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Dive into the research topics where Ivan V. Litvinov is active.

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Featured researches published by Ivan V. Litvinov.


Clinical Research in Cardiology | 2009

Iatrogenic epinephrine-induced reverse Takotsubo cardiomyopathy: direct evidence supporting the role of catecholamines in the pathophysiology of the “broken heart syndrome”

Ivan V. Litvinov; Mark A. Kotowycz; Sven Wassmann

Sirs Stress-induced transient cardiomyopathy (also known as Takotsubo cardiomyopathy) has been recognized as a disease entity since 1991 and accounts for 1% of acute coronary syndromes (ACS) that present with elevated cardiac biomarkers [1, 2]. About 80% of Takotsubo cardiomyopathy occurs in postmenopausal women [3]. The diagnosis depends on four criteria: (1) ST-segment changes or Twave inversions on the electrocardiogram, (2) transient wall motion abnormalities that are often inconsistent with coronary anatomy, (3) absence of obstructive coronary artery disease or evidence of acute plaque rupture, and (4) absence of significant head trauma, intracranial hemorrhage, pheochromocytoma, or other causes of myocardial dysfunction [3, 4]. The cardiomyopathy can be classified into a left ventricular (LV) apical ballooning variant (classic Takotsubo cardiomyopathy—most common), an inverted or reverse Takotsubo variant (basal akinesis with hyperdynamic apex), or a midventricular Takotsubo variant. The condition is often associated with catastrophic life events and severe psychological or physical stress. Due to this association with psychological stress, the cardiomyopathy is often referred to as the ‘‘Broken Heart Syndrome’’. Although the pathophysiology of stress-induced cardiomyopathy is not fully understood, it is thought that intense psychological or physical stress results in a catecholamine surge that adversely affects myocardial contractility, where postmenopausal women appear to be at a higher risk for developing the disease. The evidence for this was obtained from observational and case-control studies that have found an association between elevated catecholamine levels and disease onset [1, 4, 9]. In this paper, we present a case of iatrogenic epinephrine-induced reverse Takotsubo cardiomyopathy in a young 24-year-old female with no previous history of cardiac disease. While this case is unfortunate, it provides a unique opportunity to observe the triggering of stress-induced transient cardiomyopathy and provides evidence to support the role of epinephrine in the pathogenesis of this disease.


Clinical Cancer Research | 2010

Transcriptional Profiles Predict Disease Outcome in Patients with Cutaneous T-Cell Lymphoma

Ivan V. Litvinov; David A. Jones; Denis Sasseville; Thomas S. Kupper

Purpose: Average survival of cutaneous T-cell lymphoma (CTCL) is associated with clinical stage at diagnosis, where stage I has a favorable survival prognosis, whereas patients with more advanced stages succumb to their disease within 5 years. Although the majority of patients present with an early-stage CTCL, 15% to 20% of them will inevitably progress. Current state-of-the-art clinical criteria cannot identify individuals with stage I disease who are at risk of progression. The purpose of the current work is to gain novel molecular insight into the pathophysiology of CTCL to be able to identify patients with poor versus favorable prognosis. Our previous work used microarray analysis of skin biopsies from 62 CTCL patients to perform an unsupervised analysis of gene expression, which revealed three distinct transcription profile clusters. Experimental Design: In the present study, we used reverse transcription-PCR to confirm gene expression levels for a subset of representative genes in each cluster. We also performed a Kaplan-Meier analysis of survival and disease progression based on the 6 years of clinical follow-up. Results: Our reverse transcription-PCR results confirmed the upregulation of representative genes for each cluster, whereas clinical analysis documents that all stage I cases that progressed to stage II and beyond were in poor and intermediate prognosis clusters 1 and 3 and none were in favorable prognosis cluster 2. This analysis also identified certain genes that were preferentially expressed in favorable (e.g., WIF-1) versus poor (e.g., IL-17F) prognosis clusters. Conclusion: This work suggests that it may be possible to stratify CTCL patients into low-risk, intermediate-risk, and high-risk groups based on gene expression. Clin Cancer Res; 16(7); 2106–14. ©2010 AACR.


