Apolipoprotein C-II induces EMT to promote gastric cancer peritoneal metastasis via PI3K/AKT/mTOR pathway

Ovarian cancer ascites proteomic profile reflects metabolic changes during disease progression

Ovarian cancer (OC) patients develop ascites, an accumulation of ascitic fluid in the peritoneal cavity anda sign of tumour dissemination within the peritoneal cavity. This body fluid is under-researched, mainly regarding the ascites formed during tumour progression that have no diagnostic value and, therefore, are discarded. We performed a discovery proteomics study to identify new biomarkers in the ascites supernatant of OC patients. In this preliminary study, we analyzed a small amount of OC ascites to highlight the importance of not discarding such biological material during treatment, which could be valuable for OC management. Our findings reveal that OC malignant ascitic fluid (MAF) displays a proliferative environment that promotes the growth of OC cells that shift the metabolic pathway using alternative sources of nutrients, such as the cholesterol pathway. Also, OC ascites drained from patients during treatment showed an immunosuppressive environment, with up-regulation of proteins from the signaling pathways of IL-4 and IL-13 and down-regulation from the MHC-II. This preliminary study pinpointed a new protein (Transmembrane Protein 132A) in the OC context that deserves to be better explored in a more extensive cohort of patients' samples. The proteomic profile of MAF from OC patients provides a unique insight into the metabolic kinetics of cancer cells during disease progression, and this information can be used to develop more effective treatment strategies.

Pharmacological Inhibition or Silencing of TREM1 Restrains HCC Cell Metastasis by Inactivating TLR/PI3K/AKT Signaling

Hepatocellular carcinoma (HCC), a widely prevalent malignancy strongly linked to inflammation, remains a significant public health concern. Triggering receptor expressed on myeloid cells 1 (TREM1), a modulator of inflammatory responses identified in recent years, has emerged as a crucial facilitator in cancer progression. Despite its significance, the precise regulatory mechanism of TREM1 in HCC metastasis remains unanswered. In the present investigation, we observed aberrant upregulation of TREM1 in HCC tissues, which was significantly linked to poorer overall survival. Inhibition of TREM1 expression resulted in a significant reduction in HCC Huh-7 and MHCC-97H cell proliferation, invasion, and epithelial-mesenchymal transition (EMT) process. Furthermore, inhibiting TREM1 decreased protein expressions of toll-like receptor 2/4 (TLR2/4) and major myeloid differentiation response gene 88 (MyD88), leading to the inactivation of phosphatidylinositol 3-kinase (PI3K) and protein kinase B (AKT) in HCC cells. Notably, these effects were reversed by treatment with TLR2-specific agonist (CU-T12-9), indicating a potential crosstalk between TREM1 and TLR2/4. Mechanistic studies revealed a direct interaction between TREM1 and both TLR2 and TLR4. In vivo studies demonstrated that inhibition of TREM1 suppressed the growth of HCC cells in the orthotopic implant model and its metastatic potential in the experimental lung metastasis model. Overall, our findings underscore the role of TREM1 inhibition in regulating EMT and metastasis of HCC cells by inactivating the TLR/PI3K/AKT signaling pathway, thereby providing deeper mechanistic insights into how TREM1 regulates metastasis during HCC progression.

AURKB targets DHX9 to promote hepatocellular carcinoma progression via PI3K/AKT/mTOR pathway

Aurora kinase B (AURKB) is known to play a carcinogenic role in a variety of cancers, but its underlying mechanism in liver cancer is unknown. This study aimed to investigate the role of AURKB in hepatocellular carcinoma (HCC) and its underlying molecular mechanism. Bioinformatics analysis revealed that AURKB was significantly overexpressed in HCC tissues and cell lines, and its high expression was associated with a poorer prognosis in HCC patients. Furthermore, downregulation of AURKB inhibited HCC cell proliferation, migration, and invasion, induced apoptosis, and caused cell cycle arrest. Moreover, AURKB downregulation also inhibited lung metastasis of HCC. AURKB interacted with DExH-Box helicase 9 (DHX9) and targeted its expression in HCC cells. Rescue experiments further demonstrated that AURKB targeting DHX9 promoted HCC progression through the PI3K/AKT/mTOR pathway. Our results suggest that AURKB is significantly highly expressed in HCC and correlates with patient prognosis. Targeting DHX9 with AURKB promotes HCC progression via the PI3K/AKT/mTOR pathway.

iJAZ-based approach to engineer lepidopteran pest resistance in multiple crop species

The fall armyworm (FAW) poses a significant threat to global crop production. Here we showed that overexpression of jasmonate ZIM-domain (JAZ) protein GhJAZ24 confers resistance to cotton bollworm and FAW, while also causing sterility in transgenic cotton by recruiting TOPLESS and histone deacetylase 6. We identified the NGR motif of GhJAZ24 that recognizes and binds the aminopeptidase N receptor, enabling GhJAZ24 to enter cells and disrupt histone deacetylase 3, leading to cell death. To overcome plant sterility associated with GhJAZ24 overexpression, we developed iJAZ (i, induced), an approach involving damage-induced expression and a switch from intracellular to extracellular localization of GhJAZ24. iJAZ transgenic cotton maintained fertility and showed insecticidal activity against cotton bollworm and FAW. In addition, iJAZ transgenic rice, maize and tobacco plants showed insecticidal activity against their lepidopteran pests, resulting in an iJAZ-based approach for generating alternative insecticidal proteins with distinctive mechanisms of action, thus holding immense potential for future crop engineering.

CCL2 promotes metastasis and epithelial-mesenchymal transition of non-small cell lung cancer via PI3K/Akt/mTOR and autophagy pathways

In non-small cell lung cancer (NSCLC), metastasis is the most common phenotype, and autophagy plays a vital role in its regulation. However, there are limited data on how autophagy-related genes and metastasis-related genes affect NSCLC progression. Our goal was to identify the genes that regulate autophagy and metastasis in NSCLC, and to assess the underlying mechanisms in this current study. RNA sequencing data from public databases were used to screen differentially expressed autophagy- and metastasis-associated genes. Enrichment analyses and immune correlations were conducted to identify hub genes and potential regulating pathways in NSCLC. In this study, we found that CCL2 expression was highly expressed in NSCLC tissues and high CCL2 level was correlated with strong infiltration in lung tissues from NSCLC patients. Overexpression of CCL2 can enhance the metastasis of NSCLC cells in nude mice. Furthermore, CCL2 activated the PI3K/Akt/mTOR signalling pathway axis, promoted epithelial-mesenchymal transition (EMT), and blocked the autophagic flux in NSCLC cells. Therefore, our results indicate that CCL2 promotes metastasis and EMT of NSCLC via PI3K/Akt/mTOR axis and autophagy signalling pathways. We believe that CCL2 could be a probable target for the diagnosis and therapeutics of NSCLC, and this study may expand our understanding of lung cancer.

N6-methyladenosine-modified MIB1 promotes stemness properties and peritoneal metastasis of gastric cancer cells by ubiquitinating DDX3X

BACKGROUND

Peritoneal metastasis (PM), one of the most typical forms of metastasis in advanced gastric cancer (GC), indicates a poor prognosis. Exploring the potential molecular mechanism of PM is urgently necessary, as it has not been well studied. E3 ubiquitin ligase has been widely established to exert a biological function in various cancers, but its mechanism of action in GC with PM remains unknown.

