Vitamin B6 deficiency cooperates with oncogenic Ras to induce malignant tumors in Drosophila.

Vitamin B6 is a water-soluble vitamin which possesses antioxidant properties. Its catalytically active form, pyridoxal 5'-phosphate (PLP), is a crucial cofactor for DNA and amino acid metabolism. The inverse correlation between vitamin B6 and cancer risk has been observed in several studies, although dietary vitamin B6 intake sometimes failed to confirm this association. However, the molecular link between vitamin B6 and cancer remains elusive. Previous work has shown that vitamin B6 deficiency causes chromosome aberrations (CABs) in Drosophila and human cells, suggesting that genome instability may correlate the lack of this vitamin to cancer. Here we provide evidence in support of this hypothesis. Firstly, we show that PLP deficiency, induced by the PLP antagonists 4-deoxypyridoxine (4DP) or ginkgotoxin (GT), promoted tumorigenesis in eye larval discs transforming benign RasV12 tumors into aggressive forms. In contrast, PLP supplementation reduced the development of tumors. We also show that low PLP levels, induced by 4DP or by silencing the sgllPNPO gene involved in PLP biosynthesis, worsened the tumor phenotype in another Drosophila cancer model generated by concomitantly activating RasV12 and downregulating Discs-large (Dlg) gene. Moreover, we found that RasV12 eye discs from larvae reared on 4DP displayed CABs, reactive oxygen species (ROS) and low catalytic activity of serine hydroxymethyltransferase (SHMT), a PLP-dependent enzyme involved in thymidylate (dTMP) biosynthesis, in turn required for DNA replication and repair. Feeding RasV12 4DP-fed larvae with PLP or ascorbic acid (AA) plus dTMP, rescued both CABs and tumors. The same effect was produced by overexpressing catalase in RasV12 DlgRNAi 4DP-fed larvae, thus allowing to establish a relationship between PLP deficiency, CABs, and cancer. Overall, our data provide the first in vivo demonstration that PLP deficiency can impact on cancer by increasing genome instability, which is in turn mediated by ROS and reduced dTMP levels.

Orbea variegata (L.) Haw in skin carcinogenesis: insights from an in vivo male Swiss mouse model study.

Skin cancer is the most widespread type of malignant tumor representing a major public health concern. Considering the numerous side effects associated with conventional treatments, phytotherapy may be regarded as a viable medicinal alternative. This study aimed to investigate the therapeutic potential of Orbea variegata (L.) Haw, an ornamental plant, in treating skin cancer using an animal model induced by a combination of ultraviolet (UV) irradiation and sulfuric acid treatment. The hydroethanolic extract of Orbea variegata underwent phytochemical characterization, identifying the presence of reducing sugars, coumarins, alkaloids, flavonoids, tannins, and saponins through qualitative screening. Quantitative analysis demonstrated significant amounts of phenolic compounds (29.435 ± 0.571 mg GAE/g of dry extract), flavonoids (6.711 ± 0.272 mg QE/g of dry extract), and tannins (274.037 ± 11.3 mg CE/g of dry extract). The administration the hydroethanolic extract in two concentrations (1 or 2 g/kg) to male Swiss mice exhibited no marked adverse effects, as evidenced by serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) enzyme activity levels. In addition, the extract significantly reduced skin hyperplasia and inflammation induced by UV/sulfuric acid treatment as noted in tissue analyses and decreased protein expression of nuclear proliferation marker (Ki-67). This improvement was associated with a marked decrease in oxidative stress, as indicated by diminished lipid peroxidation levels, and restoration of the activity of endogenous antioxidant enzyme catalase (CAT) to control levels. Our findings demonstrated the potential of Orbea variegata hydroethanolic extract to be considered as a treatment for skin cancer, exhibiting its apparent safety and efficacy in reducing inflammation and carcinogenesis in a UV/sulfuric acid-induced Swiss mouse model, attributed to its phytochemical content and associated antioxidant activities.

Antiviral Shrimp lncRNA06 Possesses Anti-Tumor Activity by Inducing Apoptosis of Human Gastric Cancer Stem Cells in a Cross-Species Manner.

