A Diketopyrrolopyrrole-Based Dimer as a Blue Pigment.

1,4-Diketopyrrolo[3,4-c]pyrroles (DPPs) constitute a class of hydrogen-bonded pigments covering a color range from yellow-orange to dark violet. We report facile dimerization of a Boc-substituted 3,6-dithienyl-DPP. The formed dimer shows brilliantly blue color as a result of the expansion of the chromophore. The soluble dimer acts as latent pigment and is converted to the corresponding pigment either via thermocleavage or acidic deprotection of the Boc groups. The synthesized pigment is characterized by high migrational stability in a polymer matrix and a clear blue color.

Effect of fluorination of naphthalene diimide-benzothiadiazole copolymers on ambipolar behavior in field-effect transistors.

Two naphthalene diimide (NDI)-benzothiadiazole (BT) based conjugated polymers with high molecular weight, P1 and P2, were synthesized by introducing F atoms to modulate the electron-donating ability of the BT moiety. 3-Decyl-pentadecyl branched alkyl side chains were employed and expected to improve the molecular organization and device performance. Both polymers have excellent solubility in common organic solvents. UV-vis-NIR absorption and cyclic voltammetry indicate that the maximum absorption wavelength of P2 is blue-shifted and the HOMO energy level of P2 is decreased in comparison with P1. Two dimensional wide angle X-ray scattering of thin films revealed a similar organization of both polymers. A less balanced transport in field-effect transistors with increased electron mobility of 0.258 cm2 V-1 s-1 and lowered hole transport of 2.4 × 10-3 cm2 V-1 s-1 was found for P2. Polymer devices of P1 exhibited a balanced ambipolar transport, with a hole mobility of 0.073 cm2 V-1 s-1 and electron mobility of 0.086 cm2 V-1 s-1.

Metallothionein 2A genetic polymorphisms and risk of ductal breast cancer.

Metallothioneins (MTs) are a family of metal binding proteins that play an important role in cellular processes such as proliferation and apoptosis. Metallothionein 2A is the most expressed MT isoform in the breast cells. A number of studies have demonstrated increased MT2A expression in various human tumors, including breast cancer. We carried out an association study to examine whether MT2A gene polymorphisms are associated with risk of breast cancer. Information on lifestyle risk factors was collected via a self-administered questionnaire. Genotyping was conducted using polymerase chain reaction-restriction fragment length polymorphism technique. Three single nucleotide polymorphisms (SNP) rs28366003, rs1610216 and rs10636 were genotyped in 534 breast cancer cases and 556 population controls. One SNP in MT2A (rs28366003) showed a positive association with breast cancer. Compared with homozygous common allele carriers, heterozygous for the G variant [odds ratio (OR) = 1.92, 95 % confidence interval (CI):1.28-2.81, p trend <0.01; the OR assuming a dominant model 1.93 (95 % CI: 1.29-2.89, (p dominant) <0.02) after adjustment for age, family history, smoking status, BMI, menarche, parity, menopausal status and use of contraceptive and menopausal hormones] had a significantly increased risk of breast cancer in Polish population, as well as women with haplotypes, including variant allele of rs28366003 SNP (OR = 1.58, CI: 0.41-6.33, p global = 0.03). Our data suggest that the rs28366003 SNP in MT2A is associated with risk of breast cancer in Polish population.

RAD51 genotype and triple-negative breast cancer (TNBC) risk in Polish women.

The most lethal damage for the cell among all damage is double-strand breaks (DSB) of DNA. DSB cause development of cancer diseases including the triple-negative molecular subtype of breast cancer. The aim of this work was to evaluate the single nucleotide polymorphism -135G>C (rs1801320) of the RAD51 gene encoding DNA repair proteins by homologous recombination (HR) in triple-negative breast cancer (TNBC). We assessed the RAD51 -135G>C polymorphism in 50 women with triple-negative breast cancer and in 50 women from the control group. RAD51 polymorphism was analysed by the PCR-RFLP (restriction fragment length polymorphism) technique. Our results demonstrated a significant positive association between the RAD51 C/C genotype and TNBC, with an adjusted odds ratio (OR) of 5.95 (p = 0.002). The homozygous C/C genotype was found in 68% of breast cancer cases and 20% of controls. The variant 135C allele of RAD51 increased TNBC risk. This is the first study linking single nucleotide polymorphisms of the RAD51 gene with TNBC incidence in the population of Polish women. In conclusion, RAD51 polymorphisms may be regarded as predictive factors of triple-negative breast cancer in the female population. Large studies are needed to confirm our findings.

