The association between CD99 and LMP-1 expression in nasopharyngeal carcinoma
Aim: To characterize the roles of LMP-1 and CD99 in nasopharyngeal carcinogenesis, we undertook this pilot study of LMP-1 and CD99 expressions in nasopharyngeal cancer (NPC). Materials and Method: 40 NPC tissue samples were grouped according to the WHO classification. Immunohistochemical studies wer...
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Інститут експериментальної патології, онкології і радіобіології ім. Р.Є. Кавецького НАН України
2006
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| Цитувати: | The association between CD99 and LMP-1 expression in nasopharyngeal carcinoma / H.-S. Kim, J.-S. Kim, J.-T. Park, M.-C. Lee, S.-W. Juhng, J.-H. Cho, C.-S. Park // Experimental Oncology. — 2006. — Т. 28, № 1. — С. 40-43. — Бібліогр.: 18 назв. — англ. |
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irk-123456789-1341582018-06-13T03:03:36Z The association between CD99 and LMP-1 expression in nasopharyngeal carcinoma Kim, H.-S. Kim, J.-S. Park, J.-T. Lee, M.-C. Juhng, S.-W. Cho, J.-H. Park, C.-S. Original contributions Aim: To characterize the roles of LMP-1 and CD99 in nasopharyngeal carcinogenesis, we undertook this pilot study of LMP-1 and CD99 expressions in nasopharyngeal cancer (NPC). Materials and Method: 40 NPC tissue samples were grouped according to the WHO classification. Immunohistochemical studies were performed using monoclonal antibodies against EBV latent membrane protein 1 (LMP-1) and CD99 protein. In addition, CD99 expression was evaluated in 10 samples of non-neoplastic nasopharyngeal epithelium. Results: LMP-1 was detected in 12 of the 40 (30.0%) cases and its expression was found to be confined to epithelial tumor cells. WHO type I NPC samples were completely negative for LMP-1, whereas WHO type III NPC samples showed highest expression. Interestingly, CD99 was expressed in all of the non-neoplastic nasopharyngeal epithelium samples along the cytoplasmic border. CD99 expression was noted in NPC tumor cells (5 of the 40 cases, 12.5%) and in surrounding lymphoid stroma (23 of the 40 cases, 57.5%), but was not expressed in WHO type I NPC. In the 12 LMP-1 positive cases, 9 cases (75.0%) were CD99 negative, and 3 cases (25.5%) were CD99 positive. There was a statistical significance between LMP-1 and CD99 expression in lymphoid stroma. Conclusion: Our results suggest that the LMP-1 induced down-regulation of the CD99 pathway is important in nasopharyngeal carcinogenesis, and that the expression of CD99 in lymphoid stroma may regulate immune response to NPC. Цель: изучить роль экспрессии латентного мембранного белка-1 (LMP-1) EBV и CD99 при развитии карциномы носоглотки (КНГ). Материалы и методы: в соответствии с классификацией ВОЗ 40 образцов КНГ были отнесены к типам I, II, III. Иммуногистохимический анализ проводили с использованием моноклональных антител против LMP-1 и CD99. Уровень экспрессии CD99 также был определен в 10 образцах нетрансформированного эпителия носоглотки. Результаты: экспрессия белка LMP-1 была выявлена в 12 из 40 образцов КНГ (30%) только в эпителиальных клетках опухоли. В КНГ I типа все образцы были негативными по экспрессии LMP-1, а в КНГ III типа была обнаружена самая высокая степень экспрессии. Интересно, что экспрессия CD99 была выявлена во всех контрольных образцах эпителия носоглотки по краю цитоплазмы. Ее также наблюдали в опухолевых клетках (в 12,5 образцов КНГ) и в окружающей лимфоидной строме (57,5% образцов КНГ), но не выявляли в КНГ І типа. Среди 12 LMP-1 позитивных образцов было выявлено 9 CD99 негативных (75,%) и 3 — CD99 позитивных (25,5%). Также наблюдались статистически значимые различия между экспрессией LMP-1 и CD99 в лимфоидной строме. Выводы:LMP-1 индуцирует подавление каскада CD99, выполняющего важную роль в образовании опухолей носоглотки. Экспрессия CD99 в лимфоидной строме может регулировать иммунную реакцию на КНГ. 2006 Article The association between CD99 and LMP-1 expression in nasopharyngeal carcinoma / H.-S. Kim, J.-S. Kim, J.-T. Park, M.-C. Lee, S.-W. Juhng, J.-H. Cho, C.-S. Park // Experimental Oncology. — 2006. — Т. 28, № 1. — С. 40-43. — Бібліогр.: 18 назв. — англ. 1812-9269 http://dspace.nbuv.gov.ua/handle/123456789/134158 en Experimental Oncology Інститут експериментальної патології, онкології і радіобіології ім. Р.Є. Кавецького НАН України |
