Abstract: The present disclosure relates to a method for selecting a tumor neoantigenic peptide wherein said method comprises: —a step of identifying, among mRNA sequences from cancer cells of a subject, a fusion transcript sequence comprising a transposable element (TE) sequence and an exonic sequence, and including an open reading frame (ORF), and —a step of selecting a tumor neoantigenic peptide of at least 8 amino acids, encoded by a part of said ORF of the fusion transcript sequence, wherein said ORF overlaps the junction between the TE and the exonic sequence, is pure TE and/or is non-canonical, and wherein said tumor neoantigenic peptide binds to at least one Major Histocompatibility Complex (MHC) molecule of said subject. The present disclosure also relates to tumor neoantigenic peptide obtained according to the present method, vaccine or immunogenic composition, antibodies and immune cells derived thereof and their use in therapy of cancer.

Abstract: The present application relates to a tumor specific neoantigenic peptide, wherein said peptide is encoded by a part of an ORF sequence from a transcript associated with a SF3B1 or a SF3B1-like mutation, comprises at least 8 amino acids and binds at least one MHC molecule with an affinity of less than 500 nM; and is not expressed in normal healthy cells. The present application further relates to vaccine or immunogenic composition, antibodies, T cell receptors, polynucleotides, vectors and immune cells derived thereof as well as their use in therapy of cancer.

Abstract: The invention relates to the domain of anemia, iron overload and myeloid malignancy. The inventors identify a variant transcript of ERFE specific of SF3B1MUT MDS that contributes to increased concentration of ERFE protein leading to hepcidin suppression and iron accumulation in patients. This transcript contains an in-frame added intronic sequence of 12 nucleotides not inducing a stop codon that may be translated into a variant protein with an additional 4 amino acids. By using deep mass spectrometry, they identified a peptide corresponding to the added polypeptide VPQF (SEQ ID NO: 5) demonstrating the active production of a variant protein by bone marrow erythroblasts of patients with a SF3B1-mutated MDS. This variant can be used as a pertinent biomarker of clonal erythropoiesis for monitoring treatments of anemia in SF3B1MUT patients.