Hyaluronidases and hyaluronan synthases expression is inversely correlated with malignancy in lung/bronchial pre-neoplastic and neoplastic lesions, affecting prognosis

Abstract

We collected a series of 136 lung/bronchial and 56 matched lung parenchyma tissue samples from patients who underwent lung/bronchial biopsies and presented invasive carcinoma after lung surgery. The lung/bronchial samples included basal cell hyperplasia, squamous metaplasia, moderate dysplasia, adenomatous hyperplasia, severe dysplasia, squamous cell carcinoma and adenocarcinoma. Matched lung parenchyma tissue samples included 25 squamous cell carcinomas and 31 adenocarcinomas. Immunohistochemistry was performed to analyze for the distribution of hyaluronidase (Hyal)-1 and -3, and hyaluronan synthases (HAS)-1, -2, and -3. Hyal-1 showed significantly higher expression in basal cell hyperplasia than in moderate dysplasia (P=0.01), atypical adenomatous hyperplasia (P=0.0001), or severe dysplasia (P=0.03). Lower expression of Hyal-3 was found in atypical adenomatous hyperplasia than in basal cell hyperplasia (P=0.01) or moderate dysplasia (P=0.02). HAS-2 was significantly higher in severe dysplasia (P=0.002) and in squamous metaplasia (P=0.04) compared with basal cell hyperplasia. HAS-3 was significantly expressed in basal cell hyperplasia compared with atypical adenomatous hyperplasia (P=0.05) and severe dysplasia (P=0.02). Lower expression of HAS-3 was found in severe dysplasia compared with squamous metaplasia (P=0.01) and moderate dysplasia (P=0.01). Epithelial Hyal-1 and -3 and HAS-1, -2, and -3 expressions were significantly higher in pre-neoplastic lesions than in neoplastic lesions. Comparative Cox multivariate analysis controlled by N stage and histologic tumor type showed that patients with high HAS-3 expression in pre-neoplastic cells obtained by lung/bronchial biopsy presented a significantly higher risk of death (HR=1.19; P=0.04). We concluded that localization of Hyal and HAS in lung/bronchial pre-neoplastic and neoplastic lesions was inversely related to malignancy, which implied that visualizing these factors could be a useful diagnostic procedure for suspected lung cancer. Finalizing this conclusion will require a wider study in a randomized and prospective trial.

Figure 1. Hyaluronidase (Hyal)-1 and −3 in basal cell hyperplasia, squamous metaplasia, moderate dysplasia, atypical adenomatous hyperplasia, severe dysplasia, squamous cell carcinoma and adenocarcinoma, as shown by immunohistochemistry staining. Hyal-1 was more prominently expressed by epithelial cells in basal cell hyperplasia than in moderate dysplasia, adenomatous hyperplasia, severe dysplasia, squamous cell carcinoma or adenocarcinoma. Hyal-1 expression decreased and became more dispersed as malignancy increased and epithelial cells became less organized. Strong and diffuse expression of Hyal-3 was seen in atypical adenomatous hyperplasia, basal cell hyperplasia and moderate dysplasia. Arrows and asterisks indicate cytoplasmic expression in epithelial cells of pre-neoplastic and neoplastic tissue. Bar: 100 µm.

Figure 2. Hyaluronan synthases (HAS)-1, −2, and −3 in basal cell hyperplasia, squamous metaplasia, moderate dysplasia, atypical adenomatous hyperplasia, severe dysplasia, squamous cell carcinoma and adenocarcinoma, shown by immunohistochemistry staining. Similar expression of HAS-1 was seen in basal cell hyperplasia, squamous metaplasia, moderate dysplasia, atypical adenomatous hyperplasia and severe dysplasia. Fewer epithelial cells in squamous cell carcinoma and adenocarcinoma expressed HAS-1. Numerous epithelial cells expressed HAS-2 in severe dysplasia compared to basal cell hyperplasia, squamous metaplasia and basal cell hyperplasia. HAS-3 was prominently expressed in basal cell hyperplasia, atypical adenomatous hyperplasia and severe dysplasia. Few epithelial cells expressed HAS-3 in severe dysplasia compared to squamous metaplasia and moderate dysplasia. Arrows and asterisks indicate cytoplasmic expression in epithelial cells of pre-neoplastic and neoplastic tissue. Bar: 100 µm.

Figure 3. Intensity and coverage of Hyal-1 and −3 and HAS-1, −2, and −3 staining in pre-neoplastic, squamous cell carcinoma and adenocarcinoma. See Results section for complete information about statistical comparisons (ANOVA).

Figure 4. Regression plots of survival probability versus follow-up time in months for all patients. The dashed line indicates the group with <27% HAS-3; the solid line indicates the group with >27% HAS-3.