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2.
J Orthop Sports Phys Ther ; 53(9): 498­509, 2023 09.
Article in English | MEDLINE | ID: mdl-37555664

ABSTRACT

BACKGROUND: Sport-specific training is an integral component of returning to sport following injury. Frameworks designed to guide sport-specific rehabilitation need to integrate and adapt to the specific context of elite sport. The control-chaos continuum (CCC) is a flexible framework originally designed for on-pitch rehabilitation in elite football (soccer). The concepts underpinning the CCC transfer to other elite sport rehabilitation environments. CLINICAL QUESTION: How can practitioners and clinicians transfer the CCC to elite basketball, to support planning and return to sport? On-court rehabilitation is a critical sport-specific rehabilitation component of return to sport, yet there are no frameworks to guide practitioners when planning and delivering on-court rehabilitation. KEY RESULTS: Based on our experience working in the National Basketball Association, we report how the CCC framework can apply to elite basketball. We focus on the design and delivery of progressive training in the presence of injury in this basketball-specific edition of the CCC. Given the challenges when quantifying "load" in basketball, we encourage practitioners and clinicians to consider the qualitative aspects of performance such as skill, sport-specific movement, contact, and decision making. CLINICAL APPLICATION: The 5-phase framework describes training progression from high control, a return to on-court running, to high chaos, a return to "live" unrestricted basketball. The model can be adapted to both short- and long-term injuries based on injury and progression criteria. Strength and power "diagnostics" can be strategically implemented to enhance decision making throughout the return to sport continuum. J Orthop Sports Phys Ther 2023;53(9):1-12. Epub: 9 August 2023. doi:10.2519/jospt.2023.11981.


Subject(s)
Athletic Injuries , Basketball , Running , Soccer , Humans , Basketball/injuries , Athletic Injuries/rehabilitation , Soccer/injuries , Return to Sport
4.
Pediatr Exerc Sci ; 34(2): 76-83, 2022 05 01.
Article in English | MEDLINE | ID: mdl-34894627

ABSTRACT

PURPOSE: To assess the efficacy of a supervised in-school combined resistance and aerobic training program in adolescent girls and investigate whether responses differ according to birthweight. METHODS: Participants (girls aged 13-17 y) were randomized either to an intervention replacing physical education (PE) classes with 2 × 60-minute training sessions per week (n = 58) or to a control group that continued to attend 2 × 60 minutes per week of curriculum PE (n = 41). We measured muscular fitness (handgrip, standing long jump, and sit-ups), cardiorespiratory fitness (20-m shuttle run), skinfolds, and lean body mass preintervention and postintervention and determined effect size (Hedge's g) differences between changes in these measures. We also compared changes within lower (<3000 g) and normal birthweight intervention and PE control subgroups. RESULTS: The intervention group showed greater improvements in all the fitness measures and lean body mass (g = 0.22-0.48) and lower skinfold increases (g = 0.41) than PE controls. Within the intervention group, improvements in all fitness measures were larger in lower birthweight (g = 0.53-0.94) than in normal birthweight girls (g = 0.02-0.39). CONCLUSION: Replacing curriculum PE with supervised training improved muscular and cardiorespiratory fitness and body composition outcomes in adolescent females. Our findings suggest an enhanced adaptive response to training in participants with lower birthweight which warrants further investigation.


Subject(s)
Cardiorespiratory Fitness , Resistance Training , Adolescent , Birth Weight , Female , Hand Strength , Humans , Physical Fitness/physiology , Schools
5.
Cancer Immunol Res ; 9(12): 1451-1464, 2021 12.
Article in English | MEDLINE | ID: mdl-34635485