Blood | 2013

Elucidating the role of interleukin-17F in cutaneous T-cell lymphoma

Thorbjørn Krejsgaard; Ivan V. Litvinov; Yang Wang; Lixin Xia; Andreas Willerslev-Olsen; Sergei B. Koralov; Katharina L. Kopp; Charlotte M. Bonefeld; Mariusz A. Wasik; Carsten Geisler; Anders Woetmann; Youwen Zhou; Denis Sasseville; Niels Ødum

Inappropriately regulated expression of interleukin (IL)-17A is associated with the development of inflammatory diseases and cancer. However, little is known about the role of other IL-17 family members in carcinogenesis. Here, we show that a set of malignant T-cell lines established from patients with cutaneous T-cell lymphoma (CTCL) spontaneously secrete IL-17F and that inhibitors of Janus kinases and Signal transducer and activator of transcription 3 are able to block that secretion. Other malignant T-cell lines produce IL-17A but not IL-17F. Upon activation, however, some of the malignant T-cell lines are able to coexpress IL-17A and IL-17F, leading to formation of IL-17A/F heterodimers. Clinically, we demonstrate that IL-17F messenger RNA expression is significantly increased in CTCL skin lesions compared with healthy donors and patients with chronic dermatitis. IL-17A expression is also increased and a significant number of patients express high levels of both IL-17A and IL-17F. Concomitantly, we observed that the expression of the IL-17 receptor is significantly increased in CTCL skin lesions compared with control subjects. Importantly, analysis of a historic cohort of 60 CTCL patients indicates that IL-17F expression is associated with progressive disease. These findings implicate IL-17F in the pathogenesis of CTCL and suggest that IL-17 cytokines and their receptors may serve as therapeutic targets.


Cell Cycle | 2014

Deregulation in STAT signaling is important for cutaneous T-cell lymphoma (CTCL) pathogenesis and cancer progression.

Elena Netchiporouk; Ivan V. Litvinov; Linda Moreau; Martin Gilbert; Denis Sasseville; Madeleine Duvic

Deregulation of STAT signaling has been implicated in the pathogenesis for a variety of cancers, including CTCL. Constitutive activation of STAT5 and STAT3 was observed in early and late stages of CTCL, respectively. In early stages, IL-2, IL-7 and IL-15 signaling via JAK1 and JAK3 kinases is believed to be responsible for activating STAT5, while in advanced stages development of IL-21 autocrine signaling is thought to be important for STAT3 activation. Recent molecular evidence further suggests that upregulation of STAT5 in early disease stages results in increased expression of oncogenic miR-155 microRNA that subsequently targets STAT4 expression on mRNA level. STAT4 signaling is known to be critical for T helper (Th) 1 phenotype differentiation and its loss results in a switch from Th1 to Th2 phenotype in malignant T cells. During this switch the expression of STAT6 is often upregulated in CTCL. In advanced stages, activation of STAT3 and STAT5 may become completely cytokine-independent and be driven only via constitutively active JAK1 and JAK3 kinases. Further research into the molecular pathogenesis of JAK/STAT signaling in this cancer may enable us to develop effective therapies for our patients.


