Expression Levels Of Podoplanin Research Articles

Podoplanin mediates the renoprotective effect of berberine on diabetic kidney disease in mice.

Hyperglycemia-caused podocyte injury plays a crucial role in the progress of diabetic kidney disease. Podoplanin, one of the podocyte-associated molecules, is closely related to the integrity of the glomerular filtration barrier. A number of studies demonstrate that berberine could ameliorate renal dysfunction in diabetic mice with nephropathy, but the molecular mechanisms have not been fully elucidated. In this study, we explored the relationship between the renoprotective effect of berberine and podoplanin expression in streptozotocin (STZ)-induced diabetic mice as well as mouse podocytes (MPC5 cells) cultured in high glucose (HG, 30 mM) medium. We found that the expression levels of podoplanin were significantly decreased both in the renal glomerulus of STZ-induced diabetic mice and HG-cultured MPC5 cells. We also demonstrated that NF-κB signaling pathway was activated in MPC5 cells under HG condition, which downregulated the expression level of podoplanin, thus leading to increased podocyte apoptosis. Administration of berberine (100, 200 mg/kg every day, ig, for 8 weeks) significantly improved hyperglycemia and the renal function of STZ-induced diabetic mice and restored the expression level of podoplanin in renal glomerulus. In high glucose-cultured MPC5 cells, treatment with berberine (30–120 μM) dose-dependently decreased the apoptosis rate, increased the expression of podoplanin, and inhibited the activation of NF-κB signaling pathway. When podoplanin expression was silenced with shRNA, berberine treatment still inhibited the NF-κB signaling pathway, but its antiapoptotic effect on podocytes almost disappeared. Our results suggest that berberine inhibits the activation of NF-κB signaling pathway, thus increasing the podoplanin expression to exert renoprotective effects.

Therapeutic efficacy evaluation of radioimmunotherapy with 90 Y-labeled anti-podoplanin antibody NZ-12 for mesothelioma.

Podoplanin is a type I transmembrane sialomucin‐like glycoprotein that is highly expressed in malignant mesothelioma. The rat‐human chimeric antibody NZ‐12 has high affinity for human podoplanin and antibody‐dependent cellular cytotoxicity and is applicable for radioimmunotherapy (RIT) to enhance the antitumor effect. In the present study, we evaluated the in vivo and in vitro properties of radiolabeled NZ‐12 and the antitumor effect of RIT with 90Y‐labeled NZ‐12 in an NCI‐H226 (H226) malignant mesothelioma xenograft mouse model. 111In‐labeled NZ‐12 bound specifically to H226 cells with high affinity, and accumulation was high in H226 tumors but low in major organs. RIT with 90Y‐labeled NZ‐12 significantly suppressed tumor growth and prolonged survival without body weight loss and obvious adverse effects. Higher podoplanin expression levels were observed in human mesothelioma specimens, suggesting higher tumor accumulation of 90Y‐labeled NZ‐12 in patients compared with the H226 tumor xenografts. Our findings suggest that 90Y‐labeled NZ‐12 is a promising RIT agent as a new therapeutic option for malignant mesothelioma that warrants further clinical studies to evaluate the dosimetry and efficacy in patients.

Combination of isocitrate dehydrogenase 1 (IDH1) mutation and podoplanin expression in brain tumors identifies patients at high or low risk of venous thromboembolism