METHODS

The effect of MIB1 on PM of GC was confirmed in vitro and in vivo. Co-immunoprecipitation (Co-IP) and mass spectrometry demonstrated the association between MIB1 and DDX3X. Western blot, flow cytometry and immunofluorescence determined that DDX3X was ubiquitylated by MIB1 and promoted stemness. We further confirmed that METTL3 promoted the up-regulation of MIB1 by RNA immunoprecipitation (RIP), luciferase reporter assay and other experiments.

RESULTS

We observed that the E3 ubiquitin ligase Mind bomb 1 (MIB1) was highly expressed in PMs, and patients with PM with high MIB1 expression showed a worse prognosis than those with low MIB1 expression. Mechanistically, our study demonstrated that the E3 ubiquitin ligase MIB1 promoted epithelial-mesenchymal transition (EMT) progression and stemness in GC cells by degrading DDX3X. In addition, METTL3 mediated m6A modification to stabilize MIB1, which required the m6A reader IGF2BP2.

CONCLUSIONS

Our study elucidated the specific molecular mechanism by which MIB1 promotes PM of GC, and suggested that targeting the METTL3-MIB1-DDX3X axis may be a promising therapeutic strategy for GC with PM.

Nanomechanical Analysis of Living Small Extracellular Vesicles to Identify Gastric Cancer Cell Malignancy Based on a Biomimetic Peritoneum

Gastric cancer is one of the most prevalent digestive malignancies. The lack of effective in vitro peritoneal models has hindered the exploration of the potential mechanisms behind gastric cancer's peritoneal metastasis. An accumulating body of research indicates that small extracellular vesicles (sEVs) play an indispensable role in peritoneal metastasis of gastric cancer cells. In this study, a biomimetic peritoneum was constructed. The biomimetic model is similar to real peritoneum in internal microstructure, composition, and primary function, and it enables the recurrence of peritoneal metastasis process in vitro. Based on this model, the association between the mechanical properties of sEVs and the invasiveness of gastric cancer was identified. By performing nanomechanical analysis on sEVs, we found that the Young's modulus of sEVs can be utilized to differentiate between malignant clinical samples (ascites) and nonmalignant clinical samples (peritoneal lavage). Furthermore, patients' ascites-derived sEVs were verified to stimulate the mesothelial-to-mesenchymal transition, thereby promoting peritoneal metastasis. In summary, nanomechanical analysis of living sEVs could be utilized for the noninvasive diagnosis of malignant degree and peritoneal metastasis of gastric cancer. This finding is expected to contribute future treatments.

Lipid Metabolism-Related Gene Signature Predicts Prognosis and Indicates Immune Microenvironment Infiltration in Advanced Gastric Cancer

Objective

Abnormal lipid metabolism is known to influence the malignant behavior of gastric cancer. However, the underlying mechanism remains elusive. In this study, we comprehensively analyzed the biological significance of genes involved in lipid metabolism in advanced gastric cancer (AGC).

Methods

We obtained gene expression profiles from The Cancer Genome Atlas (TCGA) database for early and advanced gastric cancer samples and performed differential expression analysis to identify specific lipid metabolism-related genes in AGC. We then used consensus cluster analysis to classify AGC patients into molecular subtypes based on lipid metabolism and constructed a diagnostic model using least absolute shrinkage and selection operator- (LASSO-) Cox regression analysis and Gene Set Enrichment Analysis (GSEA). We evaluated the discriminative ability and clinical significance of the model using the Kaplan-Meier (KM) curve, ROC curve, DCA curve, and nomogram. We also estimated immune levels based on immune microenvironment expression, immune checkpoints, and immune cell infiltration and obtained hub genes by weighted gene co-expression network analysis (WGCNA) of differential genes from the two molecular subtypes.

Results

We identified 6 lipid metabolism genes that were associated with the prognosis of AGC and used consistent clustering to classify AGC patients into two subgroups with significantly different overall survival and immune microenvironment. Our risk model successfully classified patients in the training and validation sets into high-risk and low-risk groups. The high-risk score predicted poor prognosis and indicated low degree of immune infiltration. Subgroup analysis showed that the risk model was an independent predictor of prognosis in AGC. Furthermore, our results indicated that most chemotherapeutic agents are more effective for AGC patients in the low-risk group than in the high-risk group, and risk scores for AGC are strongly correlated with drug sensitivity. Finally, we performed qRT-PCR experiments to verify the relevant results.

Conclusion

Our findings suggest that lipid metabolism-related genes play an important role in predicting the prognosis of AGC and regulating immune invasion. These results have important implications for the development of targeted therapies for AGC patients.

Targeting PI3K/AKT/mTOR and MAPK Signaling Pathways in Gastric Cancer

Gastric cancer (GC) is the fourth leading cause of death worldwide, with more than 1 million cases diagnosed every year. Helicobacter pylori represents the main risk factor, being responsible for 78% of the cases. Increased amounts of salt, pickled food, red meat, alcohol, smoked food, and refined sugars negatively affect the stomach wall, contributing to GC development. Several gene mutations, including PIK3CA, TP53, ARID1A, CDH1, Ras, Raf, and ERBB3 are encountered in GC pathogenesis, leading to phosphatidylinositol 3-kinase (PI3K) protein kinase B (AKT)/mammalian target of rapamycin (mTOR)-PI3K/AKT/mTOR-and mitogen-activated protein kinase (MAPK) signaling pathway activation and promoting tumoral activity. Helicobacter pylori, growth factors, cytokines, hormones, and oxidative stress also activate both pathways, enhancing GC development. In clinical trials, promising results have come from monoclonal antibodies such as trastuzumab and ramucirumab. Dual inhibitors targeting the PI3K/AKT/mTOR and MAPK signaling pathways were used in vitro studies, also with promising results. The main aim of this review is to present GC incidence and risk factors and the dysregulations of the two protein kinase complexes together with their specific inhibitors.

miR-1182-mediated ALDH3A2 inhibition affects lipid metabolism and progression in ccRCC by activating the PI3K-AKT pathway

In clear cell renal cell carcinoma (ccRCC), dysregulated lipid metabolism plays a pivotal role in tumor initiation and progression. This study delves into the unexplored landscape of Dysregulated Aldehyde Dehydrogenase 3 Family Member A2 (ALDH3A2) in ccRCC. Using a combination of "fatty acid metabolism" dataset analysis and differentially expressed genes (DEGs) derived from Gene Expression Omnibus (GEO) database, potential metabolic regulators in ccRCC were identified. Subsequent investigations utilizing public databases, clinical samples, and in vitro experiments revealed that ALDH3A2 was down-regulated in ccRCC, mediated by miR-1182, highlighting its role as an independent prognostic factor for patient survival. Functionally, ALDH3A2 exhibited tumor-suppressive properties, impacting ccRCC cell phenotypes and influencing epithelial-mesenchymal transition. Mechanistically, silencing ALDH3A2 promoted lipid accumulation in ccRCC cells by activating the PI3K-AKT pathway, thereby promoting tumor progression. These findings shed light on the critical role of the miR-1182/ALDH3A2 axis in ccRCC tumorigenesis, emphasizing the potential for targeting lipid metabolism as a promising anti-cancer strategy.