Clinical Cancer Research | 2015

The Use of Transcriptional Profiling to Improve Personalized Diagnosis and Management of Cutaneous T-cell Lymphoma (CTCL)

Ivan V. Litvinov; Elena Netchiporouk; Brendan Cordeiro; Marc-André Doré; Linda Moreau; Kevin Pehr; Martin Gilbert; Youwen Zhou; Denis Sasseville; Thomas S. Kupper

Purpose: Although many patients with mycosis fungoides presenting with stage I disease enjoy an indolent disease course and normal life expectancy, about 15% to 20% of them progress to higher stages and most ultimately succumb to their disease. Currently, it is not possible to predict which patients will progress and which patients will have a stable disease. Previously, we conducted microarray analyses with RT-PCR validation of gene expression in biopsy specimens from 60 patients with stage I–IV cutaneous T-cell lymphoma (CTCL), identified three distinct clusters based upon transcription profile, and correlated our molecular findings with 6 years of clinical follow-up. Experimental Design: We test by RT-PCR within our prediction model the expression of about 240 genes that were previously reported to play an important role in CTCL carcinogenesis. We further extend the clinical follow-up of our patients to 11 years. We compare the expression of selected genes between mycosis fungoides/Sézary syndrome and benign inflammatory dermatoses that often mimic this cancer. Results: Our findings demonstrate that 52 of the about 240 genes can be classified into cluster 1–3 expression patterns and such expression is consistent with their suggested biologic roles. Moreover, we determined that 17 genes (CCL18, CCL26, FYB, T3JAM, MMP12, LEF1, LCK, ITK, GNLY, IL2RA, IL26, IL22, CCR4, GTSF1, SYCP1, STAT5A, and TOX) are able to both identify patients who are at risk of progression and also distinguish mycosis fungoides/Sézary syndrome from benign mimickers. Conclusions: This study, combined with other gene expression analyses, prepares the foundation for the development of personalized molecular approach toward diagnosis and treatment of CTCL. Clin Cancer Res; 21(12); 2820–9. ©2015 AACR.


Experimental Dermatology | 2011

CD109 release from the cell surface in human keratinocytes regulates TGF‐β receptor expression, TGF‐β signalling and STAT3 activation: relevance to psoriasis

Ivan V. Litvinov; Albane Bizet; Yousef Binamer; David A. Jones; Denis Sasseville; Anie Philip

Abstract:  Transforming growth factor (TGF)‐β is an important cytokine that negatively regulates keratinocyte proliferation. Deregulation of TGF‐β signalling has been reported in psoriasis, where despite increased expression of TGF‐β, psoriatic keratinocytes continue to hyperproliferate. Recently, we have identified CD109, a glycosyl phosphatidylinositol (GPI)‐anchored protein, as a novel co‐receptor and negative regulator of TGF‐β signalling. In the current work, we demonstrate that release of CD109 from the cell surface or the addition of CD109 protein results in downregulation of TGF‐β signalling and TGF‐β receptor expression in human keratinocytes. Moreover, these effects are associated with an increase in phospho‐STAT3 levels, enhanced total STAT3 and Bcl‐2 expression and an increase in cell growth and survival, suggesting that released/soluble CD109 is able to induce molecular changes that are known to occur in psoriasis. Analysis of CD109 expression in psoriasis patients reveals that CD109 protein expression is markedly decreased in psoriatic epidermis as compared to adjacent uninvolved skin. In contrast, CD109 mRNA expression is unchanged in psoriatic plaques in comparison with normal skin. This raises a possibility that CD109 protein release is enhanced in psoriatic keratinocytes. Furthermore, psoriatic epidermis displays decreased expression of TGF‐β receptors, consistent with the results obtained in vitro in keratinocytes with CD109 release or addition of CD109 recombinant protein. Together our findings suggest that aberrant CD109 release from the cell surface in human keratinocytes may induce molecular changes that are usually observed in psoriasis and may explain TGF‐β receptor downregulation and decrease in TGF‐β signalling in psoriasis.


Experimental Hematology | 2011

CD109 release from the cell surface in human keratinocytes regulates TGF-β receptor expression, TGF-β signalling and STAT3 activation: relevance to psoriasis.

