Lymphangiogenesis as a prerequisite in the pathogenesis of lung fibrosis

Despite increasing knowledge on the cellular and molecular mechanisms involved in pulmonary fibrosis, its therapeutic options are still limited. The study of lymphangiogenesis has contributed to a better understanding of tumor growth and metastasis, with a major impact upon changes in therapeutic strategies and this was followed by the research of lymphatic vessels in other pathological conditions. Some data support the possible role of lymphangiogenesis in the pathogenesis of lung fibrosis. However, at the time of diagnosis for each patient with a fibrotic interstitial lung disease, it is necessary to predict the prognosis and to choose for individual targeted-therapy. Our aim was the characterization of lymphangiogenesis as a useful tool to stratify patients with lung fibrosis. We evaluated the presence, morphology and density of D2-40-positive lymphatic vessels and co-localization of D2-40/Ki67 in pulmonary fibrosis with different degrees of severity and without a specific etiology. Lymphatic vessel density did not correlate with severity grade and ranged between 4.66 to 38.33 vessels/×40 field, with the highest value in degree III of fibrosis. An intense proliferative activity of lymphatic endothelial cells was found in 24% (6 out of 25) of cases. The morphology of lymphatics and the presence of splitting combined with the proliferative activity of endothelial cell pillars suggested two different mechanisms in the formation new lymphatic vessels. Our results support the hypothesis that the activity and ongoing evolution of fibrosis can be predicted through the characterization of lymphangiogenesis but its presence or absence cannot predict the severity of fibrosis.

Dual role of podoplanin in oral cancer development

Podoplanin plays a crucial role for normal and pathological tissue development. Known as a lymphatic endothelial marker, podoplanin has been found to be overexpressed in tumor cells of various cancers with a certified involvement in tumor progression, invasion and metastasis. Oral cancer includes a heterogeneous group of malignancies with unpredictable behaviour and sometimes poor prognosis. Based on these facts, development of new molecular markers with a more reliable impact on therapy and prognosis is required. The present study was designed to characterize podoplanin expression in tumor cells of lip, oral cavity, tongue and pharynx squamous cell carcinomas, together with lymphatic vessels distribution, morphology, density and their impact on tumor progression. Evaluation of podoplanin by D2-40 immunohistochemistry assessement on 56 cases of oral cancers, revealed two different expression patterns in tumor cells depending on their location. Peri-tumor and intra-tumor lymphatic vessels density, morphology and distribution were correlated with lymph node status but not with tumor stage. The highest number of lymphatic vessels was observed in grade 3 squamous cell carcinomas. Dual expression of podoplanin in tumor cells and lymphatics with particular patterns correlated with histopathology and lymph node status in oral cancer, representing the molecular basis for testing podoplanin as a potential target for anti D2-40 antibody based therapy.

Unusual bilateral cervical metastases as first clinical evidence of lung cancer

We report on an unusual case of laterocervical bilateral metastatatic masses with unknown clinical, radiological or computer tomographicic detected primary site of origin. Cancer of an unknown primary site is a clinical syndrome, accounting for 2%-5% of patients with cancer. The peculiarities of our case are its evolution as fast-growing bilateral tumor masses with involvement of other neck structures and its unexpected origin from the lung, certified by complementary immunohistochemical tests following surgery, in the absence of any other clinical signs or any detectable lung tumor mass by radiological or computer tomographic tests.

Intranodal hemorrhagic spindle cell tumor with amianthoid fibers - report of a case with emphasis to mast cell reaction and d2-40 expression

AIM

Intranodal palisaded myofibroblastoma (IPM) is a rare benign mesenchymal tumor restricted to the lymph nodes. Here, we report the case of a 44-year-old male patient with an IPM confined to the left laterocervical area.

CASE REPORT

After an accurate microscopic evaluation of morphological and histochemical stains, immunohistochemistry was performed for vimentin, smooth muscle actin vascular markers, S100 protein, D2-40, Ki67, lymphoid and melanoma markers, keratin and desmin on sections obtained from a paraffin-embedded surgical biopsy.

