Epithelial Keratins Modulate cMet Expression and Signaling and Promote InlB-Mediated Listeria monocytogenes Infection of HeLa Cells.

The host cytoskeleton is a major target for bacterial pathogens during infection. In particular, pathogens usurp the actin cytoskeleton function to strongly adhere to the host cell surface, to induce plasma membrane remodeling allowing invasion and to spread from cell to cell and disseminate to the whole organism. Keratins are cytoskeletal proteins that are the major components of intermediate filaments in epithelial cells however, their role in bacterial infection has been disregarded. Here we investigate the role of the major epithelial keratins, keratins 8 and 18 (K8 and K18), in the cellular infection by Listeria monocytogenes. We found that K8 and K18 are required for successful InlB/cMet-dependent L. monocytogenes infection, but are dispensable for InlA/E-cadherin-mediated invasion. Both K8 and K18 accumulate at InlB-mediated internalization sites following actin recruitment and modulate actin dynamics at those sites. We also reveal the key role of K8 and K18 in HGF-induced signaling which occurs downstream the activation of cMet. Strikingly, we show here that K18, and at a less extent K8, controls the expression of cMet and other surface receptors such TfR and integrin ß1, by promoting the stability of their corresponding transcripts. Together, our results reveal novel functions for major epithelial keratins in the modulation of actin dynamics at the bacterial entry sites and in the control of surface receptors mRNA stability and expression.

Carboplatin in the treatment of Ewing sarcoma: Results of the first Brazilian collaborative study group for Ewing sarcoma family tumors-EWING1.

BACKGROUND: Large cooperative group studies have shown the efficacy of risk-adapted treatment for Ewing sarcoma. However, validation and local adaptation by National cooperative groups is needed. A multicenter protocol to determine the efficacy and safety of a risk-adapted intensive regimen was developed by the Brazilian cooperative group. PROCEDURE: Patients <30 years old with Ewing sarcoma were eligible. Induction chemotherapy consisted of two cycles of ICE (ifosfamide, carboplatin, and etoposide) followed by two cycles of VDC (vincristine, doxorubicin, and cyclophosphamide), followed by local control. Patients with low risk (LR) disease (localized resectable with normal LDH) received 10 additional alternating courses of IE with VDC. For patients with high-risk (HR) disease (unresectable, pelvic, metastatic, or high LDH), two additional cycles of ICE were given. RESULTS: One-hundred seventy five patients (39% metastatic) were enrolled. Fifty-two patients (29.7%) were LR and 123 (70.3%) were HR. Overall response rate at end of induction was 27.4%. Five-year event-free survival (EFS) and overall survival (OS) estimates were 51.4% and 54.4%, respectively. Patients with localized disease had better outcomes than patients with metastases (5-year EFS 67.9% vs. 25.5%, and 5-year OS 70.3% vs. 29.1%, respectively). On multivariate analysis, the presence of metastatic disease was the only prognostic factor (P < 0.01). CONCLUSION: The VDC/ICE protocol was feasible, and considering the high tumor burden in our population, resulted in comparable results to those reported by cooperative groups in high-income countries. Further adaptation to maximize efficacy and minimize toxicity will be required.

Mature autologous dendritic cell vaccines in advanced non-small cell lung cancer: a phase I pilot study.

BACKGROUND: Overall therapeutic outcomes of advanced non-small-cell lung cancer (NSCLC) are poor. The dendritic cell (DC) immunotherapy has been developed as a new strategy for the treatment of lung cancer. The purpose of this study was to evaluate the feasibility, safety and immunologic responses in use in mature, antigen-pulsed autologous DC vaccine in NSCLC patients. METHODS: Five HLA-A2 patients with inoperable stage III or IV NSCLC were selected to receive two doses of 5 × 107 DC cells administered subcutaneous and intravenously two times at two week intervals. The immunologic response, safety and tolerability to the vaccine were evaluated by the lymphoproliferation assay and clinical and laboratorial evolution, respectively. RESULTS: The dose of the vaccine has shown to be safe and well tolerated. The lymphoproliferation assay showed an improvement in the specific immune response after the immunization, with a significant response after the second dose (p = 0.005). This response was not long lasting and a tendency to reduction two weeks after the second dose of the vaccine was observed. Two patients had a survival almost twice greater than the expected average and were the only ones that expressed HER-2 and CEA together. CONCLUSION: Despite the small sample size, the results on the immune response, safety and tolerability, combined with the results of other studies, are encouraging to the conduction of a large clinical trial with multiples doses in patients with early lung cancer who underwent surgical treatment. TRIAL REGISTRATION: Current Controlled Trials: ISRCTN45563569.

