Despite substantial advances in targeting mutant KRAS, tumor resistance to KRAS inhibitors (KRASi) remains a major barrier to progress. Here, we report proteostasis reprogramming as a key convergence point of multiple KRASi-resistance mechanisms. Inactivation of oncogenic KRAS down-regulated both the heat shock response and the inositol-requiring enzyme 1α (IRE1α) branch of the unfolded protein response, causing severe proteostasis disturbances. However, IRE1α was selectively reactivated in an ER stress–independent manner in acquired KRASi-resistant tumors, restoring proteostasis. Oncogenic KRAS promoted IRE1α protein stability through extracellular signal–regulated kinase (ERK)–dependent phosphorylation of IRE1α, leading to IRE1α disassociation from 3-hydroxy-3-methylglutaryl reductase degradation (HRD1) E3-ligase. In KRASi-resistant tumors, both reactivated ERK and hyperactivated AKT restored IRE1α phosphorylation and stability. Suppression of IRE1α overcame resistance to KRASi. This study reveals a druggable mechanism that leads to proteostasis reprogramming and facilitates KRASi resistance.

The lemon essential oil (LEO), extracted from the fruit of lemon, has been used to treat multiple pathological diseases, such as diabetes, inflammation, cardiovascular diseases, depression and hepatobiliary dysfunction. The study was designed to study the effects of LEO on cognitive dysfunction induced by Alzheimer's disease (AD). We used APP/PS1 double transgene (APP/PS1) AD mice in the experiment; these mice exhibit significant deficits in synaptic density and hippocampal-dependent spatial related memory. The effects of LEO on learning and memory were examined using the Morris Water Maze (MWM) test, Novel object recognition test, and correlative indicators, including a neurotransmitter (acetylcholinesterase, AChE), a nerve growth factor (brain-derived neurotrophic factor, BDNF), a postsynaptic marker (PSD95), and presynaptic markers (synapsin-1, and synaptophysin), in APP/PS1 mice. Histopathology was performed to estimate the effects of LEO on AD mice. A significantly lowered brain AChE depression in APP/PS1 and wild-type C57BL/6L (WT) mice. PSD95/ Synaptophysin, the index of synaptic density, was noticeably improved in histopathologic changes. Hence, it can be summarized that memory-enhancing activity might be associated with a reduction in the AChE levels and is elevated by BDNF, PSD95, and synaptophysin through enhancing synaptic plasticity.

One major reason for the failure of advanced colorectal cancer (CRC) treatment is the occurrence of chemoresistance to fluoropyrimidine (Fu)-based chemotherapy. Accumulating evidence indicates that long non-coding RNAs (lncRNAs) play a critical role in cancerous processes as either oncogenes or tumor suppressor genes. Here, we observed lncRNA TUG1 was associated to the 5-Fu resistance in colorectal cancer. Firstly, quantitative analysis indicated that TUG1 was significantly increased in recurrence CRC patient samples. Kaplan-Meier survival analysis indicated that high TUG1 expression in CRC tissues was significantly associated with a higher rate of disease progression. TUG1 knockdown re-sensitized the 5-Fu resistance in colorectal cancer cells, which were 5-Fu-resistant colorectal cell line. Furthermore, bioinformatics analysis showed that miR-197-3p could directly bind to TUG1 suggesting TUG1 might work as a ceRNA to sponge miR-197-3p. Extensively, our study also showed that TYMS was the direct target of miR-197-3p in CRC cells. Taken together, our study suggests that TUG1 mediates 5-Fu resistance in CRC via miR-197-3p/TYMS axis.

For its various important functions in cells, phosphatase and tensin homolog‐induced kinase 1 (PINK1) has drawn considerable attention for the role it plays in early‐onset Parkinson's disease. In recent years, emerging evidence has supported the hypothesis that PINK1 plays a part in regulating many physiological and pathophysiological processes in cancer cells, including cytoplasmic homeostasis, cell survival, and cell death. According to the findings of these studies, PINK1 can function as a tumor promoter or suppressor, showing a duality that is dependent on the context. In this study we review the mechanistic characters relating to PINK1 based on available published data from peer‐reviewed articles, The Cancer Genome Atlas data mining, and cell‐based assays. This mini review focuses on some of the interplays between PINK1 and the context and recent developments in the field, including its growing involvement in mitophagy and its nonmitophagy organelles‐related function. This review aims to help readers better grasp how PINK1 is functioning in cell physiological and pathophysiological processes, especially in cancer biology.