Molecular Diagnosis in Pathology: The Bridge to the 21st Century
Moderators: Dr. Ricardo Lloyd and Dr. George Kontogeorgos
Section 2 -
Molecular Approaches to the Diagnosis of Bone Tumors
Gene P. Siegal, M.D., Ph.D. and Walter C. Bell, M.D
University of Alabama at Birmingham, USA
The classification of primary tumors of bone is complex, and as with all bone tumors requires
consideration of tumor location, level of aggressiveness by clinical and radiological characteristics,
and histology. The purpose of this presentation is to present a brief overview of the cytogenetic and
molecular genetic findings associated with a wide range of neoplasms free of the traditional detailed
exposition found in the primary literature. Some findings are characteristic of certain tumor types and
has already begun to contribute to the determination of proper classification, serve as a clinical
biomarker and have prognostic implications. The limited time allocated to this topic requires by
necessity a limited exposition to select tumor types . Because the majority of the literature is focused
on the malignant, small cell, blue, tumors of bone [and is therefore most familiar to the practicing
diagnostic pathologist] it is tempting to focus on these. However, we have arbitrarily elected to
purposely exclude those lesions and rather focus on chondroid lesions. As I example of the complexity of
the topic of molecular approaches to bone tumors, we direct interested readers to our about to be
published review article on p53 and cell cycle genes in osteosarcoma (Ternovoi et al, 2006).
Chondromas are common neoplasms and includes enchondroma, periosteal chondroma, and the rare
extraskeletal soft tissue chondroma (Fechner and Mills, 1993). No distinctive cytogenetic or molecular
findings distinguish among the various types of chondroma. Several studies have examined the karyotypic
changes observed in enchondroma. Bridge et al. (1992) evaluated 7 solitary enchondromas for cytogenetic
abnormalities. Five of the cases showed normal karyotypes. Clonal abnormalities were identified in two
of the cases. These included an isochrome of the short arm of chromosome 6 (p10) and t(12;15)(q13;q26)
in one case. These findings were of interest as similar changes have been described in chondrosarcoma.
Other authors have also described alterations in chromosome 6 and in the long arm of chromosome 12 in
enchondromas (Sawyer et al 1998; Buddingh et al. 2003) as well as in extraskeletal soft tissue chondromas
(Dal Cin et al, 1997 ; Shadan et al, 2000). More recently, 12q13-15 segment has been shown to be
nonrandomly involved in structural rearrangements in chondromas. The HMGA2 locus appears to be critical
(Dahlen et al, 2003). Comparative genomic hybridization has been applied in only rare cases. Ozaki and
associates studied 3 benign cartilaginous lesions, 2 of which were enchondromas. These tumors had small
numbers of chromosomal aberrations (gains and losses). Both of the gains occurred on 13q21 and losses
were observed on chromosomes 19 and 22q ( Ozaki et al, 2004). Interstingly, Indian Hedge Hog signalling
thought to be critical in normal cartilage differentiation and maturation appears to be absent in
enchondromas while parathyroid related protein [PTHrP] signalling is active but independent of IHH
signalling (Rozeman et al, 2005).
Ollier disease is a rare, nonhereditary, disorder characterized by multiple enchondromatosis in
children. A single study has examined the cytogenetic findings in a chondrosarcoma arising in Ollier
Disease identifying del(1)(p11p31.2) as the only chromosomal abnormality (Ozisik et al, 1998). No
detailed molecular or cytogenetic studies are yet reported for Maffucci syndrome, a syndrome similar to
Ollier disease, but in addition to enchondromatosis, the patients also develop numerous hemangiomas and
have a lower rate of development of chondrosarcoma. Neither Ollier's disease nor Maffucci syndrome is
thought to be caused by mutations of PTHR1 (Rozeman et al, 2004), an activating mutation in the
parathyroid hormone receptor type 1 gene previously reported in a subset patients with enchondromatosis.
That mutation is thought to result in upregulation of the Indian hedge Hog - PTHrP pathway (Hopyan et al,
The majority of osteochondromas arise spontaneously, but a familial form, hereditary multiple
exostoses syndrome (HME) exists. This is an autosomal dominant condition with incomplete penetrance in
woman. Presentation can range from involvement of a single bone to extensive involvement of almost every
bone in the body (Fechner and Mills, 1993). The molecular mechanisms of HME and solitary osteochondromas
have been extensively studied and a strong association with mutations in EXT genes, 1-3 has been
reported. In one large study of cytogenetic abnormalities in osteochondroma, Bridge et al. (1998)
evaluated 34 tumors from 22 patients with sporadic osteochondromas and 4 patients with HME. Clonal
changes were found in 10 of the cases. A deletion of 11p11.2-13 (corresponding to the EXT2 gene locus)
was identified in one case. Eight cases exhibited loss or rearrangement of 8q22-24.1. These included 7
solitary osteochondromas and one case of HME. At the molecular level, mutations in EXT1 and/or EXT2
have been identified in over 70% of HME cases with 49 different EXT1 mutations and 25 different EXT2
mutations identified (Wuyts and Van Hull, 2000). Additionally, decreased levels of the EXT1 and EXT2
proteins have been demonstrated by immunohistochemistry in chondrocytes from osteochondroma as compared
to normal control chondrocytes (Bernard et al, 2001). EXT1 and EXT2 are transmembrane glycoproteins
involved in the synthesis of heparin sulfate. Both genes have been cloned and are located on chromosomes
8q23-q24 and 11p11-p13 respectively (Wuyts et al, 1996; Ahn et al, 1995). A third gene, EXT3 which
localizes to chromosome 19p may also play a role in the development of osteochondroma.
