Goal management training for improving fatigue in children and adolescents with acquired brain injuries: A 2-year follow-up of a randomised controlled trial.

To explore the long-term effectiveness of a paediatric adaptation of Goal Management Training (pGMT), relative to a psychoeducative program (pBHW), in reducing fatigue after pABI 2 years post-intervention. Thirty-eight youths and their parents completed the Paediatric Quality of Life - Multidimensional Fatigue Scale. Primary outcome measures were Total Fatigue Score, General fatigue, Cognitive fatigue, and Sleep/rest fatigue (parent-report). No significant differences in fatigue symptoms by the parental report was observed between the intervention groups at the 2-year follow-up (total score: F = .16, p = .69; general fatigue: F = .36, p = .55; sleep/rest: F = .48, p = .49; and cognitive fatigue: F = .09, p = .76), nor any time*group interactions (total score: F = .25, p = .86; general fatigue: F = .39, p = .76; sleep/rest: F = .20, p = .89; and cognitive fatigue: F = .08, p = .97). In total, 45% of the participants in the pGMT group and 25% in the pBHW group demonstrated a reliable positive clinical change. The significant improvements in fatigue symptoms that were demonstrated 6 months post-intervention could not be confirmed in this 2-year follow-up study. However, a continued positive tendency on most dimensions of fatigue for the participants in the pGMT group could be observed, suggesting that cognitive rehabilitation may help reduce fatigue.

Validity of the Behavioural Assessment of the Dysexecutive Syndrome for Children (BADS-C) in children and adolescents with pediatric acquired brain injury.

The Behavioural Assessment of the Dysexecutive Syndrome for Children (BADS-C) was developed to address the need for a standardized ecologically valid test of executive function (EF) in the pediatric population. Our study aimed to investigate the discriminant, concurrent, and ecological validity of BADS-C in a sample with pediatric acquired brain injury (pABI). Seventy-four participants with pABI aged 10-17 years were included to a pre-registered randomized controlled trial, and baseline assessment was used for the current study. Controls consisted of 60 participants aged 10-17 years. Participants with pABI were assessed with neuropsychological tests and questionnaires of EF, and measurements of general intellectual ability (IQ). Results showed that all BADS-C subtests discriminated between participants with pABI and controls, except for the Playing Cards Test. Concurrent and ecological validity was demonstrated through associations between BADS-C total score, Key Search Test, and Zoo Map Test 1, and neuropsychological tests and teacher questionnaire ratings of EF. Key Search Test and Zoo Map Test 1 predicted teacher ratings of EF, beyond IQ and other neuropsychological test of EF. These findings provide support for BADS-C as a valid clinical assessment tool that can detect everyday executive dysfunction in the pABI population, and guide rehabilitation and treatment decisions.

Metacognitive strategy training versus psychoeducation for improving fatigue in children and adolescents with acquired brain injuries: A randomized controlled trial.

OBJECTIVE: The present study aims to explore the relative effectiveness of two group-based cognitive rehabilitation programs for reducing fatigue in pediatric acquired brain injury (pABI). METHOD: This is an exploratory study of secondary endpoints in a blinded, parallel-randomized controlled trial with children and adolescents (ages 10-17 years) with pABI and reported executive dysfunction. It investigates the effectiveness of a metacognitive program (pediatric goal management training, n = 36) compared to a psychoeducational program (pediatric brain health workshop, n = 37) for reducing fatigue (Pediatric Quality of Life Inventory, Multidimensional Fatigue Scale), 8 weeks and 6 months postintervention. RESULTS: Seventy-three participants completed the allocated interventions, and 71 attended the 6-month follow-up. The results showed a significant decrease in parent-reported fatigue for both interventions from baseline to the 6-month follow-up. Forty percent of the total sample had a reliable change. There was no significant difference between the intervention groups, but a tendency in favor of the psychoeducational approach. Only subscales cognitive and sleep/rest fatigue showed significant reductions. In regression analyses, several factors predicted fatigue at 6 months follow-up, but only better global outcome and executive attention predicted a decrease in fatigue symptoms after 6 months. CONCLUSIONS: Group-based cognitive rehabilitation in the chronic phase of pABI, including education of parents and teachers, may be helpful in reducing fatigue. Global outcome and executive attention at baseline predicted fatigue improvement. Developmental factors are important to consider when tailoring pediatric interventions, as well as modifiable factors associated with fatigue. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Experiences Among School Personnel and School Nurses on Educational Adaptations for Students With CFS/ME: A Qualitative Interview Study.

