Signal antonymy unique to myelodysplastic marrows correlates with altered expression of E2F1

Myelodysplastic syndromes (MDS) have previously been reported to show competitively high rates of apoptosis and proliferation in the bone marrow (BM). Using a double-labelling technique in the present study, we demonstrated that a significantly high number of S-phase cells were simultaneously apoptotic (signal antonymy; SA) in MDS (mean +/- s.e.m. 53.5 +/- 6.7%, n = 24, P < 0.001). In contrast, SA was negligible in all other specimens studied, including normal control BM (n = 13) from non-Hodgkin's lymphoma (NHL) patients, BM from patients with de novo acute myelogenous leukaemia (1'AML; n = 5), or secondary AML that had transformed from MDS (2'AML; n = 10), or the solid tumours from patients with NHL (n = 9) or head and neck squamous cell carcinoma (HNSCC; n = 10). Subsequently, the expression of a transcription factor, E2F1, was studied in density-separated BM aspirate mononuclear cells from MDS patients (n = 9) and a normal control. Two separate sets of primers were used that recognized the regulatory retinoblastoma (Rb) protein-binding region and the functional DNA-binding region of E2F1. Interestingly, although the latter manifested the expected band (280 bp) in all samples, the Rb-specific primers showed the expected band (380 bp) in the normal and in 4/9 MDS specimens. Two other MDS specimens also showed a smaller band ( approximately 325 bp), whereas 3/9 MDS patients showed exclusively the smaller band. The levels of SA were significantly higher in those MDS cases that showed the smaller Rb-specific band either alone or in addition to the expected band (median 19.5%, n = 4, P = 0.037) than in those showing exclusively the expected band (median 0.4%, n = 3). Our present studies show SA as a characteristic feature of MDS and, importantly, demonstrate its link with an altered expression of E2F1 in some MDS patients.

The clinical and biologic significance of abnormal lipid profiles in patients with myelodysplastic syndromes

Serum lipid profiles were obtained in 108 patients with myelodysplastic syndrome (MDS) and compared to 28 healthy volunteers. Serum cholesterol and low-density and high-density lipoproteins (LDL and HDL) were found to be significantly lower in MDS patients than in normals (p = 0.0001, 0.0038 and 0.037, respectively). This difference was significant for all MDS categories. Serum cholesterol and HDL were negatively related to biopsy cellularity (p = 0.001 and 0.0001, respectively), and serum triglycerides were negatively related to labeling index (p = 0.0003). No differences were noted in the lipid profiles of MDS patients with normal versus abnormal karyotypes. However, low-risk MDS patients with abnormal karyotypes had significantly lower triglyceride levels compared with the high-risk patients (p = 0.027), as did low-risk patients with normal cytogenetics (p = 0.015). Serum HDL levels were significantly higher for the low-risk group with normal cytogenetics as well (p = 0.003). We conclude that serum cholesterol, LDL, and HDL are significantly reduced in MDS patients, probably indicating excessive intracellular lipid biosynthesis in the expanding clone. These relatively simple measurements could serve as important prognostic markers and reliable indicators of disease activity in individual patients. Prospective studies to determine their utility as independent variables that guide the need for active therapeutic intervention are warranted.

Patients with myelodysplastic syndromes benefit from palliative therapy with amifostine, pentoxifylline, and ciprofloxacin with or without dexamethasone

Thirty-five patients with myelodysplastic syndrome (MDS) were registered on protocol MDS 96-02 and were receiving continuous therapy with pentoxifylline 800 mg 3 times a day and ciprofloxacin 500 mg twice a day by mouth; dexamethasone was added to the regimen for the partial responders and the nonresponders after 12 weeks at a dose of 4 mg by mouth every morning for 4 weeks. Amifostine was administered intravenously 3 times a week at 3 dose levels (200 mg/M(2), 300 mg/M(2), and 400 mg/M(2)) to cohorts of 10 patients each. Therapy has been continued for 1 year in responders. Twenty-nine have completed at least 12 weeks of therapy and are available for response evaluation. Of the 21 men and 8 women (median age, 67 years), 20 had refractory anemia (RA), 3 had RA with ringed sideroblasts (RARS), 5 had RA with excess blasts (RAEB), and 1 had chronic myelomonocytic leukemia (CMMoL). Five had secondary MDS. No differences were noted in response rates among the 3 dose levels. Seven patients did not respond at all, and 22 showed an improvement in cytopenias (76%). Three had a triple lineage response, 10 had a double lineage response, and 9 had a single lineage response (8 of 9 in absolute neutrophil count [ANC] and 1 had more than a 50% reduction in packed red blood cell transfusions). Fifteen patients responded only after the addition of dexamethasone, whereas 7 responded before. When examined by lineage, 19 of 22 showed improved ANC, 11 of 22 demonstrated more than 50% reduction in blood transfusions, improved Hb levels, or both, and 7 of 22 showed improvement in platelet counts. Interestingly, the responses were frequently slow to appear, and continued improvement in counts was seen up to 12 months of therapy and beyond. This study supports the feasibility of treating patients with MDS with the unique approach of cytoprotection and anticytokine therapies as well as the principle that prolonged commitment to treatment is desirable when noncytotoxic agents are administered. (Blood. 2000;95:1580-1587)

Telomerase activity in preleukemia and acute myelogenous leukemia

The development of acute leukemia from preleukemia involves the appearance of clones with increasing proliferative potential. The studies described here demonstrate that telomerase activity progressively increases as the bone marrow cells acquire increasing proliferative potential. This was demonstrated by measuring telomerase activity in normal bone marrow, in post-treatment lymphoma marrows with skewed Lyonization, and in MDS and AML marrows. The greater telomerase activity in myelodysplastic marrow than in normal marrow is not due to a higher proportion of blast cells or to a higher proliferative rate of the MDS marrow. These data demonstrate that the increasing proliferative potential of the marrow which occurs during the development of AML is associated with a simultaneous increase in telomerase activity.

Consilience across evolving dysplasias affecting myeloid, cervical, esophageal, gastric and liver cells: common themes and emerging patterns

In the present paper, an attempt is made to identify common biologic themes across dysplastic states affecting the marrow, gastro intestinal tissue, the cervix and liver as well as unifying patterns during disease evolution. The following algorithm appears generally applicable, although individual variations must necessarily be anticipated. It appears that there is an initial transforming event which in all dysplasias except that affecting the marrow has been found to be infectious. Increased cellular proliferation-increased apoptosis, telomere shortening, appearance of telomerase expression and clonal expansion follow the initial insult. Abnormalities in the cytokine environment are universally described and it is likely that the quintessential monoclonality aspect of dysplasia predisposes to accumulation of genetic mutations, and microsatellite instability leading to the appearance of evolved sub-clones. The conversion of a dysplastic phenotype to a malignant one reflects the success of one such sub-clone in developing a survival advantage over a large population of prematurely apoptotic neighbors. This state is usually acquired by silencing tumor suppressor genes through hypermethylation or actual loss or dysfunction. Thus, excessive apoptosis of cells resulting from a persistent infectious process predisposes the organ towards developing a cancerous phenotype. Evidence for the shared pathology is presented at length with the hope that these parallels between dysplastic states will be helpful in both biologic and therapeutic research.