The mechanism by which EXT mutations contribute to the formation of osteochondromas remains
uncertain. Interestingly, it has been demonstrated that EXT2 does not function independently of EXT1 in
glycosyltransferase activity and that a golgi localized EXT1/EXT2 hetero-oligomeric complex is formed
which has much greater glycosyltransferase activity than either protein alone. This relationship
suggests a mechanism by which mutation of either gene may result in loss of activity (McCormick et al,
2000). A proposed functional model has been suggested by Duncan et al (2001). Indian hedgehog (Ihh) and
parathyroid hormone-related peptide serve as signaling molecules to regulate chondrocyte proliferation
and hypertrophy. Ihh is produced by chondrocytes within the growth plate and binds to receptors on the
osteogenic cells. This binding upregulates PTHrP binds to proliferating chondrocytes, inhibiting
differentiation and apoptosis through induction of Bcl-2 production. Embryologic studies have
demonstrated a requirement for heparin sulfate in order for Ihh to associate with target cells (Lin et
al, 2000). It is proposed that the defective heparin sulfate production associated with EXT mutations
causes a disruption in this signaling pathway which could cause aberrant maturation and bone growth
within the proliferating cartilage.
Few studies have been performed regarding cytogenetic alterations in chondromyxoid fibroma. Sawyer et
al. (1998) demonstrated complex rearrangements involving chromosome 6 homologues resulting in an
inv(6)(p25q13)t(6;6)(q23;q13) in a single case. Halbert et al. (1998) identified a case of
chondromyxoid fibroma with unbalanced reciprocal translocations between the short arm of chromosome 3 and
the long arm of chromosome 6 with loss of multiple bands from chromosome 3 and rearrangements of several
bands (6q21, 6q22, 6q23) on chromosome 6. Interestingly, one of the bands lost in chromosome 3, 3p21, is
the locus for the PTHrP gene. Granter et al. (1998) examined 4 cases of chondromyxoid fibroma for
karyotypic abnormalities and found all four to contain rearrangements of chromosome 6 involving band
6q13. Two of the tumors exhibited the inv(6)(p25q13) inversion previously described by Sawyer et al
(1998). Such 6q13 rearrangements have not been described in other soft tissue tumors and may represent a
relatively specific chromosomal marker for chondromyxoid fibroma. Safar et al. (2000) also describe
chromosome 6 abnormalities in 2 cases of chondromyxoid fibroma. In their cases chromosome 6
translocations resulted in breakpoints at q25, distal to the q13 breakpoint in the previously described
pericentric inversion. Work from our laboratory has provided preliminary evidence that surface CMF
lesions have a different cytogenetic pattern than that recognized with conventional intramedullary forms.
Although the morophologic features of CMF mimic that of normal chondrogenesis, expression of signaling
molecules appears different. Specifically, N-cadherin, PTHLH and PTHR1 have been shown to be upregulated
in normal cells as compared to those derived from CMF while increased expression of cyclin D!, P16 and
BCL2 were observed in CMF cells (Romeo et al, 2005).
Few chromosomal studies have been performed for chondroblastoma with no specific cytogenetic
findings. VanZelderen-Bhola et al (1998) report a ring chromosome 4 in approximately 1/3 of cells from a
single case of chondroblastoma. Aigner et al. (1999) analysed the extracellular matrix in a series of
chondroblastoma cases and failed to demonstrate type II collagen, the dominate matrix component of
cartilage matrix. Instead, the matrix was predominately composed of type I collagen, the prominent
component of osteoid. This has subsequently been further confirmed (Schorle et al., 2002). The authors
suggest that chondroblastoma should be classified as a bone forming rather than cartilage-forming
neoplasm. Dutch investigators (Romeo et al., 2004) have now shown that mesenchymal associated active
growth plate signaling molecules including FGF-2 and its receptors FGFR-1 & 3 along with Ihh/PTHrP
were expressed in the majority of cases. Most recently, using a combination of SKY and FISH, diploid or
near-diploid karyotypes were recognized in virtually all these lesions which on further analysis were
noted to have recurrent breakpoints at 2q35, 3q21-23 and 18q21 (Sjogren et al, 2004).
