Heterotopic ossification related to the use of recombinant human BMP-2 in osteonecrosis of femoral head.

Despite the wide use of recombinant human bone morphogenetic protein-2 (rhBMP-2) in bone defect, its application in treating osteonecrosis of femoral head (ONFH) is yet to be elucidated. The heterotopic ossification (HO) after rhBMP-2 usage in some orthopedic surgeries has been reported previously; however, only a few studies describe this complication in the treatment of ONFH.The present study investigated whether the rhBMP-2 application would increase the risk of HO formation in selected ONFH patients with nonvascularized bone grafting surgery and enhance the surgical results of nonvascularized bone grafting as compared to patients who did not receive intraoperative rhBMP-2.A retrospective analysis was performed on 94 patients (141 hips) who, with Association Research Circulation Osseous (ARCO) stages IIb, IIc, and IIIa ONFH, underwent nonvascularized bone grafting surgery. The first 46 patients (66 hips) received intraoperative rhBMP-2. The postoperative radiographic results (X-ray and CT scan) and Harris hip score (HHS) were reviewed in each patient to record the incidence of HO formation and evaluate the clinical efficacy of rhBMP-2, respectively.HO formation frequently occurred in patients receiving intraoperative rhBMP-2 (8/66 hips) than those not receiving the protein (1/75 hips) (P = .02). HHS improved from preoperatively at the final follow-up (P < .01) in the BMP-positive group, with a survival rate of 83.3%. In the BMP-negative group, the HHS improved from preoperatively at the end of the follow-up (P < .01), and the survival rate was 72.0%.rhBMP-2 has osteoinductive property and might serve as an adjuvant therapy in the surgical treatment of ONFH. However, the incidence of HO formation might increase when used in high doses.

Adipose-derived stem cells combined with neuregulin-1 delivery systems for heart tissue engineering.

Myocardial infarction (MI) is the leading cause of death worldwide, and extensive research has therefore been performed to find a cure. Neuregulin-1 (NRG) is a growth factor involved in cardiac repair after MI. We previously described how biocompatible and biodegradable microparticles, which are able to release NRG in a sustained manner, represent a valuable approach to avoid problems related to the short half-life after systemic administration of proteins. The effectiveness of this strategy could be improved by combining NRG with several cytokines involved in cardiac regeneration. The present study investigates the potential feasibility of using NRG-releasing particle scaffold combined with adipose-derived stem cells (ADSC) as a multiple growth factor delivery-based tissue engineering strategy for implantation in the infarcted myocardium. NRG-releasing particle scaffolds with a suitable size for intramyocardial implantation were prepared by TROMS. Next, ADSC were adhered to particle scaffolds and their potential for heart administration was assessed in a MI rat model. NRG was successfully encapsulated reaching encapsulation efficiencies of 92.58 ± 3.84%. NRG maintained its biological activity after the microencapsulation process. ADSCs adhered efficiently to particle scaffolds within a few hours. The ADSC-cytokine delivery system developed proved to be compatible with intramyocardial administration in terms of injectability through a 23-gauge needle and tissue response. Interestingly, ADSC-scaffolds were present in the peri-infarted tissue 2 weeks after implantation. This proof of concept study provides important evidence required for future effectiveness studies and for the translation of this approach.

Investigating new therapeutic strategies targeting hyperinsulinemia's mitogenic effects in a female mouse breast cancer model.

Epidemiological and experimental studies have identified hyperinsulinemia as an important risk factor for breast cancer induction and for the poor prognosis in breast cancer patients with obesity and type 2 diabetes. Recently it was demonstrated that both the insulin receptor (IR) and the IGF-IR mediate hyperinsulinemia's mitogenic effect in several breast cancer models. Although IGF-IR has been intensively investigated, and anti-IGF-IR therapies are now in advanced clinical trials, the role of the IR in mediating hyperinsulinemia's mitogenic effect remains to be clarified. Here we aimed to explore the potential of IR inhibition compared to dual IR/IGF-IR blockade on breast tumor growth. To initiate breast tumors, we inoculated the mammary carcinoma Mvt-1 cell line into the inguinal mammary fat pad of the hyperinsulinemic MKR female mice, and to study the role of IR, we treated the mice bearing tumors with the recently reported high-affinity IR antagonist-S961, in addition to the well-documented IGF-IR inhibitor picropodophyllin (PPP). Although reducing IR activation, with resultant severe hyperglycemia and hyperinsulinemia, S961-treated mice had significantly larger tumors compared to the vehicle-treated group. This effect maybe secondary to the severe hyperinsulinemia mediated via the IGF-1 receptor. In contrast, PPP by partially inhibiting both IR and IGF-IR activity reduced tumor growth rate with only mild metabolic consequences. We conclude that targeting (even partially) both IR and IGF-IRs impairs hyperinsulinemia's effects in breast tumor development while simultaneously sparing the metabolic abnormalities observed when targeting IR alone with virtual complete inhibition.