ABSTRACT

Immune-checkpoint blockade has revolutionized cancer treatment. However, most patients do not respond to single-agent therapy. Combining checkpoint inhibitors with other immune-stimulating agents increases both efficacy and toxicity due to systemic T-cell activation. Protease-activatable antibody prodrugs, known as Probody therapeutics (Pb-Tx), localize antibody activity by attenuating capacity to bind antigen until protease activation in the tumor microenvironment. Herein, we show that systemic administration of anti-programmed cell death ligand 1 (anti-PD-L1) and anti-programmed cell death protein 1 (anti-PD-1) Pb-Tx to tumor-bearing mice elicited antitumor activity similar to that of traditional PD-1/PD-L1-targeted antibodies. Pb-Tx exhibited reduced systemic activity and an improved nonclinical safety profile, with markedly reduced target occupancy on peripheral T cells and reduced incidence of early-onset autoimmune diabetes in nonobese diabetic mice. Our results confirm that localized PD-1/PD-L1 inhibition by Pb-Tx can elicit robust antitumor immunity and minimize systemic immune-mediated toxicity. These data provide further preclinical rationale to support the ongoing development of the anti-PD-L1 Pb-Tx CX-072, which is currently in clinical trials.


Subject(s)
Antibodies, Monoclonal/therapeutic use , B7-H1 Antigen/therapeutic use , Immunotherapy/methods , Amino Acid Sequence , Animals , Antibodies, Monoclonal/pharmacology , B7-H1 Antigen/pharmacology , Cell Line, Tumor , Disease Models, Animal , Humans , Mice , Tumor Microenvironment
6.
PLoS One ; 16(4): e0248110, 2021.
Article in English | MEDLINE | ID: mdl-33878107

ABSTRACT

The aim of this study was to evaluate the impact on muscle strength, aerobic fitness and body composition, of replacing the physical education (PE) class of Colombian adolescents with resistance or aerobic training. 120 tanner stage 3 adolescents attending a state school were randomized to resistance training, aerobic training, or a control group who continued to attend a weekly 2- hour PE class for 16 weeks. The resistance training and aerobic training groups participated in twice weekly supervised after-school exercise sessions of < 1 hour instead of their PE class. Sum of skinfolds, lean body mass (bioelectrical impedance analysis), muscular strength (6 repetition maximum (RM)) bench press, lateral pulldown and leg press) and estimated cardiorespiratory fitness (multistage 20 meter shuttle run) were assessed at pre and post intervention. Complete data were available for n = 40 of the resistance training group, n = 40 of the aerobic training group and n = 30 PE (controls). Resistance training attenuated increases in sum of skinfolds compared with controls (d = 0.27, [0.09-0.36]). We found no significant effect on lean body mass. Resistance training produced a positive effect on muscle strength compared with both controls (d = 0.66 [.49-.86]) and aerobic training (d = 0.55[0.28-0.67]). There was a positive effect of resistance training on cardiorespiratory fitness compared with controls (d = 0.04 [-0.10-0.12]) but not compared with aerobic training (d = 0.24 [0.10-0.36]). Replacing a 2-hour PE class with two 1 hour resistance training sessions attenuated gains in subcutaneous adiposity, and enhanced muscle strength and aerobic fitness development in Colombian youth, based on a median attendance of approximately 1 session a week. Further research to assess whether adequate stimuli for the development of muscular fitness exists within current physical education provision is warranted.


Subject(s)
Body Composition/physiology , Exercise/physiology , Physical Fitness/physiology , Adolescent , Cardiorespiratory Fitness , Colombia/epidemiology , Exercise Test/methods , Exercise Therapy , Female , Humans , Male , Muscle Strength/physiology , Muscle, Skeletal/physiology , Obesity/metabolism , Obesity/physiopathology , Resistance Training/methods , Weight Lifting
7.
Rev. Fac. Nac. Salud Pública ; 38(2): e337834, May-Aug. 2020. tab
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1115183

