Detection of D2-40 monoclonal antibody-labeled lymphatic vessel invasion in esophageal squamous cell carcinoma and its clinicopathologic significance

Podoplanin: A potential therapeutic target for thrombotic diseases

As a specific lymphatic marker and a key ligand of C-type lectin-like receptor 2 (CLEC-2), podoplanin (Pdpn) is involved in various physiological and pathological processes such as growth and development, respiration, blood coagulation, lymphangiogenesis, angiogenesis, and inflammation. Thrombotic diseases constitute a major cause of disability and mortality in adults, in which thrombosis and inflammation play a crucial role. Recently, increasing evidence demonstrates the distribution and function of this glycoprotein in thrombotic diseases such as atherosclerosis, ischemic stroke, venous thrombosis, ischemic-reperfusion injury (IRI) of kidney and liver, and myocardial infarction. Evidence showed that after ischemia, Pdpn can be acquired over time by a heterogeneous cell population, which may not express Pdpn in normal conditions. In this review, the research progresses in understanding the roles and mechanisms of podoplanin in thromobotic diseases are summarized. The challenges of podoplanin-targeted approaches for disease prognosis and preventions are also discussed.

Immunohistochemical Evaluation of Histological Change in a Chinese Milroy Disease Family With Venous and Skin Abnormities

Background: Milroy disease (MD) is rare and autosomal dominant resulting from mutations of the vascular endothelial growth factor receptor-3 (VEGFR-3 or FLT4), which leads to dysgenesis of the lymphatic system.

Methods: Here we report a Chinese MD family with 2 affected members of two generations. We identified the mutation of c.3075G>A in one allele of FLT4 in Chinese population firstly. The father and child presented lymphedema under knees both. Unfortunately, the child was premature delivered for a car accident of the mother and then died of asphyxia. Then we gathered the tissue of the lower-limb from the child with permission from the parents and ethic committee. We stained the tissue with lymphatic marker D2-40 and hematoxylin-eosin to explore the histological changes. Afterwards, we compared the results with a normal child who unfortunately died of premature delivery also.

Results: It is firstly identified the mutation of FLT4: c.3075G>A in Chinese population, and the mutation Inherited in the lineage. The histological evaluation indicated: (1) The number of lymphatic vessels decreased; (2) The morphology and structure of lymphatic vessels was abnormal. And what is added to our knowledge: (1) Capillary hyperemia and phlebectasia is severe; (2) Vascular malformations; (3) The number of vascular endothelial cells and vascular smooth muscle cells decreased; (4) Large sheets of epidermis desquamated; (5) The numbers of cutaneous appendages reduced in MD.

Conclusions: Based on the new findings, we assume that mutation of FLT4 not only affect the lymphogenesis, but also the angiogenesis, and epidermis structure.

Plasma soluble podoplanin is a novel marker for the diagnosis of tumor occurrence and metastasis

Podoplanin (PDPN) is expressed on many tumors and is involved in tumor metastasis. The objective of the present study was to develop an ELISA for determining soluble PDPN (sPDPN) levels as a potential novel tumor marker in plasma of patients with cancers for detection of tumor occurrence and metastasis. Mouse monoclonal antibodies (mAb) against human PDPN were developed and characterized. Two anti-PDPN mAb, SZ-163 and SZ-168, were used in a sandwich ELISA to detect plasma sPDPN in patients with cancers and in normal individuals. The levels of sPDPN were detected in patients with adenocarcinoma (87 cases, 31.09 ± 5.48 ng/ml), squamous cell carcinoma (86 cases, 6.91 ± 0.59 ng/ml), lung cancer (45 cases, 26.10 ± 7.62 ng/ml), gastric cancer (38 cases, 23.71 ± 6.90 ng/ml) and rectal cancer (27 cases, 32.98 ± 9.88 ng/ml), which were significantly higher than those in normal individuals (99 cases, 1.31 ± 0.13 ng/ml) (P < .0001). Moreover, the sPDPN levels in patients with metastatic cancers were higher (192 cases, 30.35 ± 3.63 ng/ml) than those in non-metastatic cancer patients (92 cases, 6.28 ± 0.77 ng/ml) (P < .0001). The post-treatment sPDPN levels of cancer patients (n = 156) (4.47 ± 0.35 ng/ml) were significantly lower compared with those seen pre-treatment (n = 128) (43.74 ± 4.97 ng/ml) (P < .0001). These results showed that an ELISA method was successfully established for quantitation of plasma sPDPN and plasma sPDPN levels correlate significantly with tumor occurrence and metastasis.

