Phase 1/2 randomized, placebo-control trial of palifermin to prevent graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation (HSCT)

Pathophysiology of gastrointestinal acute graft-versus-host disease and the potential role of glucagon-like peptide 2

Acute graft-versus-host disease (aGVHD) is a life-threatening complication after allogeneic haematopoietic cell transplantation, with gastrointestinal (GI) tract involvement (GI aGVHD) being one of the leading causes of morbidity and mortality. Whilst systemic steroids are the standard first-line treatment for aGVHD, approximately 50% of patients become steroid refractory (SR), which is associated with poor outcomes. Existing options for SR-GVHD are limited, and there is a significant unmet need for new non-immunosuppressive treatment approaches in patients with GI aGVHD. Here, we review newer concepts in the pathogenesis of GI aGVHD and present the evidence for the role of glucagon-like peptide 2 (GLP-2) in maintaining and protecting GI epithelial cells, including the enterocytes, intestinal stem cells and Paneth cells, which are direct targets of aGVHD. Finally, we discuss the therapeutic rationale for GLP-2 treatment as a tissue regeneration approach and the potential use of the novel GLP-2 analogue apraglutide as an adjunctive treatment for GI aGVHD.

Title: Chemotherapy-Induced Oral Complications and Prophylaxis Strategies

Cancer is currently a significant therapeutic challenge and is frequently connected with numerous adverse effects. Despite many improvements in chemotherapy, oral complications are common, leading to poor quality of life and chemotherapeutic dose reduction, which impair survival. This review summarizes the most common dental complications in patients receiving chemotherapy. We mainly focus on oral mucositis as it is a major cause of dose-limiting toxicity. Furthermore, oral candidiasis, viral infections, and xerostomia will be discussed. Conclusions: preventing complications is significantly more important than treating them. All patients beginning systemic anticancer treatment should undergo a thorough oral examination and get appropriate prophylaxis.

Methylene blue for intractable pain from oral mucositis related to cancer treatment: a randomized phase 2 clinical trial

BACKGROUND

Oral mucositis (OM) in patients receiving cancer therapy is thus far not well managed with standard approaches. We aimed to assess the safety and effectiveness of methylene blue (MB) oral rinse for OM pain in patients receiving cancer therapy.

METHODS

In this randomized, single-blind phase 2 clinical trial, patients were randomized to one of four arms: MB 0.025%+conventional therapy (CTx) (n = 15), MB 0.05%+CTx (n = 14), MB 0.1%+CTx (n = 15), or CTx alone (n = 16). Intervention groups received MB oral rinse every 6 h for 2 days with outcomes measured at days 1-2; safety was evaluated up to 30 days. The primary outcome measured change in the pain numeric rating scale (0-10) from baseline to day 2. Secondary outcome measured change in oral function burden scores from baseline to day 2, World Health Organization OM grades, morphine equivalent daily doses, and adverse events. The trial was registered with ClinicalTrials.gov ID: NCT03469284.

RESULTS

Sixty patients (mean age 43, range 22-62 years) completed the study. Compared with those who received CTx alone, those who received MB had a significant reduction of pain scores at day 2 of treatment (mean ± SD); 0.025%: 5.2 ± 2.9, 0.05%: 4.5 ± 2.9, 0.1%: 5.15 ± 2.6) and reduction of oral function burden scores (0.025%: 2.5 ± 1.55, 0.05%: 2.8 ± 1.7, 0.1%: 2.9 ± 1.60). No serious adverse events were noted, but eight patients reported burning sensation of the oral cavity with the first dose, and this caused one patient to discontinue therapy.

CONCLUSIONS

MB oral rinse showed significant pain reduction and improved oral functioning with minimal adverse effects.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT03469284.

GVHD, IBD and primary immunodeficiencies: The gut as a target of immunopathology resulting from impaired immunity

The intestinal tract is the largest immunological organ in the body and has a central function of regulating local immune responses, as the intestinal epithelial barrier is a location where the immune system interacts with the gut microbiome including bacteria, fungi and viruses. Impaired immunity in the intestinal tract can lead to immunopathology, which manifests in different diseases such as inflammatory bowel disease (IBD) or intestinal graft-versus-host disease (GVHD). A disturbed communication between epithelial cells, immune cells and microbiome will shape pathogenic immune responses to antigens, which need to be counterbalanced by tolerogenic mechanisms and repair mechanisms. Here, we review how impaired intestinal immune function leads to immunopathology with a specific focus on innate immune cells, the role of the microbiome and the resulting clinical manifestations including intestinal GVHD, IBD and enteropathy in primary immunodeficiency. This article is protected by copyright. All rights reserved.

Challenges and opportunities targeting mechanisms of epithelial injury and recovery in acute intestinal graft-versus-host disease

Despite advances in immunosuppressive prophylaxis and overall supportive care, gastrointestinal (GI) graft-versus-host disease (GVHD) remains a major, lethal side effect after allogeneic hematopoietic stem cell transplantation (allo-HSCT). It has become increasingly clear that the intestinal epithelium, in addition to being a target of transplant-related toxicity and GVHD, plays an important role in the onset of GVHD. Over the last two decades, increased understanding of the epithelial constituents and their microenvironment has led to the development of novel prophylactic and therapeutic interventions, with the potential to protect the intestinal epithelium from GVHD-associated damage and promote its recovery following insult. In this review, we will discuss intestinal epithelial injury and the role of the intestinal epithelium in GVHD pathogenesis. In addition, we will highlight possible approaches to protect the GI tract from damage posttransplant and to stimulate epithelial regeneration, in order to promote intestinal recovery. Combined treatment modalities integrating immunomodulation, epithelial protection, and induction of regeneration may hold the key to unlocking mucosal recovery and optimizing therapy for acute intestinal GVHD.

Novel Insights Into the Mechanism of GVHD-Induced Tissue Damage

Prophylaxis for and treatment of graft-versus-host disease (GVHD) are essential for successful allogeneic hematopoietic stem cell transplantation (allo-SCT) and mainly consist of immunosuppressants such as calcineurin inhibitors. However, profound immunosuppression can lead to tumor relapse and infectious complications, which emphasizes the necessity of developing novel management strategies for GVHD. Emerging evidence has revealed that tissue-specific mechanisms maintaining tissue homeostasis and promoting tissue tolerance to combat GVHD are damaged after allo-SCT, resulting in exacerbation and treatment refractoriness of GVHD. In the gastrointestinal tract, epithelial regeneration derived from intestinal stem cells (ISCs), a microenvironment that maintains healthy gut microbiota, and physical and chemical mucosal barrier functions against pathogens are damaged by conditioning regimens and/or GVHD. The administration of growth factors for cells that maintain intestinal homeostasis, such as interleukin-22 (IL-22) for ISCs, R-spondin 1 (R-Spo1) for ISCs and Paneth cells, and interleukin-25 (IL-25) for goblet cells, mitigates murine GVHD. In this review, we summarize recent advances in the understanding of GVHD-induced tissue damage and emerging strategies for the management of GVHD.

