Mechanisms of lymphatic metastasis in human colorectal adenocarcinoma

The role of sphingosine-1-phosphate in breast cancer tumor-induced lymphangiogenesis

Sphingosine-1-phosphate (S1P) is a potent sphingolipid metabolite that regulates a number of biological processes critical for cancer. S1P produced inside cancer cells is exported and exerts its extracellular functions by binding to its specific receptors in an autocrine, paracrine, and/or endocrine manner, which is known as inside-out signaling. S1P is also known to exert its intracellular functions especially in the inflammatory process, but its relevance to cancer biology remains to be elucidated. Recently, there have been growing interests in the role of S1P in breast cancer progression, including angiogenesis and lymphangiogenesis. Our group demonstrated that activation of sphingosine kinase 1, the enzyme that catalyzes the phosphorylation of sphingosine to S1P, is a key step of this process. In this review, we will cover our current knowledge on the role of S1P signaling pathway in breast cancer progression with an emphasis on its role in tumor-induced lymphangiogenesis.

Correlation between mitochondrial TRAP-1 expression and lymph node metastasis in colorectal cancer

AIM: To evaluate the effect of mitochondrial tumor necrosis factor receptor-associated protein-1 (TRAP-1) on the lymph node metastasis (LNM) in Chinese colorectal cancer (CRC) patients, and develop potential LNM-associated biomarkers for CRC using quantitative real-time polymerase chain reaction (RT-PCR) analysis.

METHODS: Differences in mitochondrial TRAP-1 gene expression between primary CRC with LNM (LNM CRC) and without LNM (non-LNM CRC) were assessed in 96 Chinese colorectal carcinoma samples using quantitative RT-PCR analysis, Western blotting, and confirmed with immunohistochemical assay. The relationship between clinicopathological parameters and potential diagnostic biomarkers was also examined.

RESULTS: TRAP-1 was significantly upregulated in LNM CRC compared with non-LNM CRC, which was confirmed by RT-PCR, Western blotting and immunohistochemical assay. The expression of TRAP-1 in two different metastatic potential human colorectal cancer cell lines, LoVo and HT29, was analyzed with Western blotting. The expression level of TRAP-1 was dramatically higher in LoVo than in HT29. Overexpression of TRAP-1 was significantly associated with LNM (90.2% in LNM group vs 22% in non-LNM group, P < 0.001), the advanced tumor node metastasis stage (89.1% in LNM group vs 26.9% in non-LNM group, P < 0.001), the increased 5-year recurrence rate (82.7% in LNM group vs 22.6% in non-LNM group, P < 0.001) and the decreased 5-year overall survival rate (48.4% in LNM vs 83.2% in non-LNM group, P < 0.001). Univariate and multivariate analyses indicated that TRAP-1 expression was an independent prognostic factor for recurrence and survival of CRC patients (Hazard ratio of 2.445 in recurrence, P = 0.017; 2.867 in survival, P = 0.028).

CONCLUSION: Mitochondria TRAP-1 affects the lymph node metastasis in CRC, and may be a potential biomarker for LNM and a prognostic factor in CRC. Over-expression of TRAP-1 is a predictive factor for the poor outcome of colorectal cancer patients.

Lymphovascular and perineural invasion as selection criteria for adjuvant therapy in intrahepatic cholangiocarcinoma: a multi-institution analysis

OBJECTIVES

Criteria for the selection of patients for adjuvant chemotherapy in intrahepatic cholangiocarcinoma (IHCC) are lacking. Some authors advocate treating patients with lymph node (LN) involvement; however, nodal assessment is often inadequate or not performed. This study aimed to identify surrogate criteria based on characteristics of the primary tumour.

METHODS

A total of 58 patients who underwent resection for IHCC between January 2000 and January 2010 at any of three institutions were identified. Primary outcome was overall survival (OS).

RESULTS

Median OS was 23.0 months. Median tumour size was 6.5 cm and the median number of lesions was one. Overall, 16% of patients had positive margins, 38% had perineural invasion (PNI), 40% had lymphovascular invasion (LVI) and 22% had LN involvement. A median of two LNs were removed and a median of zero were positive. Lymph nodes were not sampled in 34% of patients. Lymphovascular and perineural invasion were associated with reduced OS [9.6 months vs. 32.7 months (P= 0.020) and 10.7 months vs. 32.7 months (P= 0.008), respectively]. Lymph node involvement indicated a trend towards reduced OS (10.7 months vs. 30.0 months; P= 0.063). The presence of either LVI or PNI in node-negative patients was associated with a reduction in OS similar to that in node-positive patients (12.1 months vs. 10.7 months; P= 0.541). After accounting for adverse tumour factors, only LVI and PNI remained associated with decreased OS on multivariate analysis (hazard ratio 4.07, 95% confidence interval 1.60-10.40; P= 0.003).

CONCLUSIONS

Lymphovascular and perineural invasion are separately associated with a reduction in OS similar to that in patients with LN-positive disease. As nodal dissection is often not performed and the number of nodes retrieved is frequently inadequate, these tumour-specific factors should be considered as criteria for selection for adjuvant chemotherapy.

Inducing apoptosis in rolling cancer cells: a combined therapy with aspirin and immobilized TRAIL and E-selectin

Though metastasis is considered an inefficient process, over 90% of cancer related deaths are attributed to the formation of secondary tumors. Thus, eliminating circulating cancer cells could lead to improved patient survival. This study was aimed at exploiting the interactions of cancer cells with selectins under flow to selectively kill captured colon cancer cells. Microtubes functionalized with E-selectin and TRAIL were perfused with colon cancer cell line Colo205 either treated with 1 mM aspirin or untreated for 1 or 2 h. Cells were collected from the microtube and analyzed by flow cytometry. Aspirin treatment alone killed only 3% cells in culture. A 95% difference in the number of cells killed between control and TRAIL + ES surfaces was seen when aspirin treated cells were perfused over the functionalized surface for 2 h. We have demonstrated a novel biomimetic method to capture and neutralize cancer cells in flow, thus reducing the chances for the formation of secondary tumors.

Clinical significance of lymph vessel density in T3 colorectal carcinoma

PURPOSE

The purpose of the present study is to characterise the lymphatic vessel density (LVD) in the T3 colorectal carcinoma and to correlate it with N status, grading and presence of tumour budding.

