Extensive mitochondrial heteroplasmy in hybrid water frog (Pelophylax spp.) populations from Southeast Europe.

Water frogs of the genus Pelophylax (previous Rana) species have been much studied in Europe for their outstanding reproductive mechanism in which sympatric hybridization between genetically distinct parental species produces diverse genetic forms of viable hybrid animals. The most common hybrid is P. esculentus that carries the genomes of both parental species, P. ridibundus and P. lessonae, but usually transfers the whole genome of only one parent to its offsprings (hybridogenesis). The evolutionary cost of transfer of the intact genome and hence the hemiclonal reproduction is the depletion of heterozygosity in the hybrid populations. Pelophylax esculentus presents an excellent example of the long-term sustained hybridization and hemiclonal reproduction in which the effects of the low genetic diversity are balanced through the novel mutations and periodic recombinations. In this study, we analyzed the mitochondrial (mt) and microsatellites DNA variations in hybrid Pelophylax populations from southern parts of the Pannonian Basin and a north-south transect of the Balkan Peninsula, which are home for a variety of Pelophylax genetic lineages. The mtDNA haplotypes found in this study corresponded to P. ridibundus and P. epeiroticus of the Balkan - Anatolian lineage (ridibundus-bedriagae) and to P. lessonae and a divergent lessonae haplotype of the lessonae lineage. The mtDNA genomes showed considerable intraspecific variation and geographic differentiation. The Balkan wide distributed P. ridibundus was found in all studied populations and its nuclear genome, along with either the lessonae or the endemic epeiroticus genome, in all hybrids. An unexpected finding was that the hybrid populations were invariably heteroplasmic, that is, they contained the mtDNA of both parental species. We discussed the possibility that such extensive heteroplasmy is a result of hybridization and it comes from regular leakage of the paternal mtDNA from a sperm of one species that fertilizes eggs of another. In this case, the mechanisms that protect the egg from heterospecific fertilization and further from the presence of sperm mtDNA could become compromised due to their differences and divergence at both, mitochondrial and nuclear DNA. The heteroplasmy once retained in the fertilized egg could be transmitted by hybrid backcrossing to the progeny and maintained in a population over generations. The role of interspecies and heteroplasmic hybrid animals due to their genomic diversity and better fitness compare to the parental species might be of the special importance in adaptations to miscellaneous and isolated environments at the Balkan Peninsula.

Expression of miRNAs involved in angiogenesis, tumor cell proliferation, tumor suppressor inhibition, epithelial-mesenchymal transition and activation of metastasis in bladder cancer.

PURPOSE: miRNAs are noncoding RNAs that posttranscriptionally regulate gene expression. Altered expression and function have been observed in bladder cancer. We analyzed the expression profile of a group of miRNAs involved in bladder cancer angiogenesis, tumor cell proliferation, tumor suppressor inhibition, epithelial-mesenchymal transition and metastasis activation. Prognostic and diagnostic value, and validated targets were further examined. MATERIALS AND METHODS: Using quantitative real-time polymerase chain reaction 77 bladder cancer cases and 77 matched tumor associated normal samples were investigated to determine the expression of miR-10b, 19a, 19b, 21, 126, 145, 205, 210, 221, 296-5p and 378. The relationship between miRNA expression, patient survival and tumor pathological features was also examined. RESULTS: miR-10b, 19a, 126, 145, 221, 296-5p and 378 were significantly down-regulated in bladder cancer compared to adjacent normal urothelium. miR-145 was the most down-regulated microRNA of this group. miR-19b, 21, 205 and 210 showed no significant difference between the 2 tissue types. High miR-21 expression correlated with worse overall patient survival (p = 0.0099). Multivariate analysis revealed that miR-21, 210 and 378 may serve as independent prognostic factors for overall patient survival (p = 0.005, 0.033 and 0.012, respectively). miR-21 and 378 may serve as independent prognostic factors for recurrence (p = 0.030 and 0.031, respectively). miR-145, 221, 296-5p and 378 showed the best combined ROC curves for specificity and sensitivity. miRWalk analysis was used to identify validated miRNA target genes. Further Gene Ontology enrichment revealed the main classes of biological functions of these validated targets. CONCLUSIONS: Most miRNAs analyzed are down-regulated in bladder cancer. They may serve as candidate biomarkers for diagnostic and prognostic purposes in the future.

HPV, KRAS mutations, alcohol consumption and tobacco smoking effects on esophageal squamous-cell carcinoma carcinogenesis.

