Introduction
an endogenous (intrinsic) hypoxia marker in several models. PMID: 17172824, PMID: 16513206
a renal cell carcinoma (RCC)-specific tumor
protein.
PMID: 17146628
an interesting target for anticancer drug
development.
PMID: 16996620
a transmembrane protein whose expression is
strongly induced by hypoxia in a broad spectrum of human tumours.
PMID: 16278664
a stable marker of current or previous
chronic hypoxia but influenced by nonhypoxic stimuli.
PMID: 15752902
a membrane-associated carbonic anhydrase
(CA), strongly induced by hypoxia. CAIX is overexpressed in a
variety of tumor types and associated with increased metastasis
and poor prognosis.
PMID: 15342400
one of the most inducible and most uniformly
induced genes and because of its stability and membrane location
provides a reliable histochemical marker of hypoxia.
PMID: 14712082
regulated via hypoxia-inducible factor 1, is
a useful intrinsic marker of tumor hypoxia.
PMID: 14654550
Tumour-associated protein carbonic anhydrase
IX (CA IX) has two major forms. One is a cell-associated,
transmembrane protein seen on Western blots as a twin band of
54/58 kDa, expressed in gastric mucosa and in several types of
cancer. The other is a soluble protein s-CA IX of 50/54 kDa,
which is released into the culture medium or into the body
fluids, most likely by proteolytic cleavage of the extracellular
part from transmembrane and intracellular sequences.
PMID: 12966427
a
novel surrogate marker of tumor hypoxia, is associated with a
poor prognosis in non-small-cell lung cancer.
PMID: 12560438
an integral membrane protein and a member of
the alpha class of carbonic anhydrases that includes the human
and animal enzymes.
PMID: 11676494
a transmembrane enzyme with an extracellular
active site, is involved in the reversible metabolism of the
carbon dioxide to carbonic acid.
PMID: 11691824
Normal Expression
Normal human brain tissue shows only slight
or no expression of CA IX.
PMID: 16428489
a hypoxia-inducible enzyme, which is
expressed in the human and rodent gastrointestinal tract and
overexpressed in several different tumors.
PMID: 16245156
Expression of CA IX is normally restricted to
the mucosa of alimentary tract, but on the other hand, it takes
place in a high percentage of human cancers derived from tissues
which are normally CA IX-negative.
PMID: 15809767
Immunohistochemical (IHC) analysis showed
strong staining in the gastric mucosa. Moderate reactions were
seen in the colon enterocytes and pancreatic acini. The
expression pattern of CA IX was similar in certain human and
rodent tissues, although some differences existed, especially in
the gut epithelium.
PMID: 15385577
CA IX was highly expressed in the normal
gastric mucosa and remained positive in many gastric tumors.
PMID: 12854129
expressed in the basolateral plasma membrane
of normal biliary epithelial cells, but not in hepatocytes.
PMID: 11690711
both CA IX and XII are unevenly expressed in
the ductal and acinar compartments of the human pancreas.
PMID: 11083462
expressed in normal alimentary tract in a
tissue-specific manner.
PMID: 11771176
Specific staining for CA XII was present in
the basolateral plasma membrane of the epithelial cells in the
efferent ducts, predominantly in the non-ciliated cells.
PMID: 11420383
Abnormal Expression
a cell surface tumor-associated antigen
expressed by most clear cell renal cell carcinomas (RCCs).
PMID: 17095063
highly overexpressed in many types of cancer.
Its expression, which is regulated by the HIF-1 transcription
factor, is strongly induced by hypoxia and correlates with a
poor response to classical chemo- and radiotherapies.
PMID: 16996620
pre-dominantly expressed in tumors with poor
prognosis and its transcription and activity are induced by
hypoxia.
PMID: 16964400
is a membrane isoenzyme, the overexpression
of which is associated with clear cell carcinoma of the kidney.
Its overexpression is restricted mainly to cancer, as it is
absent in corresponding normal tissues making it a potential
cancer biomarker.
PMID: 16310354
can be induced by hypoxia in vitro and shows
an immunohistochemical expression pattern that is predominantly
found in perinecrotic tumor areas and correlates with exogenous
markers of hypoxia, such as pimonidazole.
PMID: 16243791
Carbonic anhydrase IX expression is observed
in both ductal epithelial and cancer cells of the pancreas.
PMID: 14535878
CA IX was detected by IHC in 12/26 (46%)
malignant tissues, 4/36 (11%) benign lesions, but not in 10
normal breasts.
PMID: 12115877
Expression Alteration
acidosis increases the CA IX expression via a
hypoxia-independent mechanism that operates through modulation
of the basic CA9 transcriptional machinery.
