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SummaryDefective centrosome function can disrupt embryonic kidney development, by causing changes to the renal interstitium that leads to fibrocystic disease pathologies. Yet, it remains unknown how mutations in centrosome genes impact kidney interstitial cells. Here, we examined the consequences of defective centrosome biogenesis on stromal progenitor cell growth, differentiation and fate. Conditional deletion ofCep120, a ciliopathy gene essential for centrosome duplication, in the stromal mesenchyme resulted in reduced abundance of pericytes, interstitial fibroblasts and mesangial cells. This was due to delayed mitosis, increased apoptosis, and changes in Wnt and Hedgehog signaling essential for differentiation of stromal lineages.Cep120ablation resulted in hypoplastic kidneys with medullary atrophy and delayed nephron maturation. Finally, centrosome loss in the interstitium sensitized kidneys of adult mice, causing rapid fibrosis via enhanced TGF-β/Smad3-Gli2 signaling after renal injury. Our study defines the cellular and developmental defects caused by centrosome dysfunction in embryonic kidney stroma.Graphical AbstractHighlightsDefective centrosome biogenesis in kidney stroma causes:Reduced abundance of stromal progenitors, interstitial and mesangial cell populationsDefects in cell-autonomous and paracrine signalingAbnormal/delayed nephrogenesis and tubular dilationsAccelerates injury-induced fibrosis via defective TGF-β/Smad3-Gli2 signaling axis

Autosomal Dominant Polycystic Kidney Disease (ADPKD) is an inherited monogenic disorder accounting for ∼5% of patients with renal failure. Yet, therapeutics for the treatment of ADPKD remain limited. ADPKD tissues display defects in the biogenesis of the centrosome which causes genome instability, aberrant ciliary signaling, and secretion of pro-inflammatory factors that drive cyst growth and fibrosis. Cystic cells form excess centrosomes via a process termed centrosome amplification (CA), which often causes abnormal multipolar spindle configurations, mitotic catastrophe, and reduced cell viability. However, cells with CA can suppress multipolarity via “centrosome clustering”, a key mechanism by which cells circumvent apoptosis. Here, we demonstrate that inhibiting centrosome clustering can counteract the proliferation of renal cystic cells with high incidences of CA. Using ADPKD human cells and mouse models, we show that blocking centrosome clustering with two inhibitors, CCB02 and PJ34, blocks cyst initiation and growthin vitroandin vivo. Inhibition of centrosome clustering activates a p53-mediated mitotic surveillance mechanism leading to apoptosis, reduced cyst expansion, interstitial fibrosis, and improved kidney function. Transcriptional analysis of kidneys from treated mice identified pro-inflammatory signaling pathways implicated in CA-mediated cystogenesis and fibrosis. Our results provide the first evidence that centrosome clustering is a cyst-selective target for the improvement of renal morphology and function in ADPKD.

Background Origin, synthesis and activity of quinaldic acid (QA), proposed derivative of kynurenic acid, have been poorly studied to date. Previously, we have demonstrated the antiproliferative effect of QA in a colon cancer model in vitro. The goal of present study was to verify QA activity to modify the expression of p53 tumor suppressor in colon cancer cells, and to relate it to its cancer cell growth inhibiting activity in vitro. Methods LS180 colon cancer cells possessing the wild type form of p53 were used in the study. Real-time PCR and immunobloting techniques were used to test the expression of p53 at gene and protein level, respectively. Next, immunocytochemistry was used to visualize the localization of p53 protein within the cells. Furthermore, the antiproliferative activity of QA was retested in cells with siRNA silenced P53 gene. Results The activity of QA to modify both the expression and phosphorylation of p53 protein as well as the level of P53 gene is shown. Concomitantly, the nuclear and cytoplasmic localization of phospho-p53 protein upon QA treatment is also presented. Moreover, reduced activity of QA in colon cancer cells with silenced p53 expression is observed. Conclusion QA affects the expression of p53 tumor suppressor, both at gene and protein level. The prominent contribution of p53 to the antiproliferative effect of QA in LS180 colon cancer cells can be suggested.

The aim of the study was to investigate the anticancer potential of LY294002 (PI3K inhibitor) and temozolomide using glioblastoma multiforme (T98G) and anaplastic astrocytoma (MOGGCCM) cells. Apoptosis, autophagy, necrosis, and granules in the cytoplasm were identified microscopically (fluorescence and electron microscopes). The mitochondrial membrane potential was studied by flow cytometry. The activity of caspases 3, 8, and 9 and Akt was evaluated fluorometrically, while the expression of Beclin 1, PI3K, Akt, mTOR, caspase 12, and Hsp27 was determined by immunoblotting. SiRNA was used to block Hsp27 and PI3K expression. Cell migration and localization of Hsp27 were tested with the wound healing assay and immunocytochemistry, respectively. LY294002 effectively diminished the migratory potential and increased programmed death of T98G and MOGGCCM. Autophagy was dominant in MOGGCCM, while apoptosis was dominant in T98G. LY294002 with temozolomide did not potentiate cell death but redirected autophagy toward apoptosis, which was correlated with ER stress. A similar effect was observed after blocking PI3K expression with siRNA. Transfection with Hsp27 siRNA significantly increased apoptosis related to ER stress. Our results indicate that inhibition of the PI3K/Akt/mTOR pathway sensitizes glioma cells to apoptosis upon temozolomide treatment, which was correlated with ER stress. Hsp27 increases the resistance of glioma cells to cell death upon temozolomide treatment.

Tryptophan metabolites: kynurenine (KYN), kynurenic acid (KYNA) and 6-formylindolo[3,2-b]carbazole (FICZ) are considered aryl hydrocarbon receptor (AhR) ligands. AhR is mainly expressed in barrier tissues, including skin, and is involved in various physiological and pathological processes in skin. We studied the effect of KYN, KYNA and FICZ on melanocyte and melanoma A375 and RPMI7951 cell toxicity, proliferation and cell death. KYN and FICZ inhibited DNA synthesis in both melanoma cell lines, but RPMI7951 cells were more resistant to pharmacological treatment. Tested compounds were toxic to melanoma cells but not to normal human adult melanocytes. Changes in the protein level of cyclin D1, CDK4 and retinoblastoma tumor suppressor protein (Rb) phosphorylation revealed different mechanisms of action of individual AhR ligands. Importantly, all tryptophan metabolites induced necrosis, but only KYNA and FICZ promoted apoptosis in melanoma A375 cells. This effect was not observed in RPMI7951 cells. KYN, KYNA and FICZ in higher concentrations inhibited the protein level of AhR but did not affect the gene expression. To conclude, despite belonging to the group of AhR ligands, KYN, KYNA and FICZ exerted different effects on proliferation, toxicity and induction of cell death in melanoma cells in vitro.

