The Co-Expression of Estrogen Receptors ERα, ERß, and GPER in Endometrial Cancer.

Estrogens have important roles in endometrial cancer (EC) and exert biological effects through the classical estrogen receptors (ERs) ERα and ERß, and the G-protein-coupled ER, GPER. So far, the co-expression of these three types of ERs has not been studied in EC. We investigated ERα, ERß, GPER mRNA and protein levels, and their intracellular protein distributions in EC tissue and in adjacent control endometrial tissue. Compared to control endometrial tissue, immunoreactivity for ERα in EC tissue was weaker for nuclei with minor, but unchanged, cytoplasmic staining; mRNA and protein levels showed decreased patterns for ERα in EC tissue. For ERß, across both tissue types, the immunoreactivity was unchanged for nuclei and cytoplasm, although EC tissues again showed lower mRNA and protein levels compared to adjacent control endometrial tissue. The immunoreactivity of GPER as well as mRNA levels of GPER were unchanged across cancer and control endometrial tissues, while protein levels were lower in EC tissue. Statistically significant correlations of estrogen receptor α (ESR1) versus estrogen receptor ß (ESR2) and GPER variant 3,4 versus ESR1 and ESR2 was seen at the mRNA level. At the protein level studied with Western blotting, there was significant correlation of ERα versus GPER, and ERß versus GPER. While in clinical practice the expression of ERα is routinely tested in EC tissue, ERß and GPER need to be further studied to examine their potential as prognostic markers, provided that specific and validated antibodies are available.

Quality Control in the Slovenian National Colorectal Cancer Screening Program.

OBJECTIVES: The objective of the study was to assess the impact of an internal quality indicator (QI) audit on the quality level of colonoscopies in the National Colorectal Cancer Screening Program (NCCSP). DESIGN: Sixty-eight colonoscopists from 29 endoscopic centres participated in the NCCSP from April 2009 to January 2015. Controlled QIs were the percentage of total colonoscopies, adenoma detection rate (ADR), mean adenoma per procedure (MAP), mean adenoma per positive procedure (MAP+), right-sided ADR, sessile serrated lesion (SSL) detection rate, and patient responses to post-procedural questionnaires. A group of 3 expert endoscopists from the NCCSP Council performed 91 inspections and provided education. RESULTS: A total of 891.364 (58.2%) Slovenian citizens participated in the first 3 screening rounds of the NCCSP. Among 46.552 (6%) positive individuals, 42.866 (92.1%) underwent first colonoscopies. Total colonoscopies were performed in 98% of endoscopies (p = 0.459 between cycles), mean ADR was 51.8% (p = 0.872 between cycles), mean percentage of adenoma in the right colon was 37.5% (p = 0.227 between cycles), mean MAP was 1.1 (p = 0.981 between cycles), mean MAP+ was 2.0 (p = 0.824 between cycles), and mean SSL detection rate was 3% (p < 0.001). We observed great difference in QIs between endoscopists and a significant increase in MAP, ADR in the right colon, and SSL per endoscopist during the 6-year period. Due to quality underperformance, 3 endoscopic centres (10.3%) and 13 endoscopists (19.1%) were excluded from the program. CONCLUSIONS: The success of the NCCSP is related to the quality of colonoscopies performed. To ensure the proper quality level, regular audit and permanent education are needed.

Association between polymorphisms in segregation genes BUB1B and TTK and gastric cancer risk.

BACKGROUND: Malignant transformation of normal gastric cells is a complex and multistep process, resulting in development of heterogeneous tumours. Susceptible genetic background, accumulation of genetic changes, and environmental factors play an important role in gastric carcinogenesis. Single nucleotide polymorphisms (SNPs) in mitotic segregation genes could be responsible for inducing the slow process of accumulation of genetic changes, leading to genome instability. PATIENTS AND METHODS: We performed a case-control study of polymorphisms in mitotic kinases TTK rs151658 and BUB1B rs1031963 and rs1801376 to assess their effects on gastric cancer risk. We examined the TTK abundance in gastric cancer tissues using immunoblot analysis. RESULTS: C/G genotype of rs151658 was more frequent in patients with diffuse type of gastric cancer and G/G genotype was more common in intestinal types of gastric cancers (p = 0.049). Polymorphic genotype A/A of rs1801376 was associated with higher risk for developing diffuse type of gastric cancer in female population (p = 0.007), whereas A/A frequencies were increased in male patients with subserosa tumour cell infiltration (p = 0.009). T/T genotype of rs1031963 was associated with well differentiated tumours (p = 0.035). TT+CT genotypes of rs1031963 and GG+AG genotypes of rs1801376 were significantly associated with gastric cancer risk (dominant model; OR = 2,929, 95% CI: 1.281-6.700; p = 0.017 and dominant model; OR = 0,364, 95% CI: 0.192-0.691; p = 0.003 respectively). CONCLUSIONS: Our results suggest that polymorphisms in mitotic kinases TTK and BUB1B may contribute to gastric tumorigenesis and risk of tumour development. Further investigations on large populations and populations of different ethnicity are needed to determine their clinical utility.