Measurement of mRNA expression for a variety of cytokines and its receptors in bone marrows of patients with myelodysplastic syndromes

BACKGROUND

Myelodysplastic syndromes (MDS) are a group of disorders characterized by ineffective and dysplastic haemopoiesis. Previous studies in the lab have shown extensive apoptosis and high levels of transforming growth factor (TGF-beta) and tumor necrosis factor (TNF-alpha) in the stromal layer of MDS bone marrow. The current study focuses on the cytokines expressed in the bone marrow parenchymal cells.

MATERIALS AND METHODS

Bone marrow aspirate from 5 normal donors and 26 patients with myelodysplastic syndromes were examined for mRNA expression of tumor necrosis factor alpha (TNF-alpha), macrophage colony stimulating factor (M-CSF), Flt-3 Ligand (Flt-3L), Flt-3 receptor(Flt-3 rec), interleukin 1 beta (IL 1 beta) and interleukin 1 receptor antagonist (IL-1 ra).

RESULTS

Comparison of 26 MDS marrows with 5 normals showed a significantly higher value for Flt-3 rec and IL 1 beta (p = 0.031 and p = 0.031) in the former, while only Flt-1 beta rec was considerably higher (p = 0.016) in newly diagnosed patients. In previously diagnosed group, Flt-3 rec (p = 0.001), TNF-alpha (p = 0.04) and IL-1 beta (p = 0.016) were higher than normal while there was no statistically significant difference in the newly versus previously diagnosed MDS cases:

CONCLUSION

mRNA expression of all six cytokines measured were considerably higher in MDS when compared to normal and that these levels tend to increase with disease duration. The precise source of these cytokines as well as their role in MDS pathogenesis remains to be determined, but this study confirms our previous reports that there is no dearth of cytokines in these bizarre myelosuppressive states.

Fine needle aspiration (FNA) biopsy of palpable breast masses: comparison of conventional smears with the Cyto-Tek MonoPrep system

BACKGROUND

One of the limitations preventing the widespread use of fine-needle aspiration (FNA) is that it requires skill to obtain an adequate sample and well prepared smears. In this study, a new monolayer technique, the Cyto-Tek MonoPrep (MP) system, which obviates the need for smear preparation, was evaluated against conventional smear (CS) preparation for palpable breast lesions.

METHODS

A total of 44 paired CS/MP breast FNA specimens were studied. The authors blindly analyzed the CS and the MP slides separately, then by a side-by-side evaluation. The two methods were compared with respect to diagnostic concordance, cellularity, cell preservation, background debris, and time needed to prepare and diagnose each case.

RESULTS

An exact diagnostic correlation was present in 34 of 44 (77%) cases. The 10 noncorrelating cases were caused by decreased cellularity in the MP cases; nonetheless, 7 of these were correctly assigned to the right general diagnostic category, whereas the remaining 3 cases had insufficient cells. In addition to overall lesser cellularity on MP, fibroadenoma cases had smaller epithelial sheets and absence of stroma compared with CS. Both methods had comparable cellular preservation and diagnostic evaluation time, but background debris and preparation time were greater for MP.

CONCLUSION

CS are favored over MP for the preparation of breast FNA specimens in centers with specialized FNA services because of their higher diagnostic yield, ease of preparation, and availability for immediate cytologic evaluation. However, in settings where specimens are collected sporadically by unskilled clinicians, the MP system may prove to be useful as an alternative or an adjunct to CS. Cancer (Cancer Cytopathol)

Marrow cytokine transcripts and the secondary hematologic disorders

A comparison was made of the cytokine transcripts in normal, monoclonal, MDS, and AML marrow aspirates. While both normal and monoclonal marrow aspirates contain transcripts for SCF, few MDS or AML marrow aspirates contain these transcripts. Similarly, IL1ra transcripts are found with reduced frequency in MDS and AML marrow aspirates. The fall in SCF transcripts between monoclonal and MDS marrow aspirates parallels the appearance of apoptosis and the reduced in vitro proliferative ability which are characteristics of MDS marrow aspirate cells. The frequent IL1beta production by MDS and AML marrow aspirate cells, with few marrow aspirates producing IL1ra transcripts, suggests that unbalanced IL1beta effects may contribute to the proliferative advantage of MDS and AML cells over their normal counterparts.

Spontaneous down-regulation of Fas-associated phosphatase-1 may contribute to excessive apoptosis in myelodysplastic marrows

In this study, we examined the role of Fas-signaling in the apoptotic pathway in myelodysplastic syndromes (MDS). Ficoll-separated mononuclear cells from 18 bone marrow aspirate specimens obtained from 17 MDS patients, 4 normal healthy donors, and 3 acute myeloid leukemia patients transformed from MDS (t-AML) were studied for mRNA expression of Fas-L, Fas, and the effectors of their signaling, Caspase 1 and Caspase 3, using reverse transcriptase polymerase chain reaction. Fas-L, Fas, and Caspase 1 were detectable in all of the samples in the three groups. Caspase 3 was detectable both in MDS and t-AML specimens but was negligible in normal cells. The apoptotic index (AI%) determined by in situ end labeling of fragmented DNA in 4-hour cultures of mononuclear cells was significantly higher in MDS cells compared to normal or t-AML cells (mean +/- SEM: 2.3% +/- 0.4% in MDS, n = 10 vs. 0.6% +/- 0.2%, n = 4, P = 0.014 in normal cells, and 0.2% +/- 0.2%, n = 3, P = 0.007 in t-AML cells). Treatment of MDS cells with anti-Fas-L antibody suppressed apoptosis (AI%: 2.1% +/- 0.6% in untreated vs. 1.37% +/- 0.5% in treated, n = 6, P = 0.02), indicating functional participation of Fas-signaling in MDS. Further, it was found that Fas-L, Fas, and Caspase 1 mRNA expression remained unchanged in 4 hours. Caspase 3 expression appeared in normal cells after 4 hours and was present at both 0 and 4 hours in MDS and t-AML cells. In contrast to persistent expression in normal and t-AML cells, cells from the 5 MDS patients studied consistently showed significantly lowered or undetectable expression of a negative regulator of Fas, called Fas-associated phosphatase-1 (Fap-1) after 4 hours. Thus, the high AI% in MDS corresponds to a rapid decline in Fap-1. Furthermore, in tumor necrosis factor alpha (TNF-alpha) treated HL60 promyelocytic cells, a definite periodicity in the expression of different mRNAs was observed with upregulation of TNF-alpha itself at 30 minutes, increased expression of Fas and the appearance of Fas-L after 2 hours, and a decrease in Fap-1 expression after 8 hours. These results suggest that TNF-alpha not only induces the effectors of Fas-signaling but also may downregulate the inhibitor. We conclude that a spontaneous and rapid down-regulation of Fap-1, possibly induced by TNF-alpha, a cytokine shown to be present in excess in MDS marrows, may underlie the increased apoptotic death of hematopoietic cells in these patients. Interference with Fap-1 turnover may provide a new therapeutic modality for MDS.

