Gray matter textural heterogeneity as a potential in-vivo biomarker of fine structural abnormalities in Asperger syndrome.

Brain imaging studies contribute to the neurobiological understanding of Autism Spectrum Conditions (ASC). Herein, we tested the prediction that distributed neurodevelopmental abnormalities in brain development impact on the homogeneity of brain tissue measured using texture analysis (TA; a morphological method for surface pattern characterization). TA was applied to structural magnetic resonance brain scans of 54 adult participants (24 with Asperger syndrome (AS) and 30 controls). Measures of mean gray-level intensity, entropy and uniformity were extracted from gray matter images at fine, medium and coarse textures. Comparisons between AS and controls identified higher entropy and lower uniformity across textures in the AS group. Data reduction of texture parameters revealed three orthogonal principal components. These were used as regressors-of-interest in a voxel-based morphometry analysis that explored the relationship between surface texture variations and regional gray matter volume. Across the AS but not control group, measures of entropy and uniformity were related to the volume of the caudate nuclei, whereas mean gray-level was related to the size of the cerebellar vermis. Similar to neuropathological studies, our study provides evidence for distributed abnormalities in the structural integrity of gray matter in adults with ASC, in particular within corticostriatal and corticocerebellar networks. Additionally, this in-vivo technique may be more sensitive to fine microstructural organization than other more traditional magnetic resonance approaches and serves as a future testable biomarker in AS and other neurodevelopmental disorders.

Pion cancer therapy: positron activity as an indicator of depth-dose.

Negative pions are useful for radiation therapy of localized carcinoma because of their large end-of-range energy deposition upon capture in nuclei and the potentially accurate spatial localization of the radiation dose. Accurate determination of the depth of penetration of the pion beam in vivo can be accomplished by counting the back-to-back annihilation gamma rays resulting from positron activity induced by the stopped pions.

Reversal of adriamycin resistance by verapamil in human ovarian cancer.

The effectiveness of adriamycin in the treatment of ovarian cancer and other human tumors has been limited by the development of drug resistance. Verapamil, a calcium channel blocking agent, completely reversed adriamycin resistance in human ovarian cancer cells with moderate (three- to sixfold) degrees of resistance and partially reversed resistance in highly (150-fold) resistant cells. The potentiating effect of verapamil was due to inhibition of adriamycin efflux in the resistant cells. These results have led to a clinical trial of adriamycin and verapamil in refractory ovarian cancer patients.

Adriamycin: the role of lipid peroxidation in cardiac toxicity and tumor response.

The antitumor antibiotic, adriamycin, induces severe cardiac toxicity associated with peroxidation of cardiac lipids in mice. Both this lipid peroxidation and cardiac toxicity of adriamycin are reduced by prior treatment of the animals with the free radical scavenger tocopherol. Such treatment with tocopherol does not, however, alter the magnitude or duration of the adriamycin-induced suppression of DNA synthesis in P388 ascites tumor, nor does it diminish the antitumor responsiveness of P388 ascites tumor. These results suggest that adriamycin has at least two mechanisms of tissue damage: one, which involves lipid peroxidation, is blocked by tocopherol and results in cardiac toxicity; the other, which involves binding to DNA, is not antagonized by tocopherol and is responsible for tumor response.

Threshold methotrexate concentration for in vivo inhibition of DNA synthesis in normal and tumorous target tissues.

The suppression of DNA synthesis in host and tumor tissues by methotrexate has been monitored in mice by determining the in vivo incorporation of tritium-labeled deoxyuridine ([(3)H]UdR) into DNA. The duration of inhibition of [(3)H]UdR incorporation in normal tissues was related to the dose of methotrexate and was a direct function of plasma drug concentration. [(3)H]UdR incorporation recovered to 50% of pretreatment levels in bone marrow when plasma methotrexate concentration was 10(-8) M or less, irrespective of the dose administered, while 50% recovery of DNA synthesis in intestinal epithelium was not observed until plasma methotrexate levels were 5 x 10(-9) M or less. Ascitic L1210 leukemia cells did not fully return to pretreatment levels of [(3)H]UdR incorporation at any time, although a partial recovery of incorporation was noted at methotrexate ascitic fluid concentrations of approximately 10(-8) M. Methotrexate did not suppress the incorporation of tritium-labeled thymidine ([(3)H]TdR) into bone marrow and duodenal mucosa, confirming the specificity of its action in inhibiting thymidylate synthesis in host tissues. In the ascites tumor a gradual decline in [(3)H]TdR incorporation was seen after methotrexate, indicating that the tumor tissue depression of [(3)H]UdR incorporation is not solely due to inhibition of thymidylate synthesis. These studies indicate that host tissues are inhibited by extremely low concentrations of methotrexate, and indicate the importance of the slow final phase (t((1/2))=12 h) of drug elimination from plasma in producing a prolonged exposure of sensitive host tissues to inhibitory drug concentrations.

