Giacomo Buscemi
Istituto di Genetica Molecolare “Luigi Luca Cavalli-Sforza” – CNR
Via Abbiategrasso, 207
27100 Pavia
Tel: 0382 546327
E-mail: giacomo.buscemi@igm.cnr.it
Curriculum Vitae – Download
Elenco completo delle pubblicazioni – Download
Attività di ricerca
Il DNA contenuto nel nucleo delle nostre cellule è per sua natura sotto il costante attacco di agenti fisici e chimici. Fattori interni, come i radicali liberi prodotti dal normale metabolismo cellulare, e fattori esterni, come i raggi ultravioletti del sole o sostanze chimiche presenti nell’inquinamento atmosferico, nei cibi industriali o nel fumo, sono in grado di modificare la struttura del DNA. In condizioni normali ognuna delle cellule del nostro corpo è colpita, riconosce e ripara ogni giorno decine di migliaia di lesioni al DNA, preservando l’originale informazione genetica da trasmettere alle cellule figlie. Dalla capacità di mantenere l’integrità del genoma dipende il destino delle cellule, infatti difetti nella risposta al danno al DNA e nella sua riparazione possono causare quell’instabilità genomica che, per esempio, facilita la loro trasformazione in cellule tumorali. A conferma di ciò, diverse malattie genetiche, alcune rare altre più comuni, spesso caratterizzate da predisposizione all’insorgenza di tumori sono causate da difetti nei geni coinvolti nella risposta al danno.
Questa risposta nelle cellule umane è molto complessa e può arrivare a coinvolgere centinaia di proteine. Sono noti diversi fattori della risposta al danno e dei processi di riparazione del DNA, tuttavia, in molti casi, la loro funzione biochimica è poco chiara.
Nel suo complesso i miei studi hanno lo scopo di dissezionare meccanismi molecolari della risposta al danno al DNA, rilevanti per il mantenimento della stabilità del genoma, identificando possibili marcatori ma anche target per un approccio terapeutico il più possibile mirato di tumori o di malattie genetiche rare.
In passato, studiando malattie come l’Atassia Telangiectasia o la Sindrome da rotture cromosomiche di Nijmegen, ho identificato in cellule umane nuovi meccanismi molecolari nel sistema di segnalazione della presenza di rotture di entrambi i filamenti del DNA. La sottile modulazione di questi meccanismi nella cellula decide in che modo riparare ogni lesione, se è necessario arrestare transitoriamente il ciclo cellulare per non peggiorare il danno, se serve indurre un invecchiamento cellulare precoce o persino programmare il suicidio cellulare piuttosto che passare alle cellule figlie un genoma modificato, rischiando così di far insorgere una malattia letale per l’organismo. Ho anche studiato alcuni aspetti della protezione dei telomeri che evitano che le estremità dei cromosomi vengano riconosciute e trattate come rotture del DNA, prevenendo attività di riparazione indesiderate che possono condurre a fusione di cromosomi.
Attualmente, in collaborazione con altri laboratori sia dell’IGM-CNR che dell’Università degli Studi di Milano e di Bari, mi sto occupando dell’analisi dettagliata dei meccanismi che regolano la scelta di come riparare i DSBs a seconda del contesto cromatinico e trascrizionale in cui accadono. Sto studiando in particolare il ruolo dei prodotti dei geni BRCA1 e BRCA2, noti per essere mutati nel tumore ereditario al seno e del gene SETX, le cui mutazioni causano l’Aprassia Oculomotoria di tipo 2 (AOA2) e una forma rara di Sclerosi Laterale Amiotrofica giovanile.
Progetti di ricerca
Pubblicazioni Recenti
2023
|
Cardano M; Magni M; Alfieri R; Chan SY; Sabbioneda S; Buscemi G; Zannini L Sex specific regulation of TSPY-Like 2 in the DNA damage response of cancer cells Journal Article In: Cell death and disease, vol. 14, iss. 3, pp. 197, 2023. @article{%a1.%Yb_68,
title = {Sex specific regulation of TSPY-Like 2 in the DNA damage response of cancer cells},
author = {Cardano M and Magni M and Alfieri R and Chan SY and Sabbioneda S and Buscemi G and Zannini L},
url = {https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10015022/},
doi = {10.1038/s41419-023-05722-2},
year = {2023},
date = {2023-03-01},
journal = {Cell death and disease},
volume = {14},
issue = {3},
pages = {197},
abstract = {Females have a lower probability to develop somatic cancers and a better response to chemotherapy than males. However, the reasons for these differences are still not well understood. The X-linked gene TSPY-Like 2 (TSPYL2) encodes for a putative tumor suppressor protein involved in cell cycle regulation and DNA damage response (DDR) pathways. Here, we demonstrate that in unstressed conditions TSPYL2 is maintained at low levels by MDM2-dependent ubiquitination and proteasome degradation. Upon genotoxic stress, E2F1 promotes TSPYL2 expression and protein accumulation in non-transformed cell lines. Conversely, in cancer cells, TSPYL2 accumulates only in females or in those male cancer cells that lost the Y-chromosome during the oncogenic process. Hence, we demonstrate that while TSPYL2 mRNA is induced in all the tested tumor cell lines after DNA damage, TSPYL2 protein stability is increased only in female cancer cells. Indeed, we found that TSPYL2 accumulation, in male cancer cells, is prevented by the Y-encoded protein SRY, which modulates MDM2 protein levels. In addition, we demonstrated that TSPYL2 accumulation is required to sustain cell growth arrest after DNA damage, possibly contributing to protect normal and female cancer cells from tumor progression. Accordingly, TSPYL2 has been found more frequently mutated in female-specific cancers. These findings demonstrate for the first time a sex-specific regulation of TSPYL2 in the DDR of cancer cells and confirm the existence of sexual dimorphism in DNA surveillance pathways.},