Virus infection causes the metabolic disorder of host cells, whereas the metabolic disorder of cells is one of the major causes of tumorigenesis, suggesting that antiviral molecules might possess anti-tumor activities by regulating cell metabolism. As the key regulators of gene expression, long non-coding RNAs (lncRNAs) play vital roles in the regulation of cell metabolism. However, the influence of antiviral lncRNAs on tumorigenesis has not been explored. To address this issue, the antiviral and anti-tumor capacities of shrimp lncRNAs were characterized in this study. The results revealed that shrimp lncRNA06, having antiviral activity in shrimp, could suppress the tumorigenesis of human gastric cancer stem cells (GCSCs) via triggering apoptosis of GCSCs in a cross-species manner. Shrimp lncRNA06 could sponge human miR-17-5p to suppress the stemness of GCSCs via the miR-17-5p-p21 axis. At the same time, shrimp lncRNA06 could bind to ATP synthase subunit beta (ATP5F1B) to enhance the stability of the ATP5F1B protein in GCSCs, thus suppressing the tumorigenesis of GCSCs. The in vivo data demonstrated that shrimp lncRNA06 promoted apoptosis and inhibited the stemness of GCSCs through interactions with ATP5F1B and miR-17-5p, leading to the suppression of the tumorigenesis of GCSCs. Therefore, our findings highlighted that antiviral lncRNAs possessed anti-tumor capacities and that antiviral lncRNAs could be the anti-tumor reservoir for the treatment of human cancers.

(NDMA) METFORMIN AND (NTTP) SITAGLIPTIN INDUCED CUTANEOUS MELANOMAS: LINKS TO NITROSOGENESIS, NITROSO-PHOTOCARCINOGENESIS, ONCOPHARMACOGENESIS AND THE METABOLIC REPROGRAMMING.

Changing the vision, understanding, interpretation and analysis of certain data or scientific dilemmas is what is able to change the status quo and revitalize a mission, an impulse or important thoughts, thus creating the conditions for it to increase immensely the chances of bringing it to success. Or, following Albert Einstein's postulate: ˝We cannot solve our problems with the same thinking we used when we created them˝, we should think: ˝Where does the road to success start? How do we solve or neutralize a problem? ˝ And the answer is: ˝ By taking a consistent and systematic approach, analyzing each component! And we eliminate every possibility of negative influence.˝ These thoughts apply with full force to cancer rates in general, but also to melanoma rates in particular: the murderous tempo of globalization and modernization in medicine has not yet led to the desired decrease in these rates; on the contrary, they are rising headlong and remain largely unpredictable and difficult to regulate. The conclusion is that a solution should be sought by refracting light through another prism: that of Nitrosogenesis and Pharmaco-Oncogenesis. A step-by-step and systematic approach to solving a problem requires patience, determination, and perseverance. As this perseverance is needed mainly to overcome the general ignorance, neglect, disinterest, uneducation and uncertainty of others, rather than doubt in one's own thesis, analysis, and the need for an active approach. Careful analysis of concepts such as ˝Drug Mediated Nitrosogenesis˝ and ˝Onco-pharmacogenesis/Pharmaco-oncogenesis˝ of skin cancer would certainly contribute to the elucidation of skin carcinogenesis in the context of polymedication of the contamination and polymorbidity worldwide. The FDA has already in 2019 taken this much needed first step of universal awareness and its ˝arm˝ has been taken seriously and responsibly solely by dermatologists and dermatosurgeons. It was this guild and only this guild that launched its independent, never-ending observations, logically grounded (hypo)theses, remaining to date confirmatory, unshakable, and enigmatic regarding the unit: intake of potentially contaminated medication and subsequent development of melanomas. It is this and only this branch of the medical guild that has also become the guarantor of safety and objectivity in science, and thus of safety in the fight for survival of a huge number of skin cancer patients. Contaminated oral antidiabetic drugs in the face of Metformin and Sitagliptin do not make an exception in this respect. Similarly to cutaneous melanomas occurring (and published in the scientific literature) after combined intake (or monomedication) of/ between ranitidine, valsartan, olmesartan, candesartan, telmisartan, irbesartan, losartan, enalapril, lisinopril, perindopril, hydrochlorothiazide, nifedipine, amlodipine, propafenone, bisoprolol, nebivolol, melitracen and a number of others, we inform about another rare but not unexpected clinical observation: occurrence of cutaneous melanomas after taking another class of drugs- oral antidiabetic ones. Or after the intake of nitrosamine-contaminated antidiabetic drugs. And whether this contamination is "real or potential" is left to regulators and manufacturers to decide. We accept it as `real-potential' or `potentially-real' because of the fact that neither the regulators nor the manufacturers know what it is or whether it is there or how it arose. The data shared in patients one and two in the presented scientific work are confirmatory in relation to the potential pathogenetic action of nitrosamine contaminated drugs such as 1) bisoprolol/ nebivolol/ candesartan/ hydrochlorothiazide and amlodipine, as well as 2) furosemide in the direction of cutaneous melanoma. Patient 3 in fact also represents the first formally described patient with subsequent melanoma development worldwide, having developed it following intake of potentially/actually nitrosamine-contaminated metformin and metformin/sitagliptin (both drugs are themed in the FDA's Potentially Contaminated Drug Bulletin: 1) metformin, multiple times between 2020-21, due to its contamination with NDMA and 2) sitagliptin, as of September 2022, due to its contamination with NTTP). It should not be seen as surprising to anyone that the intake of relatively similar carcinogens/nitrosamines or NDSRIs, but as an unofficial component of heterogeneous drugs, produces a relatively monomorphic clinical picture- that of cutaneous melanoma. Or to put it metaphorically: ˝The wolf changes its hair, but not its mood˝. A carcinogen remains a carcinogen, regardless of whether it is ingested in a lemonade, a tablet, a sandwich, or a bonbon. Similarly to the intake of nitrosamines in food. Future studies should address the important tasks/dilemmas to elucidate 1) the phototoxic/photocarcinogenic effect of unmetabolized nitrosamines identified in drug formulations; 2) the phototoxic/photocarcinogenic effect of DNA adducts generated after their metabolization, and 3) the availability of specific DNA adducts in lesional/tumor tissue and blood of patients after ingestion of nitroso-containing drug formulations. This level of evidence is likely to lead to a reconsideration of the arguments for the introduction of permanent elimination regimes for nitrosamines in medicines. Metabolic reprogramming (and its relationship to UVB radiation) due to the availability of nitrosamines in cigarette smoke is also currently a proven reality. Based on the available clinicopathological correlations, we believe that nitrosamines in drugs have a similar effect and are part of the key pathway activating skin carcinogenesis under the influence of solar radiation. Intake of contaminated medication is associated with skin cancer generation and progression. It is up to regulators and manufacturers to justify the merits and benefits of the self-imposed presence of carcinogens in drugs or the benefits of such drugs. Apart from the "cancer-generating benefit", of course, which is already widely known. And let us not forget that: "A lie stops being a lie and becomes a truth the moment it is officially refuted".

