Lymphagenesis and cancer metastasis

Intratumoral lymphatic vessel density as a predictor of progression-free and overall survival in locally advanced laryngeal/hypopharyngeal cancer

BACKGROUND

Lymphatic vessel density (LVD) has been shown to be an important predictor of survival in head and neck cancers. We report the predictive value of LVD for progression-free survival (PFS) and overall survival (OS) in laryngeal/hypopharyngeal cancer.

METHODS

Fifty-five untreated patients with T3/T4 laryngeal and T4 hypopharyngeal cancer underwent laryngectomy between 1999 and 2010. Surgical specimens were immunostained with D2-40, a specific lymphatic marker. LVDs were determined in tumor vessel "hot spots." Recursive partitioning analysis identified LVD thresholds for both peritumoral (LVDpt) and intratumoral (LVDit) vessels for association with PFS and OS.

RESULTS

Patients with mean LVDit of <11 vessels/mm(2) had 2-year PFS and OS rates of 58% and 65%, respectively, compared to 13% and 13% for those with LVDit ≥11 vessels/mm(2) (p = .06 and .04, respectively).

CONCLUSION

Intratumoral lymphatic vessel density is predictive of PFS and OS in locally advanced laryngeal/hypopharyngeal cancer. © 2015 Wiley Periodicals, Inc. Head Neck 38: E417-E420, 2016.

Prognostic value of lymphangiogenesis in supraglottic laryngeal carcinoma

Background:

Metastasis to regional lymph nodes via lymphatic microvessels plays a key role in cancer progression, and is an important prognostic factor in many cancers. Recent evidence suggests that tumour lymphangiogenesis promotes lymphatic metastasis.

Aims:

To investigate whether tumour lymphatic microvessel density correlates with clinicopathological factors and serves as a prognostic indicator of supraglottic laryngeal carcinoma progression.

Methods:

The lymphatics of 84 supraglottic laryngeal carcinoma cases were investigated by immunohistochemical staining for podoplanin (also termed D2-40). The relationships between (intra- and peritumoural) lymphatic microvessel density, clinicopathological parameters and clinical prognosis were analysed.

Results:

There was a significant relationship between high intratumoural lymphatic microvessel density and aggressive tumour node stage (p < 0.0001), distant metastasis (p = 0.037) and poor prognosis (p = 0.011), and between high peritumoural lymphatic microvessel density and node stage (p = 0.004) and poor prognosis (p = 0.029). Patients with high lymphatic microvessel density also had significantly worse disease-free survival (p = 0.003) and overall survival (p = 0.005). Intratumoural lymphatic microvessel density was found to be an independent prognostic factor for overall survival (p = 0.008) and disease-free survival (p = 0.005) (multivariate analysis).

Conclusion:

Lymphatic microvessel density (detected by podoplanin immunohistochemistry), especially intratumoural density, may be an independent predictor of lymphatic tumour spread and survival in supraglottic laryngeal carcinoma patients, and may be useful to guide decisions regarding additional surgery.

Generation and characterization of a mouse lymphatic endothelial cell line

Lymphatic vessels, by channeling fluid and leukocytes from the periphery into lymph nodes, play a central role in the development of the immune response. Despite their importance in homeostasis and disease, the difficulties in enriching and culturing lymphatic endothelial cells limit studies of their biology. Here, we report the isolation, stabilization, and characterization of a mouse lymphatic endothelial cell line (MELC) and the generated clones thereof. Cells were isolated from benign lymphangiomas induced by intraperitoneal injections of incomplete Freund's adjuvant. The MELC line expressed molecules typical of lymphatic endothelium, including VEGFR3/Flt-4, podoplanin, Prox-1, and D6, but not LYVE-1. It also expressed CD34, ICAM-1, VCAM, and JAM-A, but not CD31, VE-cadherin, E-selectin, or CX3CL1/fractalkine (both TNFalpha-induced), at variance with vascular endothelial cells tested in parallel. The inflammatory cytokines TNFalpha and IL-4 regulated production of selected adhesion molecules (VCAM), cytokines (IL-6), and chemokines (CCL2/JE). Whole genome transcriptional profiling identified a set of 150 known genes differentially expressed in MELC versus vascular endothelial cells. Thus, the MELC line may represent an invaluable source of lymphatic endothelium.

Lymphatic vessel density and lymph node metastasis in prostate cancer

BACKGROUND

Few data are available examining the significance of prostatic lymphatic vessel density (LVD) to lymph node metastasis in patients with prostate cancer. The purpose of this study was to determine the distribution of lymphatic vessels in non-carcinomatous prostate tissue, and investigate the relationship between LVD and lymph node status in prostate cancer.

METHODS

LVD, identified by D2-40 immunostaining, was evaluated in non-carcinomatous prostates (n = 7) and prostate cancer (n = 37). The staining pattern of D2-40 was compared with that of another lymphatic vessel marker, vascular endothelial growth factor (VEGF) receptor-3, and a blood vessel endothelial marker, CD34, in adjacent sections.

