reviewed 984 studies and identified five studies, which fulfilled the inclusion criteria. Disagreements were solved by discussion. All studies investigated cell proliferation and cell invasion, whereas three studies investigated cell migration, and only one study investigated cell death/apoptosis. One study investigated postoperative peritoneal infection due to anastomotic leak, one study investigated mode of anesthesia (general anesthesia with volatile or intravenous anesthetics), and one study investigated preoperative intervention with granulocyte macrophage colony stimulating factor (GMCSF). In all studies an increased proliferation, cell migration and invasion was demonstrated after surgery. Anesthetics with propofol and intervention with GMCSF significantly reduced postoperative cell proliferation, whereas peritoneal infection enhanced the invasive capability of tumor cells.

Conclusion

This study suggests that in vitro cell models are useful and reliable tools to explore the effect of surgery on colorectal cancer cell proliferation and metastatic ability. The models should therefore be considered as additional tests to investigate the effects of perioperative interventions.

Plasma monocyte chemotactic protein-1 remains elevated after minimally invasive colorectal cancer resection

AIM: To investigate plasma Monocyte Chemotactic Protein-1 levels preoperatively in colorectal cancer (CRC) and benign patients and postoperatively after CRC resection.

METHODS: A plasma bank was screened for minimally invasive colorectal cancer resection (MICR) for CRC and benign disease (BEN) patients for whom preoperative, early postoperative, and 1 or more late postoperative samples (postoperative day 7-27) were available. Monocyte chemotactic protein-1 (MCP-1) levels (pg/mL) were determined via enzyme linked immuno-absorbent assay.

RESULTS: One hundred and two CRC and 86 BEN patients were studied. The CRC patient’s median preoperative MCP-1 level (283.1, CI: 256.0, 294.3) was higher than the BEN group level (227.5, CI: 200.2, 245.2; P = 0.0004). Vs CRC preoperative levels, elevated MCP-1 plasma levels were found on postoperative day 1 (446.3, CI: 418.0, 520.1), postoperative day 3 (342.7, CI: 320.4, 377.4), postoperative day 7-13 (326.5, CI: 299.4, 354.1), postoperative day 14-20 (361.6, CI: 287.8, 407.9), and postoperative day 21-27 (318.1, CI: 287.2, 371.6; P < 0.001 for all).

CONCLUSION: Preoperative MCP-1 levels were higher in CRC patients (vs BEN). After MICR for CRC, MCP-1 levels were elevated for 1 mo and may promote angiogenesis, cancer recurrence and metastasis.

Minimally invasive colorectal resection is associated with significantly elevated levels of plasma matrix metalloproteinase 3 (MMP-3) during the first month after surgery which may promote the growth of residual metastases

INTRODUCTION

MMP-3, a member of the matrix metalloproteinase (MMP) family, is involved in the breakdown of the extracellular matrix in tissue remodeling and may also play a role in cancer progression and metastasis. Minimally invasive colorectal resection (MICR) may increase plasma MMP-3 levels directly via surgical trauma or indirectly due to surgery-associated elevations in TNF-α and IL1 which are regulators of MMP-3. This study's purpose was to evaluate plasma MMP-3 levels during the first month after MICR for colorectal cancer.

METHODS

Patients enrolled in an IRB approved data/plasma bank who underwent elective MICR for CRC. Blood plasma samples had been collected preoperatively, on postoperative day (POD) 1, 3 and at varying postoperative time points and were stored at -80 °C. The late samples (POD 7-41) were bundled into 7 day time blocks and considered as single time points. MMP-3 levels were analyzed in duplicate via ELISA and the results reported as mean ± SD. The paired t test was used for analysis (significance, p < 0.008 after Bonferroni's correction).

RESULTS

A total of 73 CRC patients who underwent MICR met the inclusion criteria. The mean PreOp MMP-3 level was 14.9 ± 7.8 ng/ml (n = 73). Significantly elevated mean plasma levels were noted on POD 1 (21.4 ± 14.7 ng/ml, n = 73, p < 0.0001), POD 3 (37.9 ± 21.5 ng/ml, n = 72, p < 0.0001), POD 7-13 (22.0 ± 13.0 ng/ml, n = 56, p < 0.0001), POD 14-20 (21.9 ± 10.3 ng/ml, n = 20, p = 0.003), and on POD 21-27 (21.9 ± 11.43 ng/ml, n = 20, p = 0.002) when compared to PreOp levels. Plasma levels returned to the PreOp baseline at the POD 28-41 time point (n = 16, p = 0.07).

