No association of vascular endothelial growth factor-A (VEGF-A) and VEGF-C expression with survival in patients with gastric cancer

Optimal management of resected gastric cancer

Although advances in medical treatment for gastric cancer (GC) have been made, surgery remains the mainstay of cure for patients with localized disease. Improvement in surgical modalities leads to increased chance of cure for resected patients, but a non-negligible number of patients eventually relapse. On this basis, it has been hypothesized that the addition of complementary systemic or local treatments (such as chemotherapy and radiotherapy) could help in improving patients' survival by reducing the risk of recurrence. Several studies have tried to identify the best approach in localized GC: some of them have assessed the role of perioperative chemotherapy [CT] with different drug combinations, while others have focused on the benefit obtained by addition of radiotherapy, whose role is still under investigation. In particular, the role of chemoradiotherapy, both in adjuvant and neoadjuvant settings, is still uncertain. In the last few years, several clinicopathological and molecular factors have been investigated and identified as potential prognostic markers in GC. Many of these factors could have influenced the outcome of patients receiving combined treatments in the abovementioned studies. Patients have not been generally distinguished by the site of disease (esophageal, gastric and junctional cancers) and surgical approach, making data difficult to be interpreted. The purpose of this review was to shed light on these highly controversial topics.

Proposed Molecular and miRNA Classification of Gastric Cancer

Gastric cancer (GC) is a common malignant neoplasm worldwide and one of the main cause of cancer-related deaths. Despite some advances in therapies, long-term survival of patients with advanced disease remains poor. Different types of classification have been used to stratify patients with GC for shaping prognosis and treatment planning. Based on new knowledge of molecular pathways associated with different aspect of GC, new pathogenetic classifications for GC have been and continue to be proposed. These novel classifications create a new paradigm in the definition of cancer biology and allow the identification of relevant GC genomic subsets by using different techniques such as genomic screenings, functional studies and molecular or epigenetic characterization. An improved prognostic classification for GC is essential for the development of a proper therapy for a proper patient population. The aim of this review is to discuss the state-of-the-art on combining histological and molecular classifications of GC to give an overview of the emerging therapeutic possibilities connected to the latest discoveries regarding GC.

Correlations between VEGF-A expression and prognosis in patients with gastric adenocarcinoma

Angiogenesis induced by vascular endothelial growth factor A (VEGF-A) plays a critical role in tumor growth and metastasis. The study aimed to evaluate the expression of VEGF-A in gastric adenocarcinoma and investigate its correlations with tumor clinicopathological features and prognostic significance. VEGF-A expression was detected by immunohistochemistry on a tissue microarray containing 90 pairs of human gastric adenocarcinoma and paracancerous tissues. Levels of VEGF-A in gastric adenocarcinoma were significantly higher than those in paracancerous tissues (P=0.018). Furthermore, the result was coincident with that of human gastric adenocarcinoma xenografts in nude-mice (P<0.01). In addition, the VEGF-A expression was positive correlation with TNM stage (P=0.047), tumor size (P=0.028), positive lymph nodes (P=0.002) and lymphovascular invasion (P=0.001). Finally, Kaplan-Meier survival analysis showed that VEGF-A up-regulation indicated a poor prognosis for overall survival (P=0.039). In conclusions, VEGF-A may be used as a biomarker for evaluating both the biological behavior of tumor and the prognosis in patients with gastric adenocarcinoma.

Biomarker analyses in REGARD gastric/GEJ carcinoma patients treated with VEGFR2-targeted antibody ramucirumab

BACKGROUND

Angiogenesis inhibition is an important strategy for cancer treatment. Ramucirumab, a human IgG1 monoclonal antibody that targets VEGF receptor 2 (VEGFR2), inhibits VEGF-A, -C, -D binding and endothelial cell proliferation. To attempt to identify prognostic and predictive biomarkers, retrospective analyses were used to assess tumour (HER2, VEGFR2) and serum (VEGF-C and -D, and soluble (s) VEGFR1 and 3) biomarkers in phase 3 REGARD patients with metastatic gastric/gastroesophageal junction carcinoma.

