Induction of apoptosis and down-regulation of bcl-6 in mutu I cells treated with ethanolic extracts of the Chinese herbal supplement PC-SPES.

PC-SPES, an HPLC-standardized 8-herb dietary supplement prepared by proprietary extraction/mixing technologies, appears to have a number of health benefits when given to cancer patients. These include reduction of serum PSA (prostate specific antigen) in individuals diagnosed with advanced prostate carcinoma, and overall improvement of morbidity and immune status in terminal cancer cases. Since the expression of bcl-6 in T and B lymphocytes has been reported to be significantly down regulated by mitogens, we reason that the immune boosting effects of PC-SPES could involve the modulation of bcl-6 expression. Such a hypothesis was tested in the bcl-6 abundant Mutu I cells. Specifically, we investigated the effects of PC-SPES in regulating cell growth, induction of apoptosis, effecting changes in the retinoblastoma gene RB and the modulation of expression of the bcl-6. Herein we report that proliferation of Mutu I cells was inhibited by a 3-7 day incubation with ethanolic extracts of PC-SPES, with concurrent induction of apoptosis. In addition, a dose-dependent reduction of bcl-6 was observed, with no concomitant change in either the phosphorylated or the unphosphorylated forms of RB. These data raise the possibility that PC-SPES may enhance immune functions in vivo by down-regulating bcl-6 expression. Alternatively, decrease in bcl-6 could serve as a biomarker for testing the efficaciousness of PC-SPES in vivo.

In vivo determinations of labelling index of metastatic colorectal carcinoma and normal colonic mucosa using intravenous infusions of bromodeoxyuridine.

In vivo determination of the labelling index of metastatic colon carcinoma was performed in 14 patients following intravenous infusion of bromodeoxyuridine (BrdU), at doses of 100 and 50 mg/M2. No toxicity was seen. Labelled cells were detected by an immunohistochemical technique using a monoclonal antibody to BrdU. Labelling was uniform and highly specific with good preservation of morphology. Labelling index values ranged from 15.0-40.6% for metastatic lesions and 3.6%-20% for normal colonic mucosa, with mean values of 24% and 11%, respectively. This represents a useful new method for in vivo labelling index determination in solid tumors.

Eastern Cooperative Oncology Group: a comparison of adjuvant doxorubicin and observation for patients with localized soft tissue sarcoma.

Forty-seven patients with stage I, II, or III soft tissue sarcoma were entered into a prospective randomized Eastern Cooperative Oncology Group (ECOG) adjuvant protocol. Eligibility included conservative or radical primary treatment for local cure. Patients were then randomized to control or Adriamycin (Adria Laboratories, Columbus, OH). Adriamycin was administered at 70 mg/m2 (slow push, every 3 weeks for seven courses for a maximum of 550 mg/m2). To date, 32 patients, 17 males and 15 females, with an age range of 17 to 75 years (median, 44 years) have been followed sufficiently long to be included in this analysis. Nine patients have died. The median follow-up of the remaining 23 patients is 30 months (range, 2 to 50 months). Survival was not significantly different between Adriamycin or control. However, the disease-free interval was slightly different in favor of observation. This preliminary report does not support the hypothesis that Adriamycin is an effective adjuvant therapy for soft tissue sarcoma. Due to the small numbers, these results must be interpreted in relation to our ability to detect a difference, if in fact one existed. These preliminary data suggest that adjuvant Adriamycin not be used outside the confines of a clinical trial such as the current intergroup adjuvant sarcoma study.

Analysis of cell surface light chain immunoglobulin expression by flow cytometry in normal controls: a new mathematical approach.

It has been observed in flow cytometric studies that in normal individuals there are proportionally more kappa+ than lambda+ bearing light chain B-cells. Overt predominance of one type of light chain bearing cell over the other is a characteristic of B-cell neoplasias, a phenomenon called clonal excess (CE). A mathematical model using the Weibull distribution is proposed for studying such an excess. The new approach is desirable for two reasons: First, it is parametric and hence offers a more sensitive and versatile analysis than its nonparametric counterparts. Second, it utilizes only the relevant information from the upper tails of the distributions of the fluorescence intensity of the kappa+ and lambda+ cells. Two measures of CE based on the Weibull model are proposed, and a normal range of variability was determined for each measure using a random sample of 48 normal controls. Such normal ranges are particularly useful in detecting cancer patients with minimal B-cell neoplasias. A comparative study of the new measures, Ault's maximum difference measure, and a measure based on Ligler's method showed that the parametric approach provides much more sensitivity than both the nonparametric ones.

Induction of colon mucosal beta-glucuronidase production as a mechanism for 1,2-dimethylhydrazine colon carcinogenesis.

