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Anna Batistatou

Publications and source records attributed to Anna Batistatou.

33 records · Page 2Linked to original sources
PubMed2005

Potential autocrine function of vascular endothelial growth factor in head and neck cancer via vascular endothelial growth factor receptor-2.

Vascular endothelial growth factor is a peptide with well-defined actions on the vasculature and fundamental role in tumor angiogenesis. Its action in vascular endothelium is exerted in a paracrine manner. The immunohistochemical expression of this protein by cancer cells in head and neck squamous cell carcinoma was correlated with increased tumor aggressiveness and poor survival in previous studies. In the past years, an increasing amount of studies demonstrated potential autocrine action of vascular endothelial growth factor in various neoplasms. However, the existence and the impact of such autocrine action in head and neck cancer have not been demonstrated yet. In this retrospective study, we evaluated the expression of vascular endothelial growth factor and its receptors in neoplastic cells, in a cohort of patients with head and neck squamous cell carcinoma, and compared this expression with tumor aggressiveness, clinicopathologic parameters and outcome. High expression of vascular endothelial growth factor was strongly correlated with high expression of vascular endothelial growth factor receptor-2 (but not vascular endothelial growth factor receptor-1) on the cancer cells (P<0.001). The co-overexpression of both the protein and vascular endothelial growth factor receptor-2 was associated with higher tumor proliferation rate (P<0.001). The above co-overexpression also correlated with worse survival (log rank P<0.05) in patients with oral-larynx squamous cell carcinoma. Our results suggest that an autocrine vascular endothelial growth factor loop, mediated via vascular endothelial growth factor receptor-2, probably exists in head and neck squamous cell carcinoma. These observations support the hypothesis that the use of vascular endothelial growth factor receptor-2 inhibitors as adjuvant antiangiogenic therapy might have beneficial effects for these patients, by disrupting both paracrine (endothelial-dependent) and autocrine actions of vascular endothelial growth factor.

Adult↗
PubMed2005

Integrin receptors and extracellular matrix components in parotid neoplasms.

In the review, the role of integrin receptors as well as of some of their ligands of the extracellular matrix in cases of parotid neoplasms is discussed, in particular, the data concerning the expression of various types of integrin adhesion molecules in benign and malignant tumors of the parotid, the expression of fibronectin, tenascin, and collagen type IV etc. The role of dysregulation of the expression of these proteins in invasion and metastasis of parotid tumors is discussed.

Animals↗
PubMed2005

Integrins adhesion molecules and some of their ligands in laryngeal cancer.

In this review data regarding the regular expression and distribution of integrins adhesion molecules as well as some of their ligands in cases of squamous cell carcinoma of the larynx (LSCC) are discussed. Cancer of the larynx is one of the most common malignancies of the head and neck. Upon neoplastic transformation several alterations of the integrins adhesion molecules and extracellular matrix (ECM) components are observed, i.e. the loss of the normal architecture especially depolarization of some integrins, like alpha6beta4, alpha3beta1, alpha2beta1 as well as the presence of alpha6beta1 integrin in neoplastic epithelium. Furthermore, the upregulation of alpha5beta1 integrin is a negative prognostic factor. In cases of laryngeal cancer, disorganization of the basal membrane components (laminins 1 and 5, type IV collagen, tenascin, fibronectin isoforms) which represent integrins ligands, is found. This is due to partial or complete destruction of the basal membrane, thus, permitting extravasation and migration of cancer cells. These phenomena are observed in a greater degree in tumors showing poor prognosis. It seems that damage of these adhesion complexes is important in the neoplastic process. So, further studies are necessary to establish the importance of these markers to early larynx cancer diagnosis and reach the decision on appropriate therapeutic strategies in the management of those patients.

Animals↗
PubMed2004

Estrogen receptor beta (ERbeta) is expressed in brain astrocytic tumors and declines with dedifferentiation of the neoplasm.