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English |
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Original contributions Original contributions |
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Original contributions Original contributions Kim, H.-S. Kim, J.-S. Park, J.-T. Lee, M.-C. Juhng, S.-W. Cho, J.-H. Park, C.-S. The association between CD99 and LMP-1 expression in nasopharyngeal carcinoma Experimental Oncology |
| description |
Aim: To characterize the roles of LMP-1 and CD99 in nasopharyngeal carcinogenesis, we undertook this pilot study of LMP-1 and CD99 expressions in nasopharyngeal cancer (NPC). Materials and Method: 40 NPC tissue samples were grouped according to the WHO classification. Immunohistochemical studies were performed using monoclonal antibodies against EBV latent membrane protein 1 (LMP-1) and CD99 protein. In addition, CD99 expression was evaluated in 10 samples of non-neoplastic nasopharyngeal epithelium. Results: LMP-1 was detected in 12 of the 40 (30.0%) cases and its expression was found to be confined to epithelial tumor cells. WHO type I NPC samples were completely negative for LMP-1, whereas WHO type III NPC samples showed highest expression. Interestingly, CD99 was expressed in all of the non-neoplastic nasopharyngeal epithelium samples along the cytoplasmic border. CD99 expression was noted in NPC tumor cells (5 of the 40 cases, 12.5%) and in surrounding lymphoid stroma (23 of the 40 cases, 57.5%), but was not expressed in WHO type I NPC. In the 12 LMP-1 positive cases, 9 cases (75.0%) were CD99 negative, and 3 cases (25.5%) were CD99 positive. There was a statistical significance between LMP-1 and CD99 expression in lymphoid stroma. Conclusion: Our results suggest that the LMP-1 induced down-regulation of the CD99 pathway is important in nasopharyngeal carcinogenesis, and that the expression of CD99 in lymphoid stroma may regulate immune response to NPC. |
| format |
Article |
| author |
Kim, H.-S. Kim, J.-S. Park, J.-T. Lee, M.-C. Juhng, S.-W. Cho, J.-H. Park, C.-S. |
| author_facet |
Kim, H.-S. Kim, J.-S. Park, J.-T. Lee, M.-C. Juhng, S.-W. Cho, J.-H. Park, C.-S. |
| author_sort |
Kim, H.-S. |
| title |
The association between CD99 and LMP-1 expression in nasopharyngeal carcinoma |
| title_short |
The association between CD99 and LMP-1 expression in nasopharyngeal carcinoma |
| title_full |
The association between CD99 and LMP-1 expression in nasopharyngeal carcinoma |
| title_fullStr |
The association between CD99 and LMP-1 expression in nasopharyngeal carcinoma |
| title_full_unstemmed |
The association between CD99 and LMP-1 expression in nasopharyngeal carcinoma |
| title_sort |
association between cd99 and lmp-1 expression in nasopharyngeal carcinoma |
| publisher |
Інститут експериментальної патології, онкології і радіобіології ім. Р.Є. Кавецького НАН України |
| publishDate |
2006 |
| topic_facet |
Original contributions |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/134158 |
| citation_txt |
The association between CD99 and LMP-1 expression in nasopharyngeal carcinoma /
H.-S. Kim, J.-S. Kim, J.-T. Park, M.-C. Lee, S.-W. Juhng, J.-H. Cho, C.-S. Park // Experimental Oncology. — 2006. — Т. 28, № 1. — С. 40-43. — Бібліогр.: 18 назв. — англ. |
| series |
Experimental Oncology |
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2025-07-09T20:25:25Z |
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2025-07-09T20:25:25Z |
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| fulltext |
40 Experimental Oncology 28, 40–43, 2006 (March)
The Epstein-Barr virus (EBV) is a γ herpes virus
that infects more than 90% of the human population,
although the majority of carriers remain asymptomatic.
EBV infection is associated with nasopharyngeal car-
cinoma (NPC) and Hodgkin lymphoma (HL) [1].
