In this thesis, it has been summarized the evidence for microRNA (miRNA) involvement in lung cancer and in head and neck cancer before and after radiotherapy. In recent years it has emerged that microRNAs are involved in tumorigenesis and negatively regulate gene expression, thus affecting the expression of oncogenes and tumor suppressors. MicroRNAs are endogenous small, noncoding RNAs that regulate gene expression post-transcriptionally, influencing many processes including cellular sensitivity to radiation. Profiling studies demonstrate that miRNA expression levels change in response to radiation, while certain miRNAs, when overexpressed or knocked down, alter radiosensitivity. This thesis work is part of a study conducted by the Laboratory of Neuro-Radio Experimental Biology of the University of Pavia in collaboration with the S.C. Oncological Radiotherapy of the I.R.C.C.S. Foundation San Matteo Polyclinic of Pavia. Patients who voluntarily joined the study underwent venous blood sampling before radiotherapy, at the end, 45-60 days and 6 months after radiotherapy. From the blood samples taken, the total RNA was extracted which was then retrotranscribed in cDNA. Three miRNAs were selected for the analyzes: miR-21, miR-191 and miR-421. SnRNA U6 (small nuclear RNA) was used as endogenous control. The U6-1 gene is a constitutive gene coding for a small nuclear RNA, which maps to human chromosome 15. Through quantitative real-time analysis (qRT-PCR), using specific LNA probes synthesized in the sequences of interest (complementary to the target mRNA), quantitative variations of the three microRNAs were determined. Finally, miRNA expression levels were compared before radiotherapy with those after radiotherapy.
Il presente lavoro di tesi ha previsto lo studio dell’espressioni di miRNA in pazienti affetti da neoplasia del polmone e del distretto testa collo sottoposti a radioterapia. Negli ultimi anni è emerso che i microRNA sono coinvolti nella tumorigenesi e regolano negativamente l’espressione genica, influendo di conseguenza sull’espressione di oncogeni e oncosoppressori. I microRNA sono piccoli RNA endogeni non codificanti che regolano l’espressione genica a livello post-trascrizionale, influenzando molti processi cellulari, inclusa la sensibilità cellulare alle radiazioni. Studi sui profili di miRNA dimostrano che i livelli di espressione dei miRNA cambiano in risposta alle radiazioni, quando si trovano ad alti livelli o bassi alterano la radiosensibilità. Il presente lavoro di tesi si inserisce in uno studio condotto dal Laboratorio di Neuro-Radio Biologia Sperimentale dell’Università di Pavia in collaborazione con la S.C. Radioterapia Oncologica della Fondazione I.R.C.C.S. Policlinico San Matteo di Pavia. I pazienti che hanno aderito volontariamente allo studio, sono stati sottoposti al prelievo di sangue venoso, effettuato prima della radioterapia, al termine, a 45-60 giorni e a 6 mesi dalla radioterapia. Dai campioni di sangue prelevato, è stato estratto l’RNA totale che è poi stato retrotrascritto in cDNA. Per le analisi sono stati scelti tre miRNA: miR-21, miR-191 e miR-421. Come controllo endogeno è stato utilizzato snRNA U6 (small nuclear RNA). Il gene U6-1 è un gene costitutivo e codifica per un piccolo RNA nucleare, che mappa sul cromosoma 15 umano. Tramite analisi quantitativa in real-time (qRT-PCR), utilizzando specifiche sonde a LNA sintetizzate nelle sequenze di interesse (complementari all’mRNA target), sono state determinate le variazioni quantitative dei tre microRNA. Infine, sono stati confrontati i livelli di espressione dei miRNA prima la radioterapia con quelli dopo la radioterapia.
Studio dei valori di espressione di miRNA-21, -191, -421 in pazienti con tumore del polmone e del distretto testa-collo prima e dopo radioterapia.
STUDIOSO, SILVIA
2016/2017
Abstract
In this thesis, it has been summarized the evidence for microRNA (miRNA) involvement in lung cancer and in head and neck cancer before and after radiotherapy. In recent years it has emerged that microRNAs are involved in tumorigenesis and negatively regulate gene expression, thus affecting the expression of oncogenes and tumor suppressors. MicroRNAs are endogenous small, noncoding RNAs that regulate gene expression post-transcriptionally, influencing many processes including cellular sensitivity to radiation. Profiling studies demonstrate that miRNA expression levels change in response to radiation, while certain miRNAs, when overexpressed or knocked down, alter radiosensitivity. This thesis work is part of a study conducted by the Laboratory of Neuro-Radio Experimental Biology of the University of Pavia in collaboration with the S.C. Oncological Radiotherapy of the I.R.C.C.S. Foundation San Matteo Polyclinic of Pavia. Patients who voluntarily joined the study underwent venous blood sampling before radiotherapy, at the end, 45-60 days and 6 months after radiotherapy. From the blood samples taken, the total RNA was extracted which was then retrotranscribed in cDNA. Three miRNAs were selected for the analyzes: miR-21, miR-191 and miR-421. SnRNA U6 (small nuclear RNA) was used as endogenous control. The U6-1 gene is a constitutive gene coding for a small nuclear RNA, which maps to human chromosome 15. Through quantitative real-time analysis (qRT-PCR), using specific LNA probes synthesized in the sequences of interest (complementary to the target mRNA), quantitative variations of the three microRNAs were determined. Finally, miRNA expression levels were compared before radiotherapy with those after radiotherapy.È consentito all'utente scaricare e condividere i documenti disponibili a testo pieno in UNITESI UNIPV nel rispetto della licenza Creative Commons del tipo CC BY NC ND.
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https://hdl.handle.net/20.500.14239/18183