8-Hydroxyquinaldic acid, the end-metabolite of tryptophan, is well-known metal chelator, however, its role in humans, especially in cancer promotion and progression, has not been fully revealed. Importantly, 8-hydroxyquinaldic acid is the analog of kynurenic acid with evidenced antiproliferative activity towards various cancer cells. In this study, we revealed that 8-hydroxyquinaldic acid inhibited not only proliferation and mitochondrial activity in colon cancer HT-29 and LS-180 cells, but it also decreased DNA synthesis up to 90.9% for HT-29 cells and 76.1% for LS-180 cells. 8-Hydroxyquinaldic acid induced changes in protein expression of cell cycle regulators (CDK4, CDK6, cyclin D1, cyclin E) and CDKs inhibitors (p21 Waf1/Cip1, p27 Kip1), but the effect was dependent on the tested cell line. Moreover, 8-hydroxyquinaldic acid inhibited migration of colon cancer HT-29 and LS-180 cells and increased the expression of &beta, catenin and E-cadherin. Importantly, antiproliferative and anti-migratory concentrations of 8-hydroxyquinaldic acid were non-toxic in vitro and in vivo. We reported for the first time antiproliferative and anti-migratory activity of 8-hydroxyquinaldic acid against colon cancer HT-29 and LS-180 cells.

In the recent years, coumarin bioactive compounds have been identified to posess anticancer properties. Therefore, the aim of the present study was to investigate for the first time the efficacy of osthole, umbelliferone, esculin, and 4-hydroxycoumarin, alone and in combination with Temozolomide, in the elimination of deadly brain tumors, anaplastic astrocytoma (AA) and glioblastoma multiforme (GBM) cells via programmed death. Our results indicated that osthole, umbelliferone, esculin, and 4-hydroxycoumarin initiated mainly apoptosis in the T98G and MOGGCCM cells. Osthole was the most effective. It also initiated autophagy in a small percentage of the cell population. The co-incubation with Temozolomide did not increase the pro-apoptotic potential of natural compounds but decreased the level of autophagy in the T98G cells. Apoptosis was associated with reduced mitochondrial membrane potential, activation of caspase 3, inhibition of Bcl-2 expression and the presence of a Bcl-2/Beclin 1. Blocking of Bcl-2 expression resulted in promotion of apoptosis, but not autophagy, in the MOGGCCM and T98G lines. It also sensitized astrocytoma cells, but not GBM, to the combined osthole and TMZ treatment, which was correlated with a reduced level of Beclin 1 and increased expression of caspase 3. Osthole and TMZ, alone and in combination, inhibited the migratory phenotype of the GBM and AA cells. In summary, our results indicated that osthole effectively eliminated glioma cells via apoptosis, what was correlated with Bcl-2/Beclin 1 complex formation. Considering the anti-migratory effect, osthole and Temozolomide display antiglioma potential but it needs further extensive studies.

Background Gliomas are aggressive brain tumors with very high resistance to chemotherapy. Therefore, the aim of the present study was to investigate the effectiveness of sorafenib and Temozolomide in elimination of human glioma cells through apoptosis and autophagy. Methods MOGGCCM (anaplastic astrocytoma) and T98G (glioblastoma multiforme) cell lines incubated with sorafenib and/or Temozolomide were used in the experiments. Cell morphology (ER stress, apoptosis, autophagy, and necrosis) was analyzed microscopically while apoptosis and mitochondrial membrane potential were assessed with flow cytometry. Beclin1, LC3, p62, Hsp27, and Hsp72 levels were analyzed by immunoblotting. The activity of caspase 3, 8, and 9 was evaluated fluorometrically. Expression of Hsps was blocked by transfection with specific siRNA. Results In MOGGCCM cells, Temozolomide most frequently induced autophagy, which was accompanied by decreased p62 and increased beclin1 and LC3II levels. Sorafenib initiated mainly apoptosis. Additional incubation with Temozolomide, synergistically potentiated the pro-apoptotic properties of sorafenib, but it was mediated in a caspase-independent way. In T98G cells, the effect of the analyzed drugs on programmed cell death induction was different from that in MOGGCCM cells. Sorafenib induced autophagy, while Temozolomide initiated mainly apoptosis. After simultaneous drug application, apoptosis dominated, suggesting synergistic action of both drugs. Inhibition of Hsp27 and Hsp72 expression increased the sensitivity of both cell lines to ER stress and, to a lesser extent, to induction of apoptosis, but not autophagy. Conclusions Sorafenib and Temozolomide applied in combination are potent apoptosis inducers in T98G and MOGGCCM cells. ER stress precedes the elimination. Blocking of Hsp expression has a greater impact on ER stress rather than apoptosis induction.

The treatment of epilepsy remains difficult mostly since almost 30% of patients suffer from pharmacoresistant forms of the disease. Therefore, there is an urgent need to search for new antiepileptic drug candidates. Previously, it has been shown that 4-alkyl-5-substituted-1,2,4-triazole-3-thione derivativatives possessed strong anticonvulsant activity in a maximal electroshock-induced seizure model of epilepsy. In this work, we examined the effect of the chemical structure of the 1,2,4-triazole-3-thione-based molecules on the anticonvulsant activity and the binding to voltage-gated sodium channels (VGSCs) and GABAA receptors. Docking simulations allowed us to determine the mode of interactions between the investigated compounds and binding cavity of the human VGSC. Selected compounds were also investigated in a panel of ADME-Tox assays, including parallel artificial membrane permeability assay (PAMPA), single cell gel electrophoresis (SCGE) and cytotoxicity evaluation in HepG2 cells. The obtained results indicated that unbranched alkyl chains, from butyl to hexyl, attached to 1,2,4-triazole core are essential both for good anticonvulsant activity and strong interactions with VGSCs. The combined in-vivo, in-vitro and in-silico studies emphasize 4-alkyl-5-substituted-1,2,4-triazole-3-thiones as promising agents in the development of new anticonvulsants.