IFN-λ therapy prevents severe gastrointestinal graft-versus-host disease

Immunopathology and intestinal stem cell (ISC) loss in the gastrointestinal (GI) tract is the prima facie manifestation of graft-versus-host disease (GVHD) and is responsible for significant mortality after allogeneic bone marrow transplantation (BMT). Approaches to prevent GVHD to date focus on immune suppression. Here, we identify interferon-λ (IFN-λ; interleukin-28 [IL-28]/IL-29) as a key protector of GI GVHD immunopathology, notably within the ISC compartment. Ifnlr1-/- mice displayed exaggerated GI GVHD and mortality independent of Paneth cells and alterations to the microbiome. Ifnlr1-/- intestinal organoid growth was significantly impaired, and targeted Ifnlr1 deficiency exhibited effects intrinsic to recipient Lgr5+ ISCs and natural killer cells. PEGylated recombinant IL-29 (PEG-rIL-29) treatment of naive mice enhanced Lgr5+ ISC numbers and organoid growth independent of both IL-22 and type I IFN and modulated proliferative and apoptosis gene sets in Lgr5+ ISCs. PEG-rIL-29 treatment improved survival, reduced GVHD severity, and enhanced epithelial proliferation and ISC-derived organoid growth after BMT. The preservation of ISC numbers in response to PEG-rIL-29 after BMT occurred both in the presence and absence of IFN-λ-signaling in recipient natural killer cells. IFN-λ is therefore an attractive and rapidly testable approach to prevent ISC loss and immunopathology during GVHD.

Graft-versus-host disease: a disorder of tissue regeneration and repair

Regenerative failure at barrier surfaces and maladaptive repair leading to fibrosis are hallmarks of graft-versus-host disease (GVHD). Although immunosuppressive treatment can control inflammation, impaired tissue homeostasis leads to prolonged organ damage and impaired quality of life. In this Spotlight article, we review recent research that addresses the critical failures in tissue regeneration and repair that underpin treatment-resistant GVHD. We highlight current interventions designed to overcome these defects and provide our assessment of the future therapeutic landscape.

Repurposing a novel anti-cancer RXR agonist to attenuate murine acute GVHD and maintain graft-versus-leukemia responses

The nuclear receptor (NR) subclass, retinoid X receptors (RXRs), exert immunomodulatory functions that control inflammation and metabolism via homodimers and heterodimers, with several other NRs, including retinoic acid receptors. IRX4204 is a novel, highly specific RXR agonist in clinical trials that potently and selectively activates RXR homodimers, but not heterodimers. In this study, in vivo IRX4204 compared favorably with FK506 in abrogating acute graft-versus-host disease (GVHD), which was associated with inhibiting allogeneic donor T-cell proliferation, reducing T-helper 1 differentiation, and promoting regulatory T-cell (Treg) generation. Recipient IRX4204 treatment reduced intestinal injury and decreased IFN-γ and TNF-α serum levels. Transcriptional analysis of donor T cells isolated from intestines of GVHD mice treated with IRX4204 revealed significant decreases in transcripts regulating proinflammatory pathways. In vitro, inducible Treg differentiation from naive CD4+ T cells was enhanced by IRX4204. In vivo, IRX4204 increased the conversion of donor Foxp3- T cells into peripheral Foxp3+ Tregs in GVHD mice. Using Foxp3 lineage-tracer mice in which both the origin and current FoxP3 expression of Tregs can be tracked, we demonstrated that IRX4204 supports Treg stability. Despite favoring Tregs and reducing Th1 differentiation, IRX4204-treated recipients maintained graft-versus-leukemia responses against both leukemia and lymphoma cells. Notably, IRX4204 reduced in vitro human T-cell proliferation and enhanced Treg generation in mixed lymphocyte reaction cultures. Collectively, these beneficial effects indicate that targeting RXRs with IRX4204 could be a novel approach to preventing acute GVHD in the clinic.

A Prospective Cohort Study Comparing Long-Term Outcomes with and without Palifermin in Patients Receiving Hematopoietic Cell Transplantation for Hematologic Malignancies

The incidence of debilitating oral mucositis (OM) can be as high as 99% after myeloablative conditioning regimens preparing patients with hematologic malignancies for hematopoietic cell transplantation (HCT). Palifermin (KGF) is a recombinant human keratinocyte growth factor that reduces the incidence and duration of severe OM. The long-term safety of KGF has not been well established, however. In this long-term prospective matched-cohort study, patients who received KGF (cases) and underwent autologous or allogeneic HCT for hematologic malignancies between 2006 and 2013 were matched 1:1 to patients who did not receive KGF (controls). The primary outcome was overall survival (OS). Other outcomes were disease relapse, new malignancies, pancreatitis, renal failure requiring dialysis, pulmonary complications, cataract surgery, and acute and chronic graft-versus-host disease (GVHD). The analysis population comprised 2191 matched pairs with a wide range of diseases and donor types that received diverse conditioning and GVHD preventive regimens, representing contemporary practice patterns. The median duration of follow-up was 8 years (range, 1 to 12.5 years). In multivariate analyses, the probabilities of OS (relative risk [RR], 1.01; 95% confidence interval [CI], 0.91 to 1.12), relapse (RR, 1.06; 95% CI, 0.94 to 1.18), new malignancies (RR, 0.89; 95% CI, 0.67 to 1.18), and cataract surgery (RR, 1.05; 95% CI, 0.74 to 1.50) were not statistically significantly different between cases and controls. In univariate analyses, no increased risks were observed for renal failure requiring dialysis, pancreatitis, acute GVHD, chronic GVHD, interstitial pneumonitis/acute respiratory distress syndrome/idiopathic pneumonia syndrome, or bronchiolitis obliterans/cryptogenic organizing pneumonia/bronchiolitis obliterans organizing pneumonia among cases compared with controls. This long-term prospective safety cohort study demonstrates that the KGF group had no increased risk of overall mortality, relapse, new malignancies, or any other key outcome. The broad inclusion criteria allow the results to be generalized to contemporary practice for patients with a wide range of diseases and receiving a wide range of HCT conditioning regimens and graft sources from diverse donor types.

Insights from integrating clinical and preclinical studies advance understanding of graft-versus-host disease

As a result of impressive increases in our knowledge of rodent and human immunology, the understanding of the pathophysiologic mechanisms underlying graft-versus-host disease (GVHD) has dramatically improved in the past 15 years. Despite improved knowledge, translation to clinical care has not proceeded rapidly, and results from experimental models have been inconsistent in their ability to predict the clinical utility of new therapeutic agents. In parallel, new tools in immunology have allowed in-depth analyses of the human system and have recently been applied in the field of clinical GVHD. Notwithstanding these advances, there is a relative paucity of mechanistic insights into human translational research, and this remains an area of high unmet need. Here we review selected recent advances in both preclinical experimental transplantation and translational human studies, including new insights into human immunology, the microbiome, and regenerative medicine. We focus on the fact that both approaches can interactively improve our understanding of both acute and chronic GVHD biology and open the door to improved therapeutics and successes.

