Protein phosphatase 6 promotes stemness of colorectal cancer cells.

Colorectal cancer (CRC) remains a significant global health concern, demanding a more profound comprehension of its molecular foundations for the development of improved therapeutic strategies. This study aimed to elucidate the role of protein phosphatase 6 (PP6), a member of the type 2A protein phosphatase family, in CRC. Protein phosphatase 6 functions as a heterotrimer with a catalytic subunit (PP6c), regulatory subunits (PP6Rs; PP6R1, PP6R2, and PP6R3), and scaffold subunits (ANKRD28, ANKRD44, and ANKRD52). Elevated PP6c expression has been identified in CRC tissues compared to normal mucosa, aligning with its potential involvement in CRC pathogenesis. PP6c knockdown resulted in decreased colony-forming ability and in vivo proliferation of various CRC cell lines. Transcriptome analysis revealed that PP6c knockdown resulted in altered expression of genes associated with cancer stemness. Notably, the PP6c-PP6R3 complex is a key player in regulating cancer stem cell (CSC) markers. Additionally, increased PP6c expression was observed in CSC-like cells induced by sphere formation, implicating the role of PP6c in CSC maintenance. This study highlights the role of PP6c in CRC and suggests that it is a potential therapeutic target disrupting a pathway critical for CRC progression and stem cell maintenance.

Patterns of recovery in extant and extirpated seabirds after the world's largest multipredator eradication.

Eradicating invasive predators from islands can result in substantial recovery of seabirds, but the mechanisms that drive population changes remain poorly understood. Meta-analyses have recently revealed that immigration is surprisingly important to the recovery of philopatric seabirds, but it is not known whether dispersal and philopatry interact predictably to determine rates of population growth and changes of distribution. We used whole-island surveys and long-term monitoring plots to study the abundance, distribution, and trends of 4 burrowing seabird species on Macquarie Island, Australia, to examine the legacy impacts of invasive species and ongoing responses to the world's largest eradication of multiple species of vertebrates. Wekas (Gallirallus australis) were eradicated in 1988; cats (Felis catus) in 2001; and rabbits (Oryctolagus cuniculus), black rats (Rattus rattus), and mice (Mus mus) in 2011-2014. We compared surveys from 1976-1979 and 2017-2018 and monitoring from the 1990s and 2000s onward. Antarctic prions (Pachyptila desolata) and white-headed petrels (Pterodroma lessonii) increased ∼1% per year. Blue petrels (Halobaena caerulea) and gray petrels (Procellaria cinerea) recolonized following extirpation from the main island in the 1900s but remained spatially and numerically rare in 2018. However, they increased rapidly at 14% and 10% per year, respectively, since cat eradication in 2001. Blue and gray petrel recolonization occurred on steep, dry, west-facing slopes close to ridgelines at low elevation (i.e., high-quality petrel habitat). They overlapped <5% with the distribution of Antarctic prion and white-headed petrels which occurred in suboptimal shallow, wet, east-facing slopes at high elevation. We inferred that the speed of population growth of recolonizing species was related to their numerically smaller starting size compared with the established species and was driven by immigration and selection of ideal habitat.

Patrones de recuperación en aves marinas existentes y extirpadas después de la mayor erradicación mundial de multidepredadores Resumen La erradicación de depredadores invasores en las islas puede derivar en la recuperación sustancial de aves marinas, aunque entendemos muy poco los mecanismos que causan los cambios poblacionales. Los metaanálisis recientes han revelado que la inmigración es de gran importancia para la recuperación de aves marinas filopátricas, aunque no sabemos si la dispersión y la filopatría interactúan de forma predecible para poder determinar las tasas de crecimiento poblacional y los cambios en la distribución. Aplicamos censos de isla completa y parcelas de monitoreo a largo plazo para estudiar la abundancia, distribución y tendencias de cuatro especies de aves marinas cavadoras en la Isla Macquarie, Australia, para analizar los impactos heredados de las especies invasoras y la respuesta continua a la mayor erradicación mundial de varias especies de vertebrados. El rascón weka (Gallirallus australis) se erradicó en 1988; los gatos (Felis catus) en 2001; y los conejos (Oryctolagus cuniculus), ratas (Rattus rattus) y ratones (Mus mus) entre 2011 y 2014. Comparamos los censos de 1976-1979 y 2017-2018 y el monitoreo realizado en los 90s y del año 2000 en adelante. El pato petrel antártico (Pachyptila desolata) y el petrel cabeciblanco (Pterodroma lessonii) incrementaron ∼1% por año. El petrel azulado (Halobaena caerulea) y la pardela gris (Procellaria cinerea) recolonizaron la isla después de su extirpación en la década de 1900, pero todavía eran especies raras espacial y numéricamente en 2018. Sin embargo, esta especie incrementó rápidamente en un 14% y 10% por año respectivamente desde que se erradicaron los gatos en 2001. La recolonización ocurrió desde las laderas empinadas, secas y con orientación al oeste en los sistemas montañosos de baja elevación (es decir, hábitats de gran calidad para los petreles). La distribución del petrel azulado y la pardela gris ocurrió en laderas someras subóptimas y húmedas con orientación al este a altas elevaciones. Esta distribución se traslapó menos del 5% con la del pato petrel antártico y la del petrel cabeciblanco. Inferimos que la velocidad del crecimiento poblacional de las especies que recolonizaron estuvo relacionada con el menor tamaño inicial en comparación con las especies establecidas y fue causada por la inmigración y la selección del hábitat ideal.