PURPOSE: Estrogen receptor beta (ERbeta) is the second identified receptor mediating the effects of estrogen on target tissues. The role of ERbeta in cancer pathobiology is largely unknown, because specific antibodies have not been available until recently. Initial studies have shown that ERbeta expression declines in breast, ovarian, prostatic, and colon carcinomas. Tamoxifen, a synthetic anti-estrogen compound that is a mixed agonist/antagonist of estrogen receptor alpha (ERalpha) and a pure antagonist of ERbeta, has moderate beneficial effects in human astrocytic neoplasms. However, most published studies agree that glial tumors do not express ERalpha. The purpose of this study was to explore the expression of ERbeta in astrocytic neoplasms. METHODS: ERbeta expression was monitored immunohistochemically in 56 cases of astrocytomas of all grades (grade I-IV) and in adjacent non-neoplastic brain tissue. RESULTS: Moderate or strong nuclear immunopositivity was obtained in non-neoplastic astrocytes and in low-grade astrocytomas, whereas the majority of high-grade tumors were immunonegative or displayed weak immunoreactivity. The progressive decline in ERbeta expression paralleled the increase in tumor grade. CONCLUSIONS: In as much as ERbeta is possibly the only ER expressed in astrocytes, its decreased expression may play an important role in astrocytic tumor initiation and in the potential response of glial neoplasms to tamoxifen.

Adolescent↗
PubMed2004

Mitoses and cancer.

Mitoses are coupled to cell proliferation. In non-neoplastic cells they are usually symmetric and typical and lead to increase in cell number. Cancer cells are notorious for their asymmetric divisions, which are considered to reflect abnormalities due to disordered growth. The centrosome controls the mitotic activity and it has been proposed that centrosomal defects possibly contribute to carcinogenesis and aneuploidy of cancer cells. So far the atypical mitoses often seen in neoplastic cells are not considered unique. However careful observation of atypical mitoses in various neoplasms revealed that although they were indeed "atypical" they resembled each other within the same tumor and were different from those of other tumors. It is proposed that specific centrosomal alterations, which lead to a limited variety of atypical mitotic figures in each neoplasm, are not a random result but a distinct event that is possibly involved in carcinogenesis.

Centrosome↗
PubMed2004

Immunohistochemical expression of vascular endothelial growth factor (VEGF) and C-KIT in cutaneous melanocytic lesions.

Vascular endothelial growth factor (VEGF) and C-KIT are involved in tumor progression in several human neoplasms. The aim of the present study has been to investigate their immunohistochemical expression in melanocytic lesions. We examined 11 compound nevi, 12 dysplastic nevi, and 18 melanomas. Immunostaining for VEGF was observed only in melanomas; c-kit expression was detected in melanomas (higher in radial than in vertical growth phase) and in nevi (predominantly in the junctional component). Our data indicate that assessment of VEGF expression might aid in the differential diagnosis between dysplastic nevi and melanomas. Moreover, VEGF might be a candidate for targeted therapy. The loss of c-kit expression might contribute to melanoma progression.

Biomarkers, Tumor↗
PubMed2003

Potential role of bcl-2 and ki-67 expression and apoptosis in colorectal carcinoma: a clinicopathologic study.

Colorectal cancer is associated with deregulation of apoptotic and proliferative processes. The purpose of this study was to investigate the presence of apoptosis and proliferation in colorectal cancer and evaluate their possible correlation with classic prognostic markers and patients' survival. Tumors from 117 patients, followed for 44-142 months, were studied immunohistochemically using the anti-bcl-2 and anti-Ki-67 antibodies. Apoptotic body index (ABI) was assessed by a standard TUNEL method. The bcl-2 protein was detected in 65% of adenocarcinomas with increased expression in low-grade and early-stage tumors. No association was noted between bcl-2 expression and proliferative activity, ABI, or patients' survival. A positive correlation was observed between ABI and proliferation (P < 0.05). Apoptosis was more frequently observed in advanced tumor stage or high-grade neoplasms. Cox analysis revealed that only tumor stage and grade constituted independent prognostic factors. The study suggests that there is a possible deregulation of the mechanisms that control bcl-2 expression in high-grade and advanced-stage colorectal carcinomas. Regulation of apoptosis is a complex phenomenon and other factors, including tumor heterogeneity, may be involved.

