J Korean Surg Soc.  2000 Dec;59(6):751-758.

Induction of Metallothionein and Manganese-Containing Superoxide Dismutase by Paraquat in Peripheral White Blood Cells of Patients with Gastric Cancer

• Moon SP
• Choi CH
• Cha YJ
• Chang JH
• Kim CY
• Min YD

Abstract

PURPOSE: It is known that deficiency of metallothionein (MT) and manganese-containing superoxide dismutase (Mn-SOD), scavengers of reactive oxygen species, results in aging and carcinogenesis by inducing DNA damage. Paraquat can produce reactive oxygen species and induce antioxidants in human. In this study, an attempt was made to verify the relation between gastric carcinogensis and the induction rates of these antioxidants. METHODS: Peripheral blood of 24 randomly selected patients with gastric cancer, who were treated at Chosun University Hospital between Febuuary 1999 and December 1999, was examined. 3 male and 3 female patients in each decade from 40 to 70 years were selected. Twenty-four (24) volunteers with no laboratory, chemical, radiologic and endoscopic abnormalities during the same period were used for the normal control group. White blood cells were isolated from peripheral blood and incubated in culture media, including paraquat, for 18 hours at 37oC. MT and Mn-SOD mRNA expressions were examined using the reverse transcription-polymerase chain reaction (RT-PCR) method.
RESULTS
The induction rates of MT and Mn-SOD mRNA in the cancer group due to paraquat were lower than those in the control group. Also, the rates decreased in both groups with age. CONCLUSION: The inducibilities of MT and Mn-SOD mRNA by paraquat may play a role in the carcinogenesis of gastric cancer and in the aging process. Based on this result, patients with a high risk of gastric cancer should be screened actively for early detection.

Keyword

Gastric cancer; Metallothionein; Mn-SOD; Paraquat

MeSH Terms

Aging
Antioxidants
Carcinogenesis
Culture Media
DNA Damage
Female
Humans
Leukocytes*
Male
Metallothionein*
Paraquat*
Reactive Oxygen Species
RNA, Messenger
Stomach Neoplasms*
Superoxide Dismutase*
Superoxides*
Volunteers
Antioxidants
Culture Media
Metallothionein
Paraquat
RNA, Messenger
Reactive Oxygen Species
Superoxide Dismutase
Superoxides