Assessment of the diagnostic usefulness of liquid-based cytology. The impact of modifications.

The technique of liquid-based cytology (LBC) is of increasing diagnostic value in non-gynecological cytology. The purpose of the present study was to validate modifications to stages of the LBC process and to assess the diagnostic usefulness of the LBC technique. Between May 2021 and January 2022, a total of 484 samples were prepared from routine cytology tests carried out in the Department of Tumor Pathology of The Greater Poland Cancer Center. The material was obtained from fine-needle aspiration biopsies and fluid samples. One hundred cases were selected for the research described in the article. The slides were prepared using the Becton Dickinson Totalys SlidePrep device. Based on the research, it was concluded that predominantly the LBC technique gives better results than a conventional smear because the background, which would otherwise make it difficult to assess preparations, was eliminated. Additionally, in LBC preparations the cellularity was increased, and the cells were arranged in a monolayer system, which improves the image quality. The introduction of modifications to the LBC method facilitated the process of sample preparation, without adversely affecting the quality of the obtained material.

Potential impact of HercepTest™ mAb PharmDx (Dako Omnis) (ge001) in breast cancer diagnosis.

The HER2 gene is a biomarker for breast cancer prognosis and treatment. Overexpression of HER2 protein determined by immunohistochemistry (IHC) or amplification of the HER2 gene determined by fluorescence in situ hybridization (FISH) is a condition for qualifying patients for anti-HER2 therapy. Due to the high toxicity of anti-HER2 treatment, proper patient selection is essential. In our study we compared 40 cases with IHC staining of HER2 antibody determined by Ventana PATHWAY anti-HER2/neu antibody (4B5) as HER2 2+ with the new antibody (HercepTest™ mAb PharmDx [Dako Omnis] [GE001]). Then using a double-blind study we compared the (IHC) evaluation with FISH results. In 65% of cases (26/40) the IHC 2+ score remained unchanged, in 32.5% of cases (13/40) expression of HER2 protein after IHC with new antibody was indicated as 3+ score, and in one case we observed a decrease of HER2 protein expression to 1+. In all cases but one, in which we found IHC HER 3+ with new antibody, there was FISH amplification. We have reason to believe that the new antibody will reduce the diagnostic time and avoid unnecessary costs. Due to the small study group, further investigation is needed.

The utility of 18F-FDG PET/CT in brain tumours diagnosis.

Background: The purpose of the study was to discuss whether 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) study protocol should include brain imaging. Materials and methods: Analysis of international societies recommendations compared with the original data obtained in over 1000 consecutive torso and brain 18F-FDG PET/CT studies collected in 2010. Results: According to the international societies recommendations, the 18F-FDG should not be the radiotracer of choice considering the brain region PET/CT study. However, it can be performed as an additional brain imaging tool. Based on at least a 3-year follow-up, we detected 8 cases of suspicious brain findings and no primary lesion among over 1000 consecutive torso and brain 18F-FDG PET/CT scans performed in 2010. However, in 5 out of 8 patients, the brain lesion was the only metastasis detected, affecting further therapy. Conclusions: The 18F-FDG PET/CT study may help detect malignant brain lesions and, therefore, including brain region imaging into the study protocol should be considered.

Iris melanoma with ciliary body infiltration presenting as a presumed chronic unilateral inflammatory glaucoma. The challenges of iris tumor biopsy assessment.

Uveal melanoma is the most common primary malignancy of the eye in adults. It may involve the choroid and ciliary body, and in only 2-3% of cases it involves the iris. We present a case of a 56-year-old patient with a 6-year history of unilateral, inflammatory, refractory glaucoma of the right eye. Due to acquired heterochromia and heterogeneous thickness of the iris, iris melanoma was suspected, but the incisional biopsy did not confirm the diagnosis. In the next months, the lesion enlarged and the eye globe was enucleated. Histopathological examination revealed an iridociliary melanoma with annular growth pattern.

The prevalence of various eyelid skin lesions in a single-centre observation study.

