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W D DeWys

Publications and source records attributed to W D DeWys.

At least 55 records · Page 3Linked to original sources

Implications of the inhibition of animal tumors by dietary zinc deficiency.

Because zinc is an essential nutrient for tissue growth, cellular division, protein synthesis, and DNA and RNA replication, it also ought to play a critical role in the growth of tumors. To test this thesis, a series of experiments were performed to test the effect of zinc deficiency on the lethality of a variety of solid and ascites tumors in mice and rats. Specifically, the following models were tested: Walker 256 carcinosarcomas, solid and ascites forms in rats; three mouse leukemias (L5178yf, L1210, and P388) in CDF, male mice; and Lewis lung carcinoma in C57BI/6 male mice. Rats receiving a zinc-deficient diet showed marked reduction of tumor growth, both of solid or ascites models, and this was accompanied by striking increase in survival. Survival of mice with transplanted leukemia was also significantly prolonged by zinc deficiency. In addition, growth of the Lewis lung carcinoma was inhibited, but the survival through increased, was probably limited by the adverse effects of zinc deficiency. The results suggest that tumor inhibition is a general effect of zinc deficiency, irrespective of cell type, cell growth rate, species, or site of growth. There are numerous potential applications of zinc metabolism to the diagnosis, therapy, and understanding of cancer.

Animals↗

Effect of defibrination on tumor growth and response to chemotherapy.

Other investigators have demonstrated fibrin deposition in tumors. Experiments were therefore designed to test whether systemic defibrination would alter tumor growth or tumor response to chemotherapy with cyclophosphamide. Defibrination with Ancrod, a venom extract of Agkistrodon rhodostoma, did not significantly affect tumor sensitivity to chemotherapy. Similarly, defibrination plus fibrinolytic therapy with streptokinase did not affect responsiveness to cyclophosphamide. Long-term defibrination did not affect tumor growth. These results suggest three possible interpretations: (a) the coagulation system may not be important in tumor growth and response to chemotherapy; (b) adequate clearing of fibrin from the tumor was not accomplished in our experiments; or (c) other factors such as platelet deposition may be involved and platelet function was not inhibited by the therapies used in our experiments.

Ancrod↗

Abnormalities of taste sensation in cancer patients.

In fifty patients with cancer, subjective and objective correlates of anorexia of malignancy were studied. Decreased taste was reported by 25 patients, and an aversion for meat was reported by 16 patients. The decreased taste symptom correlated with an elevated taste threshold for sweet (sucrose), and the symptom of meat aversion correlated with a lowered taste threshold for bitter (urea). The likelihood of having a taste abnormality increased with increasing extent of disease, but not with histologic type of neoplasm. Patients with an abnormality of taste had an increased incidence of weight loss compared with patients with normal taste, even though many in the latter group had other causes of weight loss. These observations suggest that an abnormality of taste may be one determinant of the anorexia of malignancy. Better understanding of the anorexia in the cancer patient may contribute to the care of the patient.

Adult↗

Current concepts of chemotherapy combined with other modalities for head and neck cancer.

This paper presents an overview of studies of therapy of head and neck squamous cell carcinoma in which chemotherapy was combined with other modalities. The rationale for using chemotherapy with surgery is discussed, but ststematic studies of this combination of modalities have not been reported. Systemic chemotherapy plus radiation therapy has been studied using hydrozyurea, t-fluorouracil (5-FU), and methotrexate (MTX). Uncontrolled studies with hydroxyurea report favorable results, but a well-controlled study gave negative results. Controlled studies with 5-FU have given favorable results in certain tumor stages and sites of origin. MTX plus radiation in a small series produced slightly better survival than radiation alone. Intra-arterial chemotherapy plus radiation therapy has been the subject of exploratory studies but no firm conclusions can be drawn from these studies. Chemotherapy plus immunotherapy has been explored and merits further study. Based on the studies reported to date one can suggest the need for large-scale randomized control studies of long-term chemotherapy combined with other modalities.

Bleomycin↗