Structure and expression of the cyclin A gene in human primary liver cancer. Correlation with flow cytometric parameters.
OBJECTIVE
The cyclin A gene plays an important role in both the S and G2-M phases of the cell cycle, and has been identified at a site of hepatitis B virus DNA integration in a human liver cancer. We analyzed tumorous and non-tumorous samples from patients with primary liver cancer to determine whether a) the cyclin A gene is rearranged in liver tumors and b) the cyclin A transcript level correlates with the percentage of proliferating cells.


METHODS
Samples from 43 patients were analyzed by Southern blot. Cyclin A RNA accumulation was evaluated in 18 cases by slot blot and correlated with the percentage of cells in S plus G2-M phases defined by flow cytometry.


RESULTS
No rearrangement of the cyclin A gene was found in tumorous compared to non-tumorous tissue. A very strong positive correlation was found between the cyclin A RNA level and the cumulative percentage of cells in S plus G2-M phases (r = 0.99; p < 0.0001).


CONCLUSIONS
This in vivo study shows that the expression of cyclin A RNA correlates with the percentage of proliferating cells in primary liver cancer. Thus, cyclin A is a new potential liver tumor cell proliferation index.
INSERM U370, CHU Necker, Paris, France.
P
P
Paterlini
J F
JF
Flejou
M S
MS
De Mitri
E
E
Pisi
D
D
Franco
C
C
Bréchot
D015139:Blotting, Southern; D006528:Carcinoma, Hepatocellular / Q000235:genetics* / Q000473:pathology*; D002453:Cell Cycle / Q000235:genetics; D002455:Cell Division / Q000235:genetics; D016213:Cyclins / Q000032:analysis / Q000235:genetics*; D004273:DNA, Neoplasm / Q000032:analysis / Q000235:genetics*; D005434:Flow Cytometry; D006801:Humans; D008099:Liver / Q000737:chemistry / Q000473:pathology; D008113:Liver Neoplasms / Q000235:genetics* / Q000473:pathology*; D012334:RNA, Neoplasm / Q000032:analysis / Q000235:genetics
D016213:Cyclins; D004273:DNA, Neoplasm; D012334:RNA, Neoplasm