Biochemical determinants of 5-fluorouracil response in vivo. The role of deoxyuridylate pool expansion.

5-Fluorodeoxyuridine monophosphate (FdUMP), the active metabolite of 5-fluorouracil (5-FU), is a tight-binding inhibitor of thymidylate synthetase, the enzyme which converts dUMP to TMP. Newly developed assays for FdUMP and dUMP were utilized to assess the competitive roles played by these nucleotides in determining the inhibition of TMP synthesis in mice bearing the P1534 ascites tumor. After 5-FU administration, levels of FdUMP reached a dose-dependent peak within 6 h in the ascites tumor and in bone marrow, and declined thereafter in a biphasic manner with an initial t 1/2 of 6 h and a final t 1/2 of 7-9 days. In duodenal mucosa, FdUMP levels were 1.8-2-fold higher than in the other tissues, but elimination was much more rapid. Simultaneous with the fall in FdUMP a progressive accumulation of the competitive substrate dUMP was observed in each tissue after 5-FU; and peak dUMP levels coincided with recovery of thymidylate synthesis, as determined by the incorporation of [3H]deoxyuridine into DNA. In vitro experiments with partially purifed thymidylate synthetase revealed and initial competitive interaction of dUMP and FdUMP, which, at high concentrations of dUMP was capable of markedly slowing the rate of irreversible inactivation of enzyme by FdUMP. These studies were found to be quantitatively consistent with a two-phase model of enzyme inactivation involving an initial competition between dUMP and FdUMP, with subsequent irreversible inactivation of enzyme by covalent linkage to the inhibitor. Recovery of thymidylate synthesis after 5-FU appears to result from both a fall in intracellular levels of inhibitor and a progressive accumulation of the competitive substrate dUMP.

Cognitive impairment in bipolar disorder in old age: literature review and findings in manic patients.

BACKGROUND: Descriptions of aged patients with bipolar (BP) disorder have commented on cognitive impairments. However, the literature regarding cognitive test performance in this population has apparently been scant. METHOD: 1. We reviewed studies reporting cognitive performance in aged BP patients. 2. We compared the performance of elderly BP manic patients and aged community comparison subjects on the Mini-Mental State Examination (MMSE) and the Mattis Dementia Rating Scale (DRS). RESULTS: 1. Seven published studies of cognitive measures in aged BP patients were identified. They utilized different assessment methods and addressed different illness states, but they indicate impairments in these patients. 2. In our sample, the manic patients (n=70) had lower MMSE scores and DRS scores than did the comparison subjects (n=37). In these patients, cognitive scores were not significantly associated with Mania Rating Scale scores. LIMITATIONS: The patients in our study were assessed cross-sectionally, and they were treated naturalistically. CONCLUSIONS: Manic or depressed BP elders have impaired cognitive function; in some patients these impairments may persist. Research characterizing these impairments and their clinical implications is warranted.

Effect of glutathione on DNA repair in cisplatin-resistant human ovarian cancer cell lines.

We have studied the effect of glutathione reduction by buthionine sulfoximine (BSO), a specific inhibitor of gamma -glutamyl cysteine synthetase, on DNA repair after cisplatin damage in an ovarian cancer cell line with in vitro induced resistance to cisplatin. In addition, we have examined the effect of aphidicolin, a specific inhibitor of DNA polymerase alpha, in combination with BSO on cisplatin-associated DNA repair. BSO treatment was found to partially inhibit DNA repair, and the addition of aphidicolin caused nearly a 100% inhibition in DNA repair activity. Treatment of cells with glutathione ester after BSO resulted in complete recovery of DNA repair activity or partial recovery if aphidicolin was present. The significance of these results to the chemosensitizing effects of BSO medicated glutathione reduction is discussed.

