Biomedical subjects

Wanda M Krajewska

Publications and source records attributed to Wanda M Krajewska.

10 recordsLinked to original sources

PubMed2006

Genetic instability in the RAD51 and BRCA1 regions in breast cancer.

Breast cancer is the most prevalent cancer type in women. Accumulating evidence indicates that the fidelity of double-strand break repair in response to DNA damage is an important step in mammary neoplasias. The RAD51 and BRCA1 proteins are involved in the repair of double-strand DNA breaks by homologous recombination. In this study, we evaluated loss of heterozygosity (LOH) in the RAD51 and BRCA1 regions, and their association with breast cancer. The polymorphic markers D15S118, D15S214 and D15S1006 were the focus for RAD51, and D17S855 and D17S1323 for BRCA1. Genomic deletion detected by allelic loss varied according to the regions tested, and ranged from 29 to 46% of informative cases for the RAD51 region and from 38 to 42% of informative cases for the BRCA1 region. 25% of breast cancer cases displayed LOH for at least one studied marker in the RAD51 region exclusively. On the other hand, 31% of breast cancer cases manifested LOH for at least one microsatellite marker concomitantly in the RAD51 and BRCA1 regions. LOH in the RAD51 region, similarly as in the BRCA1 region, appeared to correlate with steroid receptor status. The obtained results indicate that alteration in the RAD51 region may contribute to the disturbances of DNA repair involving RAD51 and BRCA1 and thus enhance the risk of breast cancer development.

Adult↗

PubMed2006

Loss of heterozygosity and microsatellite instability at RAD52 and RAD54 loci in breast cancer.

This study was carried out to evaluate the loss of heterozygosity (LOH) and microsatellite instability (MSI) in breast cancer, in the 12p13.3 and 1p32 chromosomal regions where RAD52 and RAD54 genes are localized. Polymorphic markers D12S98, D12S1698 for RAD52 and D1S209, D1S411 for RAD54 were used. Relationships between LOH and clinicopathological parameters, i.e. tumor type and grade, patient's age, steroid receptors status and lymph node and distal metastases were assessed. For alleles frequency estimation 100 primary breast cancers were tested. DNA isolated from paraffin-embedded tissues and their matched blood samples were analyzed for PCR-based LOH and MSI by fluorescence-based DNA sequencing technology. In analyzed cases LOH was found in 14% and 11% of informative cases for D12S98 and D12S1698 markers, respectively and in 18% and 17% of informative cases for D1S209 and D1S411 markers, respectively. The highest frequency of MSI was identified at loci D12S98 (10%) and D1S209 (11%). Significant correlations between RAD52 and RAD54 regions with concomitant LOH and histological type and progesterone receptor status were observed. In the case of RAD54 further correlations with respect to tumor grade and the presence of distal metastases were noticed.

Adult↗

PubMed2004

TGF-beta signaling is disrupted in endometrioid-type endometrial carcinomas.

OBJECTIVE: Previous studies have demonstrated deregulation of the expression and changes in the intracellular distribution of TGF-beta pathway components in human endometrial cancer (EC). The aim of this study was to assess the relationship between the expression of TGF-beta cascade components, including TGF-beta receptor type I (TGF beta RI) and type II (TGF beta RII), SMAD2, SMAD3, SMAD4, and clinicopathological features--tumor grade, FIGO classification, and depth of myometrial invasion--of type I (endometrioid-type) ECs to give some insight into the role of TGF-beta cascade components in endometrial tumorigenesis. METHODS: The expression of TGF beta RI, TGF beta RII, SMAD2, SMAD3, and SMAD4 was evaluated both at the mRNA and protein level using reverse transcription polymerase chain reaction (RT-PCR) and ELISA, respectively. RESULTS: Infiltrating endometrial carcinomas (less and more than half of the myometrial wall thickness) express significantly higher TGF beta RII protein level compared with non-infiltrating tumors (P = 0.04 and P = 0.01, respectively). Decreased level of SMAD2 and SMAD4 mRNAs was observed in the uterine tumors infiltrating less and more than half of the myometrial wall (P = 0.03 and P = 0.02, respectively) compared with noninfiltrating ECs. Significantly higher SMAD4 protein level in the cytoplasmic fraction of ECs was found when tumor grade and depth of myometrial invasion were considered (P < 0.05). Generally, tumor progression was associated with a decreased number of cases characterized by the presence of SMADs in the nuclear fraction only. CONCLUSION: Our data suggest that disturbances of the TGF beta RII and SMAD4 expression as well as localization of SMADs may be important to the infiltration of the myometrial wall by the type I endometrial carcinomas.

Activin Receptors, Type I↗

PubMed2004

Androgen receptor versus erbB-1 and erbB-2 expression in human prostate neoplasms.

