NF-kappaB signalling proteins p50/p105, p52/p100, RelA, and IKKepsilon are over-expressed in oesophageal squamous cell carcinomas.
OBJECTIVE
Nuclear factor-kappa B (NF-kappaB) activation has been recognised as an important mechanism in the development of cancers. However, expression status of NF-kappaB-related proteins in oesophageal squamous cell carcinoma (ESCC) tissues is largely unknown. In this study, we analysed expressions of NF-kappaB members (p50/105, p52/p100 and RelA) and IKKepsilon in ESCC tissues.


METHODS
We analysed the expression of p50/105, p52/p100, RelA and IKKepsilon in 58 ESCC patients' tissues by immunohistochemistry using a tissue microarray (TMA) method.


RESULTS
Normal oesophageal squamous cells expressed p50/105, p52/p100 and RelA in 5%, 79% and 10% of the tissues in cytoplasm, respectively; however, only p52/p100 was expressed in the nuclei (12%). The cancer tissues expressed p50/105, p52/p100 and RelA in 93%, 95% and 95% in cytoplasm and/or nuclei, respectively. Nuclear immunostainings of NF-kappaB members p50/105, p52/p100 and RelA, which are considered activation of NF-kappaB signalling, were observed in 34%, 60% and 26% of the cancers, respectively. IKKepsilon is expressed in cytoplasm in 50% of the normal squamous tissues and 84% of the cancer tissues. However, none of the expression of p50/105, p52/p100, RelA or IKKepsilon was associated with pathological characteristics, including differentiation, depth of invasion and TNM stage.


CONCLUSIONS
The increased nuclear expressions of p50/105, p52/p100 and RelA as well as increased cytoplasmic expression of IKKepsilon in the ESCC tissues compared to the normal squamous cells suggested that over-expression of these proteins may be related to activation of the NF-kappaB pathway and might play a role in the development of ESCC.
Kang
Mi Ran
MR
Department of Pathology, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Kim
Min Seop
MS
Kim
Sung Soo
SS
Ahn
Chang Hyeok
CH
Yoo
Nam Jin
NJ
Lee
Sug Hyung
SH
D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology; D002467:Cell Nucleus / Q000378:metabolism / Q000473:pathology; D003593:Cytoplasm / Q000378:metabolism / Q000473:pathology; D004938:Esophageal Neoplasms / Q000378:metabolism* / Q000473:pathology; D004947:Esophagus / Q000378:metabolism / Q000473:pathology; D019085:Fluorescent Antibody Technique, Direct; D006801:Humans; D051550:I-kappa B Kinase / Q000378:metabolism*; D007124:Immunoenzyme Techniques; D008875:Middle Aged; D052002:NF-kappa B p50 Subunit / Q000378:metabolism*; D052003:NF-kappa B p52 Subunit / Q000378:metabolism*; D009361:Neoplasm Invasiveness; D009363:Neoplasm Proteins / Q000378:metabolism; D015398:Signal Transduction; D046888:Tissue Array Analysis; D051996:Transcription Factor RelA / Q000378:metabolism*
D014408:Biomarkers, Tumor; D052002:NF-kappa B p50 Subunit; D052003:NF-kappa B p52 Subunit; D009363:Neoplasm Proteins; D051996:Transcription Factor RelA; D051550:I-kappa B Kinase