Enhancing anti-tumor immunity by autophagy inhibition

Acidity-Responsive Nanoreactors Destructed "Warburg Effect" for Toxic-Acidosis and Starvation Synergistic Therapy

"Warburg Effect" shows that most tumor cells rely on aerobic glycolysis for energy supply, leading to malignant energy deprivation and an "internal alkaline external acid" tumor microenvironment. Destructing the "Warburg Effect" is an effective approach to inhibit tumor progression. Herein, an acidity-responsive nanoreactor (Au@CaP-Flu@HA) is fabricated for toxic acidosis and starvation synergistic therapy. In the nanoreactor, the fluvastatin (Flu) could reduce lactate efflux by inhibiting the lactate-proton transporter (monocarboxylate transporters, MCT4), resulting in intracellular lactate accumulation. Meanwhile, the glucose oxidase-mimic Au-nanocomposite consumes glucose to induce cell starvation accompanied by gluconic acid production, coupling with lactate to exacerbate toxic acidosis. Also, the up-regulated autophagic energy supply of tumor cells under energy deprivation and hypoxia aggravation is blocked by autophagy inhibitor CaP. Cellular dysfunction under pHi acidification and impaired Adenosine Triphosphate (ATP) synthesis under starvation synergistically promote tumor cell apoptosis. Both in vitro and in vivo studies demonstrate that this combinational approach of toxic-acidosis/starvation therapy could effectively destruct the "Warburg Effect" to inhibit tumor growth and anti-metastatic effects.

Stratification From Heterogeneity of the Cell-Death Signal Enables Prognosis Prediction and Immune Microenvironment Characterization in Esophageal Squamous Cell Carcinoma

Esophageal squamous cell carcinoma (ESCC) is the primary subtype of esophageal cancer (EC) characterized by a high incidence rate and extremely poor prognosis worldwide. Previous studies suggested that the specific cell death signal was linked to different immune subtypes in multiple cancers, while a comprehensive investigation on ESCC is to be performed yet. In the current study, we dissected different cell death signals in ESCC tumors and then integrated that functional information to stratify ESCC patients into different immunogenic cell death (ICD) subtypes. By systematically analyzing the transcriptomes of 857 patients and proteomic profile of 124 patients, we found that the signals of necroptosis, pyroptosis, and ferroptosis are positively associated with activated immunity in ESCC. We identified two ICD pattern terms, namely, ICD-high and ICD-low subtypes that positively correlated to both progression-free survival and overall survival. In addition, cell fraction deconvolution analysis revealed that more infiltrated leukocytes were enriched in ICD-high types, especially antigen-presenting cells, such as dendritic cells and macrophages. With the XGBoost algorithm, we further developed a 14-gene signature which can simplify the subtyping for allocating new samples, by which we validated the prognosis value of the signature and proved that the ICD score scheme could serve as a promising biomarker for stratifying patients with immunotherapy in several immune checkpoint blockade treatment cohorts. Collectively, we successfully constructed the ICD scheme, which enables predicting of the prognosis or immunotherapy efficacy in ESCC patients and uncovered the critical interplay between cell death signals and immune status in ESCC.

Therapeutic Associations Comprising Anti-PD-1/PD-L1 in Breast Cancer: Clinical Challenges and Perspectives

Despite a few cases of long-responder patients, immunotherapy with anti-PD-(L)1 has so far proved rather disappointing in monotherapy in metastatic breast cancer, prompting the use of synergistic therapeutic combinations incorporating immunotherapy by immune-checkpoint inhibitors. In addition, a better understanding of both the mechanisms of sensitivity and resistance to immunotherapy, as well as the immunological effects of the usual treatments for breast cancer, make it possible to rationally consider this type of therapeutic combination. For several years, certain treatments, commonly used to treat patients with breast cancer, have shown that in addition to their direct cytotoxic effects, they may have an impact on the tumor immune microenvironment, by increasing the antigenicity and/or immunogenicity of a "cold" tumor, targeting the immunosuppressive microenvironment or counteracting the immune-exclusion profile. This review focuses on preclinical immunologic synergic mechanisms of various standard therapeutic approaches with anti-PD-(L)1, and discusses the potential clinical use of anti-PD-1/L1 combinations in metastatic or early breast cancer.