Introduction: Chronic fatigue syndrome (CFS/ME) is a disabling disease severely impacting school attendance, education, and social life in young students. Uncertainties surrounding CFS/ME etiology may impact the interpretation of CFS/ME in schools. Thus, school personnel need information from health care providers to make adequate adaptations to education and social life at school for these students. Objectives: To explore teachers, counselors, and school nurses' experiences with adapting education for students with CFS/ME aged 13-19 in secondary and high schools. Design: A qualitative study with focus group interviews and individual interviews performed face-to-face or digitally between November 2020 and March 2021. Data were analyzed using Systematic text condensation. Participants: Six teachers, two counselors, and four school nurses in secondary and high school participated. Results: Adapting education for students with CFS/ME was challenging, especially before the students received a diagnosis. The challenges were related to identifying the students' adaptational needs, maintaining a teacher-student relationship due to school absence, difficulties in maintaining continuity of education, and uncertainty regarding the diagnosis. Successful adaptations were related to quickly reacting to school absence, early referral to educational, psychological services, a close collaboration with the school management, and the development of digital teaching for students with CFS/ME. Interdisciplinary collaboration and a clear, constructive plan with adaptive measures, including maintained teacher-student communication and educational and social adaptations, may be useful in preventing the losses, young people, with CFS/ME experience. Conclusion: Early interdisciplinary collaboration to adapt education and social life at school for students with CFS/ME, may support teachers, counselors, and school nurses in their efforts to adapt education and prevent losses related to academic and social development in students with CFS/ME.

Factors related to educational adaptations and social life at school experienced by young people with CFS/ME: a qualitative study.

OBJECTIVES: To explore factors perceived as positive or negative among young people with chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) in relation to school and everyday life. DESIGN: A qualitative study with semistructured individual interviews performed at the local hospital or at the informants' homes between September 2017 and January 2018, with an additional telephone interview to collect data on experiences from the COVID-19 pandemic, conducted in September 2020. Data were analysed using a grounded theory approach. SETTING: The informants were recruited from two university hospitals that offer interdisciplinary assessments of young people with CFS/ME from various parts of Norway. PARTICIPANTS: Five males and 13 females aged 13-21 years with CFS/ME diagnosed 3-56 months prior to the interviews participated. RESULTS: The informants were concerned about a lack of educational adaptations and missed social life at school. Educational and social adaptations could improve schooling and health among young people with CFS/ME. Negative experiences were related to a lack of knowledge about CFS/ME among school personnel and young people's difficulties to limit activities. Online teaching as experienced during the COVID-19 pandemic was described as positive both for education and social life. CONCLUSIONS: Young people with CFS/ME can benefit from better educational adaptations and increased social interaction with peers. From the participants' view, factors that limit learning and socialisation include a lack of knowledge about CFS/ME among teachers and school personnel, expectations from teachers of doing more than they could manage at school, feeling alone coping with the disease and not recognising their own limitations regarding what they are able to do. Suggested factors perceived to enhance learning and socialisation were a better understanding of the disease among school personnel and peers, suitable educational adaptations and being able to socialise with peers.

Fatigue following pediatric acquired brain injury: Interplay with associated factors in a clinical trial population compared to healthy controls.