Esophageal squamous-cell carcinoma (ESCC) is an invasive neoplastic disease generally associated with poor survival rates. The incidence of ESCC is characterized by marked geographic variation, with highest rates noted in developing Southeastern African, Central and Eastern Asian countries. In the developed Western European and North American regions where there is a low disease incidence, heavy alcohol and cigarette consumption constitute major risk factors. The toxic effects of both these risk factors cause chronic irritation and inflammation of the esophageal mucosa, while at the cellular level they further confer mutagenic effects by the activation of oncogenes (e.g., RAS mutations), inhibition of tumor-suppressor genes, and profound DNA damage. Viral infections, particularly with human papillomavirus, may activate specific antiapoptotic, proliferative and malignant cellular responses that may be intensified in combination with the effects of alcohol and tobacco. In countries with a high ESCC incidence, low socioeconomic status and an inadequate diet of poorly preserved food are combined with basic nutritional deficiencies and inadequate medical treatment. These conditions are favorable to the above-mentioned risk factors implicated in ESCC development, which may be present and/or habitually used in certain populations. New perspectives in epidemiological studies of ESCC development and its risk factors allow genome-wide research involving specific environments and habits. Such research should consist of adequately large and representative samples, should use newly designed informative genetic markers, and apply genomic variation analysis of the functional transcripts involved in malignant cell cycle regulation and neoplastic transformation in the multi-step process of ESCC carcinogenesis.

ERα36, a new variant of the ERα is expressed in triple negative breast carcinomas and has a specific transcriptomic signature in breast cancer cell lines.

Triple negative breast cancer is deprived of estrogen receptor alpha (ERα), progesterone receptor (PR) and HER-2 protein. It constitutes the most heterogeneous and aggressive group of breast carcinomas, for which identification of novel characteristics and characterization of putative targets becomes very demanding. In the present work we have assayed the expression of ERα36, a recently identified ERα variant of 36kDa, in a series of triple negative breast cancers, in relation to the clinical behavior and other clinico-pathological features of the tumors. While widely expressed within the cytoplasm in almost all tumors, we found that exclusively the membrane/submembrane expression of the receptor exhibits a correlation with patient's survival. Moreover, membrane ERα36 correlates in an inverse manner with the expression of miRNA210, a pro-angiogenic miR, with high prognostic relevance in triple negative carcinomas. A thorough transcriptomic, pharmacological-based approach in breast cancer cell lines, revealed an early (direct) transcriptional signature of the receptor activation, related to immune system processes and T-cell differentiation, RNA biosynthesis, regulation of metabolism, VEGF signaling and regulation of the cell cycle, with a down-regulation of CREB, NFκB and STATs transcription factors. Finally, ERα36 expression is not limited within breast cancer epithelial linen, but is equally identified in tumor vasculature, peritumoral fat tissue, lymphocytic infiltrate and stromal fibroblasts. In light of the above, ERα36 could represent a major counterpart in triple negative breast cancer.

Histological types and age distribution of lung cancer operated patients over a 20-year period: a pathohistological based study.

INTRODUCTION: Lung cancer is the leading cause of death from malignancy in Serbia. OBJECTIVE: This is a retrospective analysis of lung cancer epidemiological changes regarding to its histological type and patients' age of both genders. Data were based on surgically treated lung cancer patients from 1985 to 2005. METHODS: Data were collected from 972 pathohistological reports of operated patients of both genders divided into age groups. Histological types of lung cancer were distributed in four major groups: squamous cell cancer (SCC), adenocarcinoma (AC), small cell cancer (SCLC) and other rare histological types. Both genders together and separately were analysed. Chi-square with the level of significance p<0.05 and chi-square test for trends were used as statistical methods. RESULTS: SCC predominated in both genders; in 44.7% females and 68.0% males. AC was less frequently diagnosed (21.8%) than SCC (64.0%) in both genders and all age groups. The most frequently operated patients were aged between 51 and 60 years (36.6%) with SCC and AC predominance. Three patients with SCLC were operated in 61-70 age-group. In age-group up to 30 years, three (0.5%) patients were operated on for SCC and other rare lung tumours, respectively. Predominance of other rare lung tumours was established in 51-60 age-group, 25% of patients of both genders. CONCLUSION: SCC is the most frequent histological type of lung cancer found in all age groups and in both genders of surgically treated patients.

Detection of the TNFSF members BAFF, APRIL, TWEAK and their receptors in normal kidney and renal cell carcinomas.

In advanced renal cell carcinoma (RCC), surgery combined with systemic chemotherapy and immunotherapy have had limited effectiveness. Therapeutic modalities targeting VEGF, PDGF, and c-kit using tyrosine kinase inhibitors and m-TOR using specific biologic factors are in development. Therapeutic approaches targeting TNF-alpha have shown limited efficacy, while anti-TRAIL (TNFSF10) antibodies have shown enhanced activity. The presence and potential significance of other members of the TNFSF has not been investigated. Here, we assayed the TNFSF members APRIL, BAFF, TWEAK and their receptors (BCMA, TACI, BAFFR, Fn14) in 86 conventional type clear cell RCC, using immunohistochemistry and correlated our findings with histological data and, in a limited series, follow-up of patients. We observed a differential expression of these TNFSF ligands and receptors in cancerous and non-cancerous structures. BAFF was found in all RCC; APRIL expression is associated with an aggressive phenotype, correlating negatively with patients' disease-free survival, while TWEAK and its receptor Fn14 are heterogeneously expressed, correlating negatively with the grade and survival of RCC patients. This is the first study, presenting together the TNFSF members APRIL, BAFF, TWEAK and their receptors in different areas of normal renal tissue and RCC, suggesting a potential role of these TNFSF members in renal tumor biology.

