PLK1 and EGFR targeted nanoconstruct as a monotherapy and a radiation sensitizer for lung cancer

Lung cancer is the leading cause of cancer mortality, exceeding deaths from colon, breast, and prostate

cancers combined. Resistance to chemo and targeted therapy is very common. Radiation therapy (RT)

remains a key treatment in about 60% of lung cancer patients.

We seek to develop a novel nanotherapeutic (termed PETTRA) that homes to EGFR+ lung tumors and

delivers siRNA against Polo-like kinase 1 (siPLK1). EGFR is an ideal homing target since it is routinely profiled;

and is overexpressed in 50% of lung cancer patients. PLK1 is among the strongest cancer targets due to its

crucial roles in cell division and DNA repair, and inhibiting PLK1 leads to G2/M cell cycle arrest and apoptotic

death. Cells in G2/M arrest are also most sensitive to radiation. Thus, PETTRA is hypothesized to be effective

as a monotherapy and as a radiation sensitizer for lung cancer. Or prototype PETTRA has demonstrated good

safety and efficacy for such dual proposes in cells and in mice. Herein, we propose to further optimize the

material to enhance the efficacy and safety. While lipid-based particles have been effective at delivering

siRNAs to the liver with 4 FDA approved drugs in the past few years, no platform has been successful in solid

tumors yet. We have solved the limitations of nanoparticle delivery and achieved long circulation half-life (e.g.,

25 hrs in monkeys), 10-fold increased siRNA accumulation in tumors, specific delivery to target cells (by 5 to 8-

fold over normal cells), excellent PLK1 gene knock-down (e.g., by 84%), and tumor inhibition (e.g., by 90%) in

mouse models. Tech-transfer for GMP manufacturing of our nanoparticles has been accomplished.

Phase I: In Aim 1, we will optimize (by evaluating various EGFR antibody drugs (Ab) and increasing the

loading of EGFR antibody and siPLK1 by at least 3-fold) and screen for the lead constructs that yield

hydrodynamic size 70%

cell death in EGFR+ lung cancer cells, and safety to normal cells (