OBJECTIVE: The aims of the present study were to compare fatigue levels in children with pediatric acquired brain injury (pABI) with healthy controls (HCs), and examine the interplay of fatigue with associated factors. METHOD: We used baseline data from a preregistered randomized controlled trial. Seventy-six children aged 10-17 (median 13 years) with pABI in the chronic phase (88% with confirmatory cerebral imaging findings) and executive function (EF) complaints were included, most with moderate disability according to The Glasgow Outcome Scale Extended (GOSE-E) categorization. HCs consisted of 60 children aged 10-17 (median 13 years). All 127 participants completed measures of fatigue and intelligence. pABI participants were also assessed for behavioral problems, health-related quality of life (HRQoL), and EF. Nonparametric statistics were employed, in addition to a network analysis to model the unique associations between parent-reported fatigue and related factors. RESULTS: Parents reported significantly more fatigue in the pABI-group (75% of scores in clinical range; < 70) compared to HCs (11.7% of scores in clinical range). No strong associations were found between fatigue and injury characteristics, but findings indicated more fatigue in the older than younger age-group for pABI participants. Network modeling revealed a central role for HRQoL, behavioral, and EF symptoms in relation to fatigue. CONCLUSIONS: Fatigue is reported to be highly prevalent in the chronic phase of pABI. When addressing fatigue, our findings demonstrate the advantage of including multidimensional measures of fatigue and examining associated psychological and cognitive constructs, such as HRQoL, behavioral problems, and EF. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Targeting phosphoglycerate dehydrogenase in multiple myeloma.

BACKGROUND: Multiple myeloma (MM) is a hematological malignancy characterized by the clonal expansion of plasma cells in the bone marrow. To date, this disease is still incurable and novel therapeutic approaches are required. Phosphoglycerate dehydrogenase (PHGDH) is the first and rate-limiting enzyme in the de novo serine synthesis pathway, and it has been attributed to bortezomib-resistance in MM. METHODS: Two different PHGDH inhibitors, CBR5884 and NCT-503, were tested against human myeloma cell lines, primary MM cells from patients, and peripheral blood mononuclear cells isolated from healthy donors. The PHGDH inhibitors were then tested in combination with proteasome inhibitors in different MM cell lines, including proteasome-resistant cell lines. Furthermore, we confirmed the effects of PHGDH inhibition through knocking down PHGDH and the effect of NCT-503 in vivo in the 5T33MM mouse model. RESULTS: All the tested myeloma cell lines expressed PHGDH and were sensitive to doses of NCT-503 that were tolerated by peripheral blood mononuclear cells isolated from healthy donors. Upon testing bortezomib in combination with NCT-503, we noticed a clear synergy in several HMCLs. The sensitivity to bortezomib also increased after PHGDH knockdown, mimicking the effect of NCT-503 treatment. Interestingly, targeting PHGDH reduced the intracellular redox capacity of the cells. Furthermore, combination treatment with NCT-503 and bortezomib exhibited a therapeutic advantage in vivo. CONCLUSIONS: Our study shows the therapeutic potential of targeting PHGDH in MM, and suggest it as a way to overcome the resistance to proteasome inhibitors.

Health-related quality of life in Norwegian adolescents living with chronic fatigue syndrome.

PURPOSE: The primary aim was to measure health related quality of life (HRQoL) in a Norwegian cohort of adolescents with Chronic Fatigue Syndrome (CFS/ME). A secondary aim was to identify factors before diagnosis, at time of diagnosis and after diagnosis that were associated with HRQoL. METHODS: In this cross-sectional population-based study, HRQoL was measured by Pediatric Quality of Life Inventory™ Generic Core scale version 4.0 (PedsQL4.0) in 63 adolescents with CFS/ME. In addition, fatigue was measured by PedsQL Multidimensional Fatigue scale (PedsQL-MFS), depressive symptoms were measured by the Short Mood and Feelings Questionnaire (SMFQ), and disruption in school activities was measured by The De Paul Pediatric Health Questionnaire (DPHQ-N). Data were also collected from medical records and patient interviews. RESULTS: Age at diagnosis was 15 (2) years (mean (SD)), and four out of five participants were female. Time from diagnosis to reply was 39 (22) months. Adolescents with CFS/ME reported PedsQL4.0 score 50 (17), and boys reported a better score than girls (64 vs 47, 95% Confidence Interval (CI) for difference (- 27; - 6)). There were positive associations between overall HRQoL and support from a schoolteacher, school attendance or participation in leisure activities. There were negative associations between overall HRQoL and delayed school progression, having been to rehabilitation stay and depressive symptoms. CONCLUSION: HRQoL in adolescents diagnosed with CFS/ME was low. The associations between reported HRQoL, healthcare previously provided, support from a schoolteacher, school attendance and participation in leisure activity may provide information of value when developing refined strategies for healthcare among adolescents with CFS/ME. Possible causal relationships must however be explored in future studies.