Interference of two typical polycyclic aromatic hydrocarbons on the induced anti-grazing defense of Tetradesmus obliquus.

Anthropogenic emissions of polycyclic aromatic hydrocarbons (PAHs) cause severe ecological impacts by contaminating natural water bodies, affecting various biological groups, and altering interspecies relationships and ecological functions. This study examined the effects of two typical PAHs, phenanthrene (Phe) and naphthalene (Nap), on the anti-grazing defense mechanisms of Tetradesmus obliquus, a primary producer in freshwater food chains. Four non-lethal concentrations (0.01, 0.1, 1, and 10 mg L-1) of Phe and Nap were tested and the population growth, photosynthetic capacity, pigment content, and morphological defense of T. obliquus were analyzed. The results indicated that Phe and Nap inhibited both the growth rate and formation of defensive colonies of T. obliquus induced by Daphnia grazing cues, and the inhibition ratio increased with concentration. Phe and Nap significantly shortened the defense colony formation time of T. obliquus. Phe and Nap significantly suppressed photosynthesis in the early stages; however, the photosynthetic efficiency recovered over time. These findings highlight the high sensitivity of grazing-induced colony formation in T. obliquus to Phe and Nap at non-lethal concentrations, which could affect the interactions between phytoplankton and zooplankton in aquatic ecosystems. Our study underscores the influence of Phe and Nap on the defense mechanisms of phytoplankton and the consequential effects on ecological interactions within freshwater ecosystems, providing insight into the complex impacts of pollutants on phytoplankton-zooplankton relationships. Therefore, it is necessary to consider interspecific interactions when assessing the potential negative effects of environmental pollutants on aquatic ecosystems.

Tretinoin (2,4-difluoro-phenyl) triazole activates proapoptotic protein expression and targets NRP2 protein to inhibit esophageal carcinoma cell growth.

The present study investigated the effect of tretinoin (2,4-difluoro-phenyl) triazole (TDFPT) on the growth and proliferation of Kyse-270 and EC9706 esophageal carcinoma cells and explored the underlying mechanism. The results demonstrated that TDFPT treatment of Kyse-270 and EC9706 cells led to a dose-dependent reduction in cell proliferation. Colony formation was significantly (p < .05) reduced in Kyse-270 and EC9706 cells on treatment with various concentrations of TDFPT. In TDFPT-treated Kyse-270 and EC9706 cells, the expression of Bcl-2 protein showed a remarkable decrease, whereas the level of Bax protein was found to be higher compared with the control cells. Cell invasion showed a prominent decrease in Kyse-270 and EC9706 cells on treatment with TDFPT. Treatment with TDFPT led to a prominent suppression in the expression of MMP-9 and NRP2 in Kyse-270 and EC9706 cells. In silico studies using the AutoDock Vina and discovery studio software revealed that various confirmations of TDFPT bind to NRP2 protein with the affinity ranging from -8.6 to -6.1 kcal/mol. It was found that the TDFPT interacts with NRP2 protein by binding to alanine (ALA A:295), proline (PRO A:306), glutamine (GLN A:307), and isoleucine (ILE A:293) amino acid residues. In summary, TDFPT exposure suppresses esophageal carcinoma cell proliferation, inhibits colony formation ability, and activates apoptotic pathway. Thus, TDFPT acts as an effective antiproliferative agent for esophageal carcinoma cells and needs to be investigated further as chemotherapeutic molecule.

LncRNA ADAMTS9-AS1 inhibits the stemness of lung adenocarcinoma cells by regulating miR-5009-3p/NPNT axis.

We sought to extend our observation of LncRNA ADAMTS9-AS1 and to specifically uncover its role on the stemness of lung adenocarcinoma (LUAD) cancer cells. ADAMTS9-AS1 was poorly expressed in LUAD. The high ADAMTS9-AS1 expression was positively associated with overall survival. ADAMTS9-AS1 overexpression attenuated the colony-forming capacity and reduced stem cell-like population of LUAD cancer stem cells (CSCs). Furthermore, ADAMTS9-AS1 overexpression increased E-cadherin expression in addition to the downregulated expressions of Fibronectin and Vimentin in LUAD spheres. In vitro results also confirmed the ADAMTS9-AS1's inhibitory effect on the growth of LUAD cells. Moreover, the antagonistic repression of miR-5009-3p levels with the expression of ADAMTS9-AS1 and NPNT was confirmed. Finally, ADAMTS9-AS1 overexpression curbed the increasing stemness of LUDA-CSC caused by NPNT silencing, thus leading to the suppression of LUAD progression in vitro. Conclusively, ADAMTS9-AS1 negatively controls the LUAD cancer cell stemness progression through regulating miR-5009-3p/NPNT axis.

SLITRK6 promotes