Developing Oncolytic Viruses for the Treatment of Cervical Cancer

Cervical cancer represents one of the most important malignancies among women worldwide. Current therapeutic approaches for cervical cancer are reported not only to be inadequate for metastatic cervical cancer, but are also considered as cytotoxic for several patients leading to serious side effects, which can have negative implications on the quality of life of women. Therefore, there is an urgent need for the development of innovative and effective treatment options. Oncolytic viruses can eventually become effective biological agents, since they preferentially infect and kill cancer cells, while leaving the normal tissue unaffected. Moreover, they are also able to leverage the host immune system response to limit tumor growth. This review aims to systematically describe and discuss the different types of oncolytic viruses generated for targeting cervical cancer cells, as well as the outcome of the combination of virotherapy with conventional therapies. Although many preclinical studies have evaluated the therapeutic efficacy of oncolytic viruses in cervical cancer, the number of clinical trials so far is limited, while their oncolytic properties are currently being tested in clinical trials for the treatment of other malignancies.

The Optimized γ-Globin Lentiviral Vector GGHI-mB-3D Leads to Nearly Therapeutic HbF Levels In Vitro in CD34+ Cells from Sickle Cell Disease Patients

We have previously demonstrated that both the original γ-globin lentiviral vector (LV) GGHI and the optimized GGHI-mB-3D LV, carrying the novel regulatory elements of the 3D HPFH-1 enhancer and the 3' β-globin UTR, can significantly increase HbF production in thalassemic CD34⁺ cells and ameliorate the disease phenotype in vitro. In the present study, we investigated whether the GGHI-mB-3D vector can also exhibit an equally therapeutic effect, following the transduction of sickle cell disease (SCD) CD34⁺ cells at MOI 100, leading to HbF increase coupled with HbS decrease, and thus, to phenotype improvement in vitro. We show that GGHI-mB-3D LV can lead to high and potentially therapeutic HbF levels, reaching a mean 2-fold increase to a mean value of VCN/cell of 1.0 and a mean transduction efficiency of 55%. Furthermore, this increase was accompanied by a significant 1.6-fold HbS decrease, a beneficial therapeutic feature for SCD. In summary, our data demonstrate the efficacy of the optimized γ-globin lentiviral vector to improve the SCD phenotype in vitro, and highlights its potential use in future clinical SCD trials.

Gene Therapy for Malignant and Benign Gynaecological Disorders: A Systematic Review of an Emerging Success Story

Simple Summary

This review discusses all the major advances in gene therapy of gynaecological disorders, highlighting the novel and potentially therapeutic perspectives associated with such an approach. It specifically focuses on the gene therapy strategies against major gynaecological malignant disorders, such as ovarian, cervical, and endometrial cancer, as well as benign disorders, such as uterine leiomyomas, endometriosis, placental, and embryo implantation disorders. The above therapeutic strategies, which employ both viral and non-viral systems for mutation compensation, suicide gene therapy, oncolytic virotherapy, antiangiogenesis and immunopotentiation approaches, have yielded promising results over the last decade, setting the grounds for successful clinical trials.

Abstract

Despite the major advances in screening and therapeutic approaches, gynaecological malignancies still present as a leading cause of death among women of reproductive age. Cervical cancer, although largely preventable through vaccination and regular screening, remains the fourth most common and most lethal cancer type in women, while the available treatment schemes still pose a fertility threat. Ovarian cancer is associated with high morbidity rates, primarily due to lack of symptoms and high relapse rates following treatment, whereas endometrial cancer, although usually curable by surgery, it still represents a therapeutic problem. On the other hand, benign abnormalities, such as fibroids, endometriosis, placental, and embryo implantation disorders, although not life-threatening, significantly affect women’s life and fertility and have high socio-economic impacts. In the last decade, targeted gene therapy approaches toward both malignant and benign gynaecological abnormalities have led to promising results, setting the ground for successful clinical trials. The above therapeutic strategies employ both viral and non-viral systems for mutation compensation, suicide gene therapy, oncolytic virotherapy, antiangiogenesis and immunopotentiation. This review discusses all the major advances in gene therapy of gynaecological disorders and highlights the novel and potentially therapeutic perspectives associated with such an approach.

p16/Ki-67 Dual Staining Is a Reliable Biomarker for Risk Stratification for Patients With Borderline/Mild Cytology in Cervical Cancer Screening

BACKGROUND/AIM

To evaluate p16/Ki-67 dual-staining performance for detection of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) in the management of women with minor cervical abnormalities.

PATIENTS AND METHODS

All 759 enrolled patients were tested for cytology, high-risk human papillomavirus (HR-HPV) and dual p16/Ki-67 staining.

RESULTS

Positivity rates for HR-HPV and dual staining increased as dysplasia was worsened from non-CIN (37.6% and 0%) to CIN1 (62.5% and 1.6%) and CIN2+ (98.7% and 97.3%), respectively. HPV18 and HPV16 exhibited the highest odds ratios (53.16 and 11.31) in the CIN2+ group. Both p16/Ki-67 dual staining and HR-HPV presented similar sensitivities (97.3% and 98.7%, respectively) for CIN2+ detection. Dual staining specificity, however, was 99.3%, significantly higher compared to HR-HPV testing (52.2%). The utility of dual staining was evaluated in different screening strategies and appeared to reduce the number of colposcopies required for the detection of CIN2+ cases.

CONCLUSION

p16/Ki-67 dual-staining cytology is a surrogate triage biomarker in cytology-based screening programs, with high performance for efficient risk stratification of women with mild cervical abnormalities.

Success Stories and Challenges Ahead in Hematopoietic Stem Cell Gene Therapy: Hemoglobinopathies as Disease Models

Gene therapy is a relatively novel field that amounts to around four decades of continuous growth with its good and bad moments. Currently, the field has entered the clinical arena with the ambition to fulfil its promises for a permanent fix of incurable genetic disorders. Hemoglobinopathies as target diseases and hematopoietic stem cells (HSCs) as target cells of genetic interventions had a major share in the research effort toward efficiently implementing gene therapy. Dissection of HSC biology and improvements in gene transfer and gene expression technologies evolved in an almost synchronous manner to a point where the two fields seem to be functionally intercalated. In this review, we focus specifically on the development of gene therapy for hemoglobin disorders and look at both gene addition and gene correction strategies that may dominate the field of HSC-directed gene therapy in the near future and transform the therapeutic landscape for genetic diseases.

Metabolic rewiring is associated with HPV-specific profiles in cervical cancer cell lines

Both HPV-positive and HPV-negative cervical cancers are associated with aberrant metabolism, although the oncogenic drivers remain elusive. Here we show the assessment of the metabolomic profiles of four distinct cervical cell lines, a normal and three cancer cell lines, one HPV-negative (C33A) and two HPV-positive (SiHa HPV16+, HeLa HPV18+), employing an ultra performance liquid chromatography and a high resolution mass spectrometry. Out of the total 462 metabolites, 248 to 326 exhibited statistically significant differences, while Random Forests analysis identified unique molecules for each cell line. The two HPV+ cell lines exhibited features of Warburg metabolism, consistent with the role of the HPV E6 protein. SiHa and HeLa cells displayed purine salvage pathway activity, while C33A cells revealed synthesis of cytidine, via a novel mechanism. These data document a highly dynamic HPV-specific rewiring of metabolic pathways occurring in cervical cancer. Therefore, this approach can eventually provide novel mechanistic insights into cervical carcinogenesis.