Toxicology and carcinogenesis study of triclosan administered dermally to B6C3F1/N mice.

Triclosan is a broad-spectrum antimicrobial agent to which humans are widely exposed. Very limited data are available regarding the dermal toxicity and the carcinogenic potential of triclosan. In this study, groups of 48 male and 48 female B6C3F1/N mice were untreated or were dermally administered 0 (vehicle), 1.25, 2.7, 5.8, or 12.5 mg triclosan/kg body weight/day (mg/kg/day) in 95% ethanol, 7 days per week for 2 years. Vehicle control animals received 95% ethanol only; untreated, naive control mice were not dosed. There were no significant differences in survival among the groups. The highest dose of triclosan decreased the body weights of mice in both sexes, but the decrease was ≤8%. (Abstract Abridged).

Bifidobacterium breve-derived indole-3-lactic acid ameliorates colitis-associated tumorigenesis by directing the differentiation of immature colonic macrophages.

Aim: To elucidate dynamics and functions in colonic macrophage subsets, and their regulation by Bifidobacterium breve (B. breve) and its associated metabolites in the initiation of colitis-associated colorectal cancer (CAC). Methods: Azoxymethane (AOM) and dextran sodium sulfate (DSS) were used to create a CAC model. The tumor-suppressive effect of B. breve and variations of macrophage subsets were evaluated. Intestinal macrophages were ablated to determine their role in the protective effects of B. breve. Efficacious molecules produced by B. breve were identified by non-targeted and targeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The molecular mechanism was further verified in murine bone marrow-derived macrophages (BMDMs), macrophages derived from human peripheral blood mononuclear cells (hPBMCs), and demonstrated in CAC mice. Results: B. breve alleviated colitis symptoms, delayed colonic tumorigenesis, and promoted phenotypic differentiation of immature inflammatory macrophages into mature homeostatic macrophages. On the contrary, the ablation of intestinal macrophages largely annulled the protective effects of B. breve. Microbial analysis of colonic contents revealed the enrichment of probiotics and the depletion of potential pathogens following B. breve supplementation. Moreover, indole-3-lactic acid (ILA) was positively correlated with B. breve in CAC mice and highly enriched in the culture supernatant of B. breve. Also, the addition of ILA directly promoted AKT phosphorylation and restricted the pro-inflammatory response of murine BMDMs and macrophages derived from hPBMCs in vitro. The effects of ILA in murine BMDMs and macrophages derived from hPBMCs were abolished by the aryl hydrocarbon receptor (AhR) antagonist CH-223191 or the AKT inhibitor MK-2206. Furthermore, ILA could protect against tumorigenesis by regulating macrophage differentiation in CAC mice; the AhR antagonist largely abrogated the effects of B. breve and ILA in relieving colitis and tumorigenesis. Conclusion: B. breve-mediated tryptophan metabolism ameliorates the precancerous inflammatory intestinal milieu to inhibit tumorigenesis by directing the differentiation of immature colonic macrophages.