METHODS

A total of 152 out of 355 (43%) patients randomised to ramucirumab or placebo had ⩾1 evaluable biomarker result using VEGFR2 immunohistochemistry or HER2, immunohistochemistry or FISH, of blinded baseline tumour tissue samples. Serum samples (32 patients, 9%) were assayed for VEGF-C and -D, and sVEGFR1 and 3.

RESULTS

None of the biomarkers tested were associated with ramucirumab efficacy at a level of statistical significance. High VEGFR2 endothelial expression was associated with a non-significant prognostic trend toward shorter progression-free survival (high vs low HR=1.65, 95% CI=0.84,3.23). Treatment with ramucirumab was associated with a trend toward improved survival in both high (HR=0.69, 95% CI=0.38, 1.22) and low (HR=0.73, 95% CI=0.42, 1.26) VEGFR2 subgroups. The benefit associated with ramucirumab did not appear to differ by tumoural HER2 expression.

CONCLUSIONS

REGARD exploratory analyses did not identify a strong potentially predictive biomarker of ramucirumab efficacy; however, statistical power was limited.

Molecular classification of gastric cancer: Towards a pathway-driven targeted therapy

Gastric cancer (GC) is the third leading cause of cancer mortality worldwide. Although surgical resection is a potentially curative approach for localized cases of GC, most cases of GC are diagnosed in an advanced, non-curable stage and the response to traditional chemotherapy is limited. Fortunately, recent advances in our understanding of the molecular mechanisms that mediate GC hold great promise for the development of more effective treatment strategies. In this review, an overview of the morphological classification, current treatment approaches, and molecular alterations that have been characterized for GC are provided. In particular, the most recent molecular classification of GC and alterations identified in relevant signaling pathways, including ErbB, VEGF, PI3K/AKT/mTOR, and HGF/MET signaling pathways, are described, as well as inhibitors of these pathways. An overview of the completed and active clinical trials related to these signaling pathways are also summarized. Finally, insights regarding emerging stem cell pathways are described, and may provide additional novel markers for the development of therapeutic agents against GC. The development of more effective agents and the identification of biomarkers that can be used for the diagnosis, prognosis, and individualized therapy for GC patients, have the potential to improve the efficacy, safety, and cost-effectiveness for GC treatments.

Fentanyl inhibits the progression of human gastric carcinoma MGC-803 cells by modulating NF-κB-dependent gene expression in vivo

Fentanyl is widely used to treat acute and chronic pain. Previous in vitro studies by the present authors demonstrated that fentanyl inhibits the progression of the MGC-803 human gastric carcinoma cell line by affecting apoptosis-related genes, including nuclear factor-kappa B (NF-κB) and phosphatase and tensin homolog. In the present study, the effects of fentanyl on NF-κB-dependent gene expression were investigated in vivo. Nude mice were inoculated with an MGC-803 cell suspension, and mice that developed subcutaneous tumors measuring >1.0×1.0 cm were selected for study. Mice were administered intraperitoneal injections of fentanyl (0.05 mg/kg, group F1; 0.1 mg/kg, group F2; 0.2 mg/kg, group F3; and 0.4 mg/kg, group F4) for 14 consecutive days. Non-fentanyl-treated mice (group C) and normal saline-treated mice (group N) served as the control groups. Tumor growth was monitored by calculating the time-shift of the growth curve. Morphological changes were also observed using microscopy. The expression of NF-κB, B-cell lymphoma-2 (Bcl-2), B-cell associated X protein (Bax), vascular endothelial growth factor-A (VEGF-A) and matrix metalloproteinase-9 (MMP-9) in the subcutaneous tumor tissue was also analyzed by reverse transcription-polymerase chain reaction and western blot analysis, and confirmed using immunohistochemistry. The relative tumor volumes of groups F1, F2, F3 and F4 were significantly reduced compared with groups C and N. Furthermore, subcutaneous tumor cells exhibited nuclear swelling, chromatin condensation, reduced chromatin and nuclear fragmentation in the F1, F2, F3 and F4 groups. The number of NF-κB⁺, Bcl-2⁺, VEGF-A⁺ and MMP-9⁺ subcutaneous tumor cells was reduced, whereas the number of Bax⁺ cells was increased in the F1, F2, F3 and F4 groups. Additionally, in these groups, tumor expression of NF-κB, Bcl-2, VEGF-A and MMP-9 transcripts and proteins was downregulated, while Bax messenger RNA and protein expression levels were upregulated. The results revealed that fentanyl inhibits the growth of subcutaneous human gastric carcinoma tumors in mice. Therefore, it could be hypothesized that this antineoplastic activity may result from the inhibition of NF-κB activation, suppression of downstream VEGF-A and MMP-9 expression, and normalization of the pro-apoptotic Bax/Bcl-2 ratio.