High resolution analysis of the intracellular proteome of cervical cancer cell lines unveils novel regulators of cervical carcinogenesis

Cervical cancer remains the fourth most common and most lethal type of cancer in women, despite the applied regular screening and prevention strategies, while the available treatment schemes still pose a threat to fertility. Substantial understanding of the underlying mechanisms and development of novel diagnostic, prognostic and therapeutic approaches are critical steps for improving cervical cancer management. Towards this goal, a comparative proteomic analysis was conducted between three cervical cancer cell lines (HeLa: HPV18+, SiHa: HPV16+, C33A: HPV‑) and normal cervical keratinocytes (HCK1T). The total cell extract of each cell line was analyzed by liquid chromatography coupled to tandem mass spectrometry (LC‑MS/MS). Differential expression analysis revealed 919, 826 and 1,370 deregulated proteins in the comparisons of HeLa, SiHa and C33A with HCK1T cell lines, respectively. Pathway enrichment analysis of the differentially expressed proteins highlighted common cancer characteristics such as high metabolic demands and increased cell turnover, confirming the validity of the proteomic results. Extensive literature mining of the consistently differentially expressed proteins that resulted from the three comparisons was performed leading to a shortlist of 21 proteins that are potentially involved in cervical malignancy. The criteria for this shortlisting were the association of the proteins with various types of cancer, while there is no study as yet associating their expression to cervical cancer. Moreover, the expression trend of two of the shortlisted proteins was validated using western blot analysis. The proteomic datasets generated in this study can be utilized to enrich the current knowledge on cervical cancer pathology and unveil key molecular mechanisms of carcinogenesis. In conclusion, the shortlist of consistently deregulated proteins between cervical cancer cell lines and normal cervical keratinocytes can be used for validation in clinical samples and in functional investigation experiments that could ultimately lead to the discovery of novel disease biomarkers and drug targets.

A Novel BaEVRless-Pseudotyped γ-Globin Lentiviral Vector Drives High and Stable Fetal Hemoglobin Expression and Improves Thalassemic Erythropoiesis In Vitro

It has previously been demonstrated that the self-inactivating γ-globin lentiviral vector GGHI can significantly increase fetal hemoglobin (HbF) in erythroid cells from thalassemia patients and thus improve the disease phenotype in vitro. In the present study, the GGHI vector was improved further by incorporating novel enhancer elements and also pseudotyping it with the baboon endogenous virus envelope glycoprotein BaEVRless, which efficiently and specifically targets human CD34⁺ cells. We evaluated the hypothesis that the newly constructed vector designated as GGHI-mB-3D would increase hCD34⁺ cell tropism and thus transduction efficiency at low multiplicity of infection, leading to increased transgene expression. High and stable HbF expression was demonstrated in thalassemic cells for the resulting GGHI-mB-3D/BaEVRless vector, exhibiting increased transduction efficiency compared to the original GGHI-mB-3D/VSVG vector, with a concomitant 91% mean HbF increase at a mean vector copy number per cell of 0.86 and a mean transduction efficiency of 56.4%. Transduced populations also exhibited a trend toward late erythroid, orthochromatic differentiation and reduced apoptosis, a further indication of successful gene therapy treatment. Monitoring expression of ATG5, a key link between autophagy and apoptosis, it was established that this correction correlates with a reduction of enhanced autophagy activation, a typical feature of thalassemic polychromatophilic normoblasts. This work provides novel mechanistic insights into gene therapy-mediated correction of erythropoiesis and demonstrates the beneficial role of BaEVRless envelope glycoprotein compared to VSVG pseudotyping and of the novel GGHI-mB-3D/BaEVRless lentiviral vector for enhanced thalassemia gene therapy.

Membrane proteomics of cervical cancer cell lines reveal insights on the process of cervical carcinogenesis

The available therapeutic approaches for cervical cancer can seriously affect the fertility potential of patient; thus, there is a pressing requirement for less toxic and targeted therapies. The membrane proteome is a potential source of therapeutic targets; however, despite the significance of membrane proteins in cancer, proteomic analysis has been a challenging task due to their unique biochemical properties. The aim of the present study was to develop an efficient membrane protein enrichment protocol, and to the best of our knowledge, to compare for the first time the expression pattern of membrane proteins of one normal cell line, HCK1T, and three cervical cancer cell lines, C33A, a human papilloma virus (HPV)-negative cell line, and two HPV-positive cell lines, SiHa (HPV16+) and HeLa (HPV18+). The study aimed to identify the proteins that are involved in cervical carcinogenesis and may constitute novel drug targets. Membrane protein isolation, liquid chromatography coupled with tandem mass spectrometry proteomics and bioinformatics analysis were performed in the membrane fraction of the informative cervical cell lines following a novel enrichment protocol. The percentages of membrane and transmembrane proteins in the enrichment protocol were higher compared with those of the corresponding data derived from total cell extract analysis. Differentially expressed proteins were detected by the comparison of the cervical cancer cell lines with the normal cell line. These proteins constitute molecular features of cancer pathology and participate in biological pathways relevant to malignancy, including 'HIPPO signaling', 'PI3K/Akt signaling', 'cell cycle: G2/M DNA damage checkpoint regulation' and 'EIF2 signaling'. These unique membrane protein identifications offer insights on a previously inaccessible region of the cervical cancer proteome, and may represent putative diagnostic and prognostic markers, and eventually therapeutic targets.

High Resolution Proteomic Analysis of the Cervical Cancer Cell Lines Secretome Documents Deregulation of Multiple Proteases

BACKGROUND

Oncogenic infection by HPV, eventually leads to cervical carcinogenesis, associated by deregulation of specific pathways and protein expression at the intracellular and secretome level. Thus, secretome analysis can elucidate the biological mechanisms contributing to cervical cancer. In the present study we systematically analyzed its constitution in four cervical cell lines employing a highly sensitive proteomic technology coupled with bioinformatics analysis.

MATERIALS AND METHODS

LC/MS-MS proteomics and bioinformatics analysis were performed in the secretome of four informative cervical cell lines SiHa (HPV16⁺), HeLa (HPV18⁺), C33A (HPV^-) and HCK1T (normal).

RESULTS

The proteomic pattern of each cancer cell line compared to HCK1T was identified and a detailed bioinformatics analysis disclosed inhibition of matrix metalloproteases in cancer cell lines. This prediction was further confirmed via zymography for MMP-2 and MMP-9, western blot analysis for ADAM10 and by MRM for TIMP1. The differential expression of important secreted proteins such as CATD, FUCA1 and SOD2 was also confirmed by western blot analysis. MRM-targeted proteomics analysis confirmed the differential expression of CATD, CATB, SOD2, QPCT and NEU1.

CONCLUSION

High resolution proteomics analysis of cervical cancer secretome revealed significantly deregulated biological processes and proteins implicated in cervical carcinogenesis.

Proteomic Analysis of Normal and Cancer Cervical Cell Lines Reveals Deregulation of Cytoskeleton-associated Proteins

BACKGROUND

Both HPV-positive and -negative cervical cancers are primarily associated with features of cell cycle and cytoskeletal disruption; however, the actual biological processes affected remain elusive. To this end, we systematically characterized the intracellular proteomic profiles of four distinct and informative cervical cell lines.

MATERIALS AND METHODS

Cell extracts from a normal cervical (HCK1T) and three cervical cancer cell lines, one HPV-negative (C33A), and two HPV-positive, SiHa (HPV16+) and HeLa (HPV18+), were analyzed by 2-dimensional electrophoresis and differentially expressed proteins were identified by MALDI-TOF mass spectrometry, while differential expression was confirmed by western blot analysis.

RESULTS

In total, 113 proteins were found differentially expressed between the normal and the cervical cancer lines. Bioinformatics analysis revealed the actin cytoskeleton signaling pathway to be significantly affected, while up-regulation of cofilin-1, an actin depolymerizing factor, was documented and further validated by western blotting. Furthermore, two-way comparisons among the four cell lines, revealed a set of 18 informative differentially expressed proteins.

CONCLUSION

These novel identified proteins provide the impetus for further functional studies to dissect the mechanisms operating in the two distinct pathways of cervical carcinogenesis.

