Induction of progesterone receptor with tamoxifen in human breast cancer with special reference to its behavior over time

The behavior of progesterone receptor (PR) values over time in human breast cancer during tamoxifen treatment was studied. Of 97 patients with operable breast cancer, 24 were preoperatively treated with tamoxifen (20 mg twice daily) for 3 days (TAM 3-day), 22 were treated for 7 days (TAM 7-day), 21 for 14 days (TAM 14-day), and 30 received no treatment (control group). Surgically removed breast tumors were assayed for the progesterone receptor by the dextran-coated charcoal method. The PR values (fmol/mg DNA) (mean +/- standard error [SE]) of PR-positive tumors in the control, TAM-3, TAM-7, and TAM-14 day groups were 571 +/- 176, 1699 +/- 408 (P less than 0.01), 1675 +/- 463 (P less than 0.05), and 686 +/- 191, respectively. There was a 4.6-fold increase in the mean PR value in postmenopausal patients and a two-fold increase in premenopausal patients after TAM treatment for 3 and 7 days. We concluded that PR induction provoked by TAM reached a peak on day 3, continuing at this level until day 7. A longer treatment (14 days) with TAM appears to abolish the PR inducing activity, probably because of, first, estrogenic and, later, the antiestrogenic effects of TAM.     

A noxious stimulus induces the preprotachykinin-A gene expression in the rat dorsal root ganglion: a quantitative study using in situ hybridization histochemistry

Using in situ hybridization histochemistry, we examined the biosynthesis of the preprotachykinin-A (PPTA) mRNAs, which code for substance P (SP) and also a related peptide, substance K (SK), in the rat dorsal root ganglion (DRG). The animals were injected with a small amount of formalin in the right hindpaw for nociceptive chemical stimulation. Analysis of hybridization signals in the emulsion autoradiography showed that the lumbar-5 DRG neurons expressing PPTA mRNAs were significantly increased in number and signal intensity on the formalin-injected side. Such elevation of the PPTA mRNA expression in the DRG was observed as early as 3 h after formalin injection. These results show that the expression of the PPTA gene is activated by chemogenic noxious stimuli.     

A tetrodotoxin-like substance as a minor toxin in the xanthid crab Atergatis floridus

Toxins were extracted from the xanthid crab Atergatis floridus inhabiting Ishigaki Island, Okinawa, and subjected to several types of chromatography, resulting in separation into gonyautoxin and saxitoxin fractions. Thin-layer chromatographic and electrophoretic analyses showed that the gonyautoxin fraction was composed of gonyautoxins 1-4, along with some unknown compounds. Gas chromatography-mass spectrometry demonstrated that the gonyautoxin fraction gave rise to the C9-base when alkali-hydrolyzed, indicating that this fraction contained a tetrodotoxin-like compound possessing the quinazoline skeleton specific to tetrodotoxin. The saxitoxin fraction consisted of neosaxitoxin, saxitoxin and two unknown compounds.     

Immunohistochemical distinction of malignant mesothelioma from pulmonary adenocarcinoma with anti-surfactant apoprotein, anti-Lewisa, and anti-Tn antibodies

Nine cases of malignant mesothelioma of pure epithelial and biphasic types (five pleural, three peritoneal, and one pericardial mesotheliomas), seven cases of benign adenomatoid tumor of the uterus, and 21 cases of peripheral pulmonary adenocarcinoma of non-mucus-producing type were examined immunohistochemically for expression of keratin, vimentin, carcinoembryonic antigen (CEA), surfactant apoprotein, Lewis blood group antigens, and Tn antigen. The majority (78%) of the malignant mesotheliomas expressed keratin, but CEA and surfactant apoprotein were not detected in any mesotheliomas. On the other hand, pulmonary adenocarcinomas expressed not only keratin (100%), but also CEA (62%) and surfactant apoprotein (62%). The expression of Lewisa blood group antigen and Tn antigen was detected in 76% and 62% of the pulmonary adenocarcinomas, respectively, but only one mesothelioma was stained for Lewisa antigen. This study reveals that the majority of malignant mesotheliomas can be distinguished from pulmonary adenocarcinomas by immunohistochemcial staining for CEA, surfactant apoprotein, Lewisa antigen, and Tn antigen. Immunohistochemically, adenomatoid tumors behaved similarly to malignant mesotheliomas.