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R Lai

Publications and source records attributed to R Lai.

At least 19 recordsLinked to original sources

Restoration of shp1 expression by 5-AZA-2'-deoxycytidine is associated with downregulation of JAK3/STAT3 signaling in ALK-positive anaplastic large cell lymphoma.

Anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALK+ ALCL) is characterized by constitutive activation of the Janus kinase (JAK)3/signal transducers and activators of transcription 3 (STAT3) signaling pathway. SHP1, a tyrosine phosphatase that negatively regulates JAK/STAT, is frequently absent in ALK+ ALCL owing to gene methylation. To test the hypothesis that loss of SHP1 contributes to JAK3/STAT3 activation in ALK+ ALCL cells, we induced SHP1 expression using 5-aza-2'-deoxycytidine (5-AZA), an inhibitor of DNA methyltransferase, in ALK+ ALCL cell lines, and correlated with changes in the JAK3/STAT3 pathway. 5-AZA gradually restored SHP1 expression in Karpas 299 and SU-DHL-1 cells over 5 days. The initially low level of SHP1 expression did not result in significant changes to the expression or tyrosine phosphorylation of JAK3 and STAT3. However, higher levels of SHP1 seen subsequently correlated with substantial decreases in JAK3 and pJAK3, followed by pSTAT3 (but not STAT3). Importantly, the decrease in JAK3 was abrogated by MG132, a proteasome inhibitor. 5-AZA induced no significant increase in apoptosis but it sensitized ALCL cells to doxorubicin-induced apoptosis. Our findings support the concept that loss of SHP1 contributes to the constitutive activation of JAK3/STAT3 in ALK+ ALCL cells. SHP1 appears to downregulate JAK3 by two mechanisms: tyrosine dephosphorylation and increased degradation via the proteasome pathway.

Anaplastic Lymphoma Kinase↗

Cryptococcosis in apparently immunocompetent patients.

BACKGROUND: Few reports have described the clinical and microbiological features of cryptococcosis in immunocompetent patients. AIM: To compare clinical presentations and outcomes of cryptococcosis in immunocompetent vs. immunocompromised patients. DESIGN: Retrospective case series. METHODS: All culture- or histology-confirmed cases (n = 46) of cryptococcosis in two acute hospitals in Hong Kong (1995-2005) were included. Clinical presentations, rates of fungaemia, cerebrospinal fluid (CSF) parameters and clinical outcomes were recorded. RESULTS: Twenty patients (43.5%) were apparently immunocompetent, 17 (37.0%) had predisposing factors other than HIV infection, and 9 (19.6%) were HIV-positive. Thirty-one (67.4%) presented with meningitis, four (8.7%) with pulmonary cryptococcosis, and 11 (23.9%) with extraneural, extrapulmonary cryptococcosis. Of the immunocompetent patients with retrievable isolates (n = 8), three (37.5%) were Cryptococcus gattii; all isolates (n = 6) from immunocompromised patients were Cryptococcus neoformans var. grubii. Immunocompetent patients more commonly presented with meningitis (80.0% vs. 47.1%, p = 0.03), and tended toward lower rates of fungaemia (10.0% vs. 35.3%, p = 0.06) and mortality (25.0% vs. 52.9%, p = 0.06). Death was associated with fungaemia (p = 0.01) and underlying malignancy (p < 0.01). In cryptococcal meningitis, immunocompetent patients had longer mean time from illness onset to presentation (34.4 vs. 12.6 days, p = 0.02), more intense inflammatory responses (CSF: white blood cells 108 vs. 35 x 10(9)/l, p = 0.03; protein 1.61 g/l vs. 0.79 g/l, p = 0.07), less fungaemia (0% vs. 26.7%, p = 0.04) and more satisfactory clinical outcomes (81.3% vs. 46.7%, p = 0.04). DISCUSSION: A substantial proportion of patients with cryptococcosis are apparently immunocompetent. C. neoformans var. grubii and C. gattii are the common causes. Immunocompetent patients tend to present with localized, indolent neurological disease, with more intense inflammatory responses but better clinical outcomes.

Adult↗

STAT3 is activated in a subset of the Ewing sarcoma family of tumours.