FKBP38 suppresses endometrial cancer cell proliferation and metastasis by inhibiting the mTOR pathway

Endometrial cancer (EC) is a common gynecological malignancy, and advanced-stage or recurrent EC is associated with a high mortality rate owing to the ineffectiveness of currently available treatments. FK506-binding protein 38 (FKBP38) is a member of the immunophilin family and inhibits melanoma and breast cancer cell metastasis. However, the functions of FKBP38 and its potential mechanism in EC remain unclear. Herein, we analyzed the expression levels of FKBP38 in EC cells and found that the FKBP38 expression was high in Ishikawa cells, and low in AN3CA cells, traditionally considered a low grade and a high grade cell line, respectively, in pathology classification. Moreover, FKBP38 inhibited cell proliferation, migration and invasion in EC cells, FKBP38 knockdown significantly promoted tumor growth of Ishikawa cells in a subcutaneous xenograft model and increased the number of lung metastases of Hec-1-A cells in a metastatic mouse model. Furthermore, FKBP38 suppressed several target proteins of epithelial-to-mesenchymal transition (EMT) and reduced the phosphorylation of ribosomal S6 protein (S6), eukaryotic initiation factor 4E-binding protein 1 (4EBP-1), indicating the potent inhibition of the mammalian target of rapamycin (mTOR) pathway. Meanwhile, the inhibition of mTOR neutralized the elevation of EC cell proliferation, migration and invasion after FKBP38 knockdown. In summary, FKBP38 would exert a tumor-suppressing role by modulating the mTOR pathway. Our results indicate that FKBP38 may be considered as a factor of EC metastasis and a new target for EC therapeutic intervention.

Inside anticancer therapy resistance and metastasis. Focus on CD36

Despite recent advances in targeted cancer therapies, drug resistance remains an important setback in tumor control. Understanding the complex mechanisms involved in both innate and acquired drug resistance represents the first step in discovering novel therapeutic agents. Because of its importance in tumorigenesis, progression, and metastasis, lipid metabolism is increasingly garnering attention. CD36 is a membrane receptor at the top of the signaling cascade that transports lipids. Its expression has been repeatedly presented as an unfavorable prognostic factor for various tumor types, raising the question: could CD36 be a critical factor in cancer treatment resistance? In our review, we set out to explore the most prominent studies on the implication of CD36 in resistance to platinum-based drugs and other adjuvant cancer therapies in solid and haematological neoplasia. Moreover, we provide an overview of the latest anti-CD36 cancer therapies, thus opening new perspectives for future personalized medicine.

AKR1B10 inhibits the proliferation and metastasis of hepatocellular carcinoma cells by regulating the PI3K/AKT pathway

Hepatocellular carcinoma (HCC) is one of the most frequent and aggressive malignant neoplasms, and is associated with a poor prognosis. Therefore, there is a crucial need to develop novel cancer therapies and identify novel therapeutic targets. Aldo-keto reductase family 1 member B10 (AKR1B10) is expressed in various types of cancer. However, the role of AKR1B10 in the pathological process of HCC and its underlying molecular mechanism is poorly understood. AKR1B10 expression was evaluated pan-cancer and in HCC using the Genomic Data Commons-The Cancer Genome Atlas (GDC-TCGA) and International Cancer Genome Consortium (ICGC) databases. The relationship between elevated AKR1B10 expression and overall survival in HCC patients was analyzed using a Kaplan-Meier plot. The effects of AKR1B10 on the proliferation, migration, and invasion of HCC cells were evaluated. The proliferation of HCC was measured using CCK-8 and colony formation assays. Transwell and wound healing assays were used to assess the migration and invasion of HCC cells. Western blots were used to detect the expression of proliferative and epithelial-mesenchymal transition (EMT) related proteins in HCC cells, including CCND1, E-cadherin, N-cadherin, vimentin, Twist1, PI3K/p-PI3K, and AKT/p-AKT. AKR1B10 expression was significantly upregulated pan-cancer and in liver cancer. Upregulated AKR1B10 expression was associated with a worse overall survival. HCC cell proliferation, migration, and invasion were found to be influenced by AKR1B10 activity, as demonstrated using DepMap analysis. AKR1B10 knockdown in Huh7 cells reduced proliferation, migration, invasion, and EMT. Mechanistically, AKR1B10 increased the expression of proliferative and EMT-related proteins CCND1, E-cadherin, N-cadherin, vimentin, and Twist1. PI3K and AKT phosphorylation levels decreased following AKR1B10 knockdown. In conclusion, AKR1B10 promoted the proliferation, migration, and invasion of HCC cells via the PI3K/AKT signaling pathway, a potential prognostic indicator.

Effect of metabolic reprogramming on the immune microenvironment in gastric cancer

Gastric cancer (GC) is a malignant tumor of the gastrointestinal tract with a high mortality rate worldwide, a low early detection rate and a poor prognosis. The rise of metabolomics has facilitated the early detection and treatment of GC. Metabolism in the GC tumor microenvironment (TME) mainly includes glucose metabolism, lipid metabolism and amino acid metabolism, which provide energy and nutrients for GC cell proliferation and migration. Abnormal tumor metabolism can influence tumor progression by regulating the functions of immune cells and immune molecules in the TME, thereby contributing to tumor immune escape. Thus, in this review, we summarize the impact of metabolism on the TME during GC progression. We also propose novel strategies to modulate antitumor immune responses by targeting metabolism.

Ligand-dependent CD36 functions in cancer progression, metastasis, immune response, and drug resistance

CD36, a multifunctional glycoprotein, has been shown to play critical roles in tumor initiation, progression, metastasis, immune response, and drug resistance. CD36 serves as a receptor for a wide range of ligands, including lipid-related ligands (e.g., long-chain fatty acid (LCFA), oxidized low-density lipoprotein (oxLDL), and oxidized phospholipids), as well as protein-related ligands (e.g., thrombospondins, amyloid proteins, collagens I and IV). CD36 is overexpressed in various cancers and may act as an independent prognostic marker. While it was initially identified as a mediator of anti-angiogenesis through its interaction with thrombospondin-1 (TSP1), recent research has highlighted its role in promoting tumor growth, metastasis, drug resistance, and immune suppression. The varied impact of CD36 on cancer is likely ligand-dependent. Therefore, we focus specifically on the ligand-dependent role of CD36 in cancer to provide a critical review of recent advances, perspectives, and challenges.

Targeting HSP90 with picropodophyllin suppresses gastric cancer tumorigenesis by disrupting the association of HSP90 and AKT

Gastric cancer (GC) is one of the most common malignant tumors worldwide. Thus, the development of safe and effective therapeutic compounds for GC treatment is urgently required. Here, we aimed to examine the role of picropodophyllin (PPP), a compound extracted from the rhizome of Dysosma versipellis (Hance) M. Cheng ex Ying, on the proliferation of GC cells. Our study revealed that PPP inhibits the proliferation of GC cells in a dose-dependent manner by inducing apoptosis. Moreover, our study elucidated that PPP suppresses the growth of GC tumor xenografts with no side effects of observable toxicity. Mechanistically, PPP exerts its effects by blocking the AKT/mammalian target of rapamycin (mTOR) signaling pathway; these effects are markedly abrogated by the overexpression of constitutively active AKT. Furthermore, drug affinity responsive target stability (DARTS) and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) revealed that heat shock protein 90 (HSP90) may be a potential target of PPP. Surface plasmon resonance and immunoprecipitation assay validated that PPP directly targets HSP90 and disrupts the binding of HSP90 to AKT, thereby suppressing GC cell proliferation. Thus, our study revealed that PPP may be a promising therapeutic compound for GC treatment.