Amplification of Her-2/neu oncogene in GERD - Barrett's metaplasia ­ dysplasia - adenocarcinoma sequence.

BACKGROUND/AIMS: Esophageal adenocarcinoma (ADC) incidence has been increasing dramatically in the past 3 decades despite the surveillance programs in patients with Barrett's esophagus (BE). Therefore, markers of early neoplastic progression are required to predict of cancer risk in BE patients. The aim of this study was to investigate the frequency of Her2/neu amplification in different stages during Barrett's-related carcinogenesis. METHODOLOGY: Her2/neu amplification analysis in 39 patients with gastroesophageal reflux disease (GERD), in 34 with BE, in 11 with dysplasia and 13 with ADC were performed with PCR. RESULTS: Her2/neu amplification was detected in 8% (3/39) GERD patients, 15% (5/34) with BE, 41% (7/17) with dysplasia and in 54% (7/13) with ADC. We observed an increasing trend in the frequency of Her2/neu alteration between BE-carcinogenesis stages (p=0.001). This finding was confirmed in the logistic regression analysis showing gradient in odds ratios between BE (2.07; 95% CI: 0.46-9.39), dysplasia (8.4; 95% CI: 1-83-38.53) and ADC (14.0; 95% CI: 2.81-69.69) compared to GERD; it was even higher after adjustment for age and gender. CONCLUSIONS: Her2/neu alterations may occur early and increasingly during Barrett's malignant progression. We suggest that it may be useful to stratify the risk of adenocarcinoma in patients with Barrett's esophagus.

Association between the c.*229C>T polymorphism of the topoisomerase IIß binding protein 1 (TopBP1) gene and breast cancer.

Topoisomerase IIß binding protein 1 (TopBP1) is involved in cell survival, DNA replication, DNA damage repair and cell cycle checkpoint control. The biological function of TopBP1 and its close relation with BRCA1 prompted us to investigate whether alterations in the TopBP1 gene can influence the risk of breast cancer. The aim of this study was to examine the association between five polymorphisms (rs185903567, rs116645643, rs115160714, rs116195487, and rs112843513) located in the 3'UTR region of the TopBP1 gene and breast cancer risk as well as allele-specific gene expression. Five hundred thirty-four breast cancer patients and 556 population controls were genotyped for these SNPs. Allele-specific TopBP1 mRNA and protein expressions were determined by using real time PCR and western blotting methods, respectively. Only one SNP (rs115160714) showed an association with breast cancer. Compared to homozygous common allele carriers, heterozygous and homozygous for the T variant had significantly increased risk of breast cancer (adjusted odds ratio = 3.81, 95% confidence interval: 1.63-8.34, p = 0.001). Mean TopBP1 mRNA and protein expression were higher in the individuals with the CT or TT genotype. There was a significant association between the rs115160714 and tumor grade and stage. Most carriers of minor allele had a high grade (G3) tumors classified as T2-T4N1M0. Our study raises a possibility that a genetic variation of TopBP1 may be implicated in the etiology of breast cancer.

RAD51 gene polymorphisms and sporadic colorectal cancer risk in Poland.

BACKGROUND: DNA repair processes play an important role in protection against carcinogenic factors. Mutations in DNA repair genes, which code proteins engaged in repair processes, may lead to carcinogenesis and among others also to colorectal cancer (CRC) development. The genetic variability in RAD51 may contribute to the appearance and progression of various cancers including CRC. The aim of the study was to compare the distribution of genotypes of RAD51 135G>C and 172G>T polymorphism between colorectal cancer patients and controls. MATERIAL AND METHODS: Both polymorphisms were evaluated by PCR-RFLP methods in colorectal tissue of 320 colorectal cancer subjects and 320 healthy subjects who served as controls. RESULTS: In the present work we demonstrated a significant positive association between the RAD51 C/C genotype and colorectal carcinoma. Variant 135C allele of RAD51 increased the cancer risk. However, we did not observe any relationship between each polymorphism and colorectal cancer progression assessed by node metastasis, tumour size and Dukes' stage. CONCLUSIONS: Our results suggest that variant genotypes of the 135G>C of RAD51 polymorphism may be positively associated with colorectal carcinoma in the Polish population. Further studies conducted on a larger group are required to clarify this point.

Single nucleotide polymorphism (SNP) Thr241Met in the XRCC3 gene and breast cancer risk in Polish women.