Glucagon-like peptide 2 for intestinal stem cell and Paneth cell repair during graft-versus-host disease in mice and humans

Acute graft-versus-host disease (GVHD) is a life-threatening complication after allogeneic hematopoietic cell transplantation (allo-HCT). Although currently used GVHD treatment regimens target the donor immune system, we explored here an approach that aims at protecting and regenerating Paneth cells (PCs) and intestinal stem cells (ISCs). Glucagon-like-peptide-2 (GLP-2) is an enteroendocrine tissue hormone produced by intestinal L cells. We observed that acute GVHD reduced intestinal GLP-2 levels in mice and patients developing GVHD. Treatment with the GLP-2 agonist, teduglutide, reduced de novo acute GVHD and steroid-refractory GVHD, without compromising graft-versus-leukemia (GVL) effects in multiple mouse models. Mechanistically GLP-2 substitution promoted regeneration of PCs and ISCs, which enhanced production of antimicrobial peptides and caused microbiome changes. GLP-2 expanded intestinal organoids and reduced expression of apoptosis-related genes. Low numbers of L cells in intestinal biopsies and high serum levels of GLP-2 were associated with a higher incidence of nonrelapse mortality in patients undergoing allo-HCT. Our findings indicate that L cells are a target of GVHD and that GLP-2-based treatment of acute GVHD restores intestinal homeostasis via an increase of ISCs and PCs without impairing GVL effects. Teduglutide could become a novel combination partner for immunosuppressive GVHD therapy to be tested in clinical trials.

The role of the thymus in allogeneic bone marrow transplantation and the recovery of the peripheral T-cell compartment

As the thymus represents the primary site of T-cell development, optimal thymic function is of paramount importance for the successful reconstitution of the adaptive immunity after allogeneic hematopoietic stem cell transplantation. Thymus involutes as part of the aging process and several factors, including previous chemotherapy treatments, conditioning regimen used in preparation to the allograft, occurrence of graft-versus-host disease, and steroid therapy that impair the integrity of the thymus, thus affecting its role in supporting T-cell neogenesis. Although the pathways governing its regeneration are still poorly understood, the thymus has a remarkable capacity to recover its function after damage. Measurement of both recent thymic emigrants and T-cell receptor excision circles is valuable tools to assess thymic output and gain insights on its function. In this review, we will extensively discuss available data on factors regulating thymic function after allogeneic hematopoietic stem cell transplantation, as well as the strategies and therapeutic approaches under investigation to promote thymic reconstitution and accelerate immune recovery in transplanted patients, including the use of cytokines, sex-steroid ablation, precursor T-cells, and thymus bioengineering. Although none of them is routinely used in the clinic, these approaches have the potential to enhance thymic function and immune recovery, not only in patients given an allograft but also in other conditions characterized by immune deficiencies related to a defective function of the thymus.

How to Make an Immune System and a Foreign Host Quickly Cohabit in Peace? The Challenge of Acute Graft-Versus-Host Disease Prevention After Allogeneic Hematopoietic Cell Transplantation

Allogeneic hematopoietic cell transplantation (alloHCT) has been used as cellular immunotherapy against hematological cancers for more than six decades. Its therapeutic efficacy relies on the cytoreductive effects of the conditioning regimen but also on potent graft-versus-tumor (GVT) reactions mediated by donor-derived immune cells. However, beneficial GVT effects may be counterbalanced by acute GVHD (aGVHD), a systemic syndrome in which donor immune cells attack healthy tissues of the recipient, resulting in severe inflammatory lesions mainly of the skin, gut, and liver. Despite standard prophylaxis regimens, aGVHD still occurs in approximately 20–50% of alloHCT recipients and remains a leading cause of transplant-related mortality. Over the past two decades, advances in the understanding its pathophysiology have helped to redefine aGVHD reactions and clinical presentations as well as developing novel strategies to optimize its prevention. In this review, we provide a brief overview of current knowledge on aGVHD immunopathology and discuss current approaches and novel strategies being developed and evaluated in clinical trials for aGVHD prevention. Optimal prophylaxis of aGVHD would prevent the development of clinically significant aGVHD, while preserving sufficient immune responsiveness to maintain beneficial GVT effects and immune defenses against pathogens.

Governmental Regulations and Increasing Food and Drug Administration Oversight of Regenerative Medicine Products: What's New in 2020?

The United States Food and Drug Administration (FDA) is responsible for protecting and promoting public health through rules and regulations. Over the past few years, the field of regenerative medicine and cell therapy have garnered significant interest, and this evolving new biology is changing fast and challenging regulatory bodies. The FDA has published a series of guidance documents outlining steps to protect consumers against potentially dangerous and unproven treatments. The agency has offered a grace period for "stem cell clinics" until November 2020 to come into compliance by obtaining Investigational New Drug applications and working to secure premarket approval of their products. With the documentation of hundreds of "stem cell clinics," the FDA needs to enforce the adherence to their outlined standards to protect patients. The aim of this review was to provide an overview of these FDA regulations and some current issues within the industry. The purpose is to educate and inform the musculoskeletal community about the current government regulations of this new expanding biology. LEVEL OF EVIDENCE: Level V, expert opinion.

Systematic review of growth factors and cytokines for the management of oral mucositis in cancer patients and clinical practice guidelines

PURPOSE

To update the clinical practice guidelines for the use of growth factors and cytokines for the prevention and/or treatment of oral mucositis (OM).

METHODS

A systematic review was conducted by the Mucositis Study Group of the Multinational Association of Supportive Care in Cancer/International Society of Oral Oncology (MASCC/ISOO). The body of evidence for each intervention, in each cancer treatment setting, was assigned an evidence level. The findings were added to the database used to develop the 2014 MASCC/ISOO clinical practice guidelines. Based on the evidence level, the following guidelines were determined: recommendation, suggestion, and no guideline possible.

RESULTS

A total of 15 new papers were identified within the scope of this section and were merged with 51 papers that were reviewed in the previous guidelines update. Of these, 14, 5, 13, 2, and 1 were randomized controlled trials about KGF-1, G-CSF, GM-CSF, EGF, and erythropoietin, respectively. For the remaining agents there were no new RCTs. The previous recommendation for intravenous KGF-1 in patients undergoing autologous hematopoietic stem cell transplantation (HSCT) conditioned with high-dose chemotherapy and TBI-based regimens is confirmed. The previous suggestion against the use of topical GM-CSF for the prevention of OM in the setting of high-dose chemotherapy followed by autologous or allogeneic stem cell transplantation remains unchanged.

CONCLUSIONS

Of the growth factors and cytokines studied for the management of OM, the evidence supports a recommendation in favor of KGF-1 and a suggestion against GM-CSF in certain clinical settings.