ABSTRACT

Resumen Objetivo: Describir la percepción que tienen adolescentes escolarizados entre 12 y 16 años, en Piedecuesta (Santander), en 2016, sobre los facilitadores y las barreras que influyen en la práctica de la actividad física. Metodología: Análisis cualitativo desde un enfoque fenomenológico, con la participación de 20 adolescentes escolarizados que, mediante entrevistas semiestructuradas y un grupo focal, conversaron sobre la práctica, los beneficios, los entornos y la influencia y la compañía en relación con la actividad física, para identificar barreras y facilitadores. Resultados: La práctica de la actividad física se limitaba a las clases de educación física en la mayoría de los casos. El compañero principal en la práctica extracurricular era el padre del mismo sexo. La actividad física representaba una oportunidad para el disfrute, mejorar la salud física y mental, así como la contextura corporal, y para romper con la rutina diaria. La falta de tiempo por compromisos académicos fue la razón principal para no realizar actividad física. Los lugares públicos no siempre estaban disponibles, a menudo no se consideraban seguros. En la escuela, el espacio y las instalaciones eran inadecuados, y el uso estaba restringido. Conclusiones: La escuela es un punto de convergencia importante para la práctica de la actividad física, lo que sugiere la necesidad de fortalecer el plan de estudios al respecto; este entorno es un facilitador potencial para aumentar el nivel de actividad física en adolescentes. También se percibe como barrera, dado que la práctica interfiere con las actividades académicas. Las mejoras en la seguridad y el atractivo estético en el entorno comunitario se visibilizan como un facilitador para promover la actividad física.


Abstract Objective: Describe the perception of adolescents aged between 12 and 16 years, in Piedecuesta (Santander), in 2016, about the facilitators and barriers that influence physical activity. Methodology: Qualitative analysis from a phenomenological approach, with the participation of 20 adolescents who talked about the practice, benefits, environments, influence and company in connection with physical activity , to identify barriers and facilitators, through semi-structured interviews and a focus group. Results: Physical activity was limited to physical education classes in most cases. The main companion in extracurricular physical activity was the parent of the same sex. Physical activity represented an opportunity for enjoyment, improvement of physical and mental health, as well as body composition, and to have a break in their daily routine. Lack of time due to academic commitments was the main reason for not doing physical activity. Public places were not always available and they were often not considered to be safe. Space and facilities at school were inadequate, and their use was restricted.. Conclusions: The school is an important point of convergence for doing physical activity, suggesting the need to strengthen the curriculum in this respect; this environment is a potential facilitator to increasing the level of physical activity in adolescents. It can also be seen as a barrier, given that the practice interferes with academic activities. Improvements in safety and aesthetic appeal in the surrounding community are seen as a facilitator to promoting physical activity.


Resumo Objetivo: Descrever a percepção que os adolescentes entre 12 e 17 anos de Piedecuesta em Santander, tiveram em 2016 sobre os facilitadores e as barreiras que influenciaram na prática da atividade física. Metodologia: Análise qualitativa partindo de um foco fenomenológico, com a participação de 20 adolescentes em idade escolar que, através de entrevistas semiestruturadas e um grupo focal, conversaram sobre a prática, os benefícios, os entornos, a influência e o acompanhamento relacionados com a atividade física, para identificar barreiras e facilitadores. Resultados: Na maioria dos casos, a prática da atividade física limitava-se às aulas de educação física. O companheiro principal na prática extracurricular era o genitor ou genitora do mesmo sexo. A atividade física representava uma oportunidade para disfrutar, melhorar a saúde física e mental, além da estrutura corporal e para sair da rotina diária. A falta de tempo devido às responsabilidades escolares foi a principal razão para não realizarem atividade física. Os lugares públicos nem sempre estavam disponíveis e geralmente não são considerados seguros. Na escola, o espaço e as instalações eram inadequados e o uso estava restrito. Conclusões: A escola é um importante ponto de convergência para a prática da atividade física, o que determina a necessidade de fortalecer o currículo relacionado; esse ambiente é um facilitador potencial para aumentar o nível de atividade física nos adolescentes. Também se percebe como barreira, já que a prática interfere com as atividades escolares. As melhorias na segurança e um espaço comunitário mais atraente do ponto de vista estético são determinantes como facilitadores para a promoção da atividade física.

