This proposal is designed to test the overall hypothesis that reconstitution of C18-ceramide generation mediates lethal autophagy, subsequently leading to mitochondrial dysfunction, and suppression of HNSCC tumor growth. As a corollary, the hypothesis that treatment of HNSCCs with C18-ceramide analogues, such as C18-pyridinium-ceramide (C18-Pyr-Cer), which enhance LC3-lipidation and mitochondrial targeting, induces autophagy-mediated tumor suppression will also be tested. To test these novel hypotheses, three Specific Aims are proposed:
Specific Aim 1. Determine the roles of CerS1-generated C18-(dihydro)ceramide in the regulation of HNSCC growth inhibition via induction of autophagy.
Specific Aim 2. Define the down-stream mechanisms by which CerS1/C18-ceramide signaling induces lethal autophagy.
Specific Aim 3. Define the roles of C18-ceramide and LC3-II in selective mitochondrial targeting of autophagosomes to enhance lethal autophagy and tumor suppression. Collectively, studies proposed in this application will help define novel mechanisms involved selectively in the regulation of lethal autophagy by C18-ceramide signaling, which subsequently leads to suppression of HNSCC tumor growth.
Because novel strategies are needed for the treatment of human head and neck squamous cell carcinoma (HNSCC), the long-term objective of this proposal is to develop mechanism based therapeutic strategies for the treatment of this disease. To this end, these proposed studies will identify novel mechanisms by which C18- ceramide selectively induces lethal autophagy, leading to the suppression of HNSCC tumor growth. Data obtained from these studies will also help resolve the autophagy paradox, and define checkpoint mechanisms involved in inducing lethal versus survival autophagy by ceramide signaling, which will lead to the development of novel therapeutics against HNSCC.
|Panneer Selvam, Shanmugam; Roth, Braden M; Nganga, Rose et al. (2018) Balance between senescence and apoptosis is regulated by telomere damage-induced association between p16 and caspase-3. J Biol Chem 293:9784-9800|
|Ramshesh, Venkat K; Lemasters, John J (2018) Imaging of Mitochondrial pH Using SNARF-1. Methods Mol Biol 1782:351-356|
|Ogretmen, Besim (2018) Sphingolipid metabolism in cancer signalling and therapy. Nat Rev Cancer 18:33-50|
|Gencer, Salih; Oleinik, Natalia; Kim, Jisun et al. (2017) TGF-? receptor I/II trafficking and signaling at primary cilia are inhibited by ceramide to attenuate cell migration and tumor metastasis. Sci Signal 10:|
|Lemasters, John J (2017) Evolution of Voltage-Dependent Anion Channel Function: From Molecular Sieve to Governator to Actuator of Ferroptosis. Front Oncol 7:303|
|Lv, Zongyang; Rickman, Kimberly A; Yuan, Lingmin et al. (2017) S. pombe Uba1-Ubc15 Structure Reveals a Novel Regulatory Mechanism of Ubiquitin E2 Activity. Mol Cell 65:699-714.e6|
|Thomas, Raquela J; Oleinik, Natalia; Panneer Selvam, Shanmugam et al. (2017) HPV/E7 induces chemotherapy-mediated tumor suppression by ceramide-dependent mitophagy. EMBO Mol Med 9:1030-1051|
|Dany, Mohammed; Gencer, Salih; Nganga, Rose et al. (2016) Targeting FLT3-ITD signaling mediates ceramide-dependent mitophagy and attenuates drug resistance in AML. Blood 128:1944-1958|
|Dany, Mohammed; Ogretmen, Besim (2015) Ceramide induced mitophagy and tumor suppression. Biochim Biophys Acta 1853:2834-45|
|Tirodkar, Tejas S; Lu, Ping; Bai, Aiping et al. (2015) Expression of Ceramide Synthase 6 Transcriptionally Activates Acid Ceramidase in a c-Jun N-terminal Kinase (JNK)-dependent Manner. J Biol Chem 290:13157-67|
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