Inhibition of inositol kinase B controls acute and chronic graft-versus-host disease

T-cell activation releases inositol 1,4,5-trisphosphate (IP3), inducing cytoplasmic calcium (Ca2+) influx. In turn, inositol 1,4,5-trisphosphate 3-kinase B (Itpkb) phosphorylates IP3 to negatively regulate and thereby tightly control Ca2+ fluxes that are essential for mature T-cell activation and differentiation and protection from cell death. Itpkb pathway inhibition increases intracellular Ca2+, induces apoptosis of activated T cells, and can control T-cell-mediated autoimmunity. In this study, we employed genetic and pharmacological approaches to inhibit Itpkb signaling as a means of controlling graft-versus-host disease (GVHD). Murine-induced, Itpkb-deleted (Itpkb-/-) T cells attenuated acute GVHD in 2 models without eliminating A20-luciferase B-cell lymphoma graft-versus-leukemia (GVL). A highly potent, selective inhibitor, GNF362, ameliorated acute GVHD without impairing GVL against 2 acute myeloid leukemia lines (MLL-AF9-eGFP and C1498-luciferase). Compared with FK506, GNF362 more selectively deleted donor alloreactive vs nominal antigen-responsive T cells. Consistent with these data and as compared with FK506, GNF362 had favorable acute GVHD and GVL properties against MLL-AF9-eGFP cells. In chronic GVHD preclinical models that have a pathophysiology distinct from acute GVHD, Itpkb-/- donor T cells reduced active chronic GVHD in a multiorgan system model of bronchiolitis obliterans (BO), driven by germinal center reactions and resulting in target organ fibrosis. GNF362 treatment reduced active chronic GVHD in both BO and scleroderma models. Thus, intact Itpkb signaling is essential to drive acute GVHD pathogenesis and sustain active chronic GVHD, pointing toward a novel clinical application to prevent acute or treat chronic GVHD.

Keratinocyte growth factor impairs human thymic recovery from lymphopenia

BACKGROUND

The lymphocyte-depleting antibody alemtuzumab is a highly effective treatment of relapsing-remitting multiple sclerosis (RRMS); however 50% of patients develop novel autoimmunity post-treatment. Most at risk are individuals who reconstitute their T-cell pool by proliferating residual cells, rather than producing new T-cells in the thymus; raising the possibility that autoimmunity might be prevented by increasing thymopoiesis. Keratinocyte growth factor (palifermin) promotes thymopoiesis in non-human primates.

METHODS

Following a dose-tolerability sub-study, individuals with RRMS (duration ≤10 years; expanded disability status scale ≤5·0; with ≥2 relapses in the previous 2 years) were randomised to placebo or 180mcg/kg/day palifermin, given for 3 days immediately prior to and after each cycle of alemtuzumab, with repeat doses at M1 and M3. The interim primary endpoint was naïve CD4+ T-cell count at M6. Exploratory endpoints included: number of recent thymic-emigrants (RTEs) and signal-joint T-cell receptor excision circles (sjTRECs)/mL of blood. The trial primary endpoint was incidence of autoimmunity at M30.

FINDINGS

At M6, individuals receiving palifermin had fewer naïve CD4+T-cells (2.229x107/L vs. 7.733x107/L; p=0.007), RTEs (16% vs. 34%) and sjTRECs/mL (1100 vs. 3396), leading to protocol-defined termination of recruitment. No difference was observed in the rate of autoimmunity between the two groupsConclusion: In contrast to animal studies, palifermin reduced thymopoiesis in our patients. These results offer a note of caution to those using palifermin to promote thymopoiesis in other settings, particularly in the oncology/haematology setting where alemtuzumab is often used as part of the conditioning regime.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01712945Funding: MRC and Moulton Charitable Foundation.

Management of oral mucositis in pediatric patients receiving cancer therapy: A systematic review and meta-analysis

BACKGROUND

One of the most common complications of cancer chemotherapy is oral mucositis (OM). OM affects more than 75% of patients undergoing chemotherapy and represents a significant burden to patients and caregivers. We performed a systematic review and meta-analysis of published studies to investigate the effects of agents and techniques in reducing OM.

PROCEDURE

This systematic review investigated, critically appraised, and rated the evidence on agents used to manage OM in children undergoing cancer therapy. A comprehensive search of the relevant literature was performed from January 2006 to December 2017. MEDLINE, Scopus, the Cochrane Database of Systematic Reviews, EMBASE, and the Web of Science were searched. Nine eligible studies were identified. Using random-effects models, standardized mean difference was estimated between treated and control groups across all studies. The Cochran test and the I2 index were performed for heterogeneity between studies. The significance level was set at P = 0.05.

RESULTS

Palifermin reduced the incidence (OR = 4.131, P = 0.000), duration (St diff mean = 0.803, P = 0.000), and severity (St diff mean = 0.637, P = 0.000) of OM in pediatric cancer patients significantly. However, the laser did not show significant efficacy in decreasing the incidence rate of OM (OR = 2.870, P = 0.364).

CONCLUSION

This review provided a comprehensive examination of available options for children who have OM. The results support the possibility of a positive effect of palifermin on reducing OM in children receiving cancer therapy.

Intestinal Microbiota Influence Immune Tolerance Post Allogeneic Hematopoietic Cell Transplantation and Intestinal GVHD

Under normal conditions our intestines are inhabited by trillions of diverse microorganisms composing the intestinal microbiota, which are mostly non-pathogenic anaerobic commensal bacteria vital for the maintenance of immune homeostasis. The composition and diversity of the intestinal microbiota can be disturbed by various factors including diet, antibiotics, and exposure to intestinal pathogens. Alterations of the intestinal microbiota contributes to many diseases including graft-vs.-host disease (GVHD), a life threatening complication that occurs after allogeneic hematopoietic cell transplantation (allo-HCT) caused by an allogeneic reaction of donor T cells against recipient target tissues. Intestinal GVHD is most difficult to treat and connected to a high mortality. Due to recent advances in high-throughput sequencing technology, composition of the microbiome during allo-HCT has been characterized, and some common patterns have been identified. Metabolites produced by intestinal bacteria were shown to promote intestinal tissue homeostasis and immune tolerance post-allo-HCT. In this review, we discuss the role of the intestinal microbiota and metabolites in the context of acute GVHD. Moreover, novel therapeutic approaches that aim at protecting or regenerating intestinal cell populations will be highlighted.

Biology-driven developments in the therapy of acute graft-versus-host disease

Allogeneic hematopoietic cell transplantation is a potentially curative treatment of different hematological malignancies. A major life-threatening complication is acute graft-versus-host disease (GVHD), in particular when the disease becomes steroid refractory. Based on the detection of pathogenic cytokines, chemokines, and T-cell subsets in individuals developing GVHD or experimental GVHD models, different therapeutic strategies have been developed. A potential cause why targeting individual receptors can lack efficacy could be that multiple cytokines, danger signals, and chemokine that have redundant functions are released during GVHD. To overcome this redundancy, novel strategies that do not target individual surface molecules like chemokine receptors, integrins, and cytokine receptors, but instead inhibit signaling pathways downstream of these molecules, have been tested in preclinical GVHD models and are currently being tested in clinical GVHD trials. Another important development is tissue regenerative approaches that promote healing of GVHD-related tissue damage as well as strategies that rely on microbiota modifications. These approaches are promising because they act very differently from conventional immunosuppression, instead aiming at reinstalling tissue homeostasis and microbiome diversity. This review discusses major novel developments in GVHD therapy that are based on a better understanding of GVHD biology, the repurposing of novel kinase inhibitors, microbiome modification strategies, and tissue-regenerative approaches.