PMID: 16964400
CA IX carbonic anhydrase is a
hypoxia-inducible tumor-associated antigen which is
overexpressed in dense HeLa cells.
PMID: 12937836
Function
comparison of CAIX and pimonidazole will
allow for the detection of reoxygenation.
PMID: 17172824
a useful biomarker for predicting poor
prognosis of astrocytic tumors. It may also be a promising
target molecule for the improvement of therapeutic interventions
in astrocytomas.
PMID: 16428489
a tumor-associated transmembrane isoform of
the carbonic anhydrase with a high enzyme activity and a
functional involvement in the pH regulation and cell adhesion.
PMID: 15754010
CAIX plays an important role in the growth
and survival of tumor cells under normoxia and hypoxia, making
it a potential target for cancer therapy, but is not involved in
invasion.
PMID: 15342400
CA IX expression may detect not only actually
hypoxic tumor regions, but also the regions affected by hypoxia
and adverse microenvironmental stresses before biopsy or tumor
removal.
PMID: 15010840
CA IX has a capacity to modulate E-cadherin-mediated
cell adhesion via interaction with beta-catenin, which could be
of potential significance in hypoxia-induced tumor progression.
PMID: 14567991
MN/CA IX is a useful marker for the
differentiation between preneoplastic lesions and bronchial
non-small cell lung cancer in the lung.
PMID: 10573225
The co-occurrence of
MN/CA IX and Ki-67 in the same tumor cells indicates its
potential for use as a marker of increased proliferation in the
colorectal mucosa.
PMID: 9665489
CA IX expression status was the most reliable
hypoxia marker for predicting tumor aggressiveness.
PMID: 15935515
M75 mAb, recognizing CA IX antigen, has
targeting properties which could be potentially useful in
radioimmunodetection or radioimmunotherapy of human cervical
carcinomas and derived metastases.
PMID: 12687273
Diagnostic and Therapeutic Value
Allowing for potential prognostic variables
in a Cox regression analysis, CA IX remained a significant
independent predictor of survival (P=0.035).
PMID: 17213826
CA IX expression is strongly associated with
tumor progression and indicates a poor prognosis for patients
with stages I+II lung adenocarcinoma.
PMID: 17030461
CA IX expression, rather than VEGF positivity
in tumors, enables the identification of a subpopulation,
characterized by a more aggressive behavior and a poorer
prognosis.
PMID: 16495697
CAIX expression seems to be an important
predictor of outcome in renal cell carcinoma patients receiving
IL-2-based therapy and may enhance prognostic information
obtained from pathology specimens.
PMID: 15897568
CA IX expression of tumor cells may be an
indicator for poor disease-free survival in early-stage
non-small-cell lung cancer (NSCLC).
PMID: 15585626
a potential intrinsic marker of hypoxia,
predicts for poor prognosis in patients with deep, large,
high-grade soft tissue sarcoma.
PMID: 15240538
Ki67and CAIX are useful prognostic biomarkers
for RCC that improve the survival prediction and classification
of kidney cancer.
PMID: 15126876
CA IX is a potential target for future
therapy in head and neck squamous cell carcinoma (HNSCC).
PMID: 11431368
expression of CA9, but not CA12, in tumors is
associated with the presence of LN metastases and poorer
prognosis.
PMID: 17233814
The expression of the tumor-specific marker
CA9 in the peripheral blood is associated with decreased
disease-free survival in patients with renal cortical tumors.
This is the first study reporting on the prognostic value of
this peripheral blood-based tumor marker for kidney tumors.
PMID: 16698354
patients with low CA9 levels benefit more
from adjuvant treatment than do patients with high levels. Thus,
the determination of CA9 levels could aid in the selection of
patients who will not benefit from adjuvant therapy, and whose
prognosis will more likely improve with other treatment
modalities.
PMID: 12865916
Stratification of patients undergoing radical
radiotherapy using the CA9/MVD model may be useful for the
individualization of therapeutic strategies combining
antiangiogenesis and hypoxia targeting with radiotherapy.
PMID: 11705854
CA9 is a significant molecular marker in
renal clear cell carcinomas. Decreased CA9 expression is
independently associated with poor survival. CA9 can be used to
predict clinical outcome and identify high-risk patients in need
for adjuvant immunotherapy and CA9 targeted therapies.
PMID: 15711113
expression of the MN/CA9 antigen is indeed a
discriminator of significant lesions in AGUS Pap smear
diagnoses.
PMID: 10699902
MN/CA9 expression is a potential diagnostic
biomarker of renal cell carcinoma (RCC), especially the
clear-cell type, and can be targeted using molecular biological
techniques.
PMID: 10368188
MN/CA9 protein expression might have an
important clinical utility in the early detection and treatment
of renal cell carcinoma (RCC).