Coumarins, which occur naturally in the plant kingdom, are diverse class of secondary metabolites. With their antiproliferative, chemopreventive and antiangiogenetic properties, they can be used in the treatment of cancer. Their therapeutic potential depends on the type and location of the attachment of substituents to the ring. Therefore, the aim of our study was to investigate the effect of simple coumarins (osthole, umbelliferone, esculin, and 4-hydroxycoumarin) combined with sorafenib (specific inhibitor of Raf (Rapidly Accelerated Fibrosarcoma) kinase) in programmed death induction in human glioblastoma multiforme (T98G) and anaplastic astrocytoma (MOGGCCM) cells lines. Osthole and umbelliferone were isolated from fruits: Mutellina purpurea L. and Heracleum leskowii L., respectively, while esculin and 4-hydroxycoumarin were purchased from Sigma Aldrich (St. Louis, MO, USA). Apoptosis, autophagy and necrosis were identified microscopically after straining with specific fluorochromes. The level of caspase 3, Beclin 1, PI3K (Phosphoinositide 3-kinase), and Raf kinases were estimated by immunoblotting. Transfection with specific siRNA (small interfering RNA) was used to block Bcl-2 (B-cell lymphoma 2), Raf, and PI3K expression. Cell migration was tested with the wound healing assay. The present study has shown that all the coumarins eliminated the MOGGCCM and T98G tumor cells mainly via apoptosis and, to a lesser extent, via autophagy. Osthole, which has an isoprenyl moiety, was shown to be the most effective compound. Sorafenib did not change the proapoptotic activity of this coumarin, however, it reduced the level of autophagy. At the molecular level, the induction of apoptosis was associated with a decrease in the expression of PI3K and Raf kinases, whereas an increase in the level of Beclin 1 was observed in the case of autophagy. Inhibition of the expression of this protein by specific siRNA eliminated autophagy. Moreover, the blocking of the expression of Bcl-2 and PI3K significantly increased the level of apoptosis. Osthole and sorafenib successfully inhibited the migration of the MOGGCCM and T98G cells.

Lycopene, sulforaphane, quercetin, and curcumin, ingredients of daily diet, show significant anticancer and chemopreventive potential; however, no data are available showing thorough evaluation of jointly used phytochemicals on cancer cell proliferation. Here, we compare anticancer potential of mentioned substances applied separately or in combination (as MIX) by measuring mitochondrial activity (MTT test), DNA synthesis (BrdU test) and lactate dehydrogenase release (LDH test) in colon epithelial (CCD841 CoTr), and colon cancer (HT-29, LS174T) cells. Additive inhibitory effect of simultaneously used phytochemicals on cancer cells proliferation has been shown. In epithelial cells, tested combination effectively inhibited mitochondrial activity, but not DNA synthesis. LDH test revealed cytotoxicity of tested mixture against cancer cells without negative effect on normal cells. Furthermore, we demonstrated that MIX enhances antiproliferative effect of common cytostatics: 5-fluorouracil and cisplatin. Presented data suggest chemopreventive potential of the proposed combination of natural substances and their usefulness as adjuvant strategy during chemotherapy. PRACTICAL APPLICATIONS: Colorectal cancer is one of the most common causes of cancer death worldwide. Since its development and progression is strongly correlated with dietary habits, healthy diet as well as supplementation with proved anticancer agents seems to be reasonable strategy of colon cancer prevention and treatment. In the present study, we have focused on four natural compounds abundantly found in daily diet i.e., lycopene, sulforaphane, quercetin, and curcumin, with well established anticancer potential. Their individual and collective impact both on normal colon epithelium cells and colon cancer cells viability, growth, and proliferation was examined. Furthermore, activity of the substances combined as MIX to influence antiproliferative potential of commonly used in colon cancer treatment cytostatics, 5-fluorouracil, and cisplatin was verified. Proposed in the study combination of phytochemicals with experimentally proven antiproliferative activity may propose an effective strategy for prevention and treatment of colon cancer.

A new one-step synthesis of novel biologically active 2-substituted 2,4-dihydroxyphenyl-4 $$H$$ -thieno[3,2- $$d$$ ][1,3]thiazin-4-ones and 4 $$H$$ -thieno[2,3- $$d$$ ][1,3]thiazin-4-ones has been elaborated and described. The compounds were prepared by the reaction of aryl-modified sulfinylbis [(2,4-dihydroxyphenyl)methanethione]s and the corresponding aminothiophenecarboxamides. The derivatives showed anticancer activity in vitro. These compounds inhibited the proliferation and viability of lung cancer A549, colon cancer HT-29 and glioma C6 cells in a concentration-dependent manner. Some of the derivatives had no influence on normal skin fibroblasts culture viability. Moreover, one compound (1b) showed the ability to inhibit DNA synthesis in cancer cells, especially in C6 cells, and was not toxic for normal oligodendrocytes and hepatocytes. Using reversed phase RP 18 HPLC and immobilised artificial membrane (IAM) chromatography the phase affinity of the compounds was determined. The influence of lipophilicity on the activity of compounds has been discussed.

We reported the synthesis and characterization of a series of azolo- and azino[1,3]thiazinones containing the 2,4-dihydroxyphenyl substituent. The compounds were prepared by a new one-step reaction of aryl-modified sulfinylbis[(2,4-dihydroxyphenyl)methanethione]s and the corresponding aminoazolo(azino)carboxamides. Their chemical structures were confirmed by IR, NMR: 1H, 13C, HSQC, and EI-MS spectral data. The compounds inhibited proliferation and viability of lung cancer A549, colon cancer HT-29, and glioma C6 cells in a structure- and concentration-dependent manner. The activity of some analogues was below 10 μmol dm−3 (IC50). Glioma C6 cells were the most sensitive to tested compounds. Generally, the derivatives were not toxic for the skin fibroblast HSF culture. Moreover, some of them exerted a protective effect on the treated normal cells. Evaluation of compound properties in silico showed that they possess significant drug-like characteristics and most of them display a low toxicity. Graphical abstract

Background Previously, we have demonstrated that kynurenic acid (KYNA), an endogenous metabolite of tryptophan formed along kynurenine pathway, is present in synovial fluid of rheumatoid arthritis (RA) and osteoarthritis (OA) patients. In this study, the goal was to investigate the presence of quinaldic acid (QUDA), a putative metabolite of KYNA, in synovial fluid of RA and OA patients. Methods The effect of QUDA on proliferation and motility of synovial fibroblasts and its interaction with KYNA were determined in vitro. The study was conducted on synovial fluid obtained from 38 patients with RA and 15 patients with OA. QUDA was identified and quantified using the gas chromatography–mass spectrometry (GC–MS) method. In vitro experiments were conducted on rabbit synoviocyte cell line HIG-82. Results Presence of QUDA was detected in all 53 samples of synovial fluid. The concentration of QUDA in synovial fluid obtained from patients with RA was 28.6 ± 14.9 pmol/ml, which was lower in comparison with OA 42.3 ± 10.0 pmol/ml. QUDA content positively correlated with the number of tender joints and negatively with the total cell counts determined in synovial fluid of RA patients. It did not correlate with KYNA content. QUDA reduced both proliferation and motility of synoviocytes in a dose-dependent manner. The enhancement of antiproliferative action of QUDA by KYNA was evidenced. Conclusions Data show a local deficit of QUDA in RA patients and suggest its potential role as an endogenous substance controlling synoviocyte viability.