Silencing of Profilin-1 suppresses cell adhesion and tumor growth via predicted alterations in integrin and Ca2+ signaling in T24M-based bladder cancer models

Bladder cancer (BC) is the second most common malignancy of the genitourinary system, characterized by the highest recurrence rate of all cancers. Treatment options are limited; thus a thorough understanding of the underlying molecular mechanisms is needed to guide the discovery of novel therapeutic targets. Profilins are actin binding proteins with attributed pleiotropic functions to cytoskeletal remodeling, cell adhesion, motility, even transcriptional regulation, not fully characterized yet. Earlier studies from our laboratory revealed that decreased tissue levels of Profilin-1 (PFN1) are correlated with BC progression to muscle invasive disease. Herein, we describe a comprehensive analysis of PFN1 silencing via shRNA, in vitro (by employing T24M cells) and in vivo [(with T24M xenografts in non-obese diabetic severe combined immunodeficient mice (NOD/SCID) mice]. A combination of phenotypic and molecular assays, including migration, proliferation, adhesion assays, flow cytometry and total mRNA sequencing, as well as immunohistochemistry for investigation of selected findings in human specimens were applied. A decrease in BC cell adhesion and tumor growth in vivo following PFN downregulation are observed, likely associated with the concomitant downregulation of Fibronectin receptor, Endothelin-1, and Actin polymerization. A decrease in the levels of multiple key members of the non-canonical Wnt/Ca²⁺ signaling pathway is also detected following PFN1 suppression, providing the groundwork for future studies, addressing the specific role of PFN1 in Ca²⁺ signaling, particularly in the muscle invasive disease.

Proteomics approaches in cervical cancer: focus on the discovery of biomarkers for diagnosis and drug treatment monitoring

INTRODUCTION

The HPV virus accounts for the majority of cervical cancer cases. Although a diagnostic tool (Pap Test) is widely available, cervical cancer incidence still remains high worldwide, and especially in developing countries, attributed to a large extent to suboptimal sensitivities of the Pap test and unavailability of the test in developing countries.

AREAS COVERED

Proteomics approaches have been used in order to understand the HPV virus correlation to cervical cancer pathology, as well as to discover putative biomarkers for early cervical cancer diagnosis and drug mode of action. Expert commentary: The present review summarizes the latest in vitro and in vivo proteomic studies for the discovery of putative cervical cancer biomarkers and the evaluation of available drugs and treatments.

The Q192R polymorphism of the paraoxonase-1 (PON1) gene is associated with susceptibility to gestational diabetes mellitus in the Greek population

A key factor protecting from oxidative stress in gestational diabetes mellitus (GDM) and in type 2 diabetes (T2D) is paraoxonase-1 (PON1). Inconclusive and limited data exist regarding the effect of a coding polymorphism (Q192R) of the PON1 gene in conferring susceptibility to both states. In the present study, we investigated the association between the PON1 gene and the risk for GDM in the Greek population and assessed for the first time its transcriptional efficiency. We studied 185 women with GDM and 104 non-diabetic controls for the PON1 polymorphism. For PON1 mRNA expression, peripheral leucocytes were harvested from 20 GDM and 20 control women, harboring different genotypes for the polymorphism, using real-time quantitative PCR. The RR genotype and the R allele of the PON1 Q192R polymorphism were significantly associated with an increased risk for GDM (p = 0.012 and p < 0.0001, respectively). Furthermore, there was no statistical correlation between the individual metabolic parameters tested and the three genotypes. Finally, the expression levels of PON1 mRNA in GDM patients did not exhibit any statistical difference compared with normal controls (p = 0.138). These data independently document that the Q192R polymorphism is closely associated with GDM susceptibility, while the PON1 gene expression is not impaired in GDM.

miR-26a Mediates Adipogenesis of Amniotic Fluid Mesenchymal Stem/Stromal Cells via PTEN, Cyclin E1, and CDK6

Recent findings indicate that microRNAs (miRNAs) are critical for the regulatory network of adipogenesis in human mesenchymal stem/stromal cells (MSCs). Fetal MSCs derived from amniotic fluid (AF-MSCs) represent a population of multipotent stem cells characterized by a wide range of differentiation properties that can be applied in cell-based therapies. In this study, miRNA microarray analysis was performed to assess miRNA expression in terminal differentiated AF-MSCs into adipocyte-like cells (AL cells). MiR-26a was identified in high expression levels in AL cells indicating a critical role in the process of adipogenesis. Overexpression of miR-26a in AF-MSCs led to significant induction of their adipogenic differentiation properties that were altered after miR-26a inhibition. We have demonstrated that miR-26a regulates adipogenesis through direct inhibition of PTEN, which in turn promotes activation of Akt pathway. Also, miR-26a modulates cell cycle during adipogenesis by interacting with Cyclin E1 and CDK6. These results point to the regulatory role of miR-26a and its target genes PTEN, Cyclin E1, and CDK6 in adipogenic differentiation of AF-MSCs, providing a basis for understanding the mechanisms of fat cell development and obesity.

Polymorphism Analysis of VSX1 and SOD1 Genes in Greek Patients with Keratoconus

BACKGROUND

A number of mutations in the VSX1 and SOD1 genes have been reported to be associated with keratoconus (KC), however the results from different studies are controversial. In this study, we conducted the genotyping of common polymorphisms [VSX1: D144E, H244R, R166W, G160D; SOD1: intronic 7-base deletion (c.169 + 50 delTAAACAG)], in a case-control sample panel of the Greek population.

MATERIALS AND METHODS

A case-control panel, with 33 KC patients and 78 healthy controls, were surveyed. DNA from each individual was tested for the VSX1: D144E, H244R, R166W, G160D and SOD1: intronic 7-base deletion (c.169 + 50 delTAAACAG) polymorphisms by direct sequencing.

RESULTS

We observed no polymorphisms of the VSX1 gene in the case-control panel. Concerning the SOD1 intronic 7-base deletion (c.169 + 50 delTAAACAG), our findings suggest that heterozygous carriers are over-represented among KC cases compared to healthy controls (p = 0.002).

CONCLUSIONS

We cannot confirm the previously reported association of the polymorphism in the VSX1 gene with KC. Our results suggest a possible causative role of SOD1 in the pathogenesis of KC. Further studies are required to identify other important genetic factors involved in the pathogenesis and progression of KC.

Development and Validation of Urine-based Peptide Biomarker Panels for Detecting Bladder Cancer in a Multi-center Study

PURPOSE

Urothelial bladder cancer presents high recurrence rates, mandating continuous monitoring via invasive cystoscopy. The development of noninvasive tests for disease diagnosis and surveillance remains an unmet clinical need. In this study, validation of two urine-based biomarker panels for detecting primary and recurrent urothelial bladder cancer was conducted.

EXPERIMENTAL DESIGN

Two studies (total n = 1,357) were performed for detecting primary (n = 721) and relapsed urothelial bladder cancer (n = 636). Cystoscopy was applied for detecting urothelial bladder cancer, while patients negative for recurrence had follow-up for at least one year to exclude presence of an undetected tumor at the time of sampling. Capillary electrophoresis coupled to mass spectrometry (CE-MS) was employed for the identification of urinary peptide biomarkers. The candidate urine-based peptide biomarker panels were derived from nested cross-sectional studies in primary (n = 451) and recurrent (n = 425) urothelial bladder cancer.

RESULTS

Two biomarker panels were developed on the basis of 116 and 106 peptide biomarkers using support vector machine algorithms. Validation of the urine-based biomarker panels in independent validation sets, resulted in AUC values of 0.87 and 0.75 for detecting primary (n = 270) and recurrent urothelial bladder cancer (n = 211), respectively. At the optimal threshold, the classifier for detecting primary urothelial bladder cancer exhibited 91% sensitivity and 68% specificity, while the classifier for recurrence demonstrated 87% sensitivity and 51% specificity. Particularly for patients undergoing surveillance, improved performance was achieved when combining the urine-based panel with cytology (AUC = 0.87).

CONCLUSIONS

The developed urine-based peptide biomarker panel for detecting primary urothelial bladder cancer exhibits good performance. Combination of the urine-based panel and cytology resulted in improved performance for detecting disease recurrence. Clin Cancer Res; 22(16); 4077-86. ©2016 AACR.