The different role of intratumoral and peritumoral lymphangiogenesis in gastric cancer progression and prognosis

Background

Tumor-induced lymphangiogenesis plays a crucial role in metastasis and tumor progression. However, the significance of intratumoral lymphovascular density (I-LVD) and peritumoral lymphovascular density (P-LVD) has been controversial in gastric cancer. The purpose of this study was to investigate the differences of clinicopathologic characteristics with respect to I-LVD and P-LVD in gastric cancer.

Methods

Samples of I-LVD and P-LVD from 66 patients who had undergone radical gastrectomy for gastric cancer were assessed after staining with D2-40, an immunostaining marker for lymphatic endothelium. The mean number of lymphatic vessels in three hotspots was calculated in intratumoral and peritumoral areas.

Results

The peritumoral lymphatics were enlarged with dilated lumens compared to the intratumoral lymphatics. I-LVD was positively correlated with diffuse gastric cancer subtype, tumor stage, lymphovascular invasion, tumor node metastasis stage, and overall survival (P <0.05). P-LVD was associated with lymphovascular invasion, node stage, and disease-free survival (P <0.05).

Conclusions

We conclude that P-LVD had an important role in lymph node metastasis, while I-LVD was more associated with depth of tumor invasion. However, both LVDs contributed to gastric cancer progression and prognosis.

Disrupted Balance of MMPs/TIMPs in Gastric Carcinogenesis-Paradoxical Low MMP-2 Expression in Tumor and Stromal Compartments as a Potential Marker of Unfavorable Outcome

The aim of the study was to find correlations between MMP/TIMP reactivity and the expression of angiogenic factors, and relationships between these parameters and clinicopathological features of gastric cancer patients. Receiver Operating Characteristic curve analysis was used to find cut-off points that enabled fair decision-making in survival analysis. Low levels of MMP-2 expression in tumor and stromal compartments were significantly associated with poor prognosis-the probability that a patient would die within 60 months of surgery if their MMP-2 was low, and was about 0.8 in both neoplastic and stromal compartments.

Prognostic value of vascular endothelial growth factor A expression in gastric cancer: a meta-analysis

Vascular endothelial growth factor A (VEGF-A) is considered as a prime mediator of angiogenesis and has been implicated in carcinogenesis and metastasis. Various studies examined the relationship between VEGF-A overexpression with the clinical outcome in patients with gastric cancer, but yielded conflicting results. Electronic databases updated to September 2013 were searched to find relevant studies. A meta-analysis was conducted with eligible studies which quantitatively evaluated the relationship between VEGF-A overexpression and survival of patients with gastric cancer. Survival data were aggregated and quantitatively analyzed. We performed a meta-analysis of 20 studies that evaluated the correlation between VEGF-A overexpression and survival in patients with gastric cancer. Combined hazard ratios suggested that VEGF-A overexpression had an unfavorable impact on overall survival (OS) (hazard ratio [HR] = 1.57; 95% confidence interval [CI], 1.30–1.84) and disease-free survival (DFS) (HR = 1.85; 95% CI, 1.39–2.32) in patients with gastric cancer. No significant heterogeneity (P = 0.487) was observed among 16 studies for OS and among 7 studies for DFS (P = 0.435). VEGF-A overexpression indicates a poor prognosis for overall survival and disease-free survival in patients with gastric cancer.