INTRODUCTION: The role of the eyelids is to protect and moisturise the eye. Despite its small relative surface area, 5-10% of skin cancers originate in the eyelids. AIM: To assess the prevalence of different types of skin lesions in the area of eyelids based on retrospective histopathology data from a tertiary centre. MATERIAL AND METHODS: Among 544 included eyelid lesions, 429 (79%) were benign and 115 (21%) were malignant. In the benign group, the most common finding was a chalazion (49.2%) followed by squamous papilloma (22.8%), seborrheic keratitis (10%), epidermal cyst (8.2%), and intradermal nevus (5.1%). Out of all malignant lesions, the most common diagnosis was basal cell carcinoma (BCC) in 110 (95.7%) patients. RESULTS: Squamous cell carcinoma (SCC) was diagnosed in 3 (2.6%) patients and sebaceous gland carcinoma (SGC) in 2 (1.7%). No malignant melanoma was identified in the studied group. CONCLUSIONS: Although benign lesions are the most common eyelid tumours, it is essential to differentiate between benign and malignant eyelid tumours because early detection and appropriate treatment may improve the cosmetic effect and reduce recurrences.

Evaluation of physiologic and abnormal glucose uptake in palatine tonsils: differential diagnostics with sequential dual-time-point 2-deoxy-2-[18F]FDG PET/CT.

BACKGROUND: The aim of this article was to evaluate the usefulness of sequential dual-time-point 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (DTP [18F]FDG PET/CT) in distinguishing physiologic, inflammatory and malignant palatine tonsils as difficult to differentiate in the oncological practice. METHODS: A total of 90 patients before the treatment underwent sequential DTP [18F]FDG PET/CT examinations. We analyzed 104 structures in 90 patients: 31 physiologic tonsils, 28 histopathologically confirmed inflammatory tonsils of non-specified origin, 31 histopathologically confirmed palatine tonsils cancer and 14 non-malignant contralateral tonsils in patients with histopathologically confirmed unilateral palatine tonsil malignancy. Patients underwent sequential [18F]FDG PET/CT examinations at 60 and 90 minutes post-injection of the [18F]FDG. We analyzed the SUVmax and SUVmean values at 60 and 90 minutes post-injection changes over time and the Retention Index (RI-SUVmax). To find the predictive SUV value and the RI cut-off between physiology, inflammatory and malignancy, we used the ROC analysis. RESULTS: The average SUVmax values at 60 and 90minutes post-injection within physiologic palatine tonsils were 1.36±0.26 and 1.31±0.26, respectively, P>0.05. The average SUVmax values at 60 and 90 minutes post-injection within inflammatory and malignant tonsils were 3.74±1.45, 3.80±1.47 (P>0.05) and 5.19±2.19, 5.81±2.50 (P<0.05), respectively. The RI-SUVmax fluctuation over time were 5±28% within physiologic, -4±11% within contralateral non-malignant tonsils in patients with one tonsil involved, 2±11% within inflammatory and 13±13% within malignant tonsils. CONCLUSIONS: The sequential dual-time-point [18F]FDG PET/CT examinations may increase the sensitivity and the specificity of the PET/CT method in differential palatine tonsils diagnosis.

Functionalized silk spheres selectively and effectively deliver a cytotoxic drug to targeted cancer cells in vivo.

BACKGROUND: Chemotherapy is often a first-line therapeutic approach for the treatment of a wide variety of cancers. Targeted drug delivery systems (DDSs) can potentially resolve the problem of chemotherapeutic drug off-targeting effects. Herein, we examined in vivo models to determine the efficacy of Her2-targeting silk spheres (H2.1MS1) as DDSs for delivering doxorubicin (Dox) to Her2-positive and Her2-negative primary and metastatic mouse breast cancers. RESULTS: The specific accumulation of H2.1MS1 spheres was demonstrated at the site of Her2-positive cancer. Dox delivered only by functionalized H2.1MS1 particles selectively inhibited Her2-positive cancer growth in primary and metastatic models. Moreover, the significant effect of the Dox dose and the frequency of treatment administration on the therapeutic efficacy was indicated. Although the control MS1 spheres accumulated in the lungs in Her2-positive metastatic breast cancer, the Dox-loaded MS1 particles did not treat cancer. Histopathological examination revealed no systemic toxicity after multiple administrations and at increased doses of Dox-loaded silk spheres. Although the studies were performed in immunocompetent mice, the H2.1MS1 silk spheres efficiently delivered the drug, which exerted a therapeutic effect. CONCLUSION: Our results indicated that functionalized silk spheres that enable cell-specific recognition, cellular internalization, and drug release represent an efficient strategy for cancer treatment in vivo.

