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Diffuse large B-cell lymphoma - tumour characteristics on RNA and protein level associated with prognosis

Linderoth, Johan LU (2007)
Abstract (Swedish)
Popular Abstract in Swedish

Diffust storcelligt B-celllymfom (DLBCL) är den vanligaste aggressiva lymfomsjukdomen, och drabbar ca 450 personer årligen i Sverige. Med modern antracyklin-innehållande cytostatikabehandling är DLBCL en potentiellt botbar sjukdom. Av patienter med lokaliserad sjukdom botas 70 %, med spridd sjukdom ca 50 %.



Bakgrunden till arbete 1 i denna avhandling var en rapport där man med hjälp av genuttrycksprofilering av DLBCL funnit att patienter vars tumörer hade tydliga drag av gener aktiverade under den normala B-cellens germinalcenterfas (GC) hade betydligt bättre överlevnad än de patienter vars tumörer hade drag av ?aktiverade B-lymfocyter? (ABC)(Alizadeh et al, Nature... (More)
Popular Abstract in Swedish

Diffust storcelligt B-celllymfom (DLBCL) är den vanligaste aggressiva lymfomsjukdomen, och drabbar ca 450 personer årligen i Sverige. Med modern antracyklin-innehållande cytostatikabehandling är DLBCL en potentiellt botbar sjukdom. Av patienter med lokaliserad sjukdom botas 70 %, med spridd sjukdom ca 50 %.



Bakgrunden till arbete 1 i denna avhandling var en rapport där man med hjälp av genuttrycksprofilering av DLBCL funnit att patienter vars tumörer hade tydliga drag av gener aktiverade under den normala B-cellens germinalcenterfas (GC) hade betydligt bättre överlevnad än de patienter vars tumörer hade drag av ?aktiverade B-lymfocyter? (ABC)(Alizadeh et al, Nature 2000).



Eftersom genuttrycksprofilering är kostnadskrävande och tekniskt komplicerat ville vi i



studie 1 undersöka om man på ett enklare sätt kunde identifiera GC eller ABC profiler på proteinnivå med hjälp av immunhistokemi. Med hjälp av etablerade germinalcentermarkörer, CD10 och BCL6, och en förmodad postgerminalcentermarkör, CD138, kunde vi inte med hjälp av immunhistokemi identifiera prognostiskt skilda subgrupper i en grupp av 125 patienter, stad II-IV som cytostatikabehandlats pga DLBCL. Frekvensen av BCL6-positiva tumörer var ovanligt hög, 97 %, möjligen beroende på att den immunhistokemiska teknik som använts, EnVision metoden, var känsligare än äldre metoder. I studien användes också ytterligare två markörer för att identifiera germinalcenterfasen, CD23 och CD40, vars uttryck korrelerade med varandra men inte med de andra undersökta markörerna. Uttryck av CD23 och/eller CD40 var förenat med förlängd överlevnad för patienterna.



I studie 2 kunde den prognostiskt gynnsamma effekten av CD40, men inte CD23, verifieras i ett nytt patientmaterial bestående av 125 patienter, stad II-IV, som cytostatikabehandlats pga DLBCL. CD40-effekten kunde inte förklaras av en association med GC-fenotypen och heller inte av ett ökat autologt tumörcellssvar, mätt som grad av tumörinfiltrerande hjälpar- och mördar-T-celler. Den prognostiskt gynnsamma effekten av en GC-fenotyp, definierad enl. Hans et al (Blood 2004), kunde påvisas.



I studie 3 bekräftades misstanken att bruket av EnVision-tekniken, numera en standardmetod för påvisandet av immunohistokemiska reaktioner, i sig leder till en högre frekvens av BCL6-positivitet än vad användandet av äldre immunhistokemiska metoder gör. Vidare konstaterades att användandet av s.k. tissue microarrayteknik (TMA) inte lämpar sig för att bestämma om tumörer ska klassas som GC eller icke-GC. Detta beror framförallt på att BCL6 färgar in ojämnt, med hög risk för falskt negativa resultat.



