A Potential Concept In The Management of Tumors With Modulation of Prostaglandin, Nitric Oxide and Antioxidants

Noori S Al-Waili

doi:10.1100/tsw.2007.89

Abstract

Prostaglandins (PGs), nitric oxide (NO), free radicals and chronic inflammation play a major role in tumorogenesis. We have found in vivo that PGs suppress antibody production; reduce serum iron, and modulate bone marrow function. Tumors are associated with immunosuppression and anemia. We have hypothesized that the over-production of PGs is responsible for immunosuppression and anemia in conditions associated with increased production of PG such as tumor, and that PG inhibitors might help reversing immunosuppression and anemia, and play a role in eradication and prevention of tumors. This is supported by reports that demonstrate the immunosuppressive effects of PGs in tumors. PG inhibitors have also been shown to be crucial in the prevention of tumors such as esophageal and colon cancers. Others and we have found that high NO production was encountered in patients with cancer while antioxidants are decreased. Evidence supports the efficacy of PG inhibition in malignancies, and the concept of PG inhibition, NO modulation, anti-oxidants, immunotherapy with antibody or immune cells, and anti-inflammatory agents when used in the prevention and management of malignancies are discussed.

Highlights

In-vitro studies have shown that the addition of malignant cells synthesizing large amounts of PGs to spleen cells stimulated with sheep red blood cell (RBC) caused a marked suppression of antibody production in the sheep RBC
We studied the effects of PGA1 on antibody production against thymus-dependent antigen (Ag) (Sheep RBC) and thymus-independent Ag (E. coli) in rabbits
Evidence from clinical and preclinical studies indicates that PGs participates in carcinogenesis, inflammation, immune response suppression, apoptosis inhibition, angiogenesis, and tumor cell invasion and metastasis[29]

Summary

INTRODUCTION

In-vitro studies have shown that the addition of malignant cells synthesizing large amounts of PGs to spleen cells stimulated with sheep red blood cell (RBC) caused a marked suppression of antibody production in the sheep RBC. Evidence from clinical and preclinical studies indicates that PGs participates in carcinogenesis, inflammation, immune response suppression, apoptosis inhibition, angiogenesis, and tumor cell invasion and metastasis[29]. Recent review shows that studies indicate that COX-2 produced in breast cancer cells may be vital to the development of osteolytic bone metastases in patients with breast cancer, and that COX-2 inhibitors may be useful in halting this process[43]. Other review discussed impact of overexpression of COX-2 in tumors leading to an increase in PG levels, which affect angiogenesis, inhibition of apoptosis, stimulation of cell growth as well as the invasiveness and metastatic potential of malignant cells[44]

Prostaglandin inhibitors in cancer and Immunity

Prostaglandin and Prostaglandin Inhibition in Anemia

Cancer and Inflammation

POTENTIAL APPROACH FOR CANCER ETIOLOGY AND THERAPY