The aim of the present study was to investigate the effect of sorafenib and quercetin on the induction of apoptosis and autophagy in human anaplastic astrocytoma (MOGGCCM) and glioblastoma multiforme (T98G) cell lines. In MOGGCCM cells, sorafenib initiated mainly apoptosis, mediated by the mitochondrial pathway with mitochondrial membrane permeabilization, cytochrome c release to the cytoplasm, and activation of caspase 9 and 3. Additional incubation with quercetin potentiated the pro-apoptotic properties of sorafenib. In T98G cells, autophagy was observed most frequently after the sorafenib treatment. It was accompanied by increased beclin 1 and LC3II expression. Administration of quercetin after the sorafenib treatment resulted in an increased number of autophagic cells. After simultaneous drug application, the level of autophagy was lower in favour of apoptosis. Inhibition of heat shock proteins expression by specific small interfering RNA significantly increased the sensitivity of both the cell lines to induction of apoptosis, but not autophagy. We demonstrated for the first time that sorafenib and quercetin are very effective programmed cell death inducers in T98G and MOGGCCM cells, especially in cells with blocked expression of heat shock proteins.

The aim of the present study was to investigate whether silencing of Hsp27 or Hsp72 expression in glioblastoma multiforme T98G and anaplastic astrocytoma MOGGCCM cells increases their sensitivity to programmed cell death induction upon temozolomide and/or quercetin treatment. Transfection with specific siRNA was performed for the Hsp gene silencing. As revealed by microscopic observation and flow cytometry, the inhibition of Hsp expression was correlated with severe apoptosis induction upon the drug treatment studied. No signs of autophagy were detected. This was correlated with a decreased mitochondrial membrane potential, increased level of cytochrome c in the cytoplasm, and activation of caspase 3 and caspase 9. All these results suggest that the apoptotic signal was mediated by an internal pathway. Additionally, in a large percentage of cells treated with temozolomide, with or without quercetin, granules within the ER system were found, which was accompanied by an increased level of caspase 12 expression. This might be correlated with ER stress. Quercetin and temozolomide also changed the shape of nuclei from circular to "croissant like" in both transfected cell lines. Our results indicate that blocking of Hsp27 and Hsp72 expression makes T98G cells and MOGGCCM cells extremely vulnerable to apoptosis induction upon temozolomide and quercetin treatment and that programmed cell death is initiated by an internal signal.

Melanoidins are brown, nitrogen containing, high molecular weight end products of Maillard reaction with poorly established activity towards tumor cells. The goal of present study was to verify whether both heated potato fiber Potex extract (180°C for 2h) and melanoidins isolated from the extract exerts growth-inhibiting activity in human colon cancer cells in vitro. The cells of LS180 colon cancer cell line were tested upon treatment with roasted potato fiber extract (AM4) as well as with high (HMW) and low (LMW) molecular weight fractions isolated from the extract, since both may be regarded as/or contain melanoidins. The tested compounds at concentration of 1000 μg/ml reduced cell growth down to 45%, 69% and 54%, respectively. Furthermore, deregulated ERK1/2 signaling was revealed upon treatment. Moreover, multiple alternations in cell cycle regulators activity were found (i.e. cyclinD1, cyclin-dependent kinase 4 and 6, p21, p27, p53, pRb) leading to cell cycle cessation in G0 phase. Importantly, LMW compounds revealed markedly stronger potential to alter specific molecular targets comparing to HMW compounds. Summarizing, the results emphasize that both high and low molecular weight melanoidins contribute to antiproliferative activity of heated potato fiber in LS180 colon cancer cells in vitro.

Melanoidins are brown, high molecular weight products of Maillard reaction, which takes place during thermal processing of food. They are formed in a multistage reaction between reducing sugars and compounds possessing free amino groups and found in roasted coffee, bakery products, cooked meat, beer, honey, sweet wine, processed tomatoes, and fiber. Nowadays, melanoidins have attracted a lot of attention, not only as a functional food ingredient, but also as a potential pro-healthy dietary supplement. In this field, their antioxidant, antimicrobial, anticancer, and detoxifying activity have been described. Based on recent research developments, an overview of the biological properties of melanoidins with implications for human health is presented.

Glioblastoma multiforme is the most aggressive primary brain tumour. At the cellular and molecular levels, several mechanisms responsible for apoptosis or autophagy induction are blocked. Identification of molecular targets stimulating cells to initiate programmed cell death should be performed for therapeutic purposes. A promising solution is the combination of temozolomide and quercetin. The aim of our study was to evaluate the effect of both drugs, applied alone and in combinations, on apoptosis and autophagy induction in human glioblastoma multiforme T98G cells. Our results clearly indicate that quercetin and temozolomide induce apoptosis very significantly, having no effect on autophagy induction. At the molecular level, it was correlated with caspase 3 and 9 activation, cytochrome c release from the mitochondrium and a decrease in the mitochondrial membrane potential. Both drugs are also potent Hsp27 and Hsp72 inhibitors. This suggests that the apoptotic signal goes through an internal pathway. Increased expression of caspase 12 and the presence of several granules in the cytoplasm after temozolomide treatment with or without quercetin preceding appearance of apoptosis may suggest that apoptosis is initiated by ER stress. Additionally, it was accompanied by changes in the nuclear morphology from circular to ‘croissant like’.

Alpha-ketoglutarate (AKG), a key intermediate in Krebs cycle, is an important biological compound involved in the formation of amino acids, nitrogen transport, and oxidation reactions. AKG is already commercially available as a dietary supplement and its supplementation with glutamine, arginine, or ornithine alpha-ketoglutarate has been recently considered to improve anticancer immune functions. It is well documented that AKG treatment of Hep3B hepatoma cells in hypoxia induced HIF-alpha (hypoxia-inducible factor) degradation and reduced vascular endothelial growth factor (VEGF) synthesis. Moreover, AKG showed potent antitumor effects in murine tumor xenograft model, inhibiting tumor growth, angiogenesis, and VEGF gene expression. However, the mechanisms of its anticancer activity in normoxia have not been examined so far.Here, we report that in normoxia, AKG inhibited proliferation of colon adenocarcinoma cell lines: Caco-2, HT-29, and LS-180, representing different stages of colon carcinogenesis. Furthermore, AKG influenced the cell cycle, enhancing the expression of the inhibitors of cyclin-dependent kinases p21 Waf1/Cip1 and p27 Kip1. Moreover, expression of cyclin D1, required in G1/S transmission, was decreased, which accompanied with the significant increase in cell number in G1 phase. AKG affected also one the key cell cycle regulator, Rb, and reduced its activation status.In this study for the first time, the antiproliferative activity of AKG on colon adenocarcinoma Caco-2, HT-29, and LS-180 cells in normoxic conditions was revealed. Taking into consideration an anticancer activity both in hypoxic and normoxic conditions, AKG may be considered as a new potent chemopreventive agent.

