Immunoexpression of bone morphogenetic protein-2 (BMP-2), BMP receptor type IA, and BMP receptor type II in metastatic and non-metastatic lower lip squamous cell carcinoma.
BACKGROUND
The aim of this study was to evaluate the expression of bone morphogenetic protein-2 (BMP-2), BMPR-IA, and BMPR-II in metastatic and non-metastatic lower lip squamous cell carcinoma (LLSCC).


METHODS
Twenty LLSCC with regional nodal metastasis and 20 LLSCC without metastasis were selected for analysis of the immunoexpression of BMP-2, BMPR-IA, and BMPR-II. The percentage of positive cells was evaluated according to the following parameters: score 1 (staining in 0-50% of cells), score 2 (staining in 51-75% of cells), and score 3 (staining in >75% of cells). Immunostaining intensity was evaluated according to the following scores: score 1 (absent or weak expression) and score 2 (strong expression).


RESULTS
Regarding the percentage of positive cells, most tumors with and without metastasis showed score 3 for both BMP-2 (P = 0.655) and BMPR-IA (P = 0.655). For BMPR-II, metastatic tumors exhibited higher percentage of positive cells in comparison with non-metastatic tumors (P = 0.049). With respect to immunostaining intensity, most LLSCCs with and without metastasis showed score 2 for BMP-2 (P = 1.000) and score 1 for BMPR-II (P = 1.000). For BMPR-IA, most metastatic tumors presented score 2, whereas most non-metastatic tumors showed score 1 (P < 0.001). Strong expression of BMPR-IA showed a statistically significant association with advanced clinical staging (P < 0.001) and high score of malignancy (P = 0.028).


CONCLUSIONS
The results of this study suggest that disturbances in the BMP-2 signaling pathway may be involved in the development of LLSCC and that the strong expression of BMPR-IA might be indicative of the development of metastasis in these lesions.
Oral Pathology Department, Federal University of Rio Grande do Norte, Natal, RN, Brazil.
Cyntia H P
CH
de Carvalho
Cassiano F W
CF
Nonaka
Cristina R F
CR
de Araújo
Lélia B
LB
de Souza
Leão P
LP
Pinto
D055396:Bone Morphogenetic Protein 2 / Q000096:biosynthesis; D052005:Bone Morphogenetic Protein Receptors, Type I / Q000096:biosynthesis; D052006:Bone Morphogenetic Protein Receptors, Type II / Q000096:biosynthesis; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology / Q000556:secondary*; D006801:Humans; D007124:Immunoenzyme Techniques; D008048:Lip Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000556:secondary*; D008207:Lymphatic Metastasis; D015398:Signal Transduction; D018709:Statistics, Nonparametric
D055396:Bone Morphogenetic Protein 2; D052005:Bone Morphogenetic Protein Receptors, Type I; D052006:Bone Morphogenetic Protein Receptors, Type II