The aim of the present study is to evaluate the expression of a large panel of microRNAs, already known and validated in other ortopedic pathologies and bone metabolism, in the plasma of Adolescent Idiopathic Scoliosis (AIS) patients. The deregulated microRNAs identified will be then validated and computational analyzes will determine their potential involvement in the metabolism of bone and/or cartilage tissue in order to correlate the results obtained with the clinical data of the AIS patients. The investigators aimed to develop a microRNAs panel to further validate in a larger population of AIS patients in order to produce a device for the diagnosis and prognosis of Molecular-based AIS.

MATERIALS AND METHODS: 1) Collection of a venous blood sample from patients enrolled with AIS or controls, and subsequent separation of plasma; 2) Isolation of circulating total RNA from the plasma of AIS patients (Kit Invitrogen: Total RNA Isolation Reagent) and preparation of microRNA samples (TaqMan™ MicroRNA Reverse Transcription Kit); 3) Analysis of microRNA expression profiles by micro-array technique (Taqman Advanced miRNAs Human CardA + B); 4) Validation of deregulated microRNAs by single-qRT-PCR assay and computational functional analyses; and 5) In vitro studies to investigate the molecular role of the microRNAs identified within the mechanisms of bone remodeling.

Enrollment Procedures:

Patients considered eligible will be enrolled in the study, after providing a written informed consent. Healthy subjects (control group) will be recruited, on a voluntary basis, by means of an announcement published on the web page of the Rizzoli Orthopedic Institute (www.ior.it), "News" section.

Data Collection: Clinical data will be retrieved by patient's source document. A protocol-specific CRF reporting the results of the analyses will be provided. A CRF is required and should be completed for each included subject.

Ethics: The clinical trial protocol and its documents will be sent before initiating the study to the competent Authorities and Ethics Committees of each participating country for its approval. The responsible investigator will ensure that this study is conducted in agreement with either the most updated Declaration of Helsinki and all the international and local laws that apply to clinical trials and to patient protection. The protocol has been written, and the study will be conducted according to the principles of the ICH Harmonized Tripartite Guideline for Good Clinical Practice (ref: http://www.emea.eu.int/pdfs/human/ich/013595en.pdf).

Informed Consent: All patients will be informed, by the investigator, of the aims of the study, the possible risks and benefits that will derive from the study participation. The Investigator must clearly inform that the patient is free to refuse participation in the study and that can withdraw consent at any time and for any reason. The patients will be informed as to the strict confidentiality of their personal data, but the medical records of the patients enrolled may be reviewed for trial purposes by authorized individuals other than their treating physician. The informed consent procedure must conform to the ICH guidelines on Good Clinical Practice. This implies that "the written informed consent form should be signed and personally dated by the patient or by the patient's legally acceptable representative".

The Investigator must also sign the Informed Consent form, and will keep the original at the site and a copy of the original must be handed to the patient.

The competent ethics committee for each Institution participating to the study must validate local informed consent documents before the study can be opened. It will be emphasized that the participation is voluntary and that the patient is allowed to refuse further participation in the study whenever he/she wants. This will not prejudice the patient's subsequent care.

General Principles for Human Biological Material (HBM) collection: Human biological material (HBM) collection involves the collection and storage of biological material, residual biological material or derivatives in compliance with ethical and technical requirements. Biological material (blood samples) will be centralized and stored at Istituto Ortopedico Rizzoli - Dipartimento Rizzoli-Sicilia, Bagheria (Palermo). From here, the biological material will be used and stored according with the sample characteristic and applicable regulation.

Plasma and circulating total RNA obtained from blood will be stored inside sterile containers (falcon, tubes, eppendorf) in a freezer at the temperature of -80 °C at the Istituto Ortopedico Rizzoli - Dipartimento Rizzoli Sicilia.

The following principles apply to storage of HBM: (a) The Istituto Ortopedico Rizzoli will have a designated person responsible for collection and will act as a communication point; (b) The collected HBM should be documented, i.e. the amount remaining and its location. act as a communication point; and (c) The storage and use of biological material will take place in accordance with the standards of good laboratory practice (GLP) and applicable legislation.

Confidentiality: In order to ensure confidentiality of clinical trial data as disposed the national and European applicable regulation, data will be only accessible for the trial Sponsor and its designees, for monitoring/auditing procedures, the Investigator and collaborators, the Ethics Committee of each corresponding site and the Health Authority. Investigator and the Institution will allow access to data and source documentation for monitoring, auditing, Ethic Committee revision and inspections of Health Authority, but maintaining at all times subject personal data confidentiality as specified in the applicable regulation.

The Investigator must guarantee that patient anonymity is kept at all times and their identity must be protected from unauthorized persons and institutions.

All patients included in the study will be identified with a numeric code, so that no identifiable personal data will be collected. The Investigator must have and conserve a patients' inclusion registry where it figures the personal data of the patient: name, surname, address and corresponding identification code into the study, this register will be kept on the Investigator File.

Publication policy and data ownership: The principal investigator of the study is responsible for the final report, of the publication publish all the data collected as described in the protocol and will ensure that the data are reported responsibly and consistently. In particular, the publication of data deriving from the present study will take place independently of the results obtained. The transmission or dissemination of data, through scientific publications and / or presentation at conferences, congresses and seminars, will take place exclusively following the purely statistical processing of the same, or in an absolutely anonymous form. All the study data are owned by the sponsor.

Inclusion Criteria:

Cases:

• Age between 11-17 years
• Diagnosis of idiopathic scoliosis with a Cobb angle> 10 °
• Minimum follow-up of two years
• Clinical data and radiological tests available and no surgical treatment prior to enrollment in the study

Controls:

• Age between 11-17 years
• Healthy subjects not affected by orthopedic and oncological diseases

Exclusion Criteria:

• Severe cognitive impairment or psychiatric disorders
• Patients with scoliosis due to secondary causes
• Women of childbearing age must not be pregnant

A maximum number of 20 AIS patients in a ratio of 5:1 between females and males is expected to be enrolled; 10 healthy controls, of which 5 females and 5 males will be enrolled. Patients and control group (healthy volunteers) will be enrolled in the clinical trial only after providing written informed consent.