The role of growth hormone and insulin-like growth factor-1 in Crohn's disease: implications for therapeutic use of human growth hormone in pediatric patients.

PURPOSE OF REVIEW: This review evaluates the role of the growth hormone (GH) and insulin-like growth factor (IGF) in influencing linear growth in pediatric Crohn's disease. It also examines the current evidence concerning the use of recombinant human growth hormone (rhGH) as a potential therapy in achieving optimal growth and inducing mucosal healing for pediatric Crohn's disease. RECENT FINDINGS: Current treatment strategies for Crohn's disease including antitumor necrosis factor-α (TNF-α) therapy have been demonstrated to improve growth velocity, but linear growth deficits persist despite optimization of therapy. By complex mechanisms, including the reduction of levels of IGF-1 and induction of systemic and hepatic GH resistance, cytokines such as TNF-α and interleukin-6 (IL-6), commonly elevated in active Crohn's disease, are important as mediators of linear growth delay. Recent evidence suggests that rhGH therapy is effective in improving short-term linear growth for a selected group of patients but of limited benefit as a therapy for improving mucosal disease and reducing clinical disease activity. SUMMARY: Crohn's disease interacts with the GH-IGF-1 axis in important ways. Recent studies evaluating rhGH use in pediatric Crohn's disease have demonstrated some efficacy in reversing persistent linear growth delay but limited benefits in terms of improving mucosal disease and clinical disease activity. Larger studies of adequate power are needed to confirm a true benefit in terms of growth, to examine a potential benefit with regard to modification of disease activity, and to evaluate long-term risks.

Mecasermin: new drug. Insufficient improvement in statural growth.

(1) Human insulin-like growth factor type 1 (IGF-1) is the main effector of growth hormone action. Primary IGF-1 deficiency is a rare disease, mainly resulting in very short stature; (2) Mecasermin is a recombinant IGF-1 marketed for this indication as a twice daily subcutaneous injection; (3) Clinical evaluation is mainly based on a non-comparative follow-up study of 76 children with an average age of 7 years, some of whom were treated for 8 years. The mean height at treatment initiation was 6.7 standard deviations below normal. Eight years later, it was 5.2 standard deviations below normal, i.e. their growth failure remained very severe; (4) The main short-term adverse effects of mecasermin are hypoglycaemia, headache and intracranial hypertension. Nearly one in 5 children developed tonsillar hypertrophy, resulting in otitis and hypoacusis; (5) Animal studies showed hypertrophy of other organs (kidneys, spleen and heart) as well as carcinogenic effects. The risk in humans is unknown; (6) The mecasermin packaging is not well-adapted (a multidose vial designed to be punctured several times), and is a potential source of contamination and errors. Prefilled pens or syringes would be easier to use; (7) In practice, the limited clinical benefits of mecasermin do not justify exposure to its potential risks.

Growth-promotant implants: managing the tools.

Great contemplation, conversation, and controversy have surrounded the use of growth-promotant implants since their inception in the 1950s. Since the very beginning, the purpose of growth promotants has been to enhance production efficiency, reduce the cost of production, and improve profitability. Changes in our understanding of the physiologic mechanisms involved in growth promotion have not altered this fundamental purpose. With enhanced knowledge of the impact of various compounds and doses on different classes of animals, and with the introduction of numerous products providing those compounds and doses, planning implant programs has become difficult. However, the net return from a well-designed implant program may mean the difference between profit and loss on a given set of cattle.

Interrelación entre hormonas tiroideas y crecimiento: importancia clínica / Relationship between thyroid hormones and the growth: clinical importance

En la práctica clínica correspondiente a la endocrinología pediátrica, los trastornos del crecimiento son motivo frecuente de consulta y es la hipofunción tiroidea su causa más común. Por esta razón nos propusimos revisar aspectos teóricos relacionados con la función tiroidea, que pudieran explicar el mecanismo mediante el cual las hormonas tiroideas intervienen en el desarrollo del cartílago de crecimiento y del sistema nervioso central. Se revisa brevemente el mecanismo de regulación de las hormonas tiroideas y del efecto de los factores de crecimiento, tanto en la vida intrauterina como en la etapa posnatal. Se expone una hipótesis para explicar cómo ocurre la interrelación entre hormonas tiroideas (factores de crecimiento). Al final se hace referencia al impacto clínico del déficit de hormonas tiroideas durante la infancia(AU)

[Growth factors and wound healing: review and prospect in recent ten years].

