SOD2 confers anlotinib resistance via regulation of mitochondrial damage in OSCC

METTL3 inhibitor STM2457 impairs tumor progression and enhances sensitivity to anlotinib in OSCC

OBJECTIVES

To investigate the inhibitory effects of STM2457, which is a novel METTL3 (m6 A writer) inhibitor, both as a monotherapy and in combination with anlotinib, in the treatment of oral squamous cell carcinoma (OSCC) both in vitro and in vivo.

MATERIALS AND METHODS

The efficacy of STM2457 or STM2457 plus anlotinib was evaluated using two OSCC cell lines by CCK8, transwell, colony formation, would-healing, sphere formation, cell cycle, apoptosis assays, and nude mice tumor xenograft techniques. The molecular mechanism study was carried out by western blotting, qRT-PCR, MeRIP-qPCR, immunofluorescence, and immunohistochemistry.

RESULTS

STM2457 combined with anlotinib enhanced inhibition of cellular survival/proliferation and promotion of apoptosis in vitro. Moreover, this combinatorial approach exerted a notable reduction in stemness properties and EMT (epithelial-mesenchymal transition) features of OSCC cells. Remarkably, in vivo studies validated the efficacy of the combination treatment. Mechanistically, our investigations revealed that the combined action of STM2457 and anlotinib exerted downregulatory effects on EGFR (epidermal growth factor receptor) expression in OSCC cells.

CONCLUSIONS

The combination of STM2457 and anlotinib targeting EGFR exerted a multiple anti-tumor effect. In near future, anlotinib combined with STM2457 may provide a novel insight for the treatment of OSCC.

Efficacy and Safety of Anlotinib-Containing Regimens in Advanced Non-Small Cell Lung Cancer: A Real-World Study

Purpose

Anlotinib is widely used in the clinical treatment of non-small cell lung cancer (NSCLC), alone or in combination with other anticancer drugs. The aim of this study was to investigate the real-world efficacy and safety of anlotinib-containing regimens.

Patients and Methods

Confirmed advanced NSCLC patients who had received anlotinib alone or in combination were enrolled. An overall analysis of the efficacy and safety of anlotinib was performed in all patients, and then subgroup analysis was used to further compare the efficacy between anlotinib monotherapy and combination therapy. The primary endpoint was progression-free survival (PFS), and the secondary endpoints were ADR, ORR, and DCR.

Results

A total of 240 patients were included. The overall median PFS was 8.5 months (95% confidence interval [CI]: 7.1-9.9 months). Anlotinib treatment regimens (monotherapy or combination therapy) and whether they received previous antiangiogenesis were associated with PFS. Anlotinib plus immunotherapy achieved longer PFS than anlotinib monotherapy (median PFS: 10.5 vs 6.5 months, p=0.007). Stratification analysis showed the PFS of anlotinib plus immunotherapy was significantly longer in male, adenocarcinoma, <=65 years old, patients stage IV, EGFR wild type, with extrathoracic metastasis, performance status scores ≥2, the first-line treatment, patients with a history of hypertension and no previous antiangiogenesis than anlotinib monotherapy. The median PFS of anlotinib plus chemotherapy, targeted therapy was slightly longer than anlotinib alone (respectively, 10.5 vs 6.5 months, p=0.095; 9.5 vs 6.5 months, p=0.177). Adverse reactions were mostly mild and acceptable, with hypertension being the most common.

Conclusion

Anlotinib is effective and tolerable in advanced NSCLC patients. Immunotherapy combination with anlotinib significantly improved PFS. The efficacy of anlotinib may be impaired by previous antiangiogenic therapy, which can be investigated in further studies.

Interaction between Cigarette Smoke and Human Papillomavirus 16 E6/E7 Oncoproteins to Induce SOD2 Expression and DNA Damage in Head and Neck Cancer

Even though epidemiological studies suggest that tobacco smoking and high-risk human papillomavirus (HR-HPV) infection are mutually exclusive risk factors for developing head and neck cancer (HNC), a portion of subjects who develop this heterogeneous group of cancers are both HPV-positive and smokers. Both carcinogenic factors are associated with increased oxidative stress (OS) and DNA damage. It has been suggested that superoxide dismutase 2 (SOD2) can be independently regulated by cigarette smoke and HPV, increasing adaptation to OS and tumor progression. In this study, we analyzed SOD2 levels and DNA damage in oral cells ectopically expressing HPV16 E6/E7 oncoproteins and exposed to cigarette smoke condensate (CSC). Additionally, we analyzed SOD2 transcripts in The Cancer Genome Atlas (TCGA) Head and Neck Cancer Database. We found that oral cells expressing HPV16 E6/E7 oncoproteins exposed to CSC synergistically increased SOD2 levels and DNA damage. Additionally, the SOD2 regulation by E6, occurs in an Akt1 and ATM-independent manner. This study suggests that HPV and cigarette smoke interaction in HNC promotes SOD2 alterations, leading to increased DNA damage and, in turn, contributing to development of a different clinical entity.