Pretransplant Serum Citrulline Predicts Acute Graft-versus-Host Disease

Post-transplant biomarkers of acute graft-versus-host disease (aGVHD) and nonrelapse mortality (NRM) after allogeneic hematopoietic cell transplantation (allo-HCT) have been extensively studied. However, pretransplant biomarkers may provide a greater window of opportunity to intervene. We measured serum biomarkers of various aspects of gut barrier physiology before HCT (median, day -7) and 7 and 28 days post-HCT in 95 consecutive allo-HCT recipients enrolled in an open-label biorepository protocol. Biomarkers included citrulline for total functional enterocyte mass, Reg3a for antibacterial activity of the gut, and intestinal fatty acid binding protein (I-FABP) for enterocyte turnover. Compared to 16 healthy control subjects, we demonstrated that patients came to transplant with abnormal levels of all 3 biomarkers (P < .05), reflecting residual damage from prior chemotherapy. All 3 biomarkers initially declined from pre-HCT to day +7 (more pronounced after myeloablative than reduced-intensive conditioning) followed by a recovery phase and return toward pre-HCT values by day +28. A lower pre-HCT citrulline was independently associated with a higher risk of aGVHD grades II to IV (hazard ratio, 1.32; 95% confidence interval, 1.03 to 1.69; P = .02), and this association was not specific to gut GVHD. The strongest correlate of NRM was a higher level of Reg3a at day +7 (P < .001). I-FABP did not predict transplant outcomes. In conclusion, pre-HCT serum citrulline levels identify patients at high risk for developing aGVHD. Our results suggest that pre-HCT interventions to augment the gut barrier may decrease the risk of aGVHD.

Efficacy of palifermin on oral mucositis and acute GVHD after hematopoietic stem cell transplantation (HSCT) in hematology malignancy patients: a meta-analysis of trials

Aim of the study

Herein, this meta-analysis study evaluated the efficacy of palifermin after HSCT on the incidence and severity of OM or aGVHD in hematologic malignancy patients in randomized clinical trials (RCTs).

Materials and methods

To compare the efficacy of palifermin on adverse events, OM and aGVHD compared with placebo, we searched databases of PubMed/Medline, Web of Science and Cochrane Library for RCTs based on a number of criteria.

Results

There was no difference observed in the incidence of OM and aGVHD between two groups. The subgroup analysis didn’t show significant differences in two groups for aGVHD grade 2–4 (odds ratio [OR] = 1.54, 95% confidence interval (CI): 0.70–3.39, p = 0.28), aGVHD grade 3–4 (OR = 0.97, 95% CI: 0.48–1.94, p = 0.92), OM grade 2–4 (OR = 0.76, 95% CI: 0.42–1.38, p = 0.37) and OM grade 3–4 (OR = 0.54, 95% CI: 0.25–1.15, p = 0.11], but erythema as an adverse effect in palifermin group was higher than placebo group (OR = 1.86, 95% CI: 1.10–3.15, p = 0.02].

Conclusions

This meta-analysis of six clinical trials found no statistically significant difference in OM and aGVHD grades in patients receiving 60 μg/kg/day dose of palifermin compared with those receiving a placebo. However, oral mucosal erythema was more prevalent among patients receiving palifermin than patients receiving a placebo.

Interventions for preventing oral mucositis in patients with cancer receiving treatment: cytokines and growth factors

BACKGROUND

Oral mucositis is a side effect of chemotherapy, head and neck radiotherapy, and targeted therapy, affecting over 75% of high-risk patients. Ulceration can lead to severe pain and difficulty with eating and drinking, which may necessitate opioid analgesics, hospitalisation and supplemental nutrition. These complications may disrupt cancer therapy, which may reduce survival. There is also a risk of death from sepsis if pathogens enter the ulcers of immunocompromised patients. Ulcerative oral mucositis can be costly to healthcare systems, yet there are few preventive interventions proven to be beneficial. Cytokines and growth factors may help the regeneration of cells lining of the mouth, thus preventing or reducing oral mucositis and its negative effects.

OBJECTIVES

To assess the effects of cytokines and growth factors for preventing oral mucositis in patients with cancer who are receiving treatment.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (searched 10 May 2017); the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 4) in the Cochrane Library (searched 10 May 2017); MEDLINE Ovid (1946 to 10 May 2017); Embase Ovid (7 December 2015 to 10 May 2017); CINAHL EBSCO (Cumulative Index to Nursing and Allied Health Literature; 1937 to 10 May 2017); and CANCERLIT PubMed (1950 to 10 May 2017). The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials.

SELECTION CRITERIA

We included parallel-design randomised controlled trials (RCTs) assessing the effects of cytokines and growth factors in patients with cancer receiving treatment.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the results of electronic searches, extracted data and assessed risk of bias. For dichotomous outcomes, we reported risk ratios (RR) and 95% confidence intervals (CI). For continuous outcomes, we reported mean differences (MD) and 95% CIs. We pooled similar studies in random-effects meta-analyses. We reported adverse effects in a narrative format.

MAIN RESULTS

We included 35 RCTs analysing 3102 participants. Thirteen studies were at low risk of bias, 12 studies were at unclear risk of bias, and 10 studies were at high risk of bias.Our main findings were regarding keratinocyte growth factor (KGF) and are summarised as follows.There might be a reduction in the risk of moderate to severe oral mucositis in adults receiving bone marrow/stem cell transplantation after conditioning therapy for haematological cancers (RR 0.89, 95% CI 0.80 to 0.99; 6 studies; 852 participants; low-quality evidence). We would need to treat 11 adults with KGF in order to prevent one additional adult from developing this outcome (95% CI 6 to 112). There might be a reduction in the risk of severe oral mucositis in this population, but there is also some possibility of an increase in risk (RR 0.85, 95% CI 0.65 to 1.11; 6 studies; 852 participants; low-quality evidence). We would need to treat 10 adults with KGF in order to prevent one additional adult from developing this outcome (95% CI 5 to prevent the outcome to 14 to cause the outcome).There is probably a reduction in the risk of moderate to severe oral mucositis in adults receiving radiotherapy to the head and neck with cisplatin or fluorouracil (RR 0.91, 95% CI 0.83 to 1.00; 3 studies; 471 participants; moderate-quality evidence). We would need to treat 12 adults with KGF in order to prevent one additional adult from developing this outcome (95% CI 7 to infinity). It is very likely that there is a reduction in the risk of severe oral mucositis in this population (RR 0.79, 95% CI 0.69 to 0.90; 3 studies; 471 participants; high-quality evidence). We would need to treat 7 adults with KGF in order to prevent one additional adult from developing this outcome (95% CI 5 to 15).It is likely that there is a reduction in the risk of moderate to severe oral mucositis in adults receiving chemotherapy alone for mixed solid and haematological cancers (RR 0.56, 95% CI 0.45 to 0.70; 4 studies; 344 participants; moderate-quality evidence). We would need to treat 4 adults with KGF in order to prevent one additional adult from developing this outcome (95% CI 3 to 6). There might be a reduction in the risk of severe oral mucositis in this population (RR 0.30, 95% CI 0.14 to 0.65; 3 studies; 263 participants; low -quality evidence). We would need to treat 10 adults with KGF in order to prevent one additional adult from developing this outcome (95% CI 8 to 19).Due to the low volume of evidence, single-study comparisons and insufficient sample sizes, we found no compelling evidence of a benefit for any other cytokines or growth factors and there was no evidence on children. There did not appear to be any serious adverse effects of any of the interventions assessed in this review.