Conversion of ATP to adenosine by CD39 and CD73 in multiple myeloma can be successfully targeted together with adenosine receptor A2A blockade.

BACKGROUND: PD1/PDL1-directed therapies have been unsuccessful for multiple myeloma (MM), an incurable cancer of plasma cells in the bone marrow (BM). Therefore, other immune checkpoints such as extracellular adenosine and its immunosuppressive receptor should be considered. CD39 and CD73 convert extracellular ATP to adenosine, which inhibits T-cell effector functions via the adenosine receptor A2A (A2AR). We set out to investigate whether blocking the adenosine pathway could be a therapy for MM. METHODS: Expression of CD39 and CD73 on BM cells from patients and T-cell proliferation were determined by flow cytometry and adenosine production by Liquid chromatograpy-mass spectrometry (HPCL/MS). ENTPD1 (CD39) mRNA expression was determined on myeloma cells from patients enrolled in the publicly available CoMMpass study. Transplantable 5T33MM myeloma cells were used to determine the effect of inhibiting CD39, CD73 and A2AR in mice in vivo. RESULTS: Elevated level of adenosine was found in BM plasma of MM patients. Myeloma cells from patients expressed CD39, and high gene expression indicated reduced survival. CD73 was found on leukocytes and stromal cells in the BM. A CD39 inhibitor, POM-1, and an anti-CD73 antibody inhibited adenosine production and reduced T-cell suppression in vitro in coculture of myeloma and stromal cells. Blocking the adenosine pathway in vivo with a combination of Sodium polyoxotungstate (POM-1), anti-CD73, and the A2AR antagonist AZD4635 activated immune cells, increased interferon gamma production, and reduced the tumor load in a murine model of MM. CONCLUSIONS: Our data suggest that the adenosine pathway can be successfully targeted in MM and blocking this pathway could be an alternative to PD1/PDL1 inhibition for MM and other hematological cancers. Inhibitors of the adenosine pathway are available. Some are in clinical trials and they could thus reach MM patients fairly rapidly.

Paediatric goal management training in patients with acquired brain injury: study protocol for a randomised controlled trial.

INTRODUCTION: Compromised integrity of the brain due to paediatric acquired brain injury (pABI) has been associated with cognitive impairment, particularly executive dysfunction, in addition to somatic and emotional symptoms and reduced everyday function. Goal Management Training (GMT) is a cognitive rehabilitation intervention for improving executive function (EF) that has received empirical support in studies of adults with ABI. The purpose of the present study is to determine the efficacy of a recently developed paediatric version of GMT (pGMT) for children and adolescents with ABI and reported executive dysfunction. METHODS AND ANALYSIS: This study protocol describes a parallel randomised controlled trial including allocation concealment and assessor blinding. Eighty survivors after pABI, aged 10-17 years at the time of intervention, will be recruited. Participants will be randomly allocated to either pGMT (n=40) or a psychoeducative control intervention (n=40; paediatric Brain Health Workshop). Both interventions consist of seven group sessions for participants and parents, followed by external cueing and telephone counselling. The study also includes involvement of teachers. Assessments will be performed at baseline, immediately postintervention and at 6 months' follow-up. Primary outcome measure will be changes in daily life EF as reported by parents (The Behavior Rating Inventory of Executive Function). Secondary outcomes include other assessments of EF (neuropsychological tests and questionnaires). Furthermore, we aim to assess generalisation effects of pGMT on other cognitive functions, as well as emotional, behavioural, adaptive and family function, academic performance, fatigue and quality of life. ETHICS AND DISSEMINATION: Results from this study will be disseminated to relevant research, clinical, health service and patient communities through publications in peer-reviewed and popular science journals, in addition to presentations at scientific conferences. The study will be conducted in accordance with the Helsinki declaration and the Ethical Research Involving Children (ChildWatch International and Unicef). In accordance to Good Clinical Practice our study includes safety and quality monitoring guarantees in compliance with research ethics and safety. The trial will be reported in accordance with the Consolidated Standards of Reporting Trials 2010 statement and Standard Protocol Items for Reporting in Trials recommendations, in addition to being registered at ClinicalTrials.gov. The study has been approved by the Regional Committees for Medical and Health Research Ethics Norway (2017/772). TRIAL REGISTRATION NUMBER: NCT03215342.