9.
ACS Med Chem Lett ; 10(12): 1674-1679, 2019 Dec 12.
Article in English | MEDLINE | ID: mdl-31857845

ABSTRACT

Targeted antimitotic agents are a promising class of anticancer therapies. Herein, we describe the development of a potent and selective antimitotic Eg5 inhibitor based antibody-drug conjugate (ADC). Preliminary studies were performed using proprietary Eg5 inhibitors which were conjugated onto a HER2-targeting antibody using maleimido caproyl valine-citrulline para-amino benzocarbamate, or MC-VC-PABC cleavable linker. However, the resulting ADCs lacked antigen-specificity in vivo, probably from premature release of the payload. Second-generation ADCs were then developed, using noncleavable linkers, and the resulting conjugates (ADC-4 and ADC-10) led to in vivo efficacy in an HER-2 expressing (SK-OV-3ip) mouse xenograft model while ADC-11 led to in vivo efficacy in an anti-c-KIT (NCI-H526) mouse xenograft model in a target-dependent manner.

13.
Int J Cancer ; 143(6): 1483-1493, 2018 09 15.
Article in English | MEDLINE | ID: mdl-29665011

ABSTRACT

Tumor-associated macrophages can promote growth of cancers. In neuroblastoma, tumor-associated macrophages have greater frequency in metastatic versus loco-regional tumors, and higher expression of genes associated with macrophages helps to predict poor prognosis in the 60% of high-risk patients who have MYCN-non-amplified disease. The contribution of cytotoxic T-lymphocytes to anti-neuroblastoma immune responses may be limited by low MHC class I expression and low exonic mutation frequency. Therefore, we modelled human neuroblastoma in T-cell deficient mice to examine whether depletion of monocytes/macrophages from the neuroblastoma microenvironment by blockade of CSF-1R can improve the response to chemotherapy. In vitro, CSF-1 was released by neuroblastoma cells, and topotecan increased this release. In vivo, neuroblastomas formed by subcutaneous co-injection of human neuroblastoma cells and human monocytes into immunodeficient NOD/SCID mice had fewer human CD14+ and CD163+ cells and mouse F4/80+ cells after CSF-1R blockade. In subcutaneous or intra-renal models in immunodeficient NSG or NOD/SCID mice, CSF-1R blockade alone did not affect tumor growth or mouse survival. However, when combined with cyclophosphamide plus topotecan, the CSF-1R inhibitor BLZ945, either without or with anti-human and anti-mouse CSF-1 mAbs, inhibited neuroblastoma growth and synergistically improved mouse survival. These findings indicate that depletion of tumor-associated macrophages from neuroblastomas can be associated with increased chemotherapeutic efficacy without requiring a contribution from T-lymphocytes, suggesting the possibility that combination of CSF-1R blockade with chemotherapy might be effective in patients who have limited anti-tumor T-cell responses.


Subject(s)
Antineoplastic Agents/pharmacology , Drug Resistance, Neoplasm , Macrophages/drug effects , Monocytes/drug effects , Neuroblastoma/drug therapy , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/antagonists & inhibitors , Animals , Apoptosis , Benzothiazoles/pharmacology , Biomarkers, Tumor/metabolism , Cell Proliferation , Cells, Cultured , Disease Models, Animal , Humans , Macrophages/immunology , Macrophages/pathology , Mice , Mice, Inbred NOD , Mice, SCID , Monocytes/immunology , Monocytes/pathology , Neuroblastoma/metabolism , Neuroblastoma/pathology , Picolinic Acids/pharmacology , T-Lymphocytes, Cytotoxic/drug effects , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Cytotoxic/pathology , Xenograft Model Antitumor Assays
14.
J Pediatr ; 185: 81-87.e2, 2017 06.
Article in English | MEDLINE | ID: mdl-28161198