A subject of current interest, especially in the development of androgen refractory prostate cancer, is the androgen receptor (AR) activation by growth factor receptors. Here, we report our work on the measurement of AR mRNA and protein expression in benign prostatic hyperplasia (BPH) and prostatic carcinoma (PCA) and evaluation of the relationship between AR, erbB-1 and erbB-2 gene expression determined in the same tissue. In order to define AR, erbB-1 and erbB-2 in human prostate neoplasms 36 benign prostatic hyperplasia, 46 prostatic carcinoma and 12 normal prostate gland samples were analysed. According to distant metastasis PCA tissues were divided into two categories: i) T1-4N0-3M0 (25 samples) and ii) T4N2-3M1 (21 samples). AR, erbB-1 and erbB-2 mRNA expression was estimated by RT-PCR. AR protein expression, both in nuclear and cytoplasmic fractions, was measured by Western blot technique. The association of AR mRNA and protein expression with erbB-1 and erbB-2 gene expression was evaluated. It was found that in clinically invasive (group II of PCA) prostate cancer cases AR mRNA expression was significantly correlated with erbB-2 mRNA expression (Spearman R coefficient 0.86, p<0.05). Interestingly, AR protein expression in this group of PCA was determined mainly in nuclear fraction. By Western blot AR protein was identified in 76.0% (16/21) and 23.8% (5/21) of PCA group II nuclear and cytoplasmic fractions, respectively. Furthermore, the mean AR protein level in nuclear fraction of clinically invasive (group II) PCA (0.82+/-0.04) was significantly higher (p<0.05) as compared to the normal group (0.56+/-0.11). In the case of T4N2-3M1 samples, significant correlation between AR protein level in nuclear fraction and erbB-2 mRNA expression (Spearman R coefficient 0.53, p<0.05) was stated.

Adult↗

PubMed2004

Caveolins: structure and function in signal transduction.

The caveolin family proteins are typically associated with microdomains that are found in the plasma membrane of numerous cells. These microdomains are referred to as/called caveolae. Caveolins are small proteins (18-24 kDa) that have a hairpin loop conformation with both the N and C termini exposed to the cytoplasm. Apart from having a structural function within caveolae, these proteins have the capacity to bind cholesterol as well as a variety of proteins, such as receptors, Src-like kinases, G-proteins, H-Ras, MEK/ERK kinases and nitric oxide synthases, which are involved in signal transduction processes. Considerable data allow the assumption to be made that the majority of the interactions with signaling molecules hold them in an inactive or repressed state. The activity of caveolins seems to be dependent on its specific post-translation modifications. It is suggested that caveolins fulfill a role in the modulation of cellular signaling cascades.

Animals↗

PubMed2003

Genotyping of p53 codon 175 in colorectal cancer.

BACKGROUND: The gene encoding the tumor suppressor protein p53 is one of the most frequently mutated in human cancer. Over 8000 mutations of this gene have been identified. The spectrum of p53 mutations varies among tumor types. More than half of these mutations appear in three hotspot codons: 175, 248 and 273. The purpose of the present study was to evaluate the GgA transition in codon 175 of the p53 gene as a potential marker of colon cancer progression. MATERIAL/METHODS: The prognostic significance of alterations in codon 175 exon 5 of p53 gene was studied in 32 patients with colorectal cancer. The ASA-PCR method was used to assess GgA (ArggHis) transition in codon 175. RESULTS: The analyzed point mutation was identified in 56% of the tested cases of colorectal cancer. The frequency of codon 175 p53 gene mutation was found to increase with cancer aggressiveness. Screening for the studied point mutation in codon 175 showed no alteration in analyzed samples classified as Dukes' A stage, while variations were observed in 43%, 50% and 75% of the cases classified as Dukes' B, C, and D, respectively. In three cases the studied mutation was also found in some mucosal cells obtained from resectional borders. CONCLUSIONS: The GgA transition in codon 175 of the p53 gene may be useful as a potential marker of colorectal cancer progression and as a means of evaluating the margins of surgical resection.

Adult↗

PubMed2002

Expression of TGF-beta type I and II receptors in normal and cancerous human endometrium.

Transforming growth factor-beta (TGF-beta) belongs to a superfamily of structurally related polypeptides involved in various biological processes, including cell growth, proliferation and differentiation, angiogenesis, apoptosis, and extracellular matrix remodeling. We tried to define the different expression patterns of the TGF-beta receptors by investigating the female reproductive organs during the menstrual cycle and endometrial tumorigenesis, because their role in these processes is still unclear. In this study, we examined the expression of the TGF-beta type I and type II receptors in normal (n=13) and carcinomatous (n=42) endometrial tissue specimens using reverse transcriptase polymerase chain reaction and immunological (Western blot and enzyme linked immunosorbent assay) methods. Two uncommon female genital tract tumors, rhabdomyosarcoma of the uterine cervix and uterine carcinosarcoma, were also included. There were no significant differences between normal and cancerous endometrial tissues regarding the TGF-beta receptors mRNA levels. However, we observed a markedly low TGF-beta type I receptor protein level (P<0.028; Mann-Whitney-U test), while the malignant endometrium showed a significantly higher TGF-beta type II receptor protein level (P<0.007; Mann-Whitney-U test) than the normal endometrium. Moreover, significantly elevated TGF-beta receptor type II protein level was noted when depth of myometrial invasion of endometrial carcinomas was considered (P<0.05; Mann-Whitney-U test). In contrast to uterine carcinosarcoma, in which no detectable mRNA for TGF-beta type II receptor was found, we noted expression of both TGF-beta receptors in rhabdomyosarcoma of the uterine cervix. However, neither rhabdomyosarcoma of the uterine cervix nor uterine carcinosarcoma displayed TGFbetaRI and TGFbetaRII protein expression. This observation corroborates the complexity of the deregulation of TGF-beta receptor expression in human endometrial cancer.