Phosphatase of regenerating liver-3 (PRL-3) is overexpressed in classical Hodgkin lymphoma and promotes survival and migration.

BACKGROUND: Phosphatase of regenerating liver-3 (PRL-3) is implicated in oncogenesis of hematological and solid cancers. PRL-3 expression increases metastatic potential, invasiveness and is associated with poor prognosis. With this study, we aimed to show a possible oncogenic role of PRL-3 in classical Hodgkin lymphoma (cHL). METHODS: PRL-3 expression was measured in 25 cHL patients by immunohistochemistry and gene expression was analyzed from microdissected malignant cells. We knocked down PRL-3 in the cHL cell lines L1236 and HDLM2 and used small molecular inhibitors against PRL-3 to investigate proliferation, migration and cytokine production. RESULTS: PRL-3 protein was expressed in 16% of patient samples. In three different gene expression datasets, PRL-3 was significantly overexpressed compared to normal controls. PRL-3 knockdown reduced proliferation, viability and Mcl-1 expression in L1236, but not in HDLM2 cells. Thienopyridone, a small molecule inhibitor of PRL-3, reduced proliferation of both L1236 and HDLM2. PRL-3 affected IL-13 secretion and enhanced STAT6 signaling. IL-13 stimulation partially rescued proliferation in L1236 cells after knockdown of PRL-3. PRL-3 knockdown reduced migration in both L1236 and HDLM2 cells. CONCLUSION: PRL-3 was overexpressed in a subset of cHL patients. Inhibition of PRL-3 increased IL-13 cytokine production and reduced migration, proliferation and viability. The effects could be mediated through regulation of the anti-apoptotic molecule Mcl-1 and a feedback loop of IL-13 mediated activation of STAT6. This point to a role for PRL-3 in the pathogenesis of Hodgkin lymphoma, and PRL-3 could be a possible new drug target.

Strategies parents use to give children oral medicine: a qualitative study of online discussion forums.

AIM: The aim of this study was to describe strategies parents use to give oral medicine to children. METHODS: We conducted an Internet-based qualitative study of posts from online forums where parents discussed how to give children oral medicine. The posts were analyzed using systematic text condensation. The investigators coded and developed groups iteratively, ending up with a consensus on final themes. RESULTS: We included 4581 posts. Parents utilized three main strategies to give oral medicine to children: (1) Open administration give medicine to the child knowingly by changing the palatability, actively involve the child in play or use persuasion; (2) Hidden administration give medicine to the child unknowingly by camouflaging it in food, while sleeping or distracted by another activity; (3) Forced administration force children to take medicine with the use of restraint. Parents expressed three perspectives towards using force: Finding it unproblematic, using force despite not liking it or refusing to use force. No single strategy was described as the obvious first choice, and the strategies were not used in any particular order. Parents who gave up getting their child to ingest the medicine reported to contact the prescriber for a different medication, or stopped the treatment completely. CONCLUSIONS: The three strategies are a robust and precise way to categorize techniques used by parents to give children oral medicine. We suggest that health professionals use the strategies to talk to parents and children about administration of oral medicines.

Effects of exercise intensity and nutrition advice on myocardial function in obese children and adolescents: a multicentre randomised controlled trial study protocol.