Sequential activation of caspase-1 and caspase-3-like proteases during apoptosis in myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are a group of hematopoietic disorders characterized by the concomitant presence of peripheral cytopenias and normocellular to hypercellular BM. This paradox has been proposed to be due to the presence of excessive proliferation matched by excessive intramedullary apoptosis of hematopoietic cells. When cultured in vitro MDS BM mononuclear cells (BMMC) undergo apoptosis within 4 h. We measured caspase-1-like and caspase-3-like activity in 22 MDS and 4 normal BM immediately following cell separation or after 4 h culture. When cultured in vitro, MDS BMMC demonstrated an increased apoptotic index within 4 h as measured by in situ end-labeling of fragmented DNA that was matched by a concurrent increase in caspase-3-like specific activity, and the two were significantly correlated. During the 4 h culture, a sequential activation of caspase-1-like and caspase-3-like activities was detected. Caspase-1-like specific activity was detected early and transiently at approximately 15 min, followed by a gradual increase in caspase-3-like-specific activity peaking at 2 h. When the broad-spectrum caspase inhibitor, Z-VAD.FMK, was included in the MDS BM aspirate 4 h culture, apoptosis was attenuated. We conclude that sequential activation of caspase-1-like and caspase-3-like activities may form the central biochemical pathway of apoptosis in BMMC from some MDS patients, and prevention of this process by caspase inhibitors may be of significant therapeutic value for these patients, in whom supportive care continues to be the mainstay of therapy.

Correlation of tumor necrosis factor alpha (TNF alpha) with high Caspase 3-like activity in myelodysplastic syndromes

Increased intramedullary apoptotic death of hematopoietic cells is thought to contribute to the ineffective hematopoiesis in myelodysplastic syndromes (MDS). Furthermore, high amounts of tumor necrosis factor alpha (TNF alpha) have previously been correlated with apoptosis in MDS marrows. The present studies were undertaken to examine the status of two key downstream effectors of TNF alpha signaling, i.e. Caspase 1 and Caspase 3 enzymes, using a fluorometric assay in the bone marrow aspirate mononuclear cells (BMMNC) in relation to apoptotic DNA fragmentation detected by in situ end-labeling (ISEL) of DNA and with localization of TNF alpha in the corresponding biopsies from 14 MDS patients. Both Caspase 1 and 3 were detectable in freshly harvested BMMNC, albeit median Caspase 3 levels (47.5 units/mg protein) being almost 10 times higher than Caspase 1 (4.0 units/mg protein). Upon short-term culture for 4 h in a serum-supplemented medium in vitro a significant increase was seen in Caspase 3 activity (58.8 +/- 13.9 at 0 h vs. 177.8 +/- 55.2 units/mg protein at 4 h, n = 14, P = 0.017) and in percent cells labeled by ISEL (apoptotic index or AI%: 0.76% +/- 0.25% vs. 3.99% +/- 1.1%, n = 14, P = 0.004, respectively). Caspase 1 activity increased after 15 min in culture. Interestingly, TNF alpha levels measured by immunohistochemistry correlated with the net increase in Caspase 3 activity after 4 h (p = 0.517, n = 13, P = 0.07) and the starting levels of Caspase 1 at 0 h correlated with the Caspase 3 levels attained at 4 h (p = 0.593, n = 13, P = 0.033). Additionally when TNF alpha-positive bone marrows (8/14) were compared with the negative marrows (6/14) the Caspase 3 levels were significantly higher in the TNF alpha-positive marrows (189.6 +/- 66.2 vs. 25.0 +/- 14.6 units/mg protein, respectively, P = 0.043). The increase in AI%, though not statistically significant, was also higher in the TNF alpha-positive marrows. Finally in HL60 cells the effects of different Caspase inhibitors and pentoxifylline (PTX) (interferes with lipid signaling of cytokines) on TNF alpha-induced apoptosis were evaluated. TNF alpha treatment significantly increased AI% (P < 0.003) as compared to the untreated controls. A co-treatment with three Caspase inhibitors, zVAD.FMK (inhibitor of Caspases 1 and 3, 10 microM/l), Ac.YVAD.FMK (Caspase 1 inhibitor, 1 microM/l), Ac.DEVD.FMK (Caspase 3 inhibitor, 10 microM/l) as well as PTX (250 microM/l) significantly curtailed the AI% induced by TNF alpha. The present studies thus identify the downstream effectors of TNF alpha-inducible apoptosis in MDS and so also the suppressors of TNF alpha apoptotic signaling. These results may have significant clinical implications in the therapy of MDS in the future.

The effects of EMLA and a topical formulation of 4% amethocaine (Ametop) on pain associated with retrobulbar injection

Retrobulbar block is commonly performed to provide anaesthesia for cataract extraction. This technique can cause significant discomfort. A prospective, randomised, placebo-controlled trial was carried out to investigate the efficacy of a eutectic mixture of local anaesthetics (EMLA) and a 4% amethocaine topical formulation (Ametop) in reducing the pain of retrobulbar injection. Ametop and EMLA proved to be of similar efficacy, both being superior to a placebo in alleviating the discomfort of retrobulbar block. No significant side-effects were observed with the use of either formulation.

The relative extent and propensity of CD34+ vs. CD34- cells to undergo apoptosis in myelodysplastic marrows

The paradox of peripheral cytopenias despite cellular bone marrow (BM) observed in myelodysplastic syndromes (MDS) has been associated with excessive intramedullary apoptosis of hematopoietic cells. Since MDS is regarded as a stem cell disorder, the present studies were undertaken to examine the relative susceptibility and propensity of early progenitor CD34+ cells to undergo apoptosis as compared to more maturing/matured CD34- cells. Five serial studies were performed on 4 independent groups of 36 newly diagnosed MDS patients. First, in 2 separate groups of 16 and 8 patients each, measurement of the extent of apoptosis in CD34+ and CD34- fractions of the BM aspirate mononuclear cells was carried out using independent biparametric flow cytometry methods, CD34 labeling/terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) (n = 16), and CD34 labeling/reduced uptake of nucleic acid staining dye LDS751 (n = 8). The difference in the median degrees of apoptosis in CD34+ vs. CD34- cells was not statistically significant by either technique (P = 0.583 and P = 0.674 for TUNEL and LDS751, respectively). In the next group of 4 MDS patients, a double-labeling was performed on plastic embedded marrow biopsy sections, to detect CD34 antigen with specific monoclonal antibody and apoptosis by in situ end labeling (ISEL) of fragmented DNA. Despite high overall apoptosis (56.2% +/- 18.4%), only an occasional CD34+ cell was found to be simultaneously labeled with ISEL. Finally, in the last group of 8 MDS patients, CD34+ cells were separated from CD34- cells on affinity column and cultured in serum containing medium for 4 hours. At 0- and 4-hour time points, ISEL was carried out to label apoptotic cells. In addition, a fluorometric assay was employed to estimate the activity of a proapoptotic enzyme, Caspase 3. Both the net increase in % ISEL labeled cells (apoptotic index or AI) and Caspase-3 activity were significantly lower in CD34+ cells as compared to CD34- cells (AI, 0.87% +/- 0.5% vs. 3.97% +/- 1.4%, n = 6, P = 0.028 and Caspase-3 Units/mg protein, 46.9 +/- 25.0 vs. 71.7 +/- 23.03, n = 5, P = 0.042, respectively). We conclude that when estimated in a total population of mononuclear cells, CD34+ cells and CD34- cells show comparable degrees of apoptosis. However, once separated the CD34+ fraction demonstrates lower propensity to undergo apoptosis, thereby suggesting the CD34- fraction as being a possible source for proapoptotic signaling.