STAT3 is an oncogene that regulates critical cellular processes and whose constitutive activation has been demonstrated to correlate with biological and clinical features in many types of human malignancy. In this study, STAT3 activation was assessed in the Ewing sarcoma family of tumours (ESFT), which is characterized by fusion of the EWS gene with one of several Ets transcription factors, most commonly EWS-FLI1. STAT3 activation was assessed by immunohistochemistry using a monoclonal antibody specific for tyrosine(705)-phosphorylated STAT3 (pSTAT3(tyr705)) and a tissue microarray containing 49 paraffin-embedded ESFT tumours with known EWS translocations. Twenty-five (51%) tumours were pSTAT3(tyr705)-positive, as defined by more than 10% tumour cell immunostaining. STAT3 activation correlated with tumour site at presentation, with pSTAT3(tyr705)-negative ESFT involving axial sites predominantly (p = 0.008). Notably, among 31 patients who presented with localized disease, high-level STAT3 activation correlated with better overall survival (p = 0.02). STAT3 activation was not directly related to EWS-FLI1 expression, since EWS-FLI1 transfection did not result in STAT3 activation. Furthermore, detailed molecular analysis indicated that STAT3 activation may be seen with EWS-FLI1 or EWS-ERG and appears to be independent of EWS-FLI1 fusion type. In conclusion, STAT3 activation is present in approximately half of ESFT and correlates with clinical features. The role of STAT3 activation in ESFT pathogenesis seems to be independent of the type of EWS/Ets translocation.

Adolescent↗

Different breakage-prone regions on chromosome 1 detected in t(11;14)-positive mantle cell lymphoma cell lines and multiple myeloma cell lines are associated with different tumor progression-related mechanisms.

To better define secondary aberrations that occur in addition to translocation t(11;14)(q13;q32) in mantle cell lymphomas (MCL) and in multiple myelomas (MM), seven t(11;14)-positive MCL cell lines and four t(11;14)-positive MM cell lines were analysed by fluorescence R-banding and spectral karyotyping (SKY). Compared with published data obtained by G-banding, most chromosome aberrations were redefined or further specified. Furthermore, several additional chromosome aberrations were identified. Thus, these cytogenetically well defined t(11;14)-positive MCL and MM cell lines may be useful tools for the identification and characterization of genes that might be involved in the pathogenesis of MCL and MM, respectively. Since MCL and MM were found to have different alterations of chromosome 1, these were investigated in more detail by fluorescence in situ hybridization (FISH) and multicolor banding (MCB) analyses. The most frequently altered and deletion-prone loci in MCL cell lines were regions 1p31 and 1p21. In contrast, breakpoints in MM cell lines most often involved the heterochromatic regions 1p12-->p11, and the subcentromeric regions 1q12 and 1q21. These data are in accordance with previously published data of primary lymphomas. Our findings may indicate that different pathways of clonal evolution are involved in these morphologically distinct lymphomas harboring an identical primary chromosome aberration, t(11;14).

Cell Line, Tumor↗

Interactive Health Communication Applications for people with chronic disease.

BACKGROUND: Interactive Health Communication Applications (IHCAs) are computer-based, usually web-based, information packages for patients that combine health information with at least one of social support, decision support, or behaviour change support. These are innovations in health care and their effects on health are uncertain. OBJECTIVES: To assess the effects of IHCAs for people with chronic disease. SEARCH STRATEGY: We designed a four-part search strategy. First, we searched electronic bibliographic databases for published work; second, we searched the grey literature; and third, we searched for ongoing and recently completed clinical trials in the appropriate databases. Finally, researchers of included studies were contacted, and reference lists from relevant primary and review articles were followed up. As IHCAs require relatively new technology, the search time period commenced at 1990, where possible, and ran until 31 December 2003. SELECTION CRITERIA: Randomised controlled trials (RCTs) of IHCAs for adults and children with chronic disease. DATA COLLECTION AND ANALYSIS: One reviewer screened abstracts for relevance. Two reviewers screened all candidate studies to determine eligibility, apply quality criteria, and extract data from included studies. Authors of included RCTs were contacted for missing data. Results of RCTs were pooled using random-effects model with standardised mean differences (SMDs) for continuous outcomes and odds ratios for binary outcomes; heterogeneity was assessed using the I(2 )statistic. MAIN RESULTS: We identified 24 RCTs involving 3739 participants which were included in the review.IHCAs had a significant positive effect on knowledge (SMD 0.46; 95% confidence interval (CI) 0.22 to 0.69), social support (SMD 0.35; 95% CI 0.18 to 0.52) and clinical outcomes (SMD 0.18; 95% CI 0.01 to 0.35). Results suggest it is more likely than not that IHCAs have a positive effect on self-efficacy (a person's belief in their capacity to carry out a specific action) (SMD 0.24; 95% CI 0.00 to 0.48). IHCAs had a significant positive effect on continuous behavioural outcomes (SMD 0.20; 95% CI 0.01 to 0.40). Binary behavioural outcomes also showed a positive effect for IHCAs, although this result was not statistically significant (OR 1.66; 95% CI 0.71 to 3.87). It was not possible to determine the effects of IHCAs on emotional or economic outcomes. AUTHORS' CONCLUSIONS: IHCAs appear to have largely positive effects on users, in that users tend to become more knowledgeable, feel better socially supported, and may have improved behavioural and clinical outcomes compared to non-users. There is a need for more high quality studies with large sample sizes to confirm these preliminary findings, to determine the best type and best way to deliver IHCAs, and to establish how IHCAs have their effects for different groups of people with chronic illness.

