Splenic melanosis during normal murine C57BL/6 hair cycle and after chemotherapy

Cancer chemotherapy is associated with serious side effects, including temporary hair loss and impairment of pigmentation. We suspect that ectopic melanin deposition occurring due to chemotherapy may add to these effects worsening the already unpleasant symptoms. We associated the ectopic occurrence of follicular melanin after chemotherapy with splenic melanosis - an interesting example of extradermal melanin localization - and we expected an increase in splenic melanin deposition after chemotherapy. Using the C57BL/6 murine model of synchronized hair cycle induced by depilation, we visualized splenic melanin by means of several histological and histochemical protocols of staining: hematoxylin and eosin, May-Grünwald-Giemsa and Fontana-Masson. Unexpectedly, the splenic deposition of melanin decreased due to application of cyclophosphamide (i.p. 120 mg/ kg body weight on day 9 post depilation). The drop was abrupt and lasted for at least 5 days (day 13-18 post depilation), as compared with normal hair cycle. Moreover, in mice with normal, depilation-induced hair cycle we observed a similar drop shortly before entering catagen (day 15 post depilation), followed by a slow and partial increase in splenic melanization up to day 27 post depilation in both groups. We conclude that cyclophosphamide negatively affects splenic melanization and/or extradermal transfer of ectopic melanin from the dystrophic hair follicles, but the most powerful down-regulator of splenic melanosis is normal and dystrophic catagen - the phase of hair follicle involution and re-modelling

Pulmonary metastases of the A549-derived lung adenocarcinoma tumors growing in nude mice. A multiple case study

Lung adenocarcinoma is a leading human malignancy with fatal prognosis. Ninety percent of the deaths, however, are caused by metastases. The model of subcutaneous tumor xenograft in nude mice was adopted to study the growth of control and photodynamically treated tumors derived from the human A549 lung adenocarcinoma cell line. As a side-result of the primary studies, observations on the metastasis of these tumors to the murine lungs were collected, and reported in the present paper. The metastasizing primary tumors were drained by a prominent number of lymphatic vessels. The metastatic tissue revealed the morphology of well-differentiated or trans-differentiated adenocarcinoma. Further histological and histochemical analyses demonstrated the presence of golden-brown granules in the metastatic tissue, similar to these found in the tumor tissue. In contrast to the primary tumors, the electron paramagnetic resonance spectroscopy revealed no nitric oxide - hemoglobin complexes (a source of intense paramagnetic signals), in the metastases. No metastases were found in other murine organs; however, white infarctions were identified in a single liver. Taken together, the A549-derived tumors growing subcutaneously in nude mice can metastasize and grow on site in the pulmonary tissue. Thus, they can represent an alternative for the model of induced metastatic nodule formation, following intravenous administration of the cancerous cells

Dermatological applications of EPR : skin-deep or in-depth?

The skin is often referred to as the biggest uniform human body organ, and also as the "brain outside", exposed not only, like the lung epithelium, to the atmospheric air but to other constituents of the open environment including changeable temperature and solar irradiation. The importance of what happens in the skin is therefore not to be overestimated for general condition of the whole organism. Techniques of electron paramagnetic resonance (EPR; called also electron spin resonance, ESR) spectroscopy and imaging belong to the important experimental and diagnostic approaches in dermatology, but the size and shape of skin often make technical problems. The present chapter will cover the basic and clinical applications of EPR to study the skin (including skin tumors) and hair. As the numerous available review papers usually describe the specificity of the EPR-related methods for dermatologists, we decided to cover also some basic aspects of dermatology, to make the chapter more useful also to the specialists in EPR theory and instrumentation. A particular emphasis will be put on the most recent discoveries and innovations, to show that the apparently purely dermatological aspects of such investigations reveal also deeper, systemic implications