The expression of vascular endothelial growth factor-C correlates with lymphatic microvessel density and lymph node metastasis in prostate carcinoma: An immunohistochemical study

Morphologic Pattern, Frequency, and Spatial Distribution of Lymphovascular Invasion Foci in Radical Prostatectomy Specimens

Introduction. Lymphovascular invasion (LVI) is an adverse pathological finding in radical prostatectomy (RP) specimens associated with increased risk of metastatic disease. Its variable incidence may be attributed to underreporting. We characterized the location, quantity, and morphology of LVI foci in RP specimens and assessed the relationship between LVI and cribriform and intraductal carcinoma and metastatic risk. Methods. Two pathologists reviewed retrospectively 54 RP specimens reported as positive for LVI. Ambiguous cases were confirmed by immunostaining for ERG, CD31 and D2-40. Results. In 4/54 (7.4%), LVI could not be confirmed. Main mimickers of LVI were retraction artifact and dislodged tumor cells. Based on our review, the most important criteria to distinguish LVI from its mimickers were a corrugated lining of vascular spaces, endothelial nuclei bulging into the lumen, and presence of proteinaceous material. The LVI frequency per case ranged from 1 to 109 (median 7.5). In 47/50 (94%) cases with LVI, the associated carcinoma comprised cribriform pattern and/or intraductal carcinoma. The most common morphology of LVI foci was cribriform, occurring in 43/50 specimens, representing 469/843 (56%) of LVI foci. Most LVI foci were intraprostatic and located at the carcinoma-stroma interface. Particularly the risk of bone metastases during follow-up was independently associated with higher frequency of LVI foci (P = .009). Conclusions. The detailed description of prostatic LVI, and awareness of their predominant location and morphology may help its identification and improve the diagnostic accuracy of LVI in pathology reporting. The clinical impact of LVI quantification in prostate cancer needs validation by further studies.

Does the Expression of Vascular Endothelial Growth Factor (VEGF) and Bcl-2 Have a Prognostic Significance in Advanced Non-Small Cell Lung Cancer?

Lung cancer is the most common cause of mortality from malignant tumors worldwide. The five-year survival rate for people with advanced stages varies considerably, from 35.4% to 6.9%. The angiogenic potential of bcl2 is not well known, nor is the way in which tumor cells with excessive bcl2 expression affect VEGF production. Hypothetically, given that tumor growth, progression and metastasis are dependent on angiogenesis, the antiapoptotic effect is expected to form a link between these two molecules. The aim of this study was to evaluate the relationship between bcl-2 and VEGF expression, clinicopathological features and survival in 216 patients with advanced NSCLC. Archival tumor tissues were examined by immunohistochemistry for the expression of bcl-2 and VEGF. Immunoreactivity for bcl-2 was observed in 41.4% of NSCLCs, 51% of squamous and 34.8% of adenocarcinomas-expressed Bcl-2. There was an inverse correlation of mononuclear stromal reaction and bcl-2 expression in adenocarcinoma (p < 0.0005). A total of 71.8% NSCLCs were VEGF positive, 56% of squamous and 82.2% of adenocarcinomas. High level of VEGF expression was significantly associated with histology type (p = 0.043), low histology grade (p = 0.014), clinical stage IV (p = 0.018), smoking history (p = 0.008) and EGFR mutations (p = 0.026). There was an inverse correlation in the expression of Bcl-2 and VEGF in NSCLC patients (p = 0.039, r = -0.163). Two-year survival of patients with unresectable NSCLC was 39.3%, and 50% of patients were alive at 17 months. Our results demonstrated no difference in survival for patients in advanced NSCLC grouped by bcl-2 and VEGF status. Additionally, we observed an inverse correlation in the expression of Bcl-2 and VEGF in NSCLC and mononuclear reaction and bcl-2 expression in adenocarcinomas.