The WHO classification of nasopharyngeal carci-
nomas distinguishes two major types, i.e., squamous
cell carcinoma and non-keratinizing carcinoma, the
latter of which includes undifferentiated carcinoma
[2].Although the association between non-keratiniz-
ing NPC (particularly of the undifferentiated subtype)
and EBV is well established, NPC oncogenesis is not
a simply consequence of EBV infection.
LMP-1 is the major transforming protein of EBV and
behaves as a classical oncogene. LMP-1 is an integral
membrane protein of 63 kDa, and can be subdivided into
three domains [3]. Its two distinct functional domains, re-
ferred to as C-terminal activation regions 1 and 2 (CTAR1
and CTAR2), were identified because of their ability to
activate the NF-κB transcription factor pathway [3].
The consequences of NF-κB activation are numer-
ous and include the upregulation of anti-apoptotic
gene products and the downregulation of cell surface
molecules CD99. In NPC cells, LMP-1 induces TRAF1
expression and promotes its anti-apoptosis activity via
the NF-κB signaling pathway, and thus suppresses
apoptosis in NPC cells [4].
CD99 is a strongly sialoglycosylated 32 kDa trans-
membrane protein [5] and is involved in multifacto-
rial cellular events, such as cell-cell adhesion during
hematopoietic cell differentiation, the apoptosis of
immature thymocytes and neuronal cells, and T-cell
activation [6, 7]. NPC and Hodgkin lymphoma, es-
pecially Reed—Sternberg cells (HRS) share several
features that warrant closer examination [8]. Kim et
al. [9] reported that HRS cells from the lymph nodes
of HL patients, consistently lack CD99 surface ex-
pression. Moreover, induced LMP-1 expression has
been demonstrated to directly down-regulate CD99
in B-cell lines at the transcriptional level via the NF-κB
pathway [10, 11]. This finding possibly indicates a role
for the LMP-1 induced down regulation of CD99 in the
generation of HRS-like cells. By comparison, little is
known about NPC in this respect.
The aim of this study was to evaluate the expressions
of LMP-1 and CD99 in NPC and to search for correla-
tions between these expressions and tumor growth.
Materials and Methods
Patients and specimens. A review of the H&E
sections of 40 patients revealed 5 squamous cell car-
cinomas (SCCs, WHO type I), 20 non-keratinizing car-
cinomas (NKCs, WHO type II), and 15 undifferentiated
carcinomas (UCs, WHO type III). There were 28 men
and 12 women (M : W=2.3 : 1), and patient ages ranged
from 18 to 80 years (mean age 52.1 years). NPC di-
agnoses were confirmed by nasopharyngeal biopsy
at the Department of Pathology, Chonnam National
University Hospital.
Immunohistochemistry. We reviewed the hema-
toxylin and eosin stained slides of all cases, and then
selected well preserved tissue blocks of formalin-fixed,
paraffin-embedded samples. The immunohistochemi-
cal analysis included monoclonal antibody for LMP-1
(DAKO, clones CS1-4, CA, USA: dilution 1 : 400), and
CD99 (DAKO, clones 12E7, CA, USA: dilution 1 : 50). Im-
munostaining was performed using the routine avidin-
the association between cd99 and lMP-1 exPression
in nasoPharyngeal carcinoMa
H.-S. Kim1, J.-S. Kim1, J.-T. Park1, M.-C. Lee1, S.-W. Juhng1, J.-H. Cho 2, C.-S. Park 1,*
1Department of Pathology, Chonnam National University Medical School, Gwangju, Korea
2Department of Otolaryngology, Konkuk University Medical School, Seoul, Korea
Aim: To characterize the roles of LMP-1 and CD99 in nasopharyngeal carcinogenesis, we undertook this pilot study of LMP-1
and CD99 expressions in nasopharyngeal cancer (NPC). Materials and Method: 40 NPC tissue samples were grouped according to
the WHO classification. Immunohistochemical studies were performed using monoclonal antibodies against EBV latent membrane
protein 1 (LMP-1) and CD99 protein. In addition, CD99 expression was evaluated in 10 samples of non-neoplastic nasopharyngeal
epithelium. Results: LMP-1 was detected in 12 of the 40 (30.0%) cases and its expression was found to be confined to epithelial
tumor cells. WHO type I NPC samples were completely negative for LMP-1, whereas WHO type III NPC samples showed highest
expression. Interestingly, CD99 was expressed in all of the non-neoplastic nasopharyngeal epithelium samples along the cytoplasmic
border. CD99 expression was noted in NPC tumor cells (5 of the 40 cases, 12.5%) and in surrounding lymphoid stroma (23 of
the 40 cases, 57.5%), but was not expressed in WHO type I NPC. In the 12 LMP-1 positive cases, 9 cases (75.0%) were CD99
negative, and 3 cases (25.5%) were CD99 positive. There was a statistical significance between LMP-1 and CD99 expression in
lymphoid stroma. Conclusion: Our results suggest that the LMP-1 induced down-regulation of the CD99 pathway is important in
nasopharyngeal carcinogenesis, and that the expression of CD99 in lymphoid stroma may regulate immune response to NPC.
