We are interested in the molecular mechanisms of cell senescence, which is considered as an irreversible arrest of cell proliferation involved in normal and pathological ageing of the organism. Senescent cells remain alive and metabolically active. They secrete a mix of molecules which can influence other cells. We are interested whether these molecules are secreted in exosomes and how they change the function of the immune cells. Senescent cells can also communicate with other cells by cytoplasmic bridges which are of our interest. We study the mechanisms of cell autophagy and its molecular and functional connection with cell senescence. DNA double strand breaks (DSBs) triggers a signaling and effector pathway known as the DNA damage response (DDR) that coordinates cell-cycle arrest and DNA repair. It is believed that persistent DDR signaling establishes cellular senescence. Our studies indicate that this paradigm is not valid in some models of cell senescence. Moreover, ATM the key protein of DDR can still have unrecognized role in DDR-independent senescence as well as senescence of non-dividing post-mitotic (neuronal) cells. In senescing human VSMCs we aim to dissect the role of epigenetic modiﬁcation and compaction of chromatin. Cell senescence can be also induced in cancer cells as an outcome of anticancer treatment. As we showed previously that the process of cancer cell senescence can be reversible we are interested in dissecting the mechanisms of divisions of cancer cells induced to senescence and the role of polyploidy and stemness in this process.
The projects are aimed to dissect:
- the role of senescence induced secretory phenotype (SIPS) of senescing human vascular smooth muscle cells (VSMCs) in modulating of the immune cell function,
- the role of chromatin modulation in normal cell senescence ( VSMCs, human skin fibroblasts),
- the role of cytoskeletal proteins in direct communication between human senescent cells (VSMCs),
- the influence of natural polyphenol, curcumin on DNA damage and its role in senescence of normal and cancer cells,
- the role of DNA damage and DNA damage response (DDR) in senescence, autophagy and cell death of rodent neurons and human iPSCs,
- mechanisms of cell senescence and induction of secretory phenotype in cancer cells with non-functional DDR, particularly due to the lack of the functional p53 protein,
- the interconnection between senescence, polyploidy and stemness of cancer cells,
- the mechanisms of autophagy regulation by tacrin- -melatonin derivatives in normal and cancer cells,
- the role of the immune system and inﬂammaging in healthy and unhealthy ageing,
- the inﬂuence of novel agents targeting telomeres on cancer and normal cell fate.
Kucharewicz K, Dudkowska M, Zawadzka A, Ogrodnik M, Szczepankiewicz AA, Czarnocki Z, Sikora E. Simultaneous induction and blockade of autophagy by a single agent. Cell Death Dis. 2018 Mar 2;9(3):353.
Strzeszewska A, Alster O, Mosieniak G, Ciolko A, Sikora E. Insight into the role of PIKK family members and NF-кB in DNAdamage-induced senescence and senescence-associated secretory phenotype of colon cancer cells. Cell Death Dis. 2018 Jan 19;9(2):44
Piechota M, Sunderland P, Wysocka A, Nalberczak M, Sliwinska MA, Radwanska K, Sikora E. Is senescence-associated β-galactosidase a marker of neuronal senescence? Oncotarget. 2016 Dec 6;7(49):81099-81109.
Grabowska W, Suszek M, Wnuk M, Lewinska A, Wasiak E, Sikora E, Bielak-Zmijewska A. Curcumin elevates sirtuin level but does not postpone in vitro senescence of human cells building the vasculature. Oncotarget. 2016 Apr 12;7(15):19201-13.
Mosieniak G, Sliwinska MA, Alster O, Strzeszewska A, Sunderland P, Piechota M, Was H, Sikora E. Polyploidy Formation in Doxorubicin-Treated Cancer Cells Can Favor Escape from Senescence. Neoplasia. 2015 Dec;17(12):882-93.