OBJECTIVE: To review the current condition of growth factors and their application to clinical treatment of acute and chronic wounds. METHODS: Data from the literature and Medline were analyzed according to their different uses in acute and chronic wounds. Their potential side-effects were studied. RESULTS: All data showed that wound healing time in acute and chronic wounds was accelerated and wound healing quality was improved after treatment with growth factors. No side-effect was observed. CONCLUSION: The efficacy and safety of growth factors in improving wound healing were confirmed. However, some reconsideration about potential problems of growth factors must be made to apply them clinically in the future.

Effects of growth factors and receptor blockade on gastrointestinal cancer.

The advent of recombinant peptide technology offers the potential to use one or several peptides to treat a variety of gastrointestinal conditions. However, although cell culture and animal models have shown proof of concept, we are still at a relatively early stage in translating their use to standard clinical practice. Similarly, peptide and non-peptide antagonists of growth factor receptors show great potential as novel antichemotherapy agents. However, their actual place in clinical practice has yet to be established.

Immunotherapy for invasive fungal infections: from bench to bedside.

Immunotherapy for invasive fungal infections has been an area of significant research and clinical interest since the first-half of the twentieth century when hyperimmune equine immunoglobulin was first successfully administered to patients with acute and chronic cryptococcal meningitis. Since that time, effective antifungal compounds have been developed, but a much more complex array of host disorders have also emerged creating an even greater need for immunotherapy in conjunction with conventional antifungal therapy. In this review, the scientific foundation supporting the use of various immunotherapeutic interventions including granulocyte infusions, cytokine growth factors, pro-inflammatory cytokines including IFN-gamma and interleukin-12, immunoglobulin therapy, and active immunization will be discussed. Clinical data supporting the use of these interventions are often scant and inconclusive, however, relevant clinical information will be presented. In theory, adjunctive immunotherapy for invasive fungal infections has significant potential for improving clinical outcomes in a growing population of patients at risk for these potentially devastating infections. Clearly, randomized double-blind clinical trials will need to be performed to better understand the precise role of these interventions. There are several obstacles preventing the conduct of these studies, but these pressing clinical issues must be addressed through carefully considered study design and effective implementation.

Autologous transplantation for diffuse aggressive non-Hodgkin lymphoma in first relapse or second remission.

We evaluated the results of high-dose chemotherapy and autologous hematopoietic stem cell transplantation in patients with diffuse aggressive non-Hodgkin lymphoma (NHL) in first relapse (Rel 1) or second complete remission (CR 2). Data were evaluated from the Autologous Blood and Marrow Transplant Registry on 429 patients with diffuse aggressive NHL who underwent transplantation in Rel 1 or CR 2. Transplantations were performed between 1989 and 1996 and were reported to the Autologous Blood and Marrow Transplant Registry by 93 centers in North and South America. The probability of 3-year survival was 44% (95% confidence interval [CI], 33%-55%). The probability at 3 years of progression-free survival was 31% (95% CI, 27%-36%). Patients who underwent transplantation in CR 2 had a 3-year probability of progression-free survival of 38% (95% CI, 30%-46%) compared with 28% (95% CI, 22%-33%) for those who were not in remission at the time of transplantation (P <.001). In multivariate analysis, chemotherapy resistance, increased lactic dehydrogenase at diagnosis, an interval of <12 months from diagnosis to relapse, age >or=40 years, and use of myeloid growth factors to accelerate posttransplantation bone marrow recovery were adverse predictors of survival. High-dose chemotherapy and autologous hematopoietic stem cell transplantation for patients with diffuse aggressive NHL in CR 2 or Rel 1 resulted in better outcome for patients with chemotherapy-sensitive disease, longer relapse-free intervals, and age <40 years. Exposure to myeloid growth factors to accelerate recovery for recipients of bone marrow grafts may increase the risk of disease progression or death.

Risk for the development of treatment-related acute myelocytic leukemia and myelodysplastic syndrome among patients with breast cancer: review of the literature and the National Surgical Adjuvant Breast and Bowel Project experience.