Expression of Claudin-4 and D2-40 and their significance in prostatic adenocarcinoma

BACKGROUND

Claudins are a clan of proteins that are the most important component of tight junctions. The claudin-4 expression has been linked to tumour cell invasion and progression in a variety of primary malignancies. Evaluation of lymphovascular density (LVD) correlates with tumour aggressiveness and may correlate with prognosis. D2-40 is a highly specific marker of lymphatic vessels.

AIMS

To evaluate the claudin-4 expression in relation to LVD by D2-40 expression and with clinicopathological parameters in prostatic adenocarcinoma.

SETTINGS AND DESIGN

Prospective study.

MATERIALS AND METHODS

39 cases of prostatic adenocarcinoma were taken, the D2-40 and claudin-4 immunohistochemical stains were performed and correlation was done with clinicopathological parameters.

STATISTICAL ANALYSIS USED

Statistical analyses such as mean, median, standard deviation, Mann-Whitney U test, Fischer exact test, Spearman's rank-order correlation coefficient, Chi-square test and T-test were used.

RESULTS

The claudin-4 expression was seen higher in cases with higher Gleason score but it was statistically non-significant (P = 0.778). The claudin-4 expression did not correlate with any clinicopathological parameters. LVD in the peritumoral area was significantly higher as compared to the intratumoral area (P = 0.005). Intratumoral LVD and perineural invasion were found to be statistically significant (P = 0.048).

CONCLUSION

The claudin-4 expression may correlate with adverse prognostic parameters. Higher lymphatic vessels can be responsible for the higher metastatic potential of prostatic adenocarcinomas.

Lymphatic vessels in cancer

The lymphatic system, composed of initial and collecting lymphatic vessels as well as lymph nodes that are present in almost every tissue of the human body, acts as an essential transport system for fluids, biomolecules and cells between peripheral tissues and the central circulation. Consequently, it is required for normal body physiology but is also involved in the pathogenesis of various diseases, most notably cancer. The important role of tumor-associated lymphatic vessels and lymphangiogenesis in the formation of lymph node metastasis has been elucidated during the last two decades, whereas the underlying mechanisms and the relation between lymphatic and peripheral organ dissemination of cancer cells are incompletely understood. Lymphatic vessels are also important for tumor-host communication, relaying molecular information from a primary or metastatic tumor to regional lymph nodes and the circulatory system. Beyond antigen transport, lymphatic endothelial cells, particularly those residing in lymph node sinuses, have recently been recognized as direct regulators of tumor immunity and immunotherapy responsiveness, presenting tumor antigens and expressing several immune-modulatory signals including PD-L1. In this review, we summarize recent discoveries in this rapidly evolving field and highlight strategies and challenges of therapeutic targeting of lymphatic vessels or specific lymphatic functions in cancer patients.

Detection and prognostic value of intratumoral and peritumoral lymphangiogenesis in colorectal cancer

Background

Colorectal cancer (CRC) with lymphatic invasion is one of the critical prognostic factors in lymph node metastasis. Lymphangiogenesis has a significant effect on lymphatic metastasis and tumor progression. However, the significance of intratumoral and peritumoral lymphangiogenesis has been controversial in CRC. The aim of this study is to investigate the different role of introtumoral and peritumoral lymphangiogenesis in CRC progression and prognosis.

Methods

Lymphangiogenesis of 120 CRC specimens, as measured by lymphatic vessel density (LVD), was examined by immunostaining for podoplanin, a lymphatic vessel-specific marker. The mean number of lymphatic vessels of three hotspots was measured in intratumoral and peritumoral areas as intratumoral LVD (LVDit) and peritumoral LVD (LVDpt), respectively. The association of LVDit and LVDpt with the clinicopathological findings and prognosis was investigated.

Results

Compared to the peritumoral lymphatics, the intratumoral lymphatics were small, collapsed and irregular. The mean LVDpt was higher than the mean LVDit (P<0.001). LVDit was positively correlated with tumor size (P=0.009), tumor histologic grade (P=0.023), and overall survival (P=0.036). LVDpt was correlated with lymph node metastasis (P<0.001), tumor stage (P=0.004), and overall survival (P=0.016).