The clinical distinction between chondroma and low grade chondrosarcoma may be difficult. Sawyer et
al (1998) suggest that chromosomal alterations in the region of 6q13-21 may be associated with locally
aggressive behavior in cartilaginous tumors although t(6;15)(q13;q11) is reported for an enchondroma in
this study. Amling et al (1998) suggest that regulators of chondrocyte differentiation, parathyroid
hormone-related peptide (PTHrP) and Bcl-2, may aid in differentiation of benign and malignant
cartilaginous tumors. They compared expression of these two markers by immunohistochemistry in 9
enchondromas and 14 chondrosarcomas of varying grade with increased expression of both markers in
chondrosarcoma as compared with the enchondromas. Ploidy analysis has also been suggested as a useful
adjunct in distinguishing benign from malignant cartilaginous neoplasms (Kusuzaki et al, 1999).
Cytogenetics of Conventional chondrosarcoma
There have been numerous series reporting the cytogenetic alterations in chondrosarcoma (Orndal et
al., 1993; Tallini et al., 2002; Swarts et al., 1997; Gunawan et al., 2000; Bovee et al., 2001). In a
recent large series examining 59 conventional chondrosarcomas, Mandahl et al. (2002) identify a number
of chromosomal regions which were deleted in 10 or more of the cases: 1p36, 1p13-p22, 4, 5q13-q31,
6q22-qter, 7p13-pter, 9p22-pter, 10p, 10q24-qter, 11p13-pter, 11q25, 12q15-qter, 13q21-qter,
14q24-qter, 18p, 18q22-qter, 19, 20pter-q11, 21q, and 22q13. Of these, loss of 13q served as an
independent prognostic factor for metastasis regardless of tumor grade or size.
Oncogenes of Conventional chondrosarcoma
Although no clearly reproducible patterns have emerged, increased expression of a number of oncogenes
has been described in chondrosarcoma. Wrba et al. (1989) evaluated the expression of erb-B2 by
immunohistochemistry in 23 cases of chondrosarcoma and found staining in 18 of the cases with no staining
in normal cartilage controls. Castresana et al. (1992) found amplification of c-myc in two of nine
cases examined. Immunoreactivity for c-MET has been describe in 54% of chondrosarcomas in one series,
although there was no correlation with grade and even higher percentages of staining were observed in
benign chondroid neoplasms (Naka et al, 1997). A single study used an in-situ hybridization technique
to evaluate the expression of c-fos in chondrosarcoma (Weisstein et al, 2001). Moderate expression of
c-fos was identified in 3 of 6 cases and high expression levels were observed in one case. Other
authors have reported the absence of c-fos expression in chondrosarcomas (Franchii et al, 1998; Pompetti
et al, 1996). Proto-oncogenes which have been evaluated in chondrosarcoma and have not been found to be
overexpressed include c-jun, c-myb, H-ras, K-ras, N-ras, and c-fms (Franchi et al., 1998; Pompetti et
al., 1996; Castresana et al., 1992). Minichromosome maintenance protein (MCM6) has recently been shown
to be up-regulated in low-grade chondrosarcoma as compared to enchondromas (Helfenstein et al, 2004).
Tumor Suppressor Genes of Conventional chondrosarcoma
Wadayama et al. (1993) evaluated chondrosarcomas for p53 alterations by immunohistochemical staining
for p53 and report staining in 5 of the 20 cases examined. Staining was identified in high grade tumors
but not in low grade tumors. Similarly, Simms et al. (1995) noted increased immunoreactivity for p53 in
the high grade and dedifferentiated components of 8 dedifferentiated chondrosarcomas while lower grade
chondrosarcoma components of 6 of the tumors showed no immunoreactivity. Other authors have also
described increased expression of p53 or alteration of p53 associated with high grade and
dedifferentiated tumors (Grote et al. 2000; Oshiro et al. 1998; Terek et al. 1998). Raskind et al.
(1996) describe frequent loss of heterozygosity in chondrosarcoma on chromosome 10q suggesting a possible
tumor supressor gene in this region. The role of the p16/pRB/cdk4 pathway has also been evaluated in a
series of 8 chondrosarcomas by Western Blot analysis of the proteins (Asp et al., 2001). They saw loss
of expression of p16 in one case, and this case was shown to have homozygous deletion of CKDN2, the p16
Other Signaling Proteins
Bovee et al. (2000) evaluated the expression of PTHrP and bcl-2 in both central and peripheral
chondrosarcomas. They found increased expression of these markers by immunohistochemistry as an early
event in peripheral chondrosarcomas (occurring in low grade chondrosarcomas and not in osteochondromas)
and a late event in central chondrosarcomas (expression largely confined to high grade tumors). Nishida
et al. (2002) demonstrated expression of peroxidome proliferator-activated receptor-gamma by IHC in
67.9% of 28 human chondrosarcomas evaluated. Using a chondrosarcoma cell line, they were able to block
proliferation and induce apoptosis using a specific ligand to this receptor suggesting that this receptor
may play an important role in cellular proliferation in chondrosarcoma. In a similar study, Miyaji et a.
(2003) have show that an anti-PTHrP monoclonal antibody induced apoptosis in a chondrosarcoma cell line.
