RESUMO
BACKGROUND: There is no consensus on the second-line treatment of patients with progressive high-grade neuroendocrine neoplasms (NENs G3) and large-cell lung neuroendocrine carcinoma. These patients generally have poor performance status and low tolerance to combination therapy. In this trial, we aim to evaluate the efficacy and safety of temozolomide given every other week in patients with advanced platinum-pretreated NENs G3. PATIENTS AND METHODS: This trial is an open-label, non-randomized, phase II trial. Patients with platinum-pretreated metastatic neuroendocrine carcinoma were treated with 75 mg/m2/day of temozolomide for 7 days, followed by 7 days of no treatment (regimen one week on/one week off). The primary endpoint was the overall response rate. Secondary endpoints included progression-free survival (PFS), overall survival (OS), safety and tolerability. This study is registered with ClinicalTrials.gov, NCT04122911. RESULTS: From 2017 to 2020, 38 patients were enrolled. Among the patients with determined Ki67, 12 out of 36 (33.3%) had a Ki67 index <55% and the remaining 24 out of 36 (66.6%) had an index ≥55%. Overall response rate was 18% (7/38), including one complete response and six partial responses. The median PFS was 5.86 months [95% confidence interval (CI) 4.8 months-not applicable) and the median OS was 12.1 months (95% CI 5.6-20.4 months). The 1-year PFS rate was 37%. No statistically significant difference in median PFS [hazard ratio 1.3 (95% CI 0.6-2.8); P = 0.44] and median OS [hazard ratio 1.1 (95% CI 0.5-2.4); P = 0.77] was observed among patients with Ki67 <55% versus ≥55%. Only G1-G2 adverse events were registered, the most common being G1 nausea, diarrhea and abdominal pain. CONCLUSION: One week on/one week off temozolomide shows promising activity in patients with poorly differentiated NEN. The good safety profile confirmed the possibility of using this scheme in patients with poor performance status.
Assuntos
Carcinoma Neuroendócrino , Temozolomida , Humanos , Masculino , Temozolomida/uso terapêutico , Temozolomida/farmacologia , Feminino , Pessoa de Meia-Idade , Carcinoma Neuroendócrino/tratamento farmacológico , Idoso , Adulto , Antineoplásicos Alquilantes/uso terapêutico , Antineoplásicos Alquilantes/farmacologia , Esquema de Medicação , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Intervalo Livre de ProgressãoRESUMO
The introduction of highly active antiretroviral therapy (ART) has deeply modified the outcome of HIV patients by improving their overall survival and ameliorating their quality of life (QoL). The prolongation of these patients' survival has led to an increased risk of highly diffused non-infectious diseases, e.g., cardiovascular diseases, endocrine disease, neurological diseases, and cancer. The management of antiretroviral therapy and anticancer agents (AC) can be challenging, due to the possible drug-drug interactions (DDI) between AC and ART. For this reason, a multidisciplinary approach is always preferred as demonstrated by the GICAT (Italian Cooperation Group on AIDS and Tumors). This review aims to analyze the current scientific data regarding the possible effects of ART on the management of HIV-positive cancer patients and to evaluate the possible DDIs that must be taken into consideration when co-administrating ART and AC. A collaboration between all the involved professional figures, particularly infectious disease specialists and oncologists, represents the key to the correct managing of these patients in order to guarantee the best oncological outcome possible.
Assuntos
Infecções por HIV , Neoplasias , Humanos , Infecções por HIV/tratamento farmacológico , Qualidade de Vida , Neoplasias/tratamento farmacológico , Terapia Antirretroviral de Alta Atividade , Quimioterapia CombinadaRESUMO
The imaging has critical responsibility in the assessment of peritoneal lesions along with estimating the overall extent. Valuing disease burden is crucial for selection of combining cytoreductive surgery (CRS) and intraperitoneal hyperthermic chemotherapy (HIPEC) treatment. An approach that combines the strength of several imaging tools and increases diagnostic accuracy, should be chosen, even if the preferred imaging tool in patients with suspected Peritoneal Carcinomatosis (PC) is CT. The outcomes of PC are mainly correlated to tumor spread, localization, and lesion size. Accurate assessment of these features is critical for prognosis and treatment planning. These data can be evaluated by Peritoneal Cancer Index (PCI), a quantitative index suggested by Harman and Sugarbaker. Additionally, precise predictive biomarkers should be established to predict PC in patients at risk. The radiomics analysis could predict PC throughout the evaluation of cancers heterogeneity.