The molecular chaperone Hsp90 cooperates with multiple cochaperone proteins as it promotes the folding and activation of diverse client proteins. Some cochaperones regulate the ATPase activity of Hsp90, while others appear to promote Hsp90 interaction with specific types of client proteins. Through its interaction with the adenylate cyclase Cyr1, the Sgt1 cochaperone modulates the activity of the cAMP pathway in Saccharomyces cerevisiae. A specific mutation in yeast Hsp90, hsc82-W296A, or a mutation in Sgt1, sgt1-K360E, resulted in altered transcription patterns genetically linked to the cAMP pathway. Hsp90 interacted with Cyr1 in vivo and the hsc82-W296A mutation resulted in reduced accumulation of Cyr1. Hsp90-Sgt1 interaction was altered by either the hsc82-W296A or sgt1-K360E mutation, suggesting defective Hsp90-Sgt1 cooperation leads to reduced Cyr1 activity. Microarray analysis of hsc82-W296A cells indicated that over 80 % of all transcriptional changes in this strain may be attributed to altered cAMP signaling. This suggests that a majority of the cellular defects observed in hsc82-W296A cells are due to altered interaction with one specific essential cochaperone, Sgt1 and one essential client, Cyr1. Together our results indicate that specific interaction of Hsp90 and Sgt1 with Cyr1 plays a key role in regulating gene expression, including genes involved in polarized morphogenesis.

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.

Potex constitutes a potato fiber preparation widely used as an ingredient to meat and bakery products which thermal treatment results in creation of new compounds. Melanoidins are high molecular weight brown end products of Maillard reaction, and few data presenting tumor cell growth inhibiting activity of melanoidins have been reported. Thus, in present study we utilized water extract of Potex roasted (180 °C for 2 h), whose chemical characterization revealed the presence of melanoidin complexes. Heated Potex extract inhibited C6 glioma cell proliferation in a dose-dependent manner measured by MTT method. High molecular weight components present in initial extract were responsible for stronger antiproliferative effect compared with low molecular weight fraction. Impaired MAPK (mitogen-activated protein kinase) and Akt signaling was found in cells treated with the extract. Moreover, flow cytometry analyses revealed the extract to induce G1/S arrest in glioma cells. Simultaneously, Western blot analysis showed elevated levels of p21 protein with concomitant decrease of cyclin D1. In conclusion, observed antiproliferative activity of melanoidins present in heated Potex was linked to disregulated MAPK and Akt signaling pathways, as well as to cell cycle cessation. These results suggest potential application of Potex preparation as a functional food ingredient and chemopreventive agent.

The medicinal mushroom Chaga, Inonotus obliquus (Pers.:Fr.) Pilát (Hymenochaetaceae), has been used in folk medicine in Russia, Poland, and most of the Baltic countries, as a cleansing and disinfecting measure, and as decoctions for stomach diseases, intestinal worms, liver and heart ailments, and cancer treatment. Many reports have been published concerning the health promoting functions of this mushroom, including antibacterial, hepatoprotective, anti-inflammatory, antitumor, and antioxidant activities. The purpose of the present study was evaluation of in vitro anticancer activity of fraction IO4 isolated from I. obliquus. The effect on cell proliferation, motility and viability was assessed in a range of cancer and normal cells. Chaga fraction prepared from dried fruiting bodies was subjected to anticancer evaluation in human lung carcinoma (A549), colon adenocarcinoma (HT-29), and rat glioma (C6) cell cultures. Human skin fibroblasts (HSF), bovine aorta endothelial cells (BAEC), models of rat oligodendrocytes (OLN-93), hepatocytes (Fao), rat astroglia, and mouse neurons (P19) were applied to test toxicity in normal cells. The following methods were applied: tumor cell proliferation (MTT assay and BrdU assay), cytotoxicity (LDH assay), tumor cell motility (wound assay), tumor cell morphology (May-Grünwald-Giemsa staining), and death detection (ELISA). Chaga fraction elicited anticancer effects which were attributed to decreased tumor cell proliferation, motility and morphological changes induction. Of note is the fact that it produced no or low toxicity in tested normal cells. The data presented could open interesting paths for further investigations of fraction IO4 as a potential anticancer agent.

gene expression hadthe tendency to longer survival in all Dukes’ stages.Loss of mismatch repair (MMR) function is implicatedin the phenomena of microsatellite instability (MSI), whichis characterized by the accumulation of somatic alterationin the length of simple, repeated sequences; microsatellites(Ahmed 2003). MSI has been identified in tumours of hered-itary non-polyposis colorectal cancer (HNPCC) colorectalcancer and sporadic colorectal cancer, where it occurs in 10–15% of the cases (Gryfe

2-(2,4-Dihydroxyphenyl)thieno-1,3-thiazin-4-ones are a group of new compounds with potential anticancer activity. This type of derivatives was poorly investigated in the area of synthesis and biological activities. In the present study the antiproliferative action of the most active derivative BChTT was described. The aim of biological evaluation was to investigate the ability of the compound to inhibit cancer cell proliferation and identify mechanism involved in its action on the molecular level. BChTT inhibited the proliferation of lung cancer A549, colon cancer HT-29 and glioma C6 cells in the concentration-dependent manner. It was not toxic to normal cells including skin fibroblasts, hepatocytes and oligodendrocytes in the antiproliferative concentrations. BChTT decreased the DNA synthesis in the treated cancer cells and induced cell cycle arrest in the G0/G1 phase. Moreover, the ability of the compound to activate p38 kinase and decrease cyclin D1 expression was estimated. Participation of p38 kinase in the antiproliferative action of the compound was confirmed by the analysis of BChTT activity in the cells with the p38 silenced gene. The obtained results may suggest the ability of the tested derivative to inhibit cancer cells proliferation by induction of p38-mediated cyclin D1 downregulation.