ABSTRACT

OBJECTIVE: To determine the associations between socioeconomic status (SES) and physical fitness in a sample of Colombian youth. STUDY DESIGN: Prueba SER is cross-sectional survey of schoolchildren in Bogota, Colombia. Mass, stature, muscular fitness (standing long-jump, handgrip), and cardiorespiratory fitness (20-m shuttle run) were measured in 52?187 schoolchildren 14-16 years of age. Area-level SES was categorized from 1 (very low) to 4 (high) and parent-reported family income was categorized as low, middle, or high. RESULTS: Converting measures into z scores showed stature, muscular, and cardiorespiratory fitness were significantly (z?=?0.3-0.7) below European values. Children in the mid- and high SES groups jumped significantly further than groups with very low SES. Differences were independent of sex but became nonsignificant when adjusted for anthropometric differences. Participants in the mid-SES and high-SES groups had better handgrip scores when adjusted for body dimension. There were, however, no significant between-group differences in cardiorespiratory fitness, which was strongly clustered by school and significantly greater in students from private schools. CONCLUSIONS: Area-level SES is associated with measures of muscular fitness in Colombian schoolchildren. These associations were largely explained by the large differences in body dimensions observed between SES groups. When area-level SES is considered, there was no evidence that family income influenced fitness. The clustering of outcomes reaffirms the potential importance of schools and area-level factors in promoting fitness through opportunities for physical activity. Interventions implemented in schools, can improve academic attainment; a factor likely to be important in promoting the social mobility of children from poorer families.


Subject(s)
Cardiorespiratory Fitness , Muscle Strength , Social Class , Adolescent , Body Height , Body Mass Index , Colombia , Cross-Sectional Studies , Female , Humans , Income , Male , Private Sector , Public Sector , Schools
15.
Am J Hum Biol ; 29(1)2017 Jan.
Article in English | MEDLINE | ID: mdl-27427286

ABSTRACT

OBJECTIVE: To determine sociodemographic factors associated with handgrip (HG) strength in a representative sample of children and adolescents from a middle income country. METHODS: We evaluated youth between the ages of 8 and 17 from a representative sample of individuals from the Department of Santander, Colombia. Anthropometric measures, HG strength, and self-reported physical activity were assessed, and parents/guardians completed sociodemographic questionnairres. Multinomial logistic regression models were used to estimate the association between sociodemographic and anthropometric characteristics and tertiles of relative HG strength. We also produced centile data for raw HG strength using quantile regression. RESULTS: 1,691 young people were evaluated. HG strength increased with age, and was higher in males than females in all age groups. Lower HG strength was associated with indicators of higher socioeconomic status, such as living in an urban area, residence in higher social strata neighborhoods, parent/guardian with secondary education or higher, higher household income, and membership in health insurance schemes. In addition, low HG strength was associated with lower physical activity levels and higher waist-to-hip ratio. In a fully adjusted regression model, all factors remained significant except for health insurance, household income, and physical activity level. CONCLUSIONS: While age and gender specific HG strength values were substantially lower than contemporary data from high income countries, we found that within this middle income population indicators of higher socioeconomic status were associated with lower HG strength. This analysis also suggests that in countries undergoing rapid nutrition transition, improvements in socioeconomic conditions may be accompanied by reduction in muscle strength.


Subject(s)
Anthropometry , Hand Strength , Socioeconomic Factors , Adolescent , Age Factors , Child , Colombia , Exercise , Female , Humans , Logistic Models , Male , Waist-Hip Ratio
16.
Med Hypotheses ; 90: 32-40, 2016 May.
Article in English | MEDLINE | ID: mdl-27063082

ABSTRACT

Myopia is a multifactorial visual refraction disease, in which the light rays from distant objects are focused in front of retina, causing blurry vision. Myopic eyes are characterized by an increased corneal curvature and/or ocular axial length. The prevalence of myopia has increased in recent decades, a trend that cannot be attributed exclusively to genetic factors. Low and middle income countries have a higher burden of refractive error, which we propose could be a consequence of a shorter exposure time to a westernized lifestyle, a phenomenon that may also explain the rapid increase in cardiometabolic diseases, such as diabetes, among those populations. We suggest that interactions between genetic, epigenetic and a rapidly changing environment are also involved in myopia onset and progression. Furthermore, we discuss several possible mechanisms by which insulin resistance may promote abnormal ocular growth and myopia to support the hypothesis that insulin resistance and hyperinsulinemia are involved in its pathogenesis, providing a link between trends in myopia and those of cardiometabolic diseases. There is evidence that insulin have direct ocular growth promoting effects as well an indirect effect via the induction of insulin-like growth factors leading to decreases insulin-like growth factor-binding protein, also implicated in ocular growth.


