Human Gastrointestinal Cancer Research Articles

Calcium ion delivery by microbubble-assisted sonoporation stimulates cell death in human gastrointestinal cancer cells

Ultrasound-mediated cell membrane permeabilization – sonoporation, enhances drug delivery directly to tumor sites while reducing systemic side effects. The potential of ultrasound to augment intracellular calcium uptake – a critical regulator of cell death and proliferation – offers innovative alternative to conventional chemotherapy. However, calcium therapeutic applications remain underexplored in sonoporation studies. This research provides a comprehensive analysis of calcium sonoporation (CaSP), which combines ultrasound treatment with calcium ions and SonoVue microbubbles, on gastrointestinal cancer cells LoVo and HPAF-II. Initially, optimal sonoporation parameters were determined: an acoustic wave of 1MHz frequency with a 50% duty cycle at intensity of 2W/cm2. Subsequently, various cellular bioeffects, such as viability, oxidative stress, metabolism, mitochondrial function, proliferation, and cell death, were assessed following CaSP treatment. CaSP significantly impaired cancer cell function by inducing oxidative and metabolic stress, evidenced by increased mitochondrial depolarization, decreased ATP levels, and elevated glucose uptake in a Ca2+ dose-dependent manner, leading to activation of the intrinsic apoptotic pathway. Cellular response to CaSP depended on the TP53 gene's mutational status: colon cancer cells were more susceptible to CaSP-induced apoptosis and G1 phase cell cycle arrest, whereas pancreatic cancer cells showed a higher necrotic response and G2 cell cycle arrest. These promising results encourage future research to optimize sonoporation parameters for clinical use, investigate synergistic effects with existing treatments, and assess long-term safety and efficacy in vivo. Our study highlights CaSP's clinical potential for improved safety and efficacy in cancer therapy, offering significant implications for the pharmaceutical and biomedical fields.

Illuminating new possibilities: Effects of copper oxide nanoparticles on gastrointestinal adenocarcinoma cells in hypoxic condition

Cancer remains a major global health concern, necessitating the development of novel therapeutic approaches. Hypoxia is a common characteristic of solid tumors that plays a critical role in tumor progression, making it a prime target for anticancer therapies. This study aimed to determine the effects of copper oxide nanoparticles (CuONPs) on human gastrointestinal cancer cells in hypoxic condition for the first time. Toxicity of CuONPs was evaluated on human colon and gastric adenocarcinoma cells and normal fibroblasts by alamarBlue assay. Real-time polymerase chain reaction (PCR) was performed to study the effects of CuONPs on genes involved in cell apoptosis. To elucidate the molecular mechanisms underlying the effects of CuONPs in hypoxic condition, molecular docking was conducted on HIF-1α. Results revealed dose- and cell-type-dependent toxic effects of CuONPs, as a more significant (p < 0.0001) decrease in viability of LoVo cells (23 %) was observed compared to MKN-45 and HDF cells. In addition, CuONPs significantly (p < 0.0001) reduced LoVo cell viability down to 30.2 % in hypoxic condition. Gene expression analysis revealed significant (p < 0.0001) overexpression of P53 and BAX but downregulation of BCL-2 and CCND1 after treatment with CuONPs. Molecular docking indicated the preferable binding of CuONPs to the HIF-1α PAS-B domain through interaction with 15 residues with −4.8 kcal/mol binding energy. Our findings open up new possibilities for modulating HIF-1 activity and inhibiting hypoxia-induced tumor progression.

Intestinal Epithelia and Myeloid Immune Cells Shape Colitis Severity and Colorectal Carcinogenesis via High-mobility Group Box Protein 1.

