Activity of cytotoxic agents against clear cell carcinoma of the ovary which is intrinsically platinum-refractory

The aim of the present study was to evaluate cytotoxic agents active for clear cell carcinoma of the ovary (OCCA) which is intrinsically platinum-resistant. We first conducted in vitro chemosensitivity tests assessing antitumor activities of Various agents against OCCA using two cell lines (HAC-2 and KK) established from ascites of patients with pure OCCA. The most potent single agent was SN-38 (active substance of CPT-11 in vivo) in both cell lines. The second most potent agent was mitomycin-C (MMC) followed by doxorubicin (DOX) in HAC-2 and DOX followed by MMC in KK, respectively. In vivo chemosensitivity test of agents on HAC-2 transplanted into BALB/C nude mice demonstrated that MMC was most potent, followed by DOX and CPT-11. Moreover, a combination of CPT-11 and MMC exhibited the highest anti-tumor activity in this animal model. Cisplatin, etoposide, and paclitaxel were found to be ineffective in either the in vitro or in vivo experimental system. Clinical trial with a combination of MMC and CPT-11 are warranted in patients with OCCA.     

Induction of apoptosis in ovarian carcinoma cell line by glucocorticoids, and sex steroid hormones

We investigated the interactions in the KOC-2s human ovarian cancer cells on the effect of glucocorticoids, and sex steroid hormones in ovarian carcinomas. At 10(-8) M to 10(-5) M, dexamethasone (Dex) decreased the number of cells by 75-80% (p<0.001). At 10(-8) M and 10(-7) M, hydrocortisone (HC) decreased the number by 50% (p<0.01); at 10(-6) M and 10(-5) M, the decrease in number of cells was 65%. The E-2 decrease in number was not statistically significant. Progesterone (PG) showed at 10(-8) to 10(-6) M an increase in number of cells, however, at 10(-5) M it was decreased by 70% with a significant difference (p<0.001). Dex (10(-8)-10(-5) M), HC (10(-8)-10(-5) M) and PG (10(-5) M) produced internucleosomal cleavage of DNA into fragments with multiples of 180 to 200 bp. The TNF-alpha with addition of Dex (10(-8)-10(-5) M) and HC (10(-8)-10(-5) M) was increased after 24 h, 48 h (p<0.001); however, gradually decrease after 72 h. When PG (10(-8)-10(-5) M) was added, PG (10(-5) M) increased the secretion of TNF-alpha after 72 h. Our findings demonstrate that glucocorticoids, and PG directly induce apoptotic DNA fragmentation of KOC-2s cells. However, the secretion of TNF-alpha and expression of Fas antigen were totally different in these substances. These data provide a basis for future studies on the mechanisms of apoptotic effect of glucocorticoids, and PG and the therapeutic effects of these substances.     

p53 mutations of lung cancer are not significantly affected by CYP1A1 or GSTM1 polymorphisms

Cytochrome p4501A1 gene (CYP1A1) and glutathione S-transferase mu gene (GSTM1) are involved in the metabolic activation or detoxification of environmental carcinogens including benzo[a]pyrene in tobacco smoke. Individuals with both Val/Val and C type of CYP1A1 (CYP1A1; Val/Val and CYP1A1; C) or homozygous null (-/-) genotype of GSTM1 gene (GSTM1; -/-) show increased susceptibility to lung cancer. The incidence of p53 gene mutations are related to the smoking index of the lung cancer patients. Therefore we determined genotypes of these enzymes and screened p53 gene mutations in 123 non-small cell lung cancer (NSCLC) patients. p53 gene mutations were found in 35% (43/123) of the patients. The incidence of p53 gene mutation CYP1A1; Val/Val (60.0%), CYP1A1; C (50.0%) tended to be higher than those of CYPIAI; Ile/Ile and Ile/Val (40.4%) or CYP1A1; A and B (40.5%). We conclude that the incidence of the p53 mutations does not seem to be significantly affected by only CYP1A1 or GSTM1 polymorphisms in lung cancer patients.     

Studies of effects of anticancer agents in combination with/without hyperthermia on metastasized human bladder cancer cells in chick embryos using the polymerase chain reaction technique

Cultivated T24 cells derived from a human bladder cancer were inoculated into the chorioallantoic membrane vein of chick embryos. Hyperthermic treatment was performed following injection of anticancer agents 3 days after the inoculation of the T24 cells. DNA samples were obtained from the livers of the chick embryos, and the polymerase chain reaction technique was used to amplify a DNA fragment specific to the human -globin gene. The Southern hybridization method was used to evaluate the inhibitory effects of anticancer agents in combination with/without hyperthermia on T24 cells metastasized to the liver. The hyperthermia exerted an inhibitory effect on the growth of the T24 cells in the livers of the chick embryos, and this was dependent on the thermal dose. The antitumor effects of hyperthermia performed at 42.5° C for 20 min and at 43.0° C for 10 min were evidenced by 69.2% an 82.0% inhibition of the growth of the metastasized T24 cells, respectively, as compared with the growth of untreated T24 cell. Hyperthermia performed at 42.5° C for 10 min alone produced 26.7% tumor growth inhibition, and these conditions for hyperthermia were subsequently used as a criterion for evaluating the effects of its combination with various anticancer agents. Adriamycin (20 g/egg) alone, mitomycin C (10 g/egg) alone, carboplatin (10 g/egg) alone, and cisplatin (10 g/egg) alone produced 13.5%, 58.9%, 27.3%, and 29.1% tumor growth inhibition, respectively. Adriamycin and mitomycin C applied in combination with hyperthermia showed additive inhibitory effects on the growth of the metastasized T24 cells in this chick embryo model.     