Profiling of Discrete Gynecological Cancers Reveals Novel Transcriptional Modules and Common Features Shared by Other Cancer Types and Embryonic Stem Cells

Studies on individual types of gynecological cancers (GCs), utilizing novel expression technologies, have revealed specific pathogenetic patterns and gene markers for cervical (CC), endometrial (EC) and vulvar cancer (VC). Although the clinical phenotypes of the three types of gynecological cancers are discrete, the fact they originate from a common embryological origin, has led to the hypothesis that they might share common features reflecting regression to early embryogenesis. To address this question, we performed a comprehensive comparative analysis of their profiles. Our data identified both common features (pathways and networks) and novel distinct modules controlling the same deregulated biological processes in all three types. Specifically, four novel transcriptional modules were discovered regulating cell cycle and apoptosis. Integration and comparison of our data with other databases, led to the identification of common features among cancer types, embryonic stem (ES) cells and the newly discovered cell population of squamocolumnar (SC) junction of the cervix, considered to host the early cancer events. Conclusively, these data lead us to propose the presence of common features among gynecological cancers, other types of cancers, ES cells and the pre-malignant SC junction cells, where the novel E2F/NFY and MAX/CEBP modules play an important role for the pathogenesis of gynecological carcinomas.

Platelet-rich plasma (PRP) promotes fetal mesenchymal stem/stromal cell migration and wound healing process

Numerous studies have shown the presence of high levels of growth factors during the process of healing. Growth factors act by binding to the cell surface receptors and contribute to the subsequent activation of signal transduction mechanisms. Wound healing requires a complex of biological and molecular events that includes attraction and proliferation of different type of cells to the wound site, differentiation and angiogenesis. More specifically, migration of various cell types, such as endothelial cells and their precursors, mesenchymal stem/stromal cells (MSCs) or skin fibroblasts (DFs) plays an important role in the healing process. In recent years, the application of platelet rich plasma (PRP) to surgical wounds and skin ulcerations is becoming more frequent, as it is believed to accelerate the healing process. The local enrichment of growth factors at the wound after PRP application causes a stimulation of tissue regeneration. Herein, we studied: (i) the effect of autologous PRP in skin ulcers of patients of different aetiology, (ii) the proteomic profile of PRP, (iii) the migration potential of amniotic fluid MSCs and DFs in the presence of PRP extract in vitro, (iv) the use of the PRP extract as a substitute for serum in cultivating AF-MSCs. Considering its easy access, PRP may provide a valuable tool in multiple therapeutic approaches.

Quantum dots-bevacizumab complexes for in vivo imaging of tumors

BACKGROUND/AIM

The basic role of vascular endothelial growth factor (VEGF) in cancer is underscored by the approval of bevacizumab for first-line treatment of cancer patients. Recent anticancer therapeutics based on active tumor targeting by conjugating tumor-specific antibodies has become of great interest in oncology. Current progress in nanomedicine has exploited the possibility of designing tumor-targeted nanocarriers able to deliver specific molecule payloads in a selective manner to improve the efficacy and safety of cancer imaging and therapy. We herein aimed to determine the targeting ability of bevacizumab-conjugated quantum dots (QDs) in vitro and in vivo.

MATERIALS AND METHODS

We used QDs labeled with bevacizumab, in various in vitro experiments using cell lines derived from colorectal cancer (CRC) and breast cancer (BC). For a competition study of QD-bevacizumab complex and bevacizumab, the cells were pre-treated with bevacizumab (100 nmol/L) for 24 h before exposure to the QD-bevacizumab complex. The breast cancer cells (MDA-MB-231) were injected to 9 nude mice to make the xenograft tumor model. The QD-bevacizumab complex was injected into the tumor model and fluorescence measurements were performed at 1, 12, and 24 h post-injection.

RESULTS

Immunocytochemical data confirmed strong and specific binding of the QD-bevacizumab complex to the cell lines. The cells pre-treated with an excess of bevacizumab showed absence of QD binding. The in vivo fluorescence image disclosed that there was an increased signal of tumor after the injection of QDs. Ex vivo analysis showed 3.1 ± 0.8%, 28.6 ± 5.4% and 30.8 ± 4.2% injected dose/g accumulated in the tumors at 1, 12 and 24 h respectively. Tumor uptake was significantly decreased in the animals pretreated with excess of bevacizumab (p=0.001).

CONCLUSION

In conclusion, we could successfully detect the VEGF-expressing tumors using QDs-bevacizumab nanoprobes in vitro and in vivo, opening new perspectives for VEGF-targeted non-invasive imaging in clinical practice.

Towards more successful gene therapy clinical trials for β-thalassemia

β-thalassemias constitute hereditary blood disorders characterized by reduced or absence of β-globin synthesis resulting in mild to severe anemia, depending on the genotype. More than 200 mutations in the β-globin gene are responsible for their specific features leading to a very heterogeneous phenotype. Current therapies for β-thalassemia include blood transfusions, usually along with iron chelation and in selected cases with bone marrow transplantation (BMT) of HLA-matched hematopoietic stem cells (HSCs). However, these approaches are limited by factors, such as iron overload and donor availability, respectively. Since 2000, when globin lentiviral vectors (LVs) were first successfully tested for transfer efficiency of the therapeutic transgene, which led to disease amelioration in murine models, attention was drawn towards the improvement of such vectors for β-thalassemia gene therapy. Constantly improving vector design and efficient HSC manipulation led recently to the first successful clinical trial in France, which further proved that this genetic approach can be curative. Furthermore, improved new efficient vectors and methods to safely monitor integration sites and therapeutic transgene position effects, promise a new era for β-thalassemia gene therapy, with more and safer clinical trials yet to come.

Sox2 suppression by miR-21 governs human mesenchymal stem cell properties

MicroRNAs (miRNAs) have recently been shown to act as regulatory signals for maintaining stemness and for determining the fate of adult and fetal stem cells, such as human mesenchymal stem cells (hMSCs). hMSCs constitute a population of multipotent stem cells that can be expanded easily in culture and are able to differentiate into many lineages. We have isolated two subpopulations of fetal mesenchymal stem cells (MSCs) from amniotic fluid (AF) known as spindle-shaped (SS) and round-shaped (RS) cells and characterized them on the basis of their phenotypes, pluripotency, proliferation rates, and differentiation potentials. In this study, we analyzed the miRNA profile of MSCs derived from AF, bone marrow (BM), and umbilical cord blood (UCB). We initially identified 67 different miRNAs that were expressed in all three types of MSCs but at different levels, depending on the source. A more detailed analysis revealed that miR-21 was expressed at higher levels in RS-AF-MSCs and BM-MSCs compared with SS-AF-MSCs. We further demonstrated for the first time a direct interaction between miR-21 and the pluripotency marker Sox2. The induction of miR-21 strongly inhibited Sox2 expression in SS-AF-MSCs, resulting in reduced clonogenic and proliferative potential and cell cycle arrest. Strikingly, the opposite effect was observed upon miR-21 inhibition in RS-AF-MSCs and BM-MSCs, which led to an enhanced proliferation rate. Finally, miR-21 induction accelerated osteogenesis and impaired adipogenesis and chondrogenesis in SS-AF-MSCs. Therefore, these findings suggest that miR-21 might specifically function by regulating Sox2 expression in human MSCs and might also act as a key molecule determining MSC proliferation and differentiation.