High-mobility group box protein 1 [HMGB1] is a ubiquitous nucleoprotein with immune-regulatory properties following cellular secretion or release in sterile and in infectious inflammation. Stool and serum HMGB1 levels correlate with colitis severity and colorectal cancer [CRC] progression, yet recent reports indicate that HMGB1 mainly operates as an intracellular determinant of enterocyte fate during colitis, and investigations into the roles of HMGB1 in CRC are lacking. Using mice with conditional HMGB1-knockout in enterocytes [Hmgb1ΔIEC] and myeloid cells [Hmgb1ΔLysM], respectively, we explored functions of HMGB1 in pathogenetically diverse contexts of colitis and colitis-associated CRC. HMGB1 is overexpressed in human inflammatory bowel disease and gastrointestinal cancers, and HMGB1 protein localises in enterocytes and stromal cells in colitis and CRC specimens from humans and rodents. As previously described, enterocyte HMGB1 deficiency aggravates severe chemical-induced intestinal injury, but not Citrobacter rodentium or T cell transfer colitis in mice. HMGB1-deficient enterocytes and organoids do not exhibit deviant apoptotic or autophagic activity, altered proliferative or migratory capacity, abnormal intestinal permeability, or aberrant DSS-induced organoid inflammation in vitro. Instead, we observed altered in vivo reprogramming of both intestinal epithelia and infiltrating myeloid cells in Hmgb1ΔIEC early during colitis, suggesting HMGB1-mediated paracrine injury signalling. Hmgb1ΔIEC had higher CRC burden than wild types in the Apc+/min model, whereas inflammatory CRC was attenuated in Hmgb1ΔLysM. Cellular and molecular phenotyping of Hmgb1ΔIEC and Hmgb1ΔLysM cancers indicates context-dependent transcriptional modulation of immune signalling and extracellular matrix remodelling via HMGB1. Enterocytes and myeloid cells context-dependently regulate host responses to severe colitis and maladaptive intestinal wound healing via HMGB1.

A Bifidobacterium animalis subsp. lactis strain that can suppress Helicobacter pylori: isolation, in vitro and in vivo validation.

The administration of probiotics is an effective approach for treatment of Helicobacter pylori, which is associated with human gastrointestinal diseases and cancers. To explore more effective probiotics for H. pylori infection elimination, bacteria from infant feces were screened in this study. We successfully isolated the Bifidobacterium animalis subsp. lactis strains and evaluated its efficacy to inhibit H. pylori growth in vitro and in vivo. The results showed that a B. animalis strain (named BB18) sustained a high survival rate after incubation in gastric juice. The rapid urease test suggested that B. animalis BB18 reduced pathogen loads in H. pylori-infected Mongolian gerbils. Alleviation of H. pylori infection-induced gastric mucosa damage and decreased levels inflammatory cytokines were observed after the B. animalis BB18 administration. These findings demonstrated that B. animalis BB18 can inhibit H. pylori infection both in vitro and in vivo, suggesting its potential application for the prevention and eradication therapy of H. pylori infection.

Oncogenic Fatty Acid Metabolism Rewires Energy Supply Chain in Gastric Carcinogenesis

Background & AimsGastric carcinogenesis develops within a sequential carcinogenic cascade from pre-cancerous metaplasia to dysplasia and adenocarcinoma, and oncogenic gene activation can drive the process. Metabolic reprogramming is considered a key mechanism for cancer cell growth and proliferation. However, it remains unclear how metabolic changes contribute to the progression of metaplasia to dysplasia. We have examined metabolic dynamics during gastric carcinogenesis using a novel mouse model that induces Kras activation in zymogen-secreting chief cells. MethodsWe generated a Gif-rtTA;TetO-Cre;KrasG12D (GCK) mouse model which continuously induces active Kras expression in chief cells following doxycycline treatment. Histological examination and imaging mass spectrometry were performed in the GCK mouse stomachs at 2 to 14 weeks after doxycycline treatment. Mouse and human gastric organoids were used for metabolic enzyme inhibitor treatment. The GCK mice were treated with a stearoyl-CoA desaturase (SCD) inhibitor to inhibit the fatty acid desaturation. Tissue microarrays were used to assess the SCD expression in human gastrointestinal cancers. ResultsThe GCK mice developed metaplasia and high-grade dysplasia within 4 months. Metabolic reprogramming from glycolysis to fatty acid metabolism occurred during metaplasia progression to dysplasia. Altered fatty acid desaturation through SCD produces a novel Eicosenoic acid, which fuels dysplastic cell hyperproliferation and survival. The SCD inhibitor killed both mouse and human dysplastic organoids and selectively targeted dysplastic cells in vivo. SCD was upregulated during carcinogenesis in human gastrointestinal cancers. ConclusionsActive Kras expression only in gastric chief cells drives the full spectrum of gastric carcinogenesis. Also, oncogenic metabolic rewiring is an essential adaptation for high energy demand in dysplastic cells.