The urinary excretion of pyridinium cross-links as markers of bone metastasis in breast cancer

The collagen cross-links, pyridinoline (Pyr) and deoxypyridinoline (D-Pyr) excreted in urine have recently been suggested as new markers of bone metastasis. In a pilot study we measured Pyr and D-Pyr in 61 patients with breast cancer, 16 with known bone metastasis and 45 with no recognized metastasis in bone. Twenty healthy female subjects were also measured as controls. The mean values (+/-SD) of Pyr and D-Pyr in the group with bone metastasis were significantly higher (Pyr: p<0.01, D-Pyr: p <0.05) than those in the group without bone metastasis and in the control group. The mean (+/-SD) values of postmenopausal women were significantly higher than those of premenopausal in the group without bone metastasis (p<0.05) and in the control group (p<0.01). Therefore, the effect of menopause should be taken into account in the diagnosis of bone metastasis by assays of Pyr and D-Pyr. Setting the cut-off values (mean + 2SD of the values of control) for pre and postmenopausal patients, the accuracy for Pyr was 71.4% in premenopausal and 75.8% in postmenopausal patients; and for D-Pyr it was 71.4% and 78.8% respectively. We consider that measurement of urinary collagen cross-links assays can contribute to the early detection of metastatic spread to bone in breast cancer.     

Cytotoxic impacts on the tumorigenesis and transplantability of ovarian teratoma in lt/sv mouse

The incidence and transplantability of ovarian teratoma in LT/Sv mice were examined following cisplatin treatment at the age of 16 days, and compared to those in the control group. Cisplatin had not affected the emergence of egg cleavage, which simultaneously appeared in the mouse ovaries in both groups. Although 7 teratomas, occasionally transplantable, developed in the control mice aged over 30 days, only 2 tumors occurred in cisplatin-treated mice at the age of 120 days and they were not transplantable. The results suggest that cisplatin might influence the tumorigenic process after egg cleavage, or transplantability of teratoma.     

A study on how a 6-month aerobic exercise program can modify coronary risk factors depending on their severity in middle-aged sedentary women

It is well known that physical exercise can reduce coronary risk factors. But how an aerobic exercise modifies coronary risk factors in relation to severity and physical fitness is still controversial. Fifty-four middle-aged women (mean age, 55 years) completed a 6-month on-site and home-based anaerobic threshold-level exercise program. The changes in coronary risk factor profiles were observed during the pre-intervention and intervention periods. Before the intervention (during control period), most coronary risk factors showed a rather unfavorable trend. After the program, their mean body weight decreased from 56.7 to 55.7 kg (p>0.05) and the proportion of body fat from 30.9 to 27.9% (p>0.05) without any reduction in lean body mass. Systolic blood pressure (SBP) decreased from 129.0 to 125.0 mm Hg (p>0.05) and diastolic blood pressure from 79.5 to 76.6 mm Hg (p>0.05). Fasting plasma glucose (FPG) declined from 109.6 to 103.4 mg/dl (p>0.05). Changes in SBP and FPG were most remarkable in their respective worst tertile. Serum lipids improved only modestly. Maximum oxygen uptake increased from 23.6 to 26.1 ml/kg/min (p>0.01). However, no significant correlations were found between changes in coronary risk factors and those in physical fitness. We conclude that the 6-month aerobic exercise program would modify women’s coronary risk factors depending on their initial values, probably independently of the changes in physical fitness.     

Signal separation of background EEG and spike by using morphological filter

A signal separation method for extracting background electroencephalogram (EEG) from EEG containing spikes was proposed. Morphological filters were designed for extracting spike waveforms, and then the background EEG was obtained by subtracting the detected spike waveforms from the EEG with spike. The proposed method was evaluated by using simulated EEG data, which consisted of a summation of EEG without spike and model waveform of typical spike. The background EEG separated by the method was processed by the automatic background EEG interpretation.     

Reduction of tumorigenicity by an interferon-γ-gene-transduced tumor on another syngeneic tumor in a murine model

To evaluate the effect of interferon-γ-genetransduced cells, DS mice were inoculated into their footpads with syngeneic mammary adenocarcinoma SC42 admixed with interferon-γ producing mammary adenocarcinoma SC115Kγ, which had been established by an interferon-γ-gene transduction in another syngeneic mammary adenocarcinoma SC115 using retroviral vectors. These mice rejected both tumor cells and developed resistance to subsequent challenges with either SC115 or SC42 cells inoculated into their opposite posterior footpads. These results thus indicate that systemic immunological memory to each of the independent tumor cell lines developed in these mice. Although the SC42 cells admixed with irradiated SC115Kγ cells were rejected by these mice, the SC42 cells admixed with irradiated SC115neoR, in which the neo-gene had been transduced, were observed to proliferate. Tumor rejection was reversed by an in vivo administration of anti-interferon-γ antibody, thus suggesting that locally produced interferon-γ plays an important role in tumor elimination and immunological memory induction. In conclusion, interferon-γ-gene-transduced tumor cells are therefore considered to have a therapeutic potential for other types of malignant tumor cell lines.     

Estimation of physiologic ability and surgical stress (E-PASS) as a new prediction scoring system for postoperative morbidity and mortality following elective gastrointestinal surgery

(Received for publication on Oct. 25, 1997; accepted on July 7, 1998)