Extraskeletal Myxoid Chondrosarcoma
EMC stands alone among chondrosarcoma variants as having distinctive cytogenetic and molecular
alterations. A t(9;22)(q22;q12) translocation has long been recognized and is identified in
approximately 75% of cases (Turc-Carel et al., 1988; Orndal C et al., 1991; Hirabayashi et al., 1995;
Stenman et al., 1995; Sciot et al., 1995). This translocation results in fusion of the 5' portion of the
EWS gene to the TEC (also known as NOR1 and CHN) gene which encodes an orphan nuclear receptor (Labelle
et al., 1995; Kleinfinger et al., 1996; Brody et al., 1997; Panagopoulos et al., 2002 ) . The resulting
fusion protein acts as a transcription factor (Labelle et al., 1999; Maltais et al., 2002; ) and also is
involved in regulation of mRNA splicing (Ohkura et al., 2002). Two additional related translocations
have also been described in EMC. A t(9;17)(q22;q11) translocation is seen in approximately 15% of cases
and results in a fusion of the amino portion of the TAF2N (TAF15, a gene closely related to EWS) gene to
TEC (Sjogren et al., 1999, Bjerkehagen et al., 1999; Attwooll et al., 1999; Panagopoulos et al., 2002).
The third variant, t(9;15)(q22;q21) results in a fusion of TCF12 (basic helix-loop-helix transcription
factor) to TEC (Sjogren et al., 2000).
Sjogren et al. (2003) evaluated ten cases of EMCs and identified clonal chromosomal abnormalities in
9 of the cases. Characteristic fusion proteins, including 5 cases with EWS-TEC, 4 cases with TAF2N-TEC,
and 1 case with TCF12-TEC, were identified for all cases. Additionally, the authors performed cDNA
microarray analysis for two cases (compared to myxoid liposarcoma) and found the most differentially
expressed gene for both EMCs to be CHI3L1, which encodes a glycoprotein involved in extracellular matrix
degradation, suggesting a possible role in tumor invasion. Another recent study demonstrates the
function of Six3, a homeotic protein as a cofactor in transcriptional activation of TEC alone and a
co-repressor of transcriptional activity of the EWS-TEC fusion protein (Laflamme et al., 2003). The
authors also demonstrated co-expression of the EWS-TEC fusion protein and Six3 in four cases of ECM.
Interestingly, it has recently been suggested (Aigner et al., 2004) that extraskeletal lesions do not
show a chroncytic phenotype but rather primitive pleuipotential mesenchymal cells. Lastly, a team of
North American investigators (Subramanian et al., 2004) have shown that neuromedin B [NMB] is a highly
expressed gene in all cases examuned using cDNA microarray technology.
Clear Cell Chondrosarcoma
Due to the rarity of these neoplasms, few molecular studies have been performed. Kleist et al.
(2002) demonstrated allelic loss at 9p22 and 18q21 and methylation of the p16 gene on chromosome 9p in a
case of clear cell chondrosarcoma of the larynx. Park and colleagues from Korea, Jkapan and the Mayo
clinic found p53 genetic alterations to be a rare event in clear cell chondrosarcomas in the face of a
significant fraction of cases demonstrating overexpression of the molecule (Park et al, 2001a).
Similarly, only a low incidence [2/38] of genetic alterations in the cyclin-dependent kinase inhibitor
p16CDKN2a tumor suppressor gene was identified in these same lesions (Park et al, 2001b).
Cytogenetic studies have revealed no characteristic karyotypic abnormalities for mesenchymal
chondrosarcoma (Sainati et al., 1993; Dobin et al., 1995; Szymanska et al., 1996). Naumann et al.
(2002) have described two cases of mesenchymal chondrosarcoma, one skeletal and one extraskeletal, with
der(13;21)(q10;q10) suggesting that translocations in this region may be significant in the development
of these tumors. Park et al. (2000) evaluated 33 cases of mesenchymal chondrosarcoma for p53 expression
and mutation. They report increased expression of p53 in 61.3% of cases, but no p53 gene mutations in
exons 5-9. Wehrli et al. (2003) evaluated the expression of Sox9, a transcription factor which plays a
role in the differentiation of mesenchymal cells into chondrocytes, in mesenchymal chondrosarcoma and
other small blue cell tumors. They found expression of Sox9 by immunohistochemistry in 21 of 22 cases of
mesenchymal chondrosarcoma, and no expression in any of the other tumors evaluated, which included
Ewing's sarcoma/PNET, small cell osteosarcoma, and extraskeletal myxoid chondrosarcoma. This supports
the recapitulation of early chondroid differentiation in the small blue cell component of these tumors
and suggests that Sox9 may prove to be a useful diagnostic marker.
- Ahn J, Ludecke H, Lindow S, Horton WA, Lee B, Wagner MJ, Horsthemke B, Wells DE. Cloning of the putative tumour suppressor gene for hereditary multiple exostoses (EXT1). Nature Genetic. 11:137-143, 1995.