ACLY promotes gastric tumorigenesis and accelerates peritoneal metastasis of gastric cancer regulated by HIF-1A

Mounting evidence indicates the potential involvement of ATP-citrate lyase (ACLY) in the modulation of various cancer types. Nevertheless, the precise biological significance of ACLY in gastric cancer (GC) remains elusive. This study sought to elucidate the biological function of ACLY and uncover its influence on peritoneal metastasis in GC. The expression of ACLY was assessed using both real-time quantitative PCR and western blot techniques. To investigate the impact of ACLY on the proliferation of gastric cancer (GC) cells, colony formation and 5-ethynyl-2'-deoxyuridine (EdU) assays were performed. The migratory and invasive abilities of GC were evaluated using wound healing and transwell assays. Additionally, a bioinformatics analysis was employed to predict the correlation between ACLY and HIF-1A. This interaction was subsequently confirmed through a chromatin immunoprecipitation (ChIP) assay. ACLY exhibited upregulation in gastric cancer (GC) as well as in peritoneal metastasis. Its overexpression was found to facilitate the proliferation and metastasis of GC cells in both in vitro and in vivo experiments. Moreover, ACLY was observed to play a role in promoting angiogenesis and epithelial-mesenchymal transition (EMT). Notably, under hypoxic conditions, HIF-1A levels were elevated, thereby acting as a transcription factor to upregulate ACLY expression. Under the regulatory influence of HIF-1A, ACLY exerts a significant impact on the progression of gastric cancer, thereby facilitating peritoneal metastasis.

METTL3 promotes drug resistance to oxaliplatin in gastric cancer cells through DNA repair pathway

Gastric cancer (GC) poses a significant threat to human health and remains a prevalent form of cancer. Despite clinical treatments, the prognosis for Gastric cancer patients is still unsatisfactory, largely due to the development of multidrug resistance. Oxaliplatin (OXA), a second-generation platinum drug, is commonly recommended for adjuvant and palliative chemotherapy in Gastric cancer; however, the underlying mechanisms of acquired resistance to Oxaliplatin in Gastric cancer patients are not yet fully understood. In this study, we aimed to explore the potential mechanisms of Oxaliplatin resistance in Gastric cancer by employing bioinformatics analysis and conducting in vitro experiments. Specifically, we focused on investigating the role of methyltransferase-like 3 (METTL3). Our findings revealed that the knockdown of METTL3 significantly impeded the proliferation and migration of Gastric cancer cells. METTL3 knockdown induced apoptosis in OXA-resistant Gastric cancer cells and enhanced their sensitivity to Oxaliplatin. Furthermore, we found that DNA repair pathways were significantly activated in OXA-resistant Gastric cancer cells, and METTL3 knockdown significantly inhibited DNA repair pathways. Another important finding is that METTL3 knockdown and OXA-induced Gastric cancer cell death are additive, and the targeted METTL3 can assist Oxaliplatin treatment. Collectively, our findings suggest that METTL3 knockdown can augment the sensitivity of Gastric cancer cells to Oxaliplatin by impeding DNA repair processes. Consequently, targeting METTL3 holds great promise as a viable adjuvant strategy in the treatment of Gastric cancer patients.

Single-cell transcriptomic analysis uncovers the origin and intratumoral heterogeneity of parotid pleomorphic adenoma

Pleomorphic adenoma (PA) is the most common benign tumour in the salivary gland and has high morphological complexity. However, the origin and intratumoral heterogeneity of PA are largely unknown. Here, we constructed a comprehensive atlas of PA at single-cell resolution and showed that PA exhibited five tumour subpopulations, three recapitulating the epithelial states of the normal parotid gland, and two PA-specific epithelial cell (PASE) populations unique to tumours. Then, six subgroups of PASE cells were identified, which varied in epithelium, bone, immune, metabolism, stemness and cell cycle signatures. Moreover, we revealed that CD36+ myoepithelial cells were the tumour-initiating cells (TICs) in PA, and were dominated by the PI3K-AKT pathway. Targeting the PI3K-AKT pathway significantly inhibited CD36+ myoepithelial cell-derived tumour spheres and the growth of PA organoids. Our results provide new insights into the diversity and origin of PA, offering an important clinical implication for targeting the PI3K-AKT signalling pathway in PA treatment.

Targeting PI3K/Akt signaling in prostate cancer therapy

Urological cancers have obtained much attention in recent years due to their mortality and morbidity. The most common and malignant tumor of urological cancers is prostate cancer that imposes high socioeconomic costs on public life and androgen-deprivation therapy, surgery, and combination of chemotherapy and radiotherapy are employed in its treatment. PI3K/Akt signaling is an oncogenic pathway responsible for migration, proliferation and drug resistance in various cancers. In the present review, the role of PI3K/Akt signaling in prostate cancer progression is highlighted. The activation of PI3K/Akt signaling occurs in prostate cancer, while PTEN as inhibitor of PI3K/Akt shows down-regulation. Stimulation of PI3K/Akt signaling promotes survival of prostate tumor cells and prevents apoptosis. The cell cycle progression and proliferation rate of prostate tumor cells increase by PI3K/Akt signaling induction. PI3K/Akt signaling stimulates EMT and enhances metastasis of prostate tumor cells. Silencing PI3K/Akt signaling impairs growth and metastasis of prostate tumor cells. Activation of PI3K/Akt signaling mediates drug resistance and reduces radio-sensitivity of prostate tumor cells. Anti-tumor compounds suppress PI3K/Akt signaling in impairing prostate tumor progression. Furthermore, upstream regulators such as miRNAs, lncRNAs and circRNAs regulate PI3K/Akt signaling and it has clinical implications for prostate cancer patients.

CD36-BATF2\MYB Axis Predicts Anti-PD-1 Immunotherapy Response in Gastric Cancer

Despite the utilization of anti-PD-1 therapy in gastric cancer (GC), the absence of a reliable predictive biomarker continues to pose a challenge. In this study, we utilized bioinformatic analysis and immunohistochemistry to develop a prediction model for activated CD4+ memory T cells, considering both mRNA and protein levels. An elevation of activated CD4+ memory T cells in GC was noted, which exhibited a strong association with the patients' overall survival. By utilizing WGCNA and DEG analysis, we discovered that BATF2, MYB, and CD36 are genes that exhibit differential expression and are linked to activated CD4+ memory T cells. Afterwards, a forecast model was built utilizing Stepwise regression and immunohistochemistry relying on the three genes. The model's high-risk score showed significant associations with a suppressive immune microenvironment. Moreover, our model exhibited encouraging prognostic value and superior performance in predicting response to immune checkpoint blockade therapy compared with the conventional CD8+PD-L1 model. In terms of mechanism, CD36 could function as a receptor upstream that identifies Helicobacter pylori and fatty acids. This recognition then results in the reduction of the BATF2-MYB protein complex and subsequent alterations in the transcription of genes associated with classical T cell activation. As a result, the activation state of CD4+ memory T cells is ultimately suppressed. The CD36-BATF2/MYB signature serves as a robust predictor of anti-PD-1 immunotherapy response in GC.