METHODS

A total of 56 cases of T3 colorectal carcinoma were retrieved from the pathology's archive of Klinikum Augsburg. All slides were stained immunohistochemically with D2-40 (lymphatic endothelium) and with pancytokeratin to assess the tumour budding. Tumour budding and lymph vessel density were investigated independently by BM and CC. The highest density of lymphatic vessels was counted both in tumour centre (ILVD) and at the periphery of the tumour (PLVD) within an area of 0.24 mm(2).

RESULTS

Due to the strong intra-observer (BM and CC) difference in ILVD and PLVD, all cases were re-evaluated establishing a consensus that has been used for the further analyses. There was a significant difference between PLVD and ILVD (12 ± 4 versus 6 ± 3; P < 0.001). Moreover, we found a non-significant trend towards high PLVD in the cases with nodal metastasis versus the negative one, 13 ± 5/hpf versus 11 ± 4 (P = 0.072). There was no association between tumour budding and ILVD and PLVD (P = 0.249 and 0.38).

CONCLUSION

Colorectal carcinoma induces lymphangiogenesis. A higher PLVD could increase the capability of cancer cell to invade the lymphatic system. However, the obvious difficulties in immunohistochemical evaluation and the rather small differences between nodal positive and negative cases in T3 colorectal cancer seem to limit the clinical value of LVD evaluation.

The extra domain A of fibronectin increases VEGF-C expression in colorectal carcinoma involving the PI3K/AKT signaling pathway

The extra domain A (EDA)-containing fibronectin (EDA-FN), an alternatively spliced form of the extracellular matrix protein fibronectin, is predominantly expressed in various malignancies but not in normal tissues. In the present study, we investigated the potential pro-lymphangiogenesis effects of extra domain A (EDA)-mediated vascular endothelial growth factor-C (VEGF-C) secretion in colorectal carcinoma (CRC). We detected the expressions of EDA and VEGF-C in 52 human colorectal tumor tissues and their surrounding mucosae by immunohistochemical analysis, and further tested the correlation between the expressions of these two proteins in aforementioned CRC tissues. Both EDA and VEGF-C were abundantly expressed in the specimens of human CRC tissues. And VEGF-C was associated with increased expression of EDA in human CRC according to linear regression analysis. Besides, EDA expression was significantly correlated with lymph node metastasis, tumor differentiation and clinical stage by clinicopathological analysis of tissue microarrays containing tumor tissues of 115 CRC patients. Then, human CRC cell SW480 was transfected with lentivectors to elicit expression of shRNA against EDA (shRNA-EDA), and SW620 was transfected with a lentiviral vector to overexpress EDA (pGC-FU-EDA), respectively. We confirmed that VEGF-C was upregulated in EDA-overexpressed cells, and downregulated in shRNA-EDA cells. Moreover, a PI3K-dependent signaling pathway was found to be involved in EDA-mediated VEGF-C secretion. The in vivo result demonstrated that EDA could promote tumor growth and tumor-induced lymphangiogenesis in mouse xenograft models. Our findings provide evidence that EDA could play a role in tumor-induced lymphangiogenesis via upregulating autocrine secretion of VEGF-C in colorectal cancer, which is associated with the PI3K/Akt-dependent pathway.

Recombinant human endostatin endostar inhibits tumor growth and metastasis in a mouse xenograft model of colon cancer

To investigate the effects of recombinant human endostatin Endostar on metastasis and angiogenesis and lymphangiogenesis of colorectal cancer cells in a mouse xenograft model. Colon cancer cells SW620 were injected subcutaneously into the left hind flank of nude mice to establish mouse xenograft models. The mice were treated with normal saline or Endostar subcutaneously every other day. The growth and lymph node metastasis of tumor cells, angiogenesis and lymphangiogenesis in tumor tissue were detected. Apoptosis and cell cycle distribution were studied by flow cytometry. The expression of VEGF-A, -C, or -D in SW620 cells was determined by immunoblotting assays. Endostar inhibited tumor growth and the rate of lymph node metastasis (P < 0.01). The density of blood vessels in or around the tumor area was 12.27 ± 1.21 and 22.25 ± 2.69 per field in Endostar-treated mice and controls (P < 0.05), respectively. Endostar also decreased the density of lymphatic vessels in tumor tissues (7.84 ± 0.81 vs. 13.83 ± 1.08, P < 0.05). Endostar suppresses angiogenesis and lymphangiogenesis in the lymph nodes with metastases, simultaneously. The expression of VEGF-A, -C and -D in SW620 cells treated with Endostar was substantially lower than that of controls. Endostar inhibited growth and lymph node metastasis of colon cancer cells by inhibiting angiogenesis and lymphangiogenesis in a mouse xenograft model of colon cancer.

Macrophages are important mediators of either tumor- or inflammation-induced lymphangiogenesis

The lymphatic system provides important functions for tissue fluid homeostasis and immune response. Lymphangiogenesis, the formation of new lymphatics, comprises a series of complex cellular events in vitro or in vivo, e.g., proliferation, differentiation, and sprouting. Recent evidence has implied that macrophages act as a direct structural contributor to lymphatic endothelial walls or secret VEGF-C/-D and VEGF-A to initiate lymphangiogenesis in inflamed or tumor tissues. Bone marrow-derived macrophages are versatile cells that express different functional programs in response to exposure to microenvironmental signals, and can be identified by specific expression of a number of proteins, F4/80, CD11b, and CD68. Several causative factors, e.g., NF-κB, IL-1β, TNF-α, SDF-1, M-CSF, especially TonEBP/VEGF-C signaling, may be actively involved in macrophage-induced lymphangiogenesis. Alteration of macrophage phenotype and function has a profound effect on the development and progression of inflammation and malignancy, and macrophage depletion for controlling lymphangiogenesis may provide a novel approach for prevention and treatment of lymphatic-associated diseases.

Downregulation of S100A4 expression by RNA interference suppresses cell growth and invasion in human colorectal cancer cells

S100A4 protein, a member of the S100 superfamily of calcium-binding proteins, is frequently observed in various types of human cancers, including colorectal cancer (CRC). Our previous investigations have demonstrated that the overexpression of S100A4 is associated with lymph node metastasis and poor prognosis in CRC; however, its biological roles in CRC remain unclear. In the present study, we compared the expression of S100A4 at the mRNA and protein levels in six CRC cell lines, and found that the expression levels roughly coincided with their invasiveness. Using RNA interference, we suppressed S100A4 expression in SW620 CRC cells with highly invasive potential and S100A4 high expression. The specific knockdown of S100A4 strongly suppressed cell growth, migration and invasion activities. Furthermore, employing metastasis-related gene mRNA microarrays, we found four genes to be significantly dysregulated (more than 2-fold) after downregulation of S100A4, including three downregulated genes (MMP9, MMP10 and CDH11) and one upregulated gene (TIMP4). Our present results indicate that S100A4 may positively regulate tumor cell proliferation, invasion and metastasis associated with multiple molecules. Thus, the inhibition of S100A4 might be a potentially novel approach to treatment for CRC.