- Aigner T, Loos S, Inwards C, Perris R, Perissinotto D, Unni KK, Kirchner T. Chondroblastoma is an osteoid-forming, but not cartilage-forming neoplasm. J Pathol. 189:463-9, 1999.
- Aigner T, Oliveria, AM, Nascimento, AG: Extraskeletal myxoid chondrosarcomas do not show a chondrocytic phenotype. Modern Pathol 17:214-221, 2004.
- Amling M, Posl M, Hentz MW, Priemel M, Delling G. PTHrP an Bcl-2: essential regulatory molecules in chondrocyte differentiation and chondrogenic tumors. Verhandlungen Deutsch Gesells Patho. 82:160-9, 1998.
- Asp J, Inerot S, Block JA, Lindahl A. Alterations in the regulatory pathway involving p16, pRb, and cdk4 in human chondrosarcoma. J Ortho Res. 19:149-54, 2001.
- Attwooll C, Tariq M, Harris M, Coyne JD, Telford N, Varley JM. Identification of a novel fusion gene involving hTAFII68 and CHN from a t(9;17)(q22q11.2) translocation in an extraskeletal myxoid chondrosarcoma. Oncogene. 18:7599-601, 1999.
- Bernard MA, Hall CE, Hogue DA, Cole WG, Scott A, et al. Diminished levels of the putative tumor suppressor proteins EXT1 and EXT2 in exostoses chondrocytes. Cell Mot Cytoskel. 48:149-62, 2001.
- Bjerkenhagen B, Dietrich C, Reed W, Micci F, Saeter G, Berner A, Nesland JM, Heim S. Extraskeletal myxoid chondrosarcoma:multimodal diagnosis and identification of a new cytogenetic subgroup characterized by t(9;17)(q22;q11). Virchow Arch. 435:524-30, 1999.
- Bovee JV. Sciot R. Cin PD. Debiec-Rychter M. van Zelderen-Bhola SL. Cornelisse CJ. Hogendoorn PC. Chromosome 9 alterations and trisomy 22 in central chondrosarcoma: a cytogenetic and DNA flow cytometric analysis of chondrosarcoma subtypes. Diagnost Mol Pathol. 10(4):228-35, 2001.
- Bovee JV, van den Broek LJ, Cleton-Jansen AM, Hogendoorn PC. Up-regulation of PTHrP and Bcl-2 expression characterizes the progression of osteochondroma towards peripheral chondrosarcomas and is a late event in central chondrosarcoma. Lab Invest. 80:1925-34, 2000.
- Bridge JA, Nelson M, Orndal C, Bhatia P, Neff JR. Clonal karyotypic abnormalities of the hereditary multiple exostoses chromosomal loci 8q24.1 (EXT1) and 11p11-12 (EXT2) in patients with sporadic and hereditary osteochondroma. Cancer. 82:1657-63, 1998.
- Bridge JA, Persons DL, Neff JR, Bhatia P. Clonal karyotypic aberrations in enchondroma. Cancer Detect Prev. 16(4):215-9, 1992.
- Brody RI, Ueda T, Hamelin A, Jhanwar SC, Bridge JA, Healey JH, Huvos AG, Gerald WL, Ladanyi M. Molecular analysis of the fusion of EWS to an orphan nuclear receptor gene in extraskeletal myxoid chondrosarcoma. Am J Pathol. 150:1049-58, 1997.
- Buddingh EP, Naumann S, Nelson M, Neffa JR, Birch N, Bridge JA. Cytogenetic findings in benign cartilaginous neoplasms. Cancer Gen Cytogenet. 141(2):164-8, 2003.
- Castresana JS, Barrios C, Gomez L, Kreicbergs A. Amplification of the c-myc proto-oncogene in human chondrosarcoma. Diagnost Mol Pathol. 1:235-8, 1992.
- Dal Cin P, Qi H, Sciot R, Van den Berghe H. Involvement of chromosomes 6 and 11 in a soft tissue chondroma. Cancer Genetic Cytogenet. 93(2):177-8, 1997.
- Dahlen A, Mertens F, Rydholm A, Brosjo O, Wejde J, Mandahl N, Panagopoulos I. Fusion, disruption, and expression of HMGA2 in bone and soft tissue chondromas. Modern Pathol 16:1132-40, 2003.
- Dobin SM, Donner LR, Speights VO. Mesenchymal chondrosarcoma. A cytogenetic, immunohistochemical and ultrastructural study. Cancer Genetic Cytogenet. 83: 56-60, 1995.
- Duncan G, McCormick C, Tufaro F. The link between heparin sulfate and hereditary bone disease: finding a function for the EXT family of putative tumor suppressor proteins. J Clin Invest 108:511-6, 2001.
- Fechner RE, Mills SE. Cartilaginous Lesions pp 79-128 in: Atlas of Tumor Pathology, Tumors of the Bones and Joints. Armed Forces Institute of Pathology. 1993.