CRISPR-Cas9 library screening combined with an exosome-targeted delivery system addresses tumorigenesis/TMZ resistance in the mesenchymal subtype of glioblastoma.

Rationale: The large-scale genomic analysis classifies glioblastoma (GBM) into three major subtypes, including classical (CL), proneural (PN), and mesenchymal (MES) subtypes. Each of these subtypes exhibits a varying degree of sensitivity to the temozolomide (TMZ) treatment, while the prognosis corresponds to the molecular and genetic characteristics of the tumor cell type. Tumors with MES features are predominantly characterized by the NF1 deletion/alteration, leading to sustained activation of the RAS and PI3K-AKT signaling pathways in GBM and tend to acquire drug resistance, resulting in the worst prognosis compared to other subtypes (PN and CL). Here, we used the CRISPR/Cas9 library screening technique to detect TMZ-related gene targets that might play roles in acquiring drug resistance, using overexpressed KRAS-G12C mutant GBM cell lines. The study identified a key therapeutic strategy to address the chemoresistance against the MES subtype of GBM. Methods: The CRISPR-Cas9 library screening was used to discover genes associated with TMZ resistance in the U87-KRAS (U87-MG which is overexpressed KRAS-G12C mutant) cells. The patient-derived GBM primary cell line TBD0220 was used for experimental validations in vivo and in vitro. Chromatin isolation by RNA purification (ChIRP) and chromatin immunoprecipitation (ChIP) assays were used to elucidate the silencing mechanism of tumor suppressor genes in the MES-GBM subtype. The small-molecule inhibitor EPIC-0412 was obtained through high-throughput screening. Transmission electron microscopy (TEM) was used to characterize the exosomes (Exos) secreted by GBM cells after TMZ treatment. Blood-derived Exos-based targeted delivery of siRNA, TMZ, and EPIC-0412 was optimized to tailor personalized therapy in vivo. Results: Using the genome-wide CRISPR-Cas9 library screening, we found that the ERBIN gene could be epigenetically regulated in the U87-KRAS cells. ERBIN overexpression inhibited the RAS signaling and downstream proliferation and invasion effects of GBM tumor cells. EPIC-0412 treatment inhibited tumor proliferation and EMT progression by upregulating the ERBIN expression both in vitro and in vivo. Genome-wide CRISPR-Cas9 screening also identified RASGRP1(Ras guanine nucleotide-releasing protein 1) and VPS28(Vacuolar protein sorting-associated protein 28) genes as synthetically lethal in response to TMZ treatment in the U87-KRAS cells. We found that RASGRP1 activated the RAS-mediated DDR pathway by promoting the RAS-GTP transformation. VPS28 promoted the Exos secretion and decreased intracellular TMZ concentration in GBM cells. The targeted Exos delivery system encapsulating drugs and siRNAs together showed a powerful therapeutic effect against GBM in vivo. Conclusions: We demonstrate a new mechanism by which ERBIN is epigenetically silenced by the RAS signaling in the MES subtype of GBM. Restoration of the ERBIN expression with EPIC-0412 significantly inhibits the RAS signaling downstream. RASGRP1 and VPS28 genes are associated with the promotion of TMZ resistance through RAS-GDP to RAS-GTP transformation and TMZ efflux, as well. A quadruple combination therapy based on a targeted Exos delivery system demonstrated significantly reduced tumor burden in vivo. Therefore, our study provides new insights and therapeutic approaches for regulating tumor progression and TMZ resistance in the MES-GBM subtype.

Mitochondrial Sirtuins in Cancer: A Revisited Review from Molecular Mechanisms to Therapeutic Strategies.

The sirtuin (SIRT) family is well-known as a group of deacetylase enzymes that rely on nicotinamide adenine dinucleotide (NAD+). Among them, mitochondrial SIRTs (SIRT3, SIRT4, and SIRT5) are deacetylases located in mitochondria that regulate the acetylation levels of several key proteins to maintain mitochondrial function and redox homeostasis. Mitochondrial SIRTs are reported to have the Janus role in tumorigenesis, either tumor suppressive or oncogenic functions. Although the multi-faceted roles of mitochondrial SIRTs with tumor-type specificity in tumorigenesis, their critical functions have aroused a rising interest in discovering some small-molecule compounds, including inhibitors and activators for cancer therapy. Herein, we describe the molecular structures of mitochondrial SIRTs, focusing on elucidating their regulatory mechanisms in carcinogenesis, and further discuss the recent advances in developing their targeted small-molecule compounds for cancer therapy. Together, these findings provide a comprehensive understanding of the crucial roles of mitochondrial SIRTs in cancer and potential new therapeutic strategies.

