DNA and nuclear protein measurement in isolated nuclei of human endometrium

A robust flow-cytometric protocol for assessing growth rate of hatchery-reared barramundi Lates calcarifer larvae

In this study, a flow-cytometric cell cycle analysis method to assess instantaneous growth rate of whole larvae of the Australian barramundi Lates calcarifer was developed and validated. High-resolution DNA measurements of either fresh, frozen or RNAlater-preserved larvae (gap0-gap1, G(0) -G(1), coefficient of variation (c.v.) < 3, 4 and 5%, respectively) enabled the deconvolution of the DNA histogram and assignment of the proportion of nuclei into cell cycle compartments G(0) -G(1), S (DNA synthesis) and G(2) -M (Gap2-Mitosis). This technique can be also used for individual fish tissues such as brain, liver, fin and muscle. For the first time, the combined proportion of replicating nuclei (into S and G(2) -M phases) of whole fish larvae and absolute growth rate in length (mm day(-1)) has been correlated in commercial aquaculture conditions. Fast growing L. calcarifer larvae had an overall hyperplasia advantage as indicated by a greater proportion of cells in the S+G(2) -M phase compared with slow growing larvae, which might explain the increasing differences in size during culture. In a fasting trial, larvae ceased growth while maintaining the constant initial rates of cell division throughout a 6 day period. For a highly fed fast growing control group, cell division rates significantly increased after day 4. Flow-cytometric cell cycle analysis of whole fish larvae may provide fish biologists and aquaculturists with a better understanding of how cell division rates influence early growth in natural and artificial environments.

Nuclear protein as a prognostic factor of growth activity in prostatic adenocarcinoma

The value of nuclear protein (NP) as a prognostic parameter in prostatic adenocarcinoma was investigated. The NP and DNA contents of two prostatic tumour lines with a well-documented hormonal dependency (PC-82, PC-EW) were compared to the NP and DNA contents of two xenografts with only partial or no response to androgen deprivation (LNCaP, PC-133). After hormonal treatment the PC-82 and PC-EW tumours showed a significant decrease in the NP/DNA ratio, which coincided with a decrease in the proliferative activity [anti-bromodeoxyuridine (BRDU) antibody-labelling index] of the same specimens. In the fast-growing LNCaP tumour an increased percentage of cells with high NP and DNA contents was found. The tumours PC-82, PC-EW, and PC-133 with lower proliferative activity showed lower nuclear protein and DNA contents. In a pilot study of 20 prostatic biopsies the amount of nuclear protein and DNA in grade 1-3 tumours as well as in dysplasia was measured. Statistically significant differences (P < 0.002) were found between grade 1 and grade 3 tumours. The mean NP/DNA ratio was increased in high-grade malignancies. Nuclear protein appeared to be a potential parameter in predicting growth activity in prostatic carcinoma.

Cellular heterogeneity of DNA/total-protein content in human lung tumors, as determined by flow cytometry

With the aim of distinguishing neoplastic cell sub-populations of different prognostic and diagnostic significance, dual-parameter measurements (DNA/protein) have been simultaneously determined in a (256, 256) channel matrix in lung samples derived from 110 patients affected by neoplastic and non-neoplastic lung diseases. Biparametric analysis demonstrated that cells with abnormally high red fluorescence (i.e., protein content), which is indicative of unbalanced growth, were often observed in malignant tumors as compared with normal lung samples. Furthermore, the dual-parameter analysis allowed recognition of additional aneuploid tumor-cell lines, indicating that the frequency of cytometrically determined diploid tumor is lower than that previously described by DNA monoparametric analysis. The recognition of aneuploid subpopulations by dual-parameter analysis in clinically and histologically negative one-parameter flow-cytometric "diploid" samples assumes important diagnostic value. The results have also shown the presence of multiple protein sub-populations in clones with the same ploidy value, indicating a higher level of cellular heterogeneity than demonstrated by DNA monoparametric measurements.

Cytometric DNA analysis in the management of cancer. Clinical and laboratory considerations

Clinically, cytometric DNA (ploidy and proliferative fraction) analysis is primarily used in the determination of tumor prognosis. This determination has a clinical impact primarily in low stage tumors where therapeutic options are available, rather than in higher stage tumors that will be treated the same independent of their ploidy or proliferative fraction. In general, the best available data indicate that for most tumors aneuploidy is an indicator of more aggressiveness. Ploidy analysis is independent of other prognostic indicators in many tumors and is the most significant prognostic indicator in some. More recent data suggest that proliferative fraction, the percentage of tumor cells in the S-phase of the cell cycle, may be as important an indicator of tumor prognosis as simple presence of aneuploidy. However, the poor interlaboratory reproducibility of S-phase measurements as currently performed limits the general applicability of this measurement in the management of patients.

