PEG-BCT-100 and Canavanine Synergistically Induce Apoptosis in Arginine Biosynthetic Enzyme-Deficient Pancreatic Cancer.

This study investigates the synergistic antitumor effect of PEG-BCT-100, an arginase, in clinical trials, with canavanine in pancreatic cancer, in vitro and in vivo. The treatment induces cancer cell apoptosis while sparing normal fibroblasts. Our findings suggest heightened susceptibility of pancreatic tumors deficient in arginine biosynthesis enzymes ASS1 and OTC.

Pharmacological activation of STAT1-GSDME pyroptotic circuitry reinforces epigenetic immunotherapy for hepatocellular carcinoma.

Background: Genomic screening uncovered interferon-gamma (IFNγ) pathway defects in tumours refractory to immune checkpoint blockade (ICB). However, its non-mutational regulation and reversibility for therapeutic development remain less understood.

Objective: We aimed to identify ICB resistance-associated druggable histone deacetylases (HDACs) and develop a readily translatable combination approach for patients with hepatocellular carcinoma (HCC).

PPP1R15A-expressing monocytic MDSCs promote immunosuppressive liver microenvironment in fibrosis-associated hepatocellular carcinoma.

Background & Aims: Recent studies demonstrated the importance of fibrosis in promoting an immunosuppressive liver microenvironment and thereby aggressive hepatocellular carcinoma (HCC) growth and resistance to immune checkpoint blockade (ICB), particularly via monocyte-to-monocytic myeloid-derived suppressor cell (M-MDSC) differentiation triggered by hepatic stellate cells (HSCs). We thus aimed to identify druggable targets in these immunosuppressive myeloid cells for HCC therapy.

Methods: M-MDSC signature genes were identified by integrated transcriptomic analysis of a human HSC-monocyte culture system and tumor-surrounding fibrotic livers of patients with HCC.

Chemotherapy-induced recruitment of myeloid-derived suppressor cells abrogates efficacy of immune checkpoint blockade.

Background & Aims: Immune checkpoint blockade (ICB) has been approved for treatment of hepatocellular carcinoma (HCC). However, many patients with advanced HCC are non-responders to ICB monotherapy. Cytotoxic chemotherapy has been proposed to modulate the tumor microenvironment (TME) and sensitize tumors to ICB.

Phthalaldehyde-Amine Capture Reactions for Bioconjugation and Immobilization of Phthalocyanines.

A phthalaldehyde-substituted phthalocyanine has been synthesized that can conjugate with a range of biomolecules, including peptides, monosaccharides, lipids, and DNAs, and be immobilized on the surface of bovine serum album nanoparticles and glass slides using the versatile and efficient phthalaldehyde-amine capture reactions. The light-induced cytotoxic effects of the latter two materials have also been examined against cancer cells and bacteria, respectively, showing that they are highly efficient photosensitizing systems for photodynamic therapy.