Essentials Risk stratification for venous thromboembolism (VTE) in patients with brain tumors is challenging.Patients with IDH1 wildtype and high podoplanin expression have a 6‐month VTE risk of 18.2%.Patients with IDH1 mutation and no podoplanin expression have a 6‐month VTE risk of 0%. IDH1 mutation and podoplanin overexpression in primary brain tumors appear to be exclusive. SummaryBackgroundVenous thromboembolism (VTE) is a frequent complication in primary brain tumor patients. Independent studies revealed that podoplanin expression in brain tumors is associated with increased VTE risk, whereas the isocitrate dehydrogenase 1 (IDH1) mutation is associated with very low VTE risk.ObjectivesTo investigate the interrelation between intratumoral podoplanin expression and IDH1 mutation, and their mutual impact on VTE development.Patients/MethodsIn a prospective cohort study, intratumoral IDH1 R132H mutation and podoplanin were determined in brain tumor specimens (mainly glioma) by immunohistochemistry. The primary endpoint of the study was symptomatic VTE during a 2‐year follow‐up.ResultsAll brain tumors that expressed podoplanin to a medium‐high extent showed also an IDH1 wild‐type status. A score based on IDH1 status and podoplanin expression levels allowed prediction of the risk of VTE. Patients with wild‐type IDH1 brain tumors and high podoplanin expression had a significantly increased VTE risk compared with those with mutant IDH1 tumors and no podoplanin expression (6‐month risk 18.2% vs. 0%).Conclusions IDH1 mutation and podoplanin overexpression seem to be exclusive. Although brain tumor patients with IDH1 mutation are at very low risk of VTE, the risk of VTE in patients with IDH1 wild‐type tumors is strongly linked to podoplanin expression levels.

Analysis of cancer-associated fibroblasts and the epithelial-mesenchymal transition in cutaneous basal cell carcinoma, squamous cell carcinoma, and malignant melanoma

Activated cancer-associated fibroblasts (CAFs) and fibroblasts that have undergone the epithelial-mesenchymal transition (EMT) in cancer stroma contribute to tumor progression and metastasis. However, no reports have investigated the CAF phenotype and its clinicopathological relevance in cutaneous malignant tumors, including basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and malignant melanoma (MM). Here, we investigated the CAF phenotype in cutaneous malignant tumors based on their histology and immunohistochemical expression of CAF-related markers, including adipocyte enhancer-binding protein 1 (AEBP1), podoplanin, platelet-derived growth factor receptor α (PDGFRα), PDGFRβ, fibroblast activating protein (FAP), CD10, S100A4, α-smooth muscle actin (α-SMA), and EMT-related markers (Zeb1, Slug, and Twist). In addition, we assessed the role of the CAF phenotype in cutaneous malignant cancers using hierarchical cluster analysis. Consequently, 3 subgroups were stratified based on the expression pattern of CAF- and EMT-related markers. Subgroup 1 was characterized by low expression of AEBP1, PDGFRα, PDGFRβ, FAP and Slug, whereas subgroup 2 was closely associated with high expression of PDGFRβ, S100A4 and Twist. In addition, high expression levels of podoplanin, PDGFRβ, CD10, S100A4, α-SMA, Zeb1, Slug and Twist were observed in subgroup 3. High expression of CD10 was commonly found in all 3 subgroups. These subgroups were correlated with histologic subtypes, that is, subgroup 1, MM; subgroup 2, BCC; and subgroup 3, SCC. We suggest that the expression pattern of CAF- and EMT-related proteins plays crucial roles in the progression of BCC, SCC, and MM.

Podoplanin Expression and Its Preclinical Application for Near-Infrared Imaging for Oral Squamous Cell Carcinoma

Podoplanin, which is a 38 kDa type I transmembrane glycoprotein, was initially identified as a platelet aggregation-inducing factor in cancer cells, and plays an important role in the formation of lymphatic vascular systems. Podoplanin is also expressed in many types of cancers such as lung cancer, cervical cancer, skin cancer, and esophageal cancer. Previous studies have reported that approximately 60%-70% of oral squamous cell carcinoma (OSCC) showed overexpression of podoplanin, suggesting a role in tumor progression and metastasis thorough various mechanisms. Moreover, previous studies have indicated that podoplanin overexpression in OSCC was associated with poor prognosis. However, application of podoplanin expression to diagnostic imaging for OSCC has not been reported. In the present study, we developed a sensitive near-infrared (NIR) fluorescence imaging method, which consists of an indocyanine green (ICG)-labeled anti-human podoplanin antibody as a probe and ICG imaging device, and examined its detection sensitivity and specificity using 4 types of OSCC xenografted tumors with different levels of podoplanin expression in mice.

