Abstract | | |
Aim: Peripheral giant cell granuloma (PGCG) and central giant cell granuloma (CGCG) of the jaws are benign proliferations of spindle-shaped mesenchymal cells and multinucleated giant cells. Despite the histopathologic similarities, they have markedly different clinical behavior. PGCG shows low recurrence rate whereas CGCG shows a variable clinical behavior ranging from nonaggressive lesions to aggressive lesions characterizing by pain, rapid growth, and high recurrence rate. Therefore, the aim of the study was to compare CGCG with PGCG by immunohistochemistry using Ki-67, osteopontin (OPN), and integrin αvantibodies. Subjects and Methods: Twenty PGCG and 20 CGCG were selected for immunohistochemical evaluation of OPN, integrin αv, and Ki-67 in multinucleated giant cells and mononucleated cells of PGCG and CGCG. Results: PGCG showed higher Ki-67 immunoreactivity in mononucleated cells compared to CGCG (P < 0.05). There was no reactivity with Ki-67 in multinucleated giant cells of both groups. Mononucleated cells in CGCGs demonstrated increased OPN and integrin αvexpressions in comparison with PGCGs (P < 0.05). Conclusions: The clinic behavior of CGCG being more aggressive than PGCG might be explained by the high expression of OPN and integrin αv. Further studies are necessary to evaluate the other OPN receptors and their role on the biologic behavior of these lesions.
Keywords: Central giant cell granuloma, integrin αv, Ki-67, osteopontin, peripheral giant cell granuloma
How to cite this article: Aksakalli N. Evaluation of the osteopontin in oral peripheral and central giant cell granuloma. Indian J Pathol Microbiol 2018;61:18-21 |
Introduction | |  |
Osteopontin (OPN), also known as secreted phosphoprotein 1 (SPP1), is a phosphorylated glycoprotein present in many normal tissues, mediates immune regulation and bone formation. This protein is a chemoattractant to precursors of osteoclasts and can modulate osteoclast activity. OPN is encoded by a gene designated as SPP1 at chromosome 4q21–23. Binding of OPN to the cell surface receptors can affect chemotaxis, attachment, and migration of many cell types. It possesses high affinity to hydroxyapatite and has been shown to promote cell attachment and migration by serving as an attachment substrate for αv-containing integrins. Binding of OPN to osteoclast cell membrane receptor integrin αv can activate the osteoclast and increase its osteolytic activity.[1],[2],[3],[4],[5],[6] It also plays a role in the migration and invasion of transformed epithelial cells.[7]
Ki-67 is a proliferation marker expressed in all active phases of the cell cycle and widely studied in the literature in many tumors and reactive lesions.[8]
Peripheral giant cell granuloma (PGCG) is considered to be a reactive process response to local irritating factor. It mainly occurs on the gingiva, presenting a firm nodule or pediculated mass with color ranging red to purple or red-blue. PGCG may develop at almost any age and tend to be seen more commonly in females than males.[9]
Central giant cell granuloma (CGCG), also called giant cell lesion, is a nonneoplastic bone lesion. The lesion is found predominantly in children and young adults. Most cases occur before 30 years of age and more common in the anterior part of the mandible. Females are more affected than males. Radiologically, the lesions show variable findings, varying from small unilocular lesions to large multilocular lesions with cortical perforation.[9],[10],[11]
Microscopic examination of both lesions consists of multinuclear osteoclast-like giant cells in a background of ovoid, spindle-shaped mesenchymal cells and foci of hemorrhage.[9],[10],[11],[12] Although PGCG and CGCG have histopathologic similarities, they have markedly different clinical behavior. PGCG shows low recurrence rate whereas CGCG shows a variable clinical behavior ranging from nonaggressive lesions to aggressive lesions characterizing by pain, rapid growth, cortical perforation, and high recurrence rate. Therefore, the aim of the study was to compare the immunohistochemical expression of OPN, integrin αv, and Ki-67 in CGCG and PGCG to investigate the possible contribution of these antibodies on the different biologic behavior.
Subjects and Methods | |  |
Samples selection
Formalin-fixed, paraffin-embedded blocks of 20 PGCG and 20 CGCG cases were collected from the files of the department. The samples were reviewed, and the most diagnostic cases with adequate clinical and radiological documentation were selected. Patients with hyperparathyroidism or cherubism were excluded from the study. PGCG consisted of 9 men, 11 women with mean age 45.6, and CGCG consisted of 15 women, 5 men with mean age 31,4. None of the specimens were treated with decalcification process. The study was approved by the Research Ethics Committee of Istanbul University (number: 1350/2012).
