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It is now widely accepted that white adipose tissue (WAT) is not merely a fuel storage organ, but also a key component of metabolic homoeostatic mechanisms. Apart from its major role in lipid and glucose metabolism, adipose tissue is also involved in a wide array of other biological processes. The hormones and adipokines, as well as other biologically active agents released from fat cells, affect many physiological and pathological processes. WAT is neither uniform nor inflexible because it undergoes constant remodelling, adapting the size and number of adipocytes to changes in nutrients' availability and hormonal milieu. Fat depots from different areas of the body display distinct structural and functional properties and have disparate roles in pathology. The two major types of WAT are visceral fat, localized within the abdominal cavity and mediastinum, and subcutaneous fat in the hypodermis. Visceral obesity correlates with increased risk of insulin resistance and cardiovascular diseases, while increase of subcutaneous fat is associated with favourable plasma lipid profiles. Visceral adipocytes show higher lipogenic and lipolytic activities and produce more pro-inflammatory cytokines, while subcutaneous adipocytes are the main source of leptin and adiponectin. Moreover, adipose tissue associated with skeletal muscles (intramyocellular and intermuscular fat) and with the epicardium is believed to provide fuels for skeletal and cardiac muscle contraction. However, increased mass of either epicardial or intermuscular adipose tissue correlates with cardiovascular risk, while the presence of the intramyocellular fat is a risk factor for the development of insulin resistance. This review summarizes results of mainly human studies related to the differential characteristics of various WAT depots.

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Common molecular changes in cancer cells are high carbon flux through the glycolytic pathway and overexpression of fatty acid synthase, a key lipogenic enzyme. Since glycerol 3-phosphate dehydrogenase creates a link between carbohydrates and the lipid metabolism, we have investigated the activity of glycerol 3-phosphate dehydrogenase and various lipogenic enzymes in human bladder cancer. The data presented in this paper indicate that glycerol 3-phosphate dehydrogenase activity in human bladder cancer is significantly higher compared to adjacent non-neoplastic tissue, serving as normal control bladder tissue. Increased glycerol 3-phosphate dehydrogenase activity is accompanied by increased enzyme activity, either directly (fatty acid synthase) or indirectly (through ATP-citrate lyase, glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and citrate synthase) involved in fatty acid synthesis. Coordinated upregulation of glycerol 3-phosphate dehydrogenase and lipogenic enzymes activities in human bladder cancer suggests that glycerol 3-phosphate dehydrogenase supplies glycerol 3-phosphate for lipid biosynthesis.

Inflammatory bowel disease (IBD) is a group of inflammatory conditions of the gastrointestinal tract of unclear aetiology of which two major forms are Crohn's disease (CD) and ulcerative colitis (UC). CD and UC are immunologically distinct, although they both result from hyperactivation of proinflammatory pathways in intestines and disruption of intestinal epithelial barrier. Members of the tumour necrosis factor superfamily (TNFSF) are molecules of broad spectrum of activity, including direct disruption of intestinal epithelial barrier integrity and costimulation of proinflammatory functions of lymphocytes. Tumour necrosis factor (TNF) has a well-established pathological role in IBD which also serves as a target in IBD treatment. In this review we discuss the role of TNF and other TNFSF members, notably, TL1A, FasL, LIGHT, TRAIL, and TWEAK, in the pathogenesis of IBD.