Lymphatic microvessel density as a prognostic factor in non-small cell lung carcinoma: a meta-analysis of the literature

The role of lymphatic microvessel density (LVD) as a prognostic factor for survival of patients with non-small cell lung carcinoma (NSCLC) remains controversial. To evaluate this potential role, we performed a systematic review of the electronic databases PubMed and EMBASE for relevant literature to review and compile available survival results. To be eligible, a study had to assess LVD in patients with NSCLC and to compare survival based on LVD stratification. Among 12 eligible trials, all dealt with NSCLC, and 10 trials provided results for the meta-analysis of survival data (evaluable trials). In terms of survival, high LVD was reported to be an unfavorable prognostic factor for overall survival in 8 studies, whereas it was not in 4 studies. The overall survival hazard ratio for the 10 evaluable studies (1,426 patients) was calculated to be 1.41 (95% CI: 1.14-1.75) using a random effects model, indicating a poorer survival for NSCLC patients with high LVD. The hazard ratio was 1.52 (95% CI: 1.10-2.11) in 5 NSCLC studies where LVD was assessed based on D2-40 and 1.31 (95% CI: 1.08-1.60) in 4 studies where LVD was measured based on vascular endothelial growth factor receptor-3. This study supports the hypothesis that the lymphatic microvessel count or LVD, which reflects levels of lymphangiogenesis, is a poor prognostic factor for patient survival in surgically treated NSCLC. However, the present findings may overestimate the prognostic capacity of LVD because of publication and report bias. In addition, the standardization of lymphangiogenesis assessment by the lymphatic microvessel count is necessary.

Lymphangiogenesis in regional lymph nodes is an independent prognostic marker in rectal cancer patients after neoadjuvant treatment

One of the major prognostic factors in rectal cancer is lymph node metastasis. The formation of lymph node metastases is dependent on the existence of a premetastatic niche. An important factor preceding metastasis are lymph vessels which are located in the lymph node. Accordingly, the occurrence of intranodal lymphangiogenesis is thought to indicate distant metastasis and worse prognosis. To evaluate the significance of lymph node lymphangiogenesis, we studied formalin fixed, paraffin embedded adenocarcinomas and regional lymph nodes of 203 rectal cancer patients who were treated with neoadjuvant radiochemotherapy and consecutive curative surgery with cancer free surgical margins (R0). Regional lymph node lymph vessels were detected by immunohistochemistry for podoplanin (D2-40). Our results show that the presence of lymphatic vessels in regional lymph nodes significantly affects the disease-free survival in univariate and multivariate analyses. In contrast, there was no correlation between peritumoral or intratumoral lymph vessel density and prognosis. Indeed, our study demonstrates the importance of lymphangiogenesis in regional lymph nodes after neoadjuvant radiochemotherapy and consecutive surgery as an independent prognostic marker. Staining for intranodal lymphangiogenesis and methods of intravital imaging of lymphangiogenesis and lymphatic flow may be a useful strategy to predict long-term outcome in rectal cancer patients. Furthermore, addition of VEGF-blocking agents to standardized neoadjuvant treatment schemes might be indicated in advanced rectal cancer.

Roles of VEGF-C and Smad4 in the lymphangiogenesis, lymphatic metastasis, and prognosis in colon cancer

BACKGROUND/AIMS

We combined two different signal pathways on transforming growth factor β1 (TGF-β1)-Smad and vascular endothelial growth factor C (VEGF-C)/VEGF receptors for exploring changes in pathway members and their influence on lymphangiogenesis and clinicopathological features.

MATERIALS AND METHODS

Expression of TGF-β1, TGF-βRII, Smad4, VEGF-C, and VEGFR-3 was immunohistochemically evaluated in 147 colon cancer patients who were followed up for 5 years.

RESULTS

Lymphatic vessel density in colon cancer tissues was significantly higher than in normal colonic tissues. Smad4 expression negatively correlated with lymphatic vessel count and VEGF-C expression. VEGF-C expression positively correlated with lymphatic vessel count. Analysis using the Kaplan-Meier method indicated that patients with VEGF-C-positive tumors had significantly shorter overall survival and tumor-free survival time than those with VEGF-C-negative tumors. Patients with Smad4-negative tumors had significantly shorter overall survival and tumor-free survival time than those with Smad4-positive tumors.

CONCLUSIONS

Both Smad4 and VEGF-C are involved in lymphangiogenesis and lymphatic metastasis. Smad4 and VEGF-C expression may be clinically useful indicators for prognostic evaluation in colon cancer patients.

Lymph vessel density in seminomatous testicular cancer assessed with the specific lymphatic endothelium cell markers D2-40 and LYVE-1: correlation with pathologic parameters and clinical outcome

OBJECTIVES

To evaluate the role of lymph vessel density (LVD) and lymphangiogenesis in seminomatous testicular cancer (STC) by using the lymphatic endothelial cell (LEC) markers LYVE-1 and D2-40.

METHODS AND MATERIALS

Paraffin embedded tumor specimens from 40 patients with STC were stained by specific D2-40 and Lyve-1 antibodies. LVD was measured in different representative and standardized areas. Fluorescence double immunostaining for Lyve-1 and Ki-67 was performed and results were correlated with clinicopathologic data. The median follow-up period was 55 (range 10-135) months.

RESULTS

Mean intratumoral LVD (D2-40: 1.30 ± 1.99; Lyve-1: 1.82 ± 2.34) was significantly lower than peritumoral LVD (D2-40: 4.94 ± 2.58; Lyve-1: 4.62 ± 2.73) and LVD in nontumoral areas (D2-40: 4.81 ± 3.79; Lyve-1: 4.22 ± 3.19). There was no significant difference between LVD measures when using D2-40 or LYVE-1. Detection rates of lymphatic vascular invasion (LVI) were significantly higher than in conventional HE-stained sections (77.5% vs. 52.5%). No proliferating lymphatic vessels were found.

CONCLUSIONS

We found that LVD is decreased within tumor areas of STC. Despite a higher peritumoral LVD, no signs of proliferating endothelial cells were observed, suggesting a lack of lymphangiogenesis in STC. Detection of LVI can be optimized by specific D2-40 or LYVE-1 staining.