Immunohistochemistry
For immunohistochemistry, the paraffin blocks were cut serially into approximately 5 μm thick sections on charged slides. First, the sections were penetrated and dried overnight in an autoclave (56°C). They were deparaffinized with xylene for 30 min and washed with 99% alcohol for 15 min then 96% alcohol and distilled water. Histostain-Plus Bulk Kit (Zymed 2nd Generation, LAB-SA Detection System, 85–9043) was used in this study. For antigen retrieval, the sections were microwaved fourth times for 5 min in citrate buffer (Ph 6.0), cooled to room temperature, and then washed in phosphate-buffered saline for 5 min. Endogenous peroxidase activity was blocked by incubating the sections with 3% H2O2. To prevent nonspesific reactions, sections were incubated with block solution. OPN polyclonal antibody at a dilution of 1:100 (GenTex Inc. 2456 Alton Parkway Irvine, CA, 92606, USA), integrin αv monoclonal antibody at a dilution of 1:50 (Lifespan Biosciences, Inc. 2401 Fourth Avenue Suite 900 Seattle, WA 98121, USA), and Ki-67 antibody at a dilution of 1:50 (Zymed Laboratories, Mouse, Monoclonal, Clone 7B11) were used as primary antibodies. Slides were incubated 120 min with Ki-67 and overnight with OPN and integrin αv. Negative control sections treated with phosphate-buffered antibodies were confirmed to be unstained. The secondary antibody was reacted for 25 min. AEC (ScyTek Laboratories, Inc. 205 South 600 West Logan, UT 84321, USA) chromogen was used to visualize the reaction, and then, the sections were washed in distilled water. Finally, the sections were counterstained with Mayer's hematoxylin, coverslipped, and evaluated with a light microscope by an oral pathologist.
Evaluation methods
The specimens were examined in Olympus BX60 microscope attached to a color video camera (Olympus Analysis Five) which connected to a computer. The number of positive staining was evaluated in multinuclear giant cells (MGCs) and mononuclear (spindle-shaped mesenchymal cells) cells (MCs). Histopathologic slides were gone through at low magnification under a light microscope, and ten areas with the highest degree of staining were selected for cell counts. Results were received as the mean percentage of positive cells, calculated in relation to total cells, determined for each field.
All calculations were performed by the SPSS 11.0 (Statistical Package for Social Science Inc., Chicago IL, USA). The statistical significance of differences in OPN, integrin αv, and Ki-67 reactivity were analyzed by the Mann–Whitney U-test. P < 0.05 was considered statistically significant.
Results | |  |
[Figure 1], [Figure 2], [Figure 3] show representative pictures of OPN, integrin αv, and Ki-67 expressions in CGCG and PGCG, and [Table 1] summarizes the immunohistochemical results. | Figure 1: Immunohistochemical staining for osteopontin. Multinucleated giant cells (arrows) showing strong positivity for osteopontin and mononucleated cells (arrow heads) showing mild to moderate immunostaining in central giant cell granuloma (a) and peripheral giant cell granuloma (b), (original magnification x400, x200, respectively)
Click here to view |
 | Figure 2: Immunohistochemical staining for integrin αvcentral giant cell granuloma (a) showed higher expression of integrin αvin mononucleated cells (arrows) than peripheral giant cell granuloma (b), (original magnification x400, x200, respectively)
Click here to view |
 | Figure 3: Immunohistochemical staining for Ki-67. Mononucleated cells (arrows) expressed higher nuclear staining with Ki-67 in peripheral giant cell granuloma (a) than central giant cell granuloma (b). There was no staining in multinucleated cells (arrow heads) of both groups (original magnification x400)
Click here to view |
 | Table 1: Immunohistochemical analysis of osteopontin, Integrin αv, and Ki-67
Click here to view |
Immunohistochemical staining for osteopontin
OPN immunostaining was observed in the cytoplasm and membrane of MCs and MGCs in CGCG and PGCG. No differences were detected between MGCs of both lesions. OPN expression in MCs of CGCG was significantly higher than MCs of PGCG (P = 0.018).
Immunohistochemical staining for integrin αv
Expression of integrin αv is also observed in the cells of both groups. However, there were no statistically significant differences in MGCs component of both groups. MCs of CGCG exhibited increased number of integrin αv-positive cells when compared with MCs of PGCG (P = 0.007).