AUTHORS' CONCLUSIONS

We are confident that KGF is beneficial in the prevention of oral mucositis in adults who are receiving: a) radiotherapy to the head and neck with cisplatin or fluorouracil; or b) chemotherapy alone for mixed solid and haematological cancers. We are less confident about a benefit for KGF in adults receiving bone marrow/stem cell transplant after conditioning therapy for haematological cancers because of multiple factors involved in that population, such as whether or not they received total body irradiation (TBI) and whether the transplant was autologous (the patients' own cells) or allogeneic (cells from a donor). KGF appears to be a relatively safe intervention.Due to limited research, we are not confident that there are any beneficial effects of other cytokines and growth factors. There is currently insufficient evidence to draw any conclusions about the use of cytokines and growth factors in children.

The gastrointestinal tract: properties and role in allogeneic hematopoietic stem cell transplantation

INTRODUCTION

The GI-tract is a major target for both the intensive chemo and/or radiotherapy conditioning as well as for GVHD and therefore is closely associated with transplant outcome. Apart from being a target, the GI-tract is also a mediator and therefore is also a key player of the pathogenetic process following allogeneic transplantation. Areas covered: The intestinal homeostasis is regulated through complicated interactions between the key players of this process which are the intestinal epithelium, the intestinal immune system, and the intestinal microbiota. A brief description of these elements, based on published english-language articles in PubMed, as well as their role during the process of allo-HSCT is discussed in this review. Expert commentary: Data on GI-tract properties suggest a central role for the intestine in regulation of immunity, both in healthy - steady state conditions and in pathological states such as during allo-HSCT. Given the fact that in the allogeneic transplant setting severe complications such as infections and GVHD are limiting this treatment modality, understanding the mechanisms that mediate intestinal homeostasis could lead to new preventive methods and improved outcomes.

Pathogenesis of acute graft-versus-host disease: from intestinal microbiota alterations to donor T cell activation

Acute graft-versus-host disease (aGVHD) is a major life-threatening complication of allogeneic haematopoietic cell transplantation (allo-HCT). Here we discuss the aGVHD pathophysiology initiated by multiple signals that cause alloreactive T-cell activation. The outcome of such donor T-cell activation is influenced by T-cell receptor-signal strength, anatomical location, co-stimulatory/co-inhibitory signals and differentiation stage (naive, effector/memory) of T-cells. Additionally, cross-priming of T cells to antigens expressed by pathogens can contribute to aGVHD-mediated tissue injury. In addition to the properties of donor T-cell activation, highly specialized tissue resident cell types, such as innate lymphoid cells, antigen-presenting cells, immune regulatory cells and various intestinal cell populations are critically involved in aGVHD pathogenesis. The role of the thymus and secondary lymphoid tissue injury, non-haematopoietic cells, intestinal microflora, cytokines, chemokines, microRNAs, metabolites and kinases in aGVHD pathophysiology will be highlighted. Acute GVHD pathogenic mechanisms will be connected to novel therapeutic approaches under development for, and tested in, the clinic.

The Impact of Palifermin Use on Hematopoietic Cell Transplant Outcomes in Children

Clinical trials evaluating palifermin have enrolled few pediatric patients, precluding safety analyses in large groups of children. We compared hematopoietic cell transplantation (HCT) outcomes among pediatric patients who did or did not receive palifermin as a preventive treatment for oral mucositis. Pediatric patients and controls, matched for HCT and donor type, disease, disease status, and age, were selected from the Center for International Blood and Marrow Transplant Research database and a 1:3 matched cohort analysis was performed. Stratified Cox proportional hazards models were built and propensity score adjustments were used to compare overall and disease-free survival outcomes between palifermin-treated and untreated patients. Three controls were identified for 90% of palifermin recipients. The remaining cases were matched with 2 (8%) controls or 1 (2%) control, for a total of 210 palifermin-treated patients matched with 606 controls. Median follow-up was 31 months in cases and 36 months in controls. Fifty-seven percent of patients underwent allogeneic HCT, mostly for acute leukemia, and 43% underwent autologous HCT, mostly for solid tumors. In univariate analyses, 2-year survival and disease-free survival rates after allogeneic HCT (58% versus 66%, P = .109; 49% versus 60%, P = .06) and after autologous HCT (73% versus 77%, P = .474; 60% versus 64%, P = .637) were similar between palifermin-treated patients and matched controls. In multivariate analysis, palifermin treatment did not significantly increase the risk of mortality (relative risk [RR], 1.20; 95% confidence interval [CI], .87 to 1.66) or of relapse (RR, 1.12; 95% CI, .78 to 1.62) compared with matched controls. No significant differences in rates of acute or chronic graft-versus-host disease (GVHD) were observed between palifermin-treated patients and matched controls. Among pediatric patients undergoing HCT, overall survival, disease-free survival, neutrophil recovery, and GVHD rates were similar between palifermin-treated patients and matched controls.

CD34+ selection and the severity of oropharyngeal mucositis in total body irradiation-based allogeneic stem cell transplantation

OBJECTIVE

The purpose of the present study was to evaluate the impact of ex vivo T cell depleted (TCD) by CD34+ selection on the incidence and severity of oropharyngeal mucositis (OM) after myeloablative allogeneic stem cell transplant (allo-SCT) with total body irradiation (TBI) conditioning. This approach has the advantage of avoiding methotrexate for graft versus host disease (GVHD) prophylaxis.

PATIENTS AND METHODS

We analyzed the incidence and severity of OM in a cohort of 105 consecutive patients who underwent CD34+ selected (peripheral blood stem cells (PBSCs) from human leukocyte antigen (HLA)-identical siblings) allo-SCT with total body irradiation (TBI) conditioning. OM was graded by the World Health organization (WHO) and the Bearman regimen-related toxicity (RRT) scales.