BACKGROUND: Single nucleotide polymorphisms (SNPs) in DNA repair genes may be associated with differences in the repair efficiency of DNA damage and may influence an individual's risk of cancer. The XRCC3 protein plays a critical role in Homologous Recombination Repair (HRR) accounting for repair of DNA double-strand breaks (DSB). AIM: The aim of the present study was to evaluate associations between the risk of breast cancer and Thr241Met polymorphism in the XRCC3 gene. MATERIAL AND METHODS: Single nucleotide polymorphism was genotyped by the PCR-RFLP (restriction fragment-length polymorphism) method in 760 women with sporadic breast cancer and in 760 control samples. The present study confirmed a relationship between XRCC3 Thr241Met polymorphism and breast cancer progression, assessed by the degree of lymph node metastases and histological stages. CONCLUSION: Our findings suggest that the analysis of XRCC3 polymorphism, may contribute to better understanding of the mechanisms of breast cancer by evaluating possible interactions between these genotypes and well-established risk factors for breast cancer.

Expression of TopBP1 in hereditary breast cancer.

TopBP1 protein displays structural as well as functional similarities to BRCA1 and is involved in DNA replication, DNA damage checkpoint response and transcriptional regulation. Aberrant expression of TopBP1 may lead to genomic instability and can have pathological consequences. In this study we aimed to investigate expression of TopBP1 gene at mRNA and protein level in hereditary breast cancer. Real-time quantitative PCR was performed in 127 breast cancer samples. Expression of TopBP1 mRNA in lobular carcinoma was significantly lower compared with ductal carcinoma (p < 0.05). The level of TopBP1 mRNA appeared to be lower in poorly differentiated (III grade) hereditary breast cancer in comparison with moderately (II grade) and well-differentiated cancer (I grade) (p < 0.05 and p < 0.001 respectively). We analyzed TopBP1 protein expression using immunohistochemistry and Western blot techniques. Expression of TopBP1 protein was found to be significantly increased in poorly differentiated breast cancer (III grade) (p < 0.05). The percentage of samples with cytoplasmic apart from nuclear staining increased with increasing histological grade. There was no significant association between level and intracellular localization of TopBP1 protein in hereditary breast cancer and other clinicopathological parameters such as estrogen and progesterone receptors status, appearance of metastasis in the axillary lymph nodes and type of cancer. Our data suggest that decreased level of TopBP1 mRNA and increased level of TopBP1 protein might be associated with progression of hereditary breast cancer.

Single nucleotide polymorphisms of RAD51 G135C, XRCC2 Arg188His and XRCC3 Thr241Met homologous recombination repair genes and the risk of sporadic endometrial cancer in Polish women.

BACKGROUND: The genes RAD51, XRCC2 and XRCC3 encode proteins that are important for the repair of double-strand DNA breaks by homologous recombination. Therefore, genetic variability in these genes may contribute to the occurrence and progression of endometrial cancer. METHODS: The subject of investigation in the reported study was the distribution of genotypes and the prevalence of alleles of the RAD51 G135C, XRCC2 Arg188His and XRCC3 Thr241Met polymorphism in 230 cases of sporadic endometrial cancer; the polymorphisms were determined by polymerase chain reaction-restriction fragment-length polymorphism methods. RESULTS: The obtained results demonstrated a significant positive association between the RAD51 C/C genotype and endometrial carcinoma, with an adjusted odds ratio (OR) of 3.75 (P < 0.0001). The homozygous C/C genotype was found in 72% of endometrial cancer cases and in 19% of the used controls. The variant 135C allele of RAD51 increased the cancer risk (OR = 1.64 [1.28-2.10]P < 0.0001). There were no significant differences between the distribution of G135C, Arg188His and Thr241Met genotypes in the subgroups assigned to histological grades. CONCLUSIONS: The obtained results indicate that the polymorphism of RAD51, but not of either XRCC2 or XRCC3 genes, may be positively associated with the incidence of endometrial carcinoma in the population of Polish women. Further studies, including those on a larger group of patients, are required to further clarify this point.

Polymorphism of the DNA repair genes RAD51 and XRCC2 in smoking- and drinking-related laryngeal cancer in a Polish population.

