Measures of tumor proliferative activity

Expression of the proliferating cell nuclear antigen and clinicopathological features in intracranial meningiomas

PC10, a monoclonal antibody (mAb) to proliferating cell nuclear antigen (PCNA) is known to show immunoreactivity in paraffin-embedded specimens. The authors present the relation between PCNA expression and clinicopathological features in 38 intracranial meningiomas. PCNA scores were obtained by immunohistochemical staining of the paraffin-embedded sections using a streptavidin-biotin immunoperoxidase method with PC10 mAb. Univariate analysis showed that high PC10 scores were associated with old age (> or = 50 years old), male, recurrent tumours, and meningothelial type. However, these high scores did not reach a statistical significance (P> 0.05). PC10 scores of the basal meningioma tended to be higher than that of the hemispheric meningioma (P< 0.05). The staining intensity of PCNA was also markedly increased in basal meningiomas. It is suggested that the proliferative potential is higher in basal meningiomas than in hemispheric meningiomas. Moreover, these results could reflect high recurrence and difficulty in management of the skull base meningiomas.

Locomotion and proliferation of glioblastoma cells in vitro: statistical evaluation of videomicroscopic observations

OBJECT

The motility and doubling of human glioblastoma cells were investigated by means of statistical evaluation of large sets of data obtained using computer-aided videomicroscopy.

METHODS

Data were obtained on cells in four established glioblastoma cell lines and also on primary tumor cells cultured from fresh surgical samples. Growth rates and cell cycle times were measured in individual microscopic fields. The averages of cell cycle time and the duplication time for the recorded cell populations were 26.2 +/- 5.6 hours and 38 +/- 4 hours, respectively. With these parameters, no significant differences among the cell lines were revealed. Also, there was no correlation in the cell cycle time of a parent cell and its progeny in any of the cultures. Statistical analysis of cell locomotion revealed an exponential distribution of cell velocities and strong fluctuations in individual cell velocities across time. The average velocity values ranged from 4.2 to 27.9 micro/hour. In spite of the uniform histopathological classification of the four tumors, each cell line produced by these tumors displayed distinct velocity distribution profiles and characteristic average velocity values. A comparison of recently established primary cultures with cell lines that had propagated multiple times indicated that cells derived from different tumors sustain their characteristic locomotor activity after several passages.

CONCLUSIONS

It can be inferred from the data that statistical evaluation of physical parameters of cell locomotion can provide additional tools for tumor diagnosis.

Expression of proliferating cell nuclear antigen (PCNA) and Ki-67 in soft tissue sarcoma. Is prognostic significance histotype-specific?

Abnormal patterns of proliferation characterize the behavior of many tumors. Proliferating cell nuclear antigen (PCNA) and Ki-67 are two cell cycle antigens which are expressed in proliferative states. Our study examines the prognostic value of these cell-cycle antigens in soft tissue sarcoma (STS). Paraffin-embedded primary tumor tissues from 185 patients (1980-92) were stained with the anti-PCNA antibody PC-10; 182 of these were stained with the antibody MIB-1 for Ki-67. Using PCNA (< or = 50; > 50%) and Ki-67 (< or = 10; > 10%) indices, we examined and compared metastasis-free survival (MFS) in a mixed-histotype group, as well as after subdivision into MFH and non-MFH groups. Fifty-seven patients developed metastases. The median follow-up for survivors was 6 (2-13) years. In the mixed series, the 2-year MFS for a PCNA index < or = 50 was 76%, and for an index > 50 56%. Survival predicted by Ki-67 index was comparable. PCNA index (but not Ki-67) strongly correlated with the incidence of metastasis in MFH tumors and predicted 2-year MFS of 81 vs 48%. In contrast, Ki-67 index (but not PCNA) strongly correlated with metastasis in non-MFH tumors and predicted 2-year MFS survival of 90 vs 45%. No correlation existed between PCNA and Ki-67 indices in the mixed histotype, MFH or non-MFH groups. In combination, a high PCNA and Ki-67 index correlated with poor survival, a high PCNA and lower Ki-67 index (or vice versa) with an intermediate survival, and low PCNA and Ki-67 indices with the best survival. The pattern of PCNA and Ki-67 expression raises the possibility of histotype specificity.

Analysis of proliferative grade in glial neoplasms using antibodies to the Ki-67 defined antigen and PCNA in formalin fixed, deparaffinized tissues

In an effort to optimize immunocytochemical methods to evaluate cell kinetics in brain tumors, we studied two newly-developed antibodies which react with formalin resistant epitopes of Proliferating Cellular Nuclear Antigen (PCNA) and Ki-67. These results were compared with standard flow cytometric cell cycle data from the same tumor specimens to determine if these methods correlate with each other, and whether retrospective analysis using these antibodies is feasible for cell kinetic analysis of brain tumors. Thirty-one specimens of glial tumors submitted for flow cytometry during 1992 were also reacted with antibodies to PCNA (PC-10) and Ki-67 (MIB-1). Flow cytometry scores for S-phase Fraction were compared with immunocytochemical scores for both antibodies, using an arbitrary rating of 1 (low, < 4%), 2 (intermediate, 4-6%), 3 (high, > 6%), and 1 (< 25% positive), 2 (26-75% positive), 3 (> 75% positive), respectively. MIB-1 results were found to correlate significantly with the S-phase fraction as determined by flow cytometry. The MIB-1 data showed a trend toward underestimating, i.e., lower scores, the proliferative index compared with flow cytometry. There was less of a correlation between PC-10 antibody scores and flow cytometry S-phase fraction, as PC-10 immunostaining typically overestimated the proliferative rate of brain tumors when compared with flow cytometry. There was an exact correlation between PC-10 and MIB-1 in only 4 cases, whereas in the remaining specimens, PC-10 results were always higher than MIB-1.(ABSTRACT TRUNCATED AT 250 WORDS)