Key Words: Epstein—Barr virus, latent membrane protein-1, CD99, nasopharyngeal carcinoma, Hodgkin lymphoma.
Received: November 28, 2005.
*Correspondence: Fax: +82-62-225-0480
E-mail: daniel5438@daum.net
Abbreviations used: EBV — Epstein—Barr virus; LMP-1 — latent
membrane protein-1; HL — Hodgkin lymphoma; HRS cell —
Hodgkin Reed—Sternberg cell; NPC — nasopharyngeal carcinoma.
Exp Oncol 2006
28, 1, 40–43
Experimental Oncology 28, 40–43, 2006 (March) 41
biotin complex (ABC) method. Briefly, representative
paraffin blocks were consecutively sectioned at 4µm
and immunostainusing a Microprobe Immuno/DNA
stainer (Fisher Scientific, CA, USA). Sections were de-
paraffinized in xylene, and treated with 0.3% hydrogen
peroxide in methanol for 20 min to block endogeneous
peroxidase activity. For LMP-1 and CD99 immunostain-
ing, sections were microwaved in citrate-phosphate
buffer (pH 6.0) once, and then incubated with anti-
bodies at room-temperature for 1 h. Anti-mouse im-
munoglobulin G (Sigma, St. Louis, MO, USA) labeled
with biotin was used as a secondary antibody to detect
primary antibodies, and was applied by incubation for
7 min at 45 °C. The streptavidin-horseradish peroxidase
(Research Genetics, USA) detection system used to
visualize capillary channels, by incubation for 10 min
at 45 °C. After drainage, tissue sections were reacted
with 0.02% diaminobenzidine as chromogen. They were
then counterstained with hematoxylin and mounted in
Universal Mount medium (Research Genetics, USA).
Cortical thymus tissue was used as positive control for
CD99 staining. Negative controls were treated similarly
with the exception of primary antibodies.
Evaluation of immunohistochemical results. All
immunostained slides were evaluated independently
by two observers, unaware of background information,
who both performed evaluations in duplicate. Appro-
priate positive and negative controls were prepared in
the same fashion. Cytoplasmic and/or membranous
staining patterns were considered positive for LMP-1.
In addition, staining in the Golgi region was also con-
sidered positive for LMP-1. However, for CD99 only
membranous staining was considered positive. Positive
cell frequencies were evaluated semi-quantitatively
and are expressed as ratios of positive-stained tumor
cells versus the total tumor cell population. They were
graded from 0 to +3 as follows: 0 = no tumor cells, +1 =
less than 25% tumor cells, +2 = 25% to 50% tumor cells,
and +3 = greater than 50% tumor cells. The intensity of
staining was not graded, and any expression of LMP-1
or CD99 was classified as positive.
Statistical analysis. Statistical analysis was per-
formed using SPSS for Windows, version 10.0.1(SPSS
Inc, USA). Results were statistically evaluated using
the Chi-square test or the Mann Whitney-U test, as
modified by Yates. A significance level of 0.05 was
used for all statistical tests.
results
LMP-1 expression in NPC samples. In order to
identify EBV-encoded LMP-1 expression in NPC, immu-
nostaining for LMP-1 was performed using CS1-4 mono-
clonal antibody by the ABC method. A dark red color in
the cell membrane and cytoplasm, especially in Golgi
areas, was considered as a positive reaction. LMP-1 was
detected only in tumor cells; infiltrating lymphocytes and
stroma were unstained (Fig. 1). Moreover, staining inten-
sities varied from cell to cell. In infiltrative lymphocytes
and stroma, LMP-1 was completely negative. LMP-1
expression was most frequently positive in WHO type III
than in WHO types I and II, and this type-associated dif-
ference was significant (p = 0.034, Table 1).
