Rhophilin-2 Upregulates Glutamine Synthetase by Stabilizing c-Myc Protein and Confers Resistance to Glutamine Deprivation in Lung Cancer

Characterizing Genetic Susceptibility to Colorectal Cancer in Taiwan Through Genome-Wide Association Study

We conducted the first genome-wide association study (GWAS) of colorectal cancer (CRC) in Taiwan with 5342 cases and 61,015 controls. Ninety-two SNPs in three genomic regions reached genome-wide significance (p < 5 × 10-8). The lead SNPs in these three regions were: rs12778523 (OR = 1.18, 95% CI, 1.15-1.23, p = 4.51 × 10-13), an intergenic SNP between RNA5SP299 and LINC02676 at chromosome 10p14; rs647161 (OR = 1.14, 95% CI, 1.09-1.19, p = 2.21 × 10-9), an intronic SNP in PITX1 at 5q31.1, and rs10427139 (OR = 1.20, 95% CI, 1.14-1.28, p = 3.62 × 10-9), an intronic SNP in GPATCH1 at 19q13.1. We further validated CRC susceptibility SNPs previously identified through GWAS in other populations. A total of 61 CRC susceptibility SNPs were confirmed in Taiwanese. The top validated putative CRC susceptibility genes included: POU2AF2, HAO1, LAMC1, EIF3H, BMP2, ZMIZ1, BMP4, POLD3, CDKN1A, PREX1, CDKN2B, CDH1, and LRIG1. The top enriched pathways included TGF-β signaling, BMP signaling, extracellular matrix organization, DNA repair, and cell cycle control. We could not validate SNPs in HLA-G at 6p22.1 and in NOTCH4 at 6p21.32. We generated a weighted genetic risk score (GRS) using the 61 SNPs and constructed receiver operating characteristic (ROC) curves using the GRS to predict CRC. The area under the ROC curve (AUC) was 0.589 for GRS alone and 0.645 for GRS, sex, and age. These susceptibility SNPs and genes provide important insights into the molecular mechanisms of CRC development and help identify high-risk individuals for CRC in Taiwan.

Whole-exome sequencing reveals novel genomic signatures and potential therapeutic targets during the progression of rectal neuroendocrine neoplasm

Rectal neuroendocrine neoplasms (rNENs) are among the most frequent gastrointestinal neuroendocrine neoplasms and pose a serious challenge for clinical management. The size of the primary neoplasm is considered to be the most important predictor of disease progression, but the genetic alterations that occur during the progression of rNENs remain unknown. Here, we performed a comprehensive whole-exome sequencing study on 54 tumor-normal paired, formalin-fixed paraffin-embedded specimens from patients locally diagnosed with rNENs. Of these, 81.5% (n = 44) were classified as small-sized (≤2 cm) rNENs, while the remainder (18.5%, n = 10) were classified as large-sized (>2 cm) rNEN samples. Comparative analysis revealed marked disparities in the mutational landscape between small- and large-sized rNEN samples, and between large-sized rNEN samples with or without lymph node metastases. The high-confidence driver genes RHPN2, MUC16, and MUC4 were significantly mutated in both small- and large-sized rNEN specimens, whereas mutations in MAN2A1, and BAG2 were only identified in large-sized specimens diagnosed with lymph node metastases. Correspondingly, we observed that the mTOR and MAPK pathways were preferentially enriched in the large-sized rNEN specimens. Signature-based analysis revealed that mutational processes associated with defective DNA base excision repair (SBS30) significantly accumulated in large-sized rNEN samples with lymph node metastases, highlighting the important role of this mutagenic process in promoting rNEN progression. We further found that most rNEN subjects, regardless of tumor size, harbored at least one alteration with targeted therapeutic implications. Taken together, these results elucidate the genetic features associated with tumor size and lymphatic metastasis in rNEN patients, which will deepen our understanding of the genetic changes during rNEN progression and potentially directing improvements in rNEN treatment strategies.

Targeting cellular adaptive responses to glutaminolysis perturbation for cancer therapy

Metabolic aberrations, notably deviations in glutamine metabolism, are crucial in the oncogenic process, offering vital resources for the unlimited proliferation and enhanced survival capabilities of cancer cells. The dependency of malignant cells on glutamine metabolism has led to the proposition of targeted therapeutic strategies. However, the capability of cancer cells to initiate adaptive responses undermines the efficacy of these therapeutic interventions. This review meticulously examines the multifaceted adaptive mechanisms that cancer cells deploy to sustain survival and growth following the disruption of glutamine metabolism. Emphasis is placed on the roles of transcription factors, alterations in metabolic pathways, the mechanistic target of rapamycin complex 1 signaling axis, autophagy, macropinocytosis, nucleotide biosynthesis, and the scavenging of ROS. Thus, the delineation and subsequent targeting of these adaptive responses in the context of therapies aimed at glutamine metabolism offer a promising avenue for circumventing drug resistance in cancer treatment.

