Arenobufagin enhances T-cell anti-tumor immunity in colorectal cancer by modulating HSP90ß accessibility.

BACKGROUND: Colorectal cancer (CRC) is a significant public health issue, ranking as one of the predominant cancer types globally in terms of incidence. Intriguingly, Arenobufagin (Are), a compound extracted from toad venom, has demonstrated the potential to inhibit tumor growth effectively. PURPOSE: This study aimed to explore Are's molecular targets and unravel its antitumor mechanism in CRC. Specifically, we were interested in its impact on immune checkpoint modulation and correlations with HSP90ß-STAT3-PD-L1 axis activity. METHODS: We investigated the in vivo antitumor effects of Are by constructing a colorectalcancer subcutaneous xenograft mouse model. Subsequently, we employed single-cell multi-omics technology to study the potential mechanism by which Are inhibits CRC. Utilizing target-responsive accessibility profiling (TRAP) technology, we identified heatshock protein 90ß (HSP90ß) as the direct target of Are, and confirmed this through a microscale thermophoresis experiment (MST). Further downstream mechanisms were explored through techniques such as co-immunoprecipitation, Western blotting, qPCR, and immunofluorescence. Concurrently, we arrived at the same research conclusion at the organoid level by co-cultivating with immune cells. RESULTS: We observed that Are inhibits PD-Ll expression in CRC tumor xenografts at low concentrations. Moreover, TRAP revealed that HSP90ß's accessibility significantly decreased upon Are binding. We demonstrated a decrease in the activity of the HSP90ß-STAT3-PD-Ll axis following low-concentration Are treatment in vivo. The PDO analysis showed improved enrichment of lymphocytes, particularly T cells, on the PDOs following Are treatment. CONCLUSION: Contrary to previous research focusing on the direct cytotoxicity of Are towards tumor cells, our findings indicate that it can also inhibit tumor growth at lower concentrations through the modulation of immune checkpoints. This study unveils a novel anti-tumor mechanism of Are and stimulates contemplation on the dose-response relationship of natural products, which is beneficial for the clinical translational application of Are.

[Chinese classical formulas Ephedra associated prescriptions for treatment of skin diseases].

Chinese classical formulas, firstly recorded in Shanghan Zabing Lun by Zhang Zhongjing in the Han dynasty, have been widely used by traditional Chinese medicine physicians for thousands of years due to its good compatibility, strict structures, significant clinical efficacy and less adverse effects. Ephedra associated prescriptions, widely used in the treatment of skin diseases, are famous representative prescriptions in Chinese classical formulas. The commonly used Ephedra associated prescriptions include Mahuang Lianqiao Chixiaodou decoction, Maxing Shigan decoction, Maxing Yigan decoction, Mahuang decoction, Mahuang Jiazhu decoction, Guizhi Mahuang Geban decoction, and Guizhi Eryue Biyi decoction. Skin allergy is an allergic reaction, manifested as erythema, papules, and itching. It has been identified that Guizhi Mahuang Geban decoction (1/2 Guizhi decoction + 1/2 Mahuang decoction) is effective in dispersing wind and cold, relieving exterior syndrome and dredging the collaterals, so it can be used to treat skin allergy caused by pathogenic wind-cold. Guizhi Eryue Biyi decoction (1/4 Guizhi decoction + 1/8 Yuebi decoction) is effective in dispersing wind and cold, relieving exterior syndrome and clearing heat, so it is mainly used for the syndrome of wind-cold tightening superficies and heat transformed from wind-cold. Additionally, Mahuang Lianqiao Chixiaodou decoction can relieve exterior syndrome, clear heat and remove dampness, mainly for the dampness and heat depression in the muscle surface. It is found that Guizhi Mahuang Geban decoction and Guizhi Eryue Biyi decoction have certain efficacy for skin allergies, while Mahuang Lianqiao Chixiaodou decoction has significant efficacy for urticaria, acute and chronic eczema, etc. It has been identified that if the conditions of Ephedra associated prescriptions are well mastered by traditional Chinese medicine physicians, they could be widely applied to treat exogenous diseases and miscellaneous diseases.

Genome-wide study of methotrexate clearance replicates SLCO1B1.

Methotrexate clearance can influence the cure of and toxicity in children with acute lymphoblastic leukemia (ALL). We estimated methotrexate plasma clearance for 1279 patients with ALL treated with methotrexate (24-hour infusion of a 1 g/m2 dose or 4-hour infusion of a 2 g/m2 dose) on the Children's Oncology Group P9904 and P9905 protocols. Methotrexate clearance was lower in older children (P = 7 x 10(-7)), girls (P = 2.7 x 10(-4)), and those who received a delayed-intensification phase (P = .0022). A genome-wide analysis showed that methotrexate clearance was associated with polymorphisms in the organic anion transporter gene SLCO1B1 (P = 2.1 x 10(-11)). This replicates findings using different schedules of high-dose methotrexate in St Jude ALL treatment protocols; a combined meta-analysis yields a P value of 5.7 x 10(-19) for the association of methotrexate clearance with SLCO1B1 SNP rs4149056. Validation of this variant with 5 different treatment regimens of methotrexate solidifies the robustness of this pharmacogenomic determinant of methotrexate clearance. This study is registered at http://www.clinicaltrials.gov as NCT00005585 and NCT00005596.