vx-970 and Squamous-Cell-Carcinoma-of-Head-and-Neck

The study aimed to assess the effect of p-ATR inhibitor VE-822 in the combination chemotherapy with cisplatin of head and neck squamous cell carcinoma and to explore the possible mechanism.. The DNA damage levels were determined by comet assay and western blot experiments in cisplatin-resistant and sensitive cell lines. The IC50 value changes after combination treatment with VE-822 in cisplatin sensitive and resistant cell lines were detected by the CCK-8 test. The effects of VE-822 combined with cisplatin on proliferation ability, colony formation ability, migration ability, cell apoptosis and cell cycle changes were observed. The increased expression of the p-ATR protein was related to the DNA damage repair pathway in head and neck squamous cell carcinoma cisplatin-resistant cells. VE-822 inhibited cell proliferation, colony formation and migration abilities and improved the cisplatin chemotherapeutic effects in subcutaneous xenograft models of nude mice by inhibiting the p-ATR expression and blocking DNA damage repair pathway.. The p-ATR expression increased in head and neck squamous cell carcinoma cisplatinresistant cells. VE-822 significantly enhanced the therapeutic effect in cisplatin resistant head and neck squamous cell carcinoma by inhibiting p-ATR expression

Topics: Animals; Antineoplastic Agents; Apoptosis; Carcinoma, Squamous Cell; Cell Line, Tumor; Cisplatin; Head and Neck Neoplasms; Humans; Mice; Mice, Nude; Squamous Cell Carcinoma of Head and Neck

Alterations in the DNA damage response play a crucial role in radio- and chemoresistance of neoplastic cells. Activation of the Ataxia telangiectasia and Rad3-related (ATR) pathway is an important DNA damage response mechanism in head and neck squamous cell carcinoma (HNSCC). Berzosertib, a selective ATR inhibitor, shows promising radio- and chemosensitizing effects in preclinical studies and is well tolerated in clinical studies. The aim of this study was to elucidate the effect of berzosertib treatment in combination with radiation and cisplatin in HNSCC. The HNSCC cell lines Cal-27 and FaDu were treated with berzosertib alone and in combination with radiation or cisplatin. Cell viability and clonogenic survival were evaluated. The effect of combination treatment was evaluated with the SynergyFinder or combination index. Apoptosis was assessed via measurement of caspase 3/7 activation and migration was evaluated using a wound healing assay. Berzosertib treatment decreased cell viability in a dose-dependent manner and increased apoptosis. The IC

Topics: Apoptosis; Ataxia Telangiectasia Mutated Proteins; Cell Line; Cell Line, Tumor; Cisplatin; Head and Neck Neoplasms; Humans; Squamous Cell Carcinoma of Head and Neck

DNA damage response inhibitors (DDRi) may selectively enhance the inactivation of tumor cells in combination with ionizing radiation (IR). The induction of senescence may be the key mechanism of tumor cell inactivation in this combinatorial treatment. In the current study the effect of combined IR with DDRi on the induction of senescence was studied in head and neck squamous cell carcinoma (HNSCC) cells with different human papilloma virus (HPV) status. The integrity of homologous recombination (HR) was assessed in two HPV positive, two HPV negative HNSCC, and two healthy fibroblast cell cultures. Cells were treated with the DDRi CC-115 (DNA-dependent protein kinase, DNA-pK; dual mammalian target of rapamycin, mTor), VE-822 (ATR; ataxia telangiectasia and Rad3-related kinase), and AZD0156 (ATM; ataxia telangiectasia mutated kinase) combined with IR. Effects on senescence, apoptosis, necrosis, and cell cycle were analyzed by flow cytometry. The fibroblast cell lines generally tolerated IR or combined treatment better than the tumor cell lines. The ATM and ATR inhibitors were effectively inducing senescence when combined with IR. The DNA-PK inhibitor was not an important inductor of senescence. HPV status and HR activity had a limited influence on the efficacy of DDRi. Induction of senescence and necrosis varied individually among the cell lines due to molecular heterogeneity and the involvement of DNA damage response pathways in senescence induction.

Topics: Apoptosis; Ataxia Telangiectasia Mutated Proteins; Cell Cycle; Cell Line, Tumor; Cellular Senescence; DNA Damage; Fibroblasts; Head and Neck Neoplasms; Humans; Isoxazoles; Male; Protein Kinase Inhibitors; Pyrazines; Pyridines; Quinolines; Radiation, Ionizing; Signal Transduction; Squamous Cell Carcinoma of Head and Neck; TOR Serine-Threonine Kinases; Triazoles