VEGF-A clinical significance in gastric cancers: immunohistochemical analysis of a wide Italian cohort

PURPOSE

The clinical significance of VEGF-A expression in gastric cancer (GC) has been reported with contradicting results. We analyzed the expression and clinical significance of VEGF-A in a wide Italian cohort of GC specimens.

METHODS

VEGF-A expression was tested by immunohistochemistry in 507 patients with GC of all clinical stages. The impact of VEGF-A on overall survival (OS) was evaluated in conjunction with clinical and pathological parameters.

RESULTS

In the Italian cohort we studied VEGF-A was not an independent prognostic factor neither at the univariate nor at multivariate analysis.

CONCLUSIONS

Although frequently expressed, in our study VEGF-A was not able to discriminate between groups of patients with different risk.

Clinicopathologic significance of nuclear factor-κB and vascular endothelial growth factor expression in advanced gastric cancer patients

BACKGROUND

Nuclear factor-κB (NF-κB) and vascular endothelial growth factor (VEGF) are involved in cell proliferation, invasion, angiogenesis, and metastasis. The principal objective of this study was to assess the prognostic significance of NF-κB and VEGF expression in gastric cancer.

METHODS

Tumor tissues of 154 patients with gastric cancer, all of whom underwent potentially curative resection, were immunohistochemically evaluated using monoclonal antibodies against NF-κB and VEGF.

RESULTS

The positivity rates of NF-κB and VEGF staining were 44.2% and 39.6%, respectively. NF-κB expression in tumor tissues was significantly correlated with VEGF expression (p < 0.001). VEGF expression was related to Lauren's classification (p = 0.002), differentiation (p = 0.043), depth of invasion (p = 0.005), carcinoembryonic antigen expression (p = 0.032), and stage (p = 0.026). Univariate analysis demonstrated that NF-κB expression was significantly related to both the 5-year disease-free survival (65.2% vs. 46.4%, p = 0.007) and the 5-year overall survival (60.0% vs. 42.5%, p = 0.014). Multivariate analysis verified that NF-κB was independently associated with disease-free survival (hazard ratio: 2.082, p = 0.005) and overall survival (hazard ratio: 1.841, p = 0.008).

CONCLUSION

NF-κB expression in tumor tissue is associated with poor survival in gastric cancer patients.

Protein kinase B phosphorylation correlates with vascular endothelial growth factor A and microvessel density in gastric adenocarcinoma

OBJECTIVE

The signalling molecule protein kinase B (Akt) modulates many cellular processes. Phosphatidylinositol 3-kinase (PI3K)/Akt signalling pathways play important roles in tumour angiogenesis. The aim of this study was to determine the role of phosphorylated Akt (pAkt) in angiogenesis and its correlation with vascular endothelial growth factor (VEGF)-A in gastric adenocarcinoma.

METHODS

Tumour tissue and matched healthy gastric mucosa were obtained from patients undergoing surgical resection of gastric adenocarcinoma. Akt and pAkt were detected via Western blotting. VEGF-A, pAkt and CD34 were examined by immunohistochemistry.

RESULTS

Akt and pAkt protein levels were significantly higher in gastric cancer tissue than in normal tissue (n = 48 patients). Positive VEGF-A immunostaining was significantly associated with pAkt immunostaining. Microvessel density was correlated with both VEGF-A and pAkt positivity.

CONCLUSIONS

Phosphorylated Akt and VEGF-A are involved in angiogenesis of gastric adenocarcinoma, and Akt activation may contribute to angiogenesis via VEGF-A upregulation. The PI3K/Akt/VEGF signalling pathway may be involved in gastric adeno carcinoma.

Prognostic value of vascular endothelial growth factor expression in resected gastric cancer

BACKGROUND AND AIMS

Vascular endothelial growth factor (VEGF) is a potential prognostic biomarker for patients with resected gastric cancer. However, its role remains controversial. The objective of this study was to conduct a systematic review and meta-analysis of published literature.

