Laura Zannini

Istituto di Genetica Molecolare “Luigi Luca Cavalli-Sforza” – CNR
Via Abbiategrasso, 207
27100 Pavia
Tel: 0382 546363
E-mail: laura.zannini@igm.cnr.it
Curriculum Vitae – Download
Elenco completo delle pubblicazioni – Download
Attività di ricerca
L’interesse principale del nostro laboratorio è lo studio della risposta al danno del DNA (DDR), una complessa cascata di trasduzione del segnale che le cellule hanno sviluppato per contrastare le lesioni al genoma causate da agenti esogeni o endogeni. Ogni giorno le cellule sono esposte ad agenti genotossici che possono danneggiare il DNA e, se queste lesioni non vengono riparate correttamente, possono causare instabilità genomica e tumori. Infatti, mutazioni nelle proteine della DDR sono state trovate in molti tipi di tumore. Tuttavia, sebbene possano favorire la tumorigenesi, i difetti della DDR costituiscono anche una debolezza che può essere sfruttata dalla terapia poiché i farmaci in grado di indurre più lesioni di quelle consentite dalla capacità di riparazione delle cellule tumorali possono essere utili nella terapia dei pazienti oncologici. Proprio per questo motivo è importante, e soprattutto interessante, chiarire i meccanismi molecolari alla base della DDR e della riparazione delle lesioni del DNA.
Durante i nostri studi, ci siamo concentrati in particolare sulla cascata di trasduzione del segnale mediata da ATM-Chk2 e ci siamo occupati della ricerca e caratterizzazione delle proteine che interagiscono con Chk2, una chinasi con un ruolo importante nella regolazione dell’attivazione dei checkpoint del ciclo cellulare in risposta al danno al DNA. Recentemente, abbiamo identificato e caratterizzato la funzione di DBC1 (Deleted in breast cancer-1, CCAR2, KIAA1967), una proteina nucleare la cui attività è regolata da ATM e ATR e che, collaborando con Chk2, partecipa alla DDR e alla regolazione dell’apoptosi. Durante questi studi abbiamo scoperto che anche TSPYL2 (Testis Specific Y-encoded Like protein 2) è un altro componente della DDR e che condivide con DBC1 importanti funzioni nella regolazione dell’attività di p53 e dell’induzione dell’apoptosi in risposta al danno al DNA. L’obiettivo principale del nostro laboratorio è quindi quello di studiare come DBC1 e TSPYL2 cooperano e partecipano alla DDR, come sono coinvolti nella tumorigenesi e nella progressione del cancro e se in futuro potranno essere dei buoni candidati per la prognosi e la terapia del cancro.
Gruppo di ricerca
Pubblicazioni Recenti
2022
|
Cardano M; Buscemi G; Zannini L Sex disparities in DNA damage response pathways: Novel determinants in cancer formation and therapy Journal Article In: iScience, vol. 25, iss. 3, pp. 103875, 2022. @article{%a1.%Ybq,
title = {Sex disparities in DNA damage response pathways: Novel determinants in cancer formation and therapy},
author = {Cardano M and Buscemi G and Zannini L},
url = {https://www.sciencedirect.com/science/article/pii/S2589004222001456?via%3Dihub},
doi = {10.1016/j.isci.2022.103875},
year = {2022},
date = {2022-05-30},
journal = {iScience},
volume = {25},
issue = {3},
pages = {103875},
abstract = {Cancer incidence and survival are different between men and women. Indeed, females have a lesser risk and a better prognosis than males in many tumors unrelated to reproductive functions. Although the reasons for these disparities are still unknown, they constitute an important starting point for the development of personalized cancer therapies. One of the mechanisms that fuels carcinogenesis is the accumulation of defects in DNA damage response (DDR) pathways, a complex signaling cascade that senses DNA lesions and, depending on the severity, coordinates transient cell-cycle arrest, DNA replication, repair, apoptosis, and senescence, preventing genomic instability and cancer. Recently, evidence of sexual dimorphisms is emerging in these pathways, therefore providing new opportunities for precision medicine. Here, we will discuss current knowledge about sexual disparities in the DDR, their role in tumorigenesis and cancer progression, and the importance of considering sex contribution in both research and cancer therapies.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Cancer incidence and survival are different between men and women. Indeed, females have a lesser risk and a better prognosis than males in many tumors unrelated to reproductive functions. Although the reasons for these disparities are still unknown, they constitute an important starting point for the development of personalized cancer therapies. One of the mechanisms that fuels carcinogenesis is the accumulation of defects in DNA damage response (DDR) pathways, a complex signaling cascade that senses DNA lesions and, depending on the severity, coordinates transient cell-cycle arrest, DNA replication, repair, apoptosis, and senescence, preventing genomic instability and cancer. Recently, evidence of sexual dimorphisms is emerging in these pathways, therefore providing new opportunities for precision medicine. Here, we will discuss current knowledge about sexual disparities in the DDR, their role in tumorigenesis and cancer progression, and the importance of considering sex contribution in both research and cancer therapies. |