The prognostic values of the expression of Vimentin, TP53, and Podoplanin in patients with cervical cancer

PurposeEpithelial–mesenchymal transition (EMT), TP53, and Podoplanin have been implicated in the tumorigenesis and metastasis of human cancers. Nevertheless, the clinical significance of these markers in cancer patients is still not clear. In this study, we sought to determine the prognostic values of Vimentin, TP53, and Podoplanin in patients with cervical cancer.MethodsQuantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analysis were performed to determine the messenger RNA and protein expression levels of Vimentin, TP53, and Podoplanin, respectively, in cervical squamous cell carcinoma and adjacent normal cervical tissues. Additionally, the expression levels of Podoplanin were also measured in 130 cervical cancer patients (FIGO stages Ib1–IIa2) using immunohistochemistry (IHC) staining.ResultsThe mRNA expression levels of Vimentin, TP53, and Podoplanin were considerably elevated in cervical cancer tissues, compared with those in the adjacent normal cervical tissues. Additionally, the protein expression levels of Vimentin were closely correlated with the age of onset (P = 0.007), lymph node metastasis (P = 0.007), lymphatic invasion (P = 0.024), disease recurrence (P < 0.001), and the clinical prognosis of patients with cervical cancer (P < 0.001). Our multivariate analysis also suggests that Vimentin is an independent marker for survival in cervical cancer patients. Furthermore, the expression levels of Vimentin are negatively correlated with the proliferation marker Ki67 expression.ConclusionsOur data show that Vimentin can serve as an independent prognostic marker for cervical cancer patients with primary surgery.Registration number ChiCTR-TRC-06000236 Registered 15 December 2006

Histopathological and immunohistochemical study in keratocystic odontogenic tumors: Predictive factors of recurrence.

The aim of the present study was to identify the most useful markers for predicting recurrence of keratocystic odontogenic tumors (KCOTs). A total of 65 tumor samples from 63 patients diagnosed with typical parakeratinized cysts and KCOTs between 1992 and 2014 were retrospectively studied. Clinical and histopathological data and treatment modality were reviewed. In addition, the expression profiles of Ki-67, cluster of differentiation (CD)34 and podoplanin were assessed using immunohistochemistry. The association between these factors and the rate of KCOT recurrence was evaluated. The presence of daughter cysts, epithelial islands and high Ki-67, CD34 and podoplanin expression levels were revealed to be associated with tumor recurrence. In particular, univariate analysis revealed that high CD34 expression levels were significantly associated with tumor recurrence (P=0.034), as was conservative surgical treatment (P=0.003). Multivariate analysis revealed that conservative treatment was the greatest independent risk factor for tumor recurrence (odds ratio=13.337; P=0.018). These results suggest that overexpression of CD34 may be a potent predictor of tumor recurrence and radical treatment of the teeth that are in contact with the tumors is recommended in order to prevent tumor recurrence.

Correlation between podoplanin expression and extracapsular spread in squamous cell carcinoma of the oral cavity using subjective immunoreactivity scores and semiquantitative image analysis.

The correlation between podoplanin expression and extracapsular spread in head and neck squamous cell carcinoma (HNSCC) has never been reported. The purpose of this study was to assess the predictive value of podoplanin expression for this parameter. Subjective immunoreactivity scores and semiquantitative image analysis of podoplanin expression were performed in 67 patients with primary oral squamous cell carcinoma and in their corresponding lymph nodes. Neck classification showed 34 cases (51%) of pN0 and 33 cases (49%) of pN+. Correlation between the levels of podoplanin expression and the histopathological data was established. In lymph nodes, a high level of podoplanin expression correlated with the presence of extracapsular spread by multivariate analysis (p = .03). A strong correlation between subjective and semiquantitative image analysis was observed (r = 0.77; p < .001). A high level of podoplanin expression in lymph node metastases of oral squamous cell carcinoma is independently associated with extracapsular spread. © 2016 Wiley Periodicals, Head Neck 39: 98-108, 2017.

