Probing human proteins for short encrypted antimicrobial peptides reveals Hs10, a peptide with selective activity for gram-negative bacteria.

BACKGROUND: Some cationic and amphiphilic α-helical segments of proteins adsorb to prokaryotic membranes when synthesized as individual polypeptide sequences, resulting in broad and potent antimicrobial activity. However, amphiphilicity, a determinant physicochemical property for peptide-membrane interactions, can also be observed in some ß-sheets. METHODS: The software Kamal was used to scan the human reference proteome for short (7-11 amino acid residues) cationic and amphiphilic protein segments with the characteristic periodicity of ß-sheets. Some of the uncovered peptides were chemically synthesized, and antimicrobial assays were conducted. Biophysical techniques were used to probe the molecular interaction of one peptide with phospholipid vesicles, lipopolysaccharides (LPS) and the bacterium Escherichia coli. RESULTS: Thousands of compatible segments were found in human proteins, five were synthesized, and three presented antimicrobial activity in the micromolar range. Hs10, a nonapeptide fragment of the Complement C3 protein, could inhibit only the growth of tested Gram-negative microorganisms, presenting also little cytotoxicity to human fibroblasts. Hs10 interacted with LPS while transitioning from an unstructured segment to a ß-sheet and increased the hydrodynamic radius of LPS particles. This peptide also promoted morphological alterations in E. coli cells. CONCLUSIONS: Data presented herein introduce yet another molecular template to probe proteins in search for encrypted membrane-active segments and demonstrates that, using this approach, short peptides with low cytotoxicity and high selectivity to prokaryotic cells might be obtained. GENERAL SIGNIFICANCE: This work widens the biotechnological potential of the human proteome as a source of antimicrobial peptides with application in human health.

Novel disintegrin-like peptides derived from an amphibian skin cDNA sequence of Hypsiboas punctatus.

Disintegrins comprise a family of small proteins that bind to and alter the physiological function of integrins, especially integrins that mediate platelet aggregation in blood. Here, we report a lysine-glycine-aspartic acid (KGD) disintegrin-like motif present in a 15-amino acid residue peptide identified in a cDNA library of the amphibian Hypsiboas punctatus skin. The original peptide sequence was used as a template from which five new analogs were designed, chemically synthesized by solid phase, and tested for disintegrin activity and tridimensional structural studies using NMR spectroscopy. The original amphibian peptide had no effect on integrin-mediated responses. Nevertheless, derived peptide analogs inhibited integrin-mediated platelet function, including platelet spreading on fibrinogen.

Brazilian Group of Gastrointestinal Tumours' consensus guidelines for the management of oesophageal cancer.

Oesophageal cancer is among the ten most common types of cancer worldwide. More than 80% of the cases and deaths related to the disease occur in developing countries. Local socio-economic, epidemiologic and healthcare particularities led us to create a Brazilian guideline for the management of oesophageal and oesophagogastric junction (OGJ) carcinomas. The Brazilian Group of Gastrointestinal Tumours invited 50 physicians with different backgrounds, including radiology, pathology, endoscopy, nuclear medicine, genetics, oncological surgery, radiotherapy and clinical oncology, to collaborate. This document was prepared based on an extensive review of topics related to heredity, diagnosis, staging, pathology, endoscopy, surgery, radiation, systemic therapy (including checkpoint inhibitors) and follow-up, which was followed by presentation, discussion and voting by the panel members. It provides updated evidence-based recommendations to guide clinical management of oesophageal and OGJ carcinomas in several scenarios and clinical settings.

Efficacy and Safety of Nivolumab Plus Ipilimumab versus Sunitinib in First-line Treatment of Patients with Advanced Sarcomatoid Renal Cell Carcinoma.

