Lack of prognostic significance of the pretreatment labeling and mitotic indices of marrow blasts in acute nonlymphocytic leukemia (ANLL)

Cytokinetic Studies in Acute Leukemia during Early Induction Therapy

The proliferative activity of bone marrow blasts was determined in 19 patients with acute leukemia during early induction therapy using in vitro tritiated thymidine (3H-TdR) cytoautoradiography and propidium iodide DNA flow cytofluorometry. Folloding 1-3 causes of treatment, the aliquot of bone marrow blasts in 9 patients, who later achieved remission or marrow aplasia, was reduced to a greater extent that of the remaining 10 patients who failed to respond. In the first group of patients, the 3H-TdR labeling index was increased by 259-653 % over the pretreatment value, whereas it was lower than 104 % of the pretreatment value in all but one unresponsive patient. Leukemic blast recruitment is conceivable. It might have facilitated remission by increasing the effectiveness of the antileukemic agents administered later.

Predictive value of statin, a G0-associated cell cycle protein, in childhood acute lymphoblastic leukemia

Blast cells of 71 children with newly diagnosed acute lymphoblastic leukemia (ALL) were examined with a novel monoclonal antibody (MAb), S-44, immunoreactive to statin, a nuclear protein specifically expressed in non-proliferating cells. The statin labeling index (LI) varied greatly from case to case and ranged from 0.3% to 86%, with a mean value of 10%. The degree of statin LI correlated inversely with the expression of Ki-67. When patients were subdivided according to whether the statin LI was higher or lower than the mean value, patients with higher statin LI did not respond to chemotherapy and survived for a shorter period of time. Our results suggest that labeling of statin with the S-44 MAb is a useful prognostic marker of the cytotoxic effects of anti-cancer drugs in patients with ALL.

Cell kinetics with in vivo bromodeoxyuridine assay, proliferating cell nuclear antigen expression, and flow cytometric analysis. Prognostic significance in acute nonlymphoblastic leukemia

BACKGROUND

The proliferative characteristics of acute nonlymphoblastic leukemia (ANLL) were studied in vivo, and data were correlated with response to chemotherapy and survival.

METHODS

Sixty-five patients with untreated ANLL and 15 patients with solid tumors and normal bone marrow (BM) received 250 mg/m2 of bromodeoxyuridine (BUdR); bivariate flow cytometric (FCM) analysis then was used to measure cell BUdR incorporation and DNA content to obtain a complete set of kinetic parameters (i.e., BM BUdR-labeling index, DNA-synthesis time, potential doubling time [Tpot], and cell production rate). The percentage of blasts with positive results for proliferating cell nuclear antigen (PCNA) also was obtained by FCM analysis on the same BM samples, and these kinetic parameters were derived specifically for the ANLL proliferating compartment (growth fraction). Induction therapy, consisting of vincristine, arabinosylcytosine, and daunomycin, was administered subsequently to the patients with ANLL.

RESULTS

Overall ANLL proliferative activity was lower than normal myelopoiesis, and a short Tpot was found to be a favorable factor for achieving complete remission (CR), the duration of CR, and survival. When the growth fraction was considered, however, ANLL proliferative activity was higher and more like that of normal BM. The kinetic differences detected in the PCNA-positive cells of patients with CR and no response and those with CR and survival durations above and below the median values for the entire series were highly significant in univariate analysis and retained a strong independent prognostic value when multivariate analysis was performed.

CONCLUSIONS

These data show the clinical feasibility of a detailed study of cell kinetics by means of new FCM-based techniques and reinforce the clinical value of pretreatment proliferative activity in ANLL.

Multidrug resistance in acute leukemia: a conserved physiologic function

Native resistance to conventional chemotherapy remains an important cause of treatment failure in the adult acute leukemias. Delineation of cellular mechanisms of drug resistance therefore represents a prerequisite to the development of more effective treatment strategies. The multidrug resistance (MDR) phenotype represents one such mechanism of resistance with direct clinical relevance. This phenotype occurs normally in certain mammalian tissues, and is detectable in tumor cell lines selected for resistance to naturally occurring antineoplastics. The mdr1 gene or its glycoprotein product, P-glycoprotein, is detected with high frequency in secondary acute myeloid leukemia (AML) and poor-risk subsets of acute lymphoblastic leukemia. In prospective studies in AML, MDR overexpression is an independent determinant of response to treatment and overall survival with conventional-dose induction regimens. Investigations of mdr1 regulation in normal hematopoietic elements has shown a pattern which corresponds to its regulation in acute leukemia, explaining the linkage of mdr1 to specific cellular phenotypes. Therapeutic trials are now in progress to test the ability of various MDR-reversal agents to restore chemotherapy sensitivity in high-risk acute leukemias.

