Αντινεοπλασματική δράση της Tinzaparin στον καρκίνο του παγκρέατος

Ο καρκίνος του Παγκρέατος αποτελεί την 4η πιο συχνή αιτία θανάτου από κακοήθεια στην Αμερική. Η Ηπαρίνη όπως και τα παράγωγά της, οι Ηπαρίνες Χαμηλού Μοριακού Βάρους, φαίνεται να δρουν κατά της νεοαγγειογένεσης και κατά της δημιουργίας μεταστάσεων. Η Tinzaparin ασκεί την νέο-αγγειογενετική της δράση καθώς φαίνεται να διεγείρει περισσότερο από κάθε άλλη Ηπαρίνη χαμηλού μοριακού βάρους την παραγωγή του Tissue Factor Pathway Inhibitor (TFPI) από τα επιθηλιακά κύτταρα, αναστέλλοντας τον Tissue Factor (TF) και κατά επέκταση τον VEGFR. Ο TFPI δρα αναστέλλοντας την ενεργοποίηση των Protease Activated Receptors 2 (PAR2), η ενεργοποίηση των οποίων διαδραματίζει σημαντικό ρόλο στο μεταστατικό δυναμικό που παρουσιάζει ο συγκεκριμένος τύπος καρκίνου. Η ενεργοποίηση του VEGFR-2 διεγείρει τον πολλαπλασιασμό και την επιβίωση των κυττάρων μέσω της ενεργοποίησης των σηματοδοτικών μονοπατιών PI3K/AKT/mTOR και RAF/ΜΕΚ/ERK. Προκειμένου να διερευνήσουμε εάν η Tinzaparin ασκεί αντινεοπλασματική δράση, χρησιμοποιήθηκαν τρείς ανθρώπινες αθανατοποιημένες καρκινικές κυτταρικές σειρές απομονωμένες από πάγκρεας. Οι άνω κυτταρικές σειρές επωάστηκαν με διαφορετικές συγκεντρώσεις του φαρμάκου Tinzaparin (Τ) (0.5 μΜ, 0.7 μΜ, 0.9 μΜ ), 1 μΜ Abraxane (Α) και 1 μΜ Gemcitabine (G), καθώς και συνδυασμό των φαρμάκων Α+Τ, G+T, A+G+T για 24 ώρες, και ελέχθηκαν μέσω της μεθόδου του ανοσοαποτύπωματος κατά Western (Western blotting) τα πρωτεϊνικά επίπεδα του VEGFR-2. Στις συγκεκριμένες συνθήκες μετρήθηκε η ανάπτυξη αποικιών με τη μέθοδο του Clonogenic Assay, καθώς καταγράφηκε και η μεταναστευτική ικανότητα των κυττάρων με τη μέθοδο του Scratch Assay. Τα αποτελέσματά μας κατέδειξαν πώς για τα κύτταρα PANC-1, η Tinzaparin 0.5 μΜ όταν συνδυαστεί με Abraxane ή/και Gemcitabine, φαίνεται να ασκεί αντινεοπλασματική δράση, καθώς η μετάλλαξη G12D του γονιδίου K-RAS που παρουσιάζει η συγκεκριμμένη κυτταρική σειρά φαίνεται να αποτελεί έναν αποτελεσματικό κυτταρικό στόχο, ενώ τα μονοπάτια Akt/mTOR/PI3K και BRAF/MEK/ERK, φαίνεται επίσης να ενεργοποιούνται.Pancreatic cancer is the fourth most common cause of malignancy in America. Heparins, as well as its derivatives, Low Molecular Weight Heparins, appear to act against neo-angiogenesis and metastasis. Tinzaparin exerts its neo-angiogenic effect as it appears to stimulate more than any other Low Molecular Weight Heparin the production of Tissue Factor Pathway Inhibitor (TFPI) from epithelial cells by inhibiting Tissue Factor (TF) and VEGFR. TFPI works by inhibiting the activation of Protease Activated Receptors 2 (PAR2), the activation of which plays an important role in the metastatic ability of this type of cancer. Activation of VEGFR-2 stimulates the proliferation and survival of cells by activating the PI3K / AKT / mTOR and RAF / MEK / ERK signaling pathways. In order to investigate whether Tinzaparin exerts antineoplasmatic activity, three human immortalized pancreatic cancer cell lines were used. The upper cell lines were incubated with different concentrations of Tinzaparin (T) (0.5 μM, 0.7 μM, 0.9 μM), 1 μM Abraxane (A) and 1 μM Gemcitabine (G), as well as a combination of A + T, G + T, A + G + T for 24 hours, and VEGFR-2 protein levels were tested by western blotting. Clonogenic Assay was performed in these specific conditions, as well as the migration capacity of the cells was recorded using the Scratch Assay method. Our results showed that for PANC-1 cells Tinzaparin 0.5 μM when combined with Abraxane and / or Gemcitabine appears to have antitumor activity, as the mutation of this particular cell line G12D of K-RAS gene appears to be an effective cellular target, whereas the pathways Akt / mTOR / PI3K and BRAF / MEK / ERK, also appear to be activated