Fig. 1. Immunoreactivity for LMP-1 in WHO type II nasopha-
ryngeal carcinoma. Tumor cells exhibited cytoplasm and Golgi
apparatus focally positive immunoreactivity. The lymphocytes
surrounding the tumor cells were negative (LMP-1, X 400)
Table 1. Distribution of LMP-1 expression in CD99 in lymphoid stroma/tu-
mor tissue according to the positive frequency
Localization of ex-
pression
LMP-1 p valueGrade Negative Positive Total
CD99 in lymphoid
stroma
Negative 14 3 17
0.021Positive 14 9 23
Total 28 12 40
CD99 in epithelial
tumor cells
Negative 26 9 35
0.294Positive 2 3 5
Total 28 12 40
Table 2. Distribution of LMP-1, CD99, and bcl-2 expression according to
the histologic subtypes
Expression of the marker SCC NKC UC Total p value
LMP-1 0/5 5/20 7/15 12/40 0.034
CD99 in lymphoid stroma 0/5 11/20 11/15 23/40 0.440
CD99 in tumor 0/5 4/20 1/15 5/40 0.720
Notes: SCC — squamous cell carcinoma, WHO type I; NKC — non-keratinizing
carcinoma, WHO type II; UC— undifferentiated carcinoma, WHO type III
cd99 expression in non-neoplastic nasopha-
ryngeal epithelium and nPc samples. Initially, we
evaluated CD99 immunostaining in the 10 non-neoplastic
nasopharyngeal tissue samples. Some of these samples
were obtained from anterior and posterior nasopha-
ryngeal walls lined by stratified squamous epithelium,
whereas others were from posterior nares or the roof of
the posterior wall lined with ciliated respiratory-type co-
lumnar epithelium. All samples showed CD99 expression
along nasopharyngeal epithelial cytoplasmic borders and
in some lymphocytes in adjacent areas (Fig. 2).
We then evaluated CD99 immunostaining in the
NPC samples, where CD99 was more frequently
expressed in surrounding lymphoid stroma (23 of 40
cases, 57.5%, Fig. 3, a, Table 1) than in epithelial tu-
mor cells (5 of 40 cases, 12.5%, Fig. 3, b). According
to WHO types, CD99 expression in lymphoid stroma
was highest in WHO type III (11 of 15 cases, 73.3%),
and was completely negative in WHO type I. Moreover,
the staining intensity of CD99 was stronger in infiltrat-
ing lymphocytes and stroma than in tumor cells. No
evident correlation was observed between CD99 ex-
pression in stroma or tumor cells and WHO histologic
classification (Table 1). However, a significant positive
correlation was observed between LMP-1 and CD99
expressions in lymphoid stroma (Pearson correlation
42 Experimental Oncology 28, 40–43, 2006 (March)
coefficient = 0.298, p = 0.021, Table 2). And, in patients
with positive CD99 expression in epithelial tumor cells
(5 of the 40 cases), LMP-1 was negative in 2 cases and
positive in 3 cases, whereas in patients with positive
LMP-1 expression, CD99 was negative in 9 of 12 cases
(75.0%), and positive in 3 of 12 cases (25.5%).
Fig. 2. CD99 expression in non-neoplastic nasopharyngeal mu-
cosa. All cases showed CD99 expression along the cytoplasmic
borders of nasopharyngeal epithelium and in some lymphocytes
and vascular endothelial cells in adjacent areas
Fig. 3, a. Strong CD99 immunostaining in WHO type III naso-
pharyngeal carcinoma. This pattern is similar to that shown by
Ewing’s sarcoma and primitive neuroectodermal tumor, which
also show membranous accentuation (CD99, X 400)
Fig. 3, b. Immunoreactivity for CD99 in WHO type II nasopharyn-
geal carcinoma. Tumor cells exhibited negative immunoreactivity,
but lymphocytes surrounding tumor nests were strongly positive
(CD99, × 400)
discussion
LMP-1 has a significant effect on epithelial cell
growth, and it inhibits the differentiation and induces
the morphologic transformation of some cell lines. In
this study, in order to identify EBV-encoded LMP-1
expression in NPC, immunostaining of LMP-1 was
performed using CS1-4 monoclonal antibody by the
ABC method. Of the 40 NPC samples, 12 (30.0%)
showed LMP-1 expression confined to epithelial tumor
cells, which is consistent with the observation that viral
DNA is detectable in malignant epithelial cells rather
than in the abundant infiltrating lymphoid cells [12].
LMP-1 has been detected in less than 50% of NPC
using several different monoclonal antibodies [13, 14].
