Growth of oral and skin fibroblasts from patients with oral submucous fibrosis.

The purpose of the investigation was to evaluate and compare the proliferation (growth) of mouth fibroblasts and skin fibroblasts from patients with oral submucous fibrosis (OSF). Material comprised fibroblasts from fibrous bands situated in the buccal mucosa and from the inner aspect of the forearm of 8 patients with classic features of OSF as well as fibroblasts from 6 buccal mucosa and 8 skin biopsy specimens from healthy non-areca nut chewing individuals. Cells were cultured for 8 days according to standard techniques. Their growth was monitored daily, under optimal conditions as well as exposure to concentrations of arecoline. The data were analyzed using regression analysis, analysis of variance and the Kruskal-Wallis test. We found no statistically significant differences between the proliferation patterns of oral and skin fibroblasts from patients or between those from patients and controls. The reaction of the cells exposed to concentrations of arecoline was similar; at low concentrations (0.1-10 micrograms/ml) normal growth was maintained, while 100 micrograms/ml inhibited growth. It is concluded that fibroblasts from mouths affected by OSF have proliferation patterns which fall within normal parameters, that the excessive collagen formation in established OSF is not due to increased fibroblast proliferation and that arecoline does not stimulate fibroblast proliferation.

Effect of chilli (Capsicum frutescens) extract on proliferation of oral mucosal fibroblasts.

Various concentrations of chilli extract were tested in 2 stages on the growth of a human buccal mucosa fibroblast cell line. Firstly, concentrations of 25, 75, 150 and 300 micrograms/ml were tested on the cell line for 6 days followed by a repeat which included concentrations of 400 and 500 micrograms/ml. In the latter, cell growth was monitored for 18 days. From day 3 (72 hr) suppression of cell growth was evident with concentrations 300-500 micrograms/ml. Total cell death occurred at 16 days with 300 micrograms/ml and at 6 days with 400-500 micrograms/ml. With the lower concentrations, 25-150 micrograms/ml, the daily counts were lower than the control but the difference was not statistically significant. Growth continued unabated. It is therefore concluded that cytopathic effect of chilli extract to fibroblasts is concentration dependent.

Observations on the effect of areca nut extracts on oral fibroblast proliferation.

The effects of aqueous extracts of raw, baked and boiled areca nuts were tested on cultured human buccal mucosa fibroblasts. Cells were exposed to extract concentrations of 0, 50, 100, 150, 300 and 500 micrograms/ml. The arecoline and arecaidine content was determined in the extracts with HPLC and raw nut contained 5.5% m/m, baked nut 6.6% m/m and boiled nut 7.1% m/m. Extract concentrations of 50 to 150 micrograms/ml inhibited cell growth in a concentration-dependent manner but did not lead to total cell death during a 7 day period. However, total cell death did occur with concentrations of 300 and 500 micrograms/ml. It is concluded that areca nut extract is toxic to cultured fibroblasts and inhibits their proliferation in a concentration-dependent manner.

HLA-antigens in oral submucous fibrosis.

HLA-typing was carried out on 122 areca nut chewers who attended hospitals for complaints unrelated to the habit. The subjects were South Africans of Indian extraction. The study did not include haplotypes. Palpable fibrous bands in the mouth indicated oral submucous fibrosis. The subjects were divided into 4 groups based on specific oral symptoms and signs. Groups A and B were without fibrous bands. Group A (47 subjects) included those with one or no symptoms while group B (28 subjects) suffered from 2 to 7 oral symptoms. Group C (17 subjects) had oral symptoms and represented early or mild oral submucous fibrosis and exhibited at least one discrete palpable fibrous band. Group D (30 subjects) were classic oral submucous fibrosis cases with multiple bands. The high occurrence of oral submucous fibrosis in this study group (39%) is similar to the occurrence in comparable age groups reported earlier in South Africa and is conceivably due to the higher age range of the subjects and their relatively long exposure to the areca nut. We were unable to demonstrate a specific pattern of HLA-antigen frequencies in chewers with or without the disease. Furthermore, there were no differences between the study population and the controls. It is concluded that there is not necessarily a HLA-associated susceptibility in oral submucous fibrosis.

The areca nut chewing habit and oral squamous cell carcinoma in South African Indians. A retrospective study.

A retrospective study (1983-1989) of oral squamous carcinomas and concomitant oral habits was undertaken in South African Indians from Natal. Information came from hospital records and interviews with patients, families and friends. There were 143 oral squamous carcinomas; these occurred in a ratio of 1:1,6 for men and women respectively. Squamous carcinomas of the cheek (buccal mucosa, alveolar sulcus and gingiva) occurred most frequently, especially in women (57/89--64%), while in men tongue cancer predominated (22/54--41%). Ninety-three per cent of women (83/87) and 17% of men (9/54) habitually chewed the areca nut. Thirty-nine of 57 women (68%) with cheek cancer and 21/25 (84%) with tongue cancer only chewed the nut (no tobacco, snuff or smoking). Analyses confirmed an association between nut chewing and cheek cancer. The odds ratio (OR) for oral cancer in women 25 years and older who only chewed the nut was 43,9 and the attributable risk (AR) 0,89 (89%). With tobacco the OR increases to 47,42 and the AR to 0,91 (91%). The data showed that the areca nut habit with or without tobacco use is important in the development of oral squamous carcinoma. Elimination of this habit can reduce the risk in these women substantially (89-91%) if all other factors remain the same.