Ivan V. Litvinov; Yousef Binamer; Denis Sasseville; Anie Philip; Walton D. Jones; Albane A. Bizet

Abstract:  Transforming growth factor (TGF)‐β is an important cytokine that negatively regulates keratinocyte proliferation. Deregulation of TGF‐β signalling has been reported in psoriasis, where despite increased expression of TGF‐β, psoriatic keratinocytes continue to hyperproliferate. Recently, we have identified CD109, a glycosyl phosphatidylinositol (GPI)‐anchored protein, as a novel co‐receptor and negative regulator of TGF‐β signalling. In the current work, we demonstrate that release of CD109 from the cell surface or the addition of CD109 protein results in downregulation of TGF‐β signalling and TGF‐β receptor expression in human keratinocytes. Moreover, these effects are associated with an increase in phospho‐STAT3 levels, enhanced total STAT3 and Bcl‐2 expression and an increase in cell growth and survival, suggesting that released/soluble CD109 is able to induce molecular changes that are known to occur in psoriasis. Analysis of CD109 expression in psoriasis patients reveals that CD109 protein expression is markedly decreased in psoriatic epidermis as compared to adjacent uninvolved skin. In contrast, CD109 mRNA expression is unchanged in psoriatic plaques in comparison with normal skin. This raises a possibility that CD109 protein release is enhanced in psoriatic keratinocytes. Furthermore, psoriatic epidermis displays decreased expression of TGF‐β receptors, consistent with the results obtained in vitro in keratinocytes with CD109 release or addition of CD109 recombinant protein. Together our findings suggest that aberrant CD109 release from the cell surface in human keratinocytes may induce molecular changes that are usually observed in psoriasis and may explain TGF‐β receptor downregulation and decrease in TGF‐β signalling in psoriasis.


Blood | 2016

Staphylococcal enterotoxin A (SEA) stimulates STAT3 activation and IL-17 expression in cutaneous T-cell lymphoma

Andreas Willerslev-Olsen; Thorbjørn Krejsgaard; Lise M. Lindahl; Ivan V. Litvinov; Simon Fredholm; David L. Petersen; Claudia Nastasi; Robert Gniadecki; Nigel P. Mongan; Denis Sasseville; Mariusz A. Wasik; Charlotte M. Bonefeld; Carsten Geisler; Anders Woetmann; Lars Iversen; Mogens Kilian; Sergei B. Koralov; Niels Ødum

Cutaneous T-cell lymphoma (CTCL) is characterized by proliferation of malignant T cells in a chronic inflammatory environment. With disease progression, bacteria colonize the compromised skin barrier and half of CTCL patients die of infection rather than from direct organ involvement by the malignancy. Clinical data indicate that bacteria play a direct role in disease progression, but little is known about the mechanisms involved. Here, we demonstrate that bacterial isolates containing staphylococcal enterotoxin A (SEA) from the affected skin of CTCL patients, as well as recombinant SEA, stimulate activation of signal transducer and activator of transcription 3 (STAT3) and upregulation of interleukin (IL)-17 in immortalized and primary patient-derived malignant and nonmalignant T cells. Importantly, SEA induces STAT3 activation and IL-17 expression in malignant T cells when cocultured with nonmalignant T cells, indicating an indirect mode of action. In accordance, malignant T cells expressing an SEA-nonresponsive T-cell receptor variable region β chain are nonresponsive to SEA in monoculture but display strong STAT3 activation and IL-17 expression in cocultures with SEA-responsive nonmalignant T cells. The response is induced via IL-2 receptor common γ chain cytokines and a Janus kinase 3 (JAK3)-dependent pathway in malignant T cells, and blocked by tofacitinib, a clinical-grade JAK3 inhibitor. In conclusion, we demonstrate that SEA induces cell cross talk-dependent activation of STAT3 and expression of IL-17 in malignant T cells, suggesting a mechanism whereby SEA-producing bacteria promote activation of an established oncogenic pathway previously implicated in carcinogenesis.


