The HSPA1L Knockout NCI-H1975 Polyclonal Cells consist of a CRISPR/Cas9-edited polyclonal population of the human lung adenocarcinoma cell line NCI-H1975, in which the HSPA1L gene has been disrupted to abrogate HSP70 family chaperone function. This knockout model avoids clonal selection and provides a heterogeneous pool for studying loss-of-function effects in a genetically diverse setting.
The parental NCI-H1975 line is derived from a non-small cell lung adenocarcinoma and carries the activating EGFR L858R mutation along with the T790M gatekeeper mutation, conferring resistance to first-generation EGFR TKIs. It is extensively used in oncology research to model acquired drug resistance and evaluate next-generation therapeutic strategies.
HSPA1L encodes an inducible HSP70 chaperone that maintains proteostasis by folding nascent polypeptides, refolding misfolded proteins, and targeting damaged proteins for degradation. Its transcription is activated by HSF1 under conditions such as heat shock, oxidative stress, and hypoxia. In the cellular network, HSPA1L collaborates with co-chaperones HSP40, BAG3, and CHIP, and cooperates with HSP90 to stabilize oncogenic clients including mutant EGFR and AKT. This regulation feeds into MAPK and PI3K-AKT signaling and modulates apoptotic effectors like BAX and BCL2.
Disruption of HSPA1L in the EGFR-mutant/T790M context is expected to compromise the stability and signaling of key client proteins, leading to reduced cell proliferation and heightened susceptibility to stress-induced apoptosis, potentially reversing TKI resistance. Thus, these cells offer a unique tool to probe the role of the HSP70 chaperone system in maintaining the oncogenic state and in mediating resistance to targeted therapies.
Applications include Western blot and RT-qPCR analysis of HSP70 family members, co-immunoprecipitation of HSPA1L with EGFR or AKT, and thermal shift assays to gauge client stability. Functional assays such as CellTiter-Glo viability testing, Annexin V apoptosis assays, colony formation, and drug sensitivity profiling with gefitinib or osimertinib are highly compatible. The polyclonal knockout cells enable investigations into HSP70-driven drug resistance, synthetic lethality screens with HSP inhibitors, and proteostasis studies in NSCLC. For more information, please contact Ascent Research.