The Interplay of Autophagy and Tumor Microenvironment in Colorectal Cancer—Ways of Enhancing Immunotherapy Action

Autophagy as a primary homeostatic and catabolic process is responsible for the degradation and recycling of proteins and cellular components. The mechanism of autophagy has a crucial role in several cellular functions and its dysregulation is associated with tumorigenesis, tumor–stroma interactions, and resistance to cancer therapy. A growing body of evidence suggests that autophagy is also a key regulator of the tumor microenvironment and cellular immune response in different types of cancer, including colorectal cancer (CRC). Furthermore, autophagy is responsible for initiating the immune response especially when it precedes cell death. However, the role of autophagy in CRC and the tumor microenvironment remains controversial. In this review, we identify the role of autophagy in tumor microenvironment regulation and the specific mechanism by which autophagy is implicated in immune responses during CRC tumorigenesis and the context of anticancer therapy

Combined 5 ' UTR RFLP analysis and VP1 sequencing for epidemic investigation of enteroviruses

Enteroviruses, the main cause of aseptic meningitis, consist of 100 serotypes, and many of them have been associated with large outbreaks. In the present study, a comparison of RFLP analysis of the 5' untranslated region (5'UTR) and sequencing of both the 5'UTR and VP1 regions was conducted for epidemiological linkage of 27 clinical enterovirus strains. The clinical enterovirus strains were clustered into five restriction profile groups. Even though the restriction profile clusters of clinical isolates were not related to those of the respective prototype strains, epidemiological relationships between the members of each cluster were observed. The restriction profile clusters in the 5'UTR corresponded to the phylogenetic clusters in the VP1 genomic region. The incongruence between the topology of Gior strain in 5'UTR and VP1 phylogenetic trees indicates a recombination event. The proposed RFLP assay in combination with VP1 sequencing can offer crucial epidemiological information about the circulating enteroviruses

A Pilot Study About the Dysfunction of Adipose Tissue in Male, Sleep Apneic Patients in Relation to Psychological Symptoms

Introduction: Obstructive sleep apnea (OSA) and its cardiometabolic alterations are closely associated with visceral obesity. Patients with OSA frequently present with symptoms of depression and anxiety. Although these subjective symptoms of OSA are the result of complex biological dysregulation, it remains unclear if they have a direct effect on the dysfunction of adipose tissue. Methods: In a pilot, prospective, randomized study, we evaluated 10 recently diagnosed male patients with severe OSA by full polysomnography (PSG) and 4 male non-apneic subjects matched for age and body mass index (BMI) with abdomen adipose tissue biopsies. Subjects with diabetes/prediabetes and cardiovascular and psychiatric diseases and who are current smokers were excluded. All patients underwent anthropometric measurements and completed the following questionnaires: Epworth Sleepiness Scale (ESS), Fatigue Severity Scale (FSS), and Hospital Anxiety and Depression Scale (HADS-A and HADS-D). Fasting venous blood samples were collected on the day after PSG, between 8:00 and 9:00 a.m., after an overnight fast. Fat biopsies were performed at the same time periods and adipose tissue samples of 300 mg were obtained from abdominal fat. Fat cell size, extent of fibrosis, vascularity, leukocyte common antigen inflammatory infiltration, and tissue macrophage accumulation were microscopically evaluated. Results: The mean age of the group was 47.4 +/- 13.8 years, with mean BMI of 35.8 +/- 4.8 kg/m(2) and mean apnea-hypopnea index of 79.4 +/- 46.1 events per hour of sleep (severe OSA). HADS-A and HADS-D scores were 5.8 +/- 2.3 (3.0-8.0) and 4.7 +/- 2.3 (2.0-8.0), respectively. HADS-A score correlated positively with macrophage accumulation in fat biopsy (r = 0.82, p = 0.047), whereas ESS, FSS, and HADS-D did not. Severity of fibrosis correlated largely with waist circumference (r = -0.66, p = 0.038) and neck circumference (r = -0.790, p = 0.006). Respiratory events correlated negatively with the extent of vascularization of adipose tissue (r = -0.614, p = 0.05). Conclusions: In the preliminary results of our pilot study, we assessed that the symptoms of anxiety mainly contribute to macrophage accumulation, whereas the increased number of respiratory events reduces the extent of vascularization in visceral fat in OSA. Based on this observation, further larger studies are required to verify if anxious OSA patients are more vulnerable to the metabolic manifestations of the syndrome