Cancer-associated fibroblasts are associated with poor prognosis in esophageal squamous cell carcinoma after surgery

OBJECTIVE

Cancer-associated fibroblasts (CAFs; α-SMA positivity), as a representative of the tumor microenvironment, play an important role in influencing the proliferation, invasion and metastasis of cancer cells. The objective is to investigate the prognostic value of CAFs density in esophageal squamous cell carcinoma (ESCC) after surgery.

METHOD

A total of 95 patients who underwent esophagectomy for ESCC in 2007 were included in this study. These specimens were immunostained with α-smooth muscle actin (α-SMA) antibodies to quantify CAFs. Antibodies D2-40 and CD34 were used to evaluate the lymphatic vessel density (LVD) and microvessel density (MVD) of the lesions. The Cox proportional hazards model was used to determine the hazard ratio of CAFs density on 3-year overall survival and 3-year disease-free survival. The correlation between CAFs density and lymphatic vessel density (LVD) or microvessel density (MVD) were analyzed.

RESULTS

3-year overall survival rate in the CAF-poor group (63%) was significantly better than those in the CAF-rich group (42%) (P < 0.01). In the Cox univariate and multivariate analysis of 3-year overall survival, the hazard ratio (HR) of CAFs density was 1.870 (95% CI 1.033-3.385; P = 0.039) and 2.196 (95% CI 1.150-4.193; P = 0.017), respectively. CAFs density was proved to be an independent prognostic factor for 3-year overall survival. CAFs density correlated significantly with increased LVD and MVD in ESCC.

CONCLUSION

CAFs density may be a marker for predicting prognosis and guiding therapeutic management of ESCC.

Clinicopathology significance of podoplanin immunoreactivity in esophageal squamous cell carcinoma

BACKGROUD AND AIM

Podoplanin (D2-40) is a specific marker for lymphatic endothelium. The vast majority of previous studies on podoplanin immunostaining in esophageal squamous cell carcinoma (ESCC) focused on identifying lymphatic vessel invasion (LVI) and counting lymphatic vessel density (LVD) and had contradictory results. Recent studies show podoplanin expression on cancer cells or tumor stroma in several cancers, which have specific significance; but the status in ESCC remains unclear. Therefore, the aim of this study was to further study and summarize the clinicopathological significance of podoplanin immunoreactivity in ESCC.

MATERIALS AND METHODS

We examined podoplanin expression in tissue specimens from 107 patients with ESCC by immunohistochemistry. Podoplanin positive lymphatic vessels in intratumoral and peritumoral tissues and podoplanin positive expression in cancer cells and tumor stroma were analyzed, and correlated with clinicopathologic parameters and three-year overall and free-disease survival.

RESULTS

34 (31.8%) and 28 (26.2%) of 107 specimens had podoplanin positive expression in cancer cells and tumor stroma, respectively. Logistic regression analysis showed high intratumoral lymphatic vessel density (I-LVD) and podoplanin positivity in cancer cells were increased risks of lymph node metastasis (LNM) (OR=2.45, P=0.03; OR=0.35, P=0.01, respectively). Survival analysis showed that I-LVD was a significant factor related to poor three-year overall and free-disease survival (P=0.04, P=0.03, respectively).

CONCLUSIONS

Previous data and our results show that podoplanin seems to be a useful marker to predict LNM, recurrence, and worse prognosis in ESCC; in particular, LVI, high I-LVD, and podoplanin positivity in cancer cells are associated with LNM, recurrence and overall survival.