Regulatory roles of NAT10 in airway epithelial cell function and metabolism in pathological conditions

N-acetyltransferase 10 (NAT10), a nuclear acetyltransferase and a member of the GNAT family, plays critical roles in RNA stability and translation processes as well as cell proliferation. Little is known about regulatory effects of NAT10 in lung epithelial cell proliferation. We firstly investigated NTA10 mRNA expression in alveolar epithelial types I and II, basal, ciliated, club, and goblet/mucous epithelia from heathy and patients with chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis, lung adenocarcinoma, para-tumor tissue, and systemic sclerosis, respectively. We selected A549 cells for representative of alveolar epithelia or H1299 and H460 cells as airway epithelia with different genetic backgrounds and studied dynamic responses of NAT10-down-regulated epithelia to high temperature, lipopolysaccharide, cigarette smoking extract (CSE), drugs, radiation, and phosphoinositide 3-kinase (PI3K) inhibitors at various doses. We also compared transcriptomic profiles between alveolar and airway epithelia, between cells with or without NAT10 down-regulation, between early and late stages, and between challenges. The present study demonstrated that NAT10 expression increased in human lung epithelia and varied among epithelial types, challenges, and diseases. Knockdown of NAT10 altered epithelial mitochondrial functions, dynamic responses to LPS, CSE, or PI3K inhibitors, and transcriptomic phenomes. NAT10 regulates biological phenomes, and behaviors are more complex and are dependent upon multiple signal pathways. Thus, NAT10-associated signal pathways can be a new alternative for understanding the disease and developing new biomarkers and targets.

Sphingosine kinase 1 regulates lipid metabolism to promote progression of kidney renal clear cell carcinoma

PURPOSE

To detect the expression of sphingosine kinase 1 (SPHK1) in clear cell renal cell carcinoma (ccRCC) and explore its biological role in the occurrence and development of ccRCC through regulation of fatty acid metabolism.

METHODS

Using the Cancer Genome Atlas database, SPHK1 expression and its clinical significance were detected in clear cell renal cell carcinoma. Immunohistochemistry was performed to detect SPHK1 expression in RCC samples in our hospital. The connection between the SPHK1 levels and clinicopathological features of patients was assessed. Nile Red was used to detect fatty acids in cells. Cell Counting Kit-8 and 5-ethynyl-2'-deoxyuridine assays were performed to determine the effect of SPHK1 on renal cell viability and proliferation, respectively. Additionally, the effects of SPHK1 on the proliferation and metastasis of ccRCC were studied using wound healing and Transwell assays. Fatty acids were added exogenously in recovery experiments and western blotting was performed to determine the effect of SPHK1 on fatty acid metabolism in ccRCC. Finally, the effects of SPHK1 on tumor growth were investigated in a xenograft model.

RESULTS

Bioinformatics analysis revealed that SPHK1 expression was upregulated in kidney RCC. OverSPHK1 expression was associated with poor prognosis for ccRCC patients. High SPHK1 expression was detected in human ccRCC. SPHK1 expression was related to clinicopathological features, such as tumor size and Furman grade. Additionally, cell proliferation, migration, and invasion were inhibited in ccRCC cells with low SPHK1 expression. In rescue experiments, proliferation, migration, and invasion were restored. In vivo, reduced SPHK1 levels correlated with lower expression of fatty acid synthase, stearoyl-CoA desaturase 1, and acetyl CoA carboxylase, and slowed tumor growth.

CONCLUSIONS

SPHK1 is abnormally overexpressed in human ccRCC. Patients with ccRCC may benefit from treatments that target SPHK1, which may also serve as a prognostic indicator.

Peritoneal high-fat environment promotes peritoneal metastasis of gastric cancer cells through activation of NSUN2-mediated ORAI2 m5C modification

Peritoneal metastasis (PM) is an important metastatic modality of gastric cancer (GC).It is associated with poor prognosis. The underlying molecular mechanism of PM remains elusive. 5-Methylcytosine (m⁵C), a posttranscriptional RNA modification, involves in the progression of many tumors. However, its role in GC peritoneal metastasis remains unclear. In our study, transcriptome results suggested that NSUN2 expression was significantly upregulated in PM. And patients with high NSUN2 expression of PM predicted a worse prognosis. Mechanistically, NSUN2 regulates ORAI2 mRNA stability by m5C modification, thereby promoting ORAI2 expression and further promoting peritoneal metastasis and colonization of GC. YBX1 acts as a "reader" by binding to the ORAI2 m5C modification site. Following the uptake of fatty acids from omental adipocytes by GC cells, the transcription factor E2F1 was upregulated, which further promoted the expression of NSUN2 through cis-element. Briefly, these results revealed that peritoneal adipocytes provide fatty acid for GC cells, thus contributing to the elevation of E2F1 and NSUN2 through AMPK pathway, and upregulated NSUN2 activates the key gene ORAI2 through m5C modification, thereby promoting peritoneal metastasis and colonization of gastric cancer.

circACTR2 attenuates gemcitabine chemoresiatance in pancreatic cancer through PTEN mediated PI3K/AKT signaling pathway

BACKGROUND

Recently, accumulating studies have unveiled that circRNAs exert critical function in a variety of tumor biological processes including chemoresistance. Our previous study has found circACTR2 is significantly down-regulated in acquired gemcitabine (GEM)- resistant pancreatic cancer (PC) cells, which has not been well-explored. Our study aimed to research the function and molecular mechanism of circACTR2 in PC chemoresistance.

METHODS

qRT-PCR and western blot analysis was performed to detect gene expression. The effect of circACTR2 on PC GEM resistance were examined by CCK-8 and flow cytometry assays. Whether circACTR2 could sponge miR-221-3p and regulate PTEN expression were determined by bioinformatics analysis, RNA pull-down, and Dual-luciferase reporter assay.

RESULTS

circACTR2 was notably down-regulated in a panel of GEM-resistant PC cells lines, and negatively associated with aggressive phenotype and poor prognosis of PC. circACTR2 downregulation contributed to GEM chemoresistance of PC cells with decreased S phase ratio of cell cycle and cell apoptosis, as confirmed by gain- and loss-of-function assays in vitro. In addition, circACTR2 overexpression retarded GEM resistance in vivo. Further, circACTR2 acted as a ceRNA against miR-221-3p, which directly targeted PTEN. The mechanistic studies revealed that loss of circACTR2 promoted GEM resistance in PC through activating the PI3K/AKT signaling pathway by downregulating PTEN expression in a miR-221-3p dependent manner.

CONCLUSIONS

circACTR2 reversed the chemoresistance of PC cells to GEM through inhibiting PI3K/AKT signaling pathway by sponging miR-221-3p and upregulating PTEN expression.

Demethylase FTO enhances the PI3K/Akt signaling to promote gastric cancer malignancy

Enhanced expression of fat mass and obesity-associated protein (FTO) has been reported in gastric cancer (GC). Bioinformatical studies indicate that FTO expression is correlated with the patients' overall survival (OS). How FTO exerts its promotion effects on GC development and affects OS remains largely unknown. In this study, the prognostic relevance of FTO expression in human GC tissues and the molecular mechanisms underlying FTO's promotion roles were investigated. Kaplan-Meier survival curve analysis revealed that the patients with high FTO levels had shorter OS compared to those with low FTO expression (p < 0.0001). Univariate and multivariate COX regression analyses showed that the patients' OS was affected by FTO status (p < 0.0001, p = 0.001, respectively). FTO knockdown in HGC27 cells by shRNAs reduced cell proliferation, colony formation, migration and invasion, while FTO overexpression in AGS cells had reverse effects. FTO knockdown in HGC27 cells also suppressed the tumor growth in a mouse xenograft model. High-throughput transcriptome sequencing indicated that FTO enhanced the PI3K/Akt signaling, which was confirmed in vitro. In summary, our research revealed that FTO is a potent prognostic biomarker of GC. FTO enhances the PI3K/Akt signaling and thus, promotes GC development.