RESULTS

The incidence of WHO grade 3-4 OM was 34.3 %. There were no cases of grade 3-4 OM by the RRT scale. Significant correlation was found between the severity of OM and the use of intravenous (IV) narcotic medications (r (2) = 0.15, p = 0.004), total parenteral nutrition (TPN; r (2) = 0.68, p < 0.001), and hospital length of stay (LOS) (r (2) = 0.12, p = 0.01).

DISCUSSION

TBI-induced OM can inflict significant morbidity in the early transplant period, and the incidence of WHO grade 3-4 OM can exceed 50 % when methotrexate is used for GVHD prophylaxis. In the CD34+ selected setting, methotrexate is avoided and the incidence of WHO grade 3-4 OM, use of TPN, and need for narcotic analgesia appear to be lower than historic evidence from standard T-replete allogeneic transplantation.

CONCLUSION

We conclude that toxicity from OM is tolerable in CD34+ selected allo-SCT and should be prospectively measured in randomized trials comparing CD34+ selection versus T-replete transplantation.

Cytokines in Graft-versus-Host Disease

Graft-versus-host disease (GVHD) is a complication of allogeneic bone marrow transplantation whereby transplanted naive and marrow-derived T cells damage recipient tissue through similar mechanisms to those that allow destruction of malignant cells, the therapeutic intent of bone marrow transplantation. The manifestations and severity of GVHD are highly variable and are influenced by the proportions of naive cells maturing along regulatory T cell, Th1, Th2, or Th17 phenotypes. This maturation is largely influenced by local cytokines, which, in turn, activate transcription factors and drive development toward a dominant phenotype. In addition, proinflammatory cytokines exert direct effects on GVHD target tissues. Our knowledge of the role that cytokines play in orchestrating GVHD is expanding rapidly and parallels other infective and inflammatory conditions in which a predominant T cell signature is causative of pathology. Because a broad spectrum of cytokine therapies is now routinely used in clinical practice, they are increasingly relevant to transplant medicine.

Intestinal barrier loss as a critical pathogenic link between inflammatory bowel disease and graft-versus-host disease

Compromised intestinal barrier function is a prominent feature of inflammatory bowel disease (IBD). However, links between intestinal barrier loss and disease extend much further, including documented associations with celiac disease, type I diabetes, rheumatoid arthritis, and multiple sclerosis. Intestinal barrier loss has also been proposed to have a critical role in the pathogenesis of graft-versus-host disease (GVHD), a serious, potentially fatal consequence of hematopoietic stem cell transplantation. Experimental evidence has begun to support this view, as barrier loss and its role in initiating and establishing a pathogenic inflammatory cycle in GVHD is emerging. Here we discuss similarities between IBD and GVHD, mechanisms of intestinal barrier loss in these diseases, and the crosstalk between barrier loss and the immune system, with a special focus on natural killer (NK) cells. Unanswered questions and future research directions on the topic are discussed along with implications for treatment.

Guideline for the prevention of oral and oropharyngeal mucositis in children receiving treatment for cancer or undergoing haematopoietic stem cell transplantation

PURPOSE

To develop an evidence-based clinical practice guideline for the prevention of oral mucositis in children (0-18 years) receiving treatment for cancer or undergoing haematopoietic stem cell transplantation (HSCT).

METHODS

The Mucositis Prevention Guideline Development Group was interdisciplinary and included internationally recognised experts in paediatric mucositis. For the evidence review, we included randomised controlled trials (RCTs) conducted in either children or adults evaluating the following interventions selected according to prespecified criteria: cryotherapy, low level light therapy (LLLT) and keratinocyte growth factor (KGF). We also examined RCTs of any intervention conducted in children. For all systematic reviews, we synthesised the occurrence of severe oral mucositis. The Grades of Recommendation, Assessment, Development and Evaluation approach was used to describe quality of evidence and strength of recommendations.

RESULTS

We suggest cryotherapy or LLLT may be offered to cooperative children receiving chemotherapy or HSCT conditioning with regimens associated with a high rate of mucositis. We also suggest KGF may be offered to children receiving HSCT conditioning with regimens associated with a high rate of severe mucositis. However, KGF use merits caution as there is a lack of efficacy and toxicity data in children, and a lack of long-term follow-up data in paediatric cancers. No other interventions were recommended for oral mucositis prevention in children.

CONCLUSIONS

All three specific interventions evaluated in this clinical practice guideline were associated with a weak recommendation for use. There may be important organisational and cost barriers to the adoption of LLLT and KGF. Considerations for implementation and key research gaps are highlighted.

The role of pattern-recognition receptors in graft-versus-host disease and graft-versus-leukemia after allogeneic stem cell transplantation

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the only treatment with curative potential for certain aggressive hematopoietic malignancies. Its success is limited by acute graft-versus-host disease (GVHD), a life-threatening complication that occurs when allo-reactive donor T cells attack recipient organs. There is growing evidence that microbes and innate pattern-recognition receptors (PRRs) such as toll-like receptors (TLR) and nod-like receptors (NLR) are critically involved in the pathogenesis of acute GVHD. Currently, a widely accepted model postulates that intensive chemotherapy and/or total-body irradiation during pre-transplant conditioning results in tissue damage and a loss of epithelial barrier function. Subsequent translocation of bacterial components as well as release of endogenous danger molecules stimulate PRRs of host antigen-presenting cells to trigger the production of pro-inflammatory cytokines (cytokine storm) that modulate T cell allo-reactivity against host tissues, but eventually also the beneficial graft-versus-leukemia (GVL) effect. Given the limitations of existing immunosuppressive therapies, a better understanding of the molecular mechanisms that govern GVHD versus GVL is urgently needed. This may ultimately allow to design modulators, which protect from GvHD but preserve donor T-cell attack on hematologic malignancies. Here, we will briefly summarize current knowledge about the role of innate immunity in the pathogenesis of GVHD and GVL following allo-HSCT.

Impact of palifermin on incidence of oral mucositis and healthcare utilization in children undergoing autologous hematopoietic stem cell transplantation for malignant diseases

Palifermin has been demonstrated to decrease the incidence of severe oral mucositis in adults following TBI containing conditioning regimens prior to AHSCT. The impact of palifermin on the incidence of oral mucositis in children undergoing AHSCT has never been studied. We compared the effect of palifermin on the incidence of oral mucositis and supportive care in 58 children undergoing myeloablative AHSCT; 25 children received palifermin and 33 children did not receive palifermin (control arm). Oral mucositis was graded as per WHO criteria. The demographic characteristics were comparable between the two arms. Results comparing the palifermin vs. control arm showed that the incidence of grade III-IV oral mucositis was 20% vs. 42.4% (p = 0.072). The number of days patients received patient-controlled analgesia and total parenteral nutrition in the palifermin vs. control arm were 8.80 ± 8.39 vs. 8.30 ± 8.54 (p = 0.826) and 13.52 ± 11.32 vs. 11.55 ± 9.63 (p = 0.484), respectively. The average length of hospitalization in the palifermin vs. control arm was 31.44 ± 7.42 vs. 28.61 ± 10.38 (p = 0.252), respectively. In this study, we were unable to demonstrate a statistical difference in the incidence of oral mucositis and other supportive care needs or a decrease in hospital stay between the two arms.