INTRODUCTION: The prevalence of paediatric obesity is increasing, and with it, lifestyle-related diseases in children and adolescents. High-intensity interval training (HIIT) has recently been explored as an alternate to traditional moderate-intensity continuous training (MICT) in adults with chronic disease and has been shown to induce a rapid reversal of subclinical disease markers in obese children and adolescents. The primary aim of this study is to compare the effects of HIIT with MICT on myocardial function in obese children and adolescents. METHODS AND ANALYSIS: Multicentre randomised controlled trial of 100 obese children and adolescents in the cities of Trondheim (Norway) and Brisbane (Australia). The trial will examine the efficacy of HIIT to improve cardiometabolic outcomes in obese children and adolescents. Participants will be randomised to (1) HIIT and nutrition advice, (2) MICT and nutrition advice or (3) nutrition advice. Participants will partake in supervised exercise training and/or nutrition sessions for 3 months. Measurements for study end points will occur at baseline, 3 months (postintervention) and 12 months (follow-up). The primary end point is myocardial function (peak systolic tissue velocity). Secondary end points include vascular function (flow-mediated dilation assessment), quantity of visceral and subcutaneous adipose tissue, myocardial structure and function, body composition, cardiorespiratory fitness, autonomic function, blood biochemistry, physical activity and nutrition. Lean, healthy children and adolescents will complete measurements for all study end points at one time point for comparative cross-sectional analyses. ETHICS AND DISSEMINATION: This randomised controlled trial will generate substantial information regarding the effects of exercise intensity on paediatric obesity, specifically the cardiometabolic health of this at-risk population. It is expected that communication of results will allow for the development of more effective evidence-based exercise prescription guidelines in this population while investigating the benefits of HIIT on subclinical markers of disease. TRIAL REGISTRATION NUMBER: NCT01991106.

Phosphatase of regenerating liver 3 (PRL-3) is overexpressed in human prostate cancer tissue and promotes growth and migration.

BACKGROUND: PRL-3 is a phosphatase implicated in oncogenesis in multiple cancers. In some cancers, notably carcinomas, PRL-3 is also associated with inferior prognosis and increased metastatic potential. In this study we investigated the expression of PRL-3 mRNA in fresh-frozen samples from patients undergoing radical prostatectomy because of prostate cancer (PC) and the biological function of PRL-3 in prostate cancer cells. METHODS: Samples from 41 radical prostatectomy specimens (168 samples in total) divided into low (Gleason score ≤ 6), intermediate (Gleason score = 7) and high (Gleason score ≥ 8) risk were analyzed with gene expression profiling and compared to normal prostate tissue. PRL-3 was identified as a gene with differential expression between healthy and cancerous tissue in these analyses. We used the prostate cancer cell lines PC3 and DU145 and a small molecular inhibitor of PRL-3 to investigate whether PRL-3 had a functional role in cancer. Relative ATP-measurement and thymidine incorporation were used to assess the effect of PRL-3 on growth of the cancer cells. We performed an in vitro scratch assay to investigate the involvement of PRL-3 in migration. Immunohistochemistry was used to identify PRL-3 protein in prostate cancer primary tumor and corresponding lymph node metastases. RESULTS: Compared to normal prostate tissue, the prostate cancer tissue expressed a significantly higher level of PRL-3. We found PRL-3 to be present in both PC3 and DU145, and that inhibition of PRL-3 led to growth arrest and apoptosis in these two cell lines. Inhibition of PRL-3 led to reduced migration of the PC3 cells. Immunohistochemistry showed PRL-3 expression in both primary tumor and corresponding lymph node metastases. CONCLUSIONS: PRL-3 mRNA was expressed to a greater extent in prostate cancer tissue compared to normal prostate tissue. PRL-3 protein was expressed in both prostate cancer primary tumor and corresponding lymph node metastases. The results from our in vitro assays suggest that PRL-3 promotes growth and migration in prostate cancer. In conclusion, these results imply that PRL-3 has a role in the pathogenesis of prostate cancer.

Anti-c-MET Nanobody - a new potential drug in multiple myeloma treatment.