Systematic review of prognostic factors related to overall survival in patients with stage IV colorectal cancer and unresectable metastases

BACKGROUND

With the improvements in newer chemotherapeutic agents, the role of primary tumour resection in patients with stage IV colorectal cancer is controversial. In many cases primary tumour resection is still favoured as first-line management. However, a detailed understanding of independent prognostic factors related to survival is necessary before making this decision.

METHOD

A literature search was conducted using Medline and Embase. Studies that performed multivariate analysis on overall survival of patients with incurable stage IV colorectal cancer were included in this review.

RESULTS

Fourteen retrospective studies involving 3209 patients were included. Clinical variables analysed to consistently have independent prognostic significance for long-term survival included the patients' performance status (<2), volume of liver metastases (<50%), nodal stage (N0), disease-free resection margins, and treatment with chemotherapy and/or primary tumour resection. Cancer antigen (CA) 19-9, low albumin, elevated ALP levels, apical lymph node involvement, presence of ascites, and postoperative transfusion were each assessed by only one study and found to be independently associated with survival. Factors inconsistently reported to have independent prognostic significance were age, ASA score, preoperative CEA levels, primary tumour location, tumour size and differentiation, peritoneal dissemination, and extrahepatic metastases.

CONCLUSION

Each patient should be reviewed individually on the basis of the above independent prognostic factors before deciding to resect the primary tumour. Patients with a poor performance status, extensive hepatic metastases, and extensive nodal disease detected preoperatively are less likely to have a survival benefit. Nonsurgical approaches to manage these patients should be given careful consideration.

Process of distant lymph node metastasis in colorectal carcinoma: implication of extracapsular invasion of lymph node metastasis

BACKGROUND

We previously demonstrated that extracapsular invasion (ECI) at a metastatic sentinel node was significantly associated with the presence of positive non-sentinel nodes in patients with breast cancer. However, the mechanism of metastatic spreading of tumor cells to distant lymph nodes in patients with colorectal carcinoma is not fully understood. In this study, we investigated the factors that may determine the likelihood of additional regional lymph node metastasis when metastasis is found in nodes at the N1 site in colorectal cancer, especially focusing on the presence of ECI.

METHODS

Two hundred and twenty-eight consecutive patients who underwent colorectal resection were identified for inclusion in this study, of which 37 (16.2%) had positive lymph nodes at the N1 site. Six of these 37 cases had additional metastasis in N2 site lymph nodes. We reviewed the clinicopathological features of these cases and performed statistical analysis of the data.

RESULTS

In the univariate analysis ECI at the N1 site was the only factor significantly associated with the presence of cancer cells in the N2 site. Other factors, including number of positive lymph nodes, lymphovascular invasion of the primary tumor, tumor size and tumor depth of invasion, were not associated with metastatic involvement at the N2 site.

CONCLUSIONS

Our results suggest that the presence of ECI at metastatic lymph nodes at the N1 site is correlated with further metastasis at the N2 site. These findings imply the possibility that ECI might indicate the ability of colorectal tumor cells to disseminate to distant lymph nodes.

Impact of CD39 and purinergic signalling on the growth and metastasis of colorectal cancer

Despite improvements in prevention and management of colorectal cancer (CRC), uncontrolled tumor growth with metastatic spread to distant organs remains an important clinical concern. Genetic deletion of CD39, the dominant vascular and immune cell ectonucleotidase, has been shown to delay tumor growth and blunt angiogenesis in mouse models of melanoma, lung and colonic malignancy. Here, we tested the influence of CD39 on CRC tumor progression and metastasis by investigating orthotopic transplanted and metastatic cancer models in wild-type BALB/c, human CD39 transgenic and CD39 deficient mice. We also investigated CD39 and P2 receptor expression patterns in human CRC biopsies. Murine CD39 was expressed by endothelium, stromal and mononuclear cells infiltrating the experimental MC-26 tumors. In the primary CRC model, volumes of tumors in the subserosa of the colon and/or rectum did not differ amongst the treatment groups at day 10, albeit these tumors rarely metastasized to the liver. In the dissemination model, MC-26 cell line-derived hepatic metastases grew significantly faster in CD39 over-expressing transgenics, when compared to CD39 deficient mice. Murine P2Y2 was significantly elevated at both mRNA and protein levels, within the larger liver metastases obtained from CD39 transgenic mice where changes in P2X7 levels were also noted. In clinical samples, lower levels of CD39 mRNA in malignant CRC tissues appeared associated with longer duration of survival and could be linked to less invasive tumors. The modulatory effects of CD39 on tumor dissemination and differential levels of CD39, P2Y2 and P2X7 expression in tumors suggest involvement of purinergic signalling in these processes. Our studies also suggest potential roles for purinergic-based therapies in clinical CRC.

Loss of E-cadherin independently predicts the lymph node status in colorectal cancer

BACKGROUND

The identification of biomarkers that improve risk stratification in patients with colorectal cancer (CRC) is still a challenge. The objective of our study was to identify independent protein markers as predictors of lymph node (N) stage in CRC.

METHODS

Tumour specimens from 221 CRC patients were mounted onto a multiple-punch tissue microarray and evaluated for 21 tumour related factors and one host related factor involved in CRC carcinogenesis, namely β-catenin, E-cadherin, EGFR, pERK, RHAMM, pAKT, pSMAD2, p21, p16, Bcl-2, Ki-67, APAF-1, MST1, RKIP, VEGF, EphB2, MMP7, Laminin5γ2, MUC1, CDX2, caspase-3 as well as intra-tumoural and stromal CD8+ tumour infiltrating lymphocytes (iTILs and sTILs).

RESULTS

Node positive cancers showed significant losses for p21 (p = 0.026), Bcl-2 (p = 0.027), APAF-1 (p = 0.033), EphB2 (p = 0.006), E-cadherin (p < 0.001), RKIP (p = 0.019), CD8+ iTILs and sTILs (p < 0.001 and p = 0.008, respectively) and cytoplasmic MST1 (p = 0.014). Based on the area under the receiver operating characteristic curve (AUC) EphB2, E-cadherin, iTILs and sTILs were identified as potential predictors of N stage (AUC values >0.6), but only loss of E-cadherin was an independent predictor in multivariate analysis.

CONCLUSIONS

E-cadherin appears to be a strong predictor of N stage in CRC and should be considered in pre-operative and post-operative management of colon and rectal cancer patients.