Adenocarcinoma↗
PubMed2002

S-100 protein+ dendritic cells and CD34+ dendritic interstitial cells in thyroid lesions.

Dendritic cells (DCs) are antigen-presenting cells and mature from precursor CD34+ stromal cells (dendritic interstitial cells [DICs]) or monocytes. The aim of the present study was to gain insight into the local immune response to various thyroid lesions. We investigated, immunohistochemically, the presence of S-100+ DCs and CD34+ DICs in 13 papillary carcinomas, 10 follicular carcinomas, 7 follicular adenomas, 1 Hurthle cell carcinoma, 1 Hurthle cell adenoma, 2 medullary carcinomas, 6 undifferentiated carcinomas, and 3 nodular goiters. Dense infiltrates of S-100+ DCs were noted in the majority of papillary carcinomas (mean: 66.4), while moderate infiltrates were observed in follicular adenomas (mean: 23.3), follicular carcinomas (mean: 23.5), and undifferentiated carcinomas (mean: 31.6). The remaining lesions showed slight infiltrates of scattered DCs. DICs were noted exclusively in neoplastic lesions, specifically at the periphery and within the tumor capsule. The increased number of DCs in papillary carcinomas is possibly correlated with their good prognosis. The specific distribution of DICs suggests a possible contribution to growth regulation of thyroid neoplasms.

Adenoma↗
PubMed2002

Immunohistochemical expression of TGF-beta1, p21WAF1, p53, Ki67, and angiogenesis in gastric carcinomas: a clinicopathologic study.

BACKGROUND: Transforming growth factors-beta (TGF-betas) are multifunctional polypeptides with crucial role as regulators of cellular growth and differentiation. It has been reported that TGF-beta1 plays a biphasic action on tumorigenesis thus inducing or inhibiting malignant properties of the epithelial cells. METHODS: TGF-beta1 expression was analyzed in 56 patients with gastric carcinoma by immunohistochemical methods and compared with the expression of p21, p53, and Ki67, as well as with angiogenesis. The correlation of these markers with clinicopathological parameters was also evaluated. RESULTS: TGF-beta1 expression was detected in 71% of tumors and was more frequent in adenocarcinomas of the intestinal type (p < 0.001). Positivity of p21WAF1, and p53 was observed in 32% and 51% of the tumors, respectively. A high Ki67 proliferating index was detected in 53.5% of the tumors. TGF-beta1 expression was significantly correlated with p21 expression (p < 0.001) and was inversely correlated with microvessel density. p21 expression was also higher in tumors with low proliferating index (p < 0.01). There was no apparent correlation between the expression of these markers and tumor stage, depth of invasion, or lymphnode metastases. CONCLUSION: The findings show that TGF-beta1 may be involved in the activation of the cdk inhibitor p21WAF1 in gastric adenocarcinomas, suggesting p53-independent induction of p21 in gastric cells. TGF-beta1 does not seem to contribute to the alteration of the angiogenic status of these tumors.

Adenocarcinoma↗
PubMedDate not supplied

Expression of CD44 protein in renal cell carcinomas: association with p53 expression.

CD44 is an adhesion molecule involved in cell-to-cell and cell-to-matrix interactions. Recent evidence indicates a role of CD44 in tumor growth and metastatic potential of tumor cells. Moreover, it is widely known that the p53 tumor suppressor gene controls cell proliferation and loss of its normal function may lead to carcinogenesis. To investigate the role of these biomarkers in renal cancer, we analyzed the immunohistochemical distribution of CD44's expression on formalin fixed paraffin embedded tissue from 67 renal cell carcinomas and correlated with clinicopathologic parameters as well as with p53 suppressor gene expression. The monoclonal antibodies CD44 and p53 were applied to the tissues using the streptavidin biotin peroxidase method after microwave antigen retrieval. For CD44 and p53 more than 10% membranous and 5% nuclear staining, respectively, were estimated as positive. CD44's membranous immunoreactivity was detected in 24/67 tumors (35%) and mostly in carcinomas of clear/granular cell type. Nine tumors expressed nuclear immunoexpression of p53 protein (13.4%). Statistically significant correlation was noted between CD44 expression and nuclear grade (P < 0.001), tumor stage (P < 0.001), vascular invasion (P < 0.05) and p53 expression (P < 0.01). These results suggest that CD44s and p53 are markers of tumor progression in renal cell cancer.