Intracaval and intracardiac extension of Wilms' tumor. The influence of preoperative chemotherapy on surgical morbidity.

OBJECTIVES: The aim of this retrospective study is to compare surgical complications and long-term survival in children with Wilms' tumor (WT) and tumor thrombus receiving or not preoperative chemotherapy. MATERIALS AND METHODS: Review of the charts of 155 children with WT treated between 1983 and 2005, and analysis of 16/155 (10.3%) children with WT who presented cavoatrial tumor extension, being 8/16 IVC and 8/16 atrial thrombus. RESULTS: Median age was 54 months. 2/16 had cardiac failure as the first symptom. 11/16(7 IVC and 4 atrial extension) (67%) were submitted to preoperative chemotherapy with vincristine plus actinomycin D, and 5/16(1 IVC and 4 atrial) (33%) underwent initial nephrectomy and thrombus resection. So, 11 patients were submitted to preoperative VCR/ACTD and 2/11 (18.1%) had complete regression of the thrombus, 6/11(54.5%) partial regression and 3/11 (27%) had no response. Among the partial responders, nephrectomy with thrombus removal was performed in all, including one patient with previous intracardiac involvement, without extracorporeal circulation procedures. In two of the three non-responders, cardiopulmonary bypass was necessary for thrombus removal. There were no surgical related deaths. Long-term survival is 91% in the group submitted to preoperative chemotherapy and 100% in the group who had surgery as first approach. CONCLUSION: Preoperative chemotherapy was able to reduce thrombus extension in 8/11 (73%) treated patients and cardiopulmonary bypass was avoided in 2 patients with atrial thrombus. Surgical resection of tumor and thrombus was successful in all cases, receiving or not preoperative chemotherapy and overall survival was similar in both groups.

Intracaval and intracardiac extension of Wilms' tumor: the influence of preoperative chemotherapy on surgical morbidity

OBJECTIVES: The aim of this retrospective study is to compare surgical complications and long-term survival in children with Wilms' tumor (WT) and tumor thrombus receiving or not preoperative chemotherapy MATERIALS AND METHODS: Review of the charts of 155 children with WT treated between 1983 and 2005, and analysis of 16/155 (10.3 percent) children with WT who presented cavoatrial tumor extension, being 8/16 IVC and 8/16 atrial thrombus RESULTS: Median age was 54 months. 2/16 had cardiac failure as the first symptom. 11/16(7 IVC and 4 atrial extension) (67 percent) were submitted to preoperative chemotherapy with vincristine plus actinomycin D, and 5/16(1 IVC and 4 atrial) (33 percent) underwent initial nephrectomy and thrombus resection. So, 11 patients were submitted to preoperative VCR/ACTD and 2/11 (18.1 percent) had complete regression of the thrombus, 6/11(54.5 percent) partial regression and 3/11 (27 percent) had no response. Among the partial responders, nephrectomy with thrombus removal was performed in all, including one patient with previous intracardiac involvement, without extracorporeal circulation procedures. In two of the three non-responders, cardiopulmonary bypass was necessary for thrombus removal. There were no surgical related deaths. Long-term survival is 91 percent in the group submitted to preoperative chemotherapy and 100 percent in the group who had surgery as first approach CONCLUSION: Preoperative chemotherapy was able to reduce thrombus extension in 8/11 (73 percent) treated patients and cardiopulmonary bypass was avoided in 2 patients with atrial thrombus. Surgical resection of tumor and thrombus was successful in all cases, receiving or not preoperative chemotherapy and overall survival was similar in both groups.