Erlotinib suppresses tumorigenesis in a mouse model of colitis-associated cancer.

Colitis-associated cancer (CAC) in inflammatory bowel diseases exhibits more aggressive behavior than sporadic colorectal cancer; however, the molecular mechanisms remain unclear. No definitive preventative agent against CAC is currently established in the clinical setting. We investigated the molecular mechanisms of CAC in the azoxymethane/dextran sulfate sodium (AOM/DSS) mouse model and assessed the antitumor efficacy of erlotinib, a small molecule inhibitor of the epidermal growth factor receptor (EGFR). Erlotinib premixed with AIN-93 G diet at 70 or 140 parts per million (ppm) inhibited tumor multiplicity significantly by 96%, with ∼60% of the treated mice exhibiting zero polyps at 12 weeks. Bulk RNA-sequencing revealed more than a thousand significant gene alterations in the colons of AOM/DSS-treated mice, with KEGG enrichment analysis highlighting 46 signaling pathways in CAC development. Erlotinib altered several signaling pathways and rescued 40 key genes dysregulated in CAC, including those involved in the Hippo and Wnt signaling. These findings suggest that the clinically-used antitumor agent erlotinib might be repurposed for suppression of CAC, and that further studies are warranted on the crosstalk between dysregulated Wnt and EGFR signaling in the corresponding patient population.

Yogurt Prevents Colorectal Tumorigenesis in ApcMin/+ Mice.

SCOPE: Yogurt consumption is related to a decreased risk of colorectal cancer (CRC), but whether such association is causal remains unclear. Patients with familial adenomatous polyposis (FAP) are at increased risk of CRC development. Here, the study investigates the efficacy of yogurt for intestinal polyposis chemoprevention in ApcMin/+ mice, a preclinical model for human FAP. METHODS AND RESULTS: A 10-week yogurt supplementation (15 g kg-1) in ApcMin/+ mice significantly reduces the intestinal polyp number (6.50 ± 0.97 versus 1.80 ± 0.49; p < 0.001) compared to controls. 16S rRNA gene-based microbiota analysis suggests that yogurt supplementation may greatly modulate the gut microbiome composition, especially in the relative abundance of Lactobacillus and Bifidobacterium. Importantly, the fecal concentration of d-lactate (d-Lac, 0.39 ± 0.04 µmol g-1 versus 8.14 ± 0.62 µmol g-1; p < 0.001) is boosted by yogurt, while oral administration with d-Lac (125 or 250 mg kg-1) reduces the polyp number by 71.43% or 77.14% (p < 0.001), respectively. The study also observes that d-Lac does not affect cell viability and anchorage-independence in CRC cells, but it greatly suppresses epidermal growth factor (EGF) or 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cell transformation in preneoplastic cells. Mechanistically, it demonstrates that d-Lac may attenuate epithelial cell transformation by targeting PI3K/AKT/ß-catenin axis. CONCLUSION: Yogurt protects against intestinal polyposis in ApcMin/+ mice, and d-Lac may partially account for the chemopreventive effects above.

Xanthohumol Promotes Skp2 Ubiquitination Leading to the Inhibition of Glycolysis and Tumorigenesis in Ovarian Cancer.

Ovarian cancer is a common, highly lethal tumor. Herein, we reported that S-phase kinase-associated protein 2 (Skp2) is essential for the growth and aerobic glycolysis of ovarian cancer cells. Skp2 was upregulated in ovarian cancer tissues and associated with poor clinical outcomes. Using a customized natural product library screening, we found that xanthohumol inhibited aerobic glycolysis and cell viability of ovarian cancer cells. Xanthohumol facilitated the interaction between E3 ligase Cdh1 and Skp2 and promoted the Ub-K48-linked polyubiquitination of Skp2 and degradation. Cdh1 depletion reversed xanthohumol-induced Skp2 downregulation, enhancing HK2 expression and glycolysis in ovarian cancer cells. Finally, a xenograft tumor model was employed to examine the antitumor efficacy of xanthohumol in vivo. Collectively, we discovered that xanthohumol promotes the binding between Skp2 and Cdh1 to suppress the Skp2/AKT/HK2 signal pathway and exhibits potential antitumor activity for ovarian cancer cells.