Genotype-phenotype correlation in two Polish neonates with alveolar capillary dysplasia.

BACKGROUND: Alveolar capillary dysplasia (ACD) is a rare cause of severe pulmonary hypertension and respiratory failure in neonates. The onset of ACD is usually preceded by a short asymptomatic period. The condition is refractory to all available therapies as it irreversibly affects development of the capillary bed in the lungs. The diagnosis of ACD is based on histopathological evaluation of lung biopsy or autopsy tissue or genetic testing of FOXF1 on chromosome 16q24.1. Here, we describe the first two Polish patients with ACD confirmed by histopathological and genetic examination. CASE PRESENTATION: The patients were term neonates with high Apgar scores in the first minutes of life. They both were diagnosed prenatally with heart defects. Additionally, the first patient presented with omphalocele. The neonate slightly deteriorated around 12th hour of life, but underwent surgical repair of omphalocele followed by mechanical ventilation. Due to further deterioration, therapy included inhaled nitric oxide (iNO), inotropes and surfactant administration. The second patient was treated with prostaglandin E1 since birth due to suspicion of aortic coarctation (CoA). After ruling out CoA in the 3rd day of life, infusion of prostaglandin E1 was discountinued and immediately patient's condition worsened. Subsequent treatment included re-administration of prostaglandin E1, iNO and mechanical ventilation. Both patients presented with transient improvement after application of iNO, but died despite maximized therapy. They were histopathologically diagnosed post-mortem with ACD. Array comparative genomic hybridization in patient one and patient two revealed copy-number variant (CNV) deletions, respectively, ~ 1.45 Mb in size involving FOXF1 and an ~ 0.7 Mb in size involving FOXF1 enhancer and leaving FOXF1 intact. CONCLUSIONS: Both patients presented with a distinct course of ACD, extra-pulmonary manifestations and response to medications. Surgery and ceasing of prostaglandin E1 infusion should be considered as potential causes of this variability. We further highlight the necessity of thorough genetic testing and histopathological examination and propose immunostaining for CD31 and CD34 to facilitate the diagnostic process for better management of infants with ACD.

Dual-time-point PET/CT study protocol can improve the larynx cancer diagnosis.

AIM: To evaluate whether the sequential dual-time-point fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (DTP 18F-FDG PET/CT) study improves the differential diagnosis in the larynx. BACKGROUND: In some cases, the clinical and metabolic similarity of laryngitis and larynx cancer make differential diagnostics difficult when performing standard 18F-FDG PET/CT examinations; therefore, an additional study protocol performance seems to be of reasonable value. MATERIALS AND METHODS: 90 patients (mean age: 61 ± 11 years, range: 41-84 years): 23 women (mean age: 63 ± 10 years, range: 51-84 years) and 67 men (mean age: 61 ± 11 years, range: 41-80 years) underwent delayed 18F-FDG PET/CT examinations at 60 and 90 min post intravenous injection (p.i.) of the radiopharmaceutical 18F-FDG. We compared the metabolic activity of 90 structures divided into following groups: normal larynx (30 patients), laryngitis (30 lesions) and larynx cancer (30 tumors) with maximal and mean standardized uptake value (SUVmax, SUVmean) and the retention index (RI-SUVmax). We used the receiver operating characteristics (ROC) curve to evaluate the SUVmax cut-off values. RESULTS: The SUVmax cut-off value at 60 and 90 min p.i. of 2.3 (sensitivity/specificity: 96.4%/100%) and 2.4 (94.2%/100%), respectively, distinguished normal and abnormal metabolic activity in the larynx. When laryngitis and tumors were compared, the SUVmax cut-off values obtained after initial and delayed imaging were 3.6 (87.5%/52.0%) and 6.1 (58.3%/84%), respectively. The RI-SUVmax of 1.3% (71.4%/88.1%) suggested abnormality, while RI-SUVmax of 6.6%, malignant etiology (75.0%/80.0%). CONCLUSIONS: In this study, the sequential DTP scanning protocol improved the sensitivity and specificity of the PET/CT method in terms of differential diagnosis within the larynx.

Expression of ELF1, a lymphoid ETS domain-containing transcription factor, is recurrently lost in classical Hodgkin lymphoma.