Biologic characteristics of patients with hypocellular myelodysplastic syndromes

Rates of proliferation and apoptosis as well as expression of tumor necrosis factor alpha (TNF-alpha), transforming growth factor beta (TGF-beta) and the number of macrophages were measured in bone marrow (BM) biopsies of 33 patients who presented with hypocellular (cellularity < 30%) myelodysplastic syndromes (MDS). Results showed that 2/3 of the patients had high apoptosis, high cytokine levels and large number of macrophages in their biopsies while 1/3 did not. Apoptosis and TNF-alpha levels were directly related (r = 0.583, P = 0.003, n = 24) as was apoptosis and the degree of anemia (P = 0.033, n = 18). A subgroup of patients with abnormalities of chromosomes 5 or 7 had higher platelets (P = 0.026) and higher apoptosis (P = 0.038) when compared with the rest of the group. Eight patients had no evidence of apoptosis and almost no detectable TNF-alpha in their biopsies. We conclude that within the hypocellular variant of MDS, there may be two distinct sub-groups of patients, one who present with high cytokine-mediated intramedullary apoptosis and the other who may be better characterized as having a stem-cell failure defect since they showed no evidence of apoptosis.

Biologic characteristics of 164 patients with myelodysplastic syndromes

Rates of proliferation, apoptosis and cytokine expression were measured in bone marrow (BM) biopsies of 164 myelodysplastic syndrome (MDS) patients. There were 107 males and 57 females. Median age was 69 years and 101 had refractory anemia (RA), 17 RA with ringed sideroblasts (RARS), 38 with RA and excess blasts (RAEB) and 8 with RAEB in transformation (RAEB-t). Apoptosis measured by in-situ end labeling (ISEL) was directly related to the number of macrophages (p = 0.028, n = 83). Mean tumor necrosis factor alpha (TNF-alpha) and ISEL positivity were higher in RAEB + RAEB-t patients (p = 0.0554 and p = 0.06 respectively) while hemoglobin was higher for RA + RARS group (p = 0.0472). Patients with high apoptosis had lower white blood cell counts (p = 0.0009), lower percentage of blasts (p = 0.0009) and higher number of macrophages (p = 0.0086). We conclude that measurements of apoptosis, proliferation and cytokine expression provide important biological information which helps to distinguish RA + RARS patients from RAEB + RAEB-t patients, and may be of additive prognostic significance.

Biological characteristics of myelodysplastic syndrome patients who demonstrated high versus no intramedullary apoptosis

Spontaneous intramedullary apoptosis was measured in bone marrow (BM) biopsies of 175 patients with myelodysplastic syndromes (MDS) using in situ end-labeling (ISEL) of fragmented DNA. Two groups of high (n=71) versus low (n =43) levels of apoptosis were identified while 61 patients were ISEL-negative. Semiquantitative assessment of 3 cytokines, the number of macrophages and in vivo labeling indices (LI) were also determined from consecutive sections of the biopsy. Patients with high apoptosis levels tended to have a high LI (p=0.013), more macrophages in their BM biopsies (p=0.006) and higher tumor necrosis factor alpha (TNF-alpha) levels (not significant) compared to patients with no apoptosis. In addition, low risk MDS patients had significantly lower rates of apoptosis (p = 0.047) and lower levels of TNF-alpha (p = 0.055) compared to high-risk MDS patients. We conclude that the genesis of cytopenias in MDS is of multifactorial origin and that cytokine-associated apoptosis clearly identifies a distinct biological subgroup of patients who may benefit selectively by use of anti-cytokine therapies.

Extensive apoptosis of bone marrow cells as evaluated by the in situ end-labelling (ISEL) technique may be the basis for ineffective haematopoiesis in patients with myelodysplastic syndromes

Apoptosis is a gene-directed cellular self-destruction which begins with internucleosomal cleavage of DNA and ends eventually with fragmentation of the nucleus. We have shown that the technique of ISEL of fragmented DNA appears to be an accurate and reliable measurement of the early stages of apoptosis. The present study was undertaken in order to define the incidence of programmed cell death in bone marrow (BM) haematopoietic and stromal cells of myelodysplastic syndromes (MDS). The ISEL technique was employed in 21 BM biopsies of MDS patients. The analysis showed that in 11/21 patients, >70% cells (high score) were undergoing programmed cell death while 5 patients showed up to 1/3 of the biopsy containing apoptotic cells and 2 patients had only few occasional ISEL positive cells. Stromal cells including fat cells, endothelial cells and fibroblasts were frequently in apoptosis in large clusters. Our results indicate that extensive apoptosis of haematopoietic cells documented in BM biopsies of MDS patients may be the explanation for the ineffective haematopoiesis which is the hallmark of these disorders.

Gangrenous cystitis: a rare cause of colovesical fistula

A case of gangrenous cystitis presenting as a colovesical fistula in an elderly woman is described. The literature on this rare condition is reviewed.

Evidence for involvement of tumor necrosis factor-alpha in apoptotic death of bone marrow cells in myelodysplastic syndromes

We previously reported excessive apoptosis and high levels of tumor necrosis factor-alpha (TNF-alpha) in the bone marrows of patients with myelodysplastic syndromes (MDS), using histochemical techniques. The present studies provide further circumstantial evidence for the involvement of TNF-alpha in apoptotic death of the marrow cells in MDS. Using our newly developed in situ double-labeling technique that sequentially employs DNA polymerase (DNA Pol) followed by terminal deoxynucleotidyl transferase (TdT) to label cells undergoing apoptosis, we have characterized DNA fragmentation patterns during spontaneous apoptosis in MDS bone marrow and in HL60 cells treated with TNF-alpha or etoposide (VP16). Clear DNA laddering detected by gel electrophoresis in MDS samples confirmed the unique length of apoptotic DNA fragments (180-200 bp). Surprisingly, however, phenotypically heterogeneous population of MDS cells as well as the homogenous population of HL60 cells showed three distinct labeling patterns after double labeling--only DNA-Pol reaction, only TdT reaction, and a combined DNA Pol + TdT reaction, albeit in different cohorts of cells. Each labeling pattern was found at all morphological stages of apoptosis. MDS mononuclear cells, during spontaneous apoptosis in 4 hr cultures, showed highest increase in double-labeled cells (DNA Pol + TdT reaction). Interestingly, this was paralleled by TNF-alpha-induced apoptosis in HL60 cells. In contrast, VP16 treatment of HL60 cells led to increased apoptosis in cells showing only TdT reaction. The double-labeling technique was applied to normal bone marrow and peripheral blood mononuclear cells after treatment with known endonucleases that specifically cause 3' recessed (BamHI), 5' recessed (PstI), or blunt ended (DraI) double-stranded DNA breaks. It was found that the DNA-Pol reaction in MDS and HL60 cells corresponds to 3' recessed DNA fragments, the TdT reaction to 5' recessed and/or blunt ended fragments, and a combined "DNA Pol + TdT reaction" corresponds to a copresence of 3' recessed with 5' recessed and/or blunt ended fragments. Clearly, therefore, apoptotic DNA fragments, in spite of a unique length, may have differently staggered ends that could be cell (or tissue) specific and be selectively triggered by different inducers of apoptosis. The presence of TNF-alpha-inducible apoptotic DNA fragmentation pattern in MDS supports its involvement in these disorders and suggests that anti-TNF-alpha (or anticytokine) therapy may be of special benefit to MDS patients, where no definitive treatment is yet available.