Metastasis-associated protein 1 induces VEGF-C and facilitates lymphangiogenesis in colorectal cancer

AIM

To study the correlation between high metastasis-associated protein 1 (MTA1) expression and lymphangiogenesis in colorectal cancer (CRC) and its role in production of vascular endothelial growth factor-C(VEGF-C).

METHODS

Impact of high MTA1 and VEGF-C expression levels on disease progression and lymphovascular density (LVD, D2-40-immunolabeled) in 81 cases of human CRC was evaluated by immunohistochemistry. VEGF-C mRNA and protein expressions in human LoVo and HCT116 cell lines were detected by real-time polymerase chain reaction and Western blotting, respectively, with a stable expression vector or siRNA.

RESULTS

The elevated MTA1 and VEGF-C expression levels were correlated with lymph node metastasis and Dukes stages (P < 0.05). Additionally, high MTA1 expression level was correlated with a large tumor size (P < 0.05). A significant correlation was found between MTA1 and VEGF-C protein expressions in tumor cells (r = 0.371, P < 0.05). Similar to the VEGF-C expression level, high MTA1 expression level was correlated with high LVD in CRC (P < 0.05). Furthermore, over-expression of MTA1 significantly enhanced the VEGF-C mRNA and protein expression levels, whereas siRNAs - knocked down MTA1 decreased the VEGF-C expression level.

CONCLUSION

MTA1, as a regulator of tumor-associated lymphangiogenesis, promotes lymphangiogenesis in CRC by mediating the VEGF-C expression.

Expression of β-catenin and VEGF-C/-D in colorectal cancer

AIM: To investigate the expression of β-catenin and vascular endothelial growth factor-C/-D (VEGF-C/-D) in colorectal cancer (CRC) and to analyze their significance.

METHODS: The expression of β-catenin and VEGF-C/-D in 96 CRC specimens were detected by immunohistochemistry.

RESULTS: In normal colonic mucosa, β-catenin was detected on the plasma membrane of epithelial cells. Reduced membrane expression of β-catenin was noted in CRC, and 67.71% of cases of CRC showed cytoplasmic and nuclear expression of β-catenin. The positive rates of VEGF-C/-D expression were significantly higher in tumor tissue than in normal mucosa (43.75% vs 19.79%; 38.54% vs 13.54%, both P < 0.01). The expression of β-catenin had a significantly positive correlation with that of VEGF-C/-D (both P < 0.01).

CONCLUSION: Cytoplasmic and nuclear β-catenin expression may induce VEGF-C/-D overexpression in CRC, which may play an important role in lymphangiogenesis in CRC.

[The therapeutic contribution of proteomic approaches in cancers]

Up to now, there are no protein tumor markers with a specificity and sensitivity sufficient to have a utility in prognosis and early diagnosis of cancer. Recent advances in proteomics approaches have led to the identification of novel tumor markers of cancer that may have a utility in screening strategies and treatment. The purpose of the current review is to describe the major advances in cancer proteomics, especially those related to the study of serum biomarkers, immune-related responses (autoantibodies) and alterations in cellular proteins.

S100A4 over-expression underlies lymph node metastasis and poor prognosis in colorectal cancer

AIM: To develop lymph node metastasis (LNM)-associated biomarkers for colorectal cancer (CRC) using quantitative proteome analysis.

METHODS: Differences in protein expression between primary CRC with LNM (LNM CRC) and without LNM (non-LNM CRC) were assessed using methyl esterification stable isotope labeling coupled with 2D liquid chromatography followed by tandem mass spectrometry (2D-LC-MS/MS). The relationship to clinicopathological parameters and prognosis of candidate biomarkers was examined using an independent sample set.

RESULTS: Forty-three proteins were found to be differentially expressed by at least 2.5-fold in two types of CRC. S100A4 was significantly upregulated in LNM CRC compared with non-LNM CRC, which was confirmed by Western blotting, immunohistochemistry and real-time quantitative polymerase chain reaction. Further immunohistochemistry on another 112 CRC cases showed that overexpression of S100A4 frequently existed in LNM CRC compared with non-LNM CRC (P < 0.001). Overexpression of S100A4 was significantly associated with LNM (P < 0.001), advanced TNM stage (P < 0.001), increased 5-year recurrence rate (P < 0.001) and decreased 5-year overall survival rate (P < 0.001). Univariate and multivariate analyses indicated that S100A4 expression was an independent prognostic factor for recurrence and survival of CRC patients (P < 0.05).

CONCLUSION: S100A4 might serve as a powerful biomarker for LNM and a prognostic factor in CRC.

Expression of p16 in lymph node metastases of adjuvantly treated stage III colorectal cancer patients identifies poor prognostic subgroups: a retrospective analysis of biomarkers in matched primary tumor and lymph node metastases

BACKGROUND

The objective of identifying protein biomarkers for patients with stage III and IV colorectal cancer is to improve risk stratification and, thus, to identify patients in the postoperative setting who may benefit from more targeted treatment. The objective of the current study was to determine the prognostic value of 19 protein markers assessed in primary tumors and matched lymph node (LN) metastases from patients with stage III and IV colorectal cancer.

METHODS

Matched primary tumors and LN metastases from 82 patients with stage III and IV colorectal cancer were mounted onto a multiple-punch tissue microarray and were stained for 19 protein markers involved in tumor progression (β-catenin, E-cadherin, epidermal growth factor receptor, phosphorylated extracellular signal-regulated kinase [pERK], receptor for hyaluronic acid-mediated motility, phosphorylated protein kinase B, p21, p16, B-cell lymphoma 2, Ki67, apoptotic protease activating factor 1, mammalian sterile 20-like kinase 1, Raf kinase inhibitor protein, vascular endothelial growth factor, ephrin type-B receptor 2, matrix metalloproteinase 7, laminin5γ2, mucin 1 [MUC1], and caudal-related homeobox 2). The prognostic effects of biomarkers in both primary tumor and positive LNs were assessed.

RESULTS

MUC1, pERK and p16 in LN (P=.002, P=.014, and P=.002, respectively) had independent prognostic value. In patients with stage III disease who received adjuvant treatment, negative p16 expression was associated with highly unfavorable outcomes overall (hazard ratio [HR], 0.26; 95% confidence interval [CI], 0.1-0.6; P=.005) when the analysis was stratified by pathologic tumor classification (HR, 0.25; 95% CI, 0.1-0.7; P=.005), age (HR, 0.23; 95% CI, 0.1-0.6; P=.004), and LN ratio (HR, 0.26; 95% CI, 0.1-0.7; P=.007); and, in multivariate analysis, it was associated with performance status and the receipt of folic acid treatment (HR, 0.29; 95% CI, 0.09-0.89; P=.03).

