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Expression of Androgen Receptor, Epidermal Growth Factor Receptor, and Transforming Growth Factor  in Salivary Duct Carcinoma
Chun-Yang Fan, MD, PhD;
Mona F. Melhem, MD;
A. Sefik Hosal, MD;
J. Rubin Grandis, MD;
E. Leon Barnes, MD
Arch Otolaryngol Head Neck Surg. 2001;127:1075-1079.
ABSTRACT
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Background Salivary duct carcinoma (SDC) is a rare, highly aggressive neoplasm
that primarily affects the major salivary glands. It is a distinct clinicopathological
entity characterized by its morphologic resemblance to ductal carcinoma of
the breast, a high incidence of regional lymph node metastasis, and distant
dissemination. Frequent expression of androgen receptor (AR) but not estrogen
receptor or progesterone receptor in SDCs suggests that SDC bears a close
immunophenotypic homology with prostatic carcinoma. An AR-mediated autocrine
growth pathway consisting of epidermal growth factor receptor (EGFR) and its
ligand, transforming growth factor  (TGF-), has been implicated
in the carcinogenesis of prostatic carcinoma. Androgens, in the presence of
AR, mediate their mitogenic effects on prostatic cancer cells by up-regulating
the transcriptional and translational activities of EGFR and TGF-.
Through an autocrine mode of action, TGF- produced in the tumor cells
binds to its receptor, EGFR, which is also expressed by these cells, resulting
in a proliferative response.
Objective To investigate whether a TGF-/EGFR autocrine pathway is present
in SDCs.
Design Retrospective analysis of the expression of AR, EGFR, and TGF-
in 12 SDCs.
Setting An academic medical center.
Results Salivary duct carcinoma expresses AR, TGF-, and EGFR in 11 (92%),
8 (67%), and 11 (92%) of 12 cases, respectively.
Conclusion An AR-mediated TGF-/EGFR autocrine pathway may be implicated
in the tumorigenesis of SDC.
INTRODUCTION
GROWTH FACTORS are thought to be involved in the formation and progression
of cancer. Studies1 have demonstrated a decreased
growth factor requirement for proliferation of transformed neoplastic cells
cultured in serum-free media. The loss of requirement for specific growth
factors is a common finding in many types of cancer cells2
and could be mediated by the activation of autologous growth factor synthesis
(autocrine activation).
Transforming growth factor (TGF-) can recognize its cellular
receptor, epidermal growth factor receptor (EGFR), and is produced by a variety
of human tumors.3 High levels of TGF-
and EGFR are detected in epithelial tumors, particularly renal and squamous
cell carcinomas.3 The production of TGF-
by human tumors points to the fact that it may play an important role in tumor
cell growth.
It is hypothesized that TGF- contributes to carcinogenesis via
an autocrine mechanism whereby the growth factor helps sustain the transformed
character of the same cell population from which it is secreted.4
In addition to this function, it has also been shown that TGF- is able
to transform cells.5 Androgen-mediated autocrine
or paracrine mechanisms by which TGF- and EGFR exert their mitogenic
effects in prostatic cancer have been demonstrated by various groups.6-7
Salivary duct carcinoma (SDC) is a rare but clinically highly aggressive
adenocarcinoma of salivary origin that has a striking resemblance to breast
carcinoma of the ductal type, with intraductal and invasive components. However,
by immunohistochemical staining, SDCs frequently express androgen receptor
(AR) (92%)8-9 and, occasionally,
2 prostatic-specific markers, prostatic acid phosphatase (58%) and prostatic-specific
antigen (17%),9 and only rarely estrogen receptor
and progesterone receptor (1% and 6%, respectively).9
Thus, this immunophenotypic profile suggests that SDC may be more reminiscent
of prostatic carcinoma despite its morphologic resemblance to breast cancer.
The present study aims to demonstrate that a TGF-/EGFR autocrine
pathway operative in prostatic carcinoma is also present in SDC.
MATERIALS AND METHODS
TISSUE SPECIMENS
The Medical Archival System was used to retrieve 12 cases of SDC with
available microscopic slides and paraffin-embedded tissue blocks between 1990
and 1997 from the surgical pathology files of the University of Pittsburgh
Medical Center, Pittsburgh, Pa. Three control samples were obtained from parotidectomy
specimens for pleomorphic adenoma of the parotid gland. In all cases, the
tissue sections were fixed in 10% buffered formalin, routinely processed,
embedded in paraffin, sectioned at 5 µm, and stained with hematoxylin-eosin.