Advances in epilepsy surgery

The history of epilepsy is probably as long as human race. It is estimated that 6-7% of population suffer at least one seizure at some time in their life, between 0.5-1% of Population suffer from active epilepsy. Drug treatment even when successful is only suppressive, since none of the drugs ls curative. Surgical approach, hence is more logical as it would eliminate the cause of the seizures. In pediatric age group, the need or early surgery is even greater as frequent seizure activity interferes with neuronal migration, leading to mental retardation.

For several years only small number of patients were offered surgery, however, advances in neuroimaging studies and development of new surgical techniques have enabled Us to deal with the lesion in the eloquent areas, without any major problem.

Apparent expansion of CD34+ cells during the evolution of myelodysplastic syndromes to acute myeloid leukemia

Myelodysplastic syndromes (MDS) are highly proliferative bone marrow (BM) disorders where the primary lesion presumably affects a CD34+ early progenitor or stem cell. We investigated the proliferative characteristics of CD34+ cells of 33 untreated MDS patients (19 RA, 5 RARS, 7 RAEB, 2 RAEBt) and five patients with acute myeloid leukemia after MDS (sAML). All patients received a 1-h infusion of the thymidine analogue iodoor bromodeoxyuridine intravenously before a BM aspirate and biopsy was taken. A double-labeling immunohistochemistry technique by monoclonal anti-CD34 (QBend/10) and anti-IUdR/BrdU antibodies was developed and performed. By this technique we recognised CD34+ and CD34- cells actively engaged in DNA synthesis or not. As MDS evolves a significant increase occurred in the percentage of CD34+ cells of all myeloid cells (mean value: RA/RARS 1.67%; RAEB(t) 8.68%; sAML 23.83%) as well as in the percentage of proliferating CD34+ cells of all myeloid cells (RA/RARS 0.19%; RAEB(t) 0.43%; and sAML 3.30%). This was associated with a decreasing trend in the overall myeloid labeling index (LI: RA/RARS 25.8%, RAEB(t) 24.6% and sAML 21.5%). This decrease in overall myeloid LI is due to an exponential increase in the proportion of CD34+ cells of the proliferating compartment during MDS evolution (RA/RARS 0.35%, RAEB(t) 1.44% and sAML 11.98% of all S-phase cells). These CD34+ cells appeared to proliferate more slowly than their more mature CD34 negative counterparts, since we found a progressive increment in the mean total cell cycling time (Tc) of all myeloid cells during MDS progression (RA/RARS 39.8, RAEB(t) 45.2 and sAML 65.8 h). This study showed that during MDS evolution to sAML the CD34+ compartment develops a growth advantage leading to apparent expansion.

Hypothesis: myelodysplastic syndromes may have a viral etiology

An 'initial transforming event(s)' in a pluripotential bone marrow (BM) stem cell confers a growth advantage upon it leading to clonal expansion accompanied by dysplastic maturation resulting in myelodysplastic syndromes (MDS). The nature of this 'initial' event in MDS is obscure. We propose that MDS can begin as a viral disease. It may be a dormant lentivirus which is made oncogenic by 'promoting events' such as immunosuppression, or a second viral infection. The infected cell may not be a BM stem cell, but a cell belonging to the BM stroma or to the immune system. Dysregulated cytokine production as a consequence of the infection can change the BM microenvironment in such a way that optimal growth support is provided only to a rapidly proliferating stem cell. Karyotypically marked (or unmarked) abnormal stem cells may exist or arise frequently but do not thrive in a 'normal' cytokine milieu. However, with the changed BM landscape, these abnormal clones may enjoy a growth advantage leading to a monoclonal hypercellular BM and variable cytopenias. Circumstantial evidence to support the possibility that the initial transforming event in MDS is a viral insult is presented in this hypothesis paper.

Endobrst: simple and safe is best

Minimal-access treatment for ureteropelvic junction (UPJ) obstruction is becoming increasingly complex. Is there still a place for the simple procedure of balloon dilatation? To examine the symptomatic and renographic results of patients at least 6 months after balloon disruption of an obstructed UPJ, we carried out a prospective audit of outcome as judged by DTPA renograms and clinical follow-up. The procedure has been performed on a total of 21 renal units (20 patients) with follow-up of 6 to 30 months (mean 22 months). Of these, 18 (86%) were asymptomatic at 3 months, although this success rate dropped to 17 (81%) by 6 months. Renographic split function improved in 11 renal units, and excretion improve in 14. Perioperative complications were few and associated with stent insertion. Three of the patients in whom the procedure failed went on to nephrectomy (14%); all had poor renal function (split <20%) at presentation. Although the quoted success rates are lower for endoluminal balloon rupture of stenosis treatment than open pyeloplasty, the former technique has significantly less morbidity. Our nephrectomy rate reflects our less than ideal early patient selection, and our balloon dilation technique is not recommended as a salvage procedure for patients in whom nephrectomy is inevitable. The learning curve is quick to climb, and this is a fundamentally simple procedure with medium-term results that remain encouraging.

Tumor necrosis factor-alpha levels decrease with anticytokine therapy in patients with myelodysplastic syndromes

Tumor necrosis factor-alpha (TNF-alpha) levels were measured in the serum (sTNF-alpha) or bone marrow (BM) biopsies of 43 patients with myelodysplastic syndromes (MDS) who subsequently received therapy with a combination of pentoxifylline and ciprofloxacin (PC) with or without dexamethasone (PCD). All 43 patients received only PC therapy for 12 weeks, after which 18 of 36 nonresponders received PCD. A total of 18 of 43 patients showed a hematologic or cytogenetic response or both. BM TNF-alpha levels were semiquantitatively assessed using immunohistochemistry on a scale of 0-8+ and in the serum using enzyme linked immunoassay. The median TNF-alpha for the entire group was 3.0 in BM and 6.9 pg/ml in the serum, and 14 patients had no detectable levels. Responders had higher BM levels (median 3.5 vs. 2.0) than nonresponders, although this was not statistically significant. During PC therapy, a decline in BM TNF-alpha level was seen in the entire group, which was significant at 2 weeks (p = 0.02), 8 weeks (p = 0.001), and 12 weeks (p = 0.0001). Both responders (p = 0.01) and nonresponders (p = 0.03) had a decline at 8 weeks, but at 12 weeks, only the responders continued to show a significant decline (p = 0.03). We conclude that MDS patients with high BM TNF-alpa levels have a better chance of responding to PCD therapy and that the therapy is quite successful in reducing the TNF-alpha levels in a sustained fashion. Future studies need to be directed at identifying agents that would be more potent suppressors of the proapoptotic cytokines in these patients.

Initial transforming event in myelodysplastic syndromes may be viral: case for cytomegalovirus

Myelodysplastic syndromes (MDS) are clonal hematopoietic disorders which begin in a pluripotential bone marrow (BM) stem cell. This early stem cell is believed to acquire a growth advantage over its neighbors as a result of an initial transforming event, the nature of which has remained obscure. In this paper, we propose that pathogens such as those belonging to the herpesvirus family of DNA viruses may play a role in the initial transformation of the stem cell. The case for cytomegalovirus (CMV) as a representative of this family of viruses is discussed at length and a molecular mechanism which may be involved in the oncogenic activity of CMV is proposed. No proof has been presented to implicate CMV directly in MDS, but circumstantial evidence which supports such a possibility is provided.