Regimens of adjuvant chemotherapy for early-stage breast cancer commonly include alkylating agents and anthracyclines. These agents have been associated with treatment-related acute myelocytic leukemia (AML) or myelodysplastic syndrome (MDS). This article reviews the medical literature concerning the incidence, causes, and natural history of treatment-related AML/MDS, with emphasis on the association of these factors with alkylating agents, topoisomerase inhibitors, growth factors, and radiation treatment. Data from 6 completed adjuvant National Surgical Adjuvant Breast and Bowel Project trials that tested regimens containing doxorubicin and cyclophosphamide were reviewed to characterize the incidence of treatment-related AML/MDS. The regimens differed in cyclophosphamide intensity, cumulative cyclophosphamide dose, and the presence or absence of mandated prophylactic support with growth factor and ciprofloxacin. Rates were compared across regimens, by patient age, and by treatment with or without adjuvant in-breast radiation therapy (RT). The relative risk (RR) for the development of treatment-related AML/MDS was greater for patients undergoing the more-intense regimens than for those undergoing standard AC (doxorubicin/cyclophosphamide) regimens (RR, 6.16; P<0.0001). Risk correlated more closely with dose intensity than with cumulative dose, and the data suggested that granulocyte colony-stimulating factor (G-CSF) dose may also be independently correlated with increased risk. Patients who received in-breast RT experienced more secondary AML/MDS than those who did not (RR, 2.38; P=0.006). Patients treated with AC with intensified doses of cyclophosphamide requiring G-CSF support had increased rates of treatment-related AML/MDS, even though the incidence was slight relative to breast cancer relapse. In-breast RT appeared to be associated with an increased risk of AML/MDS.

Successful bone marrow plus cord blood stem cell transplantation in a girl who developed myelodysplastic syndrome from hepatitis-associated aplastic anemia treated with long-term immunosuppressants and growth factors.

A 9-year-old girl who had hepatitis-associated aplastic anemia was treated intermittently with methylprednisolone pulse therapy and growth factors (granulocyte-colony stimulating factor (G-CSF), recombinant human erythropoietin (rhEpo) and cyclosporin A (CyA) for over two years. At this time, there was hematological improvement, but chromosome analysis revealed monosomy 7. After six months, there was progression to myelodysplastic syndrome (MDS) (stage in refractory anemia of excess blasts (RAEB)) with monosomy 7, monosomy 6, marker chromosome and with hematological deterioration. She received bone marrow (1.57 x 10(5) cells kg(-1) (patient body weight)) plus cord blood cell (0.3 x 10(7) cells kg(-1) (patient body weight)) transplantation from her brother, 2 years and 7 months after the diagnosis of hepatitis-associated aplastic anemia. Engraftment was achieved after two weeks, and acute graft-versus-host disease occurred in a mild form after four weeks. Hematological remission has been continuous for 20 months after bone marrow transplantation. Transformation of hepatitis-associated aplastic anemia to MDS with the monosomy 7, monosomy 6 and marker chromosome in this patient was considered to have been related to the administration of high doses of immunosuppressive drugs plus growth factors.

Stem cell transplantation and hematopoietic growth factors.

Hematopoietic growth factors are commonly used in allogeneic and autologous stem cell transplantation. The growth factors most frequently used are human recombinant erythropoietin, filgrastim, and sargramostim, and a number of trials have been done using them either singly or in various combinations for mobilization, post-transplant, and for delayed engraftment. Filgrastim and sargramostim can shorten the neutropenic period and decrease infectious complications post-transplant, thus lowering the cost of both autologous and allogeneic transplants. Erythropoietin has not been particularly effective for mobilization, and studies have not shown its efficacy in reducing red blood cell transfusions in autologous transplants. However, they have been clinically beneficial in allogeneic transplantation and in delayed erythropoiesis post-transplantation. Stem cell factor remains investigational at this time but seems promising. The new long-acting erythropoietin and filgrastim are also introduced here and briefly discussed.

An update on angiogenesis therapy.

Angiogenesis is a novel approach for the therapy of various ischemia-related pathophysiologic conditions. Proangiogenic growth factors have shown promising results in preclinical studies using protein- and gene-based therapies. However, their success in clinical trials is hindered by the lack of an optimal delivery strategy that would provide sustained and localized levels of the growth factors in the diseased tissue. Targeted delivery of proangiogenic agents is expected to demonstrate therapeutic efficacy of growth factors at relatively lower doses, without the risk of systemic toxicity in terms of unwanted angiogenesis. To achieve the above objectives, various drug delivery systems are under investigation. This review describes the basic mechanism of action of growth factors, their current status in preclinical and clinical studies, and the issue of drug delivery.