RESULTS

Spindle cell proliferation was positive for vimentin, smooth muscle cell actin and D2-40 and negative for the other markers. Low proliferative index, assessed by Ki67, was found. Based on morphological and immunohistochemical findings we diagnosed this case as intranodal palisaded myofibroblastoma and we highlighted a D2-40 expression in the tumor spindle cells. The presence of mast cells and their particular distribution inside the tumor are also, together with D2-40 expression, original findings of this study. No therapy was recommended after surgical and histopathological evaluation. The evolution of the patient was favorable with no other relapse following surgical removal of the lymphadenopathy. He has a normal life and no other changes of clinical and biological parameters were registered.

CONCLUSION

To the best of our knowledge, this is the first report regarding a D2-40-positive reaction in the spindle cells of intranodal palisaded myofibroblastoma. Thus, D2-40 could be added to the panel of antibodies used for immunohistochemical diagnosis of such types of tumors.

Prox 1, VEGF-C and VEGFR3 expression during cervical neoplasia progression as evidence of an early lymphangiogenic switch

Prox1 is a key regulator of lymphatic endothelial cell commitment during embryonic development. No correlations between Prox1 and VEGF-C/VEGFR3 expression in cervical cancer has been done until now. The aim of the present study was to evaluate the peculiarities of Prox1, VEGF-C and VEGFR3 expression during uterine cervix neoplasia progression. Material and methods. One hundred and four specimens taken from women with macroscopically detectable lesions were classified by histopathology and analyzed by immunohistochemistry for Prox1, VEGFR3 and VEGF-C expression. Results. The presence of Prox1 nuclear expression was detected starting from CIN2 and CIN3 lesions to microinvasive carcinoma, in the nuclei of lymphatic and venous endothelial cells and scattered stromal cells. All Prox1 positive lymphatic vessels were positive for VEGFR3. A significant correlation was found between expression of VEGF-C in tumor cells and nuclear density of Prox1 positive lymphatic cells (p=0.044). Conclusion. The commitment of Prox1 positive cells through a lymphatic lineage is an early event for cervical neoplastic progression, being present starting with intraepithelial cervical lesions, and is strongly associated with VEGFR3 and VEGF-C expression. These findings suggest an early active lymphangiogenesis during cervical neoplasia progression and explain, in part, the early presence of lymph node metastasis in cervical cancer. By the detection of Prox1 expression in lymphatic and venous endothelial cells, and also in stromal cells, it has been suggested that there are at least three different mechanism of lymph vessel development during cervical neoplasia progression.

Behavior of the P1.HTR mastocytoma cell line implanted in the chorioallantoic membrane of chick embryos

The P1.HTR cell line includes highly transfectable cells derived from P815 mastocytoma cells originating from mouse breast tissue. Despite its widespread use in immunogenic studies, no data are available about the behavior of P1.HTR cells in the chick embryo chorioallantoic membrane model. The objective of the present investigation was to study the effects of P1.HTR cells implanted on the chorioallantoic membrane of chick embryos. We inoculated P1.HTR cells into the previously prepared chick embryo chorioallantoic membrane and observed the early and late effects of these cells by stereomicroscopy, histochemistry and immunohistochemistry. A highly angiotropic and angiogenic effect occurred early after inoculation and a tumorigenic potential with the development of mastocytoma keeping well mast cells immunophenotype was detected later during the development. The P1.HTR mastocytoma cell line is a good tool for the development of the chick embryo chorioallantoic membrane mastocytoma model and also for other studies concerning the involvement of blood vessels. The chick embryo chorioallantoic membrane model of mastocytoma retains the mast cell immunophenotype under experimental conditions and could be used as an experimental tool for in vivo preliminary testing of antitumor and antivascular drugs.