INTRODUCTION: Cigarette smoke and alcohol can generate reactive oxygen species, which may induce DNA double-strand breaks (DSBs), the most serious DNA lesion. In humans, DSBs are repaired mainly by non-homologous end joining and homologous recombination repair (HRR). Several polymorphisms in the DNA repair gene have been extensively studied in the association with various human cancers. In the present work we investigated the association between polymorphisms of two HRR genes, XRCC2 and RAD51, and tobacco- and alcohol-related larynx cancer in a Polish population. MATERIAL AND METHODS: Two polymorphisms of the XRCC2 gene, -41657C > T (rs718282) and 31479G > A (rs3218536), as well as one polymorphism of the RAD51 gene, -135G > C (rs1801320), were investigated by PCR-RFLP in 253 patients with larynx cancer and 253 age- and sex-matched non-cancer controls. RESULTS: Analysis of the gene-smoking and -drinking interactions revealed a weak association between larynx cancer and the -41657C > T polymorphisms of the XRCC2 gene among the moderate alcohol drinkers. The C allele of the -135G > C polymorphism of RAD51 increased cancer risk in the smoker group. Increased risk was also found for heavy drinkers. Additionally, there were no significant differences between distributions of genotypes in subgroups assigned to different TNM stages and grades. CONCLUSIONS: The results indicated that the -135G > C polymorphism of the RAD51 gene may be associated with smoking- and drinking-related larynx cancer in Poland.

Role of cyclooxygenase-2 gene polymorphisms in pancreatic carcinogenesis.

AIM: To evaluate the clinical significance of -765G/C and -1195G/A cyclooxygenase-2 (COX-2) gene polymorphisms in patients with pancreatic cancer (PC). METHODS: The study included 201 patients: 85 with PC and 116 healthy controls. -765G/C and -1195G/A COX-2 gene polymorphisms were studied in DNA isolated from blood samples. The associations of the analyzed genotypes and clinical data at diagnosis were evaluated. RESULTS: We found an increased frequency of the homozygous -1195AA COX-2 genotype in patients with PC (53.7%) compared with the control group (21%) (P < 0.01). In contrast, the distribution of genotype and allele frequencies of the -765G/C COX-2 polymorphism in the PC patients were not different from those in control groups. A correlation between presence of homozygous -1195AA COX-2 genotype and tumor size > 3 cm was observed (P < 0.05). Analyzed polymorphisms were unrelated to the patients' sex and age, nor to the presence of regional or distant metastases. CONCLUSION: These preliminary results indicate that the -1195G/A COX-2 polymorphism may play an important role in PC prognosis and carcinogenesis.

135G>C and 172G>T polymorphism in the 5' untranslated region of RAD51 and sporadic endometrial cancer risk in Polish women.

BACKGROUND: Despite advanced diagnostic and therapeutic procedures, endometrial cancer (EC) is still responsible for high morbidity and mortality of women. The genetic variability in RAD51 may contribute to the appearance and progression of various cancers including EC. AIM: We investigated the association of polymorphisms in the DNA repair genes RAD51 135G>C and 172G>T with endometrial cancer risk. MATERIAL AND METHODS: The genotypes of RAD51 135G>C and 172G>T polymorphism were determined by PCR-RFLP methods in endometrial tissue of 240 cancer subjects and 240 healthy subjects who served as controls. RESULTS: In the present work we demonstrated a significant positive association between the RAD51 C/C genotype and endometrial carcinoma, with an adjusted odds ratio (OR) of 13.0 (p < 0.0001). The distribution of genotypes for 135G>C SNP in endometrial cancer patients vs. controls was: 10% vs. 27% for GG, 13% vs. 58% for GC and 77% vs. 15% for CC genotype, respectively. Variant 135C allele of RAD51 increased the cancer risk (OR = 1.81; 95% CI 0.11-2.93, p = 0.022). The higher risk of EC occurrence was associated with the combined C135C-G172T genotype (OR = 7.69; 95% CI 3.45-17.12). CONCLUSION: The results indicated that the polymorphism 135G>C of the RAD51 gene may be positively associated with endometrial carcinoma in the Polish population. Further studies, conducted on a larger group, are required to clarify this point.

Single nucleotide polymorphism in DNA base excision repair genes XRCC1 and hOGG1 and the risk of endometrial carcinoma in the Polish population.