- Franchi A, Calzolari A, Zampi G. Immunohistochemical detection of c-fos and c-jun expression in osseous an cartilaginous tumours of the skeleton. Virchow Arch. 432:515-9, 1998.
- Granter SR, Renshaw AA, Kozadewich HP, Fletcher JA. The pericentromeric inversion, inv (6)(p25q13), is a novel diagnostic marker in chondromyxoid fibroma. Modern Pathol. 11:1071-4, 1998.
- Grote HJ, Schneider-Stock R, Neumann W, Roessner A. Mutation of p53 with loss of heterozygosity in the osteosarcomatous component of a dedifferentiated chondrosarcoma. Virchow Arch 436:494-7, 2000.
- Gunawan B. Weber M. Bergmann F. Wildberger J. Niethard FU. Fuzesi L. Clonal chromosome abnormalities in enchondromas and chondrosarcomas. Cancer GeneticCytogenetic. 120(2):127-30, 2000.
- Gunawan B, Weber M, Bergmann F, Wildberger J, Fuzesi L. Solitary enchondroma with Clonal chromosomal abnormalities. Cancer Genetic Cytogenetic. 104(2):161-4, 1998.
- Halbert AR, Harrison WR, Hicks MJ, Davino N, Cooley LD. Cytogenetic analysis of a scapular chondromyxoid fibroma. Cancer Genetic Cytogenetic. 104:52-6, 1998.
- Helfenstein A, Frahm SO, Krams M, Drescher W, Parwaresch R, Hassenpflug J. Minichromosome maintenance protein (MCM6) in low-grade chondrosarcoma: distinction from enchondroma and identification of progressive tumors. Am J Clin Pathol. 122:912-8. 2004.
- Hirabayashi Y, Ishida T, Yoshida MA, Kojima T, Ebihara Y, Machinami R, Ikeuchi T. Translocation (9;22)(q22;q12). A recurrent chromosome abnormality in extraskeletal myxoid chondrosarcoma. Cancer Genetic Cytogenetic. 8:33-7, 1995.
- Hopyan S, Gokgoz N, Poon R, Gensure RC, Yu C, Cole WG, Bell RS, Juppner H,Andrulis IL, Wunder JS, Alman BA. A mutant PTH/PTHrP type I receptor in enchondromatosis. Nat Genet. 30(3):306-10, 2002.
- Kleinfinger P, Labelle Y, Melot T, Thomas G, Delattre O, Aurias A. Localization of TEC to 9q22.3-q31 by fluorescence in situ hybridization. Annal Gene. 39:233-5, 1996.
- Kleist B, Poetsch M, Lang C, Bankau A, Lorenz G, Suess-Fridrich K, Jundt G, Wolf E. Clear cell chondrosarcoma of the larynz: a case report of a rare histologic variant in an uncommon location. Am J Surg Pathol. 26:386-92, 2002.
- Kusuzaki K, Murata H, Takeshita H, Hirata M, Hashiguchi S, Tsuji Y, Nakamura S, Ashihara T, Hirasawa Y. Modern Pathol. 12(9):863-72, 1999.
- Labelle Y, Zucman J, Stenman G, Kindblom LG, Knight J, Turc-Carel C, et al. Oncogenic conversion of a novel orphan nuclear receptor by chromosome translocation. Human Mol Genet. 4:2219-26, 1995.
- Labelle Y, Bussieres J, Courjal F, Goldring MB. The EWS/TEC fusion protein encoded by the t(9;22) chromosomal translocation in human chondrosarcomas is a highly potent transcriptional activator. Oncogene. 18: 3303-8, 1999.
- Laflamme C, Filion C, Bridge JA, Ladanyi M, Goldring MB, Labelle Y. The homeotic protein Six3 is a coactivator of the nuclear receptor NOR-1 and a corepressor of the fusion protein EWS/NOR-1 in human extraskeletal myxoid chondrosarcoma. Cancer Res. 63:449-54, 2003.
- Maltais A, Filion C, Labelle Y. The AF2 domain of the orphan nuclear receptor TEC is essential for the transcriptional activity of the oncogenic fusion protein EWS/TEC. Cancer Let. 183:87-94, 2002.
- McCormick C, Duncan G, Goutsos T, Tufaro F. The putative tumor suppressors EXT1 and EXT2 form a stable complex that accumulates in the Golgi apparatus and catalyzes the synthesis of heparin sulfate. Proc Natl Acad Sci USA. 97: 668-73; 2000.
- Meis-Kindblom JM, Bergh P, Gunterberg B, Kindblom L-G. Extraskeletal myxoid chondrosarcoma: A reappraisal of its morphologic spectrum and prognostic factors based on 117 cases. Am J Surg Pathol. 23:636-650, 1999.
- Miyaji T, Nakase T, Onuma E, Sato K, Myoui A, Tomita T, Joyama S, Ariga K, Hashimoto J, Ueda T, Yoshikawa H. Monoclonal antibody to parathyroid horomone-related protein induces differentiation and apoptosis of chondrosarcoma cells. Cancer Let. 199:147-55, 2003.