Platelets Regulate the Migration of Keratinocytes via Podoplanin/CLEC-2 Signaling during Cutaneous Wound Healing in Mice

Podoplanin is an endogenous ligand for C-type lectin-like receptor 2 (CLEC-2), which is expressed on platelets. Recent evidence indicates that this specific marker of lymphatic endothelial cells is also expressed by keratinocytes at the edge of wounds. However, whether podoplanin or platelets play a role in keratinocyte activity during wound healing remains unknown. We evaluated the effect of podoplanin expression levels on keratinocyte motility using cultured primary normal human epidermal keratinocytes (NHEKs). Down-regulation of podoplanin in NHEKs via transfection with podoplanin siRNA inhibited their migration, indicating that podoplanin plays a mandatory role in this process. In addition, down-regulation of podoplanin was correlated with up-regulation of E-cadherin, suggesting that podoplanin-mediated stimulation of keratinocyte migration is associated with a loss of E-cadherin. Both the addition of platelets and treatment with CLEC-2 inhibited the migration of NHEKs. The down-regulation of RhoA activity and the up-regulation of E-cadherin in keratinocytes were also induced by CLEC-2. In conclusion, these results suggest that podoplanin/CLEC-2 signaling regulates keratinocyte migration via modulating E-cadherin expression through RhoA signaling. Altering the regulation of keratinocyte migration by podoplanin might be a novel therapeutic approach to improve wound healing.

Podoplanin is involved in the prognosis of head and neck squamous cell carcinoma through interaction with VEGF-C.

We investigated the clinical significance of podoplanin expression in relation to clinicopathological variables in head and neck squamous cell carcinoma (HNSCC), to determine its effectiveness as a marker for high-risk HNSCC patients. Upregulation of podoplanin in HNSCC tissues was examined using immunohistochemistry and clinicopathological analyses. Wound healing and invasion assays were performed using HNSCC cells that were transfected with podoplanin siRNA, podoplanin vector and cotransfection with both the podoplanin vector and VEGF-C siRNA. High podoplanin expression was significantly associated with ~3- and 5-fold increases in the presence of positive lymph node metastasis and poor histological grade, respectively (P<0.05). High levels of podoplanin expression were significantly associated with decreased overall and disease-specific survival rates (P<0.05). Furthermore, upregulation of podoplanin induced cell wound repair activity and invasiveness in the FaDu and SNU-1041 cells, respectively, while downregulation of podoplanin expression through VEGF-C silencing using co-transfection of both the podoplanin vector and VEGF-C siRNA suppressed cell wound healing and invasion abilities in the HNSCC cells. Our findings suggest that high podoplanin expression is associated with aggressive tumor behavior, poor prognosis and metastatic regulation through interaction with VEGF-C, suggesting that podoplanin may be used as a potential prognostic biomarker for HNSCC.

A microarray analysis of two distinct lymphatic endothelial cell populations.

We have recently identified lymphatic endothelial cells (LECs) to form two morphologically different populations, exhibiting significantly different surface protein expression levels of podoplanin, a major surface marker for this cell type. In vitro shockwave treatment (IVSWT) of LECs resulted in enrichment of the podoplaninhigh cell population and was accompanied by markedly increased cell proliferation, as well as 2D and 3D migration. Gene expression profiles of these distinct populations were established using Affymetrix microarray analyses. Here we provide additional details about our dataset (NCBI GEO accession number GSE62510) and describe how we analyzed the data to identify differently expressed genes in these two LEC populations.

Abstract 43: Podoplanin in head and neck squamous cell carcinoma: Prognostic value and clinicopathological implications