METHODS

Relevant literature was identified using Medline and survival data from published studies were collected following a methodological assessment. Quality assessment of eligible studies and meta-analysis of hazard ratio (HR) were performed to review the correlation of VEGF overexpression with survival and recurrence in patients with gastric cancer.

RESULTS

Our meta-analysis included 44 published studies with 4,794 resected patients. VEGF subtype for the prediction of overall survival (OS) included tissue VEGF (HR=2.13, 95% CI 1.71-2.65), circulating VEGF (HR=4.22, 95% CI 2.47-7.18), tissue VEGF-C (HR=2.21, 95% CI 1.58-3.09), tissue VEGF-D (HR=1.73, 95% CI 1.25-2.40). Subgroup analysis showed that HRs of tissue VEGF for OS were, 1.78 (95% CI 0.90-3.51) and 2.31 (95% CI 1.82-2.93) in non-Asians and Asians, respectively. The meta-analysis was also conducted for disease free survival (DFS) and disease specific survival (DSS).

CONCLUSION

Positive expression of tissue VEGF, circulating VEGF, VEGF-C and VEGF-D were all associated with poor prognosis in resected gastric cancer. However, VEGF demonstrated no significant prognostic value for non-Asian populations. Circulating VEGF may be better than tissue VEGF in predicting prognosis.

Overexpression of both VEGF-A and VEGF-C in gastric cancer correlates with prognosis, and silencing of both is effective to inhibit cancer growth

BACKGROUND

Vascular endothelial growth factor (VEGF)-A and VEGF-C are two important molecules involving in tumor development and metastasis via angiogenesis and lymphangiogenesis. However, the combined effect of VEGF-A and VEGF-C on the growth of gastric cancer (GC) is not clear.

METHODS

The correlations of VEGF-A and VEGF-C expressions with clinicopathologic parameters and prognosis were evaluated in patients with GC. Furthermore, lentivirus-mediated RNA interfering (RNAi) targeting VEGF-A and/or VEGF-C was employed to silence their expressions in SGC7901 GC cell line. Cell proliferation and apoptosis were measured in vitro. Suppressive effect lentivirus-mediated VEGF-A and/or VEGF-C silencing on GC growth was evaluated in GC bearing mice.

RESULTS

The patients with high expression of both VEGF-A and VEGF-C (A+C+) had larger tumor size, higher peritumoral lymphatic vessel density(P-LVD), microvessel density(MVD), lymphatic vessel invasion (LVI), lymph node(LN) metastasis, and worse prognosis than those with low expression of both VEGF-A and VEGF-C (P<0.05). Lentivirus-mediated RNAi significantly reduced the mRNA and protein expression of VEGF-A and VEGF-C in the SGC7901 cells. The Lenti-miRNA-VEGF-A+VEGF-C significantly inhibited the cell proliferation and tumor growth, compared with Lenti-miRNA-VEGF-A or Lenti-miRNA-VEGF-C (P<0.05). In addition, Lenti-miRNA- VEGF-A+VEGF-C markedly lowered the tumor size in vivo in comparison with Lenti-miRNA-VEGF-A or Lenti-miRNA-VEGF-C (P<0.05).

CONCLUSION

Expressions of both VEGF-A and VEGF-C predict worse prognosis of GC patients. Combined silencing of VEGF-A and VEGF-C markedly suppresses cancer growth than silencing of VEGF-A or VEGF-C. Thus, to inhibit the expressions of VEGF-A and VEGF-C may become a novel strategy for the treatment of GC.