Flammutoxin, a Degradation Product of Transepithelial Electrical Resistance-Decreasing Protein, Induces Reactive Oxygen Species and Apoptosis in HepG2 Cells.

Proteins from Flammulina filiformis were prepared by sodium chloride extraction and fractionated by ammonium sulfate precipitation with increasing saturation degrees to obtain the protein fractions Ffsp-30, Ffsp-50, Ffsp-70, Ffsp-90, and Ffp-90. Among these protein fractions, Ffsp-50 possessed the most significant cytotoxic effect against three human gastrointestinal cancer cell lines, viz. HT-29, SGC-7901, and HepG2. SDS-PAGE and MALDI-TOF/TOF MS/MS analyses revealed that flammutoxin (FTX) was present as a dominating protein in Ffsp-50, which was further evidenced by HPLC-MS/MS determination. Furthermore, native FTX was purified from Ffsp-50 with a molecular weight of 26.78 kDa, exhibiting notable cytotoxicity against gastrointestinal cancer cell lines. Both Ffsp-50 and FTX exposure could enhance intercellular reactive oxygen species (ROS) generation and induce significant apoptosis in HepG2 cells. FTX was identified to be relatively conserved in basidiomycetes according to phylogenetic analysis, and its expression was highly upregulated in the primordium as well as the pileus of the fruiting body from the elongation and maturation stages, as compared with that in mycelium. Taken together, FTX could remarkably inhibit cell growth and induce ROS and apoptosis in HepG2 cells, potentially participating in the growth and development of the fruiting body. These findings from our investigation provided insight into the antigastrointestinal cancer activity of FTX, which could serve as a biological source of health-promoting and biomedical applications.

MgO-ZnO nanoparticle as an efficient photocatalyst in the synthesis of substituted chromeno[4, 3-b]chromenes as effective drugs in gastrointestinal cancer therapy

Chromeno[4,3-b]chromenes are biologically active compounds that have many applications in medicine, especially, in gastrointestinal field because of their anti-inflammatory and antioxidant properties. In this study, an efficient and environmental benign photocatalyst MgO-ZnO is proposed for the synthesis of a range of substituted chromenes under irradiation of a common green laser. To characterize MgO-ZnO techniques such as FT-IR, DRS, XRD, and FE-SEM are employed to ascertain the structure and physicochemical properties of the nanomaterial. Furthermore, an in-vitro cellular toxicity test was achieved on HCT-116 human gastrointestinal cancer cell line by MTT assay.

ZnO-ZnS Heterostructure as a Potent Photocatalyst in the Preparation of Some Substituted Chromenes and Remarkable Antigastrointestinal Cancer Activity.

The nanosized hybrid material ZnO-ZnS was synthesized using the well-known sol-gel method, as a simple and environmentally friendly procedure. The material was then characterized using various techniques including FESEM, TEM, UV-vis, DRS, EDS, XRD, and FT-IR. The characterization studies revealed the generation of ZnO-ZnS nanoparticles with a mean size of around 25 nm. Moreover, DRS analysis provided a band gap of 3.05 eV for this nanomaterial. The photocatalytic properties of the ZnO-ZnS heterojunction was investigated in the synthesis of some substituted chromenes under mild reaction conditions. The results showed that the prepared nanophotocatalyst exhibits significantly higher activity compared to its individual components (ZnO and ZnS) and provides 73-87% yield with 0.01 g of ZnO-ZnS after 30 min. In addition, the nanophotocatalyst demonstrated a high reusability in the desired condensation reaction. The enhanced photocatalytic activity of ZnO-ZnS can be attributed to the slower recombination of the electron-hole pairs in this semiconductor material. The reactive species OH•, •O2-, and h+ are believed to play important roles in the photocatalytic system. Furthermore, cellular toxicity of ZnO-ZnS nanoparticles was evaluated on HCT-116 human gastrointestinal cancer cell line by MTT assay. The results proved a distinct reduction of cell viability, proofing cytotoxicity of nanoparticles on the cancer cells. This study highlights the potential of the nanoparticles against gastrointestinal cancer.