Quinaldic acid is presumed to be a derivative of kynurenic acid, a tryptophan metabolite with proven antiproliferative activity towards cancer cells in vitro. The aim of present study was to evaluate the activity of quinaldic acid in colon cancer cells. The antiproliferative potential of quinaldic acid was assessed in HT-29, LS180 and Caco-2 cells. Suppression of metabolic activity (IC50 of 0.5mM for HT-29 and LS180 cells, 0.9mM for Caco-2 cells) and DNA synthesis (IC50 of 2.7, 4.3, 2mM for HT-29, LS180 and Caco-2 cells, respectively) were observed in all tested cell lines. It is noteworthy that quinaldic acid in antiproliferative concentrations was non-toxic to normal colon epithelium CCD 841 CoTr cells. Concomitantly, alterations in several signaling pathways in HT-29 cells were observed. Quinaldic acid led to changes in the phosphorylation level of extracellular-signal-regulated kinase (ERK) 1/2, p38, cAMP response element-binding protein (CREB) and Akt (protein kinase B) kinases. Moreover, changes in the CREB transcription factor were also found at the gene expression level. Antiproliferative activity and signaling pathways modulatory potential of quinaldic acid in colon cancer cells in vitro has been stated.

4BrABT (2-(4-Bromophenylamino)-5-(2,4-dihydroxyphenyl)-1,3,4-thiadiazole) is a compound known for its interesting in vitro anticancer profile. 4BrABT inhibited proliferation and motility of several cancer cell lines in concentrations which were not toxic to normal cells. A major problem associated with cancer chemotherapy, but also caused by environmental factors such as pesticides, is neurotoxicity. Therefore, the aim of the presented study was an in vitro evaluation of the neuroprotective activity of this compound. 4BrABT activity (1-100 μM) was tested in cultures of mouse neurons, rat astrocytes and rat oligodendrocytes. A possible protective action of the compound in different neurodegenerative models, as serum deprivation (SD), excitotoxicity (presence of 500 μM glutamate in culture medium), as well as cisplatin toxicity (astroglia--50 μM and oligodendroglia--100 μM) was investigated. Cell viability in the tested cultures was assessed with the use of LDH and MTT methods. Moreover, 4BrABT ability to prevent the cisplatin-induced apoptosis in astrocyte and oligodendrocyte cultures was analysed after Hoechst 33342 fluorostaining. The obtained results indicate that 4BrABT was not toxic to neurons, astrocytes and oligodendrocytes. Moreover, a decrease in the neuronal LDH level was observed, which may suggest the ability of 4BrABT to act as a trophic agent. Furthermore, the protective action of the studied compound was shown in neuronal cultures exposed to neurotoxic conditions (presence of glutamate and trophic stress) and in cisplatin-treated astrocytes and oligodendrocytes. The expression of anticancer and neuroprotective activity raises hopes for the potential use of 4BrABT as a safe anticancer drug, or neuroprotective agent in chemotherapy-associated neurotoxicity.

A foreign body in the rectum is not a very common emergency case in surgical practice, of various etiology. In the years 2003-2011, 8 people were hospitalised in the Clinic of General and Colorectal Surgery due to a foreign body in the rectum. All the patients were male. All of them were qualified for foreign body removal in a surgical suite, under general anaesthesia due to a potential need for expanding the scope of the procedure. In all situations attempts were made at removing the object through the anus, which proved successful in 7 cases, without complications.In one case the scope of the procedure needed to be expanded with laparotomy and sigmoidotomy, through which the foreign body was removed. This procedure was also carried out with no complications.

Background High expression of HSP27 and HSP72 in glioma cells has been closely associated with chemoresistance and decreased sensitivity to programmed cell death induction. Therefore, it is important to devise therapies that effectively target invasive cancer cells by inducing cell death. The aim of our study was to assess the effect of quercetin and imperatorin applied separately and in combinations on the apoptosis and autophagy induction in human T98G cells cultured in vitro . Methods Cell death induction was analyzed by the staining method. The Western blotting technique and fluorimetric measurements of activity were used to assess the expression of marker proteins of apoptosis and autophagy. The specific siRNA transfected method was used for blocking of the expression of HSP27 and HSP72 genes. Results The experiments revealed the highest percentage of apoptotic cells after using a 50 μM concentration of both compounds. Simultaneous quercetin and imperatorin administration induced apoptosis more effectively than incubation with single drugs. These results were accompanied with decreased HSP27 and HSP72 expression, and a high level of caspase-3 and capsae-9 activity. Autophagy was not observed. Additional experiments were performed on a cell line with blocked Hsp27 and Hsp72 expression and significant increase the sensitivity to apoptosis induction upon quercetin and imperatorin treatment was noticed. Conclusions The present study indicates that quercetin and imperatorin are potent apoptosis inducers, especially when they act synergistically, which may be a promising combination useful in glioma therapy. Our results also demonstrated that blocking the HSP27 and HSP72 gene expression might serve as a therapeutic target for the human brain cancer.

Growth of human leiomyomas can probably be initiated as a response to injury, in a way similar to the development of keloids. Among many bioactive molecules, which are implicated in tissue repair, a pivotal role is attributed to matricellular proteins. The aim of the current study was to evaluate the immunohistochemical expression of tenascin-C (TNC), thrombospondin-1 (TSP-1), SPARC/osteonectin and tenascin-X (TNX) in human uterine leiomyomas and normal myometrium. Immunostaining was performed on 33 pairs of paraffin-fixed sections and 9 cell-lines derived from uterine leiomyomas and normal myometrium. Fifteen (45.5%) leiomyomas investigated were positive for TNC, whereas all normal myometrial samples were immunonegative (χ²=19.41; p0.001). Immunostaining for TSP-1 was observed in 20 (60.6%) uterine fibroids and in 12 (36.4%) control samples (χ²=3.88; p0.05). The expression of SPARC/osteonectin protein was more frequently found in leiomyomas than in normal myometrium, but this difference was not significant. Apart from one fibroid culture and one myometrial culture, all the others revealed strong TNC immunostaining. Expression of TSP-1 and SPARC/osteonectin was weak to moderate in all established cell-lines. None of the tissues or cell lines investigated showed positive staining for TNX. In conclusion, TSP-1 and TNC are likely to play important roles in the pathogenesis of uterine leiomyomas, presumably affecting cell proliferation and/or extracellular matrix deposition.