Molecular mechanisms of lymphatic metastasis in solid tumors of the gastrointestinal tract

Tumor cell dissemination from the primary tumor site to distant organs is one of the characteristic properties of malignant tumors and represents a crucial step in the progression of disease. Although the pattern of spread may vary in different types of carcinomas, dissemination via the lymphatic system represents a common event in metastasis. The extent of lymph node metastasis is one of the major determinants for the prognosis of patients with gastrointestinal carcinomas and guides the therapeutically management. During the last decades, significant attention has been given to the molecular mechanisms that control lymphatic metastasis. The process of lymphangiogenesis has come into the focus. Lymphangiogenesis, the formation of newly lymphatics, comprises a series of complex cellular events and is controlled by a balance between pro- and anti-lymphangiogenic signals. This article will briefly describe the lymphatic system and then provide an overview of the molecular players involved in tumor lymphangiogenesis.

Prognostic significance of vascular endothelial growth factor immunohistochemical expression in gastric cancer: a meta-analysis

Vascular endothelial growth factor (VEGF) is considered as a prime mediator of angiogenesis, and has been implicated in carcinogenesis and metastasis. Various studies examined the relationship between VEGF protein overexpression with the clinical outcome in patients with gastric cancer, but yielded conflicting results. The prognostic significance of VEGF overexpression in gastric cancer remains controversial. Electronic databases updated to July 2011 were searched to find relevant studies. A meta-analysis was conducted with eligible studies which quantitatively evaluated the relationship between VEGF overexpression and survival of patients with gastric cancer. Survival data were aggregated and quantitatively analyzed. We performed a meta-analysis of 30 studies (n = 3,999 patients) that evaluated the correlation between VEGF overexpression detected by immunohistochemistry and survival in patients with gastric cancer. Combined hazard ratios suggested that VEGF-A overexpression had an unfavorable impact on overall survival (OS) (HR [hazard ratio] = 1.49, 95 % CI [confidence interval]: 1.22-1.77) and disease free survival (DFS) (HR = 1.85, 95 % CI: 1.38-2.32) in patients with gastric cancer. However, VEGF-C overexpression did not significantly correlate with OS (HR = 1.24, 95 % CI: 0.92-1.56) or DFS (HR = 1.15, 95 % CI: 0.78-1.52). VEGF-D is an unfavorable indicator of OS (HR = 1.68, 95 % CI: 1.02-2.34) and DFS (HR = 1.88, 95 % CI: 1.07-2.70) in patients with gastric cancer. VEGF-A and VEGF-D overexpression indicated a poor prognosis for patients with gastric cancer. VEGF-C overexpression was not associated with poor prognosis in patients with gastric cancer. The prognostic value of VEGF on survival still needs further larger prospective trials to be confirmed.

Potential prognostic and therapeutic role for angiogenesis markers in laryngeal carcinoma

Angiogenesis is a hallmark of cancer, fundamental to its growth. The 'angiogenic switch' occurs when pro-angiogenic factors are not balanced by anti-angiogenic factors. A correlation between angiogenic properties and oncological prognosis (for laryngeal squamous cell carcinoma (LSCC) too) was first hypothesized in the 1990s. An exhaustive literature review was performed to investigate available data on angiogenesis markers and their biological role and therapeutic potential in LSCC. The prognostic significance of microvascular density in LSCC was investigated with endothelial targets, e.g. CD105, CD34, and CD31. Epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), VEGF receptor 2, angiogenin, hypoxia-inducible factor 1, and other biological markers were also studied. Only anti-EGFR therapy has been approved by the USFood and Drug Administration (FDA) for head and neck carcinoma in recent years, while several agents interfering with VEGF and its receptors are being studied. Experimental findings indicate that anti-CD105 monoclonal antibodies efficiently inhibit tumor angiogenesis. There are two main ways to approach the vascular profile of solid malignancies: by inhibiting new vessel formation (anti-angiogenic therapy) or selectively damaging neoplastic vessels (vascular targeting therapy). In advanced LSCC, both these strategies seem promising and warrant further preclinical and clinical investigation.

Prognostic significance of vascular endothelial growth factor expression in gastric carcinoma: a meta-analysis

PURPOSE

The purpose of this study was to comprehensively and quantitatively summarize available evidences for the use of VEGF protein to evaluate the clinicopathological and prognostic role of VEGF expression in Asian patients with gastric cancer.

