Estradiol and progesterone receptors in malignant gastrointestinal tumors.

Estradiol and progesterone receptors were assayed in tumors from 79 patients with primary colorectal and 56 patients with stomach adenocarcinomas. Eighteen of 79 colorectal cancers contained estradiol receptor, while 34 specimens were positive for progesterone receptor. In stomach cancer, the positive samples were 8 for estradiol and 14 for progesterone receptors. In both types of tumors, the Kd was in the range of 10(-10) M for estradiol and 10(-9) M for progesterone receptor, respectively. In colorectal adenocarcinomas, the presence of progesterone receptor seems to be partially correlated to the presence of estradiol receptor while, in stomach tumors, this correlation is lost. The positivity of at least one receptor in colorectal cancers is higher in the female sex. The contrary occurs for stomach cancer. Sucrose gradient centrifugation showed that cytoplasmic estradiol receptor of stomach cancer sedimented at 8S or 4 to 5S at low ionic strength. The isoelectric point of stomach cancer estradiol receptor is 6.5.

Estrogen and progesterone binding proteins in human colorectal cancer. A preliminary characterization of estradiol receptor.

Estradiol receptor (ER) and progesterone receptor (PgR) were assayed in tumors from 20 patients with primary colorectal cancer. Ten of 20 tumors contained high affinity sites for 17 beta-estradiol and progesterone. The highest concentration of ER was 56 fmol/mg of protein. The ER dissociation constant ranged from 1.6 X 10(-10) M (mean 4.6 +/- 2.6). The highest concentration of PgR was 42 fmol/mg of protein. The PgR dissociation constant ranged from 3 X 10(-9) to 9 X 10(-9) M (mean 5.65 +/- 2.1). Four out of 20 specimens analyzed were from male patients and all resulted negative for both receptors. Sixty per cent of ER positive tumors were also PgR positive, whereas only 20% of ER negative were PgR positive. Sucrose gradient centrifugation showed that cytoplasmic ER of colorectal cancer sedimented at 3 S in the absence of protease inhibitors and at 4.5 S in the presence of 1 mM phenylmethylsulphonyl fluoride (PMSF) both in low and in high ionic strength. When chromatographed on Sephadex G-200 almost all ER was quantitatively recovered in the included fractions. Molecular weights of ER eluted from Sephadex G-200 ranged from 90,000 to 50,000 daltons. Elution profile and molecular weight heterogeneity suggest that, in spite of the presence of PMSF, there is a limited proteolysis of ER. Partially purified colorectal cancer ER did not bind to sepharose-heparin. The isoelectric point of ER was 6.4-6.5.

Interference of MHV3 virus on ascites tumor growth.

In this experimental study the Authors have evaluated the interference of MHV3 hepatitis virus on Ascites Tumor's growth, using 4 groups of mice, the first one considered as control, the others inoculated with the virus 48 hours before, at the same time and 48 hours after tumor's inoculation. In each group labeling index, mitotic index and ascites volume were assessed a week after tumor's inoculation. The results seem to reveal an inhibition of tumor's growth in the second group. For this reason on the base of these encouraging observation, the Authors will continue researches to further confirm these preliminary results.

[Association of gastric cancer and hepatitis. A theory to be verified]. / L'associazione "cancro gastrico-epatite". Un'ipotesi da verificare.

The protective implications of transfusion hepatitis with respect to cancer are examined. It was observed that three patients suffering from advanced stomach cancer (IIIrd and IVth stage TNM), submitted to palliative surgery, contracted a probably transfusional hepatitis in the postoperative period and thereafter showed remission of the basic disease. Mechanisms of aspecific immunitary activation and/or a direct cytotoxic action on the part of the virus are postulated.