Withaferin A Inhibits Liver Cancer Tumorigenesis by Suppressing Aerobic Glycolysis through the p53/IDH1/HIF-1α Signaling Axis.

BACKGROUND: The energy supply of certain cancer cells depends on aerobic glycolysis rather than oxidative phosphorylation. Our previous studies have shown that withaferin A (WA), a lactone compound derived from Withania somnifera, suppresses skin carcinogenesis at least partially by stabilizing IDH1 and promoting oxidative phosphorylation. Here, we have extended our studies to evaluate the anti-tumor effect of WA in liver cancer. METHODS: Differential expression of glycolysis-related genes between liver cancer tissues and normal tissues and prognosis were verified using an online database. Glycolysis-related protein expression was detected using western blot after overexpression and knockdown of IDH1 and mitochondrial membrane potential assay based on JC-1, and mitochondrial complex I activity was also detected. The inhibitory effect of WA on the biological functions of HepG2 cells was detected along with cell viability using MTT assay, scratch assay, clone formation assay, glucose consumption and lactate production assay. Western blot and qRT-PCR were used to detect the expression of proteins and genes related to IDH1, p53 and HIF1α signaling pathways. RESULTS: We first identified that IDH1 expression was downregulated in human liver cancer cells compared to normal liver cells. Next, we found that treatment of HepG2 cells with WA resulted in significantly increased protein levels of IDH1, accompanied by decreased levels of several glycolytic enzymes. Furthermore, we found that WA stabilized IDH1 proteins by inhibiting the degradation by the proteasome. The tumor suppressor p53 was also upregulated by WA treatment, which played a critical role in the upregulation of IDH1 and downregulation of the glycolysis-related genes. Under hypoxic conditions, glycolysis-related genes were induced, which was suppressed by WA treatment, and IDH1 expression was still maintained at higher levels under hypoxia. CONCLUSION: Taken together, our results indicated that WA suppresses liver cancer tumorigenesis by p53-mediated IDH1 upregulation, which promotes mitochondrial respiration, thereby inhibiting the HIF-1α pathway and blocking aerobic glycolysis.

Pantoprazole suppresses carcinogenesis and growth of hepatocellular carcinoma by inhibiting glycolysis and Na+/H+ exchange.

Hepatocellular carcinoma (HCC) is one of the deadliest cancers. The prevention and therapy for this deadly disease remain a global medical challenge. In this study, we investigated the effect of pantoprazole (PPZ) on the carcinogenesis and growth of HCC. Both diethylnitrosamine (DEN) plus CCl4-induced and DEN plus high fat diet (HFD)-induced HCC models in mice were established. Cytokines and cell proliferation-associated gene in the liver tissues of mice and HCC cells were analyzed. Cellular glycolysis and Na+/H+ exchange activity were measured. The preventive administration of pantoprazole (PPZ) at a clinically relevant low dose markedly suppressed HCC carcinogenesis in both DEN plus CCl4-induced and HFD-induced murine HCC models, whereas the therapeutic administration of PPZ at the dose suppressed the growth of HCC. In the liver tissues of PPZ-treated mice, inflammatory cytokines, IL1, CXCL1, CXCL5, CXCL9, CXCL10, CCL2, CCL5, CCL6, CCL7, CCL20, and CCL22, were reduced. The administration of CXCL1, CXCL5, CCL2, or CCL20 all reversed PPZ-suppressed DEN plus CCL4-induced HCC carcinogenesis in mice. PPZ inhibited the expressions of CCNA2, CCNB2, CCNE2, CDC25C, CDCA5, CDK1, CDK2, TOP2A, TTK, AURKA, and BIRC5 in HCC cells. Further results showed that PPZ reduced the production of these inflammatory cytokines and the expression of these cell proliferation-associated genes through the inhibition of glycolysis and Na+/H+ exchange. In conclusion, PPZ suppresses the carcinogenesis and growth of HCC, which is related to inhibiting the production of inflammatory cytokines and the expression of cell proliferation-associated genes in the liver through the inhibition of glycolysis and Na+/H+ exchange.

Ageing microenvironment mediates lymphocyte carcinogenesis and lymphoma drug resistance: From mechanisms to clinical therapy (Review).