CONCLUSION

Plasma MMP-3 levels remained significantly elevated from baseline for 4 weeks after MICR for CRC. The early postoperative increase in MMP-3 levels may be due to the surgery-related acute inflammatory response; the elevation noted during weeks 2-3 may be related to wound healing. Increased MMP-3 levels may promote metastases or the growth of residual cancer.

Minimally invasive colorectal resection for benign pathology is associated with persistent proangiogenic plasma compositional changes

BACKGROUND

Minimally invasive colorectal resection for cancer is associated with increased plasma levels of numerous proangiogenic proteins for 3 to 4 weeks postoperatively, and plasma from postoperative weeks 2 and 3 stimulates proangiogenic endothelial cell behavior in vitro. It is unknown if similar plasma changes occur after minimally invasive colorectal resection for benign pathology.

OBJECTIVE

The aim of this study is to assess 1) plasma levels of angiopoetin-2, placental growth factor, and soluble vascular cell adhesion molecule-1 after minimally invasive colorectal resection for benign pathology and 2) postoperative plasma's effects on in vitro endothelial cell proliferation (branch point formation), migration, and invasion.

DESIGN

Prospectively gathered plasma samples taken from patients undergoing colorectal resection who consented to participate in an institutional review board-approved plasma and data bank were used for ELISAs and in vitro endothelial cell studies.

SETTINGS

The plasma and clinical data used were collected at 3 hospitals.

PATIENTS

Patients undergoing minimally invasive colorectal resection for benign indications who were enrolled in a plasma/data bank and for whom adequate samples and volumes of plasma were available were included in the study.

MAIN OUTCOME MEASURES

Perioperative plasma levels of angiopoetin-2, placental growth factor, and soluble vascular cell adhesion molecule-1 were the primary outcomes measured. In vitro rates of endothelial cell branch point formation, migration, and invasion were determined after the addition of preoperative and postoperative plasma samples to endothelial cell cultures.

RESULTS

Plasma from 86 patients undergoing minimally invasive colorectal resection for benign indications was assessed (diverticulitis, 30; benign polyps, 56). Plasma levels of angiopoetin-2, placental growth factor, and soluble vascular cell adhesion molecule-1 were significantly increased for 3 to 4 weeks postoperatively compared with preoperative levels. In regard to the endothelial cell culture assays, significantly increased endothelial cell branch point formation, invasion, and migration results were noted with plasma from the second and third weeks postoperatively in comparison with preoperative culture results.

LIMITATIONS

The weaknesses of this study are the limited numbers of late postoperative plasma samples and the need to bundle late samples into 7- to 12-day time blocks.

CONCLUSIONS

Minimally invasive colorectal resection for benign pathology is associated with persistent proangiogenic plasma alterations similar to those found in patients who have cancer. Surgical trauma and not the indication is the likely cause.

Plasma from the second and third weeks after open colorectal resection for cancer stimulates in vitro endothelial cell growth, migration, and invasion

INTRODUCTION

Angiogenesis is central to wound healing and tumor growth. Postoperative (postop) plasma from weeks 2 and 3 after minimally invasive colorectal resection (MICR) stimulates endothelial cell (EC) migration (MIG), invasion (INV), and proliferation (all vital to angiogenesis) compared with preoperative (preop) plasma results and may promote postop tumor growth. The purpose of this study was to determine whether plasma from open colorectal resection (OCR) patients has similar proangiogenic EC effects in vitro.

METHODS

OCR cancer patient plasma from institutional review board-approved banks was used; patients with preop and one postop sample from postoperative days (POD) 7-33 were eligible. Samples were bundled into 7- to 13-day periods and considered as single time points. In vitro cultures of human umbilical venous ECs were used for the EC proliferation (BPF, Branch Point Formation), INV, and MIG assays performed with preop, POD 7-13, POD 14-20, and POD 21-33 plasma. Data were analyzed by paired t test and were reported as mean ± standard deviation (significance, P < 0.05).

RESULTS

Plasma from 53 cancer patients (25 rectal and 28 colon) was used. Because of limited postop samples, the number for each time point varies: POD 7-13, n = 30; POD 14-20, n = 26; and POD 21-33, n = 17. In vitro EC BPF was significantly greater at the POD 7-13 (P < 0.0001) and POD 14-20 (P < 0.0001) time points versus preop results. Significantly greater EC INV and MIG were noted on POD 7-13 and POD 14-20 versus the preop plasma results (P < 0.0001). In regards to POD 21-33, a significantly greater result was noted only for the INV assay versus preop.

CONCLUSIONS

Plasma from weeks 2 and 3 after OCR stimulates in vitro EC BPF, INV, and MIG. A significant difference from preop baseline was noted only for the INV assay in week 4. The OCR and previous MICR results were largely similar. Tumor angiogenesis may be stimulated after OCR and MICR for 3 weeks. Further studies are warranted.

