Comparative EPR Study on the Scavenging Effect of Methotrexate with the Isomers of Its Photoswitchable Derivative.

The scavenging effect of the antimetabolite dihydrofolate reductase inhibitor methotrexate (MTX) and the isomers of its photoswitchable derivate, cis- and trans-phototrexate (PHX), have been compared by ESR spectroscopy, with the application of a cyclic hydroxylamine spin probe. The results showed the most pronounced scavenging effect in the presence of trans-phototrexate (trans-PHX). At a low concentration (100 µM) cis-PHX also showed a greater scavenging effect than the parent molecule MTX. Direct antioxidant properties of the investigated molecules were measured by ABTS scavenging assay, which showed no significant difference between trans-PHX and cis-PHX, but both of the isomers of PHX showed a higher antioxidant capacity than MTX. These findings imply that trans-PHX may have more pronounced anti-inflammatory and tissue-protective effects than MTX, despite the lack of its cytotoxic, antineoplastic effect.

Effect of methotrexate and its photodegradation products on the temperature induced denaturation of human serum albumin.

Effect of the photodegradation of chemotherapeutic agent methotrexate on the denaturation of human serum albumin has been studied by differential scanning calorimetry and fluorimetric measurements. Photoluminescence studies highlighted entropy driven binding of both methotrexate molecules and its degradation products to the albumin molecules. The calorimetric measurements evaluated by the Kissinger method show elevated activation energy in the presence of methotrexate. Similar but moderated enhancement of the activation energy was obtained in the presence of the photodegradation products of methotrexate. These results highlight stabilization of the human serum albumin by the methotrexate drug which finding may contribute to fine tuning of methotrexate applications in therapy.

Diagnostic relevance of urinary steroid profiles on ovarian granulosa cell tumors: two case reports.

BACKGROUND: Granulosa cell tumor of the ovary is the most frequent sex cord stromal tumor and represents 2 to 5% of all primary ovarian cancers. Ovarian granulosa cell tumor is a malignant tumor with slow progression and in some cases this tumor is hormonally active. The recurrence of granulosa cell tumor often happens after 5 years. CASE PRESENTATION: We describe two cases of postmenopausal women with adult-type granulosa cell tumors of the ovary. Patient 1 is a 49-year-old European woman with a recurrent tumor; patient 2 is a 55-year-old European woman without recurrence of tumor. Urinary steroid profiles of patient 1 were monitored during a 5-year period starting from before an operation (13 samples). In patient 2, the urinary steroid profiles were monitored during a 3-year period starting from after an operation (six samples). The 24-hour urinary samples were examined and the urinary concentration of 20 androgen, progesterone, and corticoid metabolites was quantitatively determined by gas chromatography-mass spectrometry with selected ion-monitoring mode. CONCLUSIONS: Based on these cases a correlation could be observed between increased levels of the urinary steroids and the recurrence of ovarian granulosa cell tumor; therefore, we concluded that a urinary steroid profile could be a more effective method to follow-up such patients compared to the traditional serum hormones determinations supplemented with conventional tumor markers.