However, these antibodies did not recognize all forms
of LMP-1, thus the reported rate of LMP detection may
represent an underestimation [15]. Moreover, it is pos-
sible that in some tumors LMP-1 is expressed at below
the level of detection or that as a cancer progresses
the expression of viral protein is no longer required
as other genetic changes substitute for the effects of
viral proteins [15].
Kim et al.[9] reported that HRS cells from the lymph
nodes of HL patients consistently lack of CD99 surface
expression, and enhanced LMP-1 expression has been
shown to directly down-regulate CD99 in B cell lines
at the transcriptional level via the NF-κB pathway. In
contrast, in the present study, LMP-1 was found to
be positive in 3 of 5 NPC samples expressing CD99.
In terms of LMP-1 immunopositivity, of the 12 LMP-1
positive NPC samples, CD99 was negative in 9 cases
(75.0%) and positive in 3 (25.0%). Our findings, and
those of previous reports [9], indicate that LMP-1 may
induce the down-regulation of CD99 and play an im-
portant role in nasopharyngeal carcinogenesis. In view
of the finding that CD99-independent LMP-1 induced
pathways generate H-RS cells in a synergistic way [16],
our finding of LMP-1+CD99+ NPC cells indicates the
need for further studies to elucidate the role of CD99
in NPC carcinogenesis.
Infiltrating lymphocytes and lymphoid stroma are
characteristic histopathologic features of WHO type III
NPC. Lymphoid stroma is predominantly composed of
T cells, and CD4 and CD8 expressing cells in variable
proportions [17]. In the present study, a considerable
number of surrounding lymphocytes showed strong
reactivity for CD99, and a significant positive cor-
relation was observed between LMP-1 expression in
tumor cells and CD99 expression in lymphoid stroma
(Pearson correlation coefficient = 0.298, p = 0.021,
Table 2). CD99 is present on all human T- cells, but has
no clear biologic function [5, 18]. Studies on mature
peripheral T cells have shown that co-ligation of CD99
and CD3 may enhance the expression of CD25, CD69,
and CD40 ligand, induce T-cell proliferation, and also
promote the production of TNF-α and IFN-γ [7]. These
findings suggest that CD99 may contribute to T-cell
activation in NPC microenvironment and promote com-
munication between tumor cells and tumor-infiltrating
T lymphocytes.
Experimental Oncology 28, 40–43, 2006 (March) 43
ВзаимосВязь между экспрессией cd99 и lMP-1
В карциноме носоглотки
Цель: изучить роль экспрессии латентного мембранного белка-1 (LMP-1) EBV и CD99 при развитии карциномы носоглотки
(КНГ). Материалы и методы: в соответствии с классификацией ВОЗ 40 образцов КНГ были отнесены к типам I, II, III.
Иммуногистохимический анализ проводили с использованием моноклональных антител против LMP-1 и CD99. Уровень
экспрессии CD99 также был определен в 10 образцах нетрансформированного эпителия носоглотки. Результаты: экспрессия
белка LMP-1 была выявлена в 12 из 40 образцов КНГ (30%) только в эпителиальных клетках опухоли. В КНГ I типа все
образцы были негативными по экспрессии LMP-1, а в КНГ III типа была обнаружена самая высокая степень экспрессии.
Интересно, что экспрессия CD99 была выявлена во всех контрольных образцах эпителия носоглотки по краю цитоплазмы.
Ее также наблюдали в опухолевых клетках (в 12,5 образцов КНГ) и в окружающей лимфоидной строме (57,5% образцов
КНГ), но не выявляли в КНГ І типа. Среди 12 LMP-1 позитивных образцов было выявлено 9 CD99 негативных (75,%) и
3 — CD99 позитивных (25,5%). Также наблюдались статистически значимые различия между экспрессией LMP-1 и CD99
в лимфоидной строме. Выводы:LMP-1 индуцирует подавление каскада CD99, выполняющего важную роль в образовании
опухолей носоглотки. Экспрессия CD99 в лимфоидной строме может регулировать иммунную реакцию на КНГ.
Ключевые слова: вирус Эпштейна—Барр, латентный мембранный белок-1, CD99, карцинома носоглотки, лимфома
Ходжкина.
Copyright © Experimental Oncology, 2006
In conclusion, our results suggest that LMP-1 induc-
es the down-regulation of CD99, and that this might be
an important step in nasopharyngeal carcinogenesis, as
shown in the HRS synthesis in HL. Moreover, our find-
ings show that CD99 expression in lymphoid stroma is
influenced by the presence of LMP-1.
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