Biomedical subjects

Józef Tazbir

Publications and source records attributed to Józef Tazbir.

4 recordsLinked to original sources

PubMed2006

Influence of L-thyroxine administration on poor-platelet plasma VEGF concentrations in patients with induced short-term hypothyroidism, monitored for thyroid carcinoma.

Angiogenesis is a process of new blood vessel development from pre-existing vasculature. It is a crucial process in normal physiology, as well as in several pathological conditions. The vascular endothelial growth factor (VEGF) represents a family of specific endothelial cell mitogens, involved in normal angiogenesis and in tumour development. The aim of the present study was to estimate the influence of L-thyroxine (L-T4) administration on poor-platelet plasma (P-PP) VEGF concentrations in patients with induced short-term hypothyroidism, monitored for differentiated thyroid carcinoma. In the present study, P-PP concentrations of VEGF, thyroglobulin, thyrotropin and free thyroid hormones were investigated in a population of 24 hypothyroid patients, who were withdrawn from L-T4 treatment for 5 weeks and studied before and after 2 months of L-T4 therapy. Only healthy female patients with no evidence of metastasis in whole body scintigraphy were included in the study. They were then compared with 20 healthy control subjects, matched for age, sex and body mass index (BMI). The patients had significantly lower plasma VEGF concentrations before treatment with L-T4 than after administration of that hormone. There was no significant difference in plasma VEGF levels, either between the patients treated with L-T4, and the controls, or between the patients untreated with L-T4, and the controls. Even short-time changes in thyrometabolic profile exert an important influence on P-PP VEGF concentrations, even if there is no thyroid tissue.

Blood Platelets↗

PubMed2005

Patterns of cyclin E, retinoblastoma protein, and p21Cip1/WAF1 immunostaining in the oncogenesis of papillary thyroid carcinoma.

PURPOSE: Uncontrolled cell proliferation, a hallmark of cancer, may result from an increased expression of cell cycle up-regulators, and/or from a reduced expression of cell cycle down-regulators. In the present study, we analyzed, by immunohistochemistry, the expression of a panel of three proteins: cyclin E and two cell cycle inhibitors, p21(Cip1/WAF1) and retinoblastoma protein (pRb) product, in different stages of papillary thyroid carcinomas (PTC). EXPERIMENTAL DESIGN: We investigated immunostaining patterns of the proteins in question in 51 resected PTC in pathologic stages, ranging from pT(1a) to pT(4), taking into consideration their relation to clinicohistopathologic factors. RESULTS: We observed a significant, progressive loss of expression of p21(Cip1/WAF1) with advancing tumor grade. The differences reached values of significance between pT(1a) [papillary thyroid microcarcinomas (PMC)] and pT(2) and between PMC and pT(4) stages of PTC. pRb presented a similar immunostaining pattern to that of p21(Cip1/WAF1) and the differences reached values of significance between pT(1a) and pT(2), and between PMC and pT(4) stages of PTC. The results of cyclin E immunostaining corresponded to our recently published result, and a negative correlation was observed between the immunostaining index of cyclin E and pRb. CONCLUSIONS: The results of the present study suggest that cyclin E expression and suppression of pRb and p21(Cip1/WAF1) may be characteristic patterns of immunostaining for PTC with a tendency to early metastasizing. If our results are confirmed in a larger study, the diagnostic panel, constructed of the antibodies against these proteins, may become a valuable tool in predicting the metastatic potential in PTC.

Carcinoma, Papillary↗

PubMed2005

Selective embolization of thyroid arteries (SETA) as a palliative treatment of inoperable anaplastic thyroid carcinoma (ATC).

OBJECTIVES: Anaplastic thyroid carcinoma (ATC) is one of the most aggressive solid tumors in humans. Despite intense application of multimodality of treatment with surgery and/or external beam radiotherapy and chemotherapy, the survival rates remain low--generally the mean survival is about six (6) months after diagnosis. Rapid development--particularly over the last decade--of interventional radiology, provides methodology that allows examining thyroid arterial embolization as an alternative approach to ablating thyroid tissue. The aim of the present study was to evaluate selective embolization of the thyroid arteries (SETA) as a possible alternative for the palliative treatment of advanced, inoperable ATC. PATIENTS AND METHODS: The study group comprised five (5) patients with advanced stage of inoperable ATC. All the patients underwent SETA of the superior and/or inferior thyroid arteries. SETA was performed using polyvinyl alcohol particles, ranging from 500-710 microm in diameter. After SETA, selective angiography of thyroid arteries was performed to ensure that the targeted arteries were completely occluded. CONCLUSIONS: The results of the present study suggest that SETA is minimally invasive and save method of palliative treatment of ATC and, as such, may be recommended in cases of intractable hemorrhage and pain caused by ATC progression.

Aged↗

PubMed2004

Cyclin E expression in papillary thyroid carcinoma: relation to staging.

Cyclin E plays a pivotal role in the regulation of G1-S transition and relates to malignant transformation of the cells. However, the clinical significance of cyclin E expression in patients with papillary thyroid carcinoma (PTC) remains unknown. We examined by immunohistochemistry the expression of cyclin E in 41 resected PTCs in pathologic stages from pT1a to pT4 and analyzed its relation to clinicohistopathologic factors. The positive staining was divided into 3 grades: no expression if less than 10%, expression if 11-50% and overexpression if more than 50% of the nuclei of tumor cells were stained positively. Cylin E expressions were observed in 75.6% of analyzed PTCs but only 60% of papillary microcarcinomas (PMCs) were immunopositive for cyclin E expression. However, cyclin E staining was observed in 90.4% of PTCs in a group with TNM higher than pT1a. The staining index was significantly different between the PMCs and the rest of the cancers investigated (14.91% +/- 14.4% vs. 34.03% +/- 23.44%, respectively; p < 0.005) and we observed positive relation between the staining index and factor T of staging of PTCs. All the lymph node metastases coexisted with cyclin E expression and most, but not all, of them coexisted with cyclin E overexpression. These findings indicate that cyclin E may play a key role for the oncogenesis and biologic behavior of PTC. If our results are confirmed in a larger study, a high level of cyclin E expression may become a new prognostic marker for PTCs.

Carcinoma↗