Hematoxylin-eosin–stained slides of all 12 cases were reviewed to confirm
the diagnosis and to select the most representative section for immunostaining.
All 12 cases were used in our previous study on immunostaining profile for
AR, prostatic acid phosphatase, and prostatic-specific antigen.9
IMMUNOHISTOCHEMICAL TECHNIQUES
Immunohistochemical studies were performed on formalin-fixed, paraffin-embedded
tissues sectioned at 5 µm with antibodies against human TGF-
(clone 2; Oncogene Science, Cambridge, Mass), human EGFR (clone 1; Genosys
Biotechnologies, The Woodlands, Tex), and human AR (Biogenex Laboratories,
San Ramon, Calif). The positive controls were derived from skin for TGF-,
breast carcinoma for EGFR, and prostatic carcinoma for AR. Negative controls
consisted of a matched primary antibody of unrelated specificity. The standard
avidin-biotin-peroxidase technique was used for all antibodies in this study.10 Antigen retrieval with microwave treatment was used
in immunostaining.11 The immunostaining was
assessed semiquantitatively, with minus sign indicating negative and single
to quadruple plus signs indicating increasing intensities of positive staining.
All sections were counterstained with hematoxylin.
RESULTS
CLINICAL FEATURES
The patient population consisted of 7 men and 5 women who ranged in
age from 36 to 90 years, with a mean age of 66.2 years. Eleven tumors arose
in the parotid gland. One presented as facial nerve paralysis, and, therefore,
only a facial nerve biopsy was done. Most patients presented with clinical
stage IV disease. Regional lymph node metastasis was found in 7 cases (58%)
at presentation. Local recurrence was found in 1 patient and distant metastasis
in 2 patients. These 3 patients died of their disease at 6, 13, and 14 months,
after the diagnosis. Five patients without local recurrence or distant metastasis
are alive with no evidence of disease at a mean interval of 28.8 months (range,
13-44 months) after the diagnosis. Four patients were lost to follow-up. The
clinical features are summarized in Table
1.
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Table 1. Clinical Features of Salivary Duct Carcinoma*
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PATHOLOGIC RESULTS
On gross examination, the tumors ranged from 1.0 to 5.5 cm, with a mean
size of 2.9 cm. Most were gray-white, gritty, firm, and poorly circumscribed,
with frequent invasion into the adjacent normal salivary gland tissue. There
were 3 cases in which SDC arose from a preexisting pleomorphic adenoma (cases
1, 4, and 7). In these cases, the tumors appeared well circumscribed and lobulated
but without a true fibrous capsule. Microscopically, both intraductal and
infiltrating ductal carcinomas were seen. The intraductal components displayed
a variety of growth patterns, including solid, papillary, cystic, and cribriform.
Extensive central comedonecrosis was seen in association with the intraductal
components. The infiltrating ductal carcinoma consisted of irregular glands
and cords of compressed cells, which were frequently associated with a prominent
desmoplastic reaction. Both the intraductal and infiltrating components were
reminiscent of those seen in breast carcinomas. Extensive intraneural and
perineural invasion were seen in 9 (75%) of 12 cases. Angiolymphatic permeation
was also very common, with cervical lymph node metastasis in 7 (58%) of 12
cases.
DETECTION OF AR, EGFR, AND TGF- EXPRESSION IN SDC
Expression of AR in a variety of human tissues has been previously investigated
using immunohistochemical techniques.12 In
this study, AR expression was absent in the nuclei of normal parotid acini
and ductal epithelium (Figure 1,
A) except for focal faint cytoplasmic staining (Figure 1, 1A). In carcinoma cells, intense immunostaining for AR
was found in more than 90% of the tumor cells in 11 (92%) of 12 cases, mainly
localized to the nuclei (Figure 1,
1B). The immunohistochemical staining results for AR are summarized in Table 2. Ten cases in this study were previously
analyzed for AR expression using semiquantitative scoring of the staining
intensity.8
Transforming growth factor is expressed in a variety of normal
and neoplastic tissues.13-14 In
our study, weak expression was seen in the cytoplasm of ductal epithelial
cells, and no staining was seen in normal parotid acini (Figure 1, C). Moderate-to-strong staining for TGF- was seen
in the cytoplasm of more than 90% of the tumor cells in 8 (67%) of 12 cases
(Figure 1, D). In another 4 cases,
weak-to-negative staining was seen. The immunohistochemical staining results
for TGF- are summarized in Table
2.