PURPOSE: Patients with advanced renal cell carcinoma with sarcomatoid features (sRCC) have poor prognoses and suboptimal outcomes with targeted therapy. This post hoc analysis of the phase III CheckMate 214 trial analyzed the efficacy of nivolumab plus ipilimumab (NIVO+IPI) versus sunitinib in patients with sRCC. PATIENTS AND METHODS: Patients with sRCC were identified via independent central pathology review of archival tumor tissue or histologic classification per local pathology report. Patients were randomized 1:1 to receive nivolumab (3 mg/kg) plus ipilimumab (1 mg/kg) every 3 weeks (four doses) then nivolumab 3 mg/kg every 2 weeks, or sunitinib 50 mg orally every day (4 weeks; 6-week cycles). Outcomes in patients with sRCC were not prespecified. Endpoints in patients with sRCC and International Metastatic Renal Cell Carcinoma Database Consortium intermediate/poor-risk disease included overall survival (OS), progression-free survival (PFS) per independent radiology review, and objective response rate (ORR) per RECIST v1.1. Safety outcomes used descriptive statistics. RESULTS: Of 1,096 randomized patients in CheckMate 214, 139 patients with sRCC and intermediate/poor-risk disease and six with favorable-risk disease were identified. With 42 months' minimum follow-up in patients with sRCC and intermediate/poor-risk disease, median OS [95% confidence interval (CI)] favored NIVO+IPI [not reached (NR) (25.2-not estimable [NE]); n = 74] versus sunitinib [14.2 months (9.3-22.9); n = 65; HR, 0.45 (95% CI, 0.3-0.7; P = 0.0004)]; PFS benefits with NIVO+IPI were similarly observed [median 26.5 vs. 5.1 months; HR, 0.54 (95% CI, 0.33-0.86; P = 0.0093)]. Confirmed ORR was 60.8% with NIVO+IPI versus 23.1% with sunitinib, with complete response rates of 18.9% versus 3.1%, respectively. No new safety signals emerged. CONCLUSIONS: NIVO+IPI showed unprecedented long-term survival, response, and complete response benefits versus sunitinib in previously untreated patients with sRCC and intermediate/poor-risk disease, supporting the use of first-line NIVO+IPI for this population.See related commentary by Hwang et al., p. 5.

Brazilian Group of Gastrointestinal Tumours' consensus guidelines for the management of gastric cancer.

Gastric cancer is among the ten most common types of cancer worldwide. Most cases and deaths related to the disease occur in developing countries. Local socio-economic, epidemiologic and healthcare particularities led us to create a Brazilian guideline for the management of gastric carcinomas. The Brazilian Group of Gastrointestinal Tumors (GTG) invited 50 physicians with different backgrounds, including radiology, pathology, endoscopy, nuclear medicine, genetics, oncological surgery, radiotherapy and clinical oncology, to collaborate. This document was prepared based on an extensive review of topics related to heredity, diagnosis, staging, pathology, endoscopy, surgery, radiation, systemic therapy and follow-up, which was followed by presentation, discussion, and voting by the panel members. It provides updated evidence-based recommendations to guide clinical management of gastric carcinomas in several scenarios and clinical settings.

Intragenic antimicrobial peptides (IAPs) from human proteins with potent antimicrobial and anti-inflammatory activity.

Following the treads of our previous works on the unveiling of bioactive peptides encrypted in plant proteins from diverse species, the present manuscript reports the occurrence of four proof-of-concept intragenic antimicrobial peptides in human proteins, named Hs IAPs. These IAPs were prospected using the software Kamal, synthesized by solid phase chemistry, and had their interactions with model phospholipid vesicles investigated by differential scanning calorimetry and circular dichroism. Their antimicrobial activity against bacteria, yeasts and filamentous fungi was determined, along with their cytotoxicity towards erythrocytes. Our data demonstrates that Hs IAPs are capable to bind model membranes while attaining α-helical structure, and to inhibit the growth of microorganisms at concentrations as low as 1µM. Hs02, a novel sixteen residue long internal peptide (KWAVRIIRKFIKGFIS-NH2) derived from the unconventional myosin 1h protein, was further investigated in its capacity to inhibit lipopolysaccharide-induced release of TNF-α in murine macrophages. Hs02 presented potent anti-inflammatory activity, inhibiting the release of TNF-α in LPS-primed cells at the lowest assayed concentration, 0.1 µM. A three-dimensional solution structure of Hs02 bound to DPC micelles was determined by Nuclear Magnetic Resonance. Our work exemplifies how the human genome can be mined for molecules with biotechnological potential in human health and demonstrates that IAPs are actual alternatives to antimicrobial peptides as pharmaceutical agents or in their many other putative applications.

Identification and characterization of phospholipases A2 from the skin secretion of Pithecopus azureus anuran.