2019
|
Magni M; Buscemi G; Maita L; Peng L; Chan SY; Montecucco A; Delia D; Zannini L TSPYL2 is a novel regulator of SIRT1 and p300 activity in response to DNA damage. Journal Article In: Cell death and differentiation, vol. 26, no. 5, pp. 918-931, 2019. @article{%a1:%Y_79,
title = {TSPYL2 is a novel regulator of SIRT1 and p300 activity in response to DNA damage.},
author = {Magni M and Buscemi G and Maita L and Peng L and Chan SY and Montecucco A and Delia D and Zannini L},
url = {https://www.nature.com/articles/s41418-018-0168-6},
doi = {10.1038/s41418-018-0168-6},
year = {2019},
date = {2019-03-06},
journal = {Cell death and differentiation},
volume = {26},
number = {5},
pages = {918-931},
abstract = {Protein acetylation and deacetylation events are finely regulated by lysine-acetyl-transferases and lysine-deacetylases and constitute an important tool for the activation or inhibition of specific cellular pathways. One of the most important lysine-acetyl-transferases is p300, which is involved in the regulation of gene expression, cell growth, DNA repair, differentiation, apoptosis, and tumorigenesis. A well-known target of p300 is constituted by the tumor suppressor protein p53, which plays a critical role in the maintenance of genomic stability and whose activity is known to be controlled by post-translational modifications, among which acetylation. p300 activity toward p53 is negatively regulated by the NAD-dependent deacetylase SIRT1, which deacetylates p53 preventing its transcriptional activation and the induction of p53-dependent apoptosis. However, the mechanisms responsible for p53 regulation by p300 and SIRT1 are still poorly understood. Here we identify the nucleosome assembly protein TSPY-Like 2 (TSPYL2, also known as TSPX, DENTT, and CDA1) as a novel regulator of SIRT1 and p300 function. We demonstrate that, upon DNA damage, TSPYL2 inhibits SIRT1, disrupting its association with target proteins, and promotes p300 acetylation and activation, finally stimulating p53 acetylation and p53-dependent cell death. Indeed, in response to DNA damage, cells silenced for TSPYL2 were found to be defective in p53 activation and apoptosis induction and these events were shown to be dependent on SIRT1 and p300 function. Collectively, our results shed new light on the regulation of p53 acetylation and activation and reveal a novel TSPYL2 function with important implications in cancerogenesis.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Protein acetylation and deacetylation events are finely regulated by lysine-acetyl-transferases and lysine-deacetylases and constitute an important tool for the activation or inhibition of specific cellular pathways. One of the most important lysine-acetyl-transferases is p300, which is involved in the regulation of gene expression, cell growth, DNA repair, differentiation, apoptosis, and tumorigenesis. A well-known target of p300 is constituted by the tumor suppressor protein p53, which plays a critical role in the maintenance of genomic stability and whose activity is known to be controlled by post-translational modifications, among which acetylation. p300 activity toward p53 is negatively regulated by the NAD-dependent deacetylase SIRT1, which deacetylates p53 preventing its transcriptional activation and the induction of p53-dependent apoptosis. However, the mechanisms responsible for p53 regulation by p300 and SIRT1 are still poorly understood. Here we identify the nucleosome assembly protein TSPY-Like 2 (TSPYL2, also known as TSPX, DENTT, and CDA1) as a novel regulator of SIRT1 and p300 function. We demonstrate that, upon DNA damage, TSPYL2 inhibits SIRT1, disrupting its association with target proteins, and promotes p300 acetylation and activation, finally stimulating p53 acetylation and p53-dependent cell death. Indeed, in response to DNA damage, cells silenced for TSPYL2 were found to be defective in p53 activation and apoptosis induction and these events were shown to be dependent on SIRT1 and p300 function. Collectively, our results shed new light on the regulation of p53 acetylation and activation and reveal a novel TSPYL2 function with important implications in cancerogenesis. |