Loss of B cell-specific transcription factors (TFs) and the resulting loss of B-cell phenotype of Hodgkin and Reed-Sternberg (HRS) cells is a hallmark of classical Hodgkin lymphoma (cHL). Here we have analysed two members of ETS domain containing TFs, ELF1 and ELF2, regarding (epi)genomic changes as well as gene and protein expression. We observed absence or lower levels of ELF1 protein in HRS cells of 31/35 (89%) cases compared to the bystander cells and significant (P < 0·01) downregulation of the gene on mRNA as well as protein level in cHL compared to non-cHL cell lines. However, no recurrent loss of ELF2 protein was observed. Moreover, ELF1 was targeted by heterozygous deletions combined with hypermethylation of the remaining allele(s) in 4/7 (57%) cell lines. Indeed, DNA hypermethylation (range 95-99%, mean 98%) detected in the vicinity of the ELF1 transcription start site was found in all 7/7 (100%) cHL cell lines. Similarly, 5/18 (28%) analysed primary biopsies carried heterozygous deletions of the gene. We demonstrate that expression of ELF1 is impaired in cHL through genetic and epigenetic alterations, and thus, it may represent an additional member of a TF network whose downregulation contributes to the loss of B-cell phenotype of HRS cells.

TP53 somatic mutations are associated with somatic mitogenome substitutions but not indels in colorectal cancer cells.

BACKGROUND: p53 is a tumour suppressor protein that is involved in many cancer-related processes. Growing evidence suggests that p53 also plays an important role in mitochondrial (mtDNA) maintenance. Somatic mitogenome mutations are frequently observed in colorectal cancer (CC) cells. Thus, it was important to determine whether somatic mtDNA changes are associated with TP53 mutational status. METHODS: In the present study, we analysed the TP53 gene in 67 CC patients, for whom mitogenome haplotypes were previously described. In total, 134 TP53 sequences (of cancer and matched normal specimens) were determined using the dideoxy method. RESULTS: Nine hereditary polymorphisms in the TP53 gene were detected in normal colon cells. None of them (neither alleles, nor genotypes) was associated with somatic mitogenome mutations in CC cells. Moreover, 42 somatic TP53 mutations were found in approximately 36% of CC tissues. These somatic changes were significantly more frequent in CC cells with somatic mtDNA mutations (p = 0.0069). Furthermore, we show that only mitochondrial somatic substitutions (p = 0.0017), but not indels (p > 0.05), were associated with somatic TP53 mutations. CONCLUSIONS: The results of the present study suggest that changes in TP53 may modify p53 properties, which may result in the accumulation of somatic substitutions in CC mitogenomes.

Relationship between Helicobacter pylori Infection and Plasmacytoid and Myeloid Dendritic Cells in Peripheral Blood and Gastric Mucosa of Children.

PURPOSE: To investigate the frequency and activation status of peripheral plasmacytoid DCs (pDCs) and myeloid DCs (mDCs) as well as gastric mucosa DC subset distribution in Helicobacter pylori- (H. pylori-) infected and noninfected children. MATERIALS AND METHODS: Thirty-six children were studied; twenty-one had H. pylori. The frequencies of circulating pDCs (lineage-HLA-DR+CD123+) and mDCs (lineage-HLA-DR+CD11c+) and their activation status (CD83, CD86, and HLA-DR expression) were assessed by flow cytometry. Additionally, the densities of CD11c+, CD123+, CD83+, CD86+, and LAMP3+ cells in the gastric mucosa were determined by immunohistochemistry. RESULTS: The frequency of circulating CD83+ mDCs was higher in H. pylori-infected children than in the noninfected controls. The pDCs demonstrated upregulated HLA-DR surface expression, but no change in CD86 expression. Additionally, the densities of gastric lamina propria CD11c+ cells and epithelial pDCs were increased. There was a significant association between frequency of circulating CD83+ mDCs and gastric lamina propria mDC infiltration. CONCLUSION: This study shows that although H. pylori-infected children had an increased population of mature mDCs bearing CD83 in the peripheral blood, they lack mature CD83+ mDCs in the gastric mucosa, which may promote tolerance to local antigens rather than immunity. In addition, this may reduce excessive inflammatory activity as reported for children compared to adults.

Diagnostic difficulties in cases of papillary urothelial neoplasm of low malignant potential, urothelial proliferation of uncertain malignant potential, urothelial dysplasia and urothelial papilloma: A review of current literature.

