Elevated levels of CXC chemokine connective tissue activating peptide (CTAP)-III in lung cancer patients

Despite advances in treatments, lung cancer has been the leading cause of cancer-related deaths in the United States for the past several decades. Recent findings from the National Lung Screening Trial reveal that low-dose helical computed tomography (CT) scan screening of high-risk individuals reduces lung cancer mortality. This suggests that early detection is of key importance to improving patient outcome. However, of those screened with CT scans, 25% had positive scans that require further follow-up studies which often involve more radiation exposure and invasive tests to reduce false positive results. The purpose of this study was to identify candidate plasma biomarkers to aid in diagnosis of lung cancer in at-risk individuals. We found increased expression of the CXC chemokine connective tissue-activating peptide (CTAP)-III from plasma specimens of lung cancer patients compared to at-risk control subjects. Identification of the peptide was confirmed by the addition of an anti-NAP-2 antibody that recognizes CTAP-IIIand NAP-2. We also quantified and verified the increased levels of plasma CTAP-III with ELISA in patients with lung cancer (mean ± SD, 1859 ± 1219 ng/mL) compared to controls (698 ± 434 ng/mL; P<0.001). Our findings demonstrate elevated plasma levels of CTAP-III occur in lung cancer patients. Further studies are required to determine if this chemokine could be utilized in a blood-based biomarker panel for the diagnosis of lung cancer.

Lee G, et al. Am J Transl Res. 2011 May 15;3(3):226-33. Epub 2011 Apr 2.

Discovery and identification of potential biomarkers of pediatric acute lymphoblastic leukemia

BACKGROUND: Acute lymphoblastic leukemia (ALL) is a common form of cancer in children. Currently, bone marrow biopsy is used for diagnosis. Noninvasive biomarkers for the early diagnosis of pediatric ALL are urgently needed. The aim of this study was to discover potential protein biomarkers for pediatric ALL.

METHODS: Ninety-four pediatric ALL patients and 84 controls were randomly divided into a "training" set (45 ALL patients, 34 healthy controls) and a test set (49 ALL patients, 30 healthy controls and 30 pediatric acute myeloid leukemia (AML) patients). Serum proteomic profiles were measured using surface-enhanced laser desorption/ionization-time-of-flight mass spectroscopy (SELDI-TOF-MS). A classification model was established by Biomarker Pattern Software (BPS). Candidate protein biomarkers were purified by HPLC, identified by LC-MS/MS and validated using ProteinChip immunoassays.

RESULTS: A total of 7 protein peaks (9290 m/z, 7769 m/z, 15110 m/z, 7564 m/z, 4469 m/z, 8937 m/z, 8137 m/z) were found with differential expression levels in the sera of pediatric ALL patients and controls using SELDI-TOF-MS and then analyzed by BPS to construct a classification model in the "training" set. The sensitivity and specificity of the model were found to be 91.8%, and 90.0%, respectively, in the test set. Two candidate protein peaks (7769 and 9290 m/z) were found to be down-regulated in ALL patients, where these were identified as platelet factor 4 (PF4) and pro-platelet basic protein precursor (PBP). Two other candidate protein peaks (8137 and 8937 m/z) were found up-regulated in the sera of ALL patients, and these were identified as fragments of the complement component 3a (C3a).

CONCLUSION: Platelet factor (PF4), connective tissue activating peptide III (CTAP-III) and two fragments of C3a may be potential protein biomarkers of pediatric ALL and used to distinguish pediatric ALL patients from healthy controls and pediatric AML patients. Further studies with additional populations or using pre-diagnostic sera are needed to confirm the importance of these findings as diagnostic markers of pediatric ALL.

Shi L. et al. Proteome Sci. 2009 Mar 16;7:7.

NAP-2/CTAP III(Human) ELISA Kit

Code No.: SK00434-01

Size: 96T

Standard range:31.2-2000 pg/ml

Sensitivity:15 pg/ml

Sample Type: serum, plasma

Dilution Factor: 1000-2000 for serum

Intra-CV:4-6%

Inter-CV: 8-12%

Data Sheet: PDF

Human Platelet Basic Protein (PBP)/CXCL7/NAP2 Rec

Code No.: 00756-01-100

Size: 100 µg

Protein ID: P02775

Gene ID: 5473

MW: 14 KD

Tag: His Tag on N-Terminus

Expressed: E. Coli

Purity: 95%

Data Sheet: PDF

Anti human Platelet Basic Protein (PBP) Rec

Code No.: A00756-01-100

Size: 100 µg

Target Protein ID: P02775

Target Gene ID: 5473

Host: Rabbit

Immunogen: Human PBP rec

Antibody Type: Purified IgG

Purification: Protein A

Applications: ELISA, IHC (2-4 ug/ml)

Data Sheet: PDF