Immunohistochemical staining for Ki-67
Although MCs are the proliferative compartment responsible for the biologic activity in giant cell-containing lesions, MGCs were also evaluated for Ki-67 staining. PGCG showed higher Ki-67 immunoreactivity in MCs compared to CGCG (P = 0.043). There was no reactivity with Ki-67 in MGCs of both groups.
Discussion | |  |
PGCG and CGCG share the same histopathologic features. Therefore, some investigators believe that PGCG may represent a soft tissue counterpart of CGCG. PGCG is a reactive lesion associated with a local irritating factor. CGCG is widely considered reactive lesion with unknown etiology. PGCG shows low recurrence after surgical treatment whereas CGCG presents a variable clinical behavior ranging from nonaggressive lesions to aggressive lesions characterizing by pain, rapid growth, cortical perforation, and high recurrence rate.[9]
The primary cells of both lesions are spindle-shaped mesenchymal cells which are the proliferative compartment responsible for the biologic activity in giant cell-containing lesions.[13] Although CGCG is known to have high rate recurrence and aggressive behavior compared with PGCG, it showed a lower number of Ki-67-positive cells in comparison with the latter in our study. These results are not consistent with the clinical behavior of these lesions; therefore, we suggest that other factors can influence the biologic behavior of the lesions. In other words, biologic activity might not be strictly associated with proliferation marker. This result was in agreement with Souza et al.[14]
This study showed that a high positive OPN staining in these lesions. OPN protein was majorly expressed in MGCs of both groups, but the positivity also observed in MCs. There was significantly higher number of OPN-positive cells observed in MCs of CGCG than PGCG whereas there was no difference between MGCs of the groups. Our findings suggest that the mesenchymal cells probably synthesize and secrete OPN protein which is associated with bone remodeling. OPN belongs to the small integrin-binding ligand N-linked glycoprotein family, which also includes bone sialoprotein, dentin matrix protein 1, dentin sialophosphoprotein, and matrix extracellular phosphoglycoprotein.[15] These proteins are frequently seen in sclerotic bone metastasis, especially breast and prostate cancers.[1],[16]
Integrin αv expression was also evaluated in the study. Binding of OPN to cell membrane receptor integrin αv on the osteoclast can activate the osteoclast and increase its osteolytic activity.[17],[18] High expression of this protein in CGCG than PGCG was compatible with their clinical behavior.
Multinucleated giant cells are the secondary cells which are more prominent microscopically. These cells are considered to be formed from the fusion of monocyte/macrophage precursors differentiated into osteoclasts under the influence of cytokines.[19],[20] The expressions of OPN, integrin αv, and Ki-67 were similar in MGCs of both groups. Therefore, our study also suggests that MGCs have not any role in their biological behavior of these lesions, although the terms of the lesions are derived from this cell type.
There are some studies about OPN and integrin αv expressions in odontogenic lesions.[1],[21] However, to the best of our knowledge, this is the first study regarding the evaluation of these proteins by both multinucleated and mesenchymal cells in PGCG and CGCG of the jaws.
Conclusions | |  |
The clinic behavior of CGCG being more aggressive than PGCG might be explained by the high expression of OPN and integrin αv. Further studies are necessary to evaluate the other OPN receptors and their role on the biologic behavior of these lesions.