Tumours of the urinary tract are the fifth most frequent type of cancer. The most common types are urothelial tumours, among which, non-invasive urothelial neoplasms represent 45% of all cases. The 2016 WHO classification of urinary tract tumours introduced new classifications of non-invasive lesions. Besides urothelial papilloma (UP) and papillary urothelial neoplasm of low malignant potential (PUNLMP), as described in the former classification, the new classification also includes new entities such as urothelial proliferation of uncertain malignant potential (UPUMP) and urothelial dysplasia (UD). Of the aforementioned, UPUMP is the lesion that most commonly progresses, but solely to non-invasive carcinomas. UD is associated with a high risk of progression to invasive carcinoma. Understanding the biological character, and establishing the correct differential diagnosis in cases of non-invasive, non-cancerous lesions of the urinary bladder, will be of importance in establishing outcome predictions for future patients. A systematic review of the current literature allows us to systematize genetic, morphologic and prognostic factors of such lesions. Moreover, the collected data provide the basis for a proposed diagnostic algorithm which facilitates quick and effective differential diagnoses in cases of non-invasive non-cancerous urinary bladder lesions.

Salivary levels and immunohistochemical expression of selected angiogenic factors in benign and malignant parotid gland tumours.

OBJECTIVES: Angiogenesis underlies tumour growth and metastasis through hepatocyte growth factor (HGF), epithelial growth factor (EGF), and vascular endothelial growth factor (VEGF). The aim of this study was to determine the levels of VEGF, EGF, HGF, HGFR (hepatocyte growth factor receptor), and SRSF1 (serine-rich protein splicing factor-1) in patients with parotid gland tumours and in healthy controls via ELISA in parotid saliva. Immunohistochemical expression of anti-angiogenic isoform of VEGF165b subunit, VEGFR1, VEGFR2, and microvessel density (CD34) were assessed in the tumour tissue and in the non-tumorous surrounding margins. MATERIALS AND METHODS: The study included 48 patients with benign and malignant parotid gland tumours and 15 healthy controls. RESULTS: Comparison of VEGF, EGF, and HGF in tumour and non-tumorous tissues showed no significant differences and no correlations with tumour stage. The salivary VEGF concentration was significantly higher in patients with pleomorphic adenoma and Warthin's tumour. No significant correlation was found between expression of VEGF165b and VEGFR2 in tumours and non-tumor surgical margins. CONCLUSIONS: The increased salivary VEGF reflects changes in affected parotid glands, but it cannot be used as a prognostic and differentiative factor for parotid tumours. CLINICAL RELEVANCE: Reciprocal relations between growth factors suggest an overlapping pathway of secretion and activity.

Green tea extract prevents the development of nonalcoholic liver steatosis in rats fed a high-fat diet.

Green tea contains many polyphenolic constitutes, which might prevent non-alcoholic fatty liver disease (NAFLD). We aimed to investigate whether green tea extract (GTE) given at doses reflecting habitual consumption of green tea beverages prevents development of NAFLD in rats fed a high-fat diet (HFD). Twenty-four male Wistar rats were randomly divided into four equal groups (two study and two control groups). The study groups received a HFD (approximately 50% energy from fat), enriched with 1.1% and 2.0% GTE, respectively, for a total of 56 days. The control groups were fed a HFD alone and normal standardised diet (low-fat diet), respectively, for the same period of time. The percentage of hepatocytes affected by steatosis in the HFD group (median [1st-3rd quartile]: 25% [12-34%]) was higher (p < 0.033 and p < 0.050, respectively) than in the HFD-2.0%GTE group (9% [3-18%]) and normal diet group (10% [5-18%]). No significant differences were observed for the group consuming HFD-1.1%GTE, in which intermediate results were observed (15% [4-30%]). This finding points towards the hepatoprotective potential of GTE in preventing dietary-induced liver steatosis. In view of the increasing incidence of overweight and obesity a simple and cheap dietary modification, such as GTE supplementation, could prove to be useful clinically.

Will Rogers phenomenon in the oesophageal cancer patients staging - CT versus 18F-FDG PET/CT: retrospective study.