New Schiff bases derived from dimethylpyridine-1,2,4-triazole hybrid as cytotoxic agents targeting gastrointestinal cancers: Design, synthesis, biological evaluation and molecular docking studies

In this research, a series of novel hybrid structures of dimethylpyridine-1,2,4-triazole Schiff bases were designed, synthesized, and evaluated for their in vitro cytotoxic potency on several human gastrointestinal cancer cells (EPG, Caco-2, LoVo, LoVo/Dx, HT29) and normal colonic epithelial cells (CCD 841 CoN). Schiff base 4h was the most potent compound against gastric EPG cancer cells (CC50 = 12.10 ± 3.10 μM), being 9- and 21-fold more cytotoxic than 5-FU and cisplatin, respectively. Moreover, it was not toxic to normal cells. Regarding the cytotoxicity against colorectal cancer cells, compounds 4d and 4l exhibited good activity against HT29 cells (CC50 = 52.80 ± 2.80 μM and 61.40 ± 10.70 μM, respectively), and were comparable to or more potent than cisplatin and 5-FU. Also, they were less toxic to normal cells with a higher selectivity index (SI, CCD 841 CoN/HT29 = 4.20 and 2.85, respectively) than reference drugs (SI, CCD 841 CoN/HT29 < 1). Selected Schiff bases were subjected to the P-glycoprotein inhibition assay. Schiff bases 4d, 4e, and 4l influenced P-gp efflux function, significantly increasing the accumulation of rhodamine 123 in colon cancer cell lines. Further mechanistic studies showed that compound 4l induced apoptotic cell death through a caspase-dependent mechanism and by regulating the p53-MDM2 signaling pathway in HT29 cells. Also, physicochemical predictions of compounds 4d, 4e, 4h, and 4i were examined in silico. The results revealed that the compounds possessed promising drug-likeness profiles.

Iodine-Biofortified Lettuce Can Promote Mitochondrial Dependent Pathway of Apoptosis in Human Gastrointestinal Cancer Cells.

Previously, our research provided evidence that exposure of gastric and colon cancer cells to extracts from iodine-biofortified lettuce leads to a reduction of cell viability and proliferation through cell cycle arrest and upregulation of pro-apoptotic genes. The aim of the present study was to determine the potential cellular mechanisms of induction of cell death in human gastrointestinal cancer cell lines after treatment with iodine-biofortified lettuce. We demonstrated that extracts from lettuce enriched with iodine induce apoptosis in gastric AGS and colon HT-29 cancer cells and the mechanism of programmed cell death may be triggered and executed through different signaling pathways, depending on the type of cells. Western blot analysis revealed that iodine-fortified lettuce leads to cell death through the release of cytochrome c to the cytosolic fraction and activation of the primary drivers of apoptosis: caspase-3, caspase-7, and caspase-9. Furthermore, we have reported that apoptotic effects of lettuce extracts may be mediated by poly (ADP-ribose) polymerase (PARP) and activation of pro-apoptotic Bcl-2 family proteins such as Bad, Bax, and BID. We also observed mitochondrial dysfunction with the dissipation of the mitochondrial membrane potential in cells exposed to lettuce extracts. Taken together, these results indicate that the organic form of iodine such as 5-ISA and 3,5-diISA is an important factor in the activation of intrinsic mitochondrial apoptotic pathway in AGS and HT-29 cancer cells in a p53-independent manner.

Abstract 645: Impact of sex differences on cross-talk between the gut microbiome, CEACAMs, and TGF-β signaling in cancers