Biomimetic Nanomedicine Targeting Orchestrated Metabolism Coupled with Regulatory Factors to Disrupt the Metabolic Plasticity of Breast Cancer

Targeting nutrient metabolism has been proposed as an effective therapeutic strategy to combat breast cancer because of its high nutrient requirements. However, metabolic plasticity enables breast cancer cells to survive under unfavorable starvation conditions. The key mammalian target regulators rapamycin (mTOR) and hypoxia-inducible-factor-1 (HIF-1) tightly link the dynamic metabolism of glutamine and glucose to maintain nutrient flux. Blocking nutrient flow also induces autophagy to recycle nutrients in the autophagosome, which exacerbates metastasis and tumor progression. Compared to other common cancers, breast cancer is even more dependent on mTOR and HIF-1 to orchestrate the metabolic network. Therefore, we develop a cascade-boosting integrated nanomedicine to reprogram complementary metabolism coupled with regulators in breast cancer. Glucose oxidase efficiently consumes glucose, while the delivery of rapamycin inside limits the metabolic flux of glutamine and uncouples the feedback regulation of mTOR and HIF-1. The hydroxyl radical generated in a cascade blocks the later phase of autophagy without nutrient recycling. This nanomedicine targeting orchestrated metabolism can disrupt the coordination of glucose, amino acids, nucleotides, lipids, and other metabolic pathways in breast cancer tissues, effectively improving the durable antitumor effect and prognosis of breast cancer. Overall, the cascade-boosting integrated system provides a viable strategy to address cellular plasticity and efficient enzyme delivery.

The effects of the prognostic biomarker SAAL1 on cancer growth and its association with the immune microenvironment in lung adenocarcinoma

BACKGROUND

Inhibition of Serum Amyloid A-like 1 (SAAL1) expression could inhibit cancer progression and improve the prognosis of cancer patients. At present, the correlation between SAAL1 and lung adenocarcinoma (LAC) remains unclear. Therefore, this study surveyed the worth and pathway of SAAL1 in LAC progression and immunity.

METHODS

Bioinformatics and immunohistochemistry were used to identify the SAAL1 expression in LAC. The roles of SAAL1 expression in the existence values of LAC patients were explored, and the nomograms were constructed. Clinical values of SAAL1 co-expressed genes were evaluated by COX regression, survival, and Receiver operating characteristic (ROC) analysis. EDU and western blotting methods were used to inquiry the functions and pathways of the SAAL1 in cell growths. The correlation between the SAAL1 level and immune microenvironment was visualized using correlation research.

RESULTS

SAAL1 level was elevated in LAC tissues, and was observed in cancer tissues of dead patients. SAAL1 overexpression had something to do with shorter overall survival, progression-free interval, and disease-specific survival in LAC. The area under the curve of SAAL1 was 0.902 in normal tissues and cancer tissues. Inhibition of SAAL1 expression could inhibit cancer cell proliferation, which may be related to the decreased expression of cyclin D1 and Bcl-2 proteins. In LAC, SAAL1 level had something to do with stromal, immune, and estimate scores, and correlated with macrophages, T cells, Th2 cells, CD8 T cells, NK CD56dim cells, DC, eosinophils, NK CD56bright cells, pDC, iDC, cytotoxic cells, Tgd, aDC cells, B cells, Tcm, and TFH levels. SAAL1 overexpression had something to do with existence values and the immunity in LAC.

CONCLUSIONS

Inhibition of SAAL1 expression could regulate cancer growth via cyclin D1 and Bcl-2. SAAL1 is a promising prognostic biomarker in LAC patients.

Therapeutic Targeting of Glutaminolysis as a Novel Strategy to Combat Cancer Stem Cells

Rare subpopulations of cancer stem cells (CSCs) have the ability to self-renew and are the primary driving force behind cancer metastatic dissemination and the preeminent hurdle to cancer treatment. As opposed to differentiated, non-malignant tumor offspring, CSCs have sophisticated metabolic patterns that, depending on the kind of cancer, rely mostly on the oxidation of major fuel substrates such as glucose, glutamine, and fatty acids for survival. Glutaminolysis is a series of metabolic reactions that convert glutamine to glutamate and, eventually, α-ketoglutarate, an intermediate in the tricarboxylic acid (TCA) cycle that provides biosynthetic building blocks. These building blocks are mostly utilized in the synthesis of macromolecules and antioxidants for redox homeostasis. A recent study revealed the cellular and molecular interconnections between glutamine and cancer stemness in the cell. Researchers have increasingly focused on glutamine catabolism in their attempt to discover an effective therapy for cancer stem cells. Targeting catalytic enzymes in glutaminolysis, such as glutaminase (GLS), is achievable with small molecule inhibitors, some of which are in early-phase clinical trials and have promising safety profiles. This review summarizes the current findings in glutaminolysis of CSCs and focuses on novel cancer therapies that target glutaminolysis in CSCs.

