Temozolomide-perillyl alcohol conjugate (NEO212), a novel temozolomide (TMZ) analog, was previously reported to exert its anti-cancer effect in non-small cell lung cancer (NSCLC), and human nasopharyngeal carcinoma (NPC), etc.. In the current study, we intend to illuminate the potential anticancer property and the underly mechanisms of NEO212 in ovarian cancer cells. The cytotoxicity of NEO212 was detected by MTT, colony formation analysis and xenograft model. The proteins involved in cell proliferation, DNA damage, autophagy and lysosomal function were detected by western blots; mitochondria, lysosome and autophagosome were visualized by TEM and/or immunofluorescence; Apoptosis, cell cycle analysis and mitochondrial transmembrane potential were detected by flow cytometry. TFEB translocation was detected by immunofluorescence and western blot. NEO212 has the potential anticancer property in ovarian cancer cells, as evidence from cell proliferation inhibition, G2/M arrest, DNA damage, xenograft, mitochondrial dysfunction and apoptosis. Importantly, we observed that although it induced significant accumulation of autophagosomes, NEO212 quenched GFP-LC3 degradation, down-regulated a series of lysosome related gene expression and blocked the autophagic flux, which significantly facilitated it induced apoptosis and was largely because it inhibited the nuclear translocation of transcription factor EB (EB). NEO212 inhibited TFEB translocation, and impaired the lysosomal function, implying NEO212 might avoid from autophagy mediated chemo-resistance, thus proposing NEO212 as a potential therapeutic candidate for ovarian cancer.

Temozolomide-perillyl alcohol conjugate (TMZ-POH), a novel Temozolomide (TMZ) analog developed based on the conjugation of TMZ and perillyl alcohol (POH), displayed strong anticancer potency in multiple cancer types. In this study, we aimed to clarify the relationship between TMZ-POH and autophagy, and explore the underlying mechanisms involved in. The proteins involved in autophagy, mitochondrial fission, lysosomal function and membrane traffic were detected by western blots; Autophagosome, mitochondria and lysosome were visualized by transmission electron microscope (TEM) and immunostaining; Apoptosis analysis and fluorescence probe detection were applied by flow cytometry. TMZ-POH blocked mitophagy flux although the number of autophagosomes which colocalized with mitochondria in the cells was increased via inducing lysosomal dysfunction as evidence from impaired lysosomal acidification, maturation and hampered autophagosome- lysosome fusion, which largely depended on its downregulation on the small GTPase RAB7A via mevalonate pathway. More importantly, our data demonstrated TMZ-POH sensitized cancer cell to irradiation induced apoptosis. Temozolomide-perillyl alcohol conjugate impairs mitophagy flux by inducing lysosomal dysfunction in Non-Small Cell Lung Cancer (NSCLC) cells and sensitizes them to irradiation, thereby proposing TMZ-POH as a potential radiosensitizer.

Liensinine is a bioactive component of Plumula Nelumbinis extracted from the green embryo of the mature seeds of Nelumbonaceae and exhibits therapeutic functions and noteworthy anti-tumor effects in recent studies. However, the potential anti-tumor property and the underlying mechanisms of liensinine in nonsmall-cell lung cancer (NSCLC) have not been illustrated. In this study, we demonstrated that liensinine has the potential anti-tumor property, and it could inhibit growth of NSCLC in vitro and in vivo. In addition, we found that although it induced significant accumulation of autophagosomes, liensinine could quench them for degradation and blocked autophagic flux. Importantly, we observed that liensinine inhibited the normal function of mitochondrial energy supply and impaired the lysosomal function. This research firstly provides a possibility insight that liensinine could be a novel therapeutic strategy for NSCLC.

TIPE1, a newly identified member in TIPE (TNFAIP8) family, plays an important role in tumorigenesis and immune regulation, but its role in ovarian cancer, especially in tumor metastasis, remains unknown. In the current study, we aimed to reveal the protein expression spectrum of TIPE1 in normal human tissues and explored its relationship with metastasis in ovarian cancer. The results of IHC staining showed that TIPE1 protein was not only detected in cytoplasm in most human tissues but also expressed in both cytoplasm and nucleus in squamous epithelium and some epithelial-derived cells with secretory functions, such as esophagus, cervix uteri and ovary, and thyroid gland. Moreover, TIPE1 protein was downregulated in ovarian cancer tissues compared with that in the paracancerous. More importantly, TIPE1 suppressed tumorigenesis and metastasis of ovarian cancer in vitro and in vivo, as evidence shows its ability to suppress growth, colony formation, migration, and epithelial-mesenchymal transition (EMT) of ovarian cancer. Taken together, our results demonstrate the suppressor role of TIPE1 in ovarian cancer metastasis, indicating TIPE1 might be a metastasis predictor and a novel therapeutic target for ovarian cancer.

Particulate matter ≤2.5 µm (PM _2.5 ) elevates risks of neurological and chronic metabolic diseases, but the underlying mechanisms linking PM _2.5 ‐induced central nervous system (CNS) injury to metabolic dysfunction remain unclear. Hypothalamic pro‐opiomelanocortin‐expressing (POMC+) neurons regulate systemic metabolic homeostasis, and tripartite motif‐containing protein 31 (TRIM31) modulates inflammation and metabolism. Here, we investigated whether TRIM31 in POMC+ neurons mediates PM _2.5 ‐induced hypothalamic injury and peripheral metabolic disorders in mice subjected to 24‐week PM _2.5 exposure. TRIM31 knockout in POMC ⁺ neurons ( POMC ^Cre/+; TRIM31 ^flox/flox ) exacerbated PM _2.5 ‐;induced increases in mean blood pressure and fat weight, liver weight reduction, adipocyte hypertrophy, hepatic lipid deposition, energy expenditure abnormalities and insulin resistance. It also aggravated hypothalamic damage (downregulated NeuN, POMC and MC4R) and amplified neuroinflammation and oxidative stress. Conversely, AAV‐mediated TRIM31 overexpression in POMC ⁺ neurons alleviated these pathological phenotypes. In vitro, TRIM31 deletion promoted reactive oxygen species (ROS) and inflammation in PM _2.5 ‐challenged hypothalamic neurons and microglia, while TRIM31 overexpression exerted opposite effects; microglial TRIM31 depletion exacerbated neuronal death via conditioned medium. Mechanistically, TRIM31 directly interacted with Nrf2, enhancing its K63‐linked polyubiquitination and reducing K48‐linked polyubiquitination to activate Nrf2 signaling, which was required for TRIM31‐mediated attenuation of neuronal death and inflammation under PM2.5 stress. Collectively, our findings identify the TRIM31/Nrf2 axis as a key molecular switch governing POMC ⁺ neuronal loss, hypothalamic injury and consequent peripheral metabolic disorders triggered by long‐term PM _2.5 exposure.