The present work reports the isolation, characterization and the complete sequence of a phospholipase A2 (PLA2) present in the skin secretion of Pithecopus azureus. Among several peptides and small proteins previously described by our group from some species belonging to this amphibian genus (formerly named Phyllomedusa), a 15 kDa N-glycosylated protein showing PLA2 activity was purified, assayed, sequenced and named Pa-PLA2. The Pithecopus azureus skin phospholipase A2 polypeptide chain is composed by 125 amino acid residues linked by seven disulfide bonds and two N-glycosylated sites (N67 and N108). The Pa-PLA2 enzymatic activity was qualitatively evaluated and compared to classical viperid PLA2 showing that both, native and deglycosylated Pa-PLA2 forms, are catalytically functional. The tridimensional molecular model of Pa-PLA2 indicates that the observed glycan moieties are suggestively placed far from the active site of that enzyme and therefore having little or no significant role on the direct interaction of the Pa-PLA2 catalytic pocket and its substrates.

Rilotumumab plus epirubicin, cisplatin, and capecitabine as first-line therapy in advanced MET-positive gastric or gastro-oesophageal junction cancer (RILOMET-1): a randomised, double-blind, placebo-controlled, phase 3 trial.

BACKGROUND: Rilotumumab is a fully human monoclonal antibody that selectively targets the ligand of the MET receptor, hepatocyte growth factor (HGF). We aimed to assess the efficacy, safety, and pharmacokinetics of rilotumumab combined with epirubicin, cisplatin, and capecitabine, and to assess potential biomarkers, in patients with advanced MET-positive gastric or gastro-oesophageal junction adenocarcinoma. METHODS: This multicentre, randomised, double-blind, placebo-controlled, phase 3 study was done at 152 centres in 27 countries. We recruited adults (aged ≥18 years) with unresectable locally advanced or metastatic gastric or gastro-oesophageal junction adenocarcinoma, an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, MET-positive tumours (≥25% of tumour cells with membrane staining of ≥1+ staining intensity), and evaluable disease, who had not received previous systemic therapy. Eligible patients were randomly assigned (1:1) via a computerised voice response system to receive rilotumumab 15 mg/kg intravenously or placebo in combination with open-label chemotherapy (epirubicin 50 mg/m2 intravenously; cisplatin 60 mg/m2 intravenously; capecitabine 625 mg/m2 orally twice daily) in 21-day cycles for up to ten cycles. After completion of chemotherapy, patients continued to receive rilotumumab or placebo monotherapy until disease progression, intolerability, withdrawal of consent, or study termination. Randomisation was stratified by disease extent and ECOG performance status. Both patients and physicians were masked to study treatment assignment. The primary endpoint was overall survival, analysed by intention to treat. We report the final analysis. This study is registered with ClinicalTrials.gov, number NCT01697072. FINDINGS: Between Nov 7, 2012, and Nov 21, 2014, 609 patients were randomly assigned to rilotumumab plus epirubicin, cisplatin, and capecitabine (rilotumumab group; n=304) or placebo plus epirubicin, cisplatin, and capecitabine (placebo group; n=305). Study treatment was stopped early after an independent data monitoring committee found a higher number of deaths in the rilotumumab group than in the placebo group; all patients in the rilotumumab group subsequently discontinued all study treatment. Median follow-up was 7·7 months (IQR 3·6-12·0) for patients in the rilotumumab group and 9·4 months (5·3-13·1) for patients in the placebo group. Median overall survival was 8·8 months (95% CI 7·7-10·2) in the rilotumumab group compared with 10·7 months (9·6-12·4) in the placebo group (stratified hazard ratio 1·34, 95% CI 1·10-1·63; p=0·003). The most common grade 3 or worse adverse events in the rilotumumab and placebo groups were neutropenia (86 [29%] of 298 patients vs 97 [32%] of 299 patients), anaemia (37 [12%] vs 43 [14%]), and fatigue (30 [10%] vs 35 [12%]). The frequency of serious adverse events was similar in the rilotumumab and placebo groups (142 [48%] vs 149 [50%]). More deaths due to adverse events occurred in the rilotumumab group than the placebo group (42 [14%] vs 31 [10%]). In the rilotumumab group, 33 (11%) of 298 patients had fatal adverse events due to disease progression, and nine (3%) had fatal events not due to disease progression. In the placebo group, 23 (8%) of 299 patients had fatal adverse events due to disease progression, and eight (3%) had fatal events not due to disease progression. INTERPRETATION: Ligand-blocking inhibition of the MET pathway with rilotumumab is not effective in improving clinical outcomes in patients with MET-positive gastric or gastro-oesophageal adenocarcinoma. FUNDING: Amgen.