Second primary neoplasms following ovarian cancer.

Follow-up surveys of patients with ovarian cancer revealed an increased risk of second primary cancers of the uterine corpus, colon, bladder, breast, and hematopoietic system. The excess risk or uterine corpus cancer was independent of therapy. The risk of colon cancer was increased in all treatment groups but was especially high among patients receiving radiation or chemotherapy. The predisposition to other neoplasms was limited to certain treatment groups: bladder cancer to irradiation, leukemia to chemotherapy, and lymphoma to either modality. The pattern of second neoplasms following ovarian cancer appears to be influenced by therapy as well as by common etiologic factors.

High-dose carboplatin with diethyldithiocarbamate chemoprotection in treatment of women with relapsed ovarian cancer.

Diethyldithiocarbamate (DDTC) has been found to protect the bone marrow, kidneys, and gastrointestinal tract from the toxic effects of cisplatin and carboplatin (CBDCA) in animal models. In an attempt to minimize the toxic effects of high-dose CBDCA (800 mg/m2), a pilot study was undertaken in which women with relapsed or refractory epithelial ovarian cancer were treated with high-dose CBDCA, which was followed 3 hours later with DDTC (4 g/m2). There were four partial responses and no complete response in 21 patients who could be evaluated (overall response rate, 19%). Significant toxic effects, including three treatment-related deaths, were associated with the regimen. This study suggests that while high-dose CBDCA plus DDTC may be active in relapsed or refractory ovarian cancer, it is associated with clinically significant hematologic and autonomic toxic effects.

Adriamycin-induced cardiac damage in the mouse: a small-animal model of cardiotoxicity.

After one dose of adriamycin, a subacute cardiomyopathy was observed in the mouse by both light and electron microscopy. The microscopic alterations were characterized by single-cell necrosis and mitochondrial degeneration. These lesions were similar to those seen in man and shortly preceded fatal toxicity.

Cytogenetic studies in human T-cell lymphoma virus (HTLV)-positive leukemia-lymphoma in the United States.

Cytogenetic studies were conducted on fresh and cultured cells from 11 patients with human T-cell leukemia virus-associated adult T-cell leukemia-lymphoma. Clones with abnormal karyotypes were detected in 9 of the 11 patients. Chromosome numbers were near-diploid in cells from all but 1 patient who also had a tetraploid clone. The chromosome abnormalities in these cells were extensive; numerous complex structural changes were seen in every chromosome pair. Structural abnormalities occurred most frequently in chromosome 6. The 6 patients with chromosome 6 deletions had breakpoints at bands q11, q13, q16q23, q21q23, q22q24, and q23q24. The characteristic clinical features of these 6 patients were aggressive course, short survival, poor response to chemotherapy, high white blood cell counts, hypercalcemia, and bone lesions, whereas cytogenetically abnormal patients without chromosome 6q deletions tended to have a more indolent course. The precise role of the 6q deletion cannot be established with certainty from these data. However, this abnormality appears to occur with a greater than expected frequency in this large cell aggressive lymphoma, in association with hypercalcemia and lytic bone lesions.

Deletion of 3(p14p23) in secondary erythroleukemia arising in long-term survivors of small cell lung cancer.

Cytogenetic studies were done on the leukemia cells of two patients with small cell lung cancer (SCLC) who developed erythroleukemia (acute nonlymphocytic leukemia, French-American-British M6) after combined modality chemotherapy and radiotherapy for their lung cancer. Surprisingly, both erythroleukemias exhibited the del(3)(p14p23) predominantly found in SCLC. In four other patients who had secondary erythroleukemias associated with other cancers, no deletions of 3p were found. These findings could be accounted for by one of three possible mechanisms: (a) an inherited recessive gene (anti-oncogene or tumor suppressor gene) in this region of 3p was uncovered by the combined modality therapy, (b) an inherited predisposition to damage of both chromosomes at 3p14 leads to SCLC and erythroleukemia after exposure to carcinogens and/or chemotherapy-radiotherapy, or (c) the finding of lineage specificity for the 3p deletion with the presence of the 3p deletion in SCLC and erythroleukemia suggests a common bone marrow precursor.