CONCLUSIONS

The loss of p16 in LN metastases contributed to adverse outcomes in adjuvantly treated patients with stage III colorectal cancer independent of pathologic tumor classification, age, LN ratio, performance status, or folic acid treatment. The current results support the investigation of p16 as a prognostic and potential predictive biomarker for future randomized trials of patients with stage III colorectal cancer.

Endostatin inhibits tumour lymphangiogenesis and lymphatic metastasis via cell surface nucleolin on lymphangiogenic endothelial cells

Endostatin has potent anti-endothelial and anti-angiogenic functions. Endostatin was reported to reduce lymphangiogenesis by down-regulating the level of VEGF-C in tumour tissues. However, there is little evidence for the direct function of endostatin on lymphangiogenic endothelial cells and lymphangiogenic vessels. Here, we report that cell surface nucleolin, which was reported as an endostatin receptor mediating its anti-angiogenic and anti-tumour functions, is also selectively expressed on the cell surface of lymphangiogenic endothelial cells both in vitro and in vivo. Treatment of primary mouse lymphatic endothelial cells (mLECs) by endostatin inhibits mLEC migration, tubule formation, and activation of the Erk pathway in mLECs, while neutralization of cell surface nucleolin or nucleolin knockdown results in loss of the anti-lymphatic endothelial activities of endostatin. Also, anti-nucleolin antibody or lentivirus delivered nucleolin siRNA abolishes the anti-lymphangiogenic function of endostatin in the Matrigel plug assay. Endostatin remarkably inhibits tumour-associated lymphangiogenesis, leading to reduced lymphatic metastasis. Systemic blockade of nucleolin notably abolishes the anti-lymphangiogenic and anti-lymphatic metastatic functions of endostatin. Importantly, endostatin does not affect quiescent lymphatics in normal organs, which is consistent with the lack of expression of cell surface nucleolin in quiescent lymphatics. Taken together, our results demonstrate that endostatin directly acts on lymphangiogenic endothelial cells via cell surface nucleolin, which provides a novel mechanism for the inhibition of tumour lymphangiogenesis and lymphatic metastasis by endostatin.

Subcutaneous Metastatic Adenocarcinoma: An Unusual Presentation of Colon Cancer - Case Report and Literature Review

Subcutaneous metastasis from a visceral malignancy is rare with an incidence of 5.3%. Skin involvement as the presenting sign of a silent internal malignancy is an even rarer event occurring in approximately 0.8%. We report a case of a patient who presented to her dermatologist complaining of rapidly developing subcutaneous nodules which subsequently proved to be metastatic colon cancer, and we provide a review of the literature.

Podoplanin expression in cancerous stroma induces lymphangiogenesis and predicts lymphatic spread and patient survival

CONTEXT

Podoplanin is a mucin-type glycoprotein and a lymphatic endothelial marker. Immunohistochemical staining for podoplanin is currently used as a routine pathologic diagnosis tool in Japan to identify lymphatic invasion of cancer cells. Recent reports suggest that podoplanin and other proangiogenic molecules are expressed in stromal fibroblasts and myofibroblasts.

OBJECTIVE

To analyze the distribution of podoplanin expression in tumor stroma and its clinical and biologic significance.

DESIGN

We performed immunohistochemistry for podoplanin on tissue microarrays from 1350 cases of 14 common cancer types.

RESULTS

Two hundred eighty-seven of 662 cases (43%) showed podoplanin expression in the stromal cells within cancer nests. Stromal podoplanin expression in 14 common cancer types was significantly associated with tumor stage (P < .001), lymph node metastases (P < .001), lymphatic invasion (P  =  .02), and venous invasion (P < .001). The stromal cells positive for podoplanin were also positive for α-smooth muscle actin but negative for desmin, confirming a myofibroblasts phenotype. In contrast, myofibroblasts in inflammatory fibrotic lung diseases were podoplanin negative. Lymphatic vessel density was greater in the stromas with podoplanin expression than in the stroma lacking podoplanin-expressing stromal cells (P  =  .01). Survival data were available for non-small cell lung cancer. Stromal podoplanin expression was associated with poorer prognosis in adenocarcinoma (P < .001) and remains statistically significant after adjustment for sex, age, and stage (P  =  .01).

CONCLUSION

Our data indicate that podoplanin expression in stromal myofibroblasts may function as a proangiogenic biomarker and may serve as a predictive marker of lymphatic/vascular spread of cancer cells and a prognostic marker of patient survival.

Current and emerging concepts in tumour metastasis

Disseminated cancer accounts for most deaths due to malignancy. Despite this, research has focused predominantly on tumour development and progression at the primary site. Recently, attention has shifted towards the field of tumour metastasis. Several new and exciting concepts that have emerged in the past few years may shed light on this complex area. The established canonical theory of tumour metastasis, as a process emerging from a stepwise accumulation of genetic events fuelled by clonal evolution, has been challenged. New evidence suggests that malignant cells can disseminate at a much earlier stage than previously recognized in tumourigenesis. These findings have direct relevance to clinical practice and shed new light on tumour biology. Gene-profiling studies support this theory, suggesting that metastatic ability may be an innate property shared by the bulk of cells present early in a developing tumour mass. There is a growing recognition of the importance of host factors outside the primary site in the development of metastatic disease. The role of the 'pre-metastatic niche' is being defined and with this comes a new understanding of the function of bone marrow-derived progenitor cells in directing the dissemination of malignant cells to distant sites. Current research has highlighted the crucial roles played by non-neoplastic host cells within the tumour microenvironment in regulating metastasis. These new concepts have wide-ranging implications for our overall understanding of tumour metastasis and for the development of cancer therapeutics.

Lymphangiogenesis: A new player in cancer progression

Lymph node metastasis is the hallmark of colon cancer progression, and is considered one of the most important prognostic factors. Recently, there has been growing evidence that tumor lymphangiogenesis (formation of new lymphatic vessels) plays an important role in this process. Here, we review the latest findings of the role of lymphangiogenesis in colorectal cancer progression, and discuss its clinical application as a biomarker and target for new therapy. Understanding the molecular pathways that regulate lymphangiogenesis is mandatory to pave the way for the development of new therapies for cancer. In the future, tailored treatments consisting of combinations of chemotherapy, other targeted therapies, and anti-lymphangiogenesis agents will hopefully improve patient outcomes. This progression to the clinic must be guided by new avenues of research, such as the identification of biomarkers that predict response to treatment.