Local anesthesia for fine-needle aspiration biopsy of palpable breast masses: the effectiveness of a jet injection system

To determine the effectiveness of the Biojector 2000 needle-free lidocaine injection system in achieving satisfactory local anesthesia for fine-needle aspiration (FNA) of palpable breast lesions, we studied 29 female patients. Each patient served as her own control and had two FNA biopsies performed on the lesion. The first FNA biopsy was preceded by either no anesthesia, ethyl chloride cold spray, or traditional needle lidocaine injection. The second FNA was preceded by the Biojector 2000. Twenty-four patients (83%) reported that they preferred the Biojector 2000 over either no anesthesia, ethyl chloride spray, or needle and syringe lidocaine injection. The Biojector 2000 needle-free injection system is an effective and useful method of local anesthesia for FNA of palpable breast masses.

The effects of 13-cis retinoic acid and interferon-alpha in chronic myelogenous leukemia cells in vivo in patients

The effects of the administration of a 3-day course of 13-cis retinoic acid in combination with interferon a [RA/IFN] on the leukemia cells was measured in vivo in 43 patients with chronic myelogenous leukemia. The administration of RA/IFN was associated with a significant fall in the white blood cell count of patients with chronic-phase disease and with a fall in the percentage S-phase cells in CML patients regardless of the stage of their leukemia. In two thirds of the patients studied the administration of RA/IFN was also associated with an increase in marrow apoptosis. The cytokine combination also suppressed bcl-2 and myc expression in a minority of patients and such expression appears to be associated with response to a treatment regimen which includes RA/IFN. These studies are the first to directly assess the effects of the combination of RA/IFN on chronic myelogenous leukemia cells in vivo in patients. These effects, if seen in other malignant diseases, could account for the therapeutic benefit which has been associated with the administration of this combination of biological agents to patients with malignant disease.

Detection of hyperdiploid malignant cells in body cavity effusions by fluoresence in situ hybridization on ThinPrep slides

BACKGROUND

Benign body cavity effusions sometimes cannot be distinguished from malignant ones by conventional cytology. The authors performed fluorescence in situ hybridization (FISH) on ThinPrep slides using chromosome specific probes to see if hyperdiploid malignant cells could be detected in 20 body cavity effusions. The results were then compared with those of conventional cytology.

METHODS

A total of 20 body cavity effusions from 19 patients were studied using conventional cytology and FISH. Probes specific for chromosomes 3, 8, 10, and 12 were used to detect hyperdiploidy on ThinPrep slides (Cytyc Corporation, Boxborough, MA).

RESULTS

A total of 13 patients had malignant conditions (either prior history of malignancy or the presence of malignancy anywhere in the body). Conventional cytology and FISH were both positive in 5 of these patients (6 samples) and negative in 2 patients. The results for one sample were inconclusive by both methods. There were 5 discrepant cytology-FISH results in patients with malignant conditions. One sample was positive by FISH and negative by cytology, one was positive by FISH and "atypical" by cytology, and three were inconclusive by FISH and negative by cytology. FISH results were either negative (in 4 samples) or inconclusive (in 2 samples) in the 6 patients with benign conditions.

CONCLUSIONS

FISH can detect hyperdiploid malignant cells in body cavity effusions and is especially useful when the major cell population consists of malignant cells that cannot be differentiated from mesothelial or "atypical" cells. It is less useful in detecting a small population of malignant cells hidden in an inflammatory or reactive cell background. More studies are needed to establish diagnostic criteria further and to assess the clinical usefulness of this procedure.

Excessive proliferation matched by excessive apoptosis in myelodysplastic syndromes: the cause-effect relationship

The paradox of pancytopenia despite cellular bone marrows (BM) was investigated in 120 patients with myelodysplastic syndromes (MDS). Detailed cell cycle kinetics were examined following in vivo infusions of iodo--and/or bromodeoxyuridine (IUdR/BrdU), while the incidence of apoptosis was measured by in situ end labeling (ISEL) of fragmented DNA. Results showed that MDS are highly proliferative disorders with an equally high incidence of apoptotic intramedullary cell death accounting for the paradox of cellularity/cytopenia. By double-labeling BM biopsy sections for ISEL/BrdU we found the peculiar situation of "signal antonymy" where S-phase cells were frequently apoptotic, a phenomenon so far only seen in MDS biopsies. The cause-effect relationship of this excessive proliferation/apoptosis is discussed at length.

Cell cycle kinetic studies in 68 patients with myelodysplastic syndromes following intravenous iodo- and/or bromodeoxyuridine

Sixty-eight patients with myelodysplastic syndromes (MDS) received sequential infusions of iodo- and/or bromodeoxyuridine for cell kinetic analysis. Bone marrow biopsy sections were treated by appropriate antibodies and a labeling index (LI), duration of S-phase (Ts), and total cell cycle time (Tc) of myeloid cells were determined. The mean LI was 28.4%, Ts was 11.8 hours and Tc was 40.7 hours. The %LI decreased as the disease evolved from refractory anemia toward transformation to acute leukemia (p = 0.04). Double-labeling of biopsy sections for apoptosis and proliferation showed that 30-90% of S-phase cells in MDS patients were simultaneously apoptotic or "antonymous." We conclude that MDS are highly proliferative disorders in which the ineffective hematopoiesis is probably the result of excessive apoptosis rather than slow proliferation.

Bcl-2 and c-myc expression, cell cycle kinetics and apoptosis during the progression of chronic myelogenous leukemia from diagnosis to blastic phase

Chronic myelogenous leukemia (CML) has a progressive course but little is known about the biologic characteristics of disease progression. This study was designed to assess the changes in cell proliferative characteristics, apoptosis, the expression of the bcl-2 and c-myc genes between the time of initial diagnosis and entrance into the blastic phase of the disease. We observed that the rate of cell proliferation decreased and the cell death rate did not significantly change as the disease accelerated. The level of bcl-2 expression was significantly higher in accelerated/blastic phase cells than in the chronic phase cells in the population as a whole, however, the bcl-2 expression level did not change in blast cell subpopulation. c-myc Expression was significantly higher in the blast cell subpopulation of accelerated/blastic phase than in that of earlier phases of the disease. In conclusion, the characteristics of CML cells, namely proliferation rate, c-myc and bcl-2 change during the course of the disease. It is possible that the change in c-myc expression plays a causative role in evolution of the blastic phase from the chronic phase.

Cytokines, molecular biological abnormalities, and acute myelogenous leukemia

Leukemia cell proliferation is dependent upon cytokines produced by the leukemia cells or by the microenvironment under stimulation by leukemia cells. Abnormal expression of the p53, rb, and ras genes is associated with cytokine production, suggesting that abnormal expression can affect leukemia cells by affecting intracellular growth controls and by stimulating cytokine production. While these observations suggest that cytokines can be used to stimulate leukemia proliferation during cytotoxic therapy increasing the sensitivity to treatment, they also suggest that inhibition of cytokine affects could increase clinical responses by reducing leukemia cell regrowth between courses of therapy.

Regrowth resistance as a likely significant contributor to treatment failure in drug-sensitive neoplastic diseases

Attempts to improve the effectiveness of therapy for neoplastic diseases have largely focused on increasing the cytotoxic efficacy of therapy. While this approach is logical, there is another approach, based on the concept of regrowth resistance, which offers an alternate means of improving treatment outcome. The term "regrowth resistance" refers to the reduction in treatment efficacy resulting from the regrowth of neoplastic cells between courses of therapy or even between doses of radiation therapy. Regrowth resistance is likely to play a significant role in determining the outcome of treatment in rapidly proliferating neoplasms. A reduction in the rate of tumor regrowth would increase the net effectiveness of cytotoxic therapy and would also inhibit the development of resistance to cytotoxic therapies.