Abstract Background: Podoplanin is a mucin-type transmembrane glycoprotein that is important in lymphangiogenesis. We investigated the associations of podoplanin expression status with clinicopathological variables and the prognostic influence of podoplanin expression in head and neck squamous cell carcinoma (HNSCC), to determine its effectiveness as a marker of high-risk HNSCC subjects. Patients and Methods: We analyzed by immunohistochemistry podoplanin expression and its associations with the clinicopathological characteristics of 119 surgically treated HNSCC cases. Additionally, we investigated the effects of podoplanin expression on overall survival and disease-specific survival in univariate and multivariate analyses. Results: Of 119 HNSCC patients, high podoplanin expression was found in 61 cases (51.3%) and low expression in 58 (48.7%). High podoplanin expression was associated with lymph node metastasis, advanced AJCC stage, and poor histological grade (p &amp;lt; 0.05). In multivariate analysis, high podoplanin expression was significantly associated with circa three- and fivefold increases in the presence of positive lymph node metastasis and poor histological grade, respectively (p &amp;lt; 0.05). High levels of podoplanin expression were significantly associated with decreased overall survival and disease-specific survival (p &amp;lt; 0.05). Conclusions: Our findings suggest that high podoplanin expression is associated with aggressive tumor behavior and poor prognosis in HNSCC. Note: This abstract was not presented at the meeting. Citation Format: Bon Seok Koo, Kyu Lim. Podoplanin in head and neck squamous cell carcinoma: Prognostic value and clinicopathological implications. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 43. doi:10.1158/1538-7445.AM2014-43

Mo1726 Failure of Bilirubin-Mediated Immunosuppression Can Be Linked to Increased Efflux From Cells Driven by Heightened Activation of MDR1 Glycoprotein on T-Cells in Crohn's Disease

Background: Lymphocyte infiltration into the intestinal mucosa is an important pathogenic feature of inflammatory bowel diseases (IBD). In case of dermatitis, lymphatics play a role as drainage route of lymphocytes from skin and an inhibition of lymphangiogenesis keeps lymphocytes remaining in the local area leading to exacerbate inflammation. However, the role of lymphatics in enterocolitis is not well understood. In this study, we examined changes in lymphatic densities and expression of lymphangiogenic factors in patients with IBD and in animal model of colitis, and investigated a role of lymphangiogenic using inhibitor of VEGF (vascular endothelial growth factor)-R3. Method: Colonic biopsies were obtained from 40 patients with ulcerative colitis (UC), 17 patients with Crohn's disease (CD), and controls. Messenger RNA expressions of lymphangiogenic factors, VEGFC & D, VEGFR3, podoplanin, Prox-1, and LYVE1 were determined using real time RT-PCR. Expression of CD34 and LYVE1 was studied immunohistochemically. In dextran sulfate sodium (DSS)-induced mice colitis, a VEGF-R3 kinase inhibitor (10mg/kg) was administered every day and the effects of lymphangiogenetic inhibition on activity of colitis and lymphatic density were determined in the colonic mucosa. Result: In the colonic mucosa of patients with UC and CD, the expressions of VEGFC, VEGFR3, podoplanin, and LYVE1 were significantly increased than the mucosa of control patients. The expression levels of podoplanin and LYVE1 were well correlated to endoscopic Matt's score in UC patients. By immunohistochemistry, the lymphatic densities in the colonic mucosa of IBD patients also increased compared to control patients. However, interestingly those densities were not significantly increased in the severely inflamed mucosa of IBD patients compared with those in the quiescent mucosa, suggesting that lymphangiogenesis and lymphatic drainage are not well organized in the severely inflamed mucosa. In murine colitis model, VEGF-R3 inhibition group showed significant aggravation of colitis such as shortening of colonic length and increase in the lymphocyte infiltration in the submucosa compared with DSS-treatment alone. Lymphatic densities decreased in the submucosa of VEGF-R3 inhibition group. Conclusions: The results of our study revealed that lymphangiogenic factors and lymphatic density are increased in both UC and CD patients. However, the density of lymphatic did not increase as inflammation advanced. Aggravation of colitis by lymphangiogenic receptor inhibition suggests that lymphatic networks may play some protective roles as exit of immune cells from intestinal mucosa, and that some mechanisms which block lympangiogenesis play aggravating role in severe IBD patients. In the severely inflamed conditions lymphatic drainage through lymphangiogenesis is not well functioning in IBD.

