The ChemoFx® Assay: An Ex Vivo Chemosensitivity and Resistance Assay for Predicting Patient Response to Cancer Chemotherapy

Abstract

The ChemoFx Assay is an ex vivo assay designed to predict the sensitivity and resistance of a given patient's solid tumor to a variety of chemotherapy agents. A portion of a patient's solid tumor, as small as a core biopsy, is mechanically disaggregated and established in primary culture where malignant epithelial cells migrate out of tumor explants to form a monolayer. Cultures are verified as epithelial and exposed to increasing doses of selected chemotherapeutic agents. The number of live cells remaining post-treatment is enumerated microscopically using automated cell-counting software. The resultant cell counts in treated wells are compared with those in untreated control wells to generate a dose-response curve for each chemotherapeutic agent tested on a given patient specimen. Features of each dose-response curve are used to score a tumor's response to each ex vivo treatment as "responsive," "intermediate response," or "non-responsive." Collectively, these scores are used to assist an oncologist in making treatment decisions.

An in vitro chemoresponse assay defines a subset of colorectal and lung carcinomas responsive to cetuximab

“…After a 72 hour exposure to various doses of cetuximab, the primary cultures were assayed using the ChemoFx DRM. 13 Of the 67 colorectal carcinoma specimens received and tested using ChemoFx, 2 primary cultures (3%) were R, 3 (4.5%) were IR and 62 (92.5%) were NR to cetuximab (Fig. 5A).…”

“…12 The ChemoFx ® drug response marker (DRM), an in vitro chemosensitivity and resistance assay, is a test that quantifies an individual cancer patient's in vitro tumor response to various chemotherapeutic and biologic agents through outgrowth of the tumor into an adherent monolayer in culture. 13 The test can be performed on samples as small as 35 mg, 13,14 and immunocytochemistry (ICC) analysis is performed on the primary cultures to ensure that ChemoFx is measuring the effects of therapy on the malignant epithelial cells (instead of benign fibroblasts). 15 In addition, robotic liquid handling systems and automated imaging systems have been incorporated into ChemoFx to increase consistency and reproducibility, as well as throughput, thereby controlling many of the inconsistencies historically associated with cell-based assay systems.…”

Efficacy of ChemoID® guided drug selection for palliative chemotherapy in advanced recurrent high-grade ovarian adenocarcinoma: Case study

“…However, this approach has been hampered by the chemotherapy testing only being performed on bulk of tumor cells derived from cancer biopsies. [12][13][14][15][16][17][18][19][20][21] Ovarian cancers contain a population of self-renewing cancer stem cells (CSCs) that contribute to tumorigenesis, treatment resistance and tumor recurrence. [22][23][24][25][26][27][28][29] ChemoID …”

An Emerging Role of Biorepositories In Personalized Medicine: Isolation and Processing of Primary Tumor Cells For the Establishment of 3d Tumor Cultures From Solid Tumor Specimens

“…In contrast, the critical importance of technologies related to the derivation, short term culture, and testing of primary tumor cells from solid tumors is increasingly recognized (for a recent review see 2). Short-term primary cultures of tumor cells derived from pieces of solid tumors have been used for predicting anticancer drug responses [3,4]. Observations suggest that individualized drug sensitivity testing of solid tumors through the isolation and culturing primary tumor cells in 3D may soon become routine and modern tissue repositories will need to be ready to support these activities as they expand from their traditional research role to active participation in personalized medicine [5].…”