Epidermal growth factor receptor is normally expressed in nonneoplastic
adult tissues but appears to be overexpressed in carcinoma cells.15 In this study, EGFR expression was not detected in
normal parotid acini but was seen in ductal epithelial cells (Figure 1, 1 E). Moderate-to-strong staining for EGFR was seen in
the membrane and cytoplasm of more than 90% of the cancer cells (Figure 1, 1 F) in 11 (92%) of 12 cases (Table 2). Negative staining was detected
in 1 case (Table 2).
COMMENT
It has been established that overexpression of EGFR and/or TGF-
may represent an underlying mechanism of the development and progression of
human cancers. For example, expression of EGFR protein in breast carcinoma
is correlated with a poor prognosis and a poor response to hormonal therapy.16-17 Poor clinical outcome appears to
be linked to elevated EGFR and TGF- levels in patients with cancer.18-19 In patients with head and neck squamous
cell carcinoma, increased EGFR and TGF- levels are significantly correlated
with shortened disease-free survival.20
Human prostate and mammary glands are dependent on androgens and estrogens
for the maintenance of their growth and functional integrity. It is, therefore,
not surprising to find that the TGF-/EGFR autocrine growth pathway,
present in both prostatic and breast carcinomas, is also affected by these
hormones.21-22
The expression of AR has been shown in prostate, breast, sebaceous,
and sweat glands but not in salivary glands, gastrointestinal tract, thyroid,
pancreas, and adrenal gland.12 The mechanisms
underlying the aberrant expression of AR in SDC of the parotid glands currently
remain unknown.
Our previous study9 established that
SDCs frequently express AR (92%) and occasionally prostatic acid phosphatase
(58%) and prostatic-specific antigen (17%), indicative of a close immunophenotypic
homology between SDC and prostatic carcinoma. In the present study, we further
establish that a TGF-/EGFR autocrine pathway is present in SDCs, suggestive
of a similar mechanism of carcinogenesis between SDC and prostatic carcinoma.
Because of a small sample size (12 cases) in the present study, it is
impossible to establish a definitive link between the expression of AR and
TGF-/EGFR. Our study, however, provides the direction for future investigation
in which definitive roles of AR expression in the modulation of TGF-/EGFR
autocrine pathway can be analyzed. Unequivocal supportive evidence for the
roles of AR expression in the tumorigenesis of SDC is of paramount significance
because it may provide a basis for the use of alternative therapies, such
as antiandrogen therapy as used in prostatic carcinoma in patients with metastatic
SDC in whom current conventional therapeutic modalities fail.
In summary, we have shown that SDC frequently expresses AR (92%), TGF-
(67%), and EGFR (92%), suggestive of the presence of an AR-mediated TGF-/EGFR
autocrine pathway in these neoplasms. We propose that SDC may share a mechanism
of carcinogenesis similar to that of prostatic carcinoma.
AUTHOR INFORMATION
Accepted for publication February 7, 2001.
This study was supported by the Pathology Education and Research Foundation,
Department of Pathology, University of Pittsburgh Medical Center.
Corresponding author and reprints: E. Leon Barnes, MD, Department
of Pathology, University of Pittsburgh Medical Center, 200 Lothrop St, Pittsburgh,
PA 15213.
From the Department of Pathology, University of Arkansas for Medical
Sciences, Little Rock (Dr Fan); Department of Pathology, Veterans Affairs
Medical Center, Pittsburgh, Pa (Dr Melhem); Department of Otolaryngology,
Hacettepe University Medical Faculty, Ankara, Turkey (Dr Hosal); and Departments
of Otolaryngology (Dr Grandis) and Pathology (Dr Barnes), University of Pittsburgh
School of Medicine, Pittsburgh, Pa.
REFERENCES
| |
1. Dulbecco R. Topoinhibition and serum requirement of transformed and untransformed
cells. Nature. 1970;227:802-806.
FULL TEXT
| PUBMED
2. Kaplan PL, Anderson M, Ozanne B. Transforming growth factor production enables cells to grow in the
absence of serum: an autocrine system. Proc Natl Acad Sci U S A. 1982;79:485-489.
FREE FULL TEXT
3. Derynck R, Goeddel DV, Ullrich A, et al. Synthesis of messenger RNAs for transforming growth factor
and ß and the epidermal growth factor receptor by human tumors. Cancer Res. 1987;47:707-712.
FREE FULL TEXT
4. Sporn MB, Todaro GJ. Autocrine secretion and malignant transformation of cells. N Engl J Med. 1980;303:878-880.
ISI
| PUBMED
5. Rosenthal A, Lindquist PB, Bringman TS, Goeddel DV, Derynck R. Expression in rat fibroblasts of a human transforming growth factor-alpha
cDNA results in transformation. Cell. 1986;46:301-309.