Therapeutic interventions for enhancing collateral development by administration of growth factors: basic principles, early results and potential hazards.

The importance of spontaneously developing collateral vessels to supplement perfusion of tissue rendered ischemic by vascular obstruction was recognized many years ago. However, it was not until potent angiogenesis factors were identified, purified, and produced in sufficient quantities, that the field began its rapid development. In the early 1990s it was first shown that basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) proteins could actually stimulate collateral flow. However, additional studies also demonstrated that the duration of exposure of the vessels to angiogenesis factors was critical, and that the administration of proteins, with their relatively brief half-lives, may pose important practical limitations. The demonstration that gene therapy can improve collateral function presents one of the solutions to the conundrum, since gene therapy can be considered a sophisticated form of a sustained delivery system. The results of several clinical trials have been reported. All involve administration of single angiogenesis agents, and most are Phase I trials. The two studies rising to Phase II status demonstrated no treatment effect on the primary end-point. It may therefore be relevant to consider that the molecular mechanisms responsible for angiogenesis are extraordinarily complex, and an optimal angiogenesis intervention may require a 'multiple factor' strategy. It is important to note that no serious side-effects ascribable to an angiogenesis agent were recognized in these trials. However, angiogenesis agents are potent molecules with multiple activities. It is therefore possible that they might occasionally cause side-effects, some serious. Among these, based on their biologic activities, are neovascularization of non-targeted tissues, expansion and induction of instability of atherogenic plaque, and growth of tumors. In summary, there is ample experimental evidence justifying an optimistic outlook relating to our eventually being successful in enhancing collateral flow to ischemic tissue in a clinical setting. However, we are not there yet, and identification of the optimal angiogenesis strategy is still unclear. Additional experimental work, in parallel with large, carefully controlled clinical trials are needed to continue the exciting advances of the last decade, and to achieve the goal of providing patients with alternative potent therapies to improve collateral flow, and thereby to alleviate their symptoms and perhaps to prolong their lives.

Prospective evaluation of oral mucositis in patients receiving myeloablative conditioning regimens and haemopoietic progenitor rescue.

Four hundred and twenty-nine patients received myeloablative chemotherapy for solid and haematological malignancies in a bone marrow transplantation unit. Regimens appropriate to the tumour type were administered and haemopoietic reconstitution was achieved with peripheral blood progenitor cells (PBPC; n = 275), autologous bone marrow (auto-BMT; n = 69) or allogeneic bone marrow (allo-BMT; n = 85). World Health Organization (WHO) oral mucositis scores were collected prospectively from the start of chemotherapy (d 1) until d 28 or discharge. Oral mucositis (OM) was experienced by 425 (99%) patients and in 289 (67.4%) this was grade III or IV. Strong opiate analgesia was prescribed for a median of 6 d to 47% of patients. Univariate analysis suggested that the area under the OM curve (AUC; sum of daily mucositis grades, d 1-28) was associated with the myeloablative regimen, haemopoietic progenitor source (PBPC > allo-BMT > auto-BMT), use of myeloid growth factors and age. Multivariate analysis showed that the only independent risk factor for mucositis was the conditioning regimen (P < 0.00005). The mean OM AUC for high-dose melphalan (HDM) regimens (52 grade-days) exceeded busulphan (41), busulphan-cyclophosphamide (35), cyclophosphamide-total body irradiation (TBI) (34), cyclophosphamide-carmustine (BCNU) (20) and cyclophosphamide-etoposide-carmustine (CVB) (19). HDM regimens resulted in the highest mean peak OM (3.6), followed by busulphan regimens (2.6), cyclophosphamide/TBI (2.3) and cyclophosphamide-carmustine and CVB (1.4). Busulphan produced significantly delayed OM (median 3 d; P < 0.00005). There was a linear association between the area under the OM curve for each treatment group and the time to reach grade 3 OM (P < 0.00005), but no association with the time to reach grade 4 neutropenia (P = 0.24) or thrombocytopenia (P = 0.73), implying that haematological and mucosal toxicity are not associated. The cytotoxic regimen is the most significant determinant of OM. Studies investigating agents to ameliorate mucosal toxicity should be stratified according to cytotoxic regimen.