DNA ploidy, morphometry, and nuclear grade as prognostic factors in endometrial carcinoma

In a retrospective analysis of 106 cases of endometrial carcinoma stages I-IV (FIGO), the prognostic value of DNA ploidy and nuclear morphometry of tumor cells was evaluated and compared with that of conventional clinical and histopathologic parameters. Paraffin-embedded tumor tissue from the original curettage specimens was used. A flow cytometric technique was employed to distinguish diploid from aneuploid tumors. It was not possible to estimate S-phase rates by this method. Eight different nucleus-related morphometric parameters were computed from representative tumor regions on the original slides. All histologic specimens were reviewed by on the pathologist and graded according to FIGO; nuclear grade was determined separately. Tumor stage, depth of myometrial infiltration, and nuclear grade were the most important prognostic factors with regard to tumor-related survival. DNA ploidy and nuclear morphometry did not add significant prognostic information that could be used to distinguish high-risk and low-risk populations with endometrial carcinomas. The simple nuclear grading system should be further evaluated in prospective studies and compared with DNA analysis and nuclear morphometry performed on fresh-frozen tissue.

The prognostic significance of growth pattern and its relation to tumor cell nuclear DNA content in endometrial carcinoma

Hysterectomy specimens from 21 endometrial carcinoma patients, who died from their disease, and 23 patients selected at random from 307 survivors, were analysed for tumor growth pattern and tumor cell nuclear DNA content. The results indicate that tumor growth pattern, reflected by the mode of infiltration, is significantly correlated to the clinical course of the disease. Patients with carcinomas exhibiting contiguous growth pattern had a better outcome than patients with discontiguously growing carcinomas. It was also found that tumor growth pattern correlated well with tumor nuclear DNA content. It is suggested that the pattern of infiltration of the tumors is a sensitive predictor of prognosis and that this prognostic information, which only can be obtained postoperatively, to a large extent is reflected by tumor cell nuclear DNA content in curetted diagnostic material, obtained prior to treatment.

A double staining method for measuring DNA content of specific cell populations utilizing computerized microscopy

A method for identifying specific cell populations with the computerized microscope is described. This method utilizes double staining techniques using immunofluorescent antibodies and the Feulgen technique. It was applied to measure the area and DNA content of the nuclei of beta-cells in patients with Persistent Neonatal Hypoglycemia with Hyperinsulinism (PNHH). A significant increase in the area and DNA content was found in nuclei of patients compared to a control group. This method may be applied to sample cells from other tissues as well.

Evaluation of DNA and nuclear protein features for their use in describing normal and malignant endometrium

Different feature sets (geometric, densitometric, and textural) derived from DNA and nuclear protein staining were evaluated for their use in describing atrophic, secretory, and proliferative endometrium, and well-differentiated stage I and moderately differentiated stage I adenocarcinomas of the endometrium. It was found that the pattern of significant differences among these groups varied between feature sets, while remaining consistent within a set of features. The DNA density and run-length features were not very effective in describing group mean differences, whereas the co-occurrence features revealed significant differences among most groups. The protein run-length features were the only ones that consistently showed a difference between proliferative endometrium and well-differentiated adenocarcinomas. Analyses repeated on only cells in the G0/G1 DNA region improved the differentiation between moderately differentiated adenocarcinomas and the other groups. It was concluded that the use of DNA and nuclear protein texture features are effective in describing group differences that cannot be described by DNA content only.

DNA and nuclear protein measurement in columnar epithelial cells of human endometrium

Propidium iodide DNA flow cytometry, Feulgen-DNA, and nuclear light green protein scanning cytometry were performed in columnar epithelial cells of normal, nonmalignant human endometrium and endometrial adenocarcinomas. Columnar cells were identified by immunohistochemical staining for cytokeratin 18, an intermediate filament protein specifically present in columnar cell epithelium. DNA measurements derived from flow and scanning cytometry showed comparable results. The DNA content of the G0/G1 fraction of the adenocarcinomas had a considerable overlap with that of normal endometrium, with that of the carcinomas shifted toward higher values. For the carcinomas, no correlation was found with the histological grade, with the exception of the adenosquamous carcinomas. Most of the clinical stage I tumors showed a DNA content in the normal diploid region. Three of the four carcinomas of clinical stage II and higher had an increased DNA content. For the carcinomas, the percentage of cells in the proliferative fraction, as determined from scanning cytometric derived DNA histograms, was comparable to that of normal endometrium, or higher. No correlation was found with the histological grade. Tumors of clinical stage II and higher had intermediate values compared to carcinomas of lower stages. The nuclear protein/DNA ratio of malignant endometrium completely overlapped that of normal endometrium. Within the tumor population, no correlation was found with the histological grade, with the exception of the adenosquamous carcinomas, and clinical stage. Based on the aforementioned parameters, no discrimination could be obtained between normal and malignant endometrium. However, when the DNA content of the G0/G1 fraction was combined with the coefficient of variation of the nuclear protein/DNA ratio, a clear discrimination could be obtained with only two false-positive cases.