RESULTS

The D2-40 antigen, podoplanin, was expressed exclusively in lymphatic vessels within tumor and normal tissue in all specimens. There was no overlap between cell staining for D2-40 and CD34. Peritumoral LVD and peritumoral lymphatic invasion were significantly associated with lymph node metastasis. VEGF receptor-3 was expressed in a subset of D2-40+ lymphatic vessels.

CONCLUSIONS

We have demonstrated that peritumoral lymphatic vessels are likely to serve as major conduits for nodal metastasis in prostate cancer using D2-40 to decorate lymphatic endothelium marker podoplanin. Lack of coexpression of podoplanin and VEGF receptor-3 in some lymphatic vessels suggests the heterogeneity of lymphatic endothelial cells in prostate tissue.

Expression of vascular endothelial growth factor receptor 3 in blood and lymphatic vessels of lung adenocarcinoma

Vascular endothelial growth factor receptor 3 (VEGFR-3) has been proposed as a marker for lymphatic endothelial cells. This study investigated the expression of VEGFR-3 in the tumour vessels of lung adenocarcinoma and evaluated whether VEGFR-3 staining was useful for identifying lymphatic vessels within the tumour stroma. It also explored whether active growth of lymphatic vessels occurred in lung adenocarcinoma. Formalin-fixed, paraffin-embedded specimens obtained from 60 cases of lung adenocarcinoma, including five cases of pure bronchiolo-alveolar carcinoma (BAC) without stromal, vascular, and pleural invasion, were examined. No VEGFR-3-positive vessels were observed in pure BAC, but varying numbers of VEGFR-3-positive vessels were found in 39 of 55 (70.9%) invasive adenocarcinomas. A comparison of serial sections stained for VEGFR-3, CD31, and laminin-1 showed that most of the VEGFR-3-positive vessels appeared to be blood vessels (CD31-positive, laminin-1-positive), but some had the characteristics of lymphatic vessels (variable staining for CD31, little or no staining for laminin-1). VEGFR-3 staining highlighted lymphatic invasion by cancer cells; this invasion could not be detected by CD31 or haematoxylin and eosin (H&E) staining. Active growth of lymphatic vessels (as indicated by nuclear Ki-67 labelling of the endothelium) was observed in five tumours, four of which showed a high level of lymphatic invasion by cancer cells. It was concluded that VEGFR-3 immunostaining did not discriminate clearly between vascular and lymphatic endothelial cells, since expression of VEGFR-3 can be up-regulated in tumour blood vessels. However, VEGFR-3 staining combined with laminin-1 and CD31 staining would be useful for identifying lymphatic vessels and their invasion by tumour cells in a more objective way. Finally, proliferation of lymphatic endothelial cells may occur in association with lymphatic invasion by cancer cells.

Lymphatic microvessel density as a novel prognostic factor in early-stage invasive cervical cancer

Few data on the influence of lymphatic microvessel density (MVD) on survival in cancer are available since until recently there was no reliable immunohistological marker for lymphatic endothelium. Using an antibody staining podoplanin, a novel marker for lymphatic endothelium, lymphatic MVD in tissue samples of 85 patients with cervical cancer classification pT1b treated by radical hysterectomy was investigated. Survival was determined using univariate and multivariate analyses. Lymphatic MVD was also compared to MVD assessed by immunostaining against factor VIII-related antigen, which is considered a marker for blood vessels. Patients with >5 lymphatic microvessels/0.25 mm(2) field had significantly better overall survival (mean 91.8 months) than those with < or =5 lymphatic microvessels/field in univariate analysis (mean 113 months) (p = 0.0105, log-rank test). In multivariate analysis, lymphatic node involvement (p =0.0183), vessel infiltration (p =0.0158) and lymphatic MVD (p =0.0269) remained independent prognostic factors. No correlation between lymphatic MVD and various clinical and histopathological parameters was observed. Correlation between lymphatic MVD and MVD assessed by immunostaining against factor VIII was only weak (p = 0.004, r = 0.312, Spearman's coefficient of correlation). Our results suggest that increased lymphatic MVD is associated with favorable prognosis in early-stage cervical cancer.

Prognosis of breast-carcinoma lymphagenesis evaluated by immunohistochemical investigation of vascular-endothelial-growth-factor receptor 3

Very few studies have yet addressed the question of the existence and role of lymphagenesis in tumor growth; it is generally overshadowed by the greater emphasis placed on the blood vascular system. Monoclonal antibodies against vascular endothelial-growth-factor receptor 3 (VEGFR3) have been shown to provide a specific antigenic marker for lymphatic endothelium. By comparison with the microvascular count (MVC), we investigated the prognostic value of the microlymphatic count (MLC) in a series of 60 cases of 2-cm-diameter breast carcinomas. The mean value of MVC was 72.5 and of MLC, 40.5. There was no quantitative correlation between these 2 parameters. The MVC but not the MLC had a prognostic value in overall survival. Neither the MLC nor the MVC had any correlation with axillary-lymph-node invasion.