Two-dimensional gel electrophoresis of gastric tissue in an alkaline pH range.

2DE in combination with MS has facilitated the discovery of several proteins with altered abundance in gastric cancer. While acidic and wide pH ranges have been widely investigated, analysis in the alkaline pH range has not been specifically performed in gastric cancer to date. In the present study, we initially optimized the 2DE in alkaline pH range (pH 7-11) for gastric tissue samples. Using a modified lysis buffer, we analyzed pooled nontumor and tumor samples for proteins with altered abundance in gastric adenocarcinoma. We successfully identified 38 silver-stained spots as 24 different proteins. Four of these were chosen for investigation with immunoblotting on individual paired samples to determine whether the changes seen in 2DE represent the overall abundance of the protein or possibly only a single form. While mitochondrial trifunctional protein (MTP) subunits were decreased in 2DE gels, immunoblotting identified their overall abundance as being differently dysregulated: in the gastric tumor samples, the MTP-α subunit was decreased, and the MTP-ß subunit was increased. On the other hand, heterogenous nuclear ribonucleoprotein M and galectin-4 were increased in the gastric tumor samples in both 2DE and immunoblotting.

AKR1B1 as a Prognostic Biomarker of High-Grade Serous Ovarian Cancer.

Although aldo-keto reductases (AKRs) have been widely studied in cancer, no study to date has examined the roles of AKR family 1 members B1 (AKR1B1) and B10 (AKR1B10) in a large group of ovarian cancer patients. AKR1B1 and AKR1B10 play a significant role in inflammation and the metabolism of different chemotherapeutics as well as cell differentiation, proliferation, and apoptosis. Due to these functions, we examined the potential of AKR1B1 and AKR1B10 as tissue biomarkers. We assessed the immunohistochemical levels of AKR1B1 and AKR1B10 in tissue paraffin sections from 99 patients with high-grade serous ovarian cancer (HGSC) and compared these levels with clinicopathological characteristics, survival, and response to chemotherapy. A higher immunohistochemical AKR1B1 expression correlated with a better overall and disease-free survival of HGSC patients whereas AKR1B10 expression did not show any significant differences. A multivariant Cox analysis demonstrated that a high AKR1B1 expression was an important prognostic factor for both overall and disease-free survival. However, AKR1B1 and AKR1B10 were not associated with different responses to chemotherapy. Our data suggest that AKR1B1 is involved in the pathogenesis of HGSC and is a potential prognostic biomarker for this cancer.

The impact of 6 years of the National Colorectal Cancer Screening Program on colorectal cancer incidence and 5-year survival.

We aimed to assess the impact of the first three rounds of the National Colorectal Cancer Screening Program (NCCSP) on CRC incidence and mortality in Slovenia. In NCCSP, we use two fecal immune tests (FITs) and if test is positive patient is referred to colonoscopy. From 2009, we invite Slovenian residents aged 50-69 years, one screening round takes 2 years. The response rate was from 56.9 to 59.9%. FIT was positive in 6.0-6.2% (more in older patients and in men; P < 0.05). The adenoma detection rate was >51.3% (more in men; P < 0.01). In NCCSP, 70.3% of all cancers diagnosed were in stages I and II, while 20.7% of all CRC were found in polyps resected during colonoscopies. Patients with positive first FIT have odds ratio 2.19 [95% confidence interval (CI), 2.06-2.32] for advanced neoplasia and cancer compared to patients with two negative FITs. The incidence rate for CRC has dropped significantly after 6 years in population and in men (P < 0.01) but not in women. Five-year CRC survival was 31.3% higher if cancer was diagnosed in NCCSP (P < 0.05). After 6 years of NCCSP, the incidence rate for CRC has dropped significantly (P < 0.01). Hazard ratio for death from CRC was 3.84 higher (95% CI, 3.36-4.40; P < 0.001) in patients with cancer detected outside the program.