Serum protein profile of Crohn's disease treated with infliximab

The infliximab (IFX) has dramatically improved the treatment of Crohn's disease (CD). However, the need for predictive factors, indicative of patients' response to IFX, has yet to be met. In the current study, proteomics technologies were employed in order to monitor for differences in protein expression in a cohort of patients following IFX administration, aiming at identifying a panel of candidate protein biomarkers of CD, symptomatic of response to treatment. We enrolled 18 patients, who either had achieved clinical and serological remission (Rm, n=6), or response (Rs, n=6) and/or were PNRs (n=6), to IFX. Serum samples were subjected to two-dimensional Gel Electrophoresis. Following evaluation of densitometrical data, protein spots exhibiting differential expression among the groups, were further characterized by MALDI-TOF-MS. Identified proteins where evaluated by immunoblot analysis while functional network association was carried out to asses significance. Proteins apolipoprotein A-I (APOA1), apolipoprotein E (APOE), complement C4-B (CO4B), plasminogen (PLMN), serotransferrin (TRFE), beta-2-glycoprotein 1 (APOH), and clusterin (CLUS) were found to be up-regulated in the PNR and Rs groups whereas their levels displayed no changes in the Rm group when compared to baseline samples. Additionally, leucine-rich alpha-2-glycoprotein (A2GL), vitamin D-binding protein (VTDB), alpha-1B-glycoprotein (A1BG) and complement C1r subcomponent (C1R) were significantly increased in the serum of the Rm group. Through the incorporation of proteomics technologies, novel serum marker-molecules demonstrating high sensitivity and specificity are introduced, hence offering an innovative approach regarding the evaluation of CD patients' response to IFX therapy.

AF-MSCs fate can be regulated by culture conditions

Human mesenchymal stem cells (hMSCs) represent a population of multipotent adherent cells able to differentiate into many lineages. In our previous studies, we isolated and expanded fetal MSCs from second-trimester amniotic fluid (AF) and characterized them based on their phenotype, pluripotency and proteomic profile. In the present study, we investigated the plasticity of these cells based on their differentiation, dedifferentiation and transdifferentiation potential in vitro. To this end, adipocyte-like cells (AL cells) derived from AF-MSCs can regain, under certain culture conditions, a more primitive phenotype through the process of dedifferentiation. Dedifferentiated AL cells derived from AF-MSCs (DAF-MSCs), gradually lost the expression of adipogenic markers and obtained similar morphology and differentiation potential to AF-MSCs, together with regaining the pluripotency marker expression. Moreover, a comparative proteomic analysis of AF-MSCs, AL cells and DAF-MSCs revealed 31 differentially expressed proteins among the three cell populations. Proteins, such as vimentin, galectin-1 and prohibitin that have a significant role in stem cell regulatory mechanisms, were expressed in higher levels in AF-MSCs and DAF-MSCs compared with AL cells. We next investigated whether AL cells could transdifferentiate into hepatocyte-like cells (HL cells) directly or through a dedifferentiation step. AL cells were cultured in hepatogenic medium and 4 days later they obtained a phenotype similar to AF-MSCs, and were termed as transdifferentiated AF-MSCs (TRAF-MSCs). This finding, together with the increase in pluripotency marker expression, indicated the adaption of a more primitive phenotype before transdifferentiation. Additionally, we observed that AF-, DAF- and TRAF-MSCs displayed similar clonogenic potential, secretome and proteome profile. Considering the easy access to this fetal cell source, the plasticity of AF-MSCs and their potential to dedifferentiate and transdifferentiate, AF may provide a valuable tool for cell therapy and tissue engineering applications.

Circadian clock gene expression is impaired in gestational diabetes mellitus

Dysfunction of the circadian clock genes is involved in the development of obesity and type 2 diabetes (T2D). Since gestational diabetes mellitus (GDM) and T2D share common genetic and phenotypic features, in the present study, we investigated the status of the circadian clock in a cohort of 40 Greek pregnant women with GDM, four with T2D and 20 normal controls. Peripheral blood mRNA transcript levels of 10 clock genes (CLOCK1, BMAL1, PER1, PER2, PER3, PPARΑ, PPARD, PPARG, CRY1 and CRY2) were determined by real-time quantitative PCR. GDM patients expressed significantly lower transcript levels of BMAL1, PER3, PPARD and CRY2 compared to control women (p < 0.05). No significant difference was documented between GDM women maintained either under insulin treatment or diet. A positive correlation was found between the expression of BMAL1 versus CRY2 (r = 0.45, p = 0.003) and BMAL1 versus PPARD (r = 0.43, p = 0.004). Further investigation on the functional relevance of these clock genes, disclosed that expression of PER3 correlated negatively with HbA1C levels (r = -0.36, p = 0.022). These data document for the first time that the expression of BMAL1, PER3, PPARD and CRY2 genes is altered in GDM compared to normal pregnant women and support the notion that deranged expression of clock genes may play a pathogenic role in GDM.

The major circadian pacemaker ARNT-like protein-1 (BMAL1) is associated with susceptibility to gestational diabetes mellitus

AIMS

Recently a relationship between circadian clock function and the risk for type 2 diabetes (T2D) has been shown. BMAL1 is a key component of the mammalian molecular clock. Two SNPs in the BMAL1 gene have been identified to confer T2D susceptibility. In the present study we investigated for the first time the association between the BMAL1 gene and the risk for GDM, in a Greek population.

METHODS

We studied 185 women with GDM and 161 non-diabetic controls for BMAL1 polymorphisms. For BMAL1 mRNA expression, peripheral leukocytes were harvested from 20 GDM and 20 control women, harboring different genotypes for the tested polymorphisms, using real-time quantitative PCR.

RESULTS

The minor allele (A) of the BMAL1 rs7950226 (G>A) polymorphism was found to be significantly associated with an increased risk of GDM (P=0.025). Analysis of the second BMAL1 rs11022775 (T>C) polymorphism, showed that the C-allele frequency was strongly increased in women with GDM (P=4.455e-06). The CC genotype was also significantly overrepresented in GDM vs. controls (P=0.00001). Additionally, the rs7950226G/rs11022775C and rs7950226A/rs11022775C haplotypes were also found to be associated with increased susceptibility to GDM. Furthermore, the expression levels of BMAL1 mRNA were significantly lower in GDM patients than in controls.

CONCLUSION

These data suggest that the impairment of the BMAL1 clock gene expression is closely associated with GDM susceptibility.

Spindle shaped human mesenchymal stem/stromal cells from amniotic fluid promote neovascularization

Human amniotic fluid obtained at amniocentesis, when cultured, generates at least two morphologically distinct mesenchymal stem/stromal cell (MSC) subsets. Of these, the spindle shaped amniotic fluid MSCs (SS-AF-MSCs) contain multipotent cells with enhanced adipogenic, osteogenic and chondrogenic capacity. Here, we demonstrate, for the first time, the capacity of these SS-AF-MSCs to support neovascularization by umbilical cord blood (UCB) endothelial colony forming cell (ECFC) derived cells in both in vitro and in vivo models. Interestingly, although the kinetics of vascular tubule formation in vitro were similar when the supporting SS-AF-MSCs were compared with the best vasculogenic supportive batches of bone marrow MSCs (BMSCs) or human dermal fibroblasts (hDFs), SS-AF-MSCs supported vascular tubule formation in vivo more effectively than BMSCs. In NOD/SCID mice, the human vessels inosculated with murine vessels demonstrating their functionality. Proteome profiler array analyses revealed both common and distinct secretion profiles of angiogenic factors by the SS-AF-MSCs as opposed to the hDFs and BMSCs. Thus, SS-AF-MSCs, which are considered to be less mature developmentally than adult BMSCs, and intermediate between adult and embryonic stem cells in their potentiality, have the additional and very interesting potential of supporting increased neovascularisation, further enhancing their promise as vehicles for tissue repair and regeneration.

Transcription factor ATF-3 regulates allele variation phenotypes of the human SLC11A1 gene

Genetic polymorphisms in the human solute carrier family 11 member 1 (SLC11A1) gene predispose to susceptibility to infectious/inflammatory diseases and cancer. Human susceptibility to these diseases exhibits allelic association with a polymorphic regulatory Z-DNA-forming microsatellite of a (GT/AC)n repeat. The carriage of different alleles may influence chromatin remodeling and accessibility by transcription factors. Of particular importance is the binding site for the Activating Protein 1 (AP-1) elements, (ATF-3 and c-Jun), adjacent to the 5' sequence of the Z-DNA-forming polymorphism. The aim of the study was to characterize the transcriptional mechanisms controlling different alleles of SLC11A1 expression by ATF-3 and c-Jun. Allele 2, [T(GT)5AC(GT)5AC(GT)10GGCAGA(G)6], and Allele 3, [T(GT)5AC(GT)5AC(GT)9GGCAGA(G)6], were subcloned into the PGL2Basic vector. Transient transfections of THP-1 cells with the constructs, in the presence or absence of pATF-3 were preformed. Luciferase expression was determined. To document the recruitment of ATF-3 and c-Jun, to the polymorphic promoter alleles in vivo, we performed ChIP assays with transient transfected THP-1 cells treated with or without lipopolyssacharides. Our data documented that ATF-3 suppresses the transcriptional activation of Allele-3, and this suppression is enhanced in the presence of lipopolyssacharides. Our findings suggest that ATF-3 and c-Jun may influence heritable variation in SLC11A1-dependent innate resistance to infection and inflammation both within and between populations.