The myelodysplastic syndromes in 1996: complex stem cell disorders confounded by dual actions of cytokines

Based upon recent studies of apoptosis, proliferation, cytokines and genic abnormalities, a new hypothesis regarding the pathology of myelodysplastic syndromes is being proposed. The transforming abnormality which affects an early progenitor hemopoietic stem cell is poorly defined so far but confers a growth advantage on this cell eventually leading to monoclonal hemopoiesis at least affecting the non-lymphoid bone marrow cells. Several cytokines confound the picture by exerting dual effects of stimulating the proliferation of immature cells while inducing the apoptosis in their maturing progeny thereby producing the clinical syndrome of cytopenias despite cellular marrows. Since a number of these offending cytokines share the same common lipid intracellular signalling pathway, interfering with the generation of specific phospholipid second messengers should hypothetically result in a dual effect as well. Alleviation of cytopenias (due to attenuation of apoptosis) should be accompanied by a decrease in the progeny of the transformed stem cell (due to suppression of proliferation) eventually allowing for resumption of polyclonal hemopoiesis.

Measurement of apoptosis, proliferation and three cytokines in 46 patients with myelodysplastic syndromes

Extensive apoptosis or programmed cell death (PCD) of both hematopoietic (erythroid, myeloid, megakaryocytic) and stromal cells in myelodysplastic syndromes (MDS) cancels the high birth-rate resulting in ineffective hematopoiesis and has been demonstrated as the probable basis for peripheral cytopenias in MDS by our group. It is proposed that factors present in the microenvironment are inducing apoptosis in all the cells whether stromal or parenchymal. To investigate this hypothesis further, bone marrow biopsies from 46 MDS patients and eight normal individuals were examined for the presence of three cytokines, tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta) and granulocyte macrophage-colony stimulating factor (GM-CSF) and one cellular component, macrophages, by the use of monoclonal antibodies immunohistochemically. Results showed the presence of TNF-alpha and TGF-beta in 41/46 and 40/46 cases of MDS respectively, while only 15 cases showed the presence of GM-CSF. Further a significant direct relationship was found between the degree of TNF-alpha and the incidence of PCD (p= 0.0015). Patients who showed high PCD also had an elevated TNF-alpha level. Thus, the expression of high amounts of TNF-alpha and TGF-beta and low amounts of the viability factor GM-CSF may be responsible for the high incidence of PCD leading to ineffective hematopoiesis in MDS. Future studies will be directed at attempting to reverse the lesion in MDS by using anti-TNF-alpha drugs such as pentoxifylline.

Indication of an involvement of interleukin-1 beta converting enzyme-like protease in intramedullary apoptotic cell death in the bone marrow of patients with myelodysplastic syndromes

Our previous studies using in situ end labeling (ISEL) of fragmented DNA revealed extensive apoptotic cell death in the bone marrows (BM) of patients with myelodysplastic syndromes (MDS) involving both stromal and hematopoietic cells. In the present report we show greater synthesis of interleukin-1 beta (IL-1 beta) in 4 hour cultures of density separated BM aspirate mononuclear (BMAM) cells from MDS patients as compared to the cultures of normal BM from healthy donors or lymphoma patients (1.7 +/- 0.37 pg/10(5) cells, n = 29 v 0.42 +/- 0.24 pg/10(5) cells, n = 11, respectively, P = .049). Further, these amounts of IL-1 beta in MDS showed a significant correlation with the extent of apoptosis detected by ISEL in corresponding plastic embedded BM biopsies (r = .480, n = 30, P = .007). In contrast normal BMs did not show any correlation between the two (r = .091, n = 12, P = .779). No significant correlation was found between the amounts of IL-1 beta and % S-phase cells (labeling index; LI%) in MDS determined in BM biopsies using immunohistochemistry following in vivo infusions of iodo- and/or bromodeoxyuridine. Neither anti-IL-1 beta antibody nor IL-1 receptor antagonist blocked the apoptotic death of BMAM cells in 4 hour cultures (n = 5) determined by ISEL (apoptotic index; AI%), although the latter led to a dose-dependent accumulation of active IL-1 beta in the culture supernatants. On the other hand, a specific tetrapetide-aldehyde inhibitor of ICE significantly retarded the apoptotic death of BMAM cells at 1 mumol/L in 5/6 MDS cases studied (AI% = 2.99 +/- 0.30 in controls v 1.58 +/- 0.40 with ICE-inhibitor, P = .05) and also reduced the levels of active IL-1 beta synthesized (5.59 +/- 2.63 v 2.24 +/- 0.93 pg/10(6) cells, respectively). In normal cells, neither IL-1 blockers nor the ICE inhibitor showed any effect on the marginal increase in apoptosis observed in 4 hour cultures. Our data thus suggest a possible involvement of an ICE-like protease in the intramedullary apoptotic cell death in the BMs of MDS patients.

A paradigm shift in myelodysplastic syndromes

A poorly defined transforming event(s) affects the pluripotential bone marrow (BM) stem cell in myelodysplastic syndromes (MDS), conferring a growth advantage upon it which leads eventually to monoclonal hematopoiesis. The progeny of this transformed ancestor undergo recognizable albeit dysplastic maturation. We propose that this picture is further complicated by a variety of cytokines, tumor necrosis factor alpha (TNF-alpha), transforming growth factor beta (TGF-beta) and interleukin 1beta (IL-1beta) which exert a dual effect on the diseased cells. The immature CD34+ cells are stimulated to proliferate, while their later differentiated daughters are induced to undergo apoptosis accounting for the clinical syndrome of pancytopenia despite hypercellular BMs. Studies directed at measuring the rates of proliferation and apoptosis as well as the levels of TNF-alpha, TGF-beta and IL-1beta confirm this hypothesis and are presented in greater detail. A novel approach towards MDS therapy emerges as a result of this paradigm shift based upon the premise that anti-cytokine therapy would prevent excessive intramedullary apoptosis and result in improved cytopenias as well as cause a slowing down of the diseased precursor cell proliferation resulting in resumption of polyclonal hematopoiesis. Because a number of cytokines function through common lipid second messengers, interruption of this pathway should theoretically cause disruption in the signalling of a cascade of cytokines.

Novel insights into the biology of myelodysplastic syndromes: excessive apoptosis and the role of cytokines

The paradox of myelodysplastic syndromes (MDS) which present with pancytopenias despite cellular bone marrows (BM) was investigated by conducting detailed studies of proliferation and apoptosis in 89 MDS patients. Our results demonstrated a rapid rate of both proliferation as well as apoptosis. Levels of three cytokines, tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta) and interleukin-1 beta (IL-1 beta) were measured in the same patients. High levels of TNF-alpha were found to correlate with high levels of apoptosis in 83 MDS patients (P = 0.0045). We propose a dual role for TNF-alpha (or other cytokines) in the pathogenesis of MDS. On the one hand, TNF-alpha induces apoptosis in the maturing cells causing pancytopenia while on the other, it stimulates the proliferation of the primitive progenitors accounting for the hypercellular BM frequently seen in MDS. A new model for MDS is presented. The initial abnormality probably affects a primitive hemopoietic progenitor which acquires a growth advantage leading to monoclonal hemopoiesis, which in turn makes these cells susceptible towards acquiring additional mutations and appearance of cytogenetically marked (or unmarked) clones. Cytokines such as TNF-alpha whose source is presently unknown, then contribute towards the clinical syndrome of pancytopenia and hypercellularity.