Minimally invasive colorectal resection is associated with a transient increase in plasma hepatocyte growth factor levels early after surgery for colon cancer

INTRODUCTION

Surgery's impact on blood levels of hepatocyte growth factor (HGF), a potent angiogenic factor, is unknown. Preoperative (PreOp) HGF blood levels are elevated in patients with colorectal cancer (CRC) and correlate with disease stage and prognosis. This study's purpose was to determine plasma HGF levels after minimally invasive colorectal resection (MICR) in patients with CRC.

METHODS

Clinical and operative data were collected. Blood samples were obtained in all patients PreOp and on postoperative day (POD) 1 and 3; in some, samples were taken during weeks 2 and 3 after MICR. Late samples were bundled into 7-day time blocks. HGF levels were determined via enzyme-linked immunosorbent assay in duplicate. Student's t test was used to analyze the data (significance, P < .0125 after Bonferroni correction).

RESULTS

A total of 28 CRC patients who underwent MICR were studied. Most had right, sigmoid, or left segmental colectomy. The mean plasma HGF level was higher on POD 1 (2417 ± 1476 pg/mL, P < .001) and POD 3 (2081 ± 1048 pg/mL, P < .001) when compared with PreOp levels (1045 ± 406 pg/mL). Plasma levels were back to baseline by the second (1100 ± 474 pg/mL, P = .64) and third postoperative weeks (1010 ± 327 pg/mL, P = .51).

CONCLUSION

MICR for CRC is associated with a 1.9- to 2.3-fold increase in plasma HGF levels during the first 3 PODs after which levels normalize. This transient increase may briefly promote angiogenesis and the growth of residual tumor cells.

Plasma levels of angiostatin and endostatin remain unchanged for the first 3 weeks after colorectal cancer surgery

INTRODUCTION

Angiostatin and endostatin are endogenous inhibitors of angiogenesis with anticancer effects. After minimally invasive colorectal resection (MICR), blood levels of the proangiogenic factors vascular endothelial growth factor (VEGF) and angiopoetin 2 (Ang-2) are elevated for 2-4 weeks. Also, postoperative human plasma from weeks 2 and 3 after MICR has been shown to stimulate endothelial cell proliferation and migration, which are critical to angiogenesis. This proangiogenic state may stimulate tumor growth early after MICR. Surgery's impact on angiostatin and endostatin is unknown. This study's purpose is to determine perioperative plasma levels of these two proteins in colorectal cancer (CRC) patients undergoing MICR.

METHODS

Endostatin levels were assessed in 34 CRC patients and angiostatin levels in 30 CRC patients. Blood samples were taken preoperatively and on postoperative day (POD) 1 and 3 in all patients; in a subset, samples were taken between POD 7 and 20. The late samples were bundled into 7-day blocks (POD 7-13, POD 14-20) and considered as single time points. Angiostatin and endostatin plasma levels were determined via enzyme-linked immunosorbent assay (ELISA) in duplicate. Wilcoxon signed-rank test and Student's t test were used to analyze endostatin and angiostatin data, respectively. Significance was set at P<0.0125 (after Bonferroni correction).

RESULTS

There was a significant decrease in median plasma endostatin levels on POD 1, which returned to the preoperative level by POD 3. There was no significant difference between pre- and postoperative plasma angiostatin levels.

CONCLUSIONS

MICR has a very transient impact on plasma levels of endostatin and no impact on angiostatin during the first 21 days following surgery. Thus, angiostatin and endostatin do not likely contribute to or inhibit the persistent proangiogenic changes noted after MICR.

The perioperative period is an underutilized window of therapeutic opportunity in patients with colorectal cancer

OBJECTIVE

In this review, we address the underlying mechanisms by which surgery augments metastases outgrowth and how these insights can be used to develop perioperative therapeutic strategies for prevention of tumor recurrence.

SUMMARY BACKGROUND DATA

Surgical removal of the primary tumor provides the best chance of long-term disease-free survival for patients with colorectal cancer (CRC). Unfortunately, a significant part of CRC patients will develop metastases, even after successful resection of the primary tumor. Paradoxically, it is now becoming clear that surgery itself contributes to development of both local recurrences and distant metastases.

METHODS

Data for this review were identified by searches of PubMed and references from relevant articles using the search terms "surgery," "CRC," and "metastases."

RESULTS

Surgical trauma and concomitant wound-healing processes induce local and systemic changes, including impairment of tissue integrity and production of inflammatory mediators and angiogenic factors. This can lead to immune suppression and enhanced growth or adhesion of tumor cells, all of which increase the chance of exfoliated tumor cells developing into secondary malignancies.