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pubstate = {published},
tppubtype = {article}
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Females have a lower probability to develop somatic cancers and a better response to chemotherapy than males. However, the reasons for these differences are still not well understood. The X-linked gene TSPY-Like 2 (TSPYL2) encodes for a putative tumor suppressor protein involved in cell cycle regulation and DNA damage response (DDR) pathways. Here, we demonstrate that in unstressed conditions TSPYL2 is maintained at low levels by MDM2-dependent ubiquitination and proteasome degradation. Upon genotoxic stress, E2F1 promotes TSPYL2 expression and protein accumulation in non-transformed cell lines. Conversely, in cancer cells, TSPYL2 accumulates only in females or in those male cancer cells that lost the Y-chromosome during the oncogenic process. Hence, we demonstrate that while TSPYL2 mRNA is induced in all the tested tumor cell lines after DNA damage, TSPYL2 protein stability is increased only in female cancer cells. Indeed, we found that TSPYL2 accumulation, in male cancer cells, is prevented by the Y-encoded protein SRY, which modulates MDM2 protein levels. In addition, we demonstrated that TSPYL2 accumulation is required to sustain cell growth arrest after DNA damage, possibly contributing to protect normal and female cancer cells from tumor progression. Accordingly, TSPYL2 has been found more frequently mutated in female-specific cancers. These findings demonstrate for the first time a sex-specific regulation of TSPYL2 in the DDR of cancer cells and confirm the existence of sexual dimorphism in DNA surveillance pathways. |
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. |
2020
|
Sanese P; Fasano C; Buscemi G; Bottino C; Corbetta S; Fabini E; Silvestri V; Valentini V; Disciglio V; Forte G; Lepore Signorile M; De Marco K; Bertora S; Grossi V; Guven U; Porta N; Di Maio V; Manoni E; Giannelli G; Bartolini M; Del Rio A; Caretti G; Ottini L; Simone C Targeting SMYD3 to Sensitize Homologous Recombination-Proficient Tumors to PARP-Mediated Synthetic Lethality. Journal Article In: iScience, vol. 23, no 10, pp. 101604, 2020. @article{%a1:%Y_474,
title = {Targeting SMYD3 to Sensitize Homologous Recombination-Proficient Tumors to PARP-Mediated Synthetic Lethality. },
author = {Sanese P and Fasano C and Buscemi G and Bottino C and Corbetta S and Fabini E and Silvestri V and Valentini V and Disciglio V and Forte G and Lepore Signorile M and De Marco K and Bertora S and Grossi V and Guven U and Porta N and Di Maio V and Manoni E and Giannelli G and Bartolini M and {Del Rio A} and Caretti G and Ottini L and Simone C},
url = {https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7648160/},
doi = {10.1016/j.isci.2020.101604},
year = {2020},
date = {2020-01-01},
journal = {iScience},
volume = {23},
number = {10},
pages = {101604},
abstract = {SMYD3 is frequently overexpressed in a wide variety of cancers. Indeed, its inactivation reduces tumor growth in preclinical in vivo animal models. However, extensive characterization in vitro failed to clarify SMYD3 function in cancer cells, although confirming its importance in carcinogenesis. Taking advantage of a SMYD3 mutant variant identified in a high-risk breast cancer family, here we show that SMYD3 phosphorylation by ATM enables the formation of a multiprotein complex including ATM, SMYD3, CHK2, and BRCA2, which is required for the final loading of RAD51 at DNA double-strand break sites and completion of homologous recombination (HR). Remarkably, SMYD3 pharmacological inhibition sensitizes HR-proficient cancer cells to PARP inhibitors, thereby extending the potential of the synthetic lethality approach in human tumors.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
SMYD3 is frequently overexpressed in a wide variety of cancers. Indeed, its inactivation reduces tumor growth in preclinical in vivo animal models. However, extensive characterization in vitro failed to clarify SMYD3 function in cancer cells, although confirming its importance in carcinogenesis. Taking advantage of a SMYD3 mutant variant identified in a high-risk breast cancer family, here we show that SMYD3 phosphorylation by ATM enables the formation of a multiprotein complex including ATM, SMYD3, CHK2, and BRCA2, which is required for the final loading of RAD51 at DNA double-strand break sites and completion of homologous recombination (HR). Remarkably, SMYD3 pharmacological inhibition sensitizes HR-proficient cancer cells to PARP inhibitors, thereby extending the potential of the synthetic lethality approach in human tumors. |
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. |