Comprehensive in-silico analysis of deleterious SNPs in APOC2 and APOA5 and their differential expression in cancer and cardiovascular diseases conditions

Genetic variations in APOC2 and APOA5 genes involve activating lipoprotein lipase (LPL), responsible for the hydrolysis of triglycerides (TG) in blood and whose impaired functions affect the TG metabolism and are associated with metabolic diseases. In this study, we investigate the biological significance of genetic variations at the DNA sequence and structural level using various computational tools. Subsequently, 8 (APOC2) and 17 (APOA5) non-synonymous SNPs (nsSNPs) were identified as high-confidence deleterious SNPs based on the effects of the mutations on protein conservation, stability, and solvent accessibility. Furthermore, based on our docking results, the interaction of native and mutant forms of the corresponding proteins with LPL depicts differences in root mean square deviation (RMSD), and binding affinities suggest that these mutations may affect their function. Furthermore, in vivo, and in vitro studies have shown that differential expression of these genes in disease conditions due to the influence of nsSNPs abundance may be associated with promoting the development of cancer and cardiovascular diseases. Preliminary screening using computational methods can be a helpful start in understanding the effects of mutations in APOC2 and APOA5 on lipid metabolism; however, further wet-lab experiments would further strengthen the conclusions drawn from the computational study.

Prognostic effects of the gastric mucosal microbiota in gastric cancer

Gastric cancer (GC) is one of the most common malignant tumors with a high incidence and mortality. Microbiota play a significant role in human health and disease. We aimed to investigate the prognostic value of the gastric microbiota in different stomach microhabitats. We used our previously published 16S rRNA gene sequence data. We retrospectively enrolled a cohort of 132 patients with GC with complete prognostic information and selected 78 normal tissues, 49 peritumoral tissues, and 112 tumoral tissues for microbiota analysis. Patients with different prognoses showed different gastric microbiota compositions and diversity. The association network of the abundant gastric microbiota was more complicated in patients with poor prognoses. In the peritumoral microhabitat of patients with good prognoses, Helicobacter was significantly increased, whereas Halomonas and Shewanella were significantly decreased relative to that in the peritumoral microhabitat of patients with poor prognoses. PiCRUSt analysis revealed that the peritumoral microbiota had more different Kyoto Encyclopedia of Genes and Genomes pathways than did the tumoral and normal microbiota. This study evaluated the long-term prognostic value of the gastric mucosal microbiota in patients with GC. These findings suggested that the characteristic alterations of the gastric mucosal microbiota may be markers for clinical outcomes in these patients.

Construction of a nomogram model for predicting peritoneal metastasis in gastric cancer: focused on cardiophrenic angle lymph node features

BACKGROUND

A different treatment was used when peritoneal metastases (PM) occurred in patients with gastric cancer (GC). Certain cancers' peritoneal metastasis could be predicted by the cardiophrenic angle lymph node (CALN). This study aimed to establish a predictive model for PM of gastric cancer based on the CALN.

METHODS

Our center retrospectively analyzed all GC patients between January 2017 and October 2019. Pre-surgery computed tomography (CT) scans were performed on all patients. The clinicopathological and CALN features were recorded. PM risk factors were identified via univariate and multivariate logistic regression analyses. The receiver operator characteristic (ROC) curves were generated using these CALN values. Using the calibration plot, the model fit was assessed. A decision curve analysis (DCA) was conducted to assess the clinical utility.

RESULTS

126 of 483 (26.1%) patients were confirmed as having peritoneal metastasis. These relevant factors were associated with PM: age, sex, T stage, N stage, enlarged retroperitoneal lymph nodes (ERLN), CALN, the long diameter of the largest CALN (LD of LCALN), the short diameter of the largest CALN (SD of LCALN), and the number of CALNs (N of CALNs). The multivariate analysis illustrated that the LD of LCALN (OR = 2.752, p < 0.001) was PM's independent risk factor in GC patients. The area under the curve (AUC) of the model was 0.907 (95% CI 0.872-0.941), demonstrating good performance in the predictive value of PM. There is excellent calibration evident from the calibration plot, which is close to the diagonal. The DCA was presented for the nomogram.

CONCLUSION

CALN could predict gastric cancer peritoneal metastasis. The model in this study provided a powerful predictive tool for determining PM in GC patients and helping clinicians allocate treatment.

Identification and validation of crucial lnc-TRIM28-14 and hub genes promoting gastric cancer peritoneal metastasis

BACKGROUND

Gastric cancer peritoneal metastasis (GCPM) is an important cause of cancer-related deaths worldwide. Long non-coding RNAs (lncRNAs) play a key role in the regulation of GCPM, but the underlying mechanisms have not been elucidated.

METHODS

High-throughput RNA sequencing (RNA-seq) was performed on four groups of clinical specimens (non-metastatic gastric cancer primary tumor, adjacent normal gastric mucosal tissue, gastric cancer primary tumor with peritoneal metastasis and adjacent normal gastric mucosal tissue). After sequencing, many lncRNAs and mRNAs were screened for further Weighted Gene Co-expression Network Analysis (WGCNA). GCPM-related hub lncRNAs and genes were identified by cytoHubba and validated by Quantitative real-time PCR (qRT-PCR), Receiver operating characteristic curve (ROC) analysis and Kaplan-Meier survival analysis. GO, KEGG and GSEA showed GCPM-related pathways. Correlation analysis revealed the potential relationship between hub lncRNAs and genes.

RESULTS

By analyzing lncRNA expression data by WGCNA, we found that blue module was highly correlated with GCPM (r = 0.44, p = 0.04) and six lncRNAs involved in this module (DNM3OS, lnc-MFAP2-53, lnc-PPIAL4C-4, lnc-RFNG-1, lnc-TRIM28-14 and lnc-YARS2-4) were identified. We then performed qRT-PCR validation of gastric cancer specimens and found that the expression of lnc-RFNG-1 and lnc-TRIM28-14 was significantly increased in gastric cancer tissues with peritoneal metastasis. Kaplan-Meier survival analysis showed shorter overall survival time (OS) for gastric cancer patients with high expression of lnc-TRIM28-14. Receiver operating characteristic curve (ROC) analysis showed that lnc-TRIM28-14 could improve the sensitivity and specificity of GCPM diagnosis. In addition, we identified three key mRNAs (CD93, COL3A1 and COL4A1) associated with gastric cancer peritoneal metastasis through WGCNA analysis and clinical specimen validation. Moreover, there was a positive correlation between lnc-TRIM28-14 and the expression of CD93 and COL4A1 in gastric cancer peritoneal metastasis, suggesting a regulatory relationship between them. Subsequent GO, KEGG and GSEA analysis suggested that ECM-receptor interaction and focal adhesion were the hub pathways of GCPM.

CONCLUSION

In summary, lnc-RFNG-1, lnc-TRIM28-14, CD93, COL3A1 and COL4A1 could be novel tumor biomarkers and potential therapeutic targets for GCPM.

Characterization of lipid droplet metabolism patterns identified prognosis and tumor microenvironment infiltration in gastric cancer

Background

Gastric cancer is one of the common malignant tumors of the digestive system worldwide, posing a serious threat to human health. A growing number of studies have demonstrated the important role that lipid droplets play in promoting cancer progression. However, few studies have systematically evaluated the role of lipid droplet metabolism-related genes (LDMRGs) in patients with gastric cancer.