CONCLUSIONS

Because surgery remains the appropriate and necessary means of treatment for most CRC patients, new adjuvant therapeutic strategies that prevent tumor recurrence after surgery need to be explored since the perioperative therapeutic window of opportunity offers promising means of improving patient outcome but is unfortunately underutilized.

Minimally invasive colon resection is associated with a transient increase in plasma sVEGFR1 levels and a decrease in sVEGFR2 levels during the early postoperative period

INTRODUCTION

Plasma vascular endothelial growth factor (VEGF) levels are elevated for 2-4 weeks after minimally invasive colorectal resection (MICR). VEGF induces wound and tumor angiogenesis by binding to endothelial cell (EC)-bound VEGF-receptor 1 (VEGFR1) and VEGFR2. Soluble receptors (sVEGFR1, sVEGFR2) sequester VEGF in the blood and decrease VEGF's proangiogenic effect. The importance of the MICR-related VEGF changes depends on the effect of surgical procedures on sVEGFR1 and sVEGFR2; this study assessed levels of these proteins after MICR for benign indications.

METHODS

Blood samples were taken (n=39) preoperatively (preop) and on postoperative days (POD) 1 and 3; in most cases a fourth sample was drawn between POD 7 and 30. sVEGFR1 and sVEGFR2 levels were measured via enzyme-linked immunosorbent assay (ELISA), which detects free and VEGF bound soluble receptor. Late samples were bundled into POD 7-13 and POD 14-30 time points. Results are reported as mean and standard deviation. The data was assessed with paired-samples t-test.

RESULTS

Preop, mean plasma sVEGFR2 level (9,203.7+/-1,934.3 pg/ml) was significantly higher than the sVEGFR1 value (132.5+/-126.2 pg/ml). sVEGFR2 levels were significantly lower on POD 1 (6,957.8+/-1,947.7 pg/ml,) and POD 3 (7,085.6+/-2,000.2 pg/ml), whereas sVEGFR1 levels were significantly higher on POD 1 (220.0+/-132.8 pg/ml) and POD 3 (182.7+/-102.1 pg/ml) versus preop results. No differences were found on POD 7-13 or 14-30.

CONCLUSIONS

sVEGFR2 values decreased and sVEGFR1 levels increased early after MICR; due to its much higher baseline, the sVEGFR2 changes dominate. The net result is less VEGF bound to soluble receptor and more free plasma VEGF.

Colorectal resection, both open and laparoscopic-assisted, in patients with benign indications is associated with proangiogenic changes in plasma angiopoietin 1 and 2 levels

INTRODUCTION

Plasma vascular endothelial growth factor (VEGF) levels are increased after surgery and may stimulate tumor growth after cancer resection. Angiopoietin 1 (Ang 1) and Ang 2 are proteins that impact VEGF-related angiogenesis (VRA). Ang 1 stabilizes mature vessels and inhibits VRA, whereas Ang 2 destabilizes vessels and promotes VRA. The ratio of Ang 1 to Ang 2 reflects the net effect; a low ratio promotes VRA. This study's purpose was to determine the impact of open and minimally invasive (MIS) colorectal resection (CR) for benign indications on plasma Ang 1 and 2 levels.

METHODS

A total of 30 patients operated by MIS and 26 operated by open procedure were studied. Plasma was obtained preoperatively (PO) and on postoperative days (POD) 1 and 3. Plasma Ang 1 and Ang 2 levels were assessed via enzyme-linked immunosorbent assay (ELISA) in duplicate. Data were compared using Wilcoxon's matched-pair test and the Mann-Whitney U-test (significance p < 0.05).

RESULTS

Indications, types of resection, and morbidity for the groups were similar. The mean MIS incision length was 4.7 +/- 1.6 cm while it was 16.8 +/- 7.1 cm for the open group (p = 0.0001). For both groups Ang 2 levels were significantly higher and the Ang 1 to Ang 2 ratio was significantly lower on POD 1 and 3 compared with preoperative results. Ang 1 levels were significantly decreased on POD 1 and 3 in the MIS group but only on POD 1 in the open group. For unclear reasons, preoperative Ang 1 levels and Ang 1 to Ang 2 ratios were significantly different between the groups, which precludes comparison of the postoperative results between groups.

CONCLUSION

CR for benign pathology results in higher Ang 2 levels, lower Ang 1 levels, and lower Ang 1 to Ang 2 ratios early after surgery. These alterations are proangiogenic. These results, plus the already noted VEGF increases, suggest that surgery results in proangiogenic plasma protein changes that may stimulate tumor growth early after surgery. The duration of the Ang 1 and 2 changes needs to be determined.