Human amniotic fluid stem cells as an attractive tool for clinical applications

Recent studies support cell based therapies for several diseases. Human fetal stem cells have received much attention for developing new therapeutic strategies. Recently, our group and others have successfully isolated and expanded karyotypically normal stem cells from an alternative fetal source, the human second trimester amniotic fluid (AF) and performed a systematic phenotypic and molecular analysis. The main characteristics of amniotic fluid stem cells (hAFSCs) are their fetal origin, the high number of isolated cells, their wide differentiation properties and their rapid expansion in vitro. These characteristics render hAFSCs as a very attractive tool for clinical applications based on cell therapy. The use of hAFSC transplantation has been studied in a variety of disease animal models related to bone regeneration, myocardial infarction, acute kidney injury, acute hepatic failure, skin injury, ischemic hind limb or cancer. The major aim of this review is to summarize the advent of hAFSCs capabilities into novel therapeutic modalities and discuss their potential use in future pre-clinical and clinical studies.

Development of a quantum-dot-labelled magnetic immunoassay method for circulating colorectal cancer cell detection

AIM: To detect of colorectal cancer (CRC) circulating tumour cells (CTCs) surface antigens, we present an assay incorporating cadmium selenide quantum dots (QDs) in these paper.

METHODS: The principle of the assay is the immunomagnetic separation of CTCs from body fluids in conjunction with QDs, using specific antibody biomarkers: epithelial cell adhesion molecule antibody, and monoclonal cytokeratin 19 antibody. The detection signal was acquired from the fluorescence signal of QDs. For the evaluation of the performance, the method under study was used to isolate the human colon adenocarcinoma cell line (DLD-1) and CTCs from CRC patients’ peripheral blood.

RESULTS: The minimum detection limit of the assay was defined to 10 DLD-1 CRC cells/mL as fluorescence was measured with a spectrofluorometer. Fluorescence-activated cell sorting analysis and Real Time RT-PCR, they both have also been used to evaluate the performance of the described method. In conclusion, we developed a simple, sensitive, efficient and of lower cost (than the existing ones) method for the detection of CRC CTCs in human samples. We have accomplished these results by using magnetic bead isolation and subsequent QD fluorescence detection.

CONCLUSION: The method described here can be easily adjusted for any other protein target of either the CTC or the host.

Therapeutic potential of a distinct population of human amniotic fluid mesenchymal stem cells and their secreted molecules in mice with acute hepatic failure

BACKGROUND

There is increasing interest in the therapeutic potential of human mesenchymal stem cells (hMSCs), especially in diseases such as acute hepatic failure (AHF) that are predominantly caused by a variety of drugs and viruses. In previous studies, a distinct population termed human spindle-shaped MSCs were isolated and expanded from second trimester amniotic fluid (AF-MSCs) and characterised based on their phenotype, pluripotency and differentiation potential.

METHODS

AF-MSCs, hepatic progenitor-like (HPL) cells and hepatocyte-like (HL) cells derived from AF-MSCs were transplanted into CCl₄-injured NOD/SCID mice with the AHF phenotype in order to evaluate their therapeutic potential. Conditioned medium (CM) derived from AF-MSCs or HPL cells was then delivered intrahepatically in order to determine whether the engraftment of the cells or their secreted molecules are the most important agents for liver repair.

RESULTS

Both HPL cells and AF-MSCs were incorporated into CCl(4)-injured livers; HPL cell transplantation had a greater therapeutic effect. In contrast, HL cells failed to engraft and contribute to recovery. In addition, HPL-CM was found to be more efficient than CM derived from AF-MSCs in treatment of the liver. Proteome profile analysis of HPL-CM indicated the presence of anti-inflammatory factors such as interleukins IL-10, IL-1ra, IL-13 and IL-27 which may induce liver recovery. Blocking studies of IL-10 secretion from HPL cells confirmed the therapeutic significance of this cytokine in the AHF mouse model.

CONCLUSIONS

Human spindle-shaped AF-MSCs or HPL cells might be valuable tools to induce liver repair and support liver function by cell transplantation. More importantly, the factors they release may also play an important role in cell treatment in diseases of the liver.

In vitro and in vivo properties of distinct populations of amniotic fluid mesenchymal progenitor cells

Human mesenchymal progenitor cells (MPCs) are considered to be of great promise for use in tissue repair and regenerative medicine. MPCs represent multipotent adherent cells, able to give rise to multiple mesenchymal lineages such as osteoblasts, adipocytes or chondrocytes. Recently, we identified and characterized human second trimester amniotic fluid (AF) as a novel source of MPCs. Herein, we found that early colonies of AF-MPCs consisted of two morphologically distinct adherent cell types, termed as spindle-shaped (SS) and round-shaped (RS). A detailed analysis of these two populations showed that SS-AF-MPCs expressed CD90 antigen in a higher level and exhibited a greater proliferation and differentiation potential. To characterize better the molecular identity of these two populations, we have generated a comparative proteomic map of SS-AF-MPCs and RS-AF-MPCs, identifying 25 differentially expressed proteins and 10 proteins uniquely expressed in RS-AF-MPCs. Furthermore, SS-AF-MPCs exhibited significantly higher migration ability on extracellular matrices, such as fibronectin and laminin in vitro, compared to RS-AF-MPCs and thus we further evaluated SS-AF-MPCs for potential use as therapeutic tools in vivo. Therefore, we tested whether GFP-lentiviral transduced SS-AF-MPCs retained their stem cell identity, proliferation and differentiation potential. GFP-SS-AF-MPCs were then successfully delivered into immunosuppressed mice, distributed in different tissues and survived longterm in vivo. In summary, these results demonstrated that AF-MPCs consisted of at least two different MPC populations. In addition, SS-AF-MPCs, isolated based on their colony morphology and CD90 expression, represented the only MPC population that can be expanded easily in culture and used as an efficient tool for future in vivo therapeutic applications.

Thiopurine methyltransferase genotype and thiopurine S-methyltransferase activity in Greek children with inflammatory bowel disease

BACKGROUND

Azathioprine (AZA) and 6-mercaptopurine (6MP) are used in the treatment of pediatric inflammatory bowel disease (IBD). Genetic variations in thiopurine S-methyltranfarase (TPMT) gene have been correlated with enzyme activity and with the occurrence of adverse events to AZA and 6MP. The aim of the present study was to examine the sensitivity and specificity of TPMT genotyping for TPMT enzymatic activity, reducing harm from thiopurine by pretesting, and the association of thiopurine toxicity with TPMT status in children with IBD.

METHODS

TPMT red blood cell (RBC) activity was measured by using a radiochemical method and genotype was determined for the TPMT alleles *2, *3A, *3B and *3C in 108 thiopurinetreated pediatric IBD patients with a mean age of 11.3 years (range 3-16).

RESULTS

Significant TPMT activity differences between wild-type and heterozygous and homozygous mutated subjects were observed. We divided TPMT activity into three categories according to frequency distribution: low (16.67%), intermediate (25.92%) and high (57.41%). The whole population included a total of 77.78% of homozygous wild-type subjects, 15.74% heterozygous variants, 1.85% homozygous variants and five (4.63%) compound heterozygous variant TPMT*3B/*3C. The overall concordance rate between TPMT genotypes and phenotypes was 88.2%. Seven carriers of at least one variant allele and low or intermediate TPMT activity developed adverse effects.

