Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2015 Mar;106(3):315-23.
doi: 10.1111/cas.12601. Epub 2015 Feb 17.

Distinctive expression patterns of glycoprotein non-metastatic B and folliculin in renal tumors in patients with Birt-Hogg-Dubé syndrome

Mitsuko Furuya  1 , Seung-Beom Hong, Reiko Tanaka, Naoto Kuroda, Yoji Nagashima, Kiyotaka Nagahama, Takahito Suyama, Masahiro Yao, Yukio Nakatani
Affiliations

Distinctive expression patterns of glycoprotein non-metastatic B and folliculin in renal tumors in patients with Birt-Hogg-Dubé syndrome

Mitsuko Furuya et al. Cancer Sci. 2015 Mar.

Abstract

Birt-Hogg-Dubé syndrome (BHD) is an inherited disorder associated with a germline mutation of the folliculin gene (FLCN). The affected families have a high risk for developing multiple renal cell carcinomas (RCC). Diagnostic markers that distinguish between FLCN-related RCC and sporadic RCC have not been investigated, and many patients with undiagnosed BHD fail to receive proper medical care. We investigated the histopathology of 27 RCCs obtained from 18 BHD patients who were diagnosed by genetic testing. Possible somatic mutations of RCC lesions were investigated by DNA sequencing. Western blotting and immunohistochemical staining were used to compare the expression levels of FLCN and glycoprotein non-metastatic B (GPNMB) between FLCN-related RCCs and sporadic renal tumors (n = 62). The expression of GPNMB was also evaluated by quantitative RT-PCR. Histopathological analysis revealed that the most frequent histological type was chromophobe RCC (n = 12), followed by hybrid oncocytic/chromophobe tumor (n = 6). Somatic mutation analysis revealed small intragenic mutations in six cases and loss of heterozygosity in two cases. Western blot and immunostaining analyses revealed that FLCN-related RCCs showed overexpression of GPNMB and underexpression of FLCN, whereas sporadic tumors showed inverted patterns. GPNMB mRNA in FLCN-related RCCs was 23-fold more abundant than in sporadic tumors. The distinctive expression patterns of GPNMB and FLCN might identify patients with RCCs who need further work-up for BHD.

