HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 295/1/F82    most recent 00091.2008v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (4) Citing Articles via Google Scholar Google Scholar Articles by Li, M. Articles by Batuman, V. Search for Related Content PubMed PubMed Citation Articles by Li, M. Articles by Batuman, V.

Silencing megalin and cubilin genes inhibits myeloma light chain endocytosis and ameliorates toxicity in human renal proximal tubule epithelial cells

Section of Nephrology and Hypertension, Department of Medicine, Tulane University School of Medicine, New Orleans, Louisiana

Submitted 21 February 2008 ; accepted in final form 26 April 2008

Using target-specific short interfering (si) RNAs, we silenced the tandem endocytic receptors megalin and cubilin genes in cultured human renal proximal tubule epithelial cells. Transfection by siRNA resulted in up to 90% suppression of both megalin and cubilin protein and mRNA expression. In HK-2 cells exposed to -light chain for up to 24 h, light chain endocytosis was reduced in either megalin- or cubilin-silenced cells markedly but incompletely. Simultaneous silencing of both the cubilin and megalin genes, however, resulted in near-complete inhibition of light chain endocytosis, as determined by measuring -light chain protein concentration in cell cytoplasm and by flow cytometry using FITC-labeled -light chain. In these cells, light chain-induced cytokine responses (interleukin-6 and monocyte chemoattractant protein-1) and epithelial-to-mesenchymal transition as well as the associated cellular and morphological alterations were also markedly suppressed. The results demonstrate that light chain endocytosis is predominantly mediated by the megalin-cubilin tandem endocytic receptor and identify endocytosis as a key step in light chain cytotoxicity. Blocking light chain endocytosis prevents its nephrotoxic effects on human kidney proximal tubule cells.

myeloma kidney; RNA interference; nephrotoxicity; flow cytometry; receptor-mediated endocytosis

This article has been cited by other articles:

				D. F. Balkovetz, P. Chumley, and H. Amlal Downregulation of claudin-2 expression in renal epithelial cells by metabolic acidosis Am J Physiol Renal Physiol, September 1, 2009; 297(3): F604 - F611. [Abstract] [Full Text] [PDF]

				Y. Iwao, K. Nakajou, R. Nagai, K. Kitamura, M. Anraku, T. Maruyama, and M. Otagiri CD36 is one of important receptors promoting renal tubular injury by advanced oxidation protein products Am J Physiol Renal Physiol, December 1, 2008; 295(6): F1871 - F1880. [Abstract] [Full Text] [PDF]