PMID: 9230182
CA IX is, however, a
weaker prognostic and predictive factor than HIF-1alpha, and its
association with HIF-1alpha does not modify the survival curve
neither response to therapy, compared to HIF-1alpha alone.
PMID: 17245699
CA IX is marker of poor prognosis in
premenopausal breast cancer patients and it is an independent
predictor of survival in patients with one to three positive
lymph nodes. As all these patients received locoregional
radiation therapy, CA IX may be associated with resistance to
radiotherapy.
PMID: 17085655
Applications
Flow Cytometry
The
expression of G250/mn/CA9 antigen by flow cytometry: its
possible implication for detection of micrometastatic renal
cancer cells.
PMID: 11205923
Immunohistochemistry
Standard immunohistochemical techniques were
used to study CA IX expression in 134 patients who underwent
curative resection for adenocarcinoma of the lung at our
hospital between January 1995 and December 1996.
PMID: 17030461
We evaluated the immunohistochemical
expression of CA IX and VEGF on paraffin-embedded material of
154 resection specimens: 39 esophageal, 73 cardiac, and 42
distal gastric adenocarcinomas (UICC classification).
PMID: 16495697
Using real-time PCR and immunohistochemistry,
we have examined the expression of carbonic anhydrase isozymes
(CA) I, II, III, IV, IX, XII, XIII and XIV in the brain, kidney,
stomach and colon of the wild-type, CA II-deficient (Car2-/-),
and CA IX deficient (Car9-/-) mice.
PMID: 16396925
We investigated the immunohistochemical
pattern of distribution of CA IX in a small series (14 cases) of
RCCs.
PMID: 15500003
Immunohistochemical analysis using a CAIX and
a Ki67 monoclonal antibody was performed on tissue microarrays
constructed from paraffin embedded specimens from 224 patients
treated with nephrectomy for clear cell renal carcinoma.
PMID: 15126876
Immunohistochemistry was used to examine
expression of CA IX in archival tissues of patients included in
various therapeutic trials for transitional cell carcinoma (TCC)
of the bladder.
PMID: 15069539
CA IX expression was immunohistochemically
detected in 2 independent study groups, totaling 184 patients,
and correlated with tumor characteristics, angiogenesis related
parameters and patient outcome by univariate analysis.
PMID: 14572156
Immunohistochemical analysis using a CAIX
monoclonal antibody was performed on tissue microarrays
constructed from paraffin-embedded specimens from patients (N =
321) treated by nephrectomy for clear cell RCC.
PMID: 12576453
CA IX expression was evaluated
immunohistochemically in pretreatment tumor biopsies. There was
a significant positive correlation between the level of tumor
hypoxia (HP5) and the extent of CA IX expression.
PMID: 11522632
CA IX expression was
evaluated by immunohistochemistry with a murine monoclonal
antibody, M75, in a series of 103 women treated surgically for
invasive breast cancer.
PMID: 11504747
Expression of CA9 and CD34, an endothelial
cell marker, was examined in serial paraffin-embedded sections
by immunohistochemistry in 25 grade 1, 17 grade 2, and 20 grade
3 meningiomas.
PMID: 17200340
Tissue from pre-RT biopsies performed in 198
of 918 patients recruited was analyzed for the
immunohistochemical expression of HIF-2 and CA9.
PMID: 16418497
Expression of CA9, IdUrd labeling, and
colocalization between IdUrd and CA9 was examined by
immunohistochemistry in biopsies of head and neck squamous cell
carcinomas.
PMID: 15671533
Immunohistochemical study of colorectal tumors for expression of
a novel transmembrane carbonic anhydrase, MN/CA IX, with
potential value as a marker of cell proliferation.
PMID: 9665489
Immunohistochemistry of carbonic anhydrase isozyme IX (MN/CA IX) in human gut reveals polarized expression in the epithelial cells with the highest proliferative capacity. PMID: 9524195
Western Blot
The expression of CA IX
and XII was examined by immunoperoxidase staining method and
western blotting.
PMID: 15488153
Expression of CA IX was determined by
immunoblotting in three HNSCC cell lines grown in normoxia and
hypoxia (pO(2) 0.1%) and three paired tumor and normal tissue
samples of HNSCC.
PMID: 11431368
Western blotting and immunohistochemical
analyses of human and animal tissues were performed using CA
IX-specific monoclonal antibody and rabbit antiserum to human CA
II.
PMID: 9024293
Using gastric cancer cell lines and tissues,
we studied expression of Ca9 by western blot analysis,
immunohistochemistry, and polymerase chain reaction.
PMID: 15951534
Western blot analysis from efferent duct
samples revealed specific bands for CA IX and CA XII, confirming
that the immunohistochemical stainings represent these isozymes.
PMID: 11420383