Mo1727 Impaired Expression of the Aryl Hydrocarbon Receptor and CD39 Is Associated With Heightened Pathogenicity of T Helper Type 17 Cells in Crohn's Disease

Background: Lymphocyte infiltration into the intestinal mucosa is an important pathogenic feature of inflammatory bowel diseases (IBD). In case of dermatitis, lymphatics play a role as drainage route of lymphocytes from skin and an inhibition of lymphangiogenesis keeps lymphocytes remaining in the local area leading to exacerbate inflammation. However, the role of lymphatics in enterocolitis is not well understood. In this study, we examined changes in lymphatic densities and expression of lymphangiogenic factors in patients with IBD and in animal model of colitis, and investigated a role of lymphangiogenic using inhibitor of VEGF (vascular endothelial growth factor)-R3. Method: Colonic biopsies were obtained from 40 patients with ulcerative colitis (UC), 17 patients with Crohn's disease (CD), and controls. Messenger RNA expressions of lymphangiogenic factors, VEGFC & D, VEGFR3, podoplanin, Prox-1, and LYVE1 were determined using real time RT-PCR. Expression of CD34 and LYVE1 was studied immunohistochemically. In dextran sulfate sodium (DSS)-induced mice colitis, a VEGF-R3 kinase inhibitor (10mg/kg) was administered every day and the effects of lymphangiogenetic inhibition on activity of colitis and lymphatic density were determined in the colonic mucosa. Result: In the colonic mucosa of patients with UC and CD, the expressions of VEGFC, VEGFR3, podoplanin, and LYVE1 were significantly increased than the mucosa of control patients. The expression levels of podoplanin and LYVE1 were well correlated to endoscopic Matt's score in UC patients. By immunohistochemistry, the lymphatic densities in the colonic mucosa of IBD patients also increased compared to control patients. However, interestingly those densities were not significantly increased in the severely inflamed mucosa of IBD patients compared with those in the quiescent mucosa, suggesting that lymphangiogenesis and lymphatic drainage are not well organized in the severely inflamed mucosa. In murine colitis model, VEGF-R3 inhibition group showed significant aggravation of colitis such as shortening of colonic length and increase in the lymphocyte infiltration in the submucosa compared with DSS-treatment alone. Lymphatic densities decreased in the submucosa of VEGF-R3 inhibition group. Conclusions: The results of our study revealed that lymphangiogenic factors and lymphatic density are increased in both UC and CD patients. However, the density of lymphatic did not increase as inflammation advanced. Aggravation of colitis by lymphangiogenic receptor inhibition suggests that lymphatic networks may play some protective roles as exit of immune cells from intestinal mucosa, and that some mechanisms which block lympangiogenesis play aggravating role in severe IBD patients. In the severely inflamed conditions lymphatic drainage through lymphangiogenesis is not well functioning in IBD.

Mo1725 Possible Protective Role of Lymphangiogenesis in the Inflamed Colonic Mucosa of Inflammatory Bowel Diseases