Kynurenic acid (KYNA), a tryptophan metabolite, was found in human saliva, gastric juice, bile, pancreatic juice and mucus of rat small intestine.KYNA content in mucus aspirated from human caecum or colon ascendens and KYNA production in colon epithelial and cancer cells were determined using HPLC. Moreover, biological properties of KYNA and kynurenine aminotransferases (KATs) expression in colon epithelial and colon cancer cells were studied.Considerably higher KYNA concentration was detected in samples from patients diagnosed with colon carcinoma (269.40 ± 107.00 pmol/ml, N = 4), Adenoma tubulovillosum (200.50 ± 36.72, N = 10) or Adenoma tubulare (243.50 ± 38.09, N = 9) than in control group (82.22 ± 7.61 pmol/ml, N = 30). Moreover, colon epithelium CCD 841 CoTr cells actively synthesized KYNA in a concentration- and time-dependent manner. This process was decreased by aminooxyacetic acid and L-glutamate in opposite to 4-aminopyridine treatment. Interestingly, KYNA production in colon cancer cells (HT-29 1.39 ± 0.27, LS-180 1.18 ± 0.15 and Caco-2 4.21 ± 0.30 pmol/1 x 10(5) cells/2 h) was considerably higher in comparison to normal colon epithelial cells (0.70 ± 0.07 pmol/1 x 10(5) cells/2 h). However, KATs I and II were expressed at similar level in both colon epithelium and cancer cells. Furthermore, KYNA exerted an antiproliferative effect at higher micro- and millimolar concentrations against colon cancer cells with the IC(50) of 0.9, 0.2 and 1.2 mM for HT-29, LS-180 and Caco-2 cells, respectively.Summarizing, this is the first report presenting KYNA synthesis and KAT expression in colon derived normal and cancer cells.

Cancer chemoprevention is defined as the application of natural or synthetic agents to suppress or reverse cancer development and progression. In this field especially diet derived compounds have recently attracted researchers’ attention as potential therapeutics generally exerting low toxicity compared with regular drugs. This review presents a survey of recent findings concerning the most promising dietary chemopreventive agents such as green tea polyphenols (i.e. catechins), long-chain polyunsaturated fatty acids, carotenoids, glucosinolates/isothiocyanates, vitamins (i.e. vitamin D and folate) and minerals (i.e. calcium and selenium). Molecular targets involved in intrinsic pathways affected by these natural compounds are also shortly discussed.

UNLABELLED Endoscopic polypectomy of colorectal polyps is a common procedure. However, endoscopic treatment of large polyps (those with a diameter exceeding 2 cm) remains questionable. There is a serious risk of colorectal carcinoma presence inside these lesions, which eventually would require surgical intervention. Apart from this fact endoscopic polypectomy of large polyps is connected with substantial risk of complications, such as perforation and bleeding. Many patients with large colorectal polyps are qualified for surgical intervention. THE AIM OF THE STUDY was to determine the efficacy and safety of polypectomy of large colorectal polyps. MATERIAL AND METHODS The study presented results of endoscopic treatment in case of patients with large colorectal polyps at the Department of General and Colorectal Surgery, Medical University in Łodź. Patients were admitted to the hospital during the period between January, 2008 and January, 2010. The following parameters were analysed: location of polyps, percentage of high grade dysplasia, complete excision rate, and complications connected with polypectomy procedures. RESULTS During the analyzed period of time 488 endoscopic polypectomies were performed. Forty-three large colorectal polyps were removed (8.8%). Seven (16.3%) of them were classified as flat polyps. Out of 488 removed polyps, 39 were classified as adenomas with high grade dysplasia (7.9%), while 16 were large-exceeding 2 cm (37.2%). Considering the group of large polyps no invasive carcinoma case was detected. The radical excision rate for large pedunculated polyps was obtained in 88.8% (32/36) of cases. In case of flat adenomas the above-mentioned parameter was lower--57.1% (4/7). During polypectomy of large colorectal polyps one perforation was observed during the excision of a flat cecal polyp. In two cases immediate bleeding occurred (2/43). In both cases endoscopic treatment of bleeding proved sufficient. CONCLUSIONS Endoscopic polypectomy of large pedunculated polyps is a safe and efficient method, which makes it a rationale alternative for surgery. Polypectomy of flat adenomas is connected with a lower radical excision rate and higher risk of perforation.

Aqueous extract of Inonotus obliquus was hydrolyzed in dilute hydrochloric acid. The products were extracted applying organic solvents, and separated chromatographically on a silica gel-packed column. Eluted fractions were analyzed by means of GC-MS. The presence of hydrocarbons, alcohols, phenols and various carbonyl compounds in analyzed fractions has been detected and quantified. Preliminarily experiments on the influence of certain separated samples on the proliferation of A549 human lung carcinoma cells were performed. Therefore, we hypothesize that the major antiproliferative effects are related to the presence of benzaldehyde, which is a benzyl alcohol metabolite formed in situ in the cells culture with the yield moderated by the presence of trace amounts of "high molecular mass compounds".

The aim of the present study was to investigate the effect of Temozolomide (an alkylating chemotherapeutic agent) and quercetin (natural flavonoid) on cell death in the human astrocytoma cell line MOGGCCM (WHO grade III). Our results indicate that Temozolomide induces autophagy, while quercetin promotes severe necrosis in the cell line in a manner dependent on the drug concentration. We demonstrated for the first time that combinations of both drugs were much more effective in programmed cell death induction in glioma cells. At a low (5 μM) drug concentration, quercetin potentiated a pro-autophagic effect of Temozolomide, while after treatment with a higher drug concentration (30 μM), autophagy switched to apoptosis. Temozolomide attenuated the toxic effect of quercetin. Apoptosis was mediated by the mitochondrial pathway and the activation of caspase 3 and cytochrome C release, but no changes in caspase 8 expression was observed. It was accompanied by decreased mitochondrial membrane potential and inhibition of Hsp27 and Hsp72 expression. Autophagy was correlated with an increased level of LC3II. Temozolomide and quercetin also inhibited migratory phenotype of MOGGCCM cells and changed the nuclei morphology from a circular to an irregular shape. Our results indicate that quercetin acts in synergy with Temozolomide and when used in combination rather than in separate pharmacological application, both drugs are more effective in programmed cell death induction. Temozolomide administered with quercetin seems to be a potent and promising combination which might be useful in glioma therapy.

The aim of the present study was to investigate the kinetics of the effects exerted by Temodal and quercetin on the survival of the human astrocytoma MOGGCCM cell line. Our results indicate that quercetin was toxic and induced necrosis, whereas Temodal induced autophagy-mediated cell death most effectively. The amount of cell death directly correlated with drug concentration and length of exposure. During combined administration of both drugs, Temodal attenuated the cytotoxic effects of quercetin. Combinations of both drugs were effective in inducing programmed cell death, but the type of cell death was concentration-dependent. Coadministration of Temodal (100 µM) with a low quercetin concentration (5 µM) resulted in a very significant induction of autophagy; however, after treatment with quercetin at a higher concentration (30 µM), apoptosis became the primary mechanism of cell death. The sequence of drug administration was also important. The highest number of dead cells was observed after simultaneous administration of both drugs or after pre-incubation with Temodal followed by treatment with quercetin. Apoptosis was identified through activation of the mitochondrial pathway including cleavage of caspase-3 and release of cytochrome c. Autophagy was identified through increased levels of LC3II. Our results indicate that Temodal and quercetin are synergistic inducers of programmed cell death, better together than applied separately. This drug combination appears to be a potent and promising therapeutic relevant to the treatment of gliomas.