BRAZILIAN CONSENSUS FOR MULTIMODAL TREATMENT OF COLORECTAL LIVER METASTASES. MODULE 3: CONTROVERSIES AND UNRESECTABLE METASTASES.

In the last module of this consensus, controversial topics were discussed. Management of the disease after progression during first line chemotherapy was the first discussion. Next, the benefits of liver resection in the presence of extra-hepatic disease were debated, as soon as, the best sequence of treatment. Conversion chemotherapy in the presence of unresectable liver disease was also discussed in this module. Lastly, the approach to the unresectable disease was also discussed, focusing in the best chemotherapy regimens and hole of chemo-embolization.

Neste último módulo do consenso, abordou-se alguns temas controversos. O primeiro tópico discutido foi o manejo da doença após progressão na primeira linha de quimioterapia, com foco em se ainda haveria indicação cirúrgica neste cenário. A seguir, o painel debruçou-se sobre as situações de ressecção da doença hepática na presença de doença extra-hepática, assim como, qual a melhor sequência de tratamento. O tratamento de conversão para doença inicialmente irressecável também foi abordado neste módulo, incluindo as importantes definições de quando se pode esperar que a doença se torne ressecável e quais esquemas terapêuticos seriam mais efetivos à luz dos conhecimentos atuais sobre a biologia tumoral e taxas de resposta objetiva. Por último, o tratamento da doença não passível de ressecção foi discutida, focando-se nos melhores esquemas a serem empregados e seu sequenciamento, bem como o papel da quimioembolização no manejo destes pacientes.

Brazilian consensus for multimodal treatment of colorectal liver metastases. module 3: controversies and unresectable metastases / Consenso brasileiro de tratamento multidisciplinar de metástase hepática de origem colorretal módulo 3: controvérsias e metástases irressecáveis

ABSTRACT In the last module of this consensus, controversial topics were discussed. Management of the disease after progression during first line chemotherapy was the first discussion. Next, the benefits of liver resection in the presence of extra-hepatic disease were debated, as soon as, the best sequence of treatment. Conversion chemotherapy in the presence of unresectable liver disease was also discussed in this module. Lastly, the approach to the unresectable disease was also discussed, focusing in the best chemotherapy regimens and hole of chemo-embolization.

RESUMO Neste último módulo do consenso, abordou-se alguns temas controversos. O primeiro tópico discutido foi o manejo da doença após progressão na primeira linha de quimioterapia, com foco em se ainda haveria indicação cirúrgica neste cenário. A seguir, o painel debruçou-se sobre as situações de ressecção da doença hepática na presença de doença extra-hepática, assim como, qual a melhor sequência de tratamento. O tratamento de conversão para doença inicialmente irressecável também foi abordado neste módulo, incluindo as importantes definições de quando se pode esperar que a doença se torne ressecável e quais esquemas terapêuticos seriam mais efetivos à luz dos conhecimentos atuais sobre a biologia tumoral e taxas de resposta objetiva. Por último, o tratamento da doença não passível de ressecção foi discutida, focando-se nos melhores esquemas a serem empregados e seu sequenciamento, bem como o papel da quimioembolização no manejo destes pacientes.

NanoUPLC-MS(E) proteomic analysis of osteoclastogenesis downregulation by IL-4.