FULL TEXT
|
ISI
| PUBMED
6. Culig Z, Hobisch A, Cronauer MV, et al. Regulation of prostatic growth and function by peptide growth factors. Prostate. 1996;28:392-405.
FULL TEXT
|
ISI
| PUBMED
7. Steiner MS. Review of peptide growth factors in benign prostatic hyperplasia and
urological malignancy. J Urol. 1995;153:1085-1096.
FULL TEXT
|
ISI
| PUBMED
8. Kapadia SB, Barnes EL. Expression of androgen receptor, gross cystic disease fluid protein,
and CD44 in salivary duct carcinoma. Mod Pathol. 1998;11:1033-1038.
ISI
| PUBMED
9. Fan CY, Wang J, Barnes EL. Expression of prostatic specific markers and androgen receptor in salivary
duct carcinoma: an immunohistochemical analysis of 13 cases and review of
literature. Am J Surg Pathol. 2000;24:579-586.
FULL TEXT
|
ISI
| PUBMED
10. Hsu SM, Raine L, Fanger H. A comparative study of the peroxidase-antiperoxidase method and an
avidin-biotin complex method for studying polypeptide hormones with radioimmunoassay
antibodies. Am J Clin Pathol. 1981;75:734-738.
ISI
| PUBMED
11. Iwamura M, Abrahamsson P, Benning CM, Cockett ATK, Sant'agnese PAD. Androgen receptor immunostaining and its tissue distribution in formalin-embedded
sections after microwave treatment. J Histochem Cytochem. 1994;42:783-788.
ABSTRACT
12. Ruizeveld de Winter JA, Trapman J, Vermey M, Mulder E, Zegers ND, van der Kwast TH. Androgen receptor expression in human tissues: an immunohistochemical
study. J Histochem Cytochem. 1991;39:927-936.
ABSTRACT
13. Coffey RJ, Derynck R, Wilcox JN, et al. Production and auto-induction of transforming growth factor-
in keratinocytes. Nature. 1987;328:817-820.
FULL TEXT
| PUBMED
14. Samsoondor J, Kobrin MS, Kudlow A. Alpha-transforming growth factor secreted by untransformed bovine anterior
pituitary cells in culture: purification from conditioned media. J Biol Chem. 1986;261:14408-14418.
FREE FULL TEXT
15. Grandis JR, Melhem MF, Barnes EL, Tweardy DJ. Quantitative immunohistochemical analysis of transforming growth factor-
and epidermal growth factor receptor in patients with squamous cell carcinoma
of the head and neck. Cancer. 1996;78:1284-1292.
FULL TEXT
|
ISI
| PUBMED
16. Klijn JG, Look MP, Portengen H, Alexieva-Figusch J, van Putten WL, Foekens JA. The prognostic value of epidermal growth factor receptor (EGF-R) in
primary breast cancer: results of a 10 year follow-up study. Breast Cancer Res Treat. 1994;29:73-83.
FULL TEXT
|
ISI
| PUBMED
17. Fox SB, Smith K, Hollyer J, Greenall M, Hastrich D, Harris AL. The epidermal growth factor receptor as a prognostic marker: results
of 370 patients and review of 3009 patients. Breast Cancer Res Treat. 1994;29:41-49.
FULL TEXT
|
ISI
| PUBMED
18. Veale D, Ashcroft T, Marsh C, Gibson GJ, Harris AL. Epidermal growth factor receptors in non-small cell lung cancer. Br J Cancer. 1987;55:513-516.
ISI
| PUBMED
19. Lager DJ, Slagel DD, Palechek PL. The expression of epidermal growth factor and transforming growth factor
alpha in renal cell carcinoma. Mod Pathol. 1994;7:544-548.
ISI
| PUBMED
20. Grandis JR, Melhem MF, Gooding WE, et al. Levels of TGF and EGFR protein in head and neck squamous cell
carcinoma and patient survival. J Natl Cancer Inst. 1998;90:824-832.
FREE FULL TEXT
21. Liu X, Wiley HS, Meikle AW. Androgens regulate proliferation of human prostate cancer cells in
culture by increasing transforming growth factor- (TGF-) and
epidermal growth factor (EGF)/TGF- receptor. J Clin Endocrinol Metab. 1993;77:1472-1478.
ABSTRACT
22. Lippman ME, Dickson RB, Bates S. Autocrine and paracrine growth regulation of human breast cancer. Breast Cancer Res. 1986;7:59-70.
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