Sensitivity and reproducibility of conventional qualitative and quantitative PCR assays for detection of the t(14;18)(q32;q21) chromosomal translocation in biopsy material from patients with follicular lymphoma.

Follicular lymphoma (FL) is characterized by the t(14;18)(q32;q21) chromosomal translocation which can be detected by polymerase chain reaction (PCR) in approximately 70% of cases. The aim of our retrospective study was to evaluate the sensitivity and the reproducibility of both conventional qualitative and quantitative PCR assays for detection of the t(14;18)(q32;q21) chromosomal translocation in biopsy material. Fifty-seven formalin-fixed, paraffin-embedded tumor lymph node (LN) specimens from 50 patients with FL were included in the study. Qualitative PCR was performed with primer sets specific for the MBR, far3'-MBR and the mcr regions, respectively. Quantitative PCR was performed using the LightCycler instrument and the LightCycler - t(14;18) Quantification Kit (MBR). The overall detection rate of the t(14;18) in our study (52.6%) was in accordance with the literature. Of the t(14;18)-positive cases, 49.1% had breakpoints within the MBR and only 3.5% had breakpoints within the mcr. The most sensitive method was LightCycler-based PCR with a detection rate of 47.4%, followed by MBR1,2 assay (43.9%). We observed good agreement between qualitative MBR1,2 and quantitative LightCycler-based assay with a slightly higher detection rate of the quantitative method. The sensitivities of both methods were in accordance with results from other studies. Since LightCycler-based assay detects only breakpoints within the MBR, qualitative PCR should be employed in routine diagnostic settings for detection of breakpoints within the mcr and far3'-MBR regions.

Tissue microarrays for routine diagnostic assessment of HER2 status in breast carcinoma.

The use of tissue microarray (TMA) technology may substantially reduce the costs of routine testing of breast carcinomas for human epidermal growth factor receptor 2 (HER2) status. After a preliminary pilot study comparing the TMA results with those obtained on whole section, which showed an excellent agreement (with kappa values >0.90) for both immunohistochemical and fluorescent in situ hybridization (FISH) method, we introduced the TMA technique in our routine work. A total of 1158 invasive breast carcinomas were submitted for the determination of HER2 status, which was assessed in 74 weekly runs. One hundred twenty-five of 1084 surgical specimens (11.5%) were judged as unsuitable for inclusion into TMAs. In 32 of 959 tumors included in TMAs (3.3%), the respective cores were uninformative, and HER2 status was determined on whole sections. Thus, HER2 status was finally determined on TMA in 927 cases (81.1%). A typical weekly run comprised 1 TMA (consisting, on average, of 13 tumors), 2 whole sections of surgical specimens and 1 whole section of core needle biopsy, and the number of processed slides for each method decreased from 16 to 4 per week. In all, 14.7% of tumors were HER2 positive by FISH. In both TMAs and whole sections, immunohistochemical results were in good agreement with FISH for cases scored as 0/1+ (98% and 97%) and for those scored as 3+ (96% and 87%), whereas concordance was poor in cases scored as 2+ (30% and 13%, respectively).

Proteomic analysis of gastric cancer and immunoblot validation of potential biomarkers.

AIM: To search for and validate differentially expressed proteins in patients with gastric adenocarcinoma. METHODS: We used two-dimensional gel electrophoresis and mass spectrometry to search for differentially expressed proteins in patients with gastric adenocarcinoma. A set of proteins was validated with immunoblotting. RESULTS: We identified 30 different proteins involved in various biological processes: metabolism, development, death, response to stress, cell cycle, cell communication, transport, and cell motility. Eight proteins were chosen for further validation by immunoblotting. Our results show that gastrokine-1, 39S ribosomal protein L12 (mitochondrial precursor), plasma cell-induced resident endoplasmic reticulum protein, and glutathione S-transferase mu 3 were significantly underexpressed in gastric adenocarcinoma relative to adjacent non-tumor tissue samples. On the other hand, septin-2, ubiquitin-conjugating enzyme E2 N, and transaldolase were significantly overexpressed. Translationally controlled tumor protein was shown to be differentially expressed only in patients with cancer of the gastric cardia/esophageal border. CONCLUSION: This work presents a set of possible diagnostic biomarkers, validated for the first time. It might contribute to the efforts of understanding gastric cancer carcinogenesis.