Conclusions

LVDpt plays a prominent role in lymph node metastasis, whereas LVDit is more closely correlated with tumor growth and histopathological differentiation. Both LVDpt and LVDit contribute to CRC progression and prognosis.

LPA1/3 signaling mediates tumor lymphangiogenesis through promoting CRT expression in prostate cancer

Lysophosphatidic acid (LPA) is a bioactive lipid growth factor which is present in high levels in serum and platelets. LPA binds to its specific G-protein-coupled receptors, including LPA₁ to LPA₆, thereby regulating various physiological functions, including cancer growth, angiogenesis, and lymphangiogenesis. Our previous study showed that LPA promotes the expression of the lymphangiogenic factor vascular endothelial growth factor (VEGF)-C in prostate cancer (PCa) cells. Interestingly, LPA has been shown to regulate the expression of calreticulin (CRT), a multifunctional chaperone protein, but the roles of CRT in PCa progression remain unclear. Here we investigated the involvement of CRT in LPA-mediated VEGF-C expression and lymphangiogenesis in PCa. Knockdown of CRT significantly reduced LPA-induced VEGF-C expression in PC-3 cells. Moreover, LPA promoted CRT expression through LPA receptors LPA₁ and LPA₃, reactive oxygen species (ROS) production, and phosphorylation of eukaryotic translation initiation factor 2α (eIF2α). Tumor-xenografted mouse experiments further showed that CRT knockdown suppressed tumor growth and lymphangiogenesis. Notably, clinical evidence indicated that the LPA-producing enzyme autotaxin (ATX) is related to CRT and that CRT level is highly associated with lymphatic vessel density and VEGF-C expression. Interestingly, the pharmacological antagonist of LPA receptors significantly reduced the lymphatic vessel density in tumor and lymph node metastasis in tumor-bearing nude mice. Together, our results demonstrated that CRT is critical in PCa progression through the mediation of LPA-induced VEGF-C expression, implying that targeting the LPA signaling axis is a potential therapeutic strategy for PCa.

Vascular endothelial growth factor suppresses dendritic cells function of human prostate cancer

Purpose

Prostate cancer (PCa) patients often have dendritic cell (DC) function defects, but the mechanism is not clear. The aim of this study was to detect the effect of vascular endothelial growth factor (VEGF) in mature DCs.

Patients and methods

In this study, we chose 30 PCa patients, 10 prostatic intraepithelial neoplasia (PIN) patients and 30 benign prostatic hyperplasia (BPH) patients, and compared the composition of peripheral blood T cells, the composition and function of local dendritic cells in prostate tissue, and the density of local VEGF.

Results

The results showed that the numbers of total DCs, mature and functional DCs, and CD4⁺ T cells were inhibited in PCa, and the inhibitory effect was enhanced with increased malignancy. In addition, the infiltration density of VEGF-positive cells was increased in PCa, and this increase was associated with an increased malignant degree of PCa. The inhibition of tumor immunity in patients with PCa is achieved by inhibiting the function of dendritic cells.

Conclusion

VEGF plays an important role in the inhibition of the maturation and function of dendritic cells, and this inhibition is gradually increased with an increasing malignant degree of PCa.

VEGF-C is positively associated with lymphangiogenesis and lymphatic metastasis in rectal cancer

Rectal cancer is a common malignancywith a less than 5-year postoperative survival rate. Although it often metastasizes via the lymph and blood, the detailed mechanism of this process remains unclear. This study investigated the relationship between vascular endothelial growth factor-C (VEGF-C) expression and lymphangiogenesis, as well as its relation to lymphatic metastasis of rectal cancer. To address this question, VEGF-C expression in rectal cancer and normal tissue adjacent to tumor was assessed by immunohistochemistry. The lymphatic endothelial cell-specific marker D2-40 was used to label lymphatic endothelial cells and the lymphatic vessel density (LVD) was subsequently quantified. As expected, the expression of VEGF-C in rectal cancer (75%) was significantly higher than in normal adjacent tissue (25%), and this level correlated with differentiation, Dukes stage, and lymph node metastasis, though not with sex or age. The LVD was higher in VEGF-C positive rectal cancer than in VEGF-C negative rectal cancer, and was also higher in lymphatic metastases than in non-lymphatic metastases. These results indicate that expression of VEGF-C may impact the prognosis of rectal cancer via its effect on the formation of new lymphatic vessels. This represents a significant advance in the study of the genesis and development of rectal cancer, and may have value in clinical care.