- Naka T, Iwamoto Y, Shinohara N, Ushijima M, Chuman H, Tsuneyoshi M. Expression of c-met proto-oncogene product (c-MET) in benign and malignant bone tumors. Modern Pathol. 10:832-8, 1997.
- Naumann S, Krallman PA, Unni KK, Fidler ME, Neff JR, Bridge JA. Translocation der(13;21)(q10;q10) in skeletal and extraskeletal mesenchymal chondrosarcoma. Modern Pathol. 15:572-6, 2002.
- Nishida K, Furumatsu T, Takada I, Kawai A, Yoshida A, Kunisada T, Inoue H. Inhibition of human chondrosarcoma cell growth via apoptosis by peroxisome proliferator-activated receptor-gamma. Br J Cancer. 86: 1303-9, 2002.
- Ohkura N, Yaguchi H, Tsukada T, Yamaguchi K. The EWS/NOR1 fusion gene product gains a novel activity affection pre-mRNA splicing. J Bio Chem. 277:535-43, 2002.
- Orndal C, Carlen B, Akerman M, Willen H, Mandahl N, Heim S, Rydholm A, Mitelman F. Chromosomal abnormality t(9;22)(q22;q12) in an extraskeletal myxoid chondrosarcoma characterized by fine needle aspiration cytology, electron microscopy, immunohistochemistry and DNA flow cytometry. Cytopathol. 2:261-70, 1991.
- Orndal C, Mandahl N, Rydholm A, Willen H, Brosjo O, Mitelman F. Chromosome aberrations and cytogenetic intratumor heterogeneity in chondrosarcomas. J Cancer Res Clin Oncol. 120:51-6, 1993.
- Oshiro Y, Chaturvedi V, Hayden D, Nazeer T, Johnson M, Johnston DA, Ordonez NG, Ayala AG, Czerniak B. Altered p53 is associated with aggressive behavior of chondrosarcoma: a long term follow-up study. Cancer. 83:2324-34, 1998.
- Ozaki T, Wai D, Schafer KL, Lindner N, Bocker W, Winkelmann W, Dockhorn-Dworniczak B, Poremba C. Comparative genomic hybridization in cartilaginous tumors. Anticancer Res. 24(3a):1721-5, 2004 .
- Ozisik YY, Meloni AM, Spanier SS, Bush CH, Kingsley KL, Sandberg AA. Deletion 1p in a low-grade chondrosarcoma in a patient with Ollier disease. Cancer Genetic Cytogenetic. 105:128-33, 1998.
- Panagopoulos I, Mertens F, Isaksson M, Domanski HA et al. Molecular genetic characterization of the EWS/CHN and RBP56/CHN fusion genes in extraskeletal myxoid chondrosarcoma. Gene Chrom Cancer. 35: 340-352, 2002.
- Park YK , Cho CH, Chi SG, Han CS, Ushigome S, Unni KK. Low incidence of genetic alterations of the p16CDKN2a in clear cell chondrosarcoma. Int J Oncol. 19(4):749-53, 2001.
- Park YK, Park HR, Chi SG, Kim CJ, Sohn KR, Koh JS, Kim CW, Yang WI, Ro JY, Ahn KW, Joo M, Kim YW, Lee J, Yang MH, Unni KK. Overexpression of p53 and rare genetic mutation in mesenchymal chondrosarcoma. Oncol Rep. 7:1041-7, 2000.
- Park YK , Park HR, Chi SG, Ushigome S, Unni KK. Overexpression of p53 and absent genetic mutation in clear cell chondrosarcoma. Int J Oncol. 19(2):353-7, 2001.
- Pompetti F, Rizzo P, Simon RM, Freidlin B, Mew DJ, Pass HI, Picci P, Levine AS, Carbone M. Oncogene alterations in primary, recurrent, and metastatic human bone tumors. J Cell Biochem. 63:37-50, 1996.
- Raskind WH, Conrad EU, Matsushita M. Frequent loss of heterozygosity for markers on chromosome arm 10q in chondrosarcomas. Gene Chrom Cancer. 16:138-43, 1996.
- Romeo S, Bovee JV, Jadnanansing NA, Taminiau AH, Hogendoorn PC. Expression of cartilage growth plate signalling molecules in chondroblastoma. J Pathol. 202:113-20 2004.
- Romeo S, Bovee JV, Grogan SP, Taminiau AH, Eilers PH, Cleton-Jansen AM, Mainil-Varlet P, Hogendoorn PC. Chondromyxoid fibroma resembles in vitro chondrogenesis, but differs in expression of signalling molecules. J Pathol. 206(2):135-42, 2005.
- Rozeman LB, Hameetman L, Cleton-Jansen AM, Taminiau AH, Hogendoorn PC, Bovee JV. Absence of IHH and retention of PTHrP signalling in enchondromas and central chondrosarcomas. J Pathol. 205(4):476-82, 2005.
