Expression of K+ channels in normal and cancerous human breast.
Potassium (K+) channels contribute to the regulation of cell proliferation and apoptosis and are also involved in tumor generation and malignant growth. Using immunohistochemical analysis, we investigated the expression of four K+ channels GIRK1 (G-Protein Inwardly Rectifying Potassium Channel 1), Ca2+-activated K channel (K Ca 1.1), voltage activated K+ channels (KV 1.1 and KV 1.3) and of the anti-apoptotic protein Bcl2 in normal and cancerous breast tissues and compared their expression with clinicopathological data. GIRK1 was overexpressed in carcinomatous tissues. In contrast, K V 1.1 and K V 1.3 were less expressed in cancerous tissue. The expression of Bcl-2 was similar in both tissues. As to the clinicopathological data, a correlation between K Ca 1.1 channel and estrogen receptor (ER) expression was observed. GIRK1 was overexpressed in breast carcinoma suggesting its involvement in proliferation and oncogenesis and its possible use as a putative pharmaceutical target. The correlation between K Ca 1.1 channel and ER suggests the involvement of this channel in proliferation. The loss of expression of the two channels K V 1.1 and K V 1.3 may correspond to their role in apoptosis.
Brevet
Marie
M
Laboratoire de Physiologie Cellulaire et Moléculaire, EA 2086, Faculté des Sciences, Amiens, France. brevet.marie@chu-amiens.fr
Ahidouch
Ahmed
A
Sevestre
Henri
H
Merviel
Philippe
P
El Hiani
Yassine
Y
Robbe
Micheline
M
Ouadid-Ahidouch
Halima
H
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism* / Q000556:secondary; D002452:Cell Count; D005260:Female; D019085:Fluorescent Antibody Technique, Direct; D051676:G Protein-Coupled Inwardly-Rectifying Potassium Channels / Q000378:metabolism; D006801:Humans; D007124:Immunoenzyme Techniques; D008875:Middle Aged; D009367:Neoplasm Staging; D015221:Potassium Channels / Q000378:metabolism*; D024681:Potassium Channels, Calcium-Activated / Q000378:metabolism; D024642:Potassium Channels, Voltage-Gated / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism
D014408:Biomarkers, Tumor; D051676:G Protein-Coupled Inwardly-Rectifying Potassium Channels; D015221:Potassium Channels; D024681:Potassium Channels, Calcium-Activated; D024642:Potassium Channels, Voltage-Gated; D019253:Proto-Oncogene Proteins c-bcl-2