Molecular background of the regional lymph node metastasis of gastric cancer

Gastric cancer (GC) is one of the deadliest types of cancer in the world. Lymph node (LN) metastasis is a complex and malignant behavior of GC, involving a sequence of biological processes, including decreased adherence to adjacent cells, extracellular matrix (ECM) degradation and lymphatic channel permeation. LN metastasis is directly associated with the treatment response, local recurrence and long-term survival of patients with GC. Therefore, the molecular mechanisms of LN metastasis in GC development require further investigation. Recently, a large number of clinical studies have focused on the molecular mechanisms and biological markers of tumor invasion and metastasis. However, few articles have broadly summarized LN metastasis in GC, and the molecular mechanisms of LN metastasis are not yet fully understood. In the present review, the molecular mechanisms of LN metastasis in GC will be discussed, including the following aspects: Cell adhesion and movement, ECM degradation, new vessel formation, and molecular pattern differences between metastatic LNs and the primary tumor. This review may lead to a better understanding of LN metastasis in GC, and the identification of new diagnostic markers.

Tumor-associated antigen CAPERα and microvessel density in hepatocellular carcinoma

PURPOSE

CAPERα, a tumor-associated antigen, was identified from a cDNA clone with autoantibody from a patient with hepatocellular carcinoma (HCC). It has been implicated, by way of alternative splicing of VEGF pre-mRNA, in the regulation of microvessel formation in Ewing's sarcoma. In this study, we looked for possible association of alterations in CAPERα with microvessel density in HCC.

METHODS

Enzyme-linked immunosorbent assay using recombinant CAPERα as antigen were used to detect antibody against CAPERα. Immunohistochemistry (IHC) on liver sections was performed to analyze expression profiles of CAPERα, VEGF and CD34 in HCC and control tissues and was further used to assess the correlation of expression among CAPERα, VEGF and CD34 in HCC development.

RESULTS

Autoantibody to CAPERα was highest in HCC (22/76, 28.9%), not detected in prostate cancer (0/79) and at 3.4% (3/88) in breast cancer. In immunohistochemical analysis of grades II and III HCC tissues, significantly decreased immunostaining for CAPERα was observed and this correlated directly with decreased immunostaining for VEGF (R=0.534, P=0.0003). Using CD34 immunostaining for detecting newly formed microvessels, strong staining was observed in grades II and III HCC. Normal liver sections, all of which have high expression of CAPERα were totally negative for CD34 immunostaining. A significant inverse correlation was seen between CAPERα and CD34 immunostaining (R=-0.481, P=0.0012).

CONCLUSIONS

Decreased expression of CAPERα appears to be correlated with appearance of microvessels. It would be of interest to elucidate the cause of altered CAPERα since new formation of microvessels is important in progression of HCC.

Lymphangiogenesis in Classical Hodgkin Lymphoma - Preliminary Study with Clinicopathological Correlations

A role for lymphangiogenesis in metastatic breast and prostate cancers has been suggested recently. The relevance of lymphangiogenesis in cancer as a rule, and more specifically in classical Hodgkin lymphoma, is poorly understood in comparison with that of angiogenesis. In a preliminary (pilot) study we have investigated the role of lymphatic vessels growth in 19 cases of classical Hodgkin lymphoma stained with the D2-40 (podoplanin) antibody. In each case, three lymphatic vessels hot spots were scrutinized twice. Of the 57 hot spots thus identified, we chose 15 at random for photography, microvessel counting and image analysis. We determined the mean perimeter, surface area, major axis length and complexity factor for each hot spot and correlated them with clinical and biological features of classical Hodgkin lymphoma. No correlations were found with clinical features. No associations were noted with the standard immuno-markers of classical Hodgkin lymphoma. However, significant inverse correlations were shown with pRb, BAX and IκB-α expression. The mean lymphatic major axis length was inversely correlated with the complexity factor. Last, we carried out an additional clinicopathological correlation of the expression of pRb, BAX and IκB-α in a cohort of classical Hodgkin lymphoma patients previously published.