Acknowledgment
I want to thank Dr. Merva Soluk Tekkesin for valuable consideration of the paper.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References | |  |
1. | Wang YP, Liu BY. Expression of osteopontin and its receptors in ameloblastomas. Oral Oncol 2009;45:538-42.  [ PUBMED] |
2. | Martinez C, Churchman M, Freeman T, Ilyas M. Osteopontin provides early proliferative drive and may be dependent upon aberrant c-myc signalling in murine intestinal tumours. Exp Mol Pathol 2010;88:272-7.  [ PUBMED] |
3. | Sodek J, Ganss B, McKee MD. Osteopontin. Crit Rev Oral Biol Med 2000;11:279-303.  [ PUBMED] |
4. | Schack L, Stapulionis R, Christensen B, Kofod-Olsen E, Skov Sørensen UB, Vorup-Jensen T, et al. Osteopontin enhances phagocytosis through a novel osteopontin receptor, the alphaXbeta2 integrin. J Immunol 2009;182:6943-50. |
5. | Salehinejad J, Saghafi S, Sharifi N, Zare-Mahmoodabadi R, Saghravanian N, Ghazi N, et al. Evaluation of osteopontin and CD44v6 expression in odontogenic cystic lesions by immunohistochemistry. Pathol Res Pract 2012;208:410-4.  [ PUBMED] |
6. | Sodek J, Batista Da Silva AP, Zohar R. Osteopontin and mucosal protection. J Dent Res 2006;85:404-15.  [ PUBMED] |
7. | Chien CY, Su CY, Chuang HC, Fang FM, Huang HY, Chen CH, et al. Comprehensive study on the prognostic role of osteopontin expression in oral squamous cell carcinoma. Oral Oncol 2009;45:798-802 |
8. | Scholzen T, Gerdes J. The ki-67 protein: From the known and the unknown. J Cell Physiol 2000;182:311-22. |
9. | Neville BW, Damm DD, Allen CM, Bouquot JE, editors. Oral and Maxillofacial Pathology. 3 th ed. Missouri: Saunders Elsevier; 2009. p. 520-1, 626-8. |
10. | Sun ZJ, Cai Y, Zwahlen RA, Zheng YF, Wang SP, Zhao YF, et al. Central giant cell granuloma of the jaws: Clinical and radiological evaluation of 22 cases. Skeletal Radiol 2009;38:903-9. |
11. | Kruse-Lösler B, Diallo R, Gaertner C, Mischke KL, Joos U, Kleinheinz J, et al. Central giant cell granuloma of the jaws: A clinical, radiologic, and histopathologic study of 26 cases. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2006;101:346-54. |
12. | Itonaga I, Hussein I, Kudo O, Sabokbar A, Watt-Smith S, Ferguson D, et al. Cellular mechanisms of osteoclast formation and lacunar resorption in giant cell granuloma of the jaw. J Oral Pathol Med 2003;32:224-31.  [ PUBMED] |
13. | Flórez-Moreno GA, Henao-Ruiz M, Santa-Sáenz DM, Castañeda-Peláez DA, Tobón-Arroyave SI. Cytomorphometric and immunohistochemical comparison between central and peripheral giant cell lesions of the jaws. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2008;105:625-32. |
14. | Souza PE, Mesquita RA, Gomez RS. Evaluation of p53, PCNA, ki-67, MDM2 and AgNOR in oral peripheral and central giant cell lesions. Oral Dis 2000;6:35-9.  [ PUBMED] |
15. | Chen Q, Shou P, Zhang L, Xu C, Zheng C, Han Y, et al. An osteopontin-integrin interaction plays a critical role in directing adipogenesis and osteogenesis by mesenchymal stem cells. Stem Cells 2014;32:327-37. |
16. | Carlinfante G, Vassiliou D, Svensson O, Wendel M, Heinegård D, Andersson G, et al. Differential expression of osteopontin and bone sialoprotein in bone metastasis of breast and prostate carcinoma. Clin Exp Metastasis 2003;20:437-44. |
17. | Miyauchi A, Alvarez J, Greenfield EM, Teti A, Grano M, Colucci S, et al. Binding of osteopontin to the osteoclast integrin alpha v beta 3. Osteoporos Int 1993;3 Suppl 1:132-5. |
18. | Ross FP, Chappel J, Alvarez JI, Sander D, Butler WT, Farach-Carson MC, et al. Interactions between the bone matrix proteins osteopontin and bone sialoprotein and the osteoclast integrin alpha v beta 3 potentiate bone resorption. J Biol Chem 1993;268:9901-7. |
19. | Liu B, Yu SF, Li TJ. Multinucleated giant cells in various forms of giant cell containing lesions of the jaws express features of osteoclasts. J Oral Pathol Med 2003;32:367-75. |
20. | Papanicolaou P, Chrysomali E, Stylogianni E, Donta C, Vlachodimitropoulos D. Increased TNF-α, IL-6 and decreased IL-1β immunohistochemical expression by the stromal spindle-shaped cells in the central giant cell granuloma of the jaws. Med Oral Patol Oral Cir Bucal 2012;17:e56-62. |
21. | Wang YP, Liu BY. High expression of osteopontin and CD44v6 in odontogenic keratocysts. J Formos Med Assoc 2009;108:286-92. |

Correspondence Address: Nihan Aksakalli Department of Tumour Pathology, Istanbul University, Institute of Oncology, Block A, Floor 2 Capa, 34093, Istanbul Turkey
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/IJPM.IJPM_214_16

[Figure 1], [Figure 2], [Figure 3]
[Table 1] |