Assuntos
Hipertermia Induzida , Neoplasias Peritoneais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Procedimentos Cirúrgicos de Citorredução , Humanos , Hipertermia Induzida/métodos , Quimioterapia Intraperitoneal Hipertérmica , Neoplasias Peritoneais/diagnóstico por imagem , Neoplasias Peritoneais/terapiaRESUMO
BACKGROUND: Preoperative treatment of resectable liver metastases from colorectal cancer (CRC) is a matter of debate. The aim of this study was to assess the feasibility and activity of bevacizumab plus FOLFIRI in this setting. METHODS: Patients aged 18-75 years, PS 0-1, with resectable liver-confined metastases from CRC were eligible. They received bevacizumab 5 mg kg(-1) followed by irinotecan 180 mg m(-)(2), leucovorin 200 mg m(-)(2), 5-fluorouracil 400 mg m(-)(2) bolus and 5-fluorouracil 2400 mg m(-)(2) 46-h infusion, biweekly, for 7 cycles. Bevacizumab was stopped at cycle 6. A single-stage, single-arm phase 2 study design was applied with 1-year progression-free rate as the primary end point, and 39 patients required. RESULTS: From October 2007 to December 2009, 39 patients were enrolled in a single institution. Objective response rate was 66.7% (95% exact CI: 49.8-80.9). Of these, 37 patients (94.9%) underwent surgery, with a R0 rate of 84.6%. Five patients had a pathological complete remission (14%). Out of 37 patients, 16 (43.2%) had at least one surgical complication (most frequently biloma). At 1 year of follow-up, 24 patients were alive and free from disease progression (61.6%, 95% CI: 44.6-76.6). Median PFS and OS were 14 (95% CI: 11-24) and 38 (95% CI: 28-NA) months, respectively. CONCLUSION: Preoperative treatment of patients with resectable liver metastases from CRC with bevacizumab plus FOLFIRI is feasible, but further studies are needed to define its clinical relevance.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/cirurgia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bevacizumab , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Quimioterapia Adjuvante , Neoplasias Colorretais/patologia , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Humanos , Estimativa de Kaplan-Meier , Leucovorina/administração & dosagem , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Taxa de SobrevidaRESUMO
BACKGROUND: Almost 30% of the sunitinib-treated patients for metastatic renal carcinoma (mRCC) do not receive a clinical benefit. Convincing evidences demonstrated a cross talk between the VEGF and CXCR4 pathways. It was hypothesized that CXCR4 expression in primary renal cancer could predict sunitinib responsiveness. PATIENTS AND METHODS: In this exploratory study sixty-two mRCC patients receiving sunitinib as first-line treatment were evaluated for CXCR4 expression through immunohistochemistry (IHC). Correlations between CXCR4 expression, baseline patients and tumour characteristics were studied by contingency tables and the chi-square test. Univariable analysis was performed with the log-rank test, and the Cox model was applied for multivariable analysis. RESULTS: The objective response rate of sunitinib first-line therapy was 35.5% (22/62) with a disease control rate (response and stable disease) of 62.9% (39/62). CXCR4 expression was absent/low in 30 (48.4%), moderate in 17 (27.4%), and high in 15 (24.2%) tumors respectively. Low or absent CXCR4 expression predicted response to sunitinib therapy. Moreover, Fuhrman grading and concomitant, CXCR4 and Fuhrman grading, strongly predicted sunitinib first line therapy responsiveness on progression-free survival and overall survival. CONCLUSIONS: High CXCR4 expression correlates with sunitinib poor response in metastatic renal cancer.