Bone resorption is an important factor in bone homeostasis and imbalance can cause several diseases. In osteoimmunology, IL-4 has been described as an important factor in promoting M2 macrophage profile. In order to shed some light on the effect of IL-4 on osteoclast precursors in the presence of RANKL, cytokines and nitric oxide (NO) production and the proteomic profile were analyzed. The presence of IL-4 in in vitro osteoclastogenesis provides production of TNF-α, IL-1α, IL-1ß, IL-10 and IL-12 at basal cell levels. Regarding NO production, IL-4 was sufficient to increase the basal NO levels. Proteomic analyses identified 877 global proteins. IL-4 in in vitro RANKL-mediated osteoclastogenesis leads to the expression of 118 proteins. The presence of rIL-4 in in vitro rRANKL-mediated-osteoclastogenesis downregulated this process. However, the proteomics findings in the osteoclastogenesis demonstrated a much greater effect on osteoclast precursor cells than on RANKL-differentiated osteoclasts. These results suggest that the main effect of IL-4 in pre-osteoclast cells leads to a M2 macrophage activation, and this probably contributed to a reduction in osteoclastogenesis when both stimuli were used. This study noticed that IL-4 plays an important regulatory role in bone homeostasis due to its suppressive potential of precursor osteoclast cells.

Gefitinib and celecoxib in advanced metastatic gastrointestinal tumors: a pilot feasibility study.

BACKGROUND: This pilot, open-label study examined the safety and tolerability (primary objective) and efficacy (secondary objective) of gefitinib, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, in combination with celecoxib, a cyclooxygenase-2 (COX-2) inhibitor, in patients with advanced or refractory gastrointestinal (GI) tumors of epithelial origin. METHODS: Patients were administered gefitinib (250 mg/day) plus celecoxib (400 mg twice daily). In the event of toxicity, dose interruptions were permitted and a single celecoxib dose reduction was allowed. RESULTS: Thirty patients (median age 60 years) with primary colorectal (25 patients), pancreatic (3 patients), esophageal (1 patient), or gall bladder (1 patient) tumors were recruited, 29 of whom had received prior chemotherapy. Adverse events (AEs) were generally mild and consisted mainly of acne, diarrhea, and nausea. Few severe AEs were noted. There were no withdrawals or deaths due to AEs. Dose reductions for celecoxib were reported for five patients, in three cases due to toxicity. Stable disease was confirmed in 12 patients (40%), with progressive disease in 18 patients (60%). CONCLUSIONS: After study completion, safety issues relating to the long-term use of COX-2 inhibitors have been raised. However, in this pilot study, the combination of gefitinib and celecoxib was generally well tolerated in patients with advanced GI cancer.

NanoUPLC-MSE proteomic data assessment of soybean seeds using the Uniprot database.

BACKGROUND: Recombinant DNA technology has been extensively employed to generate a variety of products from genetically modified organisms (GMOs) over the last decade, and the development of technologies capable of analyzing these products is crucial to understanding gene expression patterns. Liquid chromatography coupled with mass spectrometry is a powerful tool for analyzing protein contents and possible expression modifications in GMOs. Specifically, the NanoUPLC-MSE technique provides rapid protein analyses of complex mixtures with supported steps for high sample throughput, identification and quantization using low sample quantities with outstanding repeatability. Here, we present an assessment of the peptide and protein identification and quantification of soybean seed EMBRAPA BR16 cultivar contents using NanoUPLC-MSE and provide a comparison to the theoretical tryptic digestion of soybean sequences from Uniprot database. RESULTS: The NanoUPLC-MSE peptide analysis resulted in 3,400 identified peptides, 58% of which were identified to have no miscleavages. The experiment revealed that 13% of the peptides underwent in-source fragmentation, and 82% of the peptides were identified with a mass measurement accuracy of less than 5 ppm. More than 75% of the identified proteins have at least 10 matched peptides, 88% of the identified proteins have greater than 30% of coverage, and 87% of the identified proteins occur in all four replicates. 78% of the identified proteins correspond to all glycinin and beta-conglycinin chains.The theoretical Uniprot peptide database has 723,749 entries, and 548,336 peptides have molecular weights of greater than 500 Da. Seed proteins represent 0.86% of the protein database entries. At the peptide level, trypsin-digested seed proteins represent only 0.3% of the theoretical Uniprot peptide database. A total of 22% of all database peptides have a pI value of less than 5, and 25% of them have a pI value between 5 and 8. Based on the detection range of typical NanoUPLC-MSE experiments, i.e., 500 to 5000 Da, 64 proteins will not be identified. CONCLUSIONS: NanoUPLC-MSE experiments provide good protein coverage within a peptide error of 5 ppm and a wide MW detection range from 500 to 5000 Da. A second digestion enzyme should be used depending on the tissue or proteins to be analyzed. In the case of seed tissue, trypsin protein digestion results offer good databank coverage. The Uniprot database has many duplicate entries that may result in false protein homolog associations when using NanoUPLC-MSE analysis. The proteomic profile of the EMBRAPA BR-16 seed lacks certain described proteins relative to the profiles of transgenic soybeans reported in other works.