Subject(s)
Insulin Resistance/physiology , Myopia/etiology , Animals , Demography , Developing Countries , Diabetes Complications/physiopathology , Diet, Western/adverse effects , Gene-Environment Interaction , Global Health , Humans , Hyperglycemia/complications , Hyperglycemia/physiopathology , Hyperinsulinism/complications , Hyperinsulinism/physiopathology , Insulin-Like Growth Factor Binding Proteins/physiology , Life Style , Models, Biological , Myopia/chemically induced , Myopia/epidemiology , Obesity/complications , Obesity/physiopathology , Prevalence , Risk Factors , Social Change , Somatomedins/physiology , Somatomedins/toxicity
17.
BMC Pediatr ; 16: 31, 2016 Mar 08.
Article in English | MEDLINE | ID: mdl-26956385

ABSTRACT

BACKGROUND: The current study aims to evaluate the association between neck circumference (NC) and several cardio-metabolic risk factors, to compare it with well-established anthropometric indices, and to determine the cut-off point value of NC for predicting children at increased risk of metabolic syndrome, insulin resistance and low-grade systemic inflammation. METHODS: A total of 669 school children, aged 8-14, were recruited. Demographic, clinical, anthropometric and biochemical data from all patients were collected. Correlations between cardio-metabolic risk factors and NC and other anthropometric variables were evaluated using the Spearman's correlation coefficient. Multiple linear regression analysis was applied to further examine these associations. We then determined by receiver operating characteristic (ROC) analyses the optimal cut-off for NC for identifying children with elevated cardio-metabolic risk. RESULTS: NC was positively associated with fasting plasma glucose and triglycerides (p = 0.001 for all), and systolic and diastolic blood pressure, C-reactive protein, insulin and HOMA-IR (p < 0.001 for all), and negatively with HDL-C (p = 0.001). Whereas, other anthropometric indices were associated with fewer risk factors. CONCLUSIONS: NC could be used as clinically relevant and easy to implement indicator of cardio-metabolic risk in children.


Subject(s)
Inflammation/diagnosis , Metabolic Syndrome/diagnosis , Neck/anatomy & histology , Adolescent , Biomarkers/blood , Blood Glucose/metabolism , C-Reactive Protein/metabolism , Child , Colombia , Cross-Sectional Studies , Female , Humans , Inflammation/blood , Inflammation/etiology , Insulin/blood , Insulin Resistance , Linear Models , Male , Metabolic Syndrome/blood , Metabolic Syndrome/etiology , ROC Curve , Risk Factors , Triglycerides/blood
18.
J Sports Sci ; 34(14): 1363-70, 2016 Jul.
Article in English | MEDLINE | ID: mdl-26930226

ABSTRACT

We analysed the time course of recovery of creatine kinase (CK) and countermovement jump (CMJ) parameters after a football match, and correlations between changes in these variables and match time-motion parameters (GPS-accelerometry) in 15 U-19 elite male players. Plasma CK and CMJ height (CMJH), average concentric force (CMJCON) and average eccentric force (CMJECC) were assessed 2 h before and 30 min, 24 h and 48 h post-match. There were substantially higher CK levels 30 min, 24 h and 48 h (ES: 0.43, 0.62, 0.40, respectively), post-match. CMJECC (ES: -0.38), CMJH (ES: -0.35) decreased 30 min post, CMJCON (ES: -0.35), CMJECC (ES: -0.35) and CMJH (ES: -1.35) decreased 24 h post, and CMJCON (ES: -0.41) and CMJH (ES: -0.53) decreased 48 h post. We found correlations between distance covered at velocities ≤21 km · h(-1) and changes in CK at 24 h (r = 0.56) and at 48 h (r = 0.54) and correlations between CK and distance covered >14 km · h(-1) (r = 0.50), accelerations (r = 0.48), and decelerations (r = 0.58) at 48 h. Changes in CMJCON 30 min and 24 h post (both r = -0.68) correlated with impacts >7.1·G. Decelerations >2 m · s(-)(2) correlated with changes CMJCON (r = -0.49) at 48 h and CMJECC (r = -0.47) at 30 min. Our results suggest that match GPS-accelerometry parameters may predict muscle damage and changes in components of neuromuscular performance immediately and 24-48 h post-match.