Adaptation, Psychological↗

A systematic review of the scientific evidence for the efficacy of a palliative care approach in advanced dementia.

BACKGROUND: Patients with dementia often receive poor end-of-life care, with inadequate pain control and without access to the palliative care services that patients with cancer are offered. This has been identified as an area of need in recent UK. Government reports and by the Alzheimer's Society (UK). Our objective was to perform a systematic review of the scientific literature regarding the efficacy of a palliative care model in patients with dementia. METHODS: A systematic review was carried out to identify controlled trials that investigated the efficacy of palliative care in patients with dementia. Data sources included were Medline, EMBASE, PsycINFO, CINAHL, British Nursing Index, AMED, Cochrane Database of Systematic Reviews, Web of Science, Cochrane Central Register of Controlled Trials, International Standard Randomised Controlled Trial register, the NHS Economic Evaluation Database and the System for Information on Grey Literature in Europe. Other data was sourced from hand searches of papers identified on electronic databases and review articles. RESULTS: The search identified 30 review articles, but only four papers were eligible for full appraisal and only two of these met the full criteria for inclusion. These papers gave equivocal evidence of the efficacy for a palliative model of care in dementia. CONCLUSION: Despite the increased interest in palliative care for patients with dementia there is currently little evidence on which to base such an approach. This may in part be due to the ethical difficulties surrounding such research, prognostic uncertainty in clinicians and the lack of clear outcome measures for patients who are unable to express their needs or wishes. Further systematic research is urgently needed to educate an important and developing area of clinical practice.

Aged↗

p53 gene mutations are uncommon but p53 is commonly expressed in anaplastic large-cell lymphoma.

Anaplastic large-cell lymphoma (ALCL), as defined in the World Health Organization, is a heterogeneous category in which a subset of cases is associated with the t(2;5)(p23;q35) or variant translocations resulting in overexpression of anaplastic lymphoma kinase (ALK). p53 has not been assessed in currently defined subsets of ALCL tumors. In this study, we assessed ALK+ and ALK- ALCL tumors for p53 gene alterations using PCR, single-strand conformation polymorphism and direct sequencing methods. We also immunohistochemically assessed ALCL tumors for p53 expression. Three of 36 (8%) ALCL tumors (1/14 ALK+, 2/22 ALK-) with adequate DNA showed p53 gene mutations. By contrast, p53 was overexpressed in 36 of 55 (65%) ALCL tumors (16 ALK+, 20 ALK-). p21, a target of p53, was expressed in 15 of 31 (48%) ALCL tumors including seven of 15 (47%) p53-positive tumors. p21 expression in a subset of ALCL suggests the presence of functional p53 protein. Apoptotic rate was significantly higher in p53-positive than p53-negative tumors (mean 2.78 vs 0.91%, P = 0.0003). We conclude that the p53 gene is rarely mutated in ALK+ and ALK- ALCL tumors. Nevertheless, wild-type p53 gene product is commonly overexpressed in ALCL and may be functional in a subset of these tumors.

Adult↗

Conceptual framework and systematic review of the effects of participants' and professionals' preferences in randomised controlled trials.