Spherical cultures (SCs) can be regarded in cancer research as a link between in vitro investigations on cancer lines and in vivo studies of tumor development. SCs are believed to mimic tumor architecture and to be enriched in cancer stem cell-like cells (CSC-like cells). In the present study we characterized colonospheres derived from colorectal cancer (CRC) cell lines, and we confirmed the ability of HCT116 and HT29 cell lines to form spheres within serum-free medium, however, the detailed analysis presented the major differences concerning their characteristics including morphology, phenotype, proliferative potential, distribution in the cell cycle phases and spherogenicity. Moreover, after we magnetically separated CD133+ and CD133- cells we could conduct the analogical analysis as we performed for the original cells. We observed that all cellular fractions unveiled sphere formation capacity, even when cultured in limited number of cells per well and only SCs originated from CD133+ fraction resembled morphologically the parental spheres. Both CD133+ and CD133- subsets derived from HCT116 line were more enriched in cells in G0/G1 phase of the cell cycle in comparison to their HT29 analogues. Additionally, proliferative potential also varied amongst all studied fractions. Surprisingly, 3-D invasion assay revealed that only HCT116-derived populations were able to migrate into extended regions of Matrigel Matrix confirming their higher aggressiveness. Our results provided comprehensive characterization of CRC cell lines culture in adherent and spherical forms and, what seems to be the most advantageous, the comparison of two distinct fractions after magnetic separation. As we found the specific features of cells presented line- and expansion mode-dependency, thus, such complete description might appear crucial before CRC lines would be involved into sophisticated assays, especially focused on potentially novel therapeutic agents targeting CSC-like cells.

Abstract. Clear cell renal cell carcinoma (ccRCC) is the most common subtype of RCC (70-80%). Yes-associated protein 1 (YAP1) protein is a nuclear effector of the Hippo pathway and acts as a transcriptional co-activator of genes involved in the processes of growth and development of tissues. Hippo signaling, with its key kinases, MST2 and large tumor suppressor kinase 1 (LATS1), plays a significant role in the negative regulation of the amount and activity of YAP1 protein. Components of the Hippo pathway and YAP1 levels are frequently dysregulated in a variety of tumors, suggestive of their possible involvement in carcinogenesis. Our aim was to evaluate gene and protein expression profiles of YAP1, MST2 and LATS1 and the methylation status of MST2 and LATS1 promoters in ccRCC. mRNA levels of MST2, LATS1 and YAP1 genes were assessed in the tumor and matched normal kidney tissues of 86 patients, and in 12 samples of local metastases by quantitative PCR (qPCR). Proteins were semi-quantified in 58 patient samples by western blotting. Hypermethylation of LATS1 and MST2 promoters was measured by methylation-specific high-resolution-melting qPCR. We found that LATS1 promoter hypermethylation, decreased LATS1 mRNA/protein and increased YAP1 mRNA/protein levels in tumor samples were associated with higher TNM and Fuhrman's stages and patient survival. Higher YAP1 mRNA levels were associated with poor outcome (HR=4.03, p=0.036). No changes in MST2 (promoter/ mRNA/protein) were found. We propose that deregulation of LATS1 and YAP1 expression is associated with ccRCC progression and poor patient survival. Measurement of YAP1 mRNA levels in paired tumor-normal kidney tissue samples may serve as a new prognostic factor in ccRCC.

The role of autophagy is to degrade damaged or unnecessary cellular structures. Both in vivo and in vitro studies suggest a dual role of autophagy in cancer—it may promote the development of neoplasms, but it may also play a tumor protective function. The mechanism of autophagy depends on the genetic context, tumor stage and type, tumor microenvironment, or clinical therapy used. Autophagy also plays an important role in cell death as well as in the induction of chemoresistance of cancer cells. The following review describes the extensive autophagic cell death in relation to dietary polyphenols and cancer disease. The review documents increasing use of polyphenolic compounds in cancer prevention, or as agents supporting oncological treatment. Polyphenols are organic chemicals that exhibit antioxidant, anti-inflammatory, anti-angiogenic, and immunomodulating properties, and can also initiate the process of apoptosis. In addition, polyphenols reduce oxidative stress and protect against reactive oxygen species. This review presents in vitro and in vivo studies in animal models with the use of polyphenolic compounds such as epigallocatechin-3-gallate (EGCG), oleuropein, punicalgin, apigenin, resveratrol, pterostilbene, or curcumin and their importance in the modulation of autophagy-induced death of cancer cells.