Inhibition and recovery of DNA synthesis in host tissues and sensitive and resistant B16 melanoma after 1-(2-chloroethyl)-3-(trans-4-methylcyclohexyl)-1-nitrosourea, a predictor of therapeutic efficacy.

Single doses of 1-(2-chloroethyl)-3-(trans-4-methylcyclohexyl)-1-nitrosourea caused transient suppression of [3H]thymidine incorporation into DNA in bone marrow and gastrointestinal mucosa and more prolonged inhibition of such incorporation in B16 melanoma. A single dose of 1-(2-chloroethyl) -3- (trans-4-methylcyclohexyl) -1-nitro-sourea, 16 mg/kg, doubled the mean life-span after treatment of C57BL times DBA/2F1 male mice bearing 12-day-old B16 melanomas. Subsequent doses timed to minimize toxicity and maximize antitumor effect, however, produced no further prolongation of survival, and studies with B16 melanoma previously expsed to 1-(2-chloroethyl)-3-(trans-4-methylcyclohexyl)-1-nitrosourea demonstrated that the suppression of [3H]thymidine incorporation into DNA was no longer prolonged beyond that seen with normal host tissues. The loss of clinical efficacy was accompanied by a loss of differential suppression of [3H]thymidine incorporation into DNA between the tumor and host tissues.

Kinetic alterations induced by 5-fluorouracil in bone marrow, intestinal mucosa, and tumor.

In order to provide a more rational approach to the design of chemotherapeutic programs involving 5-fluorouracil (5-FU), the kinetic effect of this drug on bone marrow, gastrointestinal epithelium, and tumorous tissues in mice was monitored by determining the rate of incorporation of labeled deoxyuridine (UdR) into DNA following doses of 15, 50, and 100 mg/kg i.p: In BALB/c x DBA/2 F1 (hereafter called CD2F1) mice bearing P1534 ascites tumor, the magnitude and duration of suppression of [3H]UdR incorporation into DNA were directly related to drug dose for both the normal and tumorous tissues. However, the impact of 5-FU was clearly greater upon the P1534 ascites tumor than on either normal tissue, so that, after a dose of 100 mg/kg, the tumor did not initiate recovery until Day 5, while duodenal mucosa and bone marrow returned to 50% of control levels of UdR incorporation at 2 and 3 days, respectively. In order to determine whether the duration of suppression of [3H]UdR incorporation, such as observed in the P1534 ascites tumor, correlated with sensitivity of Ehrlich ascites tumor to 5-FU, the effect of 50 and 100 mg/kg of 5-FU i.p. on this less 5-FU-sensitive tumor was determined. No difference was observed in the time course of suppression and recovery between Ehrlich ascites tumor and the duodenal mucosa and bone marrow of the G.P. Swiss host. In non-tumor-bearing CD2F1 mice, the toxicity of a 2nd dose of 100 mg/kg 5-FU i.p. was found to be predictably related to the kinetic effect of a 1st dose of 100 mg/kg on [3H]UdR incorporation in the bone marrow and duodenal mucosa. In the time period from 12 hr through Day 6, when [3H]UdR incorporation into DNA rose to a maximum, administration of a 2nd dose of 5-FU was associated with 95% lethality. In contrast, during the period between 0 and 12 hr that preceded recovery of UdR incorporation, a 2nd dose resulted in less than 40% lethality, and, in the period from Day 6 through Day 8, when UdR incorporation was declining, lethality of a 2nd dose also declined to less than 25% lethality. In addition, the antitumor effectiveness of a 2nd dose of 5-FU, 100 mg/kg i.p., was predictably related to the differential effect of the 1st dose of 100 mg/kg on [3H]UdR incorporation in the P1534 tumor as compared to the host bone marrow and duodenal mucosa. Administration of a 2nd dose of 5-FU was maximally effective on Day 7, at a time when [3H]UdR incorporation was declining in the host target tissues and increasing to a maximum in the P1534 ascites tumor. Thus, the present study has demonstrated that [3H]UdR incorporation into DNA may be used to monitor the differential effect of 5-FU on tumor versus normal proliferating host tissues and, where such differences exist, to provide an in vivo method of value in designing a schedule of optimum therapeutic benefit.