Cancer Medicine | 2015

Demographic patterns of cutaneous T-cell lymphoma incidence in Texas based on two different cancer registries

Ivan V. Litvinov; Michael T. Tetzlaff; Elham Rahme; Michelle A. Jennings; David R. Risser; Pamela Gangar; Elena Netchiporouk; Linda Moreau; Victor G. Prieto; Denis Sasseville; Madeleine Duvic

Cutaneous T‐cell lymohomas (CTCLs) are rare, but potentially devastating malignancies, with Mycosis fungoides and Sézary Syndrome being the most common. In our previous study, we identified and described regions of geographic clustering of CTCL cases in Texas by analyzing ~1990 patients using two distinct cancer registries. In the current work, we describe in detail demographic patterns for this malignancy in our study population and apply logistic regression models to analyze the incidence of CTCL by sex, race, age, and clinical stage at the time of diagnosis. Furthermore, using Fishers exact test, we analyze changes in incidence over time in the identified Houston communities with unusually high CTCL incidence. While CTCL primarily affects Caucasian individuals >55 years old, we confirm that it presents at a younger age and with more advanced disease stages in African‐American and Hispanic individuals. Also, we demonstrate a significant increase in CTCL incidence over time in the identified communities. Spring, Katy, and Houston Memorial areas had high baseline rates. Furthermore, a statistically significant disease surge was observed in these areas after ~2005. This report supplements our initial study documenting the existence of geographic clustering of CTCL cases in Texas and in greater detail describes demographic trends for our patient population. The observed surge in CTCL incidence in the three identified communities further argues that this malignancy may be triggered by one or more external etiologic agents.


OncoImmunology | 2014

Ectopic expression of embryonic stem cell and other developmental genes in cutaneous T-cell lymphoma

Ivan V. Litvinov; Elena Netchiporouk; Brendan Cordeiro; Hanieh Zargham; Kevin Pehr; Martin Gilbert; Youwen Zhou; Linda Moreau; Anders Woetmann; Niels Ødum; Thomas S. Kupper; Denis Sasseville

Cutaneous T-cell lymphoma (CTCL) is a potentially devastating malignancy. The pathogenesis of this cancer remains poorly elucidated. Previous studies focused on analysis of expression and function of known oncogenes and tumor suppressor genes. However, emerging reports highlight that it is also important to analyze the expression of genes that are ectopically expressed in CTCL (e.g., embryonic stem cell genes (ESC), cancer testis (CT) genes, etc.). Currently, it is not known whether ESC genes are expressed in CTCL. In the current work, we analyze by RT-PCR the expression of 26 ESC genes, many of which are known to regulate pluripotency and promote cancer stem cell-like phenotype, in a historic cohort of 60 patients from Boston and in a panel of 11 patient-derived CTCL cell lines and compare such expression to benign inflammatory dermatoses that often clinically mimic CTCL. Our findings document that many critical ESC genes including NANOG, SOX2, OCT4 (POU5F1) and their upstream and downstream signaling members are expressed in CTCL. Similarly, polycomb repressive complex 2 (PRC2) genes (i.e., EZH2, EED, and SUZ12) are also expressed in CTCL lesional skin. Furthermore, select ESC genes (OCT4, EED, TCF3, THAP11, CHD7, TIP60, TRIM28) are preferentially expressed in CTCL samples when compared to benign skin biopsies. Our work suggests that ESC genes are ectopically expressed together with CT genes, thymocyte development genes and B cell-specific genes and may be working in concert to promote tumorigenesis. Specifically, while ESC genes may be promoting cancer stem cell-like phenotype, CT genes may be contributing to aneuploidy and genomic instability by producing aberrant chromosomal translocations. Further analysis of ESC expression and function in this cancer will greatly enhance our fundamental understanding of CTCL and will help us identify novel therapeutic targets.

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Niels Ødum

University of Copenhagen

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Linda Moreau

McGill University Health Centre

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Youwen Zhou

University of British Columbia

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Kevin Pehr

Ottawa Hospital Research Institute

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