It is well known that the basis of antitumor activity of compounds is the induction of programmed cell death. At the base of this process is the activation and proper localization of marker proteins. Therefore, the aim of our studies was to determine the effect of quercetin and Temozolomide, used separately or in combinations on the localization of proapoptotic proteins such as cytochrome c, caspase-3, caspase-8, antiapoptotic Hsp27, Hsp72 and proautophagal LC3 in MOG-GCCM, human Anaplastic astrocytoma cell line.Incubation with quercetin stimulated the translocation of caspase-3 and Hsp72 from the cytoplasm to the nucleus. Temozolomide changed the localization of caspase-3 and Hsp72, causing migration of this protein from the cytoplasm to the nuclei. In the Temozolomide-treated cells caspase-8 was detected mainly in the cytoplasm. Quercetin and Temozolomide administered in combination caused changes in the distribution of tested proteins. Cells treatment with both drugs showed cytoplasmic localization of caspase-8 and nuclear localization of cytochrome c. In cells incubated with quercetin and Temozolomide Hsp27 was detected in the whole cell. In the case of cytoplasmic LC3 we did not notice any significant changes in distribution.

Microsatellite instability (MSI) is due to defective DNA mismatch repair and is characteristic of HNPCC tumours.The role of MSI in familial predisposition to colorectal cancer was investigated in this study by microsatellite analysis among familial cases.PCR-based microsatellite analysis was performed in blood obtained from 30 members from HNPCC families. Blood samples age matched healthy individuals (n = 28) served as control. MSI was studied at five loci containing single- or dinucleotide repeat sequences and mapping to different chromosomal locations: BAT-25 (at locus 4q12), BAT-26 (2p16), D2S123 (2p16-p21), D5S346 (5q21-q22) and D17S250 (17q11.2-q12).MSI frequency was higher in member of HNPCC families (40%) than in control (10.7%) cases. Out of the 30 samples tested, 12 were found to be MSI positive, 9 MSI high and 3 MSI low.The present study suggest that microsatellite instability seem to be a risk factor of colorectal cancer in subjects belonged to HNPCC families with high incidence of this cancer.

Susceptibility to colorectal cancer appears to be linked to germ-line mutations in genes causing various familial cancer syndromes. The objectives of this study were to determine microsatellite instability and the frequency of BRCA1 germ-line mutations in patients with family history of cancer. The study population consisted of 30 patients from HNPCC family. Patients completed a family history questionnaire and provided blood for mutation analysis. Seven out of 30 investigated samples (23%) were found to be MSI-positive, 6 MSI-high and 1 MSI-low. Ex20insC and ExII17delA mutations of BRCA1 gene were identified in MSI-positive samples from HNPCC families. In the present study one Ex20insC mutation and two ExII17delA mutations were detected only in MSI-high samples. Genetic alterations seem to be a risk factor of colorectal cancer in subjects belonging to HNPCC families with high incidence of this cancer. The lack of detectable germ-line mutations in most cases suggests that there are probably additional, as yet unidentified genes predisposing to this disease.

Microsatellite instability (MSI) is due to defective DNA mismatch repair (MMR) and is characteristic of hereditary nonpolyposis colorectal cancer (HNPCC) tumors. The role of MSI in familial predisposition to colorectal cancer was investigated in this study by both microsatellite analysis and mutation screening of the two major MMR genes MLH1 and MSH2 among familial cases.PCR-based microsatellite analysis was performed in blood obtained from 30 members from HNPCC families. Blood samples age matched healthy individuals (n = 28) served as control. MSI was studied at five loci containing single- or dinucleotide repeat sequences and mapping to different chromosomal locations: BAT-25 (at locus 4q12), BAT-26 (2p16), D2S123 (2p16-p21), D5S346 (5q21-q22) and D17S250 (17q11.2-q12).MSI frequency was higher in member of HNPCC families [7/30 (23%)] than in control [3/28 (10.7%)] cases. Two MLH1 and one MSH2 mutations were identified in 7 MSI positive samples from HNPCC families. MLH1/MSH2 mutations were only in MSI high samples detected.Genetic alterations seem to be a risk factor of colorectal cancer in subjects belonged to HNPCC families with high incidence of this cancer.

Quinaldic acid is naturally occurring in the human organism analog of endogenous tryptophan metabolite kynurenic acid, with not fully elucidated impact on endogenous physiological processes. Considering high level of structural similarity between quinaldic acid and kynurenic acid, which antiproliferative activity towards colon and renal cancer cells was already stated, and its presence in the human organism, evaluation of their chemopreventive potential seems to be a priority. We reported for the first time that in higher milimolar concentrations quinaldic acid possessed antiproliferative activity against colon adenocarcinoma HT-29 and LS-180 cells with the IC50 of 0.5 mM. Moreover, it inhibited DNA synthesis in both cell lines (HT-29, IC50 = 2.7 mM; LS-180, IC50 = 4.3 mM). Morphological changes in colon cancer cells exposed to quinaldic acid were also observed. Western blot analysis revealed that molecular mechanism of antiproliferative action might be based on strict control of the expression and activation of signaling kinases. Summarizing, although biological function of quinaldic acid in colon has still not been fully elucidated, it may be a potential agents in colon cancer chemoprevention.

Kynurenic acid (KYNA) is an end stage product of tryptophan metabolism with a variety of functions in the human body, both in the central nervous system (CNS) and in other organs. Although its activity in the human brain has been widely studied and effects on neural cells were emphasized, the effect of KYNA on oligodendroglial cells remains unknown. Present study aims at describing the activity of high concentration of KYNA in OLN-93 cells. The inhibition of OLN-93 oligodendrocytes viability by KYNA in a medium with reduced serum concentration has been demonstrated. Although decreased metabolic activity of KYNA treated OLN-93 cells was shown, the cells proliferation was not altered. KYNA treatment did not alter morphology as well as expression level of cell cycle and proliferation regulating proteins. Furthermore, glutamate receptor antagonists and agonists did not alter the inhibitory effect of KYNA on viability of OLN-93 oligodendrocytes. This study contributes to the elucidation of effects of KYNA on oligodendrocytes in vitro, yet further analyses are necessary to explain the mechanisms behind the damage and loss of myelin sheaths.