Improving engraftment and immune reconstitution in umbilical cord blood transplantation

Umbilical cord blood (UCB) is an important source of hematopoietic stem cells (HSC) for allogeneic transplantation when HLA-matched sibling and unrelated donors (MUD) are unavailable. Although the overall survival results for UCB transplantation are comparable to the results with MUD, UCB transplants are associated with slow engraftment, delayed immune reconstitution, and increased opportunistic infections. While this may be a consequence of the lower cell dose in UCB grafts, it also reflects the relative immaturity of cord blood. Furthermore, limited cell numbers and the non-availability of donor lymphocyte infusions currently prevent the use of post-transplant cellular immunotherapy to boost donor-derived immunity to treat infections, mixed chimerism, and disease relapse. To further develop UCB transplantation, many strategies to enhance engraftment and immune reconstitution are currently under investigation. This review summarizes our current understanding of engraftment and immune recovery following UCB transplantation and why this differs from allogeneic transplants using other sources of HSC. It also provides a comprehensive overview of promising techniques being used to improve myeloid and lymphoid recovery, including expansion, homing, and delivery of UCB HSC; combined use of UCB with third-party donors; isolation and expansion of natural killer cells, pathogen-specific T cells, and regulatory T cells; methods to protect and/or improve thymopoiesis. As many of these strategies are now in clinical trials, it is anticipated that UCB transplantation will continue to advance, further expanding our understanding of UCB biology and HSC transplantation.

Prevention and treatment of oral mucositis in patients receiving chemotherapy

Oral mucositis is one of the most common side effects of cancer treatment (chemotherapy and/or radiotherapy). It is an inflammatory process that affects the mucosa of the oral cavity, giving rise to erythematous areas in combination with ulcers that can reach a large size. The true importance of oral mucositis is the complications it causes - fundamentally intense pain associated to the oral ulcers, and the risk of overinfection. This in turn may require reduction or even suspension of the antineoplastic treatment, with the risk of seriously worsening the patient prognosis. This points to the importance of establishing therapeutic tools of use in the prevention and/or treatment of mucositis. The present study offers a literature review of all the articles published over the last 10 years referred to the prevention and/or treatment of oral mucositis associated to chemotherapy. Key words:Oral mucositis, management, prevention, treatment, chemotherapy.

Clinical effectiveness of palifermin in prevention and treatment of oral mucositis in children with acute lymphoblastic leukaemia: a case-control study

The aim of this study was to evaluate the efficacy of palifermin, an N-terminal truncated version of endogenous keratinocyte growth factor, in the control of oral mucositis during antiblastic therapy. Twenty patients undergoing allogeneic stem-cell transplantation for acute lymphoblastic leukaemia were treated with palifermin, and compared to a control group with the same number of subjects and similar inclusion criteria. Statistical analysis were performed to compare the outcomes in the treatment vs. control groups. In the treatment group, we found a statistically significant reduction in the duration of parenteral nutrition (P=0.002), duration of mucositis (P=0.003) and the average grade of mucositis (P=0.03). The statistical analysis showed that the drug was able to decrease the severity of mucositis. These data, although preliminary, suggest that palifermin could be a valid therapeutic adjuvant to improve the quality of life of patients suffering from leukaemia.

Clinical applications of palifermin: amelioration of oral mucositis and other potential indications

Mucositis is one of the most significant toxicities in cancer patients undergoing cytotoxic treatment. It can have a negative impact on both quality of life and health economics. Severe oral mucositis can contribute to hospitalization, need for narcotic analgesics, total parentral nutrition, suboptimal delivery of anti-neoplastic treatment, and morbidity and mortality. Palifermin, a recombinant derivative of human keratinocyte growth factor, is the first active agent approved by the FDA for the prevention of severe oral mucositis in patients undergoing haematopoietic stem cell transplantation (HSCT). Several studies have also shown significant reduction in the incidence, severity and/or duration of oral mucositis in other high-risk settings such as concurrent chemoradiotherapy (CT/RT) for patients with head and neck cancer, and use of mucotoxic chemotherapeutic agents such as doxorubicin in sarcoma and fluorouracil for the treatment of colorectal cancer. The reduction in mucositis has translated into amelioration of symptoms and improvement in daily functioning as measured by patient-reported outcome in multiple studies. The clinical response to palifermin appears to be related in part to epithelial proliferation and mucosal thickening. Palifermin also has other potential clinical applications including the acceleration of immune reconstitution and inhibition of graft-versus-host disease in patients undergoing HSCT, and mitigation of dysphagia in lung cancer patients treated with concurrent CT/RT. Palifermin is generally well tolerated with mild-to-moderate skin and oral adverse events. Future studies may expand the use of palifermin into other areas that would benefit from its cytoprotective and regenerative effects.

Increasing and worsening late effects in childhood cancer survivors during follow-up

Recent advances in childhood cancer treatment have increased survival rates to 80%. Two out of three survivors experience late effects (LEs). From a group of 241 survivors previously described, 193 were followed at the long-term follow-up clinic (LTFC) of Severance Hospital in Korea; the presence of LEs was confirmed by oncologists. We reported the change in LEs during 3 yr of follow-up. The median follow-up from diagnosis was 10.4 yr (5.1-26.2 yr). Among 193 survivors, the percentage of patients with at least one LE increased from 63.2% at the initial visit to 75.1% at the most recent visit (P = 0.011). The proportion of patients having multiple LEs and grade 2 or higher LEs increased from the initial visit (P = 0.001 respectively). Forty-eight non-responders to the LTFC were older and had less frequent and severe LEs than responders at initial visit (all P < 0.05). In multivariate analysis, younger age at diagnosis, older age at initial visit, a diagnosis of a brain tumor or lymphoma, and use of radiotherapy were significant risk factors for LEs (all P < 0.05). Adverse changes in LEs were seen among the survivors, regardless of most clinical risk factors. They need to receive comprehensive, long-term follow up.

Prevention and treatment of oral mucositis in children with cancer

Oral mucositis affects more than three-fourths of patients undergoing chemotherapy and represents a significant burden to patients and caregivers. Lesions develop as a result of chemotherapeutic agents attacking the rapidly dividing cells of the gastrointestinal tract. Severity can range from mild, painless tissue changes to bleeding ulcerations that prevent oral intake and require narcotic pain relievers. Oral mucositis also leads to an increased risk of infection and can often delay further chemotherapy treatment. A number of assessment scales have been developed to better qualify the symptoms associated with this condition. Few pharmacologic agents have been approved to either prevent the development or alleviate the symptoms of oral mucositis. Current options include the use of antimicrobial mouthwashes, amino acid rinses, and topical healing agents. Palifermin, a keratinocyte growth factor, may be a future option after its use in children is explored. With achievements in other areas of supportive care in patients undergoing chemotherapy, oral mucositis should represent the forefront of new research. This review will provide a comprehensive examination of available options for children who have oral mucositis.