Expression of DLC-1 in clear cell renal cell carcinoma: prognostic significance for progression and metastasis.
BACKGROUND
Metastatic renal cell carcinoma (RCC) remains the leading cause of mortality in patients with clear cell RCC. While deleted in liver cancer (DLC-1) is known to be closely associated with tumor growth and metastasis in several kinds of human tumors, the function of DLC-1 in clear cell RCC is unclear.


METHODS
We quantified DLC-1 mRNA expression in paired tumor and non-tumor samples from 62 patients in clear cell RCC using a real-time reverse transcription polymerase chain reaction (RT-PCR), and DLC-1 protein using Western blotting and immunohistochemistry. The association between DLC-1 and matrix metalloproteinase-2 were analyzed.


RESULTS
A high level of DLC-1 mRNA and protein expression in approximately 90% of normal renal specimens, the expression levels of DLC-1 in the primary tumors with synchronous metastases were lower than in those without metastases (p < 0.01). Furthermore, DLC-1 expression inversely correlated with advanced histological grade and stage (p < 0.05). Moreover, it is likely that down-regulated DLC-1 increases matrix invasion abilities of RCC via enhancing matrix metalloproteinase-2 expression.


CONCLUSIONS
Together, it seems that reduced DLC-1 is involved in tumor expansion phenomena associated with tumor progression, invasion and distant metastasis of RCC.
Zhang
Tao
T
Department of Laboratory Medicine, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, PR China.
Zheng
Jingcun
J
Liu
Chunfang
C
Lu
Yuan
Y
D002292:Carcinoma, Renal Cell / Q000378:metabolism* / Q000556:secondary*; D018450:Disease Progression; D005260:Female; D020690:GTPase-Activating Proteins; D006801:Humans; D007680:Kidney Neoplasms / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D025521:Tumor Suppressor Proteins / Q000096:biosynthesis*
C112352:DLC1 protein, human; D020690:GTPase-Activating Proteins; D025521:Tumor Suppressor Proteins