title: Differential cellular zinc levels in metastatic and primary nasopharyngeal carcinoma.
abstract: Zinc levels are known to be elevated in certain cancer tissues. In this study, zinc content in metastatic and primary nasopharyngeal carcinoma (NPC) cells were quantitated by X-ray microanalysis at the ultrastructural level. Zinc levels of cancer cells derived from the cervical lymph node of a patient with metastatic carcinoma and that from the nasopharynx biopsy of another NPC patient with no clinical evidence of secondary spread, were analyzed. X-ray microanalysis revealed significantly higher cellular zinc levels in metastatic NPC cells. Zinc is a known anti-apoptotic agent and tumor response to radiotherapy is linked with apoptosis or programmed cell death. Raised zinc levels observed here could provide the biological basis for the observation of a higher percentage of distant metastasis in cervical node positive NPC patients treated by radiotherapy (the mainstay of treatment for NPC) as compared to those without regional nodal disease.
authors.affiliation: NATL UNIV SINGAPORE,DEPT OTORHINOLARYNGOL,SINGAPORE 119260,SINGAPORE. SINGAPORE GEN HOSP,DEPT PATHOL,SINGAPORE 169608,SINGAPORE.
authors.forename: B
authors.initials: B
authors.lastname: Bay
authors.forename: Y
authors.initials: Y
authors.lastname: Chan
authors.forename: C
authors.initials: C
authors.lastname: Fong
authors.forename: H
authors.initials: H
authors.lastname: Leong