Assessment of apoptosis in relation to proliferation and mutational status of p53 gene in head and neck cancers

The present studies were undertaken to determine the incidence of apoptosis in plastic embedded head and neck (HN) tumor biopsies (n=31) using in situ end labeling (ISEL) of fragmented DNA. The extent of spontaneous apoptosis in untreated tumors was correlated with histological grade, percent S-phase cells (Labeling Index, LI) and with the mutational status of p53 gene in these tumors. Additionally, the in vivo effects of chemo- and/or radiotherapy on apoptosis were evaluated in seven patients. In the majority of tumors studied (25/31) spontaneous apoptosis was virtually undetectable or was very low (1-15% positively labeled cells). Only 6 tumors showed intermediate to high apoptosis (>15% positively labeled cells). High apoptosis was more frequent in poorly differentiated tumors (similar to 50%), as compared to well and moderately differentiated tumors. The median LI for 31 tumors studied was 20.2%. The mean LI for moderately differentiated tumors (23.7+/-1.7%) was significantly higher than that in well differentiated (15.1+/-2.1%, p=0.005) and was comparable in poorly differentiated tumors (24.5%). Cytotoxic therapy significantly increased the degree of apoptosis in 5/7 specimens studied (p=0.03). Double labeling of 5 of these tumors before and after the therapy, combining ISEL with detection of IUdR/BrdU, showed compartmentalized apoptosis and proliferation with virtually no double labeled cells in any specimen. Interestingly, tumors with a mutated p53 gene (n=6) showed intermediate to high degree of pretherapy, baseline apoptosis in contrast to low or undetectable levels of apoptosis in tumors bearing wild-type p53 (n=13, p=0.034). It appears that low levels of apoptosis and high proliferation may be characteristic of HN tumors. The spontaneous apoptosis in HN tumors seems unrelated to mutations in the p53 gene. Moreover, our data also show that despite overall increase in apoptosis induced by cytotoxic therapy, some proliferating tumor cells escaped the effects of therapy, which may contribute to the tumor relapse.

Enzymatic programming of apoptotic cell death

The phenomenon of 'apoptosis' was recognized in the early seventies. However, most of the mechanistic insights into the process of apoptotic cell death came about only in the last few years. It is now clear that a variety of enzymes constitute the major mediators of this process. The present article reviews the possible interrelationships between these enzymes and proposes a model for enzymatic programming of apoptotic cell death.

Fibroblasts isolated after fibrotic lung injury induce apoptosis of alveolar epithelial cells in vitro

Primary lung fibroblasts were isolated from patients with idiopathic pulmonary fibrosis (HIPF), from normal human lung tissue (NH), from rats treated with 75% oxygen and paraquat (PA), and from normal adult rats (NR). Serum-free media conditioned by each fibroblast strain were tested on the human A549 cell line (HIPF and NH media) or on primary alveolar epithelial cells (AEC) isolated from normal adult rats (PA or NR media). Over 20-h incubation, HIPF- or PA-conditioned media induced DNA fragmentation and significant decreases in total recoverable DNA and cell number of A549 or AEC, respectively; NH or NR media had no significant effect relative to serum-free unconditioned media. Apoptosis of A549 and AEC was detected by altered nuclear morphology and was confirmed by terminal deoxynucleotidyl transferase-mediated bio-dUTP nick end labeling. The endonuclease inhibitors 10 microM aurintricarboxylic acid and 50 microM zinc inhibited HIPF-induced apoptosis of A549 cells by 68 and 71%, respectively. Both apoptosis and necrosis were induced by HIPF and PA media in a concentration-dependent manner. These results suggest that altered fibroblasts emerging during fibrotic lung injury release a soluble factor(s) capable of inducing cell death and net loss of AEC.

Distribution of cell cycle times amongst the leukemia cells within individual patients with acute myelogenous leukemia

Seventeen patients with AML received infusions of BrdUrd to permit measurement of the cell parameters of leukemia cells in vivo. The range of S-phase times was measured by using a two color BrdUrd/Pl analysis to determine the range of BrdUrd incorporation into cells which had been in S-phase throughout the entire duration of BrdUrd administration. These data were, in turn, used to calculate the range of cell cycle times amongst the leukemia cells present within individual patients. The range of cell cycle times amongst the leukemia cells present within individual patients differs between patients, with some leukemia cell populations characterized by narrow and others by broad ranges. In general, the longer the mean cell cycle time (between 27 and 112 h) the broader the range of cell cycle times. These differences may help to explain, in part, the differences in response to therapy among patients whose mean leukemia cell kinetic parameters are similar.

Two in situ labeling techniques reveal different patterns of DNA fragmentation during spontaneous apoptosis in vivo and induced apoptosis in vitro

BACKGROUND

Two new enzymatic reactions were described recently to detect apoptotic cell death in situ viz in situ end labeling (ISEL) and terminal deoxynucleotidyl transferase mediated UTP nick end labeling (TUNEL) of fragmented DNA. A comparative study was conducted to detect in vivo and in vitro apoptotic death using these two techniques. Experimental design; Spontaneous apoptous cell death was detected in plastic embedded tumor biopsies from patients with non-Hodgkin's lymphoma (NHL), head and neck squamous cell carcinomas (HNSCC), and breast cancer using these two in situ methods. Uninvolved normal tissues adjacent to breast tumors and a lymph node metastasis of breast tumor were also studied. Furthermore, apoptotic death induced by different doses of etoposide (VP16) was also studied in HL60 cells by in situ methods and by agarose gel electrophoresis.

RESULTS

Interestingly, whereas NH1 and HNSCC biopsies showed comparable levels of detectability with the two techniques, the breast tissues be it neoplastic, normal or metastatic, revealed apoptosis detectable only by TUNEL and not by ISEL. Similarly in HL60 cells, the percentage of apoptotic cells or apoptotic index (AI) determined by TUNEL was significantly higher than that determined by ISEL. A double labelling of these HL60 cells for ISEL and TUNEL also revealed a higher proportion of cells labeled positively for TUNEL as compared to those labeled for ISEL. Agarose gel electrophoresis revealed characteristic DNA laddering only at 35 microM dose of VP 16. No smearing of DNA was found in any group ruling out the necrotic death. In vivo, in one HNSCC specimen apoptosis and necrosis could be differentiated by the difference in staining intensity. Both methods stained necrotic chromatin fragments very lightly. The DNA fragments generated during apoptosis could be of unique lengths (ie 180-200 bp or multiples) but have differently staggered ends. These fragments may be 3' recessed, 5' recessed or blunt ended. While TUNEL can label all three types, ISEL labels only those with 3' recessed ends.

CONCLUSIONS

Thus our data show that the DNA fragments formed during spontaneous apoptosis in breast tissues and preferentially during VP16 induced apoptosis in HL60 cells are either 5' recessed or blunt ended, being distinctly different from 3' recessed fragments seen in NHL and HNSCC or with a lesser frequency in VP 16 treated HL60 cells. Specific fragmentation patterns could be a result of activation of different endonucleases which as indicated by our data could be tissue specific and may be differentially activated by different chemotherapeutic agents. Therefore, screening for the presence of specific endonucleases in different tissues and for agents specifically activating them would have major clinical implications.