TRAT1 overexpression delays cancer progression and is associated with immune infiltration in lung adenocarcinoma

The roles and mechanisms of T-cell receptor (TCR)-associated transmembrane adaptor 1 (TRAT1) in lung adenocarcinoma (LAC) have not yet been reported in the relevant literature. Therefore, this study aimed to understand the roles and mechanisms of TRAT1 in LAC using bioinformatics and in vitro experiments. TRAT1 expression levels in LAC samples were analysed using various databases. TRAT1 co-expressed genes were acquired by the correlation analysis of LAC tissues. The functional mechanisms and protein network of TRAT1 co-expressed genes were analysed using bioinformatics analysis. The expression of TRAT1 was activated in LAC cells, and the roles of TRAT1 overexpression in the growth and migration of cancer cells was investigated using flow cytometry, Cell Counting Kit-8 (CCK-8), and migration and invasion assays. The relationship between TRAT1 overexpression, the immune microenvironment, and RNA modification was evaluated using correlation analysis. TRAT1 expression levels were significantly abnormal at multiple mutation sites and were related to the prognosis of LAC. TRAT1 co-expressed genes were involved in cell proliferation, adhesion, and differentiation, and TRAT1 overexpression significantly inhibited cell viability, migration, and invasion and promoted apoptosis of A549 and H1299 cells, which might be related to the TCR, B cell receptor (BCR), MAPK, and other pathways. TRAT1 expression levels were significantly correlated with the ESTIMATE, immune, and stromal scores in the LAC microenvironment. Additionally, TRAT1 expression levels were significantly correlated with the populations of B cells, CD8 T cells, cytotoxic cells, and other immune cells. TRAT1 overexpression was significantly correlated with the expression of immune cell markers (such as PDCD1, CD2, CD3E) and genes involved in RNA modification (such as ALKBH1, ALKBH3, ALKBH5). In conclusions, TRAT1 overexpression inhibited the growth and migration of LAC cells, thereby delaying cancer progression, and was correlated with the LAC microenvironment and RNA modifications.

Therapeutic Potential of Glutamine Pathway in Lung Cancer

Cancer cells tend to obtain the substances needed for their development depending on altering metabolic characteristics. Among the reorganized metabolic pathways, Glutamine pathway, reprogrammed to be involved in the physiological process including energy supply, biosynthesis and redox homeostasis, occupies an irreplaceable role in tumor cells and has become a hot topic in recent years. Lung cancer currently maintains a high morbidity and mortality rate among all types of tumors and has been a health challenge that researchers have longed to overcome. Therefore, this study aimed to clarify the essential role of glutamine pathway played in the metabolism of lung cancer and its potential therapeutic value in the interventions of lung cancer.

Construction of an immune-related lncRNA signature as a novel prognosis biomarker for LUAD

The tumor immune microenvironment of lung cancer is associated with prognosis and immunotherapy efficacy. Long noncoding RNAs are identified as prognostic biomarkers associated with immune functions. We constructed a signature comprising differentially expressed immune-related lncRNAs to predict the prognosis of patients with lung adenocarcinoma. We established the immune-related lncRNA signature by pairing immune-related lncRNAs regardless of expression level and lung adenocarcinoma patients were divided into high- and low-risk groups. The prognosis of patients in the two groups was significantly different; The immune-related lncRNA signature could serve as an independent lung adenocarcinoma prognostic indicator. The signature correlated negatively with B cell, CD4+ T cell, M2 macrophage, neutrophil, and monocyte immune infiltration. Patients with low risk scores had a higher abundance of immune cells and stromal cells around the tumor. Gene set enrichment analysis showed that samples from low-risk group were more active in the IgA production in intestinal immune network and the T and B cell receptor signaling pathway. High-risk groups had significant involvement of the cell cycle, DNA replication, adherens junction, actin cytoskeleton regulation, pathways in cancer, and TGF-β signaling pathways. High risk scores correlated significantly negatively with high CTLA-4 and HAVCR2 expression and higher median inhibitory concentration of common anti-tumor chemotherapeutics (e.g., cisplatin, paclitaxel, gemcitabine) and targeted therapy (e.g., erlotinib and gefitinib). We identified a reliable immune-related lncRNA lung adenocarcinoma prognosis model, and the immune-related lncRNA signature showed promising clinical prediction value.