Abstract Background: Sex differences, microbiome alterations and obesity are prominent factors modulating gastrointestinal (GI) cancers, such as colorectal cancer (CRC) and hepatocellular carcinoma (HCC). However, there is a limited understanding of the interactions between intestinal epithelial and immune cells that participate in the regulation of the microbiome and the prevention or promotion of inflammation and the development of cancer. CEACAM proteins are immune and epithelial cell regulators, and some CEACAMs (CEACAM1, 3, 5, and 6) bind to pathogenic microbes. CEACAMs and mutations of the encoding genes are potential drivers of microbiome changes through altered regulation of host-immune response, through a mechanism that we hypothesize involves TGF-β signaling. We found that genetic alterations in CEACAM-encoding genes correlate with scores of TGF-β pathway activity in GI cancers in The Cancer Genome Atlas (TCGA). Furthermore, nearly 40% of human GI cancers have genetic alterations in components and regulators of the TGF-β pathway. We, therefore, investigated crosstalk between pathogen-binding CEACAM1, the gut microbiome, and the multifunctional intrinsically disordered protein βII-spectrin (SPTBN1), a Smad3 adaptor in driving CRC and liver cancers. Methods: The DNA from fecal samples collected from wild-type mice or TGF-β signaling-deficient mice Smad4+/-Sptbn1+/- were analyzed through shotgun metagenomics sequencing to identify changes in gut microbiota composition. We examined CEACAM expression, changes in the T cell populations, liver inflammation, and cancer in tissues from liver-specific βII-spectrin knockout (LSKO) mice fed a Western diet. Results: Mice heterozygous for the Sptbn1 gene (Sptbn1+/-) combined with heterozygosity of Smad4 (Smad4+/-Sptbn1+/-) spontaneously developed GI cancers, in the C57BL/6J genetic background. These mice exhibit an increased bacterial species associated with CRC in humans (C. septicum) and decreased commensal gut microbes associated with a healthy microbiome (B. vulgatus, P. distasonis). In addition, male Sptbn1+/- mice spontaneously developed HCC and showed reduced regulatory T (Treg) cells, whereas female mice did not, suggesting that βII-spectrin has a role in immune cell homeostasis that may affect tumor suppression. Single cell analyses revealed that Ceacam1 expression decreases in hepatocytes in mice fed a Western diet. CEACAM1 levels are restored to normal in tissues from liver-specific βII-spectrin knockout (LSKO) mice. Furthermore, we observed diet-induced changes in the T cell populations, liver inflammation, and cancer are also blocked in LSKO mice. Conclusion: Our study highlights how two critical pathways, TGF-β signaling and immune mediators CEACAM1 and 5, can drive inflammation and cancer through microbiome alterations with host sex having marked impact on the relevant signaling pathways. Citation Format: Krishanu Bhowmick, Addison Klebanov, Sahara John, Xiaochun Yang, Xiyan Xiang, Anil Vegesna, Kazufumi Ohshiro, James M. Crawford, Nicole Beauchemin, Raja Mazumder, Keith A. Crandall, Lopa Mishra. Impact of sex differences on cross-talk between the gut microbiome, CEACAMs, and TGF-β signaling in cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 645.

Benchmark for establishment of organoids from gastrointestinal epithelium and cancer based on available consumables and reagents.

Gastrointestinal cancers are a public health problem that threatens the lives of human being. A good experimental model is a powerful tool to promote the uncovering pathogenesis and establish novel treatment methods. High-quality biomedical research requires experimental models to recapitulate the physiological and pathological states of their parental tissues as much as possible. Organoids are such experimental models. Organoids refer to small organ-like cellular clusters formed by the expansion and passaging of living tissues in 3D culture medium in vitro. Organoids are highly similar to the original tissues in terms of cellular composition, cell functions, and genomic profiling. Organoids have many advantages, such as short preparation cycles, long-term storage based on cryopreservation, and reusability. In recent years, researchers carried out the establishment of organoids from gastrointestinal mucosa and cancer tissues, and accumulated valuable experiences. In order to promote effective usage and further development of organoid-related technologies in the research of gastrointestinal diseases, this study proposes a benchmark based on utilization of available experimental consumables and reagents, which are involved in the key steps such as collection and pretreatment of biospecimen, organoid construction, organoid cryopreservation and recovery, growth status evaluation, and organoid quality control. We believe that the standard for the construction and preservation of organoids derived from human gastrointestinal epithelium and cancer tissues can provide an important reference for the majority of scientific researchers.

Abstract C017: Unravelling tumor-intrinsic resistance mechanisms in pancreatic cancers to T-cell mediated cytotoxicity