Tumor lymphangiogenesis and new drug development

Traditionally, tumor-associated lymphatic vessels have been regarded as passive by-standers, serving simply as a drainage system for interstitial fluid generated within the tumor. However, with growing evidence that tumors actively induce lymphangiogenesis, and that the number of lymphatic vessels closely correlates with metastasis and clinical outcome in various types of cancer, this picture has changed dramatically in recent years. Tumor-associated lymphatic vessels have now emerged as a valid therapeutic target to control metastatic disease, and the first specific anti-lymphangiogenic drugs have recently entered clinical testing. Furthermore, we are just beginning to understand the whole functional spectrum of tumor-associated lymphatic vessels, which not only concerns transport of fluid and metastatic cells, but also includes the regulation of cancer stemness and specific inhibition of immune responses, opening new venues for therapeutic applications. Therefore, we predict that specific targeting of lymphatic vessels and their function will become an important tool for future cancer treatment.

MicroRNA-101 suppresses migration and invasion via targeting vascular endothelial growth factor-C in hepatocellular carcinoma cells

MicroRNAs (miRNAs) are a class of non-coding RNAs 18-25 nucleotides in length, which play important roles in the regulation of cancer progression through gene silencing. miRNA (miR)-101 has been suggested to be associated with hepatocellular carcinoma (HCC). However, the detailed role of miR-101 in HCC metastasis and the underlying mechanism remain largely unclear. The present study demonstrated that the expression of miR-101 was significantly reduced in HCC tissues compared with that in matched normal adjacent tissues. miR-101 was also found to be downregulated in four HCC cell lines compared with its expression in a normal liver cell line. Vascular endothelial growth factor (VEGF)-C was further identified as a direct target of miR-101, and the protein expression of VEGF-C was downregulated by miR-101 in HepG2 HCC cells. Furthermore, the overexpression of miR-101 and the knockdown of VEGF-C significantly inhibited HepG2 cell migration and invasion, while restoration of VEGF-C reversed the inhibitory effect of miR-101 overexpression on HepG2 cell migration and invasion. Finally, the expression of VEGF-C was notably increased in HCC tissues and cell lines. These findings suggest that miR-101 exerts a suppressive effect on HCC cell migration and invasion, at least in part through the direct inhibition of VEGF-C protein expression. Therefore, the miR-101/VEGF-C axis may serve as a potential therapeutic target for HCC metastasis.

Prognostic Significance of Lymphatic Vessel Density Detected by D2-40 and Its Relation to Claudin-4 Expression in Prostatic Adenocarcinoma

Background Lymphovascular invasion is an important pathway of metastatic spread and regional lymph node metastasis is the major prognostic factor in prostatic adenocarcinoma. D2-40 is used to identify the lymphatic vessels and to assess the lymphatic vessel density (LVD). Expression of claudin-4 may be related to invasion and progression of carcinoma cells in several primary tumors. Aim To evaluate intra- and peritumoral LVD through immunohistochemical expression of D2-40 in relation to claudin-4 expression and clinicopathological parameters in prostatic adenocarcinoma. Materials and Methods Immunohistochemical staining procedure was performed on 53 paraffin-embedded blocks of radical prostatectomy specimens for prostatic adenocarcinoma using anti D2-40 and claudin-4 antibodies. Sections were evaluated for mean LVD in intratumoral and peritumoral tissues assessed by D2-40 expression. Results LVD in intratumoral tissues was significantly lower compared with peritumoral areas (P = .0001). Peritumoral mean LVD was significantly higher in cases with lymphovascular invasion (P = .041) and in cases with positive lymph node metastasis (P = .003) than intratumoral mean LVD. High claudin-4 expression was significantly correlated with high tumor grade (P = .0001), lymphovascular invasion (P = .006), and positive lymph node metastasis (P = .004). High claudin-4 expression was significantly associated with increased mean LVD in peritumoral tissues. Conclusion Increased peritumoral mean LVD in prostatic adenocarcinoma is associated with lymphovascular invasion and positive lymph node metastasis. High claudin-4 expression is associated with high tumor grade, lymphocascular invasion, positive lymph node metastasis, and high mean peritumoral LVD suggesting that D2-40 and claudin-4 may represent different mechanisms of lymphatic vessel invasion with both biomarkers is related to poor prognosis.