BACKGROUND: Polymorphisms in the human oxoguanine glycosylase 1 ( hOGG1 ) and X-ray repair cross-complementing 1 ( XRCC1 ) genes have been extensively studied in the association with various human cancers such as endometrial cancer. MATERIAL AND METHODS: The genotype analysis of hOGG1 Ser326Cys and XRCC1 Arg399Gln gene polymorphisms for 150 endometrial cancer patients and 150 controls of cancer-free subjects, in the Polish population, were performed using PCR-based restriction fragment length polymorphism (PCR-RFLP). RESULTS: Although there were no significant (p > 0.05) differences in the frequencies of genotypes or alleles of hOGG1 genes between patients and controls, the frequency of the XRCC1 399Gln allele was significantly greater in endometrial cancer patients compared with controls (p = 0.033) with an odds ratio of 1.39 (95% confidence interval 0.99 to 1.95). The distributions of genotypes and alleles of the genes hOGG1 and XRCC1 were not significantly associated with different grades of endometrial cancer (p > 0.05). CONCLUSION: In conclusion, these findings indicated that XRCC1 Arg399Gln polymorphism may be a genetic determinant for developing endometrial cancer. The hOGG1 Ser326Cys may not play an important role in susceptibility to endometrial cancer in Polish women.

Single nucleotide polymorphisms in the homologous recombination repair genes and breast cancer risk in Polish women.

Genetic polymorphisms in homologous recombination repair genes that can lead to protein haploinsufficiency are generally associated with increased cancer risk. The aim of the present study was to evaluate associations between the risk of breast cancer and single nucleotide polymorphisms in the genes, encoding three key proteins of the homologous recombination repair: RAD51 (the human homologue of the E. coli RecA protein), X-ray repair cross-complementing group (XRCC) 2 and XRCC3. The polymorphisms studied were G135C of the RAD51 gene (c. -98 G>C; rs1801320), Arg188His of the XRCC2 gene (c. 563 G>A; rs3218536), and Thr241Met of the XRCC3 gene (c. 722 C>T; rs861539). Each polymorphism was genotyped by the PCR-RFLP (restriction fragment-length polymorphism) method in 700 Polish female patients with sporadic breast cancer and in 708 cancer-free women, who served as controls. In the present study, we showed the association between RAD51 G135C polymorphism and the incidence of breast cancer (p < 0.0001), but found no significant association with XRCC2 Arg188His or XRCC3 Thr241Met polymorphism. Instead, significant association was identified between XRCC2 Arg188His or XRCC3 Thr241Met polymorphism and breast cancer progression, assessed by the histological grading. However, each of these three polymorphisms was not associated with the tumor size or the lymph node metastases. This study provides evidence that links single nucleotide polymorphisms of RAD51 and XRCC2/3 genes with the risk of breast cancer in Polish women. In conclusion, RAD51 G135C, XRCC2 Arg188His and XRCC3 Thr241Met polymorphisms may be regarded as predictive factors of sporadic breast cancer in female population.

The prevalence of cationic trypsinogen (PRSS1) and serine protease inhibitor, Kazal type 1 (SPINK1) gene mutations in Polish patients with alcoholic and idiopathic chronic pancreatitis.

BACKGROUND: The main cause of chronic pancreatitis (CP) is excessive alcohol consumption. On the other hand, only 5-10% of heavy drinkers develop chronic pancreatitis. We have only limited information regarding the pathogenic mechanism by which alcohol leads to the disease. Mutations of the PRSS1 and SPINK 1 have been mostly implicated in hereditary and idiopathic CP, but their presence in other types of this disease have also been reported. AIMS: The aim of the study was to determine the frequency of PRSS1 and SPINK1 mutations in patients with chronic alcoholic (ACP) and idiopathic pancreatitis (ICP) as well as to investigate their relation to the clinical course of the disease. METHODS: The study included 33 ACP and 14 ICP patients as well 46 healthy subjects. The diagnosis of CP was based on clinical data, ultrasound, and computed tomography. After isolation of DNA from peripheral blood two trypsinogen mutations were detected N29I and R122H by allelo-specific amplification polymerase chain reaction (ASA-PCR) and by the PCR-restriction fragment length polymorphism (RFLP). Beside this N34S mutation of SPINK1 was analyzed by PCR restriction fragment length polymorphism (PCR-RFLP). RESULTS: PRSS1 mutations have been detected in 11 (33%) patients with ACP. The frequency of the PRSS1 mutations was higher in patients with ACP than in controls (4.3%) (p < 0.001). The frequency of PRSS1 mutation was present in 21.4% of ICP patients, which was significantly higher (p < 0.05) than in controls. Overall, six (18%) SPINK1 mutations in ACP group have been detected. Among 14 patients with ICP, in four (28.6%) of them SPINK1 has been detected. The same mutations have also been found in three (6.5%) control subjects. The frequency of the N34S mutation was higher in patients with ICP than in the controls (p < 0.05), but the frequency of N34S mutation did not differ between ACP and the control group. No relations have been detected between PRSS1 and SPINK1 mutations presence and clinical course and complications of CP. CONCLUSIONS: Those preliminary data suggest the high prevalence of SPINK1 and PRSS1 mutations in the Polish population, generally, as well as in CP patients. It may be speculated that those mutations contribute to the development of chronic pancreatitis, especially in patients with alcohol overindulgence.