I studie 4 studerades genuttrycksprofilerna i DLBCL-tumörer från 24 patienter med botad sjukdom och 13 patienter med cytostatika-resistent sjukdom. De gener som bäst förmådde att skilja grupperna kodade i huvudsak för proteiner som uttrycks av celler i tumörernas omgivning, och inte för proteiner som uttrycks av tumörcellerna själva. Detta bekräftades genom imunhistokemiska analyser, där höga gennivåer motsvarades av ett högre proteinuttryck. I den botade gruppen var andelen tumörer som uttryckte proteiner som är inblandade i olika inflammatoriska processer mycket större än i den refraktära gruppen. Vidare analyser visade att dessa proteiner var lokaliserade i makrofager som, liksom tumörinfiltrerande mördarceller, mycket oftare fanns i tumörer från den botade gruppen. (Less)
Abstract
Diffuse large B-cell lymphoma (DLBCL) is the most frequent lymphoma subtype. In Sweden 450 new cases are diagnosed annually. With modern anthracycline-containing chemotherapy DLBCL is potentially curable, with an estimated overall cure rate of approximately 50% for patients with advanced stage disease. Through molecular profiling of DLBCL the ?cell-of-origin concept? has been established: patients with tumours expressing genes characteristic of germinal center B-cells, ?GC-profile? has a significantly better survival than patients with tumors expressing genes normally induced during in vitro activation of peripheral blood



B-cells, ?ABC-profile?.



The first study (n=125) aimed to identify a protein... (More)
Diffuse large B-cell lymphoma (DLBCL) is the most frequent lymphoma subtype. In Sweden 450 new cases are diagnosed annually. With modern anthracycline-containing chemotherapy DLBCL is potentially curable, with an estimated overall cure rate of approximately 50% for patients with advanced stage disease. Through molecular profiling of DLBCL the ?cell-of-origin concept? has been established: patients with tumours expressing genes characteristic of germinal center B-cells, ?GC-profile? has a significantly better survival than patients with tumors expressing genes normally induced during in vitro activation of peripheral blood



B-cells, ?ABC-profile?.



The first study (n=125) aimed to identify a protein pattern that could be used for discriminating germinal center derived (GC) and activated B-cell like (ABC)/non-GC DLBCL, using immunohistochemistry (IHC). BCL6, CD10 and CD40 were chosen as markers of a GC-phenotype, CD23 as a marker of pre/early GC-origin and CD138 as a marker of post-GC origin (i.e non-GC). No prognostically different subgroups, corresponding to GC or ABC (non-GC) could be identified. A new finding was the positive prognostic impact of CD23 and CD40 expression.



In the second study (n=125) the prognostic effect of CD40, but not CD23, was confirmed. The effect of CD40 effect could not be explained by association with the GC-phenotype or by an enhanced autologous tumour response, as detected by tumour infiltrating helper and cytotoxic T-lymphocytes. The prognostic effect of a GC versus non-GC phenotype according to Hans et al (Blood 2004) was confirmed.



The third study (n=122) identified the tissue microarray technique to be unreliable for immunohistochemical detection in GC vs. non-GC phenotypes, mostly due to difficulties interpreting BCL6 status.