Subject(s)
Athletic Performance/physiology , Competitive Behavior/physiology , Muscle, Skeletal/injuries , Soccer/injuries , Soccer/physiology , Adolescent , Creatine Kinase/blood , Humans , Male , Muscle, Skeletal/enzymology , Plyometric Exercise , Time Factors , Time and Motion Studies
19.
Bioconjug Chem ; 26(12): 2554-62, 2015 Dec 16.
Article in English | MEDLINE | ID: mdl-26588668

ABSTRACT

Post-translational modification catalyzed by phosphopantetheinyl transferases (PPTases) has previously been used to site-specifically label proteins with structurally diverse molecules. PPTase catalysis results in covalent modification of a serine residue in acyl/peptidyl carrier proteins and their surrogate substrates which are typically fused to the N- or C-terminus. To test the utility of PPTases for preparing antibody-drug conjugates (ADCs), we inserted 11 and 12-mer PPTase substrate sequences at 110 constant region loop positions of trastuzumab. Using Sfp-PPTase, 63 sites could be efficiently labeled with an auristatin toxin, resulting in 95 homogeneous ADCs. ADCs labeled in the CH1 domain displayed in general excellent pharmacokinetic profiles and negligible drug loss. A subset of CH2 domain conjugates underwent rapid clearance in mouse pharmacokinetic studies. Rapid clearance correlated with lower thermal stability of the particular antibodies. Independent of conjugation site, almost all ADCs exhibited subnanomolar in vitro cytotoxicity against HER2-positive cell lines. One selected ADC was shown to induce tumor regression in a xenograft model at a single dose of 3 mg/kg, demonstrating that PPTase-mediated conjugation is suitable for the production of highly efficacious and homogeneous ADCs.


Subject(s)
Aminobenzoates/metabolism , Antineoplastic Agents/metabolism , Bacterial Proteins/metabolism , Immunoconjugates/metabolism , Neoplasms/drug therapy , Oligopeptides/metabolism , Transferases (Other Substituted Phosphate Groups)/metabolism , Trastuzumab/metabolism , Aminobenzoates/chemistry , Aminobenzoates/therapeutic use , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/therapeutic use , Humans , Immunoconjugates/chemistry , Immunoconjugates/therapeutic use , Mice , Mice, Nude , Neoplasms/metabolism , Oligopeptides/chemistry , Oligopeptides/therapeutic use , Peptides/chemistry , Peptides/metabolism , Substrate Specificity , Trastuzumab/chemistry , Trastuzumab/therapeutic use
20.
ACS Med Chem Lett ; 6(7): 776-81, 2015 Jul 09.
Article in English | MEDLINE | ID: mdl-26191365

ABSTRACT

The discovery of inhibitors targeting novel allosteric kinase sites is very challenging. Such compounds, however, once identified could offer exquisite levels of selectivity across the kinome. Herein we report our structure-based optimization strategy of a dibenzodiazepine hit 1, discovered in a fragment-based screen, yielding highly potent and selective inhibitors of PAK1 such as 2 and 3. Compound 2 was cocrystallized with PAK1 to confirm binding to an allosteric site and to reveal novel key interactions. Compound 3 modulated PAK1 at the cellular level and due to its selectivity enabled valuable research to interrogate biological functions of the PAK1 kinase.

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