VEGF-C and VEGF-D expression and its correlation with lymph node metastasis in esophageal squamous cell cancer tissue

BACKGROUND

To explore vascular endothelial growth factor C (VEGF-C) and VEGF-D expression and its correlation with lymph node metastasis in esophageal squamous cell cancer (ESCC) tissue.

MATERIALS AND METHODS

Immunohistochemical methods were applied to detect the levels of VEGF-C and VEGF-D expression in 64 surgicall removal ESCC tissues, tissues adjacent to cancer and normal tissues, and the relationship between VEGF-C and VEGF-D expression and lymph node metastasis was analyzed.

RESULTS

Both VEGF-C and VEGF-D were expressed by varying degrees in esophageal cancer tissue, the tissue adjacent to cancer and normal tissue, and the positive expression rate went down successively. The positive expression rates of VEGF-C (59.4%) and VEGF-D (43.8%) in esophageal cancer tissue were significantly higher than in the tissue adjacent to cancer (34.4%, 15.6%) and normal tissue (20.3%, 12.5%), respectively, in which significant differences were manifested (p<0.01). Positive expression rates of VEGF-C and VEGF-D in esophageal cancers with lymph node metastasis were markedly higher than without such metastasis (p<0.01), while those in the tissue with TNM staging I~II were markedly lower than that with TNM staging III~IV (p<0.01).

CONCLUSIONS

Both VEGF-C and VEGF-D are highly expressed in ESCC tissue, which may be related to the lymph node metastasis of cancer cells. Hence, VEGF-C and VEGF-D can be clinically considered as important reference indexes of lymph node metastasis in esophageal cancer.

Clinical significance of COX-2, GLUT-1 and VEGF expressions in endometrial cancer tissues

OBJECTIVE

To analyze the clinical significance of COX-2, GLUT-1 and VEGF expressions in endometrial cancer tissues.

METHODS

One hundred and eight tissue samples from the patients with endometrial cancer enrolled in our hospital from August 2011 to July 2014 were selected, including 60 normal tissue samples (normal group), 60 neoplastic tissue samples (neoplastic group) and 60 cancer tissue samples (cancer group). All the samples were subjected to immunohistochemical assay to detect the expressions of COX-2, GLUT-1 and VEGF. The clinical data were also investigated for correlation analysis.

RESULTS

The positive rates of COX-2 in normal group, neoplastic group and cancer groups were 3.3%, 21.7% and 55.0% respectively. The positive rates of GLUT-1 in normal group, neoplastic group and cancer groups were 3.3%, 25.0% and 70.0% respectively. The positive rates of VEGF in normal group, neoplastic group and cancer groups were 1.7%, 23.3% and 63.3% respectively. With increasing stage of such cancer, decreasing degree of differentiation and lymphatic metastasis, the positive expression rates of COX-2, GLUT-1 and VEGF proteins were raised significantly (P<0.05). Spearman's correlation analysis showed that the expressions of COX-2 and GLUT-1 (r=0.207, P<0.05), COX-2 and VEGF (r=0.243, P<0.05), as well as GLUT-1 and VEGF (r=0.758, P<0.05) were positively correlated.

CONCLUSION

COX-2, GLUT-1 and VEGF were highly prominent in endometrial cancer, especially in the patients with low degree of differentiation, late stage and metastasis. They functioned synergistically in the onset and progression of this cancer.