Evidence of a treatment dose response in acute nonlymphocytic leukemias which occur after therapy of non-Hodgkin's lymphoma.

We evaluated the occurrence of second cancers among 517 patients with non-Hodgkin's lymphoma (NHL) treated at the National Cancer Institute. Nine cases of acute nonlymphocytic leukemia (ANL) were observed compared to 0.08 cases expected (ratio of observed to expected cases, 105; 95% confidence limits, 48; 199). The excess risk of ANL was 4.1 cases per 1000 patients per year; the cumulative risk of ANL at 10 years was 7.9 +/- 3.2% (S.E.). A case-control study within the NHL cohort revealed that patients treated with both radiation and chemotherapy were at greater risk of ANL than were patients who received single-modality therapy (relative risk, 6.0; p less than 0.05), especially if the therapy included total-body or hemibody radiation. A positive correlation between cumulative radiation dose to the bone marrow and risk of ANL was demonstrated, independent of chemotherapy duration. A similar correlation between chemotherapy dose and risk of ANL was suggested but could not be proven with the available data. An apparent association between ANL risk and indolent NHL histological subtypes was due to the significantly larger amounts of potentially leukemogenic therapy to which these patients were repeatedly exposed. Only one case of ANL occurred among NHL patients whose initial therapy produced a durable complete remission. Our data are compatible with a multistep model of leukemogenesis and also underscore the need for curative NHL treatment regimens which minimize the duration and quantity of therapy required for optimum patient management.

Characterization of a xenograft model of human ovarian carcinoma which produces ascites and intraabdominal carcinomatosis in mice.

We have used in vivo and in vitro procedures to select a subpopulation of cells from the human ovarian carcinoma cell line, NIH:OVCAR-3, with the capacity to grow i.p. in female nude athymic mice. After i.p. injection of these cells, animals develop metastatic spread similar to that of clinical ovarian cancer. Disease progression is characterized by the development of massive ascites, extensive invasive i.p. tumors, and pulmonary metastases. The malignant ascites cells are transplantable, manifest cytoplasmic androgen and estrogen receptors, and express the ovarian cancer associated antigen CA125 (116,000 units/ml of ascites supernatant). The cells also have the same chromosome markers which were present in the original cell line, NIH:OVCAR-3. Survival following i.p. passage of ascites is dependent on tumor cell inoculum ranging from a median survival of 39 days with 40 million cells to 84 days for 11.5 million transplanted cells. The characteristics of this unique in vivo model make it well suited for the evaluation of new drugs and novel experimental therapies in ovarian cancer. In addition, this in vivo model, together with ovarian cancer cell lines, may prove particularly useful for the study of pharmacological ways to specifically increase the cytotoxicity of anticancer agents in tumor cells while not increasing toxicity in normal tissues. The presence of hormone receptors should facilitate the experimental evaluation of hormonal therapy in ovarian cancer.

Potentiation of melphalan cytotoxicity in human ovarian cancer cell lines by glutathione depletion.

The effectiveness of alkylating agents in the treatment of ovarian cancer is limited by the frequent development of drug resistance. In order to examine the mechanisms of resistance and potential ways in which this resistance could be overcome, we have developed a human ovarian cancer cell line, 1847ME, resistant to the bifunctional amino acid nitrogen mustard, melphalan. A 4-fold higher concentration of melphalan was required to produce an equivalent reduction in tumor colony formation in 1847ME cells as compared to the parent melphalan-sensitive line A1847. The magnitude of resistance in 1847ME was similar to that observed in the cell lines NIH:OVCAR-2, NIH:OVCAR-3, and NIH:OVCAR-4 which were derived from ovarian cancer patients clinically resistant to alkylating agents. There was no detectable difference in melphalan uptake between A1847 and 1847ME. The cellular content of the inactive dihydroxy melphalan metabolite, however, was two times greater in 1847ME compared to A1847. Levels of the principal intracellular thiol, glutathione, were found to be 2-fold greater in 1847ME than in A1847, and to be similarly elevated in the OVCAR lines. Depletion of glutathione by incubation of the cells in cystine-free medium or in the presence of the specific inhibitor of glutathione synthesis, DL-buthionine-S,R-sulfoximine, was accompanied by a marked increase in melphalan cytotoxicity. Doses of DL-buthionine-S,R-sulfoximine which were only minimally cytotoxic were associated with complete reversal of the induced resistance to melphalan in 1847ME. Synergism between melphalan and DL-buthionine-S,R-sulfoximine was also demonstrated in the OVCAR cell lines derived from previously treated ovarian cancer patients. The reversal of induced resistance to melphalan by modulation of glutathione levels is of potential clinical relevance. In addition, these cell lines provide a useful model system in which to study further the mechanisms of alkylating agent resistance in human tumors.