Assuntos
Inibidores da Angiogênese/uso terapêutico , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/imunologia , Indóis/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/imunologia , Pirróis/uso terapêutico , Receptores CXCR4/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/secundário , Linhagem Celular Tumoral , Distribuição de Qui-Quadrado , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Itália , Estimativa de Kaplan-Meier , Neoplasias Renais/genética , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Gradação de Tumores , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , RNA Mensageiro/metabolismo , Receptores CXCR4/genética , Medição de Risco , Fatores de Risco , Sunitinibe , Fatores de Tempo , Resultado do TratamentoRESUMO
CXCR4 is a chemokine receptor implicated in the metastatic process. The CXCR4 ligand, CXCL12, was shown to bind also the CXCR7 receptor, a recently deorphanized chemokine receptor whose signalling pathway and function are still controversial. This study was conducted to determine patients clinic-pathological factors and outcome according to the expressions of CXCR4 and CXCR7 in renal cell carcinoma (RCC). CXCR4 and CXCR7 expression was evaluated in 223 RCC patients through immunohistochemistry; moreover CXCR4 and CXCR7 was detected in 49 others consecutive RCC patients trough RT- PCR. CXCR4 expression was low in 42/223 RCC (18.8%), intermediate in 71/223 (31.9%) and high in 110/223 (49.3%). CXCR7 expression was low in 44/223 RCC patients (19.8%), intermediate in 65/223 (29.1%) and high in 114/223 (51.1%). High CXCR4 and high CXCR7 expression predicted shorter disease free survival. In multivariate analysis, high CXCR4 expression (p= 0.0061), high CXCR7 (p= 0.0194) expression and the concomitant high expression of CXCR4 and CXCR7 (p= 0.0235) are independent prognosis factors. Through RT-PCR, CXCR4 was overexpressed in 36/49 and CXCR7 in 33/49 samples correlating with symptoms at diagnosis and lymph nodes status. So we can hypothesize that CXCR4 and CXCR7, singularly evaluated and in combination, are valuable prognostic factors in RCC patients.
Assuntos
Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/metabolismo , Neoplasias Renais/diagnóstico , Neoplasias Renais/metabolismo , Receptores CXCR4/metabolismo , Receptores CXCR/metabolismo , Idoso , Envelhecimento , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/secundário , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Rim/metabolismo , Rim/patologia , Neoplasias Renais/patologia , Metástase Linfática , Masculino , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/metabolismo , Receptores CXCR/genética , Receptores CXCR4/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de SobrevidaRESUMO
The standard treatment of CRC patients with hepatic metastases is systemic chemotherapy; however, 5-year survival is disappointingly poor despite recent advances. On the other hand, in patients who undergo immediate radical surgical resection of hepatic metastases, 5-year survival reaches 30-40%. Unfortunately, only 15-20% of patients with hepatic metastases are initially eligible for a radical surgical approach. The majority of patients undergoing liver resection relapse after surgery. For this reason, new onco-surgery approaches have been investigated in recent years and the addition of biological agents to chemotherapy, such as bevacizumab and cetuximab, and the improvements of surgical techniques have opened a new scenario in the management of colorectal liver metastases. Recently, the EORTC trial has demonstrated that perioperative chemotherapy (Folfox regimen) is feasible and improves progression-free survival in patients with resectable liver metastases. Chemotherapy and surgery can finally collaborate. In the unresectable setting, the association of chemotherapy with bevacizumab and cetuximab is particularly promising in improving resectability rate. In particular, K-RAS is a molecular response predictive factor that could be particularly useful in selecting the best treatment option in patients with unresectable liver disease.
Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Quimioterapia Adjuvante , Ensaios Clínicos como Assunto , Terapia Combinada , Humanos , Neoplasias Hepáticas/cirurgia , Cuidados Pré-Operatórios , Estudos Prospectivos , Estudos RetrospectivosRESUMO
Current management of bone metastases involves a multimodal approach. Aminobisphosphonates (BPs) are a valid weapon in the treatment of skeletal localization of tumour disease. Patients with bone metastases from breast and lung cancer were enrolled in order to evaluate the impact of the addition of bisphosphonates therapy to standard treatments in terms of (i) pain control, (ii) quality of life (QoL) and (iii) toxicity and to evaluate (iv) any relations between clinical activity and the occurrence of SREs. A total of 60 patients were included in the study. Median age was 76 years (range 40-83). The majority of patients were treated with chemotherapy or hormonal therapy. All patients received zoledronic acid (ZOL) (4 mg) every 3-4 weeks for at least 3 cycles. No significant improvement in Performance Status of patients after 12 cycles of ZOL (p = 0.1672) was recorded. A statistically significant early and long-lasting amelioration of both pain, narcotic scores and QoL was found. Twenty-one patients (48%) experienced at least one SRE during the study. The most common SRE was radiation to bone (30% of patients). An inverse correlation between bone tumour response and SREs was also found (p = 0.019). ZOL addition induces a clinical benefit and improves QoL of patients with bone metastases. Moreover, the occurrence of bone clinical response is related to a reduced risk of SREs.
Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Neoplasias Ósseas/secundário , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Difosfonatos/uso terapêutico , Imidazóis/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/efeitos adversos , Difosfonatos/administração & dosagem , Difosfonatos/efeitos adversos , Feminino , Humanos , Imidazóis/administração & dosagem , Imidazóis/efeitos adversos , Masculino , Pessoa de Meia-Idade , Sistema Musculoesquelético/efeitos dos fármacos , Qualidade de Vida , Ácido ZoledrônicoAssuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Oncologia/normas , Neoplasias/tratamento farmacológico , Humanos , Neoplasias/classificação , Neoplasias/patologia , Estudos RetrospectivosAssuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Terapia Neoadjuvante , Sarcoma/tratamento farmacológico , Neoplasias de Tecidos Moles/tratamento farmacológico , Terapia Combinada , Avaliação de Medicamentos , Epirubicina/administração & dosagem , Seguimentos , Humanos , Ifosfamida/administração & dosagem , Estudos Retrospectivos , Sarcoma/patologia , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/patologia , Neoplasias de Tecidos Moles/cirurgia , Resultado do TratamentoRESUMO
BACKGROUND: Carboplatin is a milestone drug against ovarian carcinoma; it is used both in front-line and second-line chemotherapy. Hypersensitivity reactions to carboplatin may occur during the treatment as salvage therapy. The purpose of this study was to describe the feasibility of the replacing of carboplatin with cisplatin in patients presenting with severe hypersensitivity reactions to carboplatin. PATIENTS AND METHODS: Ten consecutive patients with platinum-sensitive, recurrent ovarian carcinoma, presenting with moderate/severe hypersensitivity reactions to carboplatin were treated with cisplatin 60 mg/m2 from January 2000 to December 2002. Hypersensitivity reactions consisted of respiratory distress (chest tightness, wheezing, dyspnea), urticaria/erythema with tachycardia, facial swelling and hypotension. RESULTS: The total number of cisplatin cycles given was 44 (range 2-5). The treatment with cisplatin was generally well tolerated. No serious allergic reactions occurred. A mild allergic reaction was recorded (urticaria) in only one case, after one cycle of cisplatin, and the patient was not rechallenged because of progressive disease. No reductions of chemotherapy doses were needed. CONCLUSION: To date, platinum-based regimens remain the most effective treatment in recurrent platinum-sensitive ovarian cancer with a high rate of objective responses. Although our experience is limited, we suggest that, under anesthesiologic surveillance and providing immunologic blockade, the replacement of carboplatin salvage therapy with cisplatin can be considered a safe therapeutic strategy in patients who cannot continue carboplatin due to allergic reactions.
Assuntos
Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Carboplatina/efeitos adversos , Cisplatino/uso terapêutico , Hipersensibilidade a Drogas/etiologia , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Idoso , Carboplatina/uso terapêutico , Cisplatino/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/imunologia , Neoplasias Ovarianas/imunologia , Terapia de SalvaçãoRESUMO
BACKGROUND: CD40, a member of the tumor necrosis factor receptor superfamily, is capable of mediating the induction of apoptosis in tumors including sarcomas. The expression of proapoptotic receptor contribute to the induction of apoptosis by chemotherapeutic drugs. The present study was undertaken to determine if there is a correlation between the expression of CD40 in spindle-cell sarcomas and the response to epirubicin and ifosfamide chemotherapy. PATIENTS AND METHODS: Immunohistochemical analysis of CD40 expression was performed on 59 paraffin-embedded archival tissues. Evaluation of objective tumor response was carried out according to the WHO criteria. Correlations with response to chemotherapy and baseline patients' characteristics were investigated using Chi-square tests. RESULTS: Positive CD40 staining was observed in 42 tumors; it was expressed in < 10% of cells in 14 (24%), in 10 to 50% in 16 (27%) and in more than 50% of cells in 12 (20%) tumors. No significant association was found between CD40 expression, response to chemotherapy and other clinical and pathological characteristics. CONCLUSION: CD40 expression in spindle-cell soft tissue sarcomas is not associated with response to ifosfamide plus epirubicin chemotherapy.