Abstract The vast majority of human Gastrointestinal Cancers (GI) including colon, rectal and pancreatic cancers are resistant to immune checkpoint inhibitors (ICB), an immunotherapy strategy approved for the treatment of melanoma, non-small cell lung cancer, renal cancer and others. Although the lack of response has been largely attributed to their low tumor mutational burden, recent articles have demonstrated that neoantigen-specific tumor-infiltrating lymphocyte (TIL) can be successfully isolated in pancreatic cancer. This suggests that other factors, both tumor intrinsic and suppressive tumor microenvironmental, likely contribute to the lack of response of ICB. In this study we investigated the interplay between T cells and pancreatic tumors in vitro. To this aim we co-cultured a patient-derived pancreatic cell line, TC-4177, with autologous PBLs capable of recognizing the MMP14p.R158C neoantigen expressed by these cancer cells. Strikingly and in contrast to melanoma, this cancer cell line was not effectively recognized nor killed. The same results were obtained when co-culturing TC-4177 with MMPP14p.R158C specific TCR-transduced CD8+ T cells, suggesting that the lack of recognition was not due to T cell dysfunction but, rather, tumor intrinsic. The TC-4177 tumor cell line expressed the neoantigen at RNA level, did not present mutations in antigen presentation machinery, in the IFNg pathway nor in Caspase 8, suggesting none of the widely described resistance mechanisms to immune cell attack were limiting factors underpinning the poor recognition of this cell line. Furthermore, tumor cell recognition was restored upon exogenous neoantigen overexpression. Altogether, these results suggest that additional tumor-intrinsic mechanisms in pancreatic cancer cell line 4177 dampen T cell-mediated recognition and lysis that could be shared with other pancreatic tumors. To unravel the unknown resistance mechanism, a Genome-wide CRIPSR/Cas9 coculture-based screen was performed using this cell line. As a result, a number of genes known to be essential for T cell-mediated tumor immunity were identified, including key genes in the antigen presentation, IFN-g and TNF-a pathways. Further illustrating the robustness of the screen, sgRNAs targeting the antigen itself (MMP14) and the MMP14 HLA-restriction (HLA-B) conferred resistance to T cell killing. Moreover, in this screen we identified genes involved in known pathways that render susceptibility to T cell killing in pancreatic cancers such as autophagy pathway and vesicle trafficking. In addition to these pathways, genes involved in ubiquitination, chromatin remodeling and maintenance of gastrointestinal epithelium appeared to sensitize pancreatic cells to immune cell attack. Further experiments need to be performed to independently validate these candidates in the TC-4177 cell line as well as other pancreatic cell lines. Overall, these results open a new avenue to render pancreatic cancers susceptible to T cell killing and thus respond to immunotherapy. Citation Format: Judit Diaz, Pierre Levy, Jonatan Gonzalez, Asis Palazon, Sonia Guedan, Alena Gros. Unravelling tumor-intrinsic resistance mechanisms in pancreatic cancers to T-cell mediated cytotoxicity [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr C017.

Molecular Effects of Iodine-Biofortified Lettuce in Human Gastrointestinal Cancer Cells.

Considering the growing number of cancer cases around the world, natural products from the diet that exhibit potential antitumor properties are of interest. Our previous research demonstrated that fortification with iodine compounds is an effective way to improve the antioxidant potential of lettuce. The purpose of the present study was to evaluate the effect of iodine-biofortified lettuce on antitumor properties in human gastrointestinal cancer cell lines, gastric AGS and colon HT-29. Our results showed that extracts from iodine-biofortified lettuce reduce the viability and proliferation of gastric and colon cancer cells. The extracts mediated cell cycle arrest which was accompanied by inactivation of anti-apoptotic Bcl-2 and activation of caspases, as assessed by flow cytometry. However, extracts from lettuce fortified with organic forms of iodine acted more effectively than extracts from control and KIO3-enriched plants. Using quantitative PCR, we detected the increase in pro-apoptotic genes BAD, BAX and BID in AGS cells whereas up-regulation of cell cycle progression inhibitor CDKN2A and downregulation of pro-proliferative MDM2 in HT-29 cells. Interestingly, lettuce extracts led to down-regulation of pro-survival AKT1 and protooncogenic MDM2, which was consistent for extracts of lettuce fortified with organic form of iodine, 5-ISA, in both cell lines. MDM2 downregulation in HT-29 colon cancer cells was associated with RB1 upregulation upon 5-ISA-fortified lettuce extracts, which provides a link to the epigenetic regulation of tumor suppressor genes by RB/MDM2 pathway. Indeed, SEMA3A tumor suppressor gene was hypomethylated and upregulated in HT-29 cells treated with 5-ISA-fortified lettuce. Control lettuce exerted similar effects on RB/MDM2 pathway and SEMA3A epigenetic activation in HT-29 cells. Our findings suggest that lettuce as well as lettuce fortified with organic form of iodine, 5-ISA, may exert epigenetic anti-cancer effects that can be cancer type-specific.