- Rozeman LB, Sangiorgi L, Briaire-de Bruijn IH, Mainil-Varlet P, Bertoni F, Cleton-Jansen AM, Hogendoorn PC, Bovee JV. Enchondromatosis (Ollier disease, Maffucci syndrome) is not caused by the PTHR1 mutation p.R150C. Hum Mutat. 24(6):466-73, 2004.
- Safar A, Nelson M, Neff JR, Maale GE, Bayani J, Squire J, Bridge JA. Recurrent anomalies of 6q25 in chondromyxoid fibroma. Human Patholy. 31:306-11, 2000.
- Sainati L, Scapinello A, Montaldi A, Bolcato S, Ninfo V, Carli M, Basso G. A mesenchymal chondrosarcoma of a child with the reciprocal translocation (11;22)(q24;q12). Cancer Gen Cytogene. 71:144-6, 1993.
- Schorle CM, Inwards C, Unni KK, Kirchner T, Aigner T. Characterisation and differentiation of chondroblastomas and chondromyxoidfibromas - presence and expression of collagen types I and II Z Orthop Ihre Grenzgeb. 140:208-13, 2002.
- Sawyer JR, Swanson CM, Lukacs JL, Nicholas RW, North PE, Thomas JR. Evidence of an association between 6q13-21 chromosome aberrations and locally aggressive behavior in patients with cartilage tumors. Cancer. 82:474-83, 1998.
- Sciot R, Dal Cin P, Gletcher C, Samson I, Smith M, De Vos R, Van Damme B, Van den Berghe H. t(9;22)(q22-31;q11-12) is a consistent marker of extraskeletal myxoid chondrosarcoma: evaluation of three cases. Modern Patholy. 8:765-8, 1995.
- Shadan FF, Mascarello JT, Newbury RO, Dennis T, Spallone P, Stock AD. Supernumerary ring chromosomes derived from the long arm of chromosome 12 as the primary cytogenetic anomaly in a rare soft tissue chondroma. Cancer Genetic Cytogene. 118 (2):144-7, 2000.
- Simms WW, Ordonez NG, Johnston D, Ayala AG, Czerniak B. p53 expression in dedifferentiated chondrosarcoma. Cancer. 76:223-7, 1995.
- Sjogren H, Meis-Kindblom J, Kindblom LG, Aman P, Stenman G. Fusion of the EWS-related gene TAF2N to TEC in extraskeletal myxoid chondrosarcoma. Cancer Research 59:5064-7, 1999.
- Sjogren H, Meis-Kindblom JM, Orndal C, Bergh P, Ptaszynski K, Aman P, Kindblom LG, Stenman G. Studies on the molecular pathogenesis of extraskeletal myxoid chondrosarcoma - cytogenetic, molecular genetic, and cDNA microarray analysis. Am J Pathol. 162:781-792, 2003.
- Sjogren H, Wedell B, Meis-Kindblom JM, Kindblom LG, Stenman G, Kindblom JM. Fusion of the NH2-terminal domain of the basic helix-loop-helix protein TCF12 to TEC in extraskeletal myxoid chondrosarcoma with translocation t(9;15)(q22;q21). Cancer Res. 60:6832-5, 2000.
- Stenman G, Andersson H, Mandahl N, Meis-Kindblom JM, Kindblom LG. Translocation t(9;22)(q22;q12) is a primary cytogenetic abnormality in extraskeletal myxoid chondrosarcoma. International Journal of Cancer. 62:398-402, 1995.
- Subramanian S, West RB, Zhu S, Nielsen TO, Dry SM, Goldblum JR, Patel R, Rubin BP, Brown P, van de Rijn M Extraskeletal Myxoid Chondrosarcoma: Gene Discovery using cDNA Microarrays. Modern Pathol. 17:19A, 2004
- Swarts SJ. Neff JR. Nelson M. Johansson S. Bridge JA. Chromosomal abnormalities in low grade chondrosarcoma and a review of the literature. Cancer Genetic Cytogene. 98(2):126-30, 1997.
- Szymanska J, Tarkkanen M, Wiklund T, Virolainen M, Blomqvist C, Asko-Seljavaara S, Tukianine E, Elomaa I, Knuutila S. Cytogenetic study of extraskeletal mesenchymal chondrosarcoma. A case report. Cancer Genetic Cytogenes. 86:170-3, 1996.
- Tallini G, Dorfman H, Brys P, Dal Cin P, De Wever I, Fletcher CD, Jonson K, Mandahl N. Mertens F. Mitelman F. Rosai J. Rydholm A. Samson I. Sciot R. Van den Berghe H. Vanni R. Willen H. Correlation between clinicopathological features and karyotype in 100 cartilaginous and chordoid tumours. A report from the Chromosomes and Morphology (CHAMP) Collaborative Study Group. J Pathol. 196:194-203, 2002.
- Ternovoi, V.V., Curiel, D.T., Smith, B.F., and Siegal, G.P.: Adenovirus-mediated p53 tumor suppressor gene therapy of osteosarcoma. Laboratory Investigation 87:In Press, 2006.