OBJECTIVE: The oesophageal cancer is one of the most common and aggressive malignancies, especially in elder man. The method of choice in diagnosis of the oesophageal cancer patients are the contrast-enhanced computed tomography (CT) and the 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) examinations. AIM: This study is to evaluate and compare the contrast-enhanced CT and the 18F-FDG PET/CT methods of imaging in terms of the oesophageal cancer staging and restaging using the eighth edition of the tumor-node-metastasis (TNM) classification. MATERIALS AND METHODS: The studied group consisted of 25 retrospectively analyzed patients (23 men, 2 women; mean age±SD: 60±11 years, range: 33-78 years, median: 62 years, p=0.09) who underwent the contrast-enhanced CT and the 18F-FDG PET/CT scanning within one to eight weeks. All mentioned lesions were histopathologically examined. Among these patients, 12 did not receive any treatment and 13 subjects have been treated with the chemotherapy and the external beam radiotherapy using comparable therapeutic protocols. RESULTS: In 13 subjects PET/CT method occurred as more sensitive in terms of pre- and posttreatment staging than CT and in 10 from 13 cases, involving the 18F-FDG PET/CT imaging into diagnostic management affected the therapeutic protocol. In 11 cases both methods showed comaparable or similar stage of the disease and in 1 patient both methods showed no pathology. CONCLUSION: In this material, the 18F-FDG PET/CT seems to be more accurate in terms of staging in case of the oesophageal cancer TNM classification.

Assessment of cartilage invasion in case of laryngeal cancer by means of longitudinal sectioning for histopathology - Clinical implications.

AIM: The aim of the study was to assess the accuracy of radiological diagnosis of laryngeal cartilage infiltration by histopathological examination of laryngeal specimen after total laryngectomy. BACKGROUND: Despite the development of new medical technologies and significant clinical advances allowing early diagnosis and treatment of laryngeal cancer, mortality is still on the rise. Neoplastic infiltration of the laryngeal cartilages is the most common source of error in the assessment of cancer staging. Furthermore, cartilage invasion is listed as a contraindication to partial surgical techniques as well as radiotherapy. MATERIALS AND METHODS: The study was carried out on 21 larynges following total laryngectomy. Before taking the decision to perform surgery, high-resolution CT scans were performed in all cases. An extended histopathological examination was conducted using a unique vertical cross-section of the whole larynx. RESULTS: Pathology reported 2 cases of arytenoid cartilage invasion, 5 cases of cricoid cartilage invasion, 12 cases of thyroid cartilage penetration, 1 case of internal cortex invasion and 9 cases of extra-laryngeal spread. CT imaging identified 8 of 13 cases (61.5%) of pathologically proven invasion of thyroid cartilage and only 2 cases (2/9, 22%) of extra-laryngeal spread. According to CT results, arytenoid cartilage invasion was correctly identified in 2 cases, cricoid cartilage invasion in 4 (4/5, 80%). The positive predictive values for thyroid, cricoid and arytenoid cartilage invasion and penetration were 80%, 66.7% and 50%, respectively. In case of pre-laryngeal spread the positive predictive value was 100%. CONCLUSION: Despite increasingly advanced methods involved in the diagnosis of laryngeal cancer, many discrepancies may be observed between the radiological and histopathological assessments. CT imaging has limitations especially in thyroid cartilage penetration and extra-laryngeal spread assessment in advanced laryngeal cancer cases. An extended histopathological examination, involving vertical cross-sections of the whole larynx is a very precise study that allows a precise determination of local cancer staging (T).

Mitogenomic differences between the normal and tumor cells of colorectal cancer patients.

So far, a reliable spectrum of mitochondrial DNA mutations in colorectal cancer cells is still unknown, and neither is their significance in carcinogenesis. Indeed, it remains debatable whether mtDNA mutations are "drivers" or "passengers" of colorectal carcinogenesis. Thus, we analyzed 200 mitogenomes from normal and cancer tissues of 100 colorectal cancer patients. Minority variant mutations were detected at the 1% level. We showed that somatic mutations frequently occur in colorectal cancer cells (75%) and are randomly distributed across the mitochondrial genome. Mutational signatures of somatic mitogenome mutations suggest that they might arise through nucleotide deamination due to oxidative stress. The majority of somatic mutations localized within the coding region (in positions not known from the human phylogeny) and was potentially pathogenic to cell metabolism. Further analysis suggested that the relaxation of negative selection in the mitogenomes of colorectal cancer cells may allow accumulation of somatic mutations. Thus, a shift in glucose metabolism from oxidative phosphorylation to glycolysis may create advantageous conditions for accumulation of mtDNA mutations. Considering the fact that the presence of somatic mtDNA mutations was not associated with any clinicopathological features, we suggested that mtDNA somatic mutations are "passengers" rather than the cause of colorectal carcinogenesis.