METHOD

Searches were applied to MEDLINE, EMBASE, and the Cochrane Library databases until June 2010, without language restrictions. A meta-analysis was performed to clarify the impact of VEGF expression on clinicopathological parameters or over survival (OS) in gastric cancer.

RESULTS

Our combined results showed that VEGF expression in Asian patients with gastric cancer was significantly higher in the case-control studies (1,194 patients and 1,618 controls) (odds ratio [OR] = 112.41, 95% confidence interval [CI] = 64.12-197.06). All the analyses estimated favored a stronger link between the high VEGF expression and the poor 5-year overall survival (1,236 patients) (risk ratio [RR] = 2.45, 95% CI = 2.11-2.83, P = 0.000). When stratifying the studies by the pathological variables, the depth of invasion (3,094 patients) (OR = 1.95, 95% CI = 1.40-2.71, P = 0.000), lymph node metastasis (3,240 patients) (OR = 1.82, 95% CI = 1.29-2.57, P = 0.001), distant metastasis (1,980 patients) (OR = 2.76, 95% CI = 1.22-6.25, P = 0.015), vascular invasion (1,803 patients) (OR = 2.61, 95% CI = 2.09-3.27, P = 0.000), and TNM stage (1,819 patients) (OR = 1.92, 95% CI = 1.57-2.36, P = 0.000) provided significant prognostic information.

CONCLUSION

Our results indicate that VEGF can potently predict the overall survival in Asian patients with gastric cancer. Importantly, VEGF may be converted from candidate to the routine clinical setting for clinicians to predict the outcome of single patient with gastric carcinoma.

Role of endoglin and VEGF family expression in colorectal cancer prognosis and anti-angiogenic therapies

Colorectal cancer (CRC) is one of the cancer models and most of the carcinogenic steps are presently well understood. Therefore, successful preventive measures are currently used in medical practice. However, CRC is still an important public health problem as it is the third most common cancer and the fourth most frequent cause of cancer death worldwide. Nowadays, pathologic stage is a unique and well-recognized prognostic indicator, however, more accurate indicators of the biologic behavior of CRC are expected to improve the specificity of medical treatment. Angiogenesis plays an important role in the growth and progression of cancer but its role as a prognostic factor is still controversial. Probably the most important clinical implication of tumor angiogenesis is the development of anti-angiogenic therapy. The goal of this review is to critically evaluate the role of angiogenic markers, assessed by either endoglin-related microvessel density or expression of vascular endothelial growth factor family members in the CRC setting and discuss the role of these angiogenic markers in anti-angiogenic therapies.

Collagens at a glance

Background

The prognosis of gastric cancer patients is difficult to predict because of defects in establishing the surgical-pathological features. Cancer-associated fibroblasts (CAFs) have been found to play prominent role in promoting tumor growth, invasion and metastasis. Thus raises the hypothesis that the extent of CAFs prevalence may help to establish the prognosis of gastric cancer patients.

Methods

Immunochemistry and realtime-PCR experiments were carried out to compare the expression of proteins which are specific markers of CAFs or secreted by CAFs in the tumor and normal tissue specimens. The extent of CAFs' prevalence was graded according to immunochemical staining, and correlation was further analyzed between CAFs' prevalence and other tumor characteristics which may influence the prognosis of gastric cancer patients.

Results

Nearly 80 percent of normal gastric tissues were negative or weak positive for CAFs staining, while more than 60 percent of gastric cancer tissues were moderate or strong positive for CAFs staining. Realtime-PCR results also showed significant elevated expression of FAP, SDF-1 and TGF-β1 in gastric cancer tissues compared to normal gastric tissues. Further analysis showed that CAFs' prevalence was correlated with tumor size, depth of the tumor, lymph node metastasis, liver metastasis or peritoneum metastasis.

Conclusions

Reactive cancer associated fibroblasts (CAFs) were frequently accumulated in gastric cancer tissues, and the prevalence of CAFs was correlated with tumor size, depth of the tumor and tumor metastasis, thus give some supports for establishing the prognosis of the gastric cancer patients.