Background: Lymphocyte infiltration into the intestinal mucosa is an important pathogenic feature of inflammatory bowel diseases (IBD). In case of dermatitis, lymphatics play a role as drainage route of lymphocytes from skin and an inhibition of lymphangiogenesis keeps lymphocytes remaining in the local area leading to exacerbate inflammation. However, the role of lymphatics in enterocolitis is not well understood. In this study, we examined changes in lymphatic densities and expression of lymphangiogenic factors in patients with IBD and in animal model of colitis, and investigated a role of lymphangiogenic using inhibitor of VEGF (vascular endothelial growth factor)-R3. Method: Colonic biopsies were obtained from 40 patients with ulcerative colitis (UC), 17 patients with Crohn's disease (CD), and controls. Messenger RNA expressions of lymphangiogenic factors, VEGFC & D, VEGFR3, podoplanin, Prox-1, and LYVE1 were determined using real time RT-PCR. Expression of CD34 and LYVE1 was studied immunohistochemically. In dextran sulfate sodium (DSS)-induced mice colitis, a VEGF-R3 kinase inhibitor (10mg/kg) was administered every day and the effects of lymphangiogenetic inhibition on activity of colitis and lymphatic density were determined in the colonic mucosa. Result: In the colonic mucosa of patients with UC and CD, the expressions of VEGFC, VEGFR3, podoplanin, and LYVE1 were significantly increased than the mucosa of control patients. The expression levels of podoplanin and LYVE1 were well correlated to endoscopic Matt's score in UC patients. By immunohistochemistry, the lymphatic densities in the colonic mucosa of IBD patients also increased compared to control patients. However, interestingly those densities were not significantly increased in the severely inflamed mucosa of IBD patients compared with those in the quiescent mucosa, suggesting that lymphangiogenesis and lymphatic drainage are not well organized in the severely inflamed mucosa. In murine colitis model, VEGF-R3 inhibition group showed significant aggravation of colitis such as shortening of colonic length and increase in the lymphocyte infiltration in the submucosa compared with DSS-treatment alone. Lymphatic densities decreased in the submucosa of VEGF-R3 inhibition group. Conclusions: The results of our study revealed that lymphangiogenic factors and lymphatic density are increased in both UC and CD patients. However, the density of lymphatic did not increase as inflammation advanced. Aggravation of colitis by lymphangiogenic receptor inhibition suggests that lymphatic networks may play some protective roles as exit of immune cells from intestinal mucosa, and that some mechanisms which block lympangiogenesis play aggravating role in severe IBD patients. In the severely inflamed conditions lymphatic drainage through lymphangiogenesis is not well functioning in IBD.

Ebp1 activates podoplanin expression and contributes to oral tumorigenesis

Podoplanin is highly expressed in human cancers. However, mechanisms regulating podoplanin expression remain elusive. Here we show that podoplanin promotes tumorigenesis of oral squamous cell carcinoma (OSCC) and precancerous cells both in vitro and in vivo, and the ErbB3-binding protein-1 (Ebp1) can be activated in oral tumorigenesis and can serve as a transcriptional activator to drive podoplanin expression in the malignant progression. Most of the OSCC cell lines have no detectable podoplanin protein in low-density cultures. However, the protein becomes detectable in high-density cultures and is required for in-vivo tumor formation of OSCC and oral premalignancies. In a high-density culture condition, podoplanin expression can be triggered at both mRNA and protein levels. In this condition, we showed that Ebp1 is upregulated, translocated from the cytoplasm to the nucleus and binds to the podoplanin promoter to result in a dramatic increase of podoplanin mRNA and protein. Ebp1 downregulation significantly reduced podoplanin expression levels in OSCC cells with a decreased anchorage-dependent growth, invasion and wound healing. Conversely, Ebp1 overexpression enhanced these malignant features through podoplanin upregulation both in vitro and in vivo. In 81 patients with oral premalignant lesions, we found that Ebp1 expression is strongly related to OSCC development. We conclude that Ebp1 has a key role in the upregulation of podoplanin and may contribute to oral tumorigenesis.

Podoplanin expression in cutaneous head and neck squamous cell carcinoma—prognostic value and clinicopathologic implications

Although most patients are cured by local treatment from cutaneous head and neck squamous cell carcinoma (cHNSCC), a significant number of patients develops metastases to the regional lymph nodes. Recent studies suggest an influence of podoplanin expression on regional lymph node metastases in other head and neck squamous cell carcinoma. The aim of our study was to assess the impact of podoplanin expression on regional lymph node metastasis, locoregional recurrence, and prognosis. In this retrospective study, podoplanin expression was examined immunohistochemically in 63 treatment-naive patients with cHNSCC. We analyzed associations of podoplanin expression and clinicopathologic variables. Furthermore, we investigated the effects on overall survival (OS) and locoregional control in univariate and multivariate analysis. In 40 patients (63.5%), podoplanin was expressed in the tumor cells. The χ(2) -test revealed that podoplanin expression was associated with the number of tumorous lymph nodes (P < 0.001). The OS was significantly influenced by podoplanin expression (P < 0.001). None of the patients with high levels of podoplanin expression survived, whereas the 5-year OS for patients with podoplanin-negative tumors was 91.3%. We concluded that podoplanin is frequently expressed in cHNSCC and might serve as predictor for regional lymph node metastases, locoregional recurrence, and clinical outcome.