OBJECTIVES: To develop a conceptual framework of preferences for interventions in the context of randomised controlled trials (RCTs), as well as to examine the extent to which preferences affect recruitment to RCTs and modify the measured outcome in RCTs through a systematic review of RCTs that incorporated participants' and professionals' preferences. Also to make recommendations on the role of participants' and professionals' preferences in the evaluation of health technologies. DATA SOURCES: Electronic databases. REVIEW METHODS: The conceptual review was carried out on published papers in the psychology and economics literature concerning concepts of relevance to patient decision-making and preferences, and their measurement. For the systematic review, studies across all medical specialities meeting strict criteria were selected. Data were then extracted, synthesised and analysed. RESULTS: Key elements for a conceptual framework were found to be that preferences are evaluations of an intervention in terms of its desirability and these preferences relate to expectancies and perceived value of the process and outcome of interventions. RCTs differed in the information provided to patients, the complexity of techniques used to provide that information and the degree to which preference elicitation may simply produce pre-existing preferences or actively construct them. Most current RCTs used written information alone. Preference can be measured in many different ways and most RCTs did not provide quantitative measures of preferences, and those that did tended to use very simple measures. The second part of the study, the systematic review included 34 RCTs. The findings gave support to the hypothesis that preferences affect trial recruitment. However, there was less evidence that external validity was seriously compromised. There was some evidence that preferences influenced outcome in a proportion of trials. However, evidence for preference effects was weaker in large trials and after accounting for baseline differences. Preference effects were also inconsistent in direction. There was no evidence that preferences influenced attrition. Therefore, the available evidence does not support the operation of a consistent and important 'preference effect'. Interventions cannot be categorised consistently on degree of participation. Examining differential preference effects based on unreliable categories ran the risk of drawing incorrect conclusions, so this was not carried out. CONCLUSIONS: Although patients and physicians often have intervention preferences, our review gives less support to the hypothesis that preferences significantly compromise the internal and external validity of trials. This review adds to the growing evidence that when preferences based on informed expectations or strong ethical objections to an RCT exist, observational methods are a valuable alternative. All RCTs in which participants and/or professionals cannot be masked to treatment arms should attempt to estimate participants' preferences. In this way, the amount of evidence available to answer questions about the effect of treatment preferences within and outwith RCTs could be increased. Furthermore, RCTs should routinely attempt to report the proportion of eligible patients who refused to take part because of their preferences for treatment. The findings also indicate a number of approaches to the design, conduct and analysis of RCTs that take account of participants' and/or professionals' preferences. This is referred to as a methodological tool kit for undertaking RCTs that incorporate some consideration of patients' or professionals' preferences. Future research into the amount and source of information available to patients about interventions in RCTs could be considered, with special emphasis on the relationship between sources inside and outside the RCT context. Qualitative research undertaken as part of ongoing RCTs might be especially useful. The processes by which this information leads to preferences in order to develop or extend the proposed expectancy--value framework could also be examined. Other areas for consideration include: how information about interventions changes participants' preferences; a comparison of the feasibility and effectiveness of different informed consent procedures; how strength of preference varies for different interventions within the same RCT and how these differences can be taken account of in the analysis; the differential effects of patients' and professionals' preferences on evidence arising from RCTs; and whether the standardised measurement of preferences within all RCTs (and analysis of the effect on outcome) would allow the rapid development of a significant evidence base concerning patient preferences, albeit in relation to a single preference design.

Attitude of Health Personnel↗

Interactive Health Communication Applications for people with chronic disease.

BACKGROUND: Interactive Health Communication Applications (IHCAs) are computer-based, usually web-based health information packages for patients that combine information with at least one of social support, decision support, or behaviour change support. These are innovations in health care and their effects on health are uncertain. OBJECTIVES: To assess the effects of IHCAs for people with chronic disease. SEARCH STRATEGY: We designed a four-part search strategy. First, we searched electronic bibliographic databases for published work; second, we searched the grey literature and third, we searched for ongoing and recently completed clinical trials in the appropriate databases. Finally, researchers of included studies were contacted, and reference lists from relevant primary and review articles were followed up. As IHCAs require relatively new technology, the search commenced at 1990 where possible. SELECTION CRITERIA: Randomised controlled trials (RCTs) of Interactive Health Communication Applications for adults and children with chronic disease. DATA COLLECTION AND ANALYSIS: One reviewer screened abstracts. Two reviewers screened all candidate studies to determine eligibility, apply quality criteria, and extract data from included studies. Authors of included RCTs were contacted for missing data. Results of RCTs were pooled using a random effects model and standardised mean differences (SMDs) were calculated to provide net effect sizes. MAIN RESULTS: We screened 24,757 unique citations and retrieved 958 papers for further assessment, yielding 28 RCTs involving 4042 participants. One of these had an inadequate method of concealment of allocation, and sensitivity analyses were performed to determine the effects of including or excluding these data in the meta-analyses. Results in the abstract are from the meta-analyses excluding data from this study.IHCAs were found to have a positive effect on knowledge (SMD 0.49; 95% confidence interval (CI) 0.14 to 0.84) and on social support (SMD 0.47; 95% CI 0.28 to 0.66). IHCAs were found to have no effect on self-efficacy (SMD 0.15; 95% CI -0.13 to 0.43) or behavioural outcomes (SMD -0.09; 95% CI -0.49 to 0.32). IHCAs had a negative effect on clinical outcomes (SMD -0.32; 95% CI -0.63 to -0.02). REVIEWERS' CONCLUSIONS: The number and range of IHCAs is increasing rapidly; however there is a shortage of high quality evaluative data. Consumers who wish to increase their knowledge or social support amongst people with a similar problem may find an IHCA helpful. However, consumers whose primary aim is to achieve optimal clinical outcomes should not use an IHCA at present. Further research is needed to determine the reason for this negative effect on clinical outcomes, whether an optimal IHCA can achieve behaviour change and improved health outcomes, and if so, what are the essential features of such an IHCA, and the extent to which they differ according to patient group or condition.