CONCLUSIONS

Our findings suggest that carriers of at least one variant allele and both intermediate and absent TPMT activity have an increased risk of developing thiopurine-induced myelotoxicity compared with individuals with normal genotype and TPMT activity.

The new self-inactivating lentiviral vector for thalassemia gene therapy combining two HPFH activating elements corrects human thalassemic hematopoietic stem cells

To address how low titer, variable expression, and gene silencing affect gene therapy vectors for hemoglobinopathies, in a previous study we successfully used the HPFH (hereditary persistence of fetal hemoglobin)-2 enhancer in a series of oncoretroviral vectors. On the basis of these data, we generated a novel insulated self-inactivating (SIN) lentiviral vector, termed GGHI, carrying the (A)γ-globin gene with the -117 HPFH point mutation and the HPFH-2 enhancer and exhibiting a pancellular pattern of (A)γ-globin gene expression in MEL-585 clones. To assess the eventual clinical feasibility of this vector, GGHI was tested on CD34(+) hematopoietic stem cells from nonmobilized peripheral blood or bone marrow from 20 patients with β-thalassemia. Our results show that GGHI increased the production of γ-globin by 32.9% as measured by high-performance liquid chromatography (p=0.001), with a mean vector copy number per cell of 1.1 and a mean transduction efficiency of 40.3%. Transduced populations also exhibited a lower rate of apoptosis and resulted in improvement of erythropoiesis with a higher percentage of orthochromatic erythroblasts. This is the first report of a locus control region (LCR)-free SIN insulated lentiviral vector that can be used to efficiently produce the anticipated therapeutic levels of γ-globin protein in the erythroid progeny of primary human thalassemic hematopoietic stem cells in vitro.

The Ongoing Challenge of Hematopoietic Stem Cell-Based Gene Therapy for β-Thalassemia

β-thalassemia is characterized by reduced or absence of β-globin production, resulting in anemia. Current therapies include blood transfusion combined with iron chelation. BM transplantation, although curative, is restricted by the matched donor limitation. Gene therapy, on the other hand, is promising, and its success lies primarily on designing efficient globin vectors that can effectively and stably transduce HSCs. The major breakthrough in β-thalassemia gene therapy occurred a decade ago with the development of globin LVs. Since then, researchers focused on designing efficient and safe vectors, which can successfully deliver the therapeutic transgene, demonstrating no insertional mutagenesis. Furthermore, as human HSCs have intrinsic barriers to HIV-1 infection, attention is drawn towards their ex vivo manipulation, aiming to achieve higher yield of genetically modified HSCs. This paper presents the current status of gene therapy for β-thalassemia, its success and limitations, and the novel promising strategies available involving the therapeutic role of HSCs.

Serotonin transporter and G protein beta 3 subunit gene polymorphisms in Greeks with irritable bowel syndrome

BACKGROUND

Polymorphisms in the serotonin transporter (SERT) and G protein β3 subunit (GNB3) genes might contribute to the pathophysiology of irritable bowel syndrome (IBS). Association studies of SERT and GNB3 polymorphisms and IBS have shown diverse results among different populations, which might be due to subject composition differences.

AIMS

The aim of the study was to assess the potential association between SERT and GNB3 polymorphisms and IBS in Greeks.

METHODS

A total of 124 patients with IBS diagnosed according to the Rome III criteria and 238 healthy individuals were included in the study. SERT and GNB3 gene polymorphisms were genotyped using polymerase chain reaction-based methods.

RESULTS

It was shown that the frequencies of the SS genotype and S allele of the serotonin transporter polymorphism were significantly associated with IBS (P = 0.0314 and P = 0.019, respectively). TT genotype and T allele frequencies of G protein β3 subunit showed also significant difference between the IBS patients and healthy controls IBS (P = 0.0163 and P = 0.0001, respectively). None of the clinical symptoms analyzed was significantly associated with the polymorphisms tested.

CONCLUSIONS

The results suggest that SERT and GNB3 gene polymorphisms might be associated with irritable bowel syndrome predisposition in Greeks.

Human amniotic fluid-derived mesenchymal stem cells as therapeutic vehicles: a novel approach for the treatment of bladder cancer

Recent studies support cell-based therapies for cancer treatment. An advantageous cell type for such therapeutic schemes are the mesenchymal stem cells (MSCs) that can be easily propagated in culture, genetically modified to express therapeutic proteins, and exhibit an innate tropism to solid tumors in vivo. Recently, we successfully isolated and expanded MSCs from second-trimester amniotic fluid (AF-MSCs). The main characteristic of AF-MSCs is their efficient and rapid expansion in vitro. Herein, we investigated the AF-MSCs tropism and capability to transport interferon beta (IFNβ) to the region of neoplasia in a bladder tumor model. To this end, we used the T24M bladder cancer cell line, previously generated from our studies, and developed a disease progression model in immunosuppressed mice, that can recapitulate the molecular events of bladder carcinogenesis. Our results documented that AF-MSCs exhibited high motility, when migrated either to T24M cells or to T24M-conditioned medium, and we further identified and studied the secreted factors which may trigger these enhanced migratory properties. Further, lentivirus-transduced AF-MSCs, expressing green fluorescent protein (GFP) or IFNβ, were intravenously administered to T24M tumor-bearing animals at multiple doses to examine their therapeutic effect. GFP- and IFNβ-AF-MSCs successfully migrated and colonized at the tumor site. Notably, significant inhibition of tumor growth as well as prolonged survival of mice were observed in the presence of IFNβ-AF-MSCs. Collectively, these results document the great potential of AF-MSCs as anti-cancer vehicles, implemented by the targeting of the tumor site and further facilitated by their high proliferation rate and expansion efficiency in culture.

OCT4 spliced variant OCT4B1 is expressed in human colorectal cancer

OCT4, a POU-domain transcription factor is considered to be a key factor in maintaining the pluripotency of stem cells. Several OCT4 isoforms are differentially expressed in human pluripotent and non-pluripotent cells. Reactivation of OCT4 expression is postulated to occur in differentiated cells that have undergone tumorigenesis. To examine OCT4 expression in colorectal cancer (CRC) tissues, and to assess the efficacy of OCT4 as a potential biomarker for CRC, in this study, we investigated its expression in CRC tissues, evaluated its relationship to various clinicopathological parameters and defined the isoform of OCT4 that was found to be expressed in CRC cases. Primary tumor tissues and matching adjacent non-cancerous tissues were obtained from 84 CRC patients. OCT4 expression and isoform determination were documented by reverse transcription-PCR and real-time PCR. OCT4, Sox-2, and NANOG localization were performed using immunohistochemistry. The isoforms expressed in the studied cases were confirmed by sequencing. Twenty biopsy specimens representing healthy tissues, retrieved from colonoscopy were studied in parallel as controls. OCT4 expression levels were higher in CRC tissues compared to matching, adjacent non-cancerous tissues, and healthy controls. Additionally, the levels of OCT4 expression in CRC tissues correlated with tumor stage. OCT4 and Sox-2 were localized in the nuclei and the cytoplasm of CRC cells. In all CRC cases, we found that the OCT4B1 isoform is expressed. Over-expression of OCT4B1 was found in poorly and moderately differentiated CRC tissues. In conclusion, the data imply that OCT4B1 isoform may represent a potential biomarker for the initiation, progression, and differentiation of CRC.

