Human Lymphoblastoid Cell Line Panels: Novel Tools for Assessing Shared Drug Pathways

Abstract

Aims: While powerful in silico tools are emerging for predicting drug targets and pathways, general in vitro tools for assessing such predictions are lacking. We present a novel in vitro method for distinguishing shared versus distinct drug pathways based on comparative cell growth inhibition profiles across a small panel of human lymphoblastoid cell lines (LCLs) from individual donors. Materials & methods: LCLs from unrelated healthy donors were examined in parallel for growth inhibition profiles of various drugs, including antidepressants (paroxetine, fluoxetine, fluvoxamine, citalopram, amitriptyline and imipramine); anticancer drugs (5-fluorouracil, 6-mercaptopurine, azathioprine, methotrexate and resveratrol); steroid drugs (dexamethasone, beclomethasone and prednisolone); and antipsychotic drugs (haloperidol and clozapine). Cell growth was assessed by the colorimetric 2,3-bis(2-methoxy-4-nitro-5-sulfophenly)-5-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide method following 72 h of drug exposure. Results: LCLs from unrelated individuals exhibited a wide range of sensitivities to growth inhibition by a given drug, which were independent of basal cell replication rates. Yet, each individual cell line demonstrated a consistent sensitivity to multiple drugs from the same family. High goodness-of-fit values (R² > 0.6) were consistently observed for plots comparing the growth-inhibition profiles for paired drugs sharing a similar pathway, for example antidepressants, steroid drugs, antipsychotics, or 6-mercaptopurine compared with azathioprine, but not for drugs with different pathways. The method‘s utility is demonstrated by the observation that chlorpheniramine, an antihistamine drug long suspected to also possess antidepressant-like properties, exhibits a growth-inhibition profile very similar to antidepressants. Conclusion: Comparing the growth-inhibition profiles of drugs (or compounds) of interest with the profiles of drugs with known pathways may assist in drug pathway classification. The method is useful for in vitro assessment of in silico-generated drug pathway predictions and for distinguishing shared versus distinct pathways for compounds of interest. Comparative transcriptomics analysis of human lymphoblastoid cell lines exhibiting ‘edge‘ sensitivities can subsequently be utilized in the search for drug response biomarkers for personalized pharmacotherapy. The limitations and advantages of the method are discussed.

KEYWORDS::

• anticancer drug
• antipsychotic
• cell growth inhibition
• chlorpheniramine
• drug pathway
• gene-expression profilin
• goodness-of-fit of linear regression
• human lymphoblastoid cell line
• resveratrol
• serotonin reuptake inhibitor antidepressant
• steroid drug
• tricyclic antidepressant

Acknowledgments

We thank the anonymous donors of the NLGIP biobank at Tel Aviv University, Israel, whose altruism and trust in biomedical research have made this study possible. We thank Shimon Efrat and Michael Korostishevsky (Tel-Aviv University, Israel) for insightful discussions, and Mor Cohen (Bar-Ilan University, Israel) for help with the construction of the heat-map.

Financial & competing interests disclosure

David Gurwitz was supported by The Yoran Institute for Human Genome Research and by The National Institute for Psychobiology in Israel founded by the Charles E Smith Family. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Additional information

Funding

David Gurwitz was supported by The Yoran Institute for Human Genome Research and by The National Institute for Psychobiology in Israel founded by the Charles E Smith Family. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. No writing assistance was utilized in the production of this manuscript.