Recurrent transcriptional loss of the PCDH17 tumor suppressor in laryngeal squamous cell carcinoma is partially mediated by aberrant promoter DNA methylation.

Protocadherins are cell-cell adhesion molecules encoded by a large family of genes. Recent reports demonstrate recurrent silencing of protocadherin genes in tumors and provide strong arguments for their tumor supresor functionality. Loss of protocadherins may contribute to cancer development not only by altering cell-cell adhesion, that is a hallmark of cancer, but also by enhancing proliferation and epithelial mesenchymal transition of cells via deregulation of the WNT signaling pathway. In this study we have further corroborated our previous findings on the involvement of PCDH17 in laryngeal squamous cell carcinoma (LSCC). We used bisulfite pyrosequencing to analyze a cohort of primary LSCC tumors for alterations in PCDH17 promoter DNA methylation as an alternative gene inactivation mechanism to the homozygous deletions reported earlier. Moreover, we analyzed primary LSCC samples by immunohistochemistry for PCDH17 protein loss. We identified recurrent elevation of PCDH17 promoter DNA methylation in 32/81 (40%) primary tumors (P < 0.001) and therein hypermethylation of 12 (15%) cases in contrast to no tumor controls (n = 24) that were all unmethylated. Importantly, DNA demethylation by decitabine has restored low level PCDH17 expression in LSCC cell lines. In conclusion, we provide a mechanistic explanation of recurrently observed PCDH17 silencing in LSCC by demonstrating the role of promoter methylation in this process. In light of these findings and recent reports showing that PCDH17 methylation is detectable in serum of cancer patients we suggest that testing PCDH17 DNA methylation might serve as a potential biomarker in LSCC.

Assessment of Peritoneal Membrane Arteriolar Structure in Conjunction with Traditional Cardiovascular System Evaluation in Chronic Kidney Disease (CKD) Stage 5 Patients.

BACKGROUND/AIMS: Cardiovascular complications are responsible for increased mortality and morbidity in chronic kidney disease (CKD) patients. Functional and structural changes of peritoneal membrane are reported in CKD patients both on conservative treatment and on renal replacement therapy (RRT). The aim of the study was to assess the structure of peritoneal membrane small arteries (precapillary arterioles) in diabetic and non-diabetic CKD stage 5 patients before initiation of peritoneal dialysis (PD) and evaluate its relationship with heart and large arteries abnormalities and with selected biochemical parameters. METHODS: Evaluation of 42 CKD stage 5 patients before starting PD. Diabetic (n=26) and non-diabetic (n=16) patients were compared. Peritoneal membrane samples were taken during Tenckhoff catheter insertion. Histopathological evaluation of peritoneal precapillary arterioles (arteriolar evaluation) with measurement of wall thickness (WT) and calculation of lumen/vessel (L/V) ratio was performed in each patients. Echocardiography, intima media thickness (IMT), pulse wave velocity (PWV), ambulatory blood pressure monitoring (ABPM) and biochemical parameters assessment: serum albumin (SA), total cholesterol (TCH), hemoglobin (Hgb), parathormone (PTH), serum calcium (Ca), serum phosphorus (P), transferrin saturation (TSAT%), C-reactive protein (CRP) were performed in each participant. RESULTS: There were no statistically significant differences in peritoneal membrane arteriolar indices - wall thickness (WT) and L/V ratio between investigated groups. There was statistically significant higher PWV value in diabetic patients. There were no statistically significant differences in echocardiographic indices, IMT, laboratory data in analyzed groups. There were some linear correlations between: PWV vs IMT (R=0,84; p=0,0006); PWV vs PP (R=0,58; p=0,03) in non-diabetic and linear correlation between: PWV vs age (R=0,75; p=0,02); WT vs DP (R=-0,93; p=0,001); WT vs DBP ( R=0,64; p=0,04) in diabetic group. CONCLUSION: Peritoneal membrane arteriolar damage seems to be an integrated part of cardiovascular system damage in CKD stage 5 patients.