FAM96A and FAM96B function as new tumor suppressor genes in breast cancer through regulation of the Wnt/β-catenin signaling pathway

AimsFamily with sequence similarity 96 member A and B (FAM96A and FAM96B) are two highly conserved homologous proteins belonging to MIP18 family. Some studies have shown that FAM96A and FAM96B are significantly down-regulated in human gastrointestinal stromal tumors, colon cancer, and liver cancer. However, the molecular mechanisms of FAM96A/B in breast cancer are unknown. This work aims to explore the roles of FAM96A/B in breast cancer progression. Main methodsSpecific siRNAs were used to down-regulate FAM96A/B expression, and recombinant plasmids were used to up-regulate FAM96A/B expression in breast cancer cells. Cell proliferation was measured using MTT and colony formation. Cell cycle and apoptosis were detected by flow cytometry. Cell migration and invasion were examined by wound healing and transwell assays. The relationships among FAM96A/B, EMT and Wnt/β-catenin pathway were determined by analyzing expression changes of classical markers. Key findingsWe found that FAM96A/B expression was down-regulated in breast cancer. FAM96A/B overexpression suppressed breast cancer cell proliferation, invasion and migration, induced cell apoptosis and caused cell cycle arrest. Conversely, FAM96A/B knockdown exhibited the opposite effects. Moreover, our data demonstrated that FAM96A/B overexpression suppressed EMT and Wnt/β-catenin pathway, while FAM96A/B knockdown showed the promoting effects on EMT and Wnt/β-catenin pathway. Furthermore, a Wnt pathway inhibitor, XAV-939 reversed the promoting effects of FAM96A/B knockdown on breast cancer progression. SignificanceOur findings suggest that FAM96A/B may function as new tumor suppressor genes and inhibit breast cancer progression via modulating Wnt/β-catenin pathway, which can provide the potential markers for breast cancer diagnosis and therapy.

Stability and Antiproliferative Activity of Malvidin-Based Non-Oxonium Derivative (Oxovitisin A) Compared with Precursor Anthocyanins and Pyranoanthocyanins

Oxovitisins are a unique group of anthocyanin derivatives with a non-oxonium nature and α-pyranone (lactone) D ring on the structure. In this study, oxovitisin A was synthesized through the micro-oxidative reaction of carboxypyranomalvidin-3-O-glucoside (vitisin A) with water, and its thermostability, pH, and SO2 color stability were studied compared with its two precursors, malvidin-3-O-glucoside (Mv3glc) and vitisin A, as well as methylpyrano-malvidin-3-O-glucoside (Me-py). Results showed that oxovitisin A exhibited the highest stabilities, which were inseparably related to its noncharged structure and the additional carbonyl group on the D ring. Moreover, the antiproliferative capacity of oxovitisin A was comparatively evaluated against two human gastrointestinal cancer cell lines. Interestingly, oxovitisin A presented the strongest antiproliferative ability on MKN-28 (IC50 = 538.42 ± 50.06 μM) and Caco-2 cells (IC50 = 434.85 ± 11.87 μM) compared with two other pyranoanthocyanins. Therefore, we conclude that oxovitisin A as a highly stable anthocyanin derivative still exhibits a satisfactory antiproliferative ability.

Gastrointestinal cancer-associated fibroblasts expressing Junctional Adhesion Molecule-A are amenable to infection by oncolytic reovirus