Characterization of a novel lymph node metastasis model from human colonic cancer and its preclinical use for comparison of anti-metastatic efficacy between oral S-1 and UFT/ LV

Although lymph node metastasis (LNM) is the most critical prognostic factor in colorectal cancer patients, the anti-LNM efficacy of chemotherapeutic agents is largely unknown because of the limitations of reproducible human colorectal cancer LNM models. Here, we developed a new LNM model from a recently established colorectal cancer cell line (COLM-5) and compared the anti-LNM efficacy of two oral formulations of 5-fluorouracil (5-FU) derivatives, S-1 and UFT/leucovorin (LV). COLM-5 cells is a poorly differentiated adenocarcinoma cell line with unique features such as left-sided, beta-catenin cytoplasmic localization, and microsatellite stable phenotype. COLM-5 cells expressed vascular endothelial growth factor (VEGF-C) and exhibited peritumoral lymphangiogenesis. Consequently, they showed high LNM potential at an incidence of approximately 90% when subcutaneously injected into nude mice, allowing use for preclinical study. When chemotherapy with S-1 or UFT/LV started from the micrometastasis stage, not the advanced macroscopic metastasis stage, anti-LNM efficacy of S-1 was significantly higher than that of UFT/LV at the dosage in which antitumor activity of the two drugs against primary subcutaneous tumor was comparable. COLM-5 cells showed expression pattern of 5-FU metabolizing enzymes such as high dihydropyrimidine dehydrogenase (DPD) and low thymidylate synthase (TS)/orotate phosphoribosyltransferase (OPRT) both in vitro and in vivo. These results suggest that the preferential anti-LNM activity of S-1 compared with UFT/LV against high-DPD COLM-5 tumors is due to the higher DPD inhibitory activity of 5-chloro-2, 4-dihydroxypyrimidine (CDHP) present in S-1 than uracil in UFT. The COLM-5 model would be an excellent tool for understanding the basic mechanism of LNM and for preclinical study on the anti-LNM efficacy of the drugs.

Heterogeneity and plasticity of lymphatic endothelial cells

Endothelial cells are found in most organs and tissues in our body. Despite their apparent morphological and functional similarities, endothelial cells exhibit remarkable heterogeneity and plasticity. In a strict sense, no two endothelial cells are identical in terms of their biological, immunological, functional, metabolic, morphological, and anatomical aspects. Their heterogeneity and plasticity are now known to be dependent upon and conferred by their microenvironments, arteriovenous-lymphatic cell identity, organ-specific vascular beds, fluid dynamics, vessel sizes, anatomical locations, physiological and pathological states, and more. Although abundant evidence is available to demonstrate endothelial heterogeneity in the blood vascular system, studies of heterogeneity and plasticity of lymphatic endothelial cells are limited because of the short history of lymphatic research. Nonetheless, a growing body of exciting work has begun to discover that lymphatic endothelial cells are as heterogeneous as blood vascular endothelial cells. In this article, we discuss the heterogeneity and plasticity of lymphatic endothelial cells.

Relapsed colon cancer patient presenting with hematuria 13 years after primary tumor resection: a case report

We report a rare case of postoperative colon cancer recurrence who presented with hematuria 13 years after resection of the primary colonic cancer. The patient was 72 years of age and underwent surgical resection of sigmoid colon cancer at another regional hospital in 1994. Since June 2007, this patient has complained of hematuria and bloody stool. On physical examination, tenderness and a hard, indurated mass was palpable in the lower mid-abdomen. Abdominal computed tomography showed a metastatic tumor at the lower midline peritoneum with invasion of the adjacent abdominal wall. Her serum carcinoembryonic antigen level was elevated to 32 ng/dL. Histopathology revealed metastatic colonic adenocarcinoma in the jejunum and abdominal wall.

Gastrointestinal cancer metastasis and lymphatic advancement

The role of angiogenesis in the growth of solid tumors is well established, but the role of lymphatic vessels and the relationship between lymphangiogenesis and tumor spread are less clear. Recently, the molecular pathway that signals lymphangiogenesis and specific markers for lymphatic endothelium have been discovered; however, the lymphatic pathway of cancer metastasis is only partly clarified. Several investigators from the mid 20th century indicated the existence of lymphatico-venous communications, and some observed the retrograde filling of lymph flow and lymphatico-venous communication in obstructive lymphopathy. In the 1960s Burn reported the importance of lymphovenous communication in his clinical and animal experimental data. Thus, the role of potential peripheral lymphatico-venous communication must be considered in the mechanism of cancer metastasis. We observed the lymphatico-venous (portal) communication, as well as lymph retention and reflux, in a rat model of mesenteric lymph vessel obstruction. Based on the phenomenon of lymphatico-venous communication and lymph flow reflux by lymphatic obstruction, we speculate that tumor cell obstruction in the lymph system will lead to the establishment of liver and/or peritoneal metastasis. Clinically, we observed extranodal cancer invasion in a model of lymphatic obstruction, and noted a strong relationship between extranodal invasion and liver or peritoneal metastasis. Thus, the existence of peritoneal and liver metastasis via a lymphatic pathway should be considered.

Intratumoral as well as peritumoral lymphatic vessel invasion correlates with lymph node metastasis and unfavourable outcome in colorectal cancer

The aim of this study was to assess the intratumoral and peritumoral distribution of lymphatic vessel density (LVD) and lymphatic vessel invasion (LVI) in colorectal cancer and their relationships with patients' clinicopathological characteristics and survival. Paraffin sections of 81 primary colorectal cancers were examined by immunohistochemical staining using monoclonal antibody D2-40. Peritumoral LVD was significantly higher than intratumoral LVD (P = 0.000). Both intratumoral LVD and peritumoral LVD were correlated with the presence of LVI (P = 0.006 and P = 0.003, respectively). LVI, intratumoral LVI and peritumoral LVI were identified, respectively in 38, 28 and 32% of the samples investigated. Both intratumoral LVI and peritumoral LVI were correlated with lymph node metastasis (P = 0.030 and P = 0.014, respectively). Lymph node metastasis, the presence of intratumoral LVI and peritumoral LVI were adversely associated with the 5-year overall survival in a univariate analysis (P = 0.001, P = 0.011 and P = 0.017, respectively). Multivariate analysis using Cox proportional hazard model showed that neither intratumoral LVI nor peritumoral LVI was an independent prognostic factor of overall survival. The results of this study demonstrated that intratumoral as well as peritumoral LVI was associated with lymph node metastasis and adverse outcome in colorectal cancer.