Role of podoplanin expression in esophageal squamous cell carcinoma: A retrospective study

Lymphatic metastasis is the predominant cause of the low overall survival of patients with esophageal squamous cell carcinoma (ESCC), as there are no faithful methods available predicting early metastasis. Recent studies suggest an effect of podoplanin expression on metastatic spreading to lymph nodes. The purpose of this study was to investigate the influence of podoplanin expression on lymphatic metastasis and tumor cells, and to find the relationship between podoplanin expression and prognosis of patients with ESCC. We evaluated the level of podoplanin expression on tumor cells and the lymphatic vessel density change of tumor mass compared with normal tissue from the same patient through D2-40 immunohistochemistry staining, and analyzed associations between these two variables and various clinicopathologic parameters individually or conjunctively. There was an association between podoplanin expression and the frequency of lymph node metastases. In 45 patients (80%), podoplanin was expressed on the tumor cells. Twenty-one patients (37.5%) showed high levels of expression. The 5-year disease-free survival rate (5%) for patients with high levels of podoplanin expression was significantly lower (P < 0.001) than for patients with low and moderate expression of podoplanin (54% and 27%, respectively). We concluded that podoplanin is expressed frequently in ESCC, and that the expression of podoplanin on cancer cells, lymphatics, or both is correlated with lymphatic metastasis and clinical outcome.

Podoplanin and SOX2 expression in esophageal squamous cell carcinoma after neoadjuvant chemo-radiotherapy

Neoadjuvant chemo-radiotherapy (CRT) followed by surgery are the standard approaches for locally advanced esophageal cancer. However, the overall cure rate is very low. The aim of this preliminary study was to evaluate the expression of podoplanin and SOX2 known as stemness markers for esophageal squamous cell carcinoma (ESCC) and their association with clinical outcome. We obtained a total of 20 specimens from patients with ESCC who underwent neoadjuvant CRT (30-40 Gy; 5-fluorouracil plus cisplatin) followed by surgery. Podoplanin and SOX2 expression was evaluated using immunohistochemistry and the association of their expressions with clinicopathological variables was investigated. Podoplanin and SOX2 staining was detected not only in residual cancer cells, but also in the basal layer of adjacent normal mucosa after neoadjuvant CRT. High expression of podoplanin was correlated with lymph node metastasis, advanced postoperative stage and vascular invasion (P<0.05), while, high expression of SOX2 was correlated with lymphatic, vascular invasion, poor differentiated tumor and incomplete resection (P<0.05). High expression of podoplanin was significantly associated with poor overall survival (P<0.05). In conclusion, the expression levels of podoplanin and SOX2 expression may be useful prognostic markers for ESCC treated with neoadjuvant CRT.

Tumor Lymphangiogenesis and Metastasis to Lymph Nodes Induced by Cancer Cell Expression of Podoplanin

The membrane glycoprotein podoplanin is expressed by several types of human cancers and might be associated with their malignant progression. Its exact biological function and molecular targets are unclear, however. Here, we assessed the relevance of tumor cell expression of podoplanin in cancer metastasis to lymph nodes, using a human MCF7 breast carcinoma xenograft model. We found that podoplanin expression promoted tumor cell motility in vitro and, unexpectedly, increased tumor lymphangiogenesis and metastasis to regional lymph nodes in vivo, without promoting primary tumor growth. Importantly, high cancer cell expression levels of podoplanin correlated with lymph node metastasis and reduced survival times in a large cohort of 252 oral squamous cell carcinoma patients. Based on comparative transcriptional profiling of tumor xenografts, we identified endothelin-1, villin-1, and tenascin-C as potential mediators of podoplanin-induced tumor lymphangiogenesis and metastasis. These unexpected findings identify a novel mechanism of tumor lymphangiogenesis and metastasis induced by cancer cell expression of podoplanin, suggesting that reagents designed to interfere with podoplanin function might be developed as therapeutics for patients with advanced cancer.