Evaluation of platinum-DNA adduct levels relative to known prognostic variables in a cohort of ovarian cancer patients.

Single-agent chemotherapy with cisplatin or carboplatin can induce remissions in approximately 30% of previously treated patients with advanced stage ovarian cancer. Previous studies have shown that the extent of platinum-DNA adduct formation measured in WBC DNA of ovarian cancer patients treated with cisplatin or carboplatin is directly associated with disease response (Reed et al., Proc. Natl. Acad. Sci. USA, 84: 5024-5028, 1987). It has been unclear whether adduct level in WBC DNA is independent of known prognostic variables in this disease, or whether adduct level parallels a known prognostic variable that can be more easily monitored. In a cohort of 24 ovarian cancer patients treated with single-agent cisplatin or carboplatin, we retrospectively assessed the relationship between disease response, platinum-DNA adducts in WBC DNA, and each of eight prognostic variables by both univariate analysis and multivariate analysis. The prognostic variables evaluated included: response to previous treatment, Karnofsky status, total platinum dose prior to current therapy, stage of disease, age, bulk of disease at initiation of therapy, histological type, and histological grade. By univariate analysis, adduct level was strongly associated with disease response (two-sided P = 0.0058), with the next strongest associations with disease response being held by Karnofsky status (P = 0.125), stage of disease (P = 0.189), response to previous treatment (P = 0.352), total previous platinum dose (P = 0.358), and age (P = 0.374). No significant associations were found between adduct level and histological type or histological grade. Further, when patients were stratified by the number of cycles studied (one cycle, two cycles, or three cycles), higher levels of adduct were consistently seen in those patients responding to therapy. We conclude that, in this small cohort of refractory ovarian cancer patients treated with single-agent cisplatin or carboplatin, adduct level in WBC DNA appears to be more closely related to disease response than other previously identified prognostic variables.

Inhibition of human ovarian cancer colony formation by adriamycin and its major metabolites.

We have examined the in vitro sensitivity to Adriamycin of human ovarian cancer colonies cloned in soft agar. In the 26 patients tested, 3 different patterns of sensitivity to Adriamycin were observed: (a) in 75% of the previously untreated patients, there was greater than 70% reduction in colony-forming cells after exposure to Adriamycin (1.0 micrograms/ml), a level which approximates the peak plasma level after i.v. therapy; (b) in all the patients who had progressive disease while on a chemotherapy regimen without Adriamycin, a greater than 70% reduction in colony-forming cells was observed only at a concentration of 10 micrograms/ml, a level not achievable by i.v. administration; (c) in 80% of patients with progressive disease after treatment with Adriamycin as part of the primary chemotherapy regimen, a 70% reduction in tumor colony-forming cells could not be achieved even at 10 micrograms/ml. These in vitro results are in agreement with clinical observations regarding the effectiveness of Adriamycin in previously untreated patients (42% response rate) with ovarian cancer as well as its ineffectiveness (0 to 6% response rate) as a second-line therapy in relapsed patients. The results also have provided a rationale for an ongoing Phase I trial of i.p. Adriamycin in patients with ovarian cancer from Group b above since cytotoxic levels can be produced i.p. using large-volume dialysis via a Tenckhoff dialysis catheter. The relative cytotoxicity of Adriamycin to its two major metabolites, adriamycinol and adriamycin aglycone, was also determined in the clonogenic assay. Both derivatives produced suppression of ovarian cancer colony formation; however, Adriamycin was more cytotoxic that was either metabolite.