Gestational diabetes mellitus shares polymorphisms of genes associated with insulin resistance and type 2 diabetes in the Greek population

Gestational diabetes mellitus (GDM) and type 2 diabetes (T2D) share common pathophysiological features, including β-cell dysfunction and insulin resistance. In this study, we investigated the association between GDM and five recently identified T2D susceptibility loci, in a Greek population. We studied 148 women with GDM and 107 non-diabetic unrelated pregnant Greek women, for polymorphisms in the TCF7L2 gene (rs7903146 C/T), the PPARG gene (Pro12Ala), the KCNJ11 gene (E23K), the IRS1 gene (G972R) and in the FOXC2 gene (-512C>T). The T-allele of the TCF7L2 rs7903146 (C/T) polymorphism was found to be significantly associated with an increased risk of GDM [p = 0.0003; odds ratio (OR) 2.04 (95%CI 1.38-3.00)]. Additionally, CT and TT genotypes were significantly overrepresented in women with GDM compared to controls (p = 0.0003 and p = 0.0148, respectively). Analysis of the IRS1 G972R polymorphism showed that the R-allele frequency was increased in women with GDM [(p = 0.009; OR 1.67 (95%CI 1.14-2.47)]. The genotypes and allele frequencies of the other polymorphisms studied did not statistically differ between the GDM and the control women. Thus, our data suggest that the common T2D susceptibility polymorphism of TCF7L2 (rs7903146 C/T) gene, and the G972R polymorphism of the IRS1 gene, seem to predispose to GDM in Greek women.

Major challenges for gene therapy of thalassemia and sickle cell disease

Gene therapy utilizing retroviral vectors is being postulated as a real therapeutic alternative for many hemopoietic inherited diseases, such as β-thalassemia or sickle cell disease. A major limitation of current vectors is their inability to achieve efficient gene transfer into quiescent cells, such as human CD34+ cells that reside in the Go phase of the cell cycle and are highly enriched in hemopoietic stem cells. For that reason, lentiviral vectors (LVs) were proven to be more efficient than oncoretroviral vectors. Additional problems of these vectors are a) the low titers observed due to regulatory elements of the β-globin locus, used for the improvement of the transgene's expression b) the eventual silencing of the transgene and c) the toxicity posed on CD34+ cells due to the usage of VSV-G as an envelope protein. These facts hamper their application for gene therapy of hematopoietic cells. Thus, the major current drawbacks of the field affecting therapeutic efficacy, include 1) insufficient transduction efficiency of the target hemopoietic stem cells, 2) inconsistent expression of the transgene, 3) putative aberrant expression near integration sites raising safety issues and 4) lack of long term expression of the transgene exhibiting eventual silencing. This review presents the current status of globin gene therapy for the hemoglobin disorders, reviews the recent results and discusses how the knowledge gained from these trials can be used to develop a safe and effective gene therapy approach for the treatment of β-thalassemia and SCD.

Meta-analysis identifies 29 additional ulcerative colitis risk loci, increasing the number of confirmed associations to 47

Genome-wide association studies and candidate gene studies in ulcerative colitis have identified 18 susceptibility loci. We conducted a meta-analysis of six ulcerative colitis genome-wide association study datasets, comprising 6,687 cases and 19,718 controls, and followed up the top association signals in 9,628 cases and 12,917 controls. We identified 29 additional risk loci (P < 5 × 10(-8)), increasing the number of ulcerative colitis-associated loci to 47. After annotating associated regions using GRAIL, expression quantitative trait loci data and correlations with non-synonymous SNPs, we identified many candidate genes that provide potentially important insights into disease pathogenesis, including IL1R2, IL8RA-IL8RB, IL7R, IL12B, DAP, PRDM1, JAK2, IRF5, GNA12 and LSP1. The total number of confirmed inflammatory bowel disease risk loci is now 99, including a minimum of 28 shared association signals between Crohn's disease and ulcerative colitis.

Meta-analysis identifies 29 additional ulcerative colitis risk loci, increasing the number of confirmed associations to 47

Genome-wide association studies (GWAS) and candidate gene studies in ulcerative colitis (UC) have identified 18 susceptibility loci. We conducted a meta-analysis of 6 UC GWAS, comprising 6,687 cases and 19,718 controls, and followed-up the top association signals in 9,628 cases and 12,917 controls. We identified 29 additional risk loci (P<5×10^-8), increasing the number of UC associated loci to 47. After annotating associated regions using GRAIL, eQTL data and correlations with non-synonymous SNPs, we identified many candidate genes providing potentially important insights into disease pathogenesis, including IL1R2, IL8RA/B, IL7R, IL12B, DAP, PRDM1, JAK2, IRF5, GNA12 and LSP1. The total number of confirmed inflammatory bowel disease (IBD) risk loci is now 99, including a minimum of 28 shared association signals between Crohn’s disease (CD) and UC.

Variable effects of maternal and paternal-fetal contribution to the risk for preeclampsia combining GSTP1, eNOS, and LPL gene polymorphisms

Objective

To evaluate the maternal, paternal, and fetal genotype contribution to preeclampsia.

Study design, materials, and methods

We combined the analysis of polymorphisms of the GSTP1, eNOS, and LPL genes – affecting biotransformation enzymes and endothelial function – in a cohort of 167 preeclamptic and normal control trios (mother, father, and child) comprising a total of 501 samples in the Greek population, never analyzed before by this approach.

Results

For the frequency of the GSTP1 Ile¹⁰⁵/Val¹⁰⁵, the eNOS Glu298Asp and the LPL-93 polymorphisms, statistically significant differences were found between the two groups. However, the transmission rates of the parental alleles to neonates studied by the transmission disequilibrium test, disclosed no increased rate of transmission to preeclampsia children for the variant alleles of Val¹⁰⁵ GSTP1, 298Asp eNOS, and -93G LPL.

Conclusions

These novel data, suggest that interaction of all three types of genotypes (mother, father and neonate), reveals no effects on the development of preeclampsia, but provide the impetus for further studies to decipher the individual contribution of each genetic parameter of preeclampsia.

Maternal and fetal circulating sKL and ET-1 levels as function of normal labor at term

OBJECTIVES

To determine whether labor is associated with alterations of the levels of soluble c-kit ligand (sKL) and endothelin-1 (ET-1) in maternal plasma and umbilical cord blood.

METHODS

The sKL and ET-1 levels were investigated in umbilical cord and maternal plasma on the day of delivery in 18 pregnant women with vaginal delivery during labor, 18 non-pregnant women and 9 pregnant women before cesarean delivery, using an ELISA assay.

RESULTS

Umbilical cord plasma sKL levels were significantly higher than the maternal plasma in both types of delivery (p = 0.0001, p < 0.0001, respectively). However, maternal plasma ET-1 levels in the presence of labor were significantly higher than the cesarean delivery group (p < 0.0001). No difference was noted for sKL and ET-1 in umbilical cord vessels of both groups. Furthermore, a highly significant inverse correlation was documented between the individual levels of cord plasma ET-1 and the levels of cord plasma sKL (r = -0.6269, p = 0.0054).

CONCLUSIONS

The sKL levels found in umbilical cord plasma are consistent with the pleiotropic effects of sKL in facilitating the transition of the fetus to the neonatal stage. The reduced ET-1 maternal plasma levels, compared to non-pregnant women, probably are indicative of a putative mechanism for embryo protection from vasoconstriction sequelae. This assumption is strengthened by the corresponding ET-1 levels in umbilical cord plasma.

Thiopurine S-methyltransferase genotype and the use of thiopurines in paediatric inflammatory bowel disease Greek patients

BACKGROUND AND OBJECTIVE

Azathioprine (AZA) and 6-mercaptopurine (6MP) are used in the treatment of paediatric inflammatory bowel disease (IBD). Genetic variations in thiopurine S-methyltranfarase (TPMT) gene have been correlated with enzyme activity and with the occurrence of adverse events to AZA and 6MP. The aim of the present study was to investigate the frequency of the functional TPMT polymorphisms and their association with the occurrence of adverse events during azathioprine therapy in a paediatric IBD cohort.

METHODS

Ninety-seven thiopurine-treated paediatric IBD patients (41.24% boys and 58.76% girls) with a mean age 11.25 years (range 3-16), were assessed for TPMT polymorphisms and adverse events.

RESULTS

Of the 97 patients enrolled in the study, 18 (18.56%) were heterozygous mutated; two (2.06%) were homozygous for a mutated TPMT gene. Ten patients (10.31%) developed adverse effects, and four of them (40%) had one of the variant alleles.

CONCLUSIONS

In this small cohort of subjects, no association was found between TPMT polymorphisms and the occurrence of thiopurines-related adverse events.