Cell kinetics with in vivo bromodeoxyuridine and flow cytometry: clinical significance in acute non-lymphoblastic leukaemia

From 1986 to 1988, 54 consecutive previously untreated patients with acute non-lymphoblastic leukaemia (ANLL), median age 54 years, were treated for remission (CR) induction with vincristine and intravenous medium-dose cytarabine sequentially followed by daunomycin and infusion cytarabine. CR patients received intensive consolidation. Bone marrow blast kinetics was studied before therapy with in vivo bromodeoxyuridine and bivariate flow cytometry. CR rate was 70.2%, median CR was 13.2 months, responsive patient survival was 16.9 months and overall survival was 9.2 months. Besides lower median age, the 33 responsive patients also had shorter potential doubling time (Tpot) and greater cell production rate (PR) than the 14 unresponsive patients (mean values = 10.9 vs. 25.4 days, P less than 0.05, and 14.7 vs. 8.9 cells/100 cells/day, P less than 0.02, respectively), due to a higher mean labelling index (7.0 vs. 5.1%, P less than 0.05) and/or to a shorter mean DNA synthesis time (13.6 vs. 18.6 hours, P less than 0.05). Besides lower white blood cell count and bone marrow blast percentage, patients who experienced CR longer than 13.2 months had shorter Tpot (P less than 0.05) and a greater PR (P less than 0.02) than those who relapsed before this time. These data indicate that kinetic parameters have prognostic relevance in ANLL patients treated with sequential vincristine, cytarabine and daunomycin for inducing CR and with intensive consolidation after CR, a high proliferative activity being a favourable factor for both CR achievement and its duration.

5-bromodeoxyuridine (BUdR) quenching of acridine orange fluorescence distinguishes cycling and non-cycling normal and malignant bone marrow cells in vitro

Suppression of the green fluorescence of acridine orange by 5-bromodeoxyuridine incorporation into cellular DNA was measured by flow cytometry. Bone marrow cells from normal volunteers and patients with chronic myelogenous leukemia acute lymphocytic leukemia acute myelogenous leukemia and multiple myeloma were incubated with BUdR in vitro. By 24 h acridine orange stained cycling cells that had synthesized DNA in the presence of BUdR were differentiated from quiescent cells as a second peak with quenched green fluorescence (DNA). After 72 h in culture 11-65% of the G0/G1 cells from normal bone marrows and bone marrows with myeloid leukemia were identified as cycling in culture by the presence of a second peak with quenched green fluorescence. A greater percentage of cells with BUdR quenched AO fluorescence was associated of acridine orange was higher in the cycling cells that had synthesized DNA in the presence of BUdR than in the non-cycling G0/G1 cells. In one patient with AML there was quenching of the DNA fluorescence of the aneuploid population but not the diploid population indicating that the aneuploid leukemia cells were proliferating. In contrast in patients with multiple myeloma, the quenched fluorescence of the diploid cell population and not the aneuploid cells, indicated that the diploid cells were proliferating. The cells from patients with untreated ALL failed to proliferation prohibiting an in vivo assessment of growth. Although measurements of proliferation obtained by this method are clearly influenced by the cell's adaptation to culture, measurement of BUdR quenching of acridine orange fluorescence is technically feasible and can identify and allow characterization of the cycling population of cells.

Adult acute non-lymphoblastic leukaemia: reliability and prognostic significance of pretreatment bone marrow S-phase size determined by flow cytofluorometry

46 adult patients with non-lymphoblastic acute leukaemia (AnLL) had pretreatment proliferative activity of bone marrow (BM) blasts determined simultaneously with propidium iodide DNA flow cytofluorometry (as the percentage of cells with DNA content intermediate between the diploid and the tetraploid values, 2n-4n cell %) and in vitro tritiated thymidine cytoautoradiography (as the labelling index, LI). They were then treated with the same chemotherapy regimen, including 2-3 courses of sequential vincristine, arabinosylcytosine and adriamycin, for response induction, and monthly courses of different cytostatics for maintenance. Median 2n-4n cell % was 9.9 and median LI was 5.9. A close linear relationship (r = 0.913, p less than 0.001) between the two parameters was found. Patients having a 2n-4n cell % greater than 15.6 responded more often to chemotherapy than patients having a lower percentage (p less than 0.05) but also experienced a shorter duration of first response (p less than 0.05). Overall survival was longer in patients with 2n-4n cell % greater than 15.6 (p less than 0.02). Multiple regression analysis indicates that 2n-4n cell % is a statistically significant (p less than 0.05) independent factor correlating with duration of response in adult AnLL.