2018
|
Magni M; Buscemi G; Zannini L Cell cycle and apoptosis regulator 2 at the interface between DNA damage response and cell physiology Journal Article In: Mutation research - Reviews in Mutation Research, vol. 776, pp. 1-9, 2018. @article{%a1:%Y_154,
title = {Cell cycle and apoptosis regulator 2 at the interface between DNA damage response and cell physiology},
author = {Magni M and Buscemi G and Zannini L},
url = {https://www.sciencedirect.com/science/article/pii/S1383574218300073?via%3Dihub},
doi = {10.1016/j.mrrev.2018.03.004},
year = {2018},
date = {2018-02-14},
journal = {Mutation research - Reviews in Mutation Research},
volume = {776},
pages = {1-9},
abstract = {Cell cycle and apoptosis regulator 2 (CCAR2 or DBC1) is a human protein recently emerged as a novel and important player of the DNA damage response (DDR). Indeed, upon genotoxic stress, CCAR2, phosphorylated by the apical DDR kinases ATM and ATR, increases its binding to the NAD+-dependent histone deacetylase SIRT1 and inhibits SIRT1 activity. This event promotes the acetylation and activation of p53, a SIRT1 target, and the subsequent induction of p53 dependent apoptosis. In addition, CCAR2 influences DNA repair pathway choice and promotes the chromatin relaxation necessary for the repair of heterochromatic DNA lesions. However, besides DDR, CCAR2 is involved in several other cellular functions. Indeed, through the interaction with transcription factors, nuclear receptors, epigenetic modifiers and RNA polymerase II, CCAR2 regulates transcription and transcript elongation. Moreover, promoting Rev-erbα protein stability and repressing BMAL1 and CLOCK expression, it was reported to modulate the circadian rhythm. Through SIRT1 inhibition, CCAR2 is also involved in metabolism control and, suppressing RelB and p65 activities in the NFkB pathway, it restricts B cell proliferation and immunoglobulin production. Notably, CCAR2 expression is deregulated in several tumors and, compared to the non-neoplastic counterpart, it may be up- or down-regulated. Since its up-regulation in cancer patients is usually associated with poor prognosis and its depletion reduces cancer cell growth in vitro, CCAR2 was suggested to act as a tumor promoter. However, there is also evidence that CCAR2 functions as a tumor suppressor and therefore its role in cancer formation and progression is still unclear. In this review we discuss CCAR2 functions in the DDR and its multiple biological activities in unstressed cells.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Cell cycle and apoptosis regulator 2 (CCAR2 or DBC1) is a human protein recently emerged as a novel and important player of the DNA damage response (DDR). Indeed, upon genotoxic stress, CCAR2, phosphorylated by the apical DDR kinases ATM and ATR, increases its binding to the NAD+-dependent histone deacetylase SIRT1 and inhibits SIRT1 activity. This event promotes the acetylation and activation of p53, a SIRT1 target, and the subsequent induction of p53 dependent apoptosis. In addition, CCAR2 influences DNA repair pathway choice and promotes the chromatin relaxation necessary for the repair of heterochromatic DNA lesions. However, besides DDR, CCAR2 is involved in several other cellular functions. Indeed, through the interaction with transcription factors, nuclear receptors, epigenetic modifiers and RNA polymerase II, CCAR2 regulates transcription and transcript elongation. Moreover, promoting Rev-erbα protein stability and repressing BMAL1 and CLOCK expression, it was reported to modulate the circadian rhythm. Through SIRT1 inhibition, CCAR2 is also involved in metabolism control and, suppressing RelB and p65 activities in the NFkB pathway, it restricts B cell proliferation and immunoglobulin production. Notably, CCAR2 expression is deregulated in several tumors and, compared to the non-neoplastic counterpart, it may be up- or down-regulated. Since its up-regulation in cancer patients is usually associated with poor prognosis and its depletion reduces cancer cell growth in vitro, CCAR2 was suggested to act as a tumor promoter. However, there is also evidence that CCAR2 functions as a tumor suppressor and therefore its role in cancer formation and progression is still unclear. In this review we discuss CCAR2 functions in the DDR and its multiple biological activities in unstressed cells. |