Everolimus dual effects of an area vasculosa angiogenesis and lymphangiogenesis

Recently approved as treatment for astrocytoma, kidney and pancreatic cancer, everolimus acts on tumor cells by inhibiting tumor cell growth and proliferation, as well as by inhibition of angiogenic activity by both direct effects on vascular cell proliferation and indirect effects on growth factor production. The effects of everolimus on early stages of normal vasculogenesis, angiogenesis and lymphangiogenesis are not yet available. We found increased development of intravascular pillars by using area vasculosa of the chick chorioallantoic membrane treated with everolimus. An active lymphangiogenic response was highlighted by the expression of Prospero homeobox protein 1 (Prox1) and podoplanin, together with vascular endothelial growth factor receptor C (Vegf-C) and vascular endothelial growth factor receptor 3 (Vegfr-3) expression on day 4 in the treated group. These findings suggest a potential role of everolimus in the activation of lymphangiogenesis.

Assessement of angiogenesis reveals blood vessel heterogeneity in lung carcinoma

Despite advances in treatment, the prognosis for lung cancer patients remains poor. Angiogenesis appears to be a promising target for lung cancer therapy; however, the clinical significance of vascular changes are not completely understood. The aim of this study was to evaluate the types and morphology of blood vessels in various lung carcinomas. Using double immunostaining, we investigated 39 biopsies from patients admitted with various histological types of lung carcinoma. Tumor blood vessels were quantified separately for CD34/smooth muscle actin and described as either immature, intermediate or mature. Double immunostaining evaluation of the type of blood vessels in lung carcinomas revealed a marked heterogeneity. The immature and intermediate type of vessels were more common in adenocarcinomas (ADCs) and squamous cell carcinomas (SCCs) of the lung. Small cell lung carcinomas revealed a significant correlation between pathological and immature types of blood vessels. Therefore, quantifying the types of tumor vessels in lung carcinomas may be an important element to improve the results of anti-vascular therapy.

Endothelial cell activation and proliferation in ovarian tumors: two distinct steps as potential markers for antiangiogenic therapy response

Ovarian cancer is the second leading cause of cancer-related death in women worldwide. Since most patients are diagnosed in advanced disease stages, the starting point, early steps and molecular mechanisms of ovarian cancer angiogenesis are still incompletely characterized. Most immunohistochemical studies for assessment of microvessel density (MVD) in ovarian tumors are based on CD31, CD34 and CD105 immunostaining of tumor blood vessels. Yet, the proliferative status of tumor blood vessel endothelial cells has not as yet been used in the assessment of tumor blood vessels. The present study investigated the Ki67 proliferative index of tumor blood vessel endothelial cells highlighted with the CD34 panendothelial marker and the CD105 endothelial marker in ovarian cancers by antigen co-localization with a doublestaining immunohistochemical method. Lack of co-localization of CD105 and Ki67 in all types of ovarian tumors together with the presence of CD34+/Ki67-positive endothelial cells suggest that endothelial cell activation and proliferation are distinct steps in ovarian tumors. Differences in the proliferation index were observed in endothelial cells from blood vessels of the tumor core and those of the tumor peripheral zones. Potential specific targeting of activated and proliferating tumor blood vessels may provide clues for improving antiangiogenic therapy efficiency.

Characterization of endoglin and Ki-67 expression in endothelial cells from benign and malignant lesions of the uterine cervix

Activation of endothelial cells is often associated with the cellular proliferation in vitro. CD105 is a more specific marker of activated endothelial cells from tumor vessels and Ki-67 is used to assess the proliferation status of both tumor and endothelial cells. The aim of the present study was to evaluate the status of endothelial cells using CD105 and Ki-67 immunohistochemistry in benign and malignant lesions of the uterine cervix. Double stain for CD105/Ki-67 in benign and malignant lesions of the uterine cervix showed that these two markers had divergent expression on endothelial cells from associated tumor blood vessels dependent on lesion type and proliferation status of tumor cells. Absence of CD105/Ki-67 coexpression in endothelial cells was correlated with histopathology of the uterine cervix lesions and tumor proliferative status. The present findings suggest that CD105 expression is an early event, specific for premalignant lesions of the uterine cervix, while endothelial proliferation assessed on Ki-67 combined with the lack of CD105 expression is often associated with invasive cervical carcinoma.

