Growth suppression of four cancer cells by hyperbaric nitrous oxide and methotrexate
نویسندگان
چکیده
BACKGROUND Nitrous oxide concentration is easily controlled by respiratory ventilation. It suppresses bone marrow via the inhibition of thymidylate synthesis. The aim of this work was to determine the optimal pressure and exposure duration of nitrous oxide, as well as methotrexate concentration that maximizes the suppression of 4 cancer cells: CCRF-CEM, K562, A549 and MDA-MB-231. METHODS Each cancer cell was cultured in a hyperbaric chamber at 1, 2 and 3 atmosphere of 74% nitrous oxide for 24, 48, and 72 hours at 0, 0.3, 0.7, 1, 2, 5 and 10 microM methotrexate (MTX), respectively. The results were expressed in the ratio of the number of cancer cells cultured under specific conditions (S cells) to that under normal conditions (N cells). RESULTS The S/N ratio of CCRF-CEM cells was 87.4% in 24-hour culture, 95.0% in 48-hour culture and 115.9% in 72-hour culture (P < 0.05). The S/N ratio of K562 cells was 103.6% at 1 atm, 102.4% at 2 atm and 115.6% at 3 atm (P < 0.05). The S/N ratio of A549 cells was 94.3% at 1 atm, 94.1% at 2 atm, 99.3% at 3 atm, 96.2% in 24-hour culture, 99.2% in 48-hour culture and 99.3% in 72-hour culture (P > 0.05). However, the S/N ratio of MDA-MB 231 cells was 66.9% in 24-hour culture, 83.1% in 48 hour culture and 87.8% in 72-hour culture (P < 0.05). CONCLUSIONS Only the growth of the MDA-MB-231 cells was significantly reduced after a longer exposure time to nitrous oxide, but those of the other cells were not.
منابع مشابه
Erratum: Growth suppression of four cancer cells by hyperbaric nitrous oxide and methotrexate (Korean J Anesthesiol 2010; 58(1): 61-69)
متن کامل
Effect of nitrous oxide on human bone marrow cells and its synergistic effect with methionine and methotrexate on functional folate deficiency.
5-Methyltetrahydrofolate homocysteine methyltransferase activity in human bone marrow cells obtained from patients undergoing surgical operation became low after about 4 hr of nitrous oxide (N2O) anesthesia. The deoxyuridine suppression test performed on these bone marrow cells also became abnormal after about 6 hr of N2O anesthesia. The incorporation of [3H]thymidine into DNA in the bone marro...
متن کاملMethotrexate rescue by 5-methyltetrahydrofolate or 5-formyltetrahydrofolate in lymphoblast cell lines.
The rescue of lymphocytes from methotrexate (MTX) growth inhibition by 5-methyltetrahydrofolate (5-methyl-THF) and 5-formyltetrahydrofolate (5-formyl-THF) has been studied. Rescue by 5-methyl-THF is selective for cells with high levels of homocysteine:5-methyl-THF methyl-transferase (methyltransferase). At MTX concentrations which inhibited growth greater than or equal to 85% in both leukemic T...
متن کاملEffects of nitrous oxide on human cell lines.
Hematopoietic and nonhematopoietic cell lines cultured in media containing either 5-methyltetrahydrofolate or 5-formyltetrahydrofolate grow well to the same extent. However, when these same cell lines are grown in the presence of nitrous oxide, selective growth inhibition can be shown for hematopoietic cells cultured in 5-methyltetrahydrofolate-containing media. These cells also demonstrated a ...
متن کاملSuppressive effect of nitrous oxide on motor evoked potentials can be reversed by train stimulation in rabbits under ketamine/fentanyl anaesthesia, but not with additional propofol.
The effect of nitrous oxide on myogenic motor evoked potentials (MEPs) after multipulse stimulation is controversial. We investigated the effects of propofol in this paradigm. MEPs were elicited electrically by a single pulse and by trains of three and five pulses in rabbits anaesthetized with ketamine and fentanyl. Nitrous oxide 30-70% was given and MEPs were recorded. After washout of nitrous...
متن کامل