Methods

We identified two distinct molecular subtypes in the TCGA-STAD cohort based on LDMRGs expression. We then constructed risk prediction scoring models in the TCGA-STAD cohort by lasso regression analysis and validated the model with the GSE15459 and GSE66229 cohorts. Moreover, we constructed a nomogram prediction model by cox regression analysis and evaluated the predictive efficacy of the model by various methods in STAD. Finally, we identified the key gene in LDMRGs, ABCA1, and performed a systematic multi-omics analysis in gastric cancer.

Results

Two molecular subtypes were identified based on LDMRGs expression with different survival prognosis and immune infiltration levels. lasso regression models were effective in predicting overall survival (OS) of gastric cancer patients at 1, 3 and 5 years and were validated in the GEO database with consistent results. The nomogram prediction model incorporated additional clinical factors and prognostic molecules to improve the prognostic predictive value of the current TNM staging system. ABCA1 was identified as a key gene in LDMRGs and multi-omics analysis showed a strong correlation between ABCA1 and the prognosis and immune status of patients with gastric cancer.

Conclusion

This study reveals the characteristics and possible underlying mechanisms of LDMRGs in gastric cancer, contributing to the identification of new prognostic biomarkers and providing a basis for future research.

Apolipoproteins: New players in cancers

Apolipoproteins (APOs), the primary protein moiety of lipoproteins, are known for their crucial role in lipid traffic and metabolism. Despite extensive exploration of APOs in cardiovascular diseases, their roles in cancers did not attract enough attention. Recently, research focusing on the roles of APOs in cancers has flourished. Multiple studies demonstrate the interaction of APOs with classical pathways of tumorigenesis. Besides, the dysregulation of APOs may indicate cancer occurrence and progression, thus serving as potential biomarkers for cancer patients. Herein, we summarize the mechanisms of APOs involved in the development of various cancers, their applications as cancer biomarkers and their genetic polymorphism associated with cancer risk. Additionally, we also discuss the potential anti-cancer therapies by virtue of APOs. The comprehensive review of APOs in cancers may advance the understanding of the roles of APOs in cancers and their potential mechanisms. We hope that it will provide novel clues and new therapeutic strategies for cancers.

CD36 and Its Role in Regulating the Tumor Microenvironment

CD36 is a transmembrane glycoprotein that binds to a wide range of ligands, including fatty acids (FAs), cholesterol, thrombospondin-1 (TSP-1) and thrombospondin-2 (TSP-2), and plays an important role in lipid metabolism, immune response, and angiogenesis. Recent studies have highlighted the role of CD36 in mediating lipid uptake by tumor-associated immune cells and in promoting tumor cell progression. In cancer-associated fibroblasts (CAFs), CD36 regulates lipid uptake and matrix protein production to promote tumor proliferation. In addition, CD36 can promote tumor cell adhesion to the extracellular matrix (ECM) and induce epithelial mesenchymal transition (EMT). In terms of tumor angiogenesis, CD36 binding to TSP-1 and TSP-2 can both inhibit tumor angiogenesis and promote tumor migration and invasion. CD36 can promote tumor angiogenesis through vascular mimicry (VM). Overall, we found that CD36 exhibits diverse functions in tumors. Here, we summarize the recent research findings highlighting the novel roles of CD36 in the context of tumors.

Integrative analysis of the proteome and transcriptome in gastric cancer identified LRP1B as a potential biomarker

Background: The aim of this study was to discover unique membrane proteins associated with gastric cancer (GC) in proteomics analysis. Methods: Using a data-independent acquisition strategy, we compared the relative expression levels of membrane proteins in GC. Results: A total of 2774 differentially expressed membrane proteins were identified between GC and normal cell lines. Conjoint analysis of transcriptomes and proteomes provided 11 potential biomarkers (GPRC5A, PSAT1, NUDCD1, RCC2, IPO4, FAM91A1, KANK2, PRADC1, NME4, METTL7A and LRP1B) for further exploration. Downregulation of LRP1B in GC was validated by immunohistochemistry. Moreover, LRP1B demonstrated an area under the receiver operating characteristic curve of 0.917 in differentiating GC from normal tissues. Conclusion: LRP1B was identified as a meaningful indicator assisting in GC detection and labeling of tumor boundaries.

Molecular biology of pancreatic neuroendocrine tumors: From mechanism to translation

Pancreatic neuroendocrine tumors (pNETs) are a group of heterogeneous tumors originated from progenitor cells. As these tumors are predominantly non-functional, most of them display asymptomatic characteristics, making it difficult to be realized from early onset. Therefore, patients with pNETs are usually diagnosed with metastatic disease or at a late disease stage. The relatively low incidence also limits our understanding of the biological background of pNETs, which largely impair the development of new effective drugs. The fact that up to 10% of pNETs develop in patients with genetic syndromes have promoted researchers to focus on the gene mutations and driver mutations in MEN1, DAXX/ATRX and mTOR signaling pathway genes have been implicated in disease development and progression. Recent advances in sequencing technologies have further enriched our knowledge of the complex molecular landscape of pNETs, pointing out crucial roles of genes in DNA damage pathways, chromosomal and telomere alterations and epigenetic dysregulation. These novel findings may not only benefit early diagnosis of pNETs, but also help to uncover tumor heterogeneity and shape the future of translational medical treatment. In this review, we focus on the current molecular biology of pNETs and decipher how these findings may translate into future development of targeted therapy.

Emerging Roles of Lipophagy in Cancer Metastasis

Simple Summary

Metastasis is the main cause of death in patients with malignant tumors worldwide. Mounting evidence suggests lipid droplet metabolism is involved in the process of metastasis. As a mechanism to selectively degrade lipid droplets, the current research on lipophagy and tumor metastasis is quite limited. This review summarizes the crosstalk among lipophagy, tumor lipid metabolism and cancer metastasis, which will provide a new reference for the development of effective targeted drugs.

Abstract

Obesity is a prominent risk factor for certain types of tumor progression. Adipocytes within tumor stroma contribute to reshaping tumor microenvironment (TME) and the metabolism and metastasis of tumors through the production of cytokines and adipokines. However, the crosstalk between adipocytes and tumor cells remains a major gap in this field. Known as a subtype of selective autophagy, lipophagy is thought to contribute to lipid metabolism by breaking down intracellular lipid droplets (LDs) and generating free fatty acids (FAs). The metastatic potential of cancer cells closely correlates with the lipid degradation mechanisms, which are required for energy generation, signal transduction, and biosynthesis of membranes. Here, we discuss the recent advance in the understanding of lipophagy with tumor lipid metabolism and review current studies on the roles of lipoghagy in the metastasis of certain human malignancies. Additionally, the novel candidate drugs targeting lipophagy are integrated for effective treatment strategies.

Cell death affecting the progression of gastric cancer

Gastric cancer is a gastrointestinal tumor with high morbidity and mortality rates. Several factors influence its progression, cell death being an important element. In this review, we summarized the effects of necrosis, apoptosis, necroptosis, pyroptosis, ferroptosis, and eight less common cell death modalities on gastric cancer cells and the tumor microenvironment, detailed the molecular mechanisms of various cell death and their major regulatory pathways in gastric cancer, explored the prevalence and complexity of cell death in gastric cancer progression and highlighted the potentials of cell death-related therapies in gastric cancer.