Retraction of Publication as Topic↗

Isolation measures in the hospital management of methicillin resistant Staphylococcus aureus (MRSA): systematic review of the literature.

OBJECTIVE: To evaluate the evidence for the effectiveness of isolation measures in reducing the incidence of methicillin resistant Staphylococcus aureus (MRSA) colonisation and infection in hospital inpatients. DESIGN: Systematic review of published articles. DATA SOURCES: Medline, Embase, CINAHL, Cochrane Library, System for Information on Grey Literature in Europe (SIGLE), and citation lists (1966-2000). REVIEW METHODS: Articles reporting MRSA related outcomes and describing an isolation policy were selected. No quality restrictions were imposed on studies using isolation wards or nurse cohorting. Other studies were included if they were prospective or employed planned comparisons of retrospective data. RESULTS: 46 studies were accepted; 18 used isolation wards, nine used nurse cohorting, and 19 used other isolation policies. Most were interrupted time series, with few planned formal prospective studies. All but one reported multiple interventions. Consideration of potential confounders, measures to prevent bias, and appropriate statistical analysis were mostly lacking. No conclusions could be drawn in a third of studies. Most others provided evidence consistent with a reduction of MRSA acquisition. Six long interrupted time series provided the strongest evidence. Four of these provided evidence that intensive control measures including patient isolation were effective in controlling MRSA. In two others, isolation wards failed to prevent endemic MRSA. CONCLUSION: Major methodological weaknesses and inadequate reporting in published research mean that many plausible alternative explanations for reductions in MRSA acquisition associated with interventions cannot be excluded. No well designed studies exist that allow the role of isolation measures alone to be assessed. None the less, there is evidence that concerted efforts that include isolation can reduce MRSA even in endemic settings. Current isolation measures recommended in national guidelines should continue to be applied until further research establishes otherwise.

Cross Infection↗

Methicillin-resistant Staphylococcus aureus in hospitals and the community: stealth dynamics and control catastrophes.

Methicillin-resistant Staphylococcus aureus (MRSA) represents a serious threat to the health of hospitalized patients. Attempts to reduce the spread of MRSA have largely depended on hospital hygiene and patient isolation. These measures have met with mixed success: although some countries have almost eliminated MRSA or remained largely free of the organism, others have seen substantial increases despite rigorous control policies. We use a mathematical model to show how these increases can be explained by considering both hospital and community reservoirs of MRSA colonization. We show how the timing of the intervention, the level of resource provision, and chance combine to determine whether control measures succeed or fail. We find that even control measures able to repeatedly prevent sustained outbreaks in the short-term can result in long-term control failure resulting from gradual increases in the community reservoir. If resources do not scale with MRSA prevalence, isolation policies can fail "catastrophically."

Community-Acquired Infections↗

Accurate diagnosis of pancreas divisum by linear-array endoscopic ultrasonography.

