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Abstract Aggressive nature of colon cancer and current imprecise therapeutic scenarios simulate the development of precise and effective treatment strategies. To achieve this, a tumor environment‐activated photosensitized biomimetic nanoplatform (PEG2000‐SiNcTI‐Ph/CpG‐ZIF‐8@CM) is fabricated by encapsulating metal‐organic framework loaded with developed photosensitizer PEG2000‐SiNcTI‐Ph and immunoadjuvant CpG oligodeoxynucleotide within fusion cell membrane expressing programmed death protein 1 (PD‐1) and cluster of differentiation 47 (CD47). By stumbling across, systematic evaluation, and deciphering with quantum chemical calculations, a unique attribute of tumor environment (low pH plus high concentrations of adenosine 5′‐triphosphate (ATP))‐activated photodynamic effect sensitized by long‐wavelength photons is validated for PEG2000‐SiNcTI‐Ph/CpG‐ZIF‐8@CM, advancing the precision of cancer therapy. Moreover, PEG2000‐SiNcTI‐Ph/CpG‐ZIF‐8@CM evades immune surveillance to target CT26 colon tumors in mice mediated by CD47/signal regulatory proteins α (SIRPα) interaction and PD‐1/programmed death ligand 1 (PD‐L1) interaction, respectively. Tumor environment‐activated photodynamic therapy realized by PEG2000‐SiNcTI‐Ph/CpG‐ZIF‐8@CM induces immunogenic cell death (ICD) to elicit anti‐tumor immune response, which is empowered by enhanced dendritic cells (DC) uptake of CpG and PD‐L1 blockade contributed by the nanoplatform. The photodynamic immunotherapy efficiently combats primary and distant CT26 tumors, and additionally generates immune memory to inhibit tumor recurrence and metastasis. The nanoplatform developed here provides insights for the development of precise cancer therapeutic strategies.

Abstract Targeting cancer‐specific metabolic processes is a promising therapeutic strategy. Here, this work uses a compound library that directly inhibits metabolic enzymes to screen the potential metabolic targets in lung adenocarcinoma (LUAD). SHIN1, the specific inhibitor of serine hydroxymethyltransferase 1/2 (SHMT1/2), has a highly specific inhibitory effect on LUAD cells, and this effect depends mainly on the overexpression of SHMT2. This work clarifies that mitogen‐activated protein kinase 1 (MAPK1)‐mediated phosphorylation at Ser90 is the key mechanism underlying SHMT2 upregulation in LUAD and that this phosphorylation stabilizes SHMT2 by reducing STIP1 homology and U‐box containing protein 1 (STUB1)‐mediated ubiquitination and degradation. SHMT2‐Ser90 dephosphorylation decreases S‐adenosylmethionine levels in LUAD cells, resulting in reduced N6‐methyladenosine (m6A) levels in global RNAs without affecting total protein or DNA methylation. Methylated RNA immunoprecipitation sequencing (MeRIP‐Seq) and RNA sequencing (RNA‐Seq) analyses further demonstrate that SHMT2‐Ser90 dephosphorylation accelerates the RNA degradation of oncogenic genes by reducing m6A modification, leading to the inhibition of tumorigenesis. Overall, this study elucidates a new regulatory mechanism of SHMT2 during oncogenesis and provides a theoretical basis for targeting SHMT2 as a therapeutic target in LUAD.

Abstract Mitochondrial dysfunction and abnormal energy metabolism are major features of cancer. However, the mechanisms underlying mitochondrial dysfunction during cancer progression are far from being clarified. Here, it is demonstrated that the expression level of succinyl‐coenzyme A (CoA) synthetase GDP‐forming subunit β (SUCLG2) can affect the overall succinylation of lung adenocarcinoma (LUAD) cells. Succinylome analysis shows that the deletion of SUCLG2 can upregulate the succinylation level of mitochondrial proteins and inhibits the function of key metabolic enzymes by reducing either enzymatic activity or protein stability, thus dampening mitochondrial function in LUAD cells. Interestingly, SUCLG2 itself is also succinylated on Lys93, and this succinylation enhances its protein stability, leading to the upregulation of SUCLG2 and promoting the proliferation and tumorigenesis of LUAD cells. Sirtuin 5 (SIRT5) desuccinylates SUCLG2 on Lys93, followed by tripartite motif‐containing protein 21 (TRIM21)‐mediated ubiquitination through K63‐linkage and degradation in the lysosome. The findings reveal a new role for SUCLG2 in mitochondrial dysfunction and clarify the mechanism of the succinylation‐mediated protein homeostasis of SUCLG2 in LUAD, thus providing a theoretical basis for developing anti‐cancer drugs targeting SUCLG2.