Measles and rubella antibody status in children after treatment for acute lymphoblastic leukemia

OBJETIVO: Avaliar a história vacinal e a situação da proteção vacinal contra sarampo e rubéola em crianças portadoras de leucemia linfóide aguda após o término do tratamento. MÉTODOS: O estado imunológico contra o sarampo e a rubéola foi avaliado pela técnica ELISA em 22 crianças com leucemia linfóide aguda após o término do tratamento. RESULTADOS: Dos 22 pacientes, 20 haviam recebido previamente duas doses da vacina do sarampo, e 18 deles, uma dose da vacina da rubéola. Soropositivos para sarampo e rubéola resultaram em 65 e 88,9 por cento, respectivamente, sem correlação com idade do paciente, agressividade do tratamento ou tempo decorrido entre final do tratamento e coleta da amostra. CONCLUSÃO: Detectamos falha na proteção vacinal contra sarampo e rubéola em 35 e 11,1 por cento dos casos, respectivamente. Recomendamos, ao final do tratamento para leucemia linfóide aguda, aplicar reforço da vacina contra sarampo, avaliar o estado imunológico contra rubéola e, se necessário, revacinar o paciente.

OBJECTIVE: To assess the vaccination history and the status of vaccine-induced protection from measles and rubella in children after treatment for acute lymphoblastic leukemia. METHODS: Measles and rubella immunological status was assessed by the ELISA technique for 22 children previously treated for acute lymphoblastic leukemia. RESULTS: From the total of 22 patients, 20 had been given two doses of measles vaccine and 18 had had one dose of rubella vaccine. The percentage of patients seropositive for measles and rubella were 65 and 88.9 percent, respectively, with no correlation with age of patient, aggression of treatment or the time passed between the end of treatment and sample collection. CONCLUSIONS: We detected that vaccination had failed against measles and rubella in 35 and 11.1 percent of cases, respectively. We recommend that a measles booster be given after the completion of treatment for acute lymphoblastic leukemia and that rubella immunity status should be assessed at this point, with revaccination performed when necessary.

Measles and rubella antibody status in children after treatment for acute lymphoblastic leukemia.

OBJECTIVE: To assess the vaccination history and the status of vaccine-induced protection from measles and rubella in children after treatment for acute lymphoblastic leukemia. METHODS: Measles and rubella immunological status was assessed by the ELISA technique for 22 children previously treated for acute lymphoblastic leukemia. RESULTS: From the total of 22 patients, 20 had been given two doses of measles vaccine and 18 had had one dose of rubella vaccine. The percentage of patients seropositive for measles and rubella were 65 and 88.9%, respectively, with no correlation with age of patient, aggression of treatment or the time passed between the end of treatment and sample collection. CONCLUSIONS: We detected that vaccination had failed against measles and rubella in 35 and 11.1% of cases, respectively. We recommend that a measles booster be given after the completion of treatment for acute lymphoblastic leukemia and that rubella immunity status should be assessed at this point, with revaccination performed when necessary.

Ulcerated rhabdomyosarcoma as portal of entry for tetanus in a previously nonimmunized child.

Infectious diseases represent one of the most important secondary problems related to the treatment of childhood cancer, being the leading cause of death in this population. They are predominantly of bacterial and fungal etiology. The association between tetanus, a bacterial vaccine-preventable disease, and cancer is virtually undescribed. The authors present the case of a previously nonimmunized child, due to his parents' choice, who developed severe tetanus with an ulcerated rhabdomyosarcoma as portal of entry. Due to an unfavorable evolution, the child underwent a hip disarticulation to provide tetanus control. The ulterior tumor management was successful: the child has been off therapy for more than 108 months with no evidence of disease.

Ultrastructural studies on the in vitro interaction of Trypanosoma cruzi bloodstream forms and mouse peritoneal macrophages.

Macrophages are normally host cells for T. cruzi in the vertebrate host. Since the process of interiorization of this parasite into those cells is still controversial, we decided to investigate by electron microscopy the in vitro uptake of T. cruzi bloodstream forms by mouse peritoneal macrophages. After 15 min of interaction with macrophages, parasites are interiorized by a process of phagocytosis in which both parasite and host cell seem to play a specific role. Sequential steps of the uptake process and the simultaneous ultrastructural alterations of the host cell morphology have been studied. A dense amorphous substance interposed between the parasite and the macrophage surface was regularly observed. Although its origin, significance and nature remain unknown, we discuss the possibility that it might be released extracellularly by the macrophage in response to the parasite stimulation.