Paraganglioma-like dermal melanocytic tumor: a case report with particular features

Childhood dermal tumors with melanocytic features is an unusual tumor that can create diagnostic confusion. Among them, paraganglioma-like melanocytic tumors- previous included in melanocytic tumors of uncertain malignant potential- has some particular histopathologic and immunohistochemical features. We describe a case of 13 years old girl with a paraganglioma-like dermal melanocytic tumor of the left leg.

CD105/smooth muscle actin double immunostaining discriminate between immature and mature tumor blood vessels

The aim of the study was to demonstrate the value of the double immunostaining for endothelial and perivascular cell to discriminate mature from immature tumor-associated blood vessels in mammary carcinoma. We used the specific endothelial marker CD105 to highlight the activated endothelial cells and antibodies against smooth muscle cell actin (SMA) for perivascular cells, applying Envision Doublestain system (HRP/DAB-APAAP/Fast Red). We found an inverse correlation between the immunoexpression of CD105 and SMA in normal vessels and a strong positive signal for CD105 in the intratumor single endothelial cells and immature vessels. Only few blood vessels were positive for both CD105 and SMA within the tumor area. The signal for the endothelial marker was weak and inconstant, and significantly diminished when the SMA immunoexpression was increased for the same vessel. The differentiation between vessels with and without perivascular cells coverage using double immunostaining for CD105/SMA may be an important step in the selection of the mammary tumors, which could have a high grade of responsiveness to antiangiogenic therapy with monoclonal antibodies against CD105 antigen.

Lymphatic vessels identified with podoplanin. Comparison of immunostaining with three different detection systems

The aim of the study was to find the optimal immunostaining protocol for monoclonal mouse anti human podoplanin antibody clone 18H5, which is less studied. We tested three detection systems for different antibody dilutions and antigen retrieval methods applied on normal and tumor breast tissues, lip squamous cell carcinoma, kidney tumors and testis carcinoma. The interpretation was linked to the background staining, specificity for the lymphatic endothelium and cross-reactivity. The ABC method gave a high background even the antibody dilution was increased. No immunostaining was obtained with Envision detection system for any dilution or type of antigen retrieval. We obtained the best results using LSAB+ working system for an antibody dilution of 1:500 with no background and podoplanin expression was restricted to the lymphatic endothelium. We consider that the standardization of immunostaining protocol is the first step for an optimal interpretation of the podoplanin expression using less studied antibody clones.

Diagnostic significance of the immunoexpression of CD34 and smooth muscle cell actin in benign and malignant tumors of the breast

PURPOSE

Our aim was to investigate the distribution of CD34 and smooth muscle cell actin positive myofibroblasts in the stroma of the normal mammary gland, benign and malignant tumors. The observations were especially focused on the diagnostic value of the cumulative results obtained with these immunoreactions.

METHODS

Our study included 112 female patients with suspect breast masses obtained by surgery or biopsy. We performed morphological study and immunohistochemistry for CD34 and SMA.

RESULTS

We have found normal breast tissue, sclerosing adenosis, fibroadenomas, fibrocystic diseases, phyllodes tumor, DCIS, ductal invasive, lobular, squamous, medullary, mucinous, and papillary carcinomas. We also found apocrine metaplasia, florid ductal hyperplasia, atypical hyperplasia, papilloma and LCIS associated with the malignant tumors. All the normal breast tissues and most of benign lesions were positive for CD34 and negative for SMA. The exceptions were represented by a case of fibroadenoma and the phyllodes tumor, with CD34 positivity and a focal acquisition of SMA; fibrocystic disease with associated apocrine metaplasia adjacent to a squamous carcinoma with loss of CD34 expression and focal acquisition of SMA. All our DCIS and invasive carcinomas have lost CD34 expression and gained SMA positivity. Some particular behavior had the mucinous and squamous carcinomas.

CONCLUSIONS

Although there were some exceptions especially when one of the two markers was interpreted separately and in some cases associated with sclerotic stroma, we conclude that the combined expression of CD34 and a-SMA is of potential diagnostic value in the distinction between benign and malignant tumors in some difficult cases.