Cellular senescence has a complex role in lymphocyte carcinogenesis and drug resistance of lymphomas. Senescent lymphoma cells combine with immunocytes to create an ageing environment that can be reprogrammed with a senescence­associated secretory phenotype, which gradually promotes therapeutic resistance. Certain signalling pathways, such as the NF­κB, Wnt and PI3K/AKT/mTOR pathways, regulate the tumour ageing microenvironment and induce the proliferation and progression of lymphoma cells. Therefore, targeting senescence­related enzymes or their signal transduction pathways may overcome radiotherapy or chemotherapy resistance and enhance the efficacy of relapsed/refractory lymphoma treatments. Mechanisms underlying drug resistance in lymphomas are complex. The ageing microenvironment is a novel factor that contributes to drug resistance in lymphomas. In terms of clinical translation, some senolytics have been used in clinical trials on patients with relapsed or refractory lymphoma. Combining immunotherapy with epigenetic drugs may achieve better therapeutic effects; however, senescent cells exhibit considerable heterogeneity and lymphoma has several subtypes. Extensive research is necessary to achieve the practical application of senolytics in relapsed or refractory lymphomas. This review summarises the mechanisms of senescence­associated drug resistance in lymphoma, as well as emerging strategies using senolytics, to overcome therapeutic resistance in lymphoma.

PFKFB3 regulates breast cancer tumorigenesis and Fulvestrant sensitivity by affecting ERα stability.

Estrogen receptor alpha (ERα) is expressed in approximately 70% of breast cancer cases and determines the sensitivity and effectiveness of endocrine therapy. 6-phosphofructo-2-kinase/fructose-2, 6-biphosphatase3 (PFKFB3) is a glycolytic enzyme that is highly expressed in a great many human tumors, and recent studies have shown that it plays a significant role in improving drug sensitivity. However, the role of PFKFB3 in regulating ERα expression and the underlying mechanism remains unclear. Here, we find by using immunohistochemistry (IHC) that PFKFB3 is elevated in ER-positive breast cancer and high expression of PFKFB3 resulted in a worse prognosis. In vitro and in vivo experiments verify that PFKFB3 promotes ER-positive breast cancer cell proliferation. The overexpression of PFKFB3 promotes the estrogen-independent ER-positive breast cancer growth. In an estrogen-free condition, RNA-sequencing data from MCF7 cells treated with siPFKFB3 showed enrichment of the estrogen signaling pathway, and a luciferase assay demonstrated that knockdown of PFKFB3 inhibited the ERα transcriptional activity. Mechanistically, down-regulation of PFKFB3 promotes STUB1 binding to ERα, which accelerates ERα degradation by K48-based ubiquitin linkage. Finally, growth of ER-positive breast cancer cells in vivo was more potently inhibited by fulvestrant combined with the PFKFB3 inhibitor PFK158 than for each drug alone. In conclusion, these data suggest that PFKFB3 is identified as an adverse prognosis factor for ER-positive breast cancer and plays a previously unrecognized role in the regulation of ERα stability and activity. Our results further explores an effective approach to improve fulvestrant sensitivity through the early combination with a PFKFB3 inhibitor.

DFMO inhibition of neuroblastoma tumorigenesis.

BACKGROUND: Most high-risk neuroblastoma patients who relapse succumb to disease despite the existing therapy. We recently reported increased event-free and overall survival in neuroblastoma patients receiving difluoromethylornithine (DFMO) during maintenance therapy. The effect of DFMO on cellular processes associated with neuroblastoma tumorigenesis needs further elucidation. Previous studies have shown cytotoxicity with IC50 values >5-15 mM, these doses are physiologically unattainable in patients, prompting further mechanistic studies at therapeutic doses. METHODS: We characterized the effect of DFMO on cell viability, cell cycle, apoptosis, neurosphere formation, and protein expression in vitro using five established neuroblastoma cell lines (BE2C, CHLA-90, SHSY5Y, SMS-KCNR, and NGP) at clinically relevant doses of 0, 50, 100, 500, 1000, and 2500 µM. Limiting Dilution studies of tumor formation in murine models were performed. Statistical analysis was done using GraphPad and the level of significance set at p = 0.05. RESULTS: There was not a significant loss of cell viability or gain of apoptotic activity in the in vitro assays (p > 0.05). DFMO treatment initiated G1 to S phase cell cycle arrest. There was a dose-dependent decrease in frequency and size of neurospheres and a dose-dependent increase in beta-galactosidase activity in all cell lines. Tumor formation was decreased in xenografts both with DFMO-pretreated cells and in mice treated with DFMO. CONCLUSION: DFMO treatment is cytostatic at physiologically relevant doses and inhibits tumor initiation and progression in mice. This study suggests that DFMO, inhibits neuroblastoma by targeting cellular processes integral to neuroblastoma tumorigenesis at clinically relevant doses.

Synergistic action of Hedyotis diffusa Willd and Andrographis paniculata in Nasopharyngeal Carcinoma: Downregulating AKT1 and upregulating VEGFA to curb tumorigenesis.

