S phase determination in intact colonic crypts by histone H3 messenger RNA in situ hybridization and confocal microscopy.

Proliferating cells have a restricted three-dimensional spatial distribution within the crypt, which is the proliferative unit of the colon. Accurate quantitative and spatial analyses of S phase cells in the colon have therefore been limited by histological techniques. To overcome these limitations, S phase cells in microdissected intact colonic crypts of control, modified-starved, and refed rats were labeled by histone H3 in situ hybridization and analyzed by confocal microscopy. High-resolution digital images of the crypt cell nuclei stained with cyanine nucleic acid and of the labeled S phase cells were produced from confocal microscopic optical crypt sections. The S phase labeling index (LI) per whole crypt significantly (P < 0.001) discriminated the proliferative differences between control, modified-starved, and refed rats and correlated (r = 0.92) with the LI determined from histological crypt sections of the same rats. The variance component of the LI attributable to differences between whole crypts, 0.44 (95% confidence interval, 0.38-0.51), was considerably smaller than that attributable to differences between histological crypt sections, 6.07 (95% confidence interval, 5.18-6.96). Confocal microscopy and histone H3 in situ hybridization of intact three-dimensional crypts enables precise in vitro quantitation and spatial analysis of the total and S phase crypt cells.

Cell kinetic analysis of intact rat colonic crypts by confocal microscopy and immunofluorescence.

BACKGROUND & AIMS: Precise quantitative and spatial analysis of cell cycle-related biomarkers in colonic crypts is often vital for studies of colon carcinogenesis and cancer prevention. To overcome the limitations of histology, confocal laser microscopy of microdissected whole crypts was used to quantitate S phase and mitotic cells. METHODS: Microdissected distal colonic crypts were studied in a modified rat starvation refeeding model. S phase cells were labeled in vivo with 5-bromodeoxyuridine. Mitotic cells were labeled with MPM2 (antibody to mitosis-specific epitope) and also assessed for chromatin morphology with propidium iodide. Sequential optical crypt sections, produced by confocal microscopy, were digitally imaged. S phase labeling indices per whole crypt were also compared with those derived by conventional immunohistochemistry. RESULTS: S phase and mitotic cells were clearly discriminated without background staining. The labeled S phase cell number and fraction per whole crypt were significantly decreased with starvation and increased with refeeding. Variability in the labeling index between whole crypts analyzed by confocal microscopy was significantly smaller than between histological crypt sections. Consequently, the intervention contributed to 92.2% of the total variability of the labeling index in whole crypts but only to 59% of the variability in histological sections. CONCLUSIONS: Major limitations of histology are overcome by crypt microdissection and confocal microscopic analysis. The total crypt cell population as well as labeled M phase and S phase cells can be imaged, localized, and quantitated with improved precision.

Transformation of chronic lymphocytic leukemia to lymphoma of true histiocytic type.

BACKGROUND: Chronic lymphocytic leukemia (CLL) may evolve into large cell lymphoma (Richter's syndrome), prolymphocytic leukemia, acute lymphoblastic leukemia, and myeloma. METHODS: A patient with CLL that transformed into a lymphoma of true histiocytic type is described, and the literature on the association of these two disorders is reviewed. RESULTS: Lymphomas of true histiocytic type developing as an aggressive terminal phase of CLL previously have been reported in nine patients. Fever and rapidly increasing lymphadenopathy and splenomegaly were the most common signs and symptoms. As with de novo lymphoma of true histiocytic type, extranodal involvement of the soft tissue, gastrointestinal tract, kidneys, bone marrow, liver, and lungs was documented among the 10 patients with lymphoma of true histiocytic type transformed from CLL. The median interval between diagnosis of CLL and the evolution to lymphoma of true histiocytic type was 25.5 months. Patients with lymphomas of true histiocytic type after CLL were treated with fludarabine and various other combination chemotherapy regimens with only short-lived responses. The median time to death after transformation was only 33 days (range, 10 days to 5 months). CONCLUSION: Lymphomas of true histiocytic type appear to represent an additional, though uncommon, form of transformation in CLL. Although their presentation is reminiscent of other intermediate to high grade lymphomas, they can be distinguished based on their morphologic and immunophenotypic features. In the patients described in this study to date, transformation of CLL to lymphomas of true histiocytic type is a poor prognostic sign, with survival generally of only days to weeks.

Cell cycle-related shifts in subcellular localization of BCR: association with mitotic chromosomes and with heterochromatin.