Keywords: Birt-Hogg-Dubé syndrome (BHD); familial cancer; folliculin (FLCN); glycoprotein non-metastatic B (GPNMB); renal tumor.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Histological and gross features of FLCN-related renal tumors. (a, b) H&E staining of chromophobe renal cell carcinoma (RCC) in Birt–Hogg–Dubé (BHD) syndrome patient BHD13 (a) and hybrid oncocytic/chromophobe tumor (HOCT) in BHD5 (b). A few benign-looking cystic tubules migrated in tumor nodules (arrows). (c, d) High magnification of chromophobe RCC in BHD17 (c) and HOCT in BHD10 (d). HOCT is composed of oncocytoma-like granular cells with round nuclei and chromophobe RCC-like cell borders and perinuclear halo. (e) Sectioned surface of BHD7 shows a brownish solid tumor. (f, g) H&E staining of papillary RCC in BHD7 at low magnification (f) and high magnification (g). (h) Tumor cells were diffusely immunostained for α-methylacyl-CoA racemase, supporting the histology of papillary RCC.
Figure 2
Figure 2
Germline and somatic mutation patterns of FLCN. (a) Birt–Hogg–Dubé (BHD) syndrome patient BHD9 carried FLCN germline mutation in exon 11 (upper left). The exon 10 sequence was confirmed to be wild-type (lower left). The patient's tumor BHD9-T2 showed somatic mutation in exon 10 (lower right) in addition to germline mutation (upper right). (b) BHD17 carried FLCN germline mutation in exon 11 (left). The mutation pattern was c.1285dupC. In the tumor lesion, heterozygous mutation in the C8 tract was completely replaced by a C9 tract, indicating loss of heterozygosity (right). No additional mutation was found in the other exons. Arrows indicate starting point of mutation.
Figure 3
Figure 3
Folliculin (FLCN) expression in Birt–Hogg–Dubé (BHD) and sporadic tumors. (a) Representative results of Western blot analysis of BHD kidneys. Patients BHD9 and BHD17 had two independent tumors (T1, T2). The FLCN bands (70 kDa) were clearly detected in non-tumor lanes but barely seen in tumor lanes. N, normal-looking region; T, tumor region. (b) Representative results of Western blotting analysis of sporadic renal tumors and normal kidneys without the background of BHD. Sporadic renal tumors include clear cell renal cell carcinomas (RCCs) (n = 3), oncocytoma (n = 1), papillary RCC (n = 1), and chromophobe RCCs (n = 3).
Figure 4
Figure 4
Folliculin (FLCN) immunostaining in normal kidney, and Birt–Hogg–Dubé (BHD) and sporadic tumors. (a) H&E staining of a normal kidney. (b) Serial section of sample A immunostained for FLCN. Nuclei of distal tubules were strongly positive for FLCN. (c–h) Immunostaining for FLCN in BHD and sporadic tumors. Weak cytoplasmic staining was evident in tumors of BHD patients (c, e, h). Insets highlight distal tubules of non-tumor areas, showing immunoreactivity to FLCN. Sporadic renal tumors (d, f, h) showed strong nuclear staining.
Figure 5
Figure 5
Glycoprotein non-metastatic B (GPNMB) expression in Birt–Hogg–Dubé (BHD) and sporadic tumors. (a) Expression levels of GPNMB mRNA were analyzed by quantitative RT-PCR as shown. Sporadic renal tumors include clear cell renal cell carcinomas (RCCs) (n = 9), oncocytoma (n = 1), papillary RCC (n = 1), and chromophobe RCCs (n = 6). (b) Representative results of Western blot analysis of BHD kidneys. Patients BHD9 and BHD17 had two independent tumors (T1, T2), respectively. Two isoforms (115 kDa and 80 kDa) of GPNMB bands were seen in tumor lanes, but not in normal-looking lanes. N, normal-looking region; T, tumor region. (c) Representative results of Western blot analysis of sporadic renal tumors and normal kidneys without the background of BHD. GPNMB bands were barely seen in sporadic tumor and normal kidney lanes. Sporadic renal tumors included clear cell RCCs (n = 3), oncocytoma (n = 1), papillary RCC (n = 1), and chromophobe RCCs (n = 4). PC, positive control using BHD9-T2.
Figure 6
Figure 6
Glycoprotein non-metastatic B (GPNMB) immunostaining of Birt–Hogg–Dubé (BHD) and sporadic tumors. (a, c, e) H&E staining of BHD tumors (T) of patients BHD2-T1 (a), BHD13-T1 (c), and a nodule of oncocytosis in the normal-looking region (N) of BHD13 (e, dotted circle). (b, d, f) Serial sections of (a, c, e) immunostained for GPNMB. Tumor cells (b, d) were intensely stained for GPNMB. Tubules of normal-looking regions were negative for GPNMB. GPNMB was immunostained in the region of focal oncocytosis (f, dotted circle). (g–i) Immunostaining for GPNMB in sporadic renal tumors: papillary renal cell carcinoma (g), oncocytoma (h), and chromophobe renal cell carcinoma (i). Insets are H&E stains of the serial sections.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Menko FH, van Steensel MA, Giraud S, et al. Birt–Hogg–Dube syndrome: diagnosis and management. Lancet Oncol. 2009;10:1199. - PubMed
    1. Toro JR, Wei MH, Glenn GM, et al. BHD mutations, clinical and molecular genetic investigations of Birt–Hogg–Dube syndrome: a new series of 50 families and a review of published reports. J Med Genet. 2008;45:321. - PMC - PubMed
    1. Nickerson ML, Warren MB, Toro JR, et al. Mutations in a novel gene lead to kidney tumors, lung wall defects, and benign tumors of the hair follicle in patients with the Birt–Hogg–Dube syndrome. Cancer Cell. 2002;2:157. - PubMed
    1. Zbar B, Alvord WG, Glenn G, et al. Risk of renal and colonic neoplasms and spontaneous pneumothorax in the Birt–Hogg–Dube syndrome. Cancer Epidemiol Biomarkers Prev. 2002;11:393. - PubMed
    1. Pavlovich CP, Walther MM, Eyler RA, et al. Renal tumors in the Birt–Hogg–Dube syndrome. Am J Surg Pathol. 2002;26:1542. - PubMed

Publication types

LinkOut - more resources