Curcuminoids as Modulators of EMT in Invasive Cancers: A Review of Molecular Targets With the Contribution of Malignant Mesothelioma Studies

Curcuminoids, which include natural acyclic diarylheptanoids and the synthetic analogs of curcumin, have considerable potential for fighting against all the characteristics of invasive cancers. The epithelial-to-mesenchymal transition (EMT) is a fundamental process for embryonic morphogenesis, however, the last decade has confirmed it orchestrates many features of cancer invasiveness, such as tumor cell stemness, metabolic rewiring, and drug resistance. A wealth of studies has revealed EMT in cancer is in fact driven by an increasing number of parameters, and thus understanding its complexity has now become a cornerstone for defining future therapeutic strategies dealing with cancer progression and metastasis. A specificity of curcuminoids is their ability to target multiple molecular targets, modulate several signaling pathways, modify tumor microenvironments and enhance the host’s immune response. Although the effects of curcumin on these various parameters have been the subject of many reviews, the role of curcuminoids against EMT in the context of cancer have never been reviewed so far. This review first provides an updated overview of all EMT drivers, including signaling pathways, transcription factors, non-coding RNAs (ncRNAs) and tumor microenvironment components, with a special focus on the most recent findings. Secondly, for each of these drivers the effects of curcumin/curcuminoids on specific molecular targets are analyzed. Finally, we address some common findings observed between data reported in the literature and the results of investigations we conducted on experimental malignant mesothelioma, a model of invasive cancer representing a useful tool for studies on EMT and cancer.

Lipids and genes: Regulatory roles of lipids in RNA expression

Nuclear lipid metabolism and metabolites play important roles in regulation of lipid-lipid, lipid-gene, lipid-chromatin, lipid-membrane and lipid-protein interactions to maintain the nuclear microenvironment, three-dimensional chromatin architecture, gene expression and transcription and biological function. This Editorial highlights the value of lipid-gene interaction in the identification and development of biomarkers and targets and emphasizes the significance of inter-regulation between lipids and genes in innovation and application of precise therapies for patients. Regulatory functions of nuclear lipid dynamics and biophysics modify transcriptomic expression, and modification (lipotranscriptome) can be a new approach for discovery and development of disease-specific diagnoses and therapies, although there are several challenges to be overcome. Better understanding of how lipid-based changes of nuclear functions and transcriptomic profiles modify clinical phenomes will provide new insights to understand molecular mechanisms of diseases and to develop spatiotemporal molecular medicine diagnostics and therapeutics.

Identification of Immune Subtypes of Esophageal Adenocarcinoma to Predict Prognosis and Immunotherapy Response

A low response rate limits the application of immune checkpoint inhibitors (ICIs) in the treatment of esophageal adenocarcinoma (EAC), which requires the precise characterization of heterogeneous tumor microenvironments. This study aimed to identify the molecular features and tumor microenvironment compositions of EAC to facilitate patient stratification and provide novel strategies to improve clinical outcomes. Here, we performed consensus molecular subtyping with nonnegative matrix factorization (NMF) using EAC data from the Cancer Genome Atlas (TCGA) and identified two distinct subtypes with significant prognostic differences and differences in tumor microenvironments. The findings were further validated in independent EAC cohorts and potential response to ICI therapy was estimated using Tumor Immune Dysfunction and Exclusion (TIDE) and SubMap methods. Our findings suggest that EAC patients of subtype 2 with low levels of cancer-associated fibroblasts, tumor associated macrophages (TAMs), and MDSCs in the tumor microenvironment may benefit from PD-1 blockade therapy, while patients of subtype 1 are more responsive to chemotherapy or combination therapy. These findings might improve our understanding of immunotherapy efficacy and be useful in the development of new strategies to better guide immunotherapy and targeted therapy in the treatment of EAC.

Stanniocalcin 1 promotes metastasis, lipid metabolism and cisplatin chemoresistance via the FOXC2/ITGB6 signaling axis in ovarian cancer

BACKGROUND

Stanniocalcin 1 (STC1) plays an integral role in ovarian cancer (OC). However, the functional role of STC1 in metastasis, lipid metabolism and cisplatin (DDP) chemoresistance in OC is not fully understood.

METHODS

Single-cell sequencing and IHC analysis were performed to reveal STC1 expression profiles in patient tissues. Metastasis, lipid metabolism and DDP chemoresistance were subsequently assessed. Cell-based in vitro and in vivo assays were subsequently conducted to gain insight into the underlying mechanism of STC1 in OC.

RESULTS

Single-cell sequencing assays and IHC analysis verified that STC1 expression was significantly enhanced in OC tissues compared with para-carcinoma tissues, and it was further up-regulated in peritoneal metastasis tissues compared with OC tissues. In vitro and in vivo experiments demonstrated that STC1 promoted metastasis, lipid metabolism and DDP chemoresistance in OC. Simultaneously, STC1 promoted lipid metabolism by up-regulating lipid-related genes such as UCP1, TOM20 and perilipin1. Mechanistically, STC1 directly bound to integrin β6 (ITGB6) to activate the PI3K signaling pathway. Moreover, STC1 was directly regulated by Forkhead box C2 (FOXC2) in OC. Notably, targeting STC1 and the FOXC2/ITGB6 signaling axis was related to DDP chemoresistance in vitro.

CONCLUSIONS

Overall, these findings revealed that STC1 promoted metastasis, lipid metabolism and DDP chemoresistance via the FOXC2/ITGB6 signaling axis in OC. Thus, STC1 may be used as a prognostic indicator in patients with metastatic OC. Meanwhile, STC1 could be a therapeutic target in OC patients, especially those who have developed chemoresistance to DDP.

TRAM2 promotes the malignant progression of glioma through PI3K/AKT/mTOR pathway

Molecular biomarkers play an important guidance role in the diagnosis and treatment of glioma. It has been found that TRAM2 (translocation associated membrane protein 2) drives human cancers development. Here we report that TRAM2 activity is required for malignancy properties of glioma. In this study, we demonstrated that TRAM2 is over-expressed in glioma and cell lines, particularly in the mesenchymal subtype, and glioma patients with high expression of TRAM2 is associated with poorer survival. Silencing of TRAM2 significantly suppresses glioma cell proliferation, invasion, migration and EMT in vitro, and inhibits tumorigenicity of glioma cell in vivo. We further identify that TRAM2 is positively associated with activation of the PI3K/AKT/mTOR signaling in glioma. 740Y-P, a PI3K activator, reversed the effects of TRAM2 silencing on glioma cell proliferation, invasion, migration and EMT process. Taken together, these findings establish that TRAM2/PI3K/AKT/mTOR signaling drives malignancy properties of glioma and indicate that TRAM2 may act as a potential therapeutic target for glioma.

Tumor metastasis: Mechanistic insights and therapeutic interventions

Cancer metastasis is responsible for the vast majority of cancer-related deaths worldwide. In contrast to numerous discoveries that reveal the detailed mechanisms leading to the formation of the primary tumor, the biological underpinnings of the metastatic disease remain poorly understood. Cancer metastasis is a complex process in which cancer cells escape from the primary tumor, settle, and grow at other parts of the body. Epithelial-mesenchymal transition and anoikis resistance of tumor cells are the main forces to promote metastasis, and multiple components in the tumor microenvironment and their complicated crosstalk with cancer cells are closely involved in distant metastasis. In addition to the three cornerstones of tumor treatment, surgery, chemotherapy, and radiotherapy, novel treatment approaches including targeted therapy and immunotherapy have been established in patients with metastatic cancer. Although the cancer survival rate has been greatly improved over the years, it is still far from satisfactory. In this review, we provided an overview of the metastasis process, summarized the cellular and molecular mechanisms involved in the dissemination and distant metastasis of cancer cells, and reviewed the important advances in interventions for cancer metastasis.