BACKGROUND AND STUDY AIMS: During linear-array endoscopic ultrasonography (EUS), the main pancreatic duct can be followed continuously from the major papilla into the pancreatic body in most patients. Often, the duct can also be seen crossing a sonographic border between the ventral and dorsal pancreatic anlagen. It was hypothesized that the presence of either feature excludes pancreas divisum, whereas the absence of these features suggests complete pancreas divisum. PATIENTS AND METHODS: Pancreas divisum was sought during all linear-array EUS examinations conducted between July 1999 and June 2003. Charts were reviewed retrospectively, and patients who underwent endoscopic retrograde pancreatography after, but not before, EUS were included in the study. RESULTS: A total of 162 patients had EUS before ERCP. Adequate evaluation of the pancreatic duct was possible in 78 % of the patients. The prevalence of pancreas divisum was 13.6 %. In patients with adequate duct visualization, the sensitivity, specificity, and positive and negative predictive values for EUS were 95 %, 97 %, 86 %, and 99 %, respectively. The overall accuracy of EUS for identifying pancreas divisum was 97 % in this subgroup. CONCLUSION: Adequate EUS evaluation of pancreas divisum was possible in most cases. Linear-array EUS is a promising diagnostic test for pancreas divisum.

Endosonography↗

Systematic review of isolation policies in the hospital management of methicillin-resistant Staphylococcus aureus: a review of the literature with epidemiological and economic modelling.

OBJECTIVE: To review the evidence for the effectiveness of different isolation policies and screening practices in reducing the incidence of methicillin-resistant Staphylococcus aureus (MRSA) colonisation and infection in hospital in-patients. To develop transmission models to study the effectiveness and cost-effectiveness of isolation policies in controlling MRSA. DATA SOURCES: MEDLINE, EMBASE, CINAHL, The Cochrane Library and SIGLE (1966-2000). Hand-searching key journals. No language restrictions. REVIEW METHODS: Key data were extracted from articles reporting MRSA-related outcomes and describing an isolation policy in a hospital with epidemic or endemic MRSA. No quality restrictions were imposed on studies using isolation wards (IW) or nurse cohorting (NC). Other studies were included if they were prospective or employed planned comparisons of retrospective data. Stochastic and deterministic models investigated long-term transmission dynamics, studying the effect of a fixed capacity IW, producing economic evaluations using local cost data. RESULTS: A total of 46 studies were accepted: 18 IWs, 9 NC, 19 other isolation policies. Most were interrupted time series, with few planned formal prospective studies. All but one reported multiple interventions. Consideration of potential confounders, measures to prevent bias, and appropriate statistical analysis were mostly lacking. No conclusions could be drawn in a third of studies. Most others provided evidence consistent with reduction of MRSA acquisition. Six long interrupted time series provided the strongest evidence. Four of these provided evidence that intensive control measures which included patient isolation were effective in controlling MRSA. In two others IW use failed to prevent endemic MRSA. There was no robust economic evaluation. Models showed that improving the detection rate or ensuring adequate isolation capacity reduced endemic levels, with substantial savings achievable. CONCLUSIONS: Major methodological weaknesses and inadequate reporting in published research mean that many plausible alternative explanations for reductions in MRSA acquisition associated with interventions cannot be excluded. No well-designed studies allow the role of isolation measures alone to be assessed. Nonetheless, there is evidence that concerted efforts that include isolation can reduce MRSA even when endemic. Little evidence was found to suggest that current isolation measures recommended in the UK are ineffective, and these should continue to be applied until further research establishes otherwise. The studies with the strongest evidence, together with the results of the modelling, provide testable hypotheses for future research. Guidelines to facilitate design of future research are produced.

Cost-Benefit Analysis↗

Establishment and characterization of a new mantle cell lymphoma cell line, Mino.

Mantle cell lymphoma (MCL) is a distinct type of B-cell non-Hodgkin's lymphoma characterized by cyclin D1 overexpression and the cytogenetic abnormality, the t(11;14)(q13;q32). MCL cell lines have been difficult to establish and in vitro studies of these neoplasms are scarce. We describe the establishment and characteristics of a new MCL cell line, Mino. The cells are large, growing singly and in small clumps in vitro. By flow cytometry, the immunophenotype was compatible with MCL (i.e. CD5+CD20+CD23-FMC7+). Conventional cytogenetics showed hyperdiploidy with multiple complex karyotypic abnormalities, but no evidence of the t(11;14), proven to be present only by fluorescence in situ hybridization and polymerase chain reaction (PCR) methods. Western blots showed expression of cyclin D1 but no detectable cyclin D2 and cyclin D3; the retinoblastoma protein was predominantly phosphorylated. There was expression of tumor suppressor gene products including p53, p16(INK4a), and p21(WAF1). Sequencing of the TP53 gene revealed a mutation (codon 147(valine-->glycine)) in exon 5. Epstein Barr virus was absent. In summary, Mino is a new MCL cell line that may be useful to study the pathogenesis of MCL.

Amino Acid Substitution↗