Pretreatment of cytokinetics in acute myelogenous leukemia. Age-related prognostic implications

To determine the clinical and biologic relevance of cellular kinetics in leukemia, DNA flow cytometric analysis was performed on bone marrow biopsy specimens from 148 previously untreated adult patients with acute myelogenous leukemia. The proportion of cells in synthesis, second growth, and mitosis (S + G2M) ranged from 4% to 33% with a median of 14%. The overall incidence of complete remission was not affected by the pretreatment cell cycle distribution. As in earlier studies, there was a marked decline in remission rate with advancing age from 73% for patients age less than or equal to 50 yr to 50% for those greater than 50 (P less than 0.01). Although not affecting remission induction overall, an increasing proportion of cells in S + G2M phase was favorable in patients under the age of 50 yr, but was associated with a progressive decline in remission rate in older patients (P = 0.01). This age-related divergent effect of cell cycle kinetics on initial response to therapy was confined to the less favorable subgroup of patients with karyotypic abnormalities, whereas patients with normal diploid cytogenetics had a consistently higher response rate regardless of proliferative activity. A positive correlation was also observed between percent of S + G2M cells and the proportion of diploid metaphases in young patients, contrasting with a negative correlation in the older age group. Our observations strongly suggest that the well-recognized prognostic effect of age on remission induction is not entirely host-mediated, but is at least partly an expression of disease-intrinsic differences between young and older patients.

Alteration of tumor cell kinetics by pulse total parenteral nutrition. Potential therapeutic implications

Previous work has demonstrated that substrate-induced alterations of tumor metabolism can be exploited to potentiate tumor response to cycle-specific chemotherapy (methotrexate, Adriamycin [doxorubicin] ). This study was performed to investigate the biologic mechanism responsible for this phenomenon by determining the effect of short-term total parenteral nutrition (TPN) on tumor cytokinetics. Forty-two female Lewis/Wistar rats with subcutaneous mammary tumor implants (AC-33) underwent superior vena caval cannulation, and were randomized to receive either TPN or normal saline intravenously. Animals receiving TPN were killed at 2, 6, 12, 24, and 48 hours after initiating TPN; control animals given normal saline were killed at 0, 24, and 48 hours after randomization. At the time animals were killed tumor cytokinetic analysis was performed by flow cytophotometry. The percentage of tumor cells in S-phase was significantly increased in animals after only 2 hours of TPN (55.5 +/- 9.1%) compared with the control group (43.7 +/- 7.7%) (P less than 0.01). The ratio of sensitive/resistant tumor cells to S-phase-specific chemotherapy was effectively increased in animals receiving adjuvant TPN (1.31 +/- 0.43) compared with control animals (0.80 +/- 0.25) (P less than 0.015). This alteration in tumor cytokinetics provides one explanation for the enhanced tumor response to cycle-specific chemotherapy previously observed with pulse TPN administration.

Cell kinetics in acute leukemia: a critical reevaluation based on new data

The current study was undertaken to compare biopsy and aspiration sampling techniques for reliable cell kinetic analysis in acute leukemia and to reevaluate the clinical significance of cell kinetic data in this disease. Ad 1: One hundred forty-three paired simultaneously taken marrow aspirates and Jamshidi biopsies from 61 patients with acute nonlymphocytic leukemia (ANLL) were compared by means of flow cytometry (FCM) for cellular DNA and RNA measurements, autoradiography for 3H-TdR labeling index and liquid scintillation counting for 3H-TdR uptake. Aspirates were found unreliable for pretreatment evaluation and for monitoring of drug induced cell kinetic perturbations due to contamination with peripheral blood. Aspiration should, therefore, be replaced by marrow biopsy which provides reliable sampling of bone marrow for cell kinetic studies. Ad 2: FCM S-phase index determined from biopsy material was not found predictive for therapeutic response in 43 patients with ANLL treated with two different induction regimens. In one of the two protocols, changes in FCM S-phase index after 48 hours continuous infusion of cytosine arabinoside correlated significantly with clinical response and nonresponse, respectively.

