Tumors and Hormones

NOBLE, R.L.

doi:10.1016/b978-1-4832-2851-8.50013-7

Cited by 2 publications

(1 citation statement)

References 749 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…If the same experiments are performed in the pres ence of a carcinogen which, by inducing DNA-strand separation in some areas, pro vides more initiation sites, the alkaloids, at appropriate concentrations, may then pre vent cancer DNA replication at any moment. Steroids which are nonmutagenic substances induce the appearance of cancerous tissues in the mammary gland of mice [11,13], stimu late the in vitro multiplication of breast can cer cells [10,17], enhance breast cancer DNA in vitro synthesis and separate the chains of the DNAs isolated from breast cancer tissues [1], During this last process, alkaloids bind to newly liberated initiation sites and cause in hibition of DNA synthesis even if it has already started. However, it should be stressed that steroids at given concentrations may overcome the inhibition of cancer DNA synthesis caused by alkaloids.…”

Section: Conclusion and Discussionmentioning

confidence: 99%

Selective Inhibition of in vitro Synthesis of Cancer DNA by Alkaloids of β-Carboline Class

Beljanski¹,

Beljanski²

1982

Pathobiology

View full text Add to dashboard Cite

The high template in vitro activity of native DNA from cancerous mammalian and plant tissues, compared to DNA from healthy tissues, enabled us to select substances which selectively inhibit cancer DNA synthesis. Among them, alstonine, serpentine, semper-virine and flavopereirine, all alkaloids which belong to the β -carboline class, distinguish cancer DNA from healthy tissue DNA and inhibit DNA in vitro synthesis when native DNA from different cancerous tissues or cells is used as template. They have practically no effect on DNA from healthy tissues. The inhibitory effect of alkaloids is due to their capacity to form an ‘alkaloid-cancer DNA’ complex which has been characterized by use of the Sephadex column. Evidence is presented showing that these alkaloids inhibit the initiation of DNA synthesis but not chain elongation. The stimulating action caused by carcinogens during cancer DNA in vitro synthesis may be prevented and reversed by alkaloids. Furthermore, the stimulating action of steroids during in vitro synthesis of hormone target tissue DNA might be neutralized by alkaloids. However, at relatively high doses, steroids reversibly compete with alkaloids for binding sites on breast cancer DNA. This is not observed with DNA from nonhormone target tissues.

show abstract

Section: Conclusion and Discussionmentioning

confidence: 99%

Selective Inhibition of in vitro Synthesis of Cancer DNA by Alkaloids of β-Carboline Class

Beljanski¹,

Beljanski²

1982

Pathobiology

View full text Add to dashboard Cite

show abstract

The Nb rat prostatic adenocarcinoma's dose response to methotrexate and adriamycin

Drago

Palmer

1983

Journal of Surgical Oncology

View full text Add to dashboard Cite

The Noble rat prostatic adenocarcinoma, Nb-Pr-A.I.-II, an androgen-insensitive tumor, is the subject of this experiment. Dose responses were carried out with treatment of these tumors with three doses of adriamycin and two doses of methotrexate. Adriamycin treatment resulted in decreased tumor volume and decreased number of metastases in the higher dosage. Methotrexate also decreased metastasis and tumor volume. No animal treated with either of these agents in this protocol had the tumor undergo complete tumor regression, a criteria used in evaluation of chemotherapies with this animal model.

show abstract

Tumors and Hormones

Cited by 2 publications

References 749 publications

Selective Inhibition of in vitro Synthesis of Cancer DNA by Alkaloids of β-Carboline Class

Selective Inhibition of in vitro Synthesis of Cancer DNA by Alkaloids of β-Carboline Class

The Nb rat prostatic adenocarcinoma's dose response to methotrexate and adriamycin

Contact Info

Product

Resources

About