Detection and expression analysis of recombinant proteins in plant-derived complex mixtures using nanoUPLC-MS(E).

The use of mass spectrometry to identify recombinant proteins that are expressed in total soluble proteins (TSPs) from plant extracts is necessary to accelerate further processing steps. For example, the method consists of TSP sample preparation and trypsin digestion prior to the preliminary characterization using nanoUPLC-MS(E) analysis of the recombinant proteins that are expressed in TSP samples of transgenic soybean seeds. A TSP sample as small as 50 µg can be effectively analyzed. In this study, transgenic soybean seeds that expressed recombinant cancer testis antigen (CTAG) were used. The procedure covered 30% of the protein sequence and was quantified at 0.26 ng, which corresponded to 0.1% of the TSP sample. A comparative proteomic profile was generated by the comparison of a negative control and sample that showed a unique expression pattern of CTAG in a transgenic line. The experimental data from the TSP extraction, sample preparation and data analysis are discussed herein.

Cetuximab Plus irinotecan in pretreated metastatic colorectal cancer progressing on irinotecan: the LABEL study.

BACKGROUND: The aim of this multicenter phase II study was to demonstrate the activity of the epidermal growth factor receptor (EGFR)-targeting monoclonal antibody cetuximab combined with irinotecan in the treatment of Latin American patients with EGFR-expressing metastatic colorectal cancer (mCRC) in whom previous treatment with an irinotecan-containing regimen had failed. PATIENTS AND METHODS: Patients received cetuximab, as a 400 mg/m2 initial infusion followed by 250 mg/m2 weekly, plus the same irinotecan regimen that had previously failed, until the occurrence of disease progression or unacceptable toxicity. The primary endpoint was response. Secondary endpoints included progression-free survival (PFS), duration of response, overall survival (OS), and safety. RESULTS: Seventy-nine patients received treatment. One patient had a complete response, 20 had partial responses, and disease was stabilized in 23 patients, giving an overall response rate of 27% and a disease control rate of 56%. The median duration of response was 23.9 weeks. Median PFS was 17.4 weeks, median OS was 9.2 months, and the 12-month OS rate was 38%. The most common adverse events according to System Organ Class were skin and subcutaneous tissue disorders (91% of the patients). Grade 3/4 adverse events occurred in 45 patients (57%), with the most common being diarrhea (20%), neutropenia (11%), and rash (6%). Seven patients (9%) had grade 3/4 acne-like skin rash. No grade 3/4 infusion-related reactions were reported. CONCLUSION: Cetuximab in combination with irinotecan is active and tolerable in Latin American patients with mCRC progressing on irinotecan, with a safety profile similar to that described in European studies.

Novel insights on the mechanism of action of alpha-amylase inhibitors from the plant defensin family.

Plant defensins are small cysteine-rich proteins commonly synthesized in plants, encoded by large multigene families. Most plant defensins that have been characterized to date show potent antifungal and/or bactericidal activities. This report describes VuD1, an unusual defensin that is able to inhibit insect-pest alpha-amylases. VuD1 was cloned from cowpea (Vigna unguiculata) seeds and expressed in a heterologous system. Inhibitory enzyme assays showed that VuD1 efficiently inhibits alpha-amylases from the weevils Acanthoscelides obtectus and Zabrotes subfasciatus, caused low inhibition toward mammalian enzymes and was unable to inhibit the alpha-amylases from Callosobruchus maculatus and Aspergillus fumigatus. To shed some light over the mechanism of action of VuD1, molecular modeling analyses were performed, revealing that the N-terminus of the molecule is responsible for binding with the active site of weevil enzymes. Moreover, models of VuD1 and mammalian enzymes were also generated to elucidate the specificity mechanisms. The data presented herein suggests that this defensin has potential application in the development of transgenic plants for insect pest control.

Identification of a cowpea gamma-thionin with bactericidal activity.