Gastrointestinal (GI) cancers are characterized by extensive tumor stroma that both promotes tumor progression and acts as a physical barrier for adjacent tumor cells, limiting the effect of current treatment modalities. Oncolytic virotherapy is currently investigated in clinical trials as a novel therapeutic agent for different malignancies of the GI tract, but it is largely unknown whether these viruses can also target the tumor stroma. Here, we investigated the tropism of two commonly studied OVs, adenovirus and reovirus, towards primary GI fibroblasts from human oesophageal, gastric, duodenal and pancreatic carcinomas (N = 36). GI fibroblasts were susceptible to type 3 Dearing (T3D) strain R124 and bioselected mutant reovirus (jin-3) infection but not oncolytic adenovirus (Ad5-Δ24). Efficient infection and apoptosis of human and mouse GI cancer-derived fibroblasts by these reoviruses was partially dependent on the expression of the reovirus entry receptor, Junctional Adhesion Molecule-A (JAM-A). Moreover, human GI cancer organoid-fibroblast co-cultures showed higher overall infectivity when containing JAM-A expressing fibroblasts as compared to JAM-A negative fibroblasts, indicating a potential role of JAM-A expressing fibroblasts for viral dissemination. We further show that JAM-A is not only necessary for efficient reovirus infection of fibroblasts but also partially mediates reovirus-induced apoptosis, dependent on signaling through the C-terminal PDZ-domain of JAM-A. Altogether, our data show the presence of JAM-A expressing fibroblasts in both human and murine GI cancers that are amenable to infection and induction of apoptosis by reovirus, extending the potential anti-cancer actions of reovirus with stromal targeting.

Design, synthesis, and cytotoxic activities of isaindigotone derivatives as potential anti-gastric cancer agents

A series of novel derivatives of isaindigotone, which comes from the root of isaits indinatca Fort, were synthesised (Compound 1–26). Four human gastrointestinal cancer cells (HCT116, PANC-1, SMMC-7721, and AGS) were employed to evaluate the anti-proliferative activity. Among them, Compound 6 displayed the most effective inhibitory activity on AGS cells with an IC50 (50% inhibitory concentration) value of 2.2 μM. The potential mechanism study suggested that Compound 6 induced apoptosis in AGS cells. The collapse of mitochondrial membrane potential (MMP) in AGS cells was proved. In docking analysis, good affinity interaction between Compound 6 and AKT1 was discovered. Treatment of AGS cells with Compound 6 also resulted in significant suppression of PI3K/AKT/mTOR signal pathway. The collapse of MMP and suppression of PI3K/AKT/mTOR signal pathway may be responsible for induction of apoptosis. This derivative Compound 6 could be useful as an underlying anti-tumour agent for treatment of gastric cancer.

Non-bacteria microbiome (virus, fungi, and archaea) in gastrointestinal cancer.

The gastrointestinal tract houses millions of microbes collectively referred to as the gut microbiome. The gut microbes comprise of bacteria, viruses, fungi, archaea, and microscopic eukaryotes, which co-evolved or colonize the gut forming complex symbiotic and mutualistic relationships. A state of homeostasis is required between host and gut microbiome relationship to maintain several host beneficial processes. Alterations in the taxonomic and functional composition of the gut microbes are associated with several human diseases including gastrointestinal cancers. Owed to their overwhelming abundance and ease of characterization, several studies focus on the role of bacteria in gastrointestinal cancers. There is however growing evidence that non-bacteria gut microbes are associated with the pathogenesis of gastrointestinal cancers. This review details the association of non-bacteria gut microbes including fungi, viruses, and archaea and their potential manipulation in the prevention and treatment of human gastrointestinal cancers.

Superoxide dismutase and the sigma1 receptor as key elements of the antioxidant system in human gastrointestinal tract cancers.

This long-term research was designed to evaluate whether superoxide dismutase (SOD) isoenzymes participate in the development of human gastrointestinal neoplasms and the potential influence of the sigma1 receptor (Sig1R) on the regulation of SOD gene expression during the neoplastic process. The experiments included human tissues from selected gastrointestinal tract tumors (liver cancer, colorectal adenocarcinoma, and colorectal cancer liver metastases). Activity, protein levels, and mRNA levels were determined for SOD isoenzymes and Sig1R. Additionally, markers of oxidative stress (glutathione, lipid peroxidation) were measured. The results showed significant changes in the antioxidant system activity in all examined types of tumors. SOD changed both in healthy cells and in neoplastic cells. The activity and expression of all studied enzymes significantly changed due to the advancement of tumor development. The Sig1R might be an additional regulator of the antioxidant system on which activity might depend on the survival and proliferation of cancer cells. Overall, the study shows that SOD1 and SOD2 are involved not only in the formation of neoplastic changes in the human gastrointestinal tissues (healthy intestine – colon tumor; healthy liver – liver cirrhosis – liver cancer) but also in the development of tumors in the sequence: benign tumor – malignant tumor – metastasis.