A research platform for miRNA-based treatment of multiple myeloma and chronic lymphoctic leukemia

MicroRNAs (miRNAs) are a class of small non-coding RNAs which regulate gene

expression at the post-transcriptional level. miRNAs play a role in tumorigenesis acting as

oncogenes or tumor suppressor genes. Aberrant miRNA expression is associated to

prognosis and therapeutical response. Deregulation of miRNA expression is involved in

the pathogenesis of chronic lymphocytic leukemia (CLL) and multiple myeloma (MM)

where miRNAs are important therapeutic targets. Two approaches can be theoretically

used to achieve a therapeutic effect by targeting the miRNA regulatory network: i) enforce

the activity of anti-tumor miRNAs (miRNAs as drug), ii) inhibit the activity of pro-tumor

miRNAs (miRNAs as target) by means of antagomirs.

The aim of our project is to exploit miRNAs as drugs or targets in innovative therapeutic

strategies for CLL and MM using novel in vitro and in vivo preclinical models and delivery

nanotechnologies. We propose an experimental platform which includes all steps from

target identification to FIRST in HUMAN studies. In Task 1, miRNAs, whose expression is

consistently deregulated in CLL and MM, as well as in non-tumor cells of the tumor bone

marrow microenvironment (BMM), will be defined by molecular profiling of clinical samples

from the framework of nationwide clinical trials. In Task 2, we will evaluate the effects

induced by targeting deregulated miRNAs on cell survival/proliferation and on selected

pathways using molecular profiling technologies. Task 3 will be devoted to the design,

preparation, characterization and evaluation of liposomes, supramolecular lipidic

aggregates (SLAs) and colloidal polymeric carriers for in vivo delivery of engineered

miRNAs or antagomirs. Specifically, we will attempt to functionalize nanocarrier surfaces

by humanized mAbs against anti-CLL and -MM-associated antigens. Reagents produced

in this Task will be tested in murine models of CLL and MM (Task 4). The investigation will

take benefit of the E-µu-TCL1 transgenic mouse model of human CLL and of a NOD/SCID

mouse model for in vivo expansion of CLL cells. Moreover, we will use the SCID-hu model

of human MM and an innovative in vivo system (SCID-synth-hu) based on a 3-D bone-like

poly-ε-caprolactone biopolymeric scaffold coated in the 3-D space with BMSCs, which

allow the growth of primary MM cells in human fetal or adult autologous BMM,

respectively. Task 5 will afford the clinical grade production of selected bioreagents for

preclinical pharmacokinetics and toxicology in animals in order to achieve an

investigational new drug status. These miRNAs/antagomirs carrying nanovectors will

finally proceed to early clinical trials (Phase 0-I) for FIRST in HUMAN evaluation (Task 6).

The possibility of in vivo monitoring of effective nanovector delivery with unique

sophisticated preclinical models as well as the chance of real-time monitoring of patients

undergoing early clinical trials will provide an array of opportunities for re-designing the

molecular reagents and improve delivery strategies. The design of this project as a

platform will provide the best information exchange among investigators and will allow re-

direction of the experimental flow on the basis of available information in order to achieve

the final goal of new treatments for CLL and/or MM by a timely translational network.