Antimicrobial peptides are an abundant group of proteinaceous compounds widely produced in the plant kingdom. Among them, the gamma-thionin family, also known as plant defensins, represents one typical family and comprises low molecular mass cysteine-rich proteins, usually cationic and distributed in different plant tissues. Here, we report the purification and characterization of a novel gamma-thionin from cowpea seeds (Vigna unguiculata), named Cp-thionin II, with bactericidal activity against Gram-positive and Gram-negative bacteria. Once the primary structure was elucidated, molecular modelling experiments were used to investigate the multimerization and mechanism of action of plant gamma-thionins. Furthermore, Cp-thionin II was also localized in different tissues in cowpea seedlings during germination in contrasting conditions, to better understand the plant protection processes. The use of plant defensins in the construction of transgenic plants and also in the production of novel drugs with activity against human pathogens is discussed.

Phase II multicenter trial of docetaxel, epirubicin, and 5-fluorouracil (DEF) in the treatment of advanced gastric cancer: a novel, safe, and active regimen.

BACKGROUND: This study evaluated the efficacy and safety of docetaxel, epirubicin, and 5-fluorouracil (5-FU) [DEF] as treatment for locally advanced unresectable or metastatic gastric cancer. METHODS: Thirty-seven patients participated in the study (median age, 56 years; range, 22-73 years); Eastern Cooperative Oncology Group performance status [PS], 0-2). Docetaxel 75 mg/m2 IV (day 1), 5-FU 500 mg/m2 IV (days 1-3), and epirubicin 50 mg/m2 IV (day 1) were administered every 3 weeks for six cycles. RESULTS: In total, 20/37 patients (54%) completed six treatment cycles. Thirteen patients (35%; 95% confidence intervals [CI], 20% to 51%) had an objective response; 1 patient (3%) achieved a complete response and 12 patients (32%) achieved partial responses. Stable disease was observed in 7 patients (19%) and progressive disease in 5 patients (14%). Twelve patients (32%) were unevaluable. Clinical benefit (based on PS, weight gain, and analgesic consumption) was observed in 11 patients (30%). Median follow-up was 41 months (range, 26-53 months), median time to progression was 6.6 months (range, 0.5-29.2 months), median overall survival was 10.7 months (range, 7.0-14.6 months), and 1-year survival was 40%. The regimen was well tolerated. Grade 3-4 febrile neutropenia occurred in 8 patients (22%; 6% of cycles) and grade 3-4 neutropenia in 1 patient (1% of cycles). The most frequent grade 3-4 toxicities were alopecia (11% of cycles), diarrhea (4% of cycles) and vomiting (2% of cycles); grade 1-2 asthenia and fatigue occurred in 43% of cycles. CONCLUSION: DEF is effective in the treatment of advanced gastric cancer, and has a good safety profile.

Phase II trial of the use of gemcitabine and 5-fluorouracil in the treatment of advanced pancreatic and biliary tract cancer.

In this phase II trial, we used the combination of gemcitabine and 5-fluorouracil (5-FU) to treat 26 patients: 17 (65%) with advanced pancreatic adenocarcinoma and 9 (35%) with advanced biliary tract adenocarcinoma (10 locally advanced and 16 metastatic); 15 (57.7%) male and 11 (42.3%) female; median age 58 (range, 39-68); median performance status 2 (range, 1-3). A total of 102 cycles were administered (median, 4 per patient). There were 8 objective responses, plus 1 complete response not confirmed by second-look laparotomy, thus the overall objective response rate was 30.7% (95% CI 12%-47%). Among the patients with biliary tract carcinoma, 33% (3/9) had PR. Six (23%) patients had stable disease (SD). All 8 responders and 3 of the patients with SD experienced clinical benefit (42%). The median overall survival was 9 months (range, 6-38), and the 1-year survival rate was 30%. The regimen was very well tolerated. One patient developed reversible World Health Organization grade IV febrile neutropenia. We observed grade III neutropenia in 11 (11%) cycles; grade III thrombocytopenia in 7 (7%) cycles; grade III mucositis in 7 (7%) cycles; and grade III diarrhea in 10 (10%) cycles. Asthenia grades I and II occurred in 30% of cycles and flulike syndrome grade II in 11 (11%) cycles. The combination of gemcitabine and 5-FU in patients with advanced pancreatic or biliary tract cancer produces promising activity and tolerability with the added potential for clinical benefit, and thus warrants further investigation.