Assuntos
Antígenos de Neoplasias/análise , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígenos CD40/análise , Resistencia a Medicamentos Antineoplásicos , Sarcoma/química , Neoplasias de Tecidos Moles/química , Adulto , Idoso , Epirubicina/administração & dosagem , Epirubicina/farmacologia , Feminino , Humanos , Ifosfamida/administração & dosagem , Ifosfamida/farmacologia , Masculino , Mesna/administração & dosagem , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Resultado do TratamentoRESUMO
BACKGROUND: Neoadjuvant chemotherapy for intermediate/high-grade soft tissue sarcomas (STS) may provide some advantages for facilitating the surgical resection of the tumor and for disease control. However its role as induction therapy before surgery should still be proved. PATIENTS AND METHODS: Twenty-one patients with intermediate/high-grade STS and tumor size > or = 5 cm were consecutively treated from 1997 to 2001 with neoadjuvant chemotherapy based on epirubicin 60 mg/m2/day on days 1 and 2 and ifosfamide 1.8 gr/m2/day on days 1 through 5 every three weeks. Evaluation of objective tumor response and toxicity were carried out according to WHO criteria. RESULTS: Nine partial responses were documented; stable disease in 11 patients, progressive disease in one patient. Apart from nine cases of grade 4 neutropenia, the treatment was generally well-tolerated. Twelve patients underwent conservative and limb salvage surgery. CONCLUSION: This therapeutic approach seems to be effective in facilitating surgery. Neutropenia was the most significant toxicity but it was preventable or medically treatable with G-CSF support.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sarcoma/tratamento farmacológico , Neoplasias de Tecidos Moles/tratamento farmacológico , Adulto , Idoso , Intervalo Livre de Doença , Epirubicina/administração & dosagem , Feminino , Seguimentos , Humanos , Ifosfamida/administração & dosagem , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Sarcoma/patologia , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/patologia , Neoplasias de Tecidos Moles/cirurgiaRESUMO
The present study was designed to determine the molecular mechanisms by which interleukin (IL)-10 prevents the HLA class I antigen expression at the cell surface. In this context, the potential role of transporter associated with antigen presentation 1+2 (TAP1+2) molecules and NF-kappaB transcription factors was addressed. The IL-10 effect was investigated in a human lymphoblastoid cell system defective for TAP1+2 genes (T2 cell line) and in the related TAP1+2 transfectants (T3 cell line). In this experimental system, after 48 h of incubation in the presence of IL-10, the HLA class I antigen downmodulation was observed in the T3 but not in the T2 cell line, suggesting a potential role of TAP1+2 molecules. In the same experimental conditions, the NF-kappaB activity was unaffected. Instead, after 3 h of exposure to IL-10, the HLA downmodulation was observed in both cell lines, the NF-kappaB factors activity being strongly reduced. In addition, the transfection of the inhibitor of NF-kappaB, IkappaBalpha, prevented the IL-10 effect on HLA class I antigen expression in the T3 cell line. This phenomenon was observed after 3 h but not 48 h of IL-10 incubation. These evidences indicate a time dependent involvement of TAP1+2 antigens and of NF-kappabeta activity in the IL-10-induced major histocompatibility complex (MHC) class I downmodulation.
Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Interleucina-10/farmacologia , NF-kappa B/metabolismo , Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Membro 3 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/imunologia , Anticorpos Monoclonais , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/imunologia , Citometria de Fluxo , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/imunologia , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Interleucina-10/imunologia , NF-kappa B/genética , NF-kappa B/imunologia , Sondas de Oligonucleotídeos , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , TransfecçãoRESUMO
Recent studies demonstrate that the rotavirus nonstructural protein NSP4 functions as an enterotoxin and plays an important role in viral pathogenesis. Previous in vitro studies of NSP4 have used a cDNA clone of gene 10 derived from the prototypic rotavirus strain, SA11. We recently compared the sequence of the commonly used NSP4 cDNA with the sequence obtained from several SA11 isolates by direct sequencing of reverse transcription polymerase chain reaction products. One codon difference was identified between the cDNA clone and the SA11 virus isolates, and this resulted in a predicted amino acid substitution at position 47. The cDNA sequence specifies an asparagine at position 47, and the SA11 virus gene 10 encodes a hisitidine. To determine if this amino acid substitution altered the function of NSP4, we analyzed the ability of both NSP4-Asn47 and NSP4-His47 to regulate intracellular calcium levels and exhibit cell cytotoxicity. Our results indicate that the expression of NSP4-His47 from a recombinant baculovirus displays enhanced cytotoxicity and calcium flux.
