RON proto-oncogene

The RON proto-oncogene is a tyrosine kinase receptor, the ligand for macrophage stimulating protein. This ligand stimulates proliferation and motility while inhibiting apoptosis. Over-expression has been demonstrated in a number of human tumours. A mutant auto-activating form of RON may confer high metastatic potential¹.

Immunohistochemical expression

A study using Western blot analysis showed strong expression in renal oncocytomas but not in other renal tumours.

		negative	weak	moderate	strong	positive, NOS
	Oncocytoma	0/702	1/702	18/702, 3/12 (granular [eosinophilic] variant, cytoplasmic and/or membrane staining)3	51/702, 9/12 (granular [eosinophilic] variant, cytoplasmic and/or membrane staining)3	18/181
	Chromophobe cell carcinoma	0/572	2/572	8/572, 5/11 (cytoplasmic and/or membrane)3	47/572, 6/11 (cytoplasmic and/or membrane)3	0/51
	Clear cell carcinoma	19/632, 3/6 (granular [eosinophilic] variant)3	40/632, 3/6 (granular [eosinophilic] variant, cytoplasmic with or without membrane staining)3	3/632	1/632	0/191
	Papillary cell carcinoma	0/382	24/382	14/382	0/382	0/71
	Poor differentiated carcinoma with sarcomatoid areas					0/11

Diagnostic utility

RON immunoreactivity is of NO value in differentiating renal oncocytoma from chromophobe cell carcinoma.

References

¹Rampino, T., M. Gregorini, et al. (2003). "The Ron proto-oncogene product is a phenotypic marker of renal oncocytoma." Am J Surg Pathol 27(6): 779-85.

²Patton, K. T., M. S. Tretiakova, et al. (2004). "Expression of RON Proto-oncogene in Renal Oncocytoma and Chromophobe Renal Cell Carcinoma." Am J Surg Pathol 28(8): 1045-50. (study used tissue microarrays)

³ Wang HY,Mills SE. KIT and RCC are useful in distinguishing chromophobe renal cell carcinoma from the granular variant of clear cell renal cell carcinoma. Am J Surg Pathol 2005; 29:640-6

This page last revised 17.7.2005.

©SMUHT/PW Bishop