Association of clinicopathological features with UbcH10 expression in colorectal cancer

PURPOSE

UbcH10 is the cancer-related E2 ubiquitin-conjugating enzyme, and its overexpression has been demonstrated in a variety of malignancies. The aim of this study is to investigate the association of UbcH10 gene expression with the carcinogenesis and tumor progression of colorectal cancer.

METHODS

The expression levels of UbcH10 in human malignant colorectal carcinoma tissues and their adjacent normal tissues were examined using real-time quantitative RT-PCR and immunohistochemical analysis. The correlations of UbcH10 expression to the clinicalpathologic characteristics of the colorectal cancer were analyzed. Cell proliferation and Matrigel invasion assays were performed in HT-29 cells transfected with UbcH10 expression plasmid pcDNA3.1-UbcH10, UbcH10 RNA interference vector pUbcH10-RNAi as well as their control vectors.

RESULTS

Our study demonstrated that the expression of UbcH10 in colorectal carcinoma tissues was significantly higher than that in non-cancerous tissues (P < 0.01), and the UbcH10 overexpression was related to the degree of tumor differentiation and lymph node metastasis of colorectal cancer patients (P < 0.05). In vitro, the overexpression of UbcH10 promoted cell proliferation and tumor invasiveness, but the downregulation of UbcH10 expression significantly reduced the growth rate and the invasiveness activity of tumor cell line.

CONCLUSIONS

Our study suggests that the overexpression of UbcH10 gene plays a critical role in the carcinogenesis and tumor progression of colorectal cancer. It may be a new marker in diagnosis and prognosis of colorectal cancer, and the inhibition of UbcH10 may be a therapeutic potential for the treatment of colorectal cancer.

VEGF-D deficiency in mice does not affect embryonic or postnatal lymphangiogenesis but reduces lymphatic metastasis

Vascular endothelial growth factor-D (VEGF-D) is one of the two ligands of the VEGFR-3 receptor on lymphatic endothelial cells. Gene-silencing studies in mice and Xenopus tadpoles recently showed that the role of endogenous VEGF-D in lymphatic development is moderate. By contrast, exogenous VEGF-D is capable of stimulating lymphangiogenesis. Nonetheless, its endogenous role in pathological conditions remains largely unknown. Hence, we reassessed its role in disease, using Vegf-d(null) mice. Vegf-d(null) mice were generated that, under physiological conditions, displayed normal embryonic and postnatal lymphangiogenesis and lymphatic remodelling, efficient lymphatic functioning and normal health. Vegf-d(null) mice also reponded normally in models of skin wound healing and healing of infarcted myocardium, despite enhanced expression of VEGF-D in these models in wild-type mice. In contrast, Vegf-d(null) mice displayed reduced peritumoral lymphangiogenesis and lymph node metastasis in an orthotopic pancreatic tumour model. Together, our data indicate that endogenous VEGF-D in mice is dispensible for lymphangiogenesis during development, in postnatal and adult physiology and in several pathological conditions, but significantly contributes to lymphatic metastasis.

Microvessel density and the association with single nucleotide polymorphisms of the vascular endothelial growth factor receptor 2 in patients with colorectal cancer

The measurement of microvessel density (MVD) is a widely accepted method for assessing the neoangiogenetic activity in neoplasia. The aim of the present study was to compare MVD with single nucleotide polymorphisms (SNPs) in the vascular endothelial growth factor receptor (VEGFR)-1 and VEGFR-2 genes and, furthermore, with quantitative measurements of the receptors in colorectal cancer (CRC) tissue. Prognosis was also assessed. Blood and tissue were collected from 110 patients surgically resected for CRC. SNPs were analysed from genomic DNA by polymerase chain reaction. MVD was assessed by immunohistochemistry using CD34 and CD105 combined with caldesmon in order to identify also immature vessels. Microvessels were counted in three fields of vision, and the mean MVD was used for statistical analysis. The VEGFR-2 1192 C/T and -604 T/C SNPs were associated with the MVD assessed by CD105. The median MVD score for the 1192 CC genotype was significantly lower compared to the CT + TT genotypes (p = 0.002). The median MVD score for the -604 CC genotype was significantly higher compared to the TT + TC genotypes (p = 0.009). A possible association, although non-significant, was demonstrated for the CD34-positive microvessels. The 1192 CC genotype and the -604 TT + TC genotypes correlated with improved survival. This is the first report on correlations between SNPs in the VEGF receptor genes and MVD in patients with CRC. Associations were shown between two SNPs in the VEGFR-2 gene and the CD105-positive microvessels indicating an impact on neoangiogenesis. Moreover, an association between the SNPs and survival was demonstrated. The clinical implications of these findings need further investigations.

Irinotecan therapy and molecular targets in colorectal cancer: a systemic review

Irinotecan is the second line chemotherapy for advanced stage colorectal cancer (CRC) after failure of first line chemotherapy with oxaliplatin and 5-fluorouracil. The aim of this review is to analyse the data on irinotecan as second line chemotherapy for advanced CRC and the potential roles of the molecular markers, p53 and vascular endothelial growth factor (VEGF) in the management of advanced CRC. Thus, the English literature from 1980 to 2008 concerning irinotecan, p53, VEGF and CRC was reviewed. On review, Phase II and III clinical trials showed that irinotecan improves pain-free survival, quality of life, 1-year survival, progression-free survival and overall survival in advanced CRC. p53 and VEGF were expressed in CRC and had a predictive power of aggressive clinical behaviour in CRC. Irinotecan sensitizes p53 wild type, mutant and null cells to Fas-mediated cell apoptosis in CRC cells. Wild type p53 cells were more sensitive to irinotecan than mutated p53. Irinotecan has an anti-VEGF effect inhibiting endothelial cell proliferation, increasing apoptosis and reducing microvascular density which is only limited by irinotecan toxicity levels. To conclude, irinotecan improves the patient's quality of life and the survival rates of patients with advanced CRC. p53 and VEGF status of the patients' tumour is likely to affect the responsiveness of CRC to irinotecan. It is recommended that studies of the expression of these molecular markers in relation to chemo-responsiveness of irinotecan should be carried out for better management of patients with advanced CRC.