MicroRNA expression analysis in triple-negative (ER, PR and Her2/neu) breast cancer.

miRNAs are small, regulatory molecules approximately 21-24 nucleotides in length. They function at the post-transcriptional level by controlling the expression of more than 50% of human protein-coding genes and play an essential role in cell signaling pathways. The objective of the present study was to explore the expression profile of oncomiRs and tumor-suppressor miRs, and to define their possible correlations in triple-negative (ER, PR and Her2/neu) primary breast cancers. Forty-nine primary triple-negative breast cancer cases, along with 34 matched tumor-associated normal samples were investigated for the expression of 9 miRNAs using qPCR. Relationships between the expression of miR-10b, miR-21, miR-122a, miR-145, miR-205, miR-210, miR-221, miR-222 and miR-296 and the pathologic features of the tumors were examined, as were the influences of miR expression on patient overall and cancer-specific survival. miR-21, miR-210 and miR-221 were significantly overexpressed, whereas miR-10b, miR-145, miR-205, miR-122a were significantly underexpressed in the triple-negative primary breast cancers. Significant correlations among all of the studied miRs were scored both in the breast cancer and control tissue. Expression of miR-222 and miR-296 did not exhibit any significant difference between the breast cancer and normal tissue. There was a non-significant trend for high expression levels of the microRNAs, miR-21, miR-210, miR-221 and miR-222, to be associated with worse patient disease-free and overall survival. miR-21, miR-210 and miR-221 expression plays a significant role in triple- negative primary breast cancers.

Lung cancer in women: histological type and patient age from 1985 to 2005.

The aim of the study was to analyse changes in histological type and age of presentation in female lung cancer patients during a period of 20 years. The obtained results are compared with those available from the literature published in various parts of the world.

[Incindentally detected Castleman disease in a patient with allergic rhinosinusitis].

INTRODUCTION: Castleman disease was for the first time described in 1956 as a mediastinal tumour mass. Etiology of this disease is still unknown. The disease can be solitary and multicentric or rarely of a mixed type. The former is often of hyaline vascular type, while the latter is of plasma cell type. CASE REPORT: Castleman disease was diagnosed in a 26-year old male patient when a well defined shadow was incidentally detected in the middle lobe of the right lung. A year before, he was diagnosed with allergic rhinitis to Ambrosia. Two years after surgery the patient was feeling well, and was without any recurrence, however, allergic rhinitis still persisted. CONCLUSION: Castleman disease can occur in any organ containing lymph tissues. Most frequently the disease is described as mediastinal, rarely as an intrapulmonary tumorous mass, and it is most frequently seen in younger persons. The solitary type of Castleman disease is surgical treatable with a prospect of good prognosis, while the multicentric and mixed types recur despite treatment with cortisone, irradiation and cytostatics. As the association between Castleman disease and allergic diseases has not been confirmed up-to-now, it could be concluded that this patient suffered from two separated diseases.

[Pulmonary sclerosing haemangioma--case report].

INTRODUCTION: Sclerosing haemangioma is a benign tumour, also known under the term "pneumocytoma". It is mostly notified in older females and is usually solitary. According to the histological appearance, sclerosing haemangioma could be: papillary, sclerotic, solid and haemorrhagic. CASE OUTLINE: A 68-year-old female patient was radiologically diagnosed with coin lesion in the lower right lobe. Lower right lobectomy was performed after clinical investigations. In pulmonary parenchyma, there was found a well circumscribed node of up to 35 mm in maximal diameter. The tumour was histologically established as sclerosing haemangioma, containing two types of cells with the same immunophenotype. A multiple type of tumour was excluded by postoperative radiological examinations. Two years after surgery, the patient is without disease recurrence. CONCLUSION: Sclerosing haemangioma should be considered in patients with radiologically diagnosed "coin-like" lesions of a solid as well as multiple type.

[Alveolar adenoma -- a rare lung tumour].

INTRODUCTION: Alveolar adenoma belongs to the group of benign epithelial tumours. Histogenesis of alveolar adenoma is a combination of proliferation of alveolar pneumocytes and fibrous tissue originating from septal mesenchyma. CASE OUTLINE: A sixty-nine-year old female patient was hospitalizied for clinical examination and surgery of well defined and homogenous tumourous lesion in the right middle lobe causing pleural pain. Bronchoscopic examination with biopsy did not resolve aetiology of the disease. Tumourectomy was performed. Tumourous nodule had a multicystic appearance and histologically, histochemically and immunohistochemically, an alveolar adenoma was estimated. Five years after surgery, the patient feels well, without respiratory symptoms and signs of recurrence or malignant alteration, respectively. CONCLUSION: Alveolar adenoma is a rare benign lung tumour, most frequently presented as a solitary pulmonary nodule. After complete surgery, the tumour neither relapses nor malignantly alters. Surgical excision is curative. It is necessary to take into consideration alveolar adenoma, too, when a solitary pulmonary nodule is diagnosed.