Frequent cyclin D1 expression in chromate-induced lung cancers.
Ex-chromate workers are frequently afflicted with lung cancers, especially central-type squamous cell carcinomas (SCCs) of the lung. However, little is known about the molecular and cellular biologic characteristics of chromate-induced lung cancers. We investigated expression of cyclin D1, bcl-2, and p53 proteins in chromate-induced lung cancers by immunohistochemistry, compared with those in lung cancers from nonexposed individuals and those in individuals with pneumoconiosis. Of 19 chromate-induced lung cancers, 16 tumors were SCCs, including 11 central and 5 peripheral types. Eleven (69%) of 16 chromate SCCs showed cyclin D1 expression. In contrast, cyclin D1 expression was observed in only 3 (12%) of 26 SCCs from nonexposed individuals and 6 (16%) of 37 SCCs that developed in patients with pneumoconiosis, respectively. The frequency of cyclin D1 expression proved to be significantly higher in chromate-induced SCCs than in SCCs from nonexposed individuals and from those with pneumoconiosis (P < .001). When comparisons were extended to all histologic types of lung cancer, cyclin D1 expression was observed significantly more often in chromate-induced lung cancers than in lung cancers from nonexposed subjects and those from patients with pneumoconiosis (11 [58%] of 19 v 5 [10%] of 52, P < .001, and 7 [11%] of 63, P < .001, respectively). Frequencies of bcl-2 and p53 expression were not significantly different among lung cancers from ex-chromate workers, nonexposed individuals and those with pneumoconiosis. The current study suggests that cyclin D1 expression may be involved in the development of chromate-induced lung cancers, although its underlying mechanism remains to be determined.
Katabami
M
M
Iwamizawa Rosai Hospital, Japan.
Dosaka-Akita
H
H
Mishina
T
T
Honma
K
K
Kimura
K
K
Uchida
Y
Y
Morikawa
K
K
Mikami
H
H
Fukuda
S
S
Inuyama
Y
Y
Ohsaki
Y
Y
Kawakami
Y
Y
D000230:Adenocarcinoma / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D018287:Carcinoma, Large Cell / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D018288:Carcinoma, Small Cell / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D002840:Chromates / Q000009:adverse effects*; D019938:Cyclin D1 / Q000096:biosynthesis*; D006258:Head and Neck Neoplasms / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D016273:Occupational Exposure / Q000009:adverse effects*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis; D012907:Smoking / Q000009:adverse effects; D016159:Tumor Suppressor Protein p53 / Q000032:analysis
D002840:Chromates; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D019938:Cyclin D1