Adult↗
PubMedDate not supplied

The usefulness of p63 as a marker of breast myoepithelial cells.

The identification of an outer layer of myoepithelial cells is a valuable clue in the differential diagnosis of breast lesions. Myoepithelial cells can usually be appreciated with standard hematoxylin-eosin stains, however in pathology practice one encounters difficult cases, particularly in core biopsy specimens. There are several reported markers for the immunohistochemical detection of myoepithelial cells. Smooth muscle specific proteins, such as smooth muscle actin, smooth muscle myosin heavy chain, calponin and h-caldesmone are utilized to highlight myoepithelium. Smooth muscle actin is the most commonly used and has been established as a specific and sensitive marker. However, sometimes the staining can not be interpreted, since actin stains stromal fibroblasts and vascular smooth muscle cells as well. S100 protein and specific cytokeratins (keratins 5,7,14 and 17) also stain myoepithelial cells, but the staining is not specific and is not optimally sensitive. Maspin and CD10 are relatively new and promising markers. The nuclear protein p63 has attracted much attention in recent reports. p63-positive myoepithelial cells have been shown to surround benign epithelial lesions and form a consistent, although discontinuous, rim around epithelial cells in carcinomas in situ. No staining has been noted in infiltrative carcinomas. p63-immunostaining is nuclear and so it is easily appreciated, even in cytologic preparations. It is also highly specific since neither stromal fibroblasts nor vascular smooth muscle cells are stained. In conclusion, it appears that p63 is a sensitive and specific myoepithelial marker and may be included in immunohistochemical panels aiming at identifying myoepithelial cells in problematic breast lesions.

Biomarkers, Tumor↗
PubMedDate not supplied

Expression of vascular endothelial growth factor (VEGF) and association with microvessel density in benign prostatic hyperplasia and prostate cancer.

BACKGROUND: Tumor angiogenesis is an absolute requirement for tumor growth and a prognostic factor for various malignant neoplasms. Recent reports in the literature have addressed the importance of the VEGF system in benign prostatic hyperplasia (BPH) and adenocarcinoma, however the results are controversial. The aim of the present study was to determine and compare the levels of VEGF expression and vascularity in BPH and prostate carcinoma. MATERIALS AND METHODS: We examined 60 prostate adenocarcinomas and 64 benign prostatic hyperplasias. Angiogenesis was estimated by determining microvessel counts (MVC), with the use of anti-CD31 and anti-CD34 antibodies. Expression of VEGF was also evaluated immunohistochemically. RESULTS AND CONCLUSION: Our data showed that angiogenesis was more prominent in carcinomas than in BPH. Furthermore, increased MVC was significantly associated with high-grade carcinomas. Angiogenesis was correlated with VEGF expression and it was, at least in part, mediated by the latter. Thus, prostate adenocarcinoma may represent a suitable neoplasm for antiangiogenic treatment in combination with conventional therapies.

Adenocarcinoma↗
PubMedDate not supplied

Expression of mismatch repair proteins in invasive and in situ carcinoma of the breast.

BACKGROUND: Genetic instability is a characteristic feature of familial and sporadic breast carcinomas. It is not clear whether defects in the mismatch repair system accompany this instability. The purpose of this study was to explore the expression of two of the proteins encoded by the DNA mismatch repair genes, namely MLH1 and MSH2, in sporadic in situ and invasive breast carcinomas of various types and grades occurring in Greek patients. MATERIALS AND METHODS: MLH1 and MSH2 expression was monitored immunohistochemically in 60 breast carcinomas (20 in situ and 40 invasive). RESULTS-CONCLUSION: Although we did not detect loss of MLH1 or MSH2 expression, we do believe that our data will contribute to a better understanding of the role of the mismatch repair (MMR) system in breast cancer.

Adaptor Proteins, Signal Transducing↗