Assuntos
RNA Polimerases Dirigidas por DNA , Rotavirus/genética , Proteínas não Estruturais Virais/genética , Substituição de Aminoácidos , Asparagina/química , Baculoviridae/genética , Western Blotting , Cálcio/metabolismo , Linhagem Celular , Códon , DNA Complementar/análise , Histidina/química , Proteínas Recombinantes/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rotavirus/química , Proteínas não Estruturais Virais/biossíntese , Proteínas não Estruturais Virais/químicaRESUMO
NK cells can recognize and kill tumor as well as certain normal cells. The outcome of the NK-target interaction is determined by a balance of positive and negative signals initiated by different target cell ligands. We have previously shown that human NK cells kill CD40-transfected tumor targets efficiently, but the physiological significance of this is unclear. We now demonstrate that human NK cells can kill dendritic cells (DC), known to express CD40 and other co-stimulatory molecules. The killing was observed with polyclonal NK cells cultured short term in IL-2 as well as with NK cell clones as effectors, and with allogeneic as well as autologous DC as targets. NK cell recognition could be inhibited, but only partially, by preincubation of target cells with monoclonal antibodies against CD40, suggesting that this molecule may be one of several ligands involved. Addition of TNF-alpha of the cultures stimulated the development of a more mature DC phenotype, while addition of IL-10 resulted in a less mature phenotype, with lower expression of CD40 and other co-stimulatory molecules. Nevertheless, such DC were more NK susceptible than the differentiated DC. This may be partly explained by a reduced MHC class I expression observed on such cells, since blocking of MHC class I molecules on differentiated DC or CD94 receptors of NK cells led to increased NK susceptibility. The results show that NK cells may interact with DC, and suggest that the outcome of such interactions depend on the cytokine milieu.
Assuntos
Antígenos CD40/imunologia , Citotoxicidade Imunológica , Células Dendríticas/imunologia , Células Matadoras Naturais/imunologia , Apresentação de Antígeno , Antígenos CD40/genética , Técnicas de Transferência de Genes , Antígenos de Histocompatibilidade Classe I/imunologia , HumanosRESUMO
Virus-like particles (VLPs) composed of rotavirus VP2, VP6, and VP7 of G1 or G3 serotype specificity were produced in insect cells coinfected with recombinant baculoviruses expressing single rotavirus genes. The VLPs were purified and subsequently evaluated for immunogenicity and protection in the adult mouse model of rotavirus infection. Mice were vaccinated twice intramuscularly with G1 VLPs formulated with Quillaja saponaria (QS-21) or adsorbed to aluminium hydroxide (AlOH), or with G1 VLPs alone. G3 VLPs, G1 plus G3 VLPs, inactivated SA11 virions formulated with QS-21, or adjuvants were similarly inoculated as controls. Mice were examined for serum and fecal antibody responses by ELISA or microneutralization assays. Protective efficacy of the VLP vaccine formulations against oral challenge with the G3 murine ECwt rotavirus was assessed by comparing the antigen shed in stool of the VLP-vaccinated mice to that of the adjuvant-immunized mice. G1 VLPs in QS-21 induced significantly higher serum and intestinal antibody titers than G1 VLPs in AlOH or G1 VLPs alone. QS-21 also heightened serum and fecal antibody responses to G3 VLPs. These QS-21-augmented antibody responses were further characterized by equivalent IgG1 and IgG2a titers in sera, suggesting that G1 or G3 VLPs in QS-21 induced a balanced Th1/Th2 response. G1 VLPs in QS-21 induced partial protection (88%) against oral challenge with the heterotypic ECwt virus, whereas G3 VLPs in QS-21 induced complete protection (100%). In contrast, G1 VLPs when formulated with AlOH induced a predominant Th2 response and did not protect (1%) mice from virus challenge. Our results indicate that the type of adjuvant used clearly influences both antibody responses to rotavirus VLPs and the protective efficacy against rotavirus infections. These data have important implications for the development of parenteral vaccines to ameliorate rotavirus disease.