Although early studies in germ-free rats showed almost complete dependence on dimethylhydrazine (DMH) colon carcinogenesis upon the presence of colon bacteria, no adequate explanation was given for the 20% tumor incidence observed in germ-free animals. Bacterial activation of liver microsomal products releasing active proximate carcinogens has been the accepted reason for the exquisite specificity DMH has for the colon. Recent work, including the present study, show the colon mucosa is capable of metabolizing carcinogens and activating conjugating forms metabolized in the liver independent of the intestinal microflora. Mucosal beta-glucuronidase production was assayed in coded, scraped mucosa samples from the duodenum/jejunum, ileum, right colon, and left colon of normal and DMH-treated rats. Normal mucosal beta-glucuronidase production was highest in the left colon followed by the right colon, duodenum, and ileum, respectively. Enzyme production in the left colon was significantly increased 24 hours after injection of 25 mg/kg body weight DMH. No elevation was seen in other mucosal samples. Metabolism of DMH to oxidated forms conjugated to glucuronic acid is well established. Thus, this study offers a possible role for carcinogen, induction of a metabolic enzyme in its target tissue.

Cells from normal and malignant human colon mucosa differentially inhibit embryonic cell aggregation.

A model system for studying some aspects of the interaction of cancer cells in tumors and their surrounding nonmalignant tissue is the co-culture of cancer cells and embryonic chick neural retinal cells in gyratory shakers. Neural retina cell aggregation, under these conditions, has been shown to be differentially inhibited by small numbers of cultured mouse and human cancer cells. We extend here these observations to co-cultures of retinal cells with small numbers (60:1 ratio) of human cells isolated from normal colon mucosa or colonic adenocarcinoma tissue. The cells from the malignant tissue samples inhibited aggregation to a significantly greater extent than the cells from normal mucosa, even when both were from the same individual. Cells derived from nonmalignant tumors were more inhibitory than those from normal individuals, which is consistent with described differences in this 'transitional' region. Thus, the aggregation inhibition assay appears applicable to freshly isolated human tissues.

Photoradiation therapy for the treatment of malignant tumors.

Administration of hematoporphyrin derivative i.v. followed by local exposure to red light has resulted in complete or partial response in 111 of 113 cutaneous or s.c. malignant lesions. Tumors treated have included carcinomas of the breast, colon, prostate, squamous cell, basal cell, and endometrium; malignant melanoma; mycosis fungoides; chondrosarcoma; and angiosarcoma. No type has been found to be unresponsive. In several cases complete clearing of chest wall metastatis has been achieved in treated areas. Deep-seated and pigmented tumors required a higher dose of drug for effective treatment than did the more superficial and nonpigmented lesions. A high therapeutic ratio between tumor and skin response has been obtained by allowing at least 3 days between drug injection and exposure to the therapeutic light for 2,5-mg/kg doses and at least a 4-day interval for 5.0-mg/kg doses.

Adenosine deaminase levels in construction workers with asbestos contact dermatitis.

Adenosine deaminase (ADA) activity was measured in the lymphocytes, red blood cells and plasma of twelve construction workers with cutaneous hypersensitivity reactions to asbestos. Lymphocyte ADA activity was significantly greater in exposed individuals than a control population (p less than 0.0001), whereas erythrocyte and plasma enzyme activity did not differ from control determinations. ADA catalyzes the conversion of adenosine to inosine. Since increased adenosine concentrations in tissue culture inhibit the growth of lymphoblastic cell lines, it has been postulated that decreased ADA activity can result in suppression of the immune response by the inhibition of cell division. Our results indicate that the converse also applies, such that an increase in lymphocyte ADA activity may reflect an increased immune response.

Renin-angiotensin-aldosterone system in long-term renal transplant patients.

Seventeen anephric patients who constituted the subjects of this study received renal allografts between the years 1969 to 1973. The renin-angiotensin-aldosterone mechanism was evaluated in relation to either a normotensive or hypertensive clinical state in these subjects. Group I (Controls) were normotensive and on a normal diet; Group II were normotensive, on sodium restriction for five days, followed by saline infusion on the seventh day; and Group III were hypertensive, on similar sodium restriction for five days, followed by saline infusion on the seventh day. Glomerular filtration rates and levels of plasma renin and aldosterone, and the secretion rate of the latter were obtained on appropriate days. These studies confirm that an intact renin-angiotensin-aldosterone relationship exists in human renal transplant patients. The presence of high aldosterone secretion rate without hypertension is a new but unexplained finding. The lack of correlation of high aldosterone secretion rates in our normotensive and hypertensive patients suggests that aldosterone does not play a detectable or significant role in the pathogenesis of chronic or sustained transplant hypertension.