In the fourth study tumours from patients with cured (n=24) versus primary chemotherapy-refractory DLBCL (n=13), were investigated with respect to gene expression profiles, using spotted 55K oligonucleotide arrays produced in Lund. The genes that most differed between chemotherapy sensitive and refractory tumours mainly coded for proteins expressed by cells in the tumour microenvironment, and not by the tumour cells themselves. Confirmative IHC showed that the frequency of tumour infiltrating lymphocytes, macrophages and reactive cells expressing proteolytic and pro-inflammatory proteins were higher in the chemo-sensitive cohort, indicating that the microenvironment has an impact on the response to chemotherapy in DLBCL. (Less)
Please use this url to cite or link to this publication:
author
opponent
  • dr.med. Grønbæk, Kirsten, Department of Hematology, Copenhagen University Hospital, Rigshospitalet
organization
publishing date
type
Thesis
publication status
published
subject
keywords
cancerology, Cytologi, Cytology, oncology, prognosis, Diffuse large B-cell lymphoma, CD40, gene expression profiling, tumour microenvionment, Medicin (människa och djur), Medicine (human and vertebrates), onkologi, cancer
pages
71 pages
publisher
Department of Oncology, Clinical Sciences, Lund University
defense location
the lecture hall, Barngatan 2, Lund University Hospital, Lund
defense date
2007-11-29 09:00
ISSN
1652-8220
ISBN
ISBN 978-91-85897-24-7
language
English
LU publication?
yes
id
b245b9fd-a2d3-42c4-8016-2ea50f2172ba (old id 599230)
date added to LUP
2007-11-13 08:21:51
date last changed
2016-09-19 08:44:58
@phdthesis{b245b9fd-a2d3-42c4-8016-2ea50f2172ba,
  abstract     = {Diffuse large B-cell lymphoma (DLBCL) is the most frequent lymphoma subtype. In Sweden 450 new cases are diagnosed annually. With modern anthracycline-containing chemotherapy DLBCL is potentially curable, with an estimated overall cure rate of approximately 50% for patients with advanced stage disease. Through molecular profiling of DLBCL the ?cell-of-origin concept? has been established: patients with tumours expressing genes characteristic of germinal center B-cells, ?GC-profile? has a significantly better survival than patients with tumors expressing genes normally induced during in vitro activation of peripheral blood<br/><br>
<br/><br>
B-cells, ?ABC-profile?.<br/><br>
<br/><br>
The first study (n=125) aimed to identify a protein pattern that could be used for discriminating germinal center derived (GC) and activated B-cell like (ABC)/non-GC DLBCL, using immunohistochemistry (IHC). BCL6, CD10 and CD40 were chosen as markers of a GC-phenotype, CD23 as a marker of pre/early GC-origin and CD138 as a marker of post-GC origin (i.e non-GC). No prognostically different subgroups, corresponding to GC or ABC (non-GC) could be identified. A new finding was the positive prognostic impact of CD23 and CD40 expression.<br/><br>
<br/><br>
In the second study (n=125) the prognostic effect of CD40, but not CD23, was confirmed. The effect of CD40 effect could not be explained by association with the GC-phenotype or by an enhanced autologous tumour response, as detected by tumour infiltrating helper and cytotoxic T-lymphocytes. The prognostic effect of a GC versus non-GC phenotype according to Hans et al (Blood 2004) was confirmed.<br/><br>
<br/><br>
The third study (n=122) identified the tissue microarray technique to be unreliable for immunohistochemical detection in GC vs. non-GC phenotypes, mostly due to difficulties interpreting BCL6 status.<br/><br>
<br/><br>
In the fourth study tumours from patients with cured (n=24) versus primary chemotherapy-refractory DLBCL (n=13), were investigated with respect to gene expression profiles, using spotted 55K oligonucleotide arrays produced in Lund. The genes that most differed between chemotherapy sensitive and refractory tumours mainly coded for proteins expressed by cells in the tumour microenvironment, and not by the tumour cells themselves. Confirmative IHC showed that the frequency of tumour infiltrating lymphocytes, macrophages and reactive cells expressing proteolytic and pro-inflammatory proteins were higher in the chemo-sensitive cohort, indicating that the microenvironment has an impact on the response to chemotherapy in DLBCL.},
  author       = {Linderoth, Johan},
  isbn         = {ISBN 978-91-85897-24-7},
  issn         = {1652-8220},
  keyword      = {cancerology,Cytologi,Cytology,oncology,prognosis,Diffuse large B-cell lymphoma,CD40,gene expression profiling,tumour microenvionment,Medicin (människa och djur),Medicine (human and vertebrates),onkologi,cancer},
  language     = {eng},
  pages        = {71},
  publisher    = {Department of Oncology, Clinical Sciences, Lund University},
  school       = {Lund University},
  title        = {Diffuse large B-cell lymphoma - tumour characteristics on RNA and protein level associated with prognosis},
  year         = {2007},
}