Activin Receptors, Type I↗

PubMed2001

Androgen receptor status in female breast cancer: RT-PCR and Western blot studies.

PURPOSE: Although the androgen receptor (AR) has been found to be expressed in female breast tumours, its role in breast cancer remains unclear. In addition to the oestrogen receptor (OR) and progesterone receptor (PR), AR functional status may be important in the control of female breast cancer growth. METHODS: In order to define AR in breast cancer, 67 primary breast tumours and 8 normal breast samples as control tissue were analysed for AR expression at the mRNA and protein levels using RT-PCR and Western blotting, respectively. The association of AR expression with tumour size and axillary lymph node status was investigated. Expression of AR mRNA was compared with that of OR and PR. RESULTS: AR expression was identified in 66% (44/67) and 51% (34/67) of the cancers studied by RT-PCR and Western blotting, respectively. The number of positive samples and the level of AR mRNA were significantly higher among the cancer samples than among normal samples. No expression of AR protein was detected in normal breast tissue. A significant correlation between AR gene expression and its protein level in nuclei of carcinoma samples was demonstrated. The expression level of both AR gene and AR protein in nuclei was found to be positively correlated with tumour invasiveness. Of the breast carcinoma specimens, 44.8% (30/67) were OR-, PR- and AR-positive, while 14.9% (10/67) were steroid receptor-negative. However, 18% (12/67) of the primary breast tumours negative for OR and PR were positive for AR. CONCLUSIONS: The high incidence of AR expression in female breast tumours suggests a potential role of AR in breast cancer, in addition to OR and PR.

Adult↗

PubMedDate not supplied

Androgen receptor (AR) expression in normal and cancerous human endometrial tissues detected by RT-PCR and immunohistochemistry.

OBJECTIVE: This study aimed at assessing the expression and cellular localisation of the androgen receptor (AR) in normal and malignant human endometrial tissues. MATERIALS AND METHODS: Twelve normal endometrial samples and 25 uterine cancers were studied using RT-PCR and immunohistochemistry (IHC). RESULTS: One of the 12 (8%) normal endometrial samples showed AR PCR-product, whereas 4 of the 25 (16%) cancers displayed AR expression. Tumor tissues and normal tissues did not differ significantly in AR expression (p=0.66; Mann-Whitney U-test). Nuclear staining for AR was positive in 10 of the 25 (40%) cancers, in the glandular cancer cells, in the surrounding stroma and in the myometrium. There was a significant correlation between mRNA RT-PCR AR expression and the IHC AR staining in endometrial tumors (r=0.53; p=0.006). CONCLUSION: To the best of our knowledge, this is the first description of AR expression in both normal and pathological changes of the human endometrium using the RT-PCR techniques. Our observations confirmed the role of the AR in the stromal regulation of epithelial cells within the neoplastic endometrium.

Endometrial Neoplasms↗

PubMedDate not supplied

Expression and intracellular localization of Smad proteins in human endometrial cancer.

The aim of our study was to examine expression of Smad proteins i.e., Smad2, Smad3 and Smad4 both as mRNA and protein as well as their intracellular localization in normal (n=13) and neoplastic (n=42) endometrial tissue specimens using RT-PCR and immunological techniques i.e., Western blot and ELISA. Two uncommon female genital tract tumours, rhabdomyosarcoma of uterine of the cervix and uterine carcinosarcoma were also included. No statistically significant differences were found in the mRNA level of the examined Smad proteins between normal and tumour tissue specimens. Smad2 and Smad3 mRNAs were detected both in uterine carcinosarcoma and rhabdomyosarcoma of the uterine cervix. However, significantly lower Smad2 and Smad4 mRNA level was noted when the depth of myometrial invasion was considered (p<0.05). In endometrial cancer as compared to normal endometrium significantly higher levels of Smad2 and Smad3 proteins, both in cytoplasmic (p=0.002; p=0.0001) and nuclear (p=0.016; p=0.0004) fractions were observed. Both in uterine carcinosarcoma and rhabdomyosarcoma of the uterine cervix Smad2, Smad3 and Smad4 proteins were not detected. Moreover, significantly elevated Smad4 protein level in cytoplasmic fraction was stated when tumour grade and depth of myometrial invasion was undertaken (p<0.05). When intracellular distribution of Smads was considered differences between cytoplasmic and nuclear localization in normal and carcinomatous endometrium was stated. In endometrial cancer decreased number of cases with Smad3 and increased number of cases with Smad4 located in nuclear fraction was found. In conclusion, the disturbances in Smad protein expression and/or differences in their intracellular distribution suggest, that TGF-beta signaling pathway via Smads may be deregulated in endometrial carcinomas.

Blotting, Western↗