OBJECTIVE: Nasopharyngeal carcinoma (NPC) remains a challenging cancer to treat. This study investigates the molecular mechanisms of Hedyotis diffusa Willd (HDW) combined with Andrographis paniculata (AP) in treating NPC. METHODS: Key compounds and target genes in HDW and AP were analyzed using network pharmacology. Protein-protein interaction (PPI) networks were constructed with STRING and visualized using Cytoscape. MCODE identified critical clusters, while DAVID facilitated GO and KEGG analyses. In vivo and in vitro experiments evaluated HDW-AP effects on NPC, including tumor volume, weight, Ki-67 expression, cell apoptosis, migration, invasion, cell cycle distribution, and DNA damage. RESULTS: The database identified 495 NPC-related genes and 26 compounds in the HDW-AP pair, targeting 165 genes. Fifty-eight potential therapeutic genes were found, leading to 18 key targets. KEGG analysis revealed a significant impact on 78 pathways, especially cancer pathways. Both in vivo and in vitro tests showed HDW-AP inhibited NPC cell proliferation, migration, invasion, and induced apoptosis. Mechanistically, this was achieved through AKT1 downregulation and VEGFA upregulation. CONCLUSION: The combination of HDW and AP targets 16 key genes to impede the development of NPC, primarily by modulating AKT1 and VEGFA pathways.

ß-Lapachone, an NQO1 bioactivatable drug, prevents lung tumorigenesis in mice.

Lung cancer is one of the most lethal cancers with high incidence worldwide. The prevention of lung cancer is of great significance to reducing the social harm caused by this disease. An in-depth understanding of the molecular changes underlying precancerous lesions is essential for the targeted chemoprevention against lung cancer. Here, we discovered an increased NQO1 level over time within pulmonary premalignant lesions in both the KrasG12D-driven and nicotine-derived nitrosamine ketone (NNK)-induced mouse models of lung cancer, as well as in KrasG12D-driven and NNK-induced malignant transformed human bronchial epithelial cells (BEAS-2B and 16HBE). This suggests a potential correlation between the NQO1 expression and lung carcinogenesis. Based on this finding, we utilized ß-Lapachone (ß-Lap), an NQO1 bioactivatable drug, to suppress lung tumorigenesis. In this study, the efficacy and safety of low-dose ß-Lap were demonstrated in preventing lung tumorigenesis in vivo. In conclusion, our study suggests that long-term consumption of low-dose ß-Lap could potentially be an effective therapeutic strategy for the prevention of lung premalignant lesions. However, further studies and clinical trials are necessary to validate our findings, determine the safety of long-term ß-Lap usage in humans, and promote the use of ß-Lap in high-risk populations.

Characterization of structural, genotoxic, and immunological effects of methyl methanesulfonate (MMS) induced DNA modifications: Implications for inflammation-driven carcinogenesis.

Genotoxic DNA damaging agents are the choice of chemicals for studying DNA repair pathways and the associated genome instability. One such preferred laboratory chemical is methyl methanesulfonate (MMS). MMS, an SN2-type alkylating agent known for its ability to alkylate adenine and guanine bases, causes strand breakage. Exploring the outcomes of MMS interaction with DNA and the associated cytotoxicity will pave the way to decipher how the cell confronts methylation-associated stress. This study focuses on an in-depth understanding of the structural instability, induced antigenicity on the DNA molecule, cross-reactive anti-DNA antibodies, and cytotoxic potential of MMS in peripheral lymphocytes and cancer cell lines. The findings are decisive in identifying the hazardous nature of MMS to alter the intricacies of DNA and morphology of the cell. Structural alterations were assessed through UV-Vis, fluorescence, liquid chromatography, and mass spectroscopy (LCMS). The thermal instability of DNA was analyzed using duplex melting temperature profiles. Scanning and transmission electron microscopy revealed gross topographical and morphological changes. MMS-modified DNA exhibited increased antigenicity in animal subjects. MMS was quite toxic for the cancer cell lines (HCT116, A549, and HeLa). This research will offer insights into the potential role of MMS in inflammatory carcinogenesis and its progression.

The 11th Conference on metal toxicity and carcinogenesis.

Metal exposure is linked to numerous pathological outcomes including cancer, cardiovascular disease, and diabetes. Over the past decades, we have made significant progress in our understanding of how metals are linked to disease, but there is still much to learn. In October 2022, experts studying the consequences of metal exposures met in Montréal, Québec, to discuss recent advances and knowledge gaps for future research. Here, we present a summary of presentations and discussions had at the meeting.