Optogenetic manipulation of lysosomal physiology and autophagy-dependent clearance of amyloid beta.

Lysosomes are degradation centers of cells and intracellular hubs of signal transduction, nutrient sensing, and autophagy regulation. Dysfunction of lysosomes contributes to a variety of diseases, such as lysosomal storage diseases (LSDs) and neurodegeneration, but the mechanisms are not well understood. Altering lysosomal activity and examining its impact on the occurrence and development of disease is an important strategy for studying lysosome-related diseases. However, methods to dynamically regulate lysosomal function in living cells or animals are still lacking. Here, we constructed lysosome-localized optogenetic actuators, named lyso-NpHR3.0, lyso-ArchT, and lyso-ChR2, to achieve optogenetic manipulation of lysosomes. These new actuators enable light-dependent control of lysosomal membrane potential, pH, hydrolase activity, degradation, and Ca2+ dynamics in living cells. Notably, lyso-ChR2 activation induces autophagy through the mTOR pathway, promotes Aß clearance in an autophagy-dependent manner in cellular models, and alleviates Aß-induced paralysis in the Caenorhabditis elegans model of Alzheimer's disease. Our lysosomal optogenetic actuators supplement the optogenetic toolbox and provide a method to dynamically regulate lysosomal physiology and function in living cells and animals.

Optogenetic manipulation of lysosomal physiology and autophagic activity.

Lysosomes are essential degradative organelles and signaling hubs within cells, playing a crucial role in the regulation of macroautophagy/autophagy. Dysfunction of lysosomes and impaired autophagy are closely associated with the development of various neurodegenerative diseases. Enhancing lysosomal activity and boosting autophagy levels holds great promise as effective strategies for treating these diseases. However, there remains a lack of methods to dynamically regulate lysosomal activity and autophagy levels in living cells or animals. In our recent work, we applied optogenetics to manipulate lysosomal physiology and function, developing three lysosome-targeted optogenetic tools: lyso-NpHR3.0, lyso-ArchT, and lyso-ChR2. These new actuators enable light-dependent regulation of key aspects such as lysosomal membrane potential, lumenal pH, hydrolase activity, degradation processes, and Ca2+ dynamics in living cells. Notably, lyso-ChR2 activation induces autophagy via the MTOR pathway while it promotes Aß clearance through autophagy induction in cellular models of Alzheimer disease. Furthermore, lyso-ChR2 activation reduces Aß deposition and alleviates Aß-induced paralysis in Caenorhabditis elegans models of Alzheimer disease. Our lysosomal optogenetic actuators offer a novel method for dynamically regulating lysosomal physiology and autophagic activity in living cells and animals.

Inhibition of lysosomal TRPML1 channel eliminates breast cancer stem cells by triggering ferroptosis.

Cancer stem cells (CSCs) are a sub-population of cells possessing high tumorigenic potential, which contribute to therapeutic resistance, metastasis and recurrence. Eradication of CSCs is widely recognized as a crucial factor in improving patient prognosis, yet the effective targeting of these cells remains a major challenge. Here, we show that the lysosomal cation channel TRPML1 represents a promising target for CSCs. TRPML1 is highly expressed in breast cancer cells and exhibits sensitivity to salinomycin, a drug known to selectively eliminate CSCs. Pharmacological inhibition and genetic depletion of TRPML1 promote ferroptosis in breast CSCs, reduce their stemness, and enhance the sensitivity of breast cancer cells to chemotherapy drug doxorubicin. The inhibition and knockout of TRPML1 also demonstrate significant suppression of tumor formation and growth in the mouse xenograft model. These findings suggest that targeting TRPML1 to eliminate CSCs may be an effective strategy for the treatment of breast cancer.

Neoadjuvant chemotherapy combined with immunotherapy versus neoadjuvant chemoradiotherapy in patients with locally advanced esophageal squamous cell carcinoma.

BACKGROUND: To date, few studies have compared effectiveness and survival rates of neoadjuvant chemotherapy combined with immunotherapy (NACI) and conventional neoadjuvant chemoradiotherapy (NCRT) in patients with locally advanced esophageal squamous cell carcinoma (ESCC). The present study was conducted to compare therapeutic response and survival between NACI and NCRT. METHODS: The study cohort comprised patients with locally advanced ESCC treated with either NACI or NCRT followed by surgery between June 2018 and March 2021. The 2 groups were compared for treatment response, 3-year overall survival (OS), and disease-free survival (DFS). Survival curves were created using the Kaplan-Meier method, differences were compared using the log-rank test, and potential imbalances were corrected for using the inverse probability of treatment weighting (IPTW) method. RESULTS: Among 202 patients with locally advanced ESCC, 81 received NACI and 121 received conventional NCRT. After IPTW adjustment, the R0 resection rate (85.2% vs 92.3%; P = .227) and the pathologic complete response (pCR) rate (27.5% vs 36.4%; P = .239) were comparable between the 2 groups. Nevertheless, patients who received NACI exhibited both a better 3-year OS rate (91.7% vs 79.8%; P = .032) and a better 3-year DFS rate (87.4% vs 72.8%; P = .039) compared with NCRT recipients. CONCLUSIONS: NACI has R0 resection and pCR rates comparable to those of NCRT and seems to be correlated with better prognosis than NCRT. NACI followed by surgery may be an effective treatment strategy for locally advanced ESCC.