The disruption of the BCR gene and its juxtaposition to and consequent activation of the ABL gene has been implicated as the critical molecular defect in Philadelphia chromosome-positive leukemias. The normal BCR protein is a multifunctional molecule with domains that suggest its participation in phosphokinase and GTP-binding pathways. Taken together with its localization to the cytoplasm of uncycled cells, it is therefore presumed to be involved in cytoplasmic signaling. By performing a double aphidicolin block for cell cycle synchronization, we currently demonstrate that the subcellular localization of BCR shifts from being largely cytoplasmic in interphase cells to being predominantly perichromosomal in mitosis. Furthermore, with the use of immunogold labeling and electron microscopy, association of BCR with DNA, in particular heterochromatin, can be demonstrated even in quiescent cells. Results were similar in cell lines of lymphoid or myeloid origin. These observations suggest a role for BCR in the phosphokinase interactions linked to condensed chromatin, a network previously implicated in cell cycle regulation.

Long-term prognostic importance of primary Ki-1 (CD30) antigen expression and anaplastic morphology in adult patients with diffuse large-cell lymphoma.

BACKGROUND: We retrospectively assessed the long-term prognostic importance of primary CD30 antigen expression and of anaplastic large-cell morphology (ALCL) in adult patients with previously untreated diffuse large-cell lymphoma (DLCL), including cases of immunoblastic lymphoma, and identified their clinical features. MATERIALS AND METHODS: We examined available archival paraffin-embedded or frozen pathologic material and medical records of adult patients with previously untreated DLCL seen at M.D. Anderson Cancer Center (MDACC) between January 1978 and May 1989. RESULTS: Sixty-seven cases of DLCL and seven cases of IBL (a total of seventy-four heretofore referred to as DLCL) were identified. Twenty-two of the 74 patients were positive for the CD 30 antigen. For these 22 patients the rates of complete remission, survival, and time to treatment failure (TTF) were 86%, 82%, and 77%, respectively, at 81 months. When compared with the group of 54 patients which stained negative for CD 30, the long term survival of CD 30-positive DLCL was favorable (82% vs. 49%, p = 0.08). ALCL morphology was present in two-thirds of the patients with CD 30-positive DLCL but did not affect survival and TTF rates. Among patients with CD 30-positive DLCL, 16 patients without skin involvement were younger and had a low failure rate (13%) compared with six patients with skin involvement who were older and had a high failure rate (50%); however, the latter group had a more indolent course after failure and thus both groups had similar survival rates. CONCLUSIONS: Primary CD 30 positivity is associated with a favorable long-term prognosis in adult patients with DLCL treated with doxorubicin-containing chemotherapy. ALCL morphology among these patients does not affect the outcome. Patients with CD30-positive DLCL and skin involvement have a higher failure rate than those without skin involvement, but similar overall survival.

Fluorescent in situ hybridization and cytogenetic studies of trisomy 12 in chronic lymphocytic leukemia.

Cytogenetic studies (CG) of 475 chronic lymphocytic leukemia (CLL) cases showed trisomy 12 in 6.1% or 26% of patients with abnormal karyotypes. Fluorescence in situ hybridization (FISH) detected trisomy 12 in 35% of 117 CLL patients. Only 34.6% of cases detected by FISH were detected by CG. Twelve patients had low levels of trisomic cells (4% to 11%) relative to clonal B cells (47.5% to 86%), suggestive of clonal evolution. Untreated patients with trisomy 12 were predominantly male (P < .05) and had an increased incidence of splenomegaly (P < .03). Patients with trisomy 12 were more likely to be previously treated and had advanced Binet stage compared with those without trisomy 12. The median survival was shorter in patients with trisomy 12 (7.8 years) and patients with other chromosomal abnormalities without trisomy 12 by FISH (5.5 years) than in patients with diploid karyotypes (14.4 years). The response to fludarabine was similar to that of patients with diploid karyotypes, but there was a trend for earlier disease progression. FISH detected residual disease in all patients with trisomy 12 in complete (n = 6) or partial remission (n = 4). As few as 1 trisomic cell in 5,000 was detected by performing FISH on fluorescence-activated cell sorter-sorted cells. Trisomy 12 was absent in T cells in patients with trisomy 12. We conclude that FISH identifies trisomy 12 approximately 2.6 times more often than CG, readily identifies minimal residual disease, and predicts for a shorter median survival.