Epithelial cells kinetics. A review of methods of study and their application to oral mucosa in health and disease. Part B. Comparison of cell kinetics in normal and abnormal epithelia

In Part A, the techniques most commonly used to study epithelial cell kinetics and their suitability for use in man are reviewed. In Part B, the application of such methods to comparative studies of normal and abnormal oral epithelial of both man and experimental animals is examined. Claims regarding the possible prognostic value of LI's or MI's of biopsies of potentially or overtly malignant human oral lesions are also considered. Normal and abnormal kinetic data for other lining epithelia, e.g., skin, uterine cervix and gastrointestinal mucosa are assessed where they provide a better illustration of some of the problems arising in such comparative investigations. Finally, the present and likely future areas in which cell kinetic studies may provide a guide to expected tumour prognosis and optimum treatment are summarized.

Bone marrow biopsy instead of 'marrow juice' for cell kinetic analysis. Comparison of bone marrow biopsy and aspiration material

Since cell kinetic bone marrow studies have so far exclusively been carried out on aspiration material and have yielded inconsistent or even contradictory results, we investigated the adequacy and reliability of aspirates for cell kinetic analyses in comparison to biopsies. Paired samples of bone marrow (133) were taken simultaneously by aspiration and Jamshidi biopsy from 48 patients with acute leukemias and 67 patients with non-leukemic disorders. Cell kinetic analysis by (1) flow cytometry (FCM) of cellular DNA and RNA content, (2) autoradiography for [3H]TdR pulse labelling indices and (3) liquid scintillation counting of [3H]TdR uptake revealed significantly higher values in biopsies (p less than 0.001) exceeding the corresponding results from aspirates on average by factors of 1.65 for FCM S-phase index, 1.90 for G0/1 cells with high RNA content, 1.82 for [3H]TdR LI and 1.90 for [3H]TdR uptake. In more than 70% of all samples results from biopsies were 1.1-11.4 times higher, indicating that aspirates were equivalent to biopsies in fewer tan 30% of cases. Cell kinetic analysis in vitro blood/biopsy mixtures and measurements of DNA synthesis rate in corresponding aspirates and biopsies revealed that these discrepancies are due to the contamination of aspirates with non-proliferating nucleated blood cells. Biopsy, however, was found to provide representative and reproducible sampling of marrow for cell kinetic studies and should replace the presently used aspirate already characterized as "unreliable marrow juice" by Dameshek et al. in 1937 [18].

Lack of prognostic value of the thymidine-labelling index in adult acute leukaemia

A study has been made of the thymidine labelling index (TLI) of marrow blast cells in 201 adults with untreated acute leukaemia. There was no significant difference between the TLI in 172 patients with acute myeloblastic leukaemia and 29 patients with acute lymphoblastic leukaemia. The TLI did not correlate with the age, sex, peripheral-blood or marrow blast-cell count, or the platelet count at presentation. In neither acute myeloblastic leukaemia nor acute lymphoblastic leukaemia was there any correlation between the TLI and the response to the initial therapy, the duration of the first complete remission or survival.

A simple rapid autoradiography for 3H-thymidine labeling index and its application to therapy of adult acute leukemia

Our simple rapid autoradiography for 3H-thymidine (3H-TdR) labeling index (LI) of leukemic cells was introduced. Thirty-nine adult patients with acute nonlymphocytic leukemia were treated under a new protocol using 3H-TdR LI as a parameter and inserting a trial of partial synchronization by Ara-C. The success rate of synchronization by Ara-C (rise of the LI up to 10%) was 62.5% out of 32 courses. By our regimen the complete remission (CR) rate of 71.4% in 35 first treated cases, that of 44.0% in 25 courses of recurrent cases, and a median survival of 12 months were achieved. A survey of literature revealed that our results were favorably compared with others. Our new protocol is advantageous in permitting one to precisely know the proper time for chemotherapy and thus avoiding unnecessary side effects.

Proliferation kinetics and cyclic AMP as prognostic factors in adult acute leukemia

In 41 adult patients with acute leukemia (myeloblastic, lymphoblastic, and undifferentiated), proliferation kinetics (as determined by double-label autoradiography) and cyclic adenosine 3',5'-monophosphate (cAMP) concentration were studied for their significance in the prediction of responsiveness to cytostatic therapy. Patients with good clinical response had significantly shorter turnover times and higher labeling indices in the bone marrow than did those who failed to respond to treatment. Cases for which cell kinetics did not correlate with clinical response were explained by variance in the distribution of leukemic blasts between the proliferative cell cycle and the resting pool. Good clinical response was also found to be associated with low levels of cAMP in leukemic cells prior to therapy, whereas high cAMP contents predicted failure. Low cAMP concentrations, however, did not necessarily correlate with short turnover times and vice versa. This might be due to fluctuations of the cAMP concentrations during the cell cycle.