When A&G Pharmaceutical and the University of Maryland Greenebaum Comprehensive Cancer Center initiated a study to examine the correlation between serum progranulin/GP88 level, a tumorigenesis driver and breast cancer progression, they needed to develop a reliable sandwich ELISA assay. A&G tasked its service division Precision Antibody (PA) to develop an assay able to measure serum and plasma GP88 that would be appropriate for the clinical study.

PA, known for its fast timeline and high success rate, developed specific human progranulin/GP88 monoclonal antibodies. PA then used Octet analysis to select antibodies with the best biochemical characteristics (high affinity, low off rate) for establishing a suitable sandwich ELISA. The Quantification ELISA PA developed is so sensitive that it can be used with biological samples known for their low progranulin/GP88 level such as cerebrospinal fluid, in addition to serum and plasma. This ELISA allows for Progranulin/GP88 investigation in neurodegenerative diseases and for the detection of CNS metastasis1.

The published study (Tkaczuk et al, Clin. Breast Cancer) showed a strong correlation between progranulin/GP88 and disease progression for metastatic breast cancer patients. Patients with lower levels of progranulin/GP88 had a four-fold increase in survival compared to those with higher levels. The study also established that measuring serum progranulin/GP88 had clinical utility for monitoring patients’ response to therapy as well as providing additional disease status information to CA15-3, currently used in the standard of care. These promising results complement our previous findings showing that high level of progranulin/GP88 expression in paraffin embedded tumor tissues is associated with increased recurrence and mortality for early stage breast cancer patients2.

To read the full research paper click here.

Association of Serum Progranulin Levels With Disease Progression, Therapy Response and Survival in Patients With Metastatic Breast Cancer.
Tkaczuk KHR, Hawkins D, Yue B, Hicks D, Tait N, Serrero G.
Clin Breast Cancer. 2019 Dec 5. pii: S1526-8209(19)30758-X. doi: 10.1016/j.clbc.2019.11.010. [Epub ahead of print]

For more information regarding Dr. Serrero’s GP88 research please see:

1Higher levels of progranulin in cerebrospinal fluid of patients with lymphoma and carcinoma with CNS metastasis.
Kimura A, Takemura M, Serrero G, Yoshikura N, Hayashi Y, Saito K, Inuzuka T.
J Neurooncol. 2018 May;137(3):455-462. doi: 10.1007/s11060-017-2742-z. Epub 2018 Jan 16.
PMID: 29340960

2Progranulin (GP88) tumor tissue expression is associated with increased risk of recurrence in breast cancer patients diagnosed with estrogen receptor positive invasive ductal carcinoma.
Serrero G, Hawkins DM, Yue B, Ioffe O, Bejarano P, Phillips JT, Head JF, Elliott RL, Tkaczuk KR, Godwin AK, Weaver J, Kim WE.
Breast Cancer Res. 2012 Feb 8;14(1):R26.

To order anti-progranulin/GP88 antibodies (Cat. # AG10009) click here.

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