BACKGROUND: c-MET is the tyrosine kinase receptor of the hepatocyte growth factor (HGF). HGF-c-MET signaling is involved in many human malignancies, including multiple myeloma (MM). Recently, multiple agents have been developed directed to interfere at different levels in HGF-c-MET signaling pathway. Nanobodies are therapeutic proteins based on the smallest functional fragments of heavy-chain-only antibodies. In this study, we wanted to determine the anticancer effect of a novel anti-c-MET Nanobody in MM. METHODS: We examined the effects of an anti-c-MET Nanobody on thymidine incorporation, migration, adhesion of MM cells, and osteoblastogenesis in vitro. Furthermore, we investigated the effects of the Nanobody on HGF-dependent c-MET signaling by Western blotting. RESULTS: We show that the anti-c-MET Nanobody effectively inhibited thymidine incorporation of ANBL-6 MM cells via inhibition of an HGF autocrine growth loop and thymidine incorporation in INA-6 MM cells induced by exogenous HGF. HGF-induced migration and adhesion of INA-6 were completely and specifically blocked by the Nanobody. Furthermore, the Nanobody abolished the inhibiting effect of HGF on bone morphogenetic protein-2-induced alkaline phosphatase activity and the mineralization of human mesenchymal stem cells. Finally, we show that the Nanobody reduced phosphorylation of tyrosine residues in c-MET, MAPK, and Akt. We also compared the Nanobody with anti-c-MET monoclonal antibodies and revealed the similar or better effect. CONCLUSIONS: The anti-c-MET Nanobody inhibited MM cell migration, thymidine incorporation, and adhesion, and blocked the HGF-mediated inhibition of osteoblastogenesis. The anti-c-MET Nanobody might represent a novel therapeutic agent in the treatment of MM and other cancers driven by HGF-c-MET signaling.

HGF and IGF-1 synergize with SDF-1α in promoting migration of myeloma cells by cooperative activation of p21-activated kinase.

Stromal-derived factor (SDF)-1α, insulin-like growth factor (IGF)-1 and hepatocyte growth factor (HGF) are potent mediators of cell migration. We studied the effect of combinations of these cytokines on the migration of myeloma cells. When SDF-1α was combined with either HGF or IGF-1, we found a striking synergy in the cytokines' ability to guide cells across a transwell membrane. Between HGF and IGF-1 there was no cooperativity. However, the effects of HGF and IGF-1 were not redundant. HGF and SDF-1 caused concentration gradient-directed migration, as opposed to IGF-1, which apparently caused randomly directed cell movement. The SDF-1α-driven migration of JJN-3 cells, a myeloma cell line secreting large amounts of HGF, was reduced when JJN-3 cells were given an inhibitor of the HGF receptor, demonstrating a cooperative activity between autocrine HGF and exogenous SDF-1α. There was a clear positive correlation between the degree of cytokine-induced migration and phosphorylation of p21-activated kinase (PAK) both in primary myeloma cells and in cell lines including INA-6 and IH-1. Downregulation of PAK with small interfering RNA in INA-6 cells resulted in decreased cytokine-driven migration. This study shows synergy between SDF-1α and HGF/IGF-1 in inducing migration of myeloma cells, yet each cytokine has distinct properties in the way it regulates cell migration. These findings are likely to be of clinical relevance because multiple myeloma cells are located in an environment containing HGF and IGF-1 and are exposed to an SDF-1α gradient between the bone marrow and peripheral blood.

High expression of BCL3 in human myeloma cells is associated with increased proliferation and inferior prognosis.

BACKGROUND: BCL3 is a putative oncogene encoding for a protein belonging to the inhibitory kappaB-family. We experienced that this putative oncogene was a common target gene for growth-promoting cytokines in myeloma cell lines. METHODS: Gene expression of BCL3 was studied in 351 newly diagnosed myeloma patients, 12 patients with smouldering myeloma, 44 patients with monoclonal gammopathy of undetermined significance and 22 healthy individuals. Smaller material of samples was included for mRNA detection by RT-PCR, protein detection by Western blot and immunohistochemistry, and for cytogenetic studies. A total of eight different myeloma cell lines were studied. RESULTS: Bcl-3 was induced in myeloma cell lines by interleukin (IL)-6, IL-21, IL-15, tumor necrosis factor-alpha and IGF-1, and its upregulation was associated with increased proliferation of the cells. In a population of 351 patients, expression levels of BCL3 above 75th percentile were associated with shorter 5-yr survival. When this patient population was divided into subgroups based on molecular classification, BCL3 was significantly increased in a poor risk subgroup characterized by overexpression of cell cycle and proliferation related genes. Intracellular localization of Bcl-3 was dependent on type of stimulus given to the cell. CONCLUSION: BCL3 is a common target gene for several growth-promoting cytokines in myeloma cells and high expression of BCL3 at the time of diagnosis is associated with poor prognosis of patients with multiple myeloma (MM). These data may indicate a potential oncogenic role for Bcl-3 in MM.