Concentration of cadmium, nickel and aluminium in female breast cancer.

AIMS: The aim of this study was to investigate the cadmium (Cd), nickel (Ni) and aluminium (Al) concentrations in female breast cancer and normal tissue. MATERIALS AND METHODS: The concentration of metals in 16 non-cancerous breast tissues and 67 breast cancer samples was measured by flame atomic absorption spectrometry. RESULTS: In the case of normal breast tissue the concentrations were 0.61 ± 0.24 µg Cd/g dry tissue, 1.84 ± 0.67 µg Ni/g dry tissue, and 3.63 ± 1.00 µg Al/g dry tissue, whereas in breast cancer concentrations of metals were 0.76 ± 0.38 µg/g dry tissue, 2.26 ± 0.79 µg/g dry tissue, and 4.40 ± 1.82 µg/g dry tissue, respectively. The concentration of Cd and Al in normal breast tissue was significantly lower than in breast cancer. In the case of Ni concentration, we did not observe statistically significant differences between normal and cancerous tissue. There were no significant differences in concentration of studied metals, in breast cancer, in the context of age, menopausal status, and cancer histological grading. CONCLUSION: The data obtained show higher concentration of cadmium and aluminium and support a possible relationship between those metals and breast cancer.

XRCC1 and XRCC3 DNA repair gene polymorphisms in breast cancer women from the Lodz region of Poland.

AIM: Genetic polymorphism in XRCC1 and XRCC3 genes may influence DNA repair capacity and, in turn, confer predisposition to breast cancer. MATERIAL AND METHODS: In the present work the distribution of genotypes and frequency of alleles of the Arg194Trp and Arg399Gln polymorphism of XRCC1 and Trp241 Met polymorphism in XRCC3 in breast cancer women were analysed. Blood samples were obtained from 150 women with breast cancer and controls (n = 106). The polymorphisms were determined by PCR-RFLP methods. RESULTS: No association between XRCC1 Arg399Gln and Arg194Trp genotype and breast cancer risk was observed. The distribution of the genotypes of the Trp241 Met polymorphism of XRCC3 in both controls and patients did not differ significantly (p > 0.05) from those predicted by the Hardy-Weinberg distribution. There were no significant differences (p > 0.05) in genotype distributions and allele frequencies between subgroups assigned to histological stage. CONCLUSION: The results suggest that the Arg194Trp and Arg399Gln polymorphism of the XRCC1 gene as well as Trp241 Met polymorphism in XRCC3 may not be linked with appearance and development of breast cancer.

Expression of estrogen and progesterone receptor genes in endometrium, myometrium and vagina of postmenopausal women treated with estriol.

CONTEXT AND OBJECTIVE: Estriol is an estrogen with considerably weaker stimulatory effects on endometrial proliferation than estradiol. A study was conducted to determine the level of estrogen receptors (ERs) and progesterone receptors (PRs) in women who received 14-day vaginal estriol therapy, compared with those who did not receive this therapy. ER and PR gene expression was analyzed in the endometrium, myometrium and vagina of postmenopausal women treated with estriol. DESIGN AND SETTING: Analytical cross-sectional study, at the Research Institute of the Polish Mothers' Memorial Hospital, Lodz, Poland. METHODS: Twenty-seven postmenopausal women (57-74 years of age) were included in the study. All of them were waiting for per vaginam hysterectomy or plastic surgery on the vagina and perineum because of uterine prolapse. ER and PR gene expression was determined by means of the technique of reverse transcription polymerase chain reaction (RT-PCR). RESULTS: In the estriol-treated patients, in comparison with the control group, a significant increase in ER gene expression was observed in the endometrium and vagina, while enhanced PR gene expression was found in the endometrium. However, under histological examination of the endometrium, estrogen stimulation of low and medium degree was diagnosed for 21.4% and 14.3% of the estriol-treated women, respectively. CONCLUSION: The results obtained suggest that the women who received 14 days of treatment with vaginal estriol had higher ER and PR mRNA levels. No difference between these groups regarding endometrial proliferation was observed.