Hepatocyte growth factor promotes migration of human myeloma cells.

Multiple myeloma is characterized by the accumulation and dissemination of malignant plasma cells in the bone marrow. Cell migration is thought to be important for these events. We studied migration in a Transwell two-chamber assay and tested the motogenic effect of various cytokines. In addition to insulin-like growth factor-1 and stromal cell-derived growth factor-1alpha, previously known as chemoattractants for myeloma cells, we identified hepatocyte growth factor as a potent attractant for myeloma cells. Hepatocyte growth factor-mediated migration was dependent on phosphatidylinositol-3-kinase, involved the MAPK/Erk signaling cascade and VLA-4 integrins, but did not involve Akt, mTOR or G proteins.

Human myeloma cells adhere to fibronectin in response to hepatocyte growth factor.

BACKGROUND AND OBJECTIVES: Multiple myeloma is characterized by an accumulation of malignant plasma cells in the bone marrow. Inside the bone marrow, adhesion of myeloma cells to extracellular matrix proteins such as fibronectin may promote cell survival and induce drug resistance. In this work we examined the effect of hepatocyte growth factor (HGF) on the adhesion of myeloma cells and the signaling pathways involved. DESIGN AND METHODS: Cell adhesion experiments were performed with the human myeloma cell line INA-6 and primary myeloma cells. The HGF signaling pathway was studied in INA-6 cells with the use of antibodies against VLA-4 integrin, and with inhibitors of various intracellular signaling molecules. RESULTS: We found that HGF stimulated adhesion of myeloma cells to fibronectin. This event was dependent on the alpha4 and beta1 integrin subunits (VLA-4), but HGF did not increase the expression of integrins on the cell surface. Our findings suggest that HGF promotes myeloma cells to adhere via activation of the phosphatidylinositol 3-kinase (PI3K) pathway independently of AKT, but possibly through the involvement of nuclear factor kappa B (NF-kappaB). INA-6 cells adhered to fibronectin after stimulation by insulin-like growth factor or stromal cell-derived factor 1alpha, but this adhesion was less dependent on PI3K than HGF-mediated adhesion. INTERPRETATION AND CONCLUSIONS: his work points to HGF as a pro-adhesive factor in cell adherence to the bone marrow matrix protein fibronectin, an event known to promote cancer cell survival and drug resistance. Inhibiting HGF, its receptor c-Met or the VLA-4 integrin may be beneficial to the myeloma patient.

A selective c-met inhibitor blocks an autocrine hepatocyte growth factor growth loop in ANBL-6 cells and prevents migration and adhesion of myeloma cells.

PURPOSE: We wanted to examine the role of the hepatocyte growth factor (HGF) receptor c-Met in multiple myeloma by applying a novel selective small molecule tyrosine kinase inhibitor, PHA-665752, directed against the receptor. EXPERIMENTAL DESIGN: Four biological sequels of HGF related to multiple myeloma were studied: (1) proliferation of myeloma cells, (2) secretion of interleukin-11 from osteogenic cells, (3) migration of myeloma cells, and (4) adhesion of myeloma cells to fibronectin. We also examined effects of the c-Met inhibitor on intracellular signaling pathways in myeloma cells. RESULTS: PHA-665752 effectively blocked the biological responses to HGF in all assays, with 50% inhibition at 5 to 15 nmol/L concentration and complete inhibition at around 100 nmol/L. PHA-665752 inhibited phosphorylation of several tyrosine residues in c-Met (Tyr(1003), Tyr(1230/1234/1235), and Tyr(1349)), blocked HGF-mediated activation of Akt and p44/42 mitogen-activated protein kinase, and prevented the adaptor molecule Gab1 from complexing with c-Met. In the HGF-producing myeloma cell line ANBL-6, PHA-665752 revealed an autocrine HGF-c-Met-mediated growth loop. The inhibitor also blocked proliferation of purified primary myeloma cells, suggesting that autocrine HGF-c-Met-driven growth loops are important for progression of multiple myeloma. CONCLUSIONS: Collectively, these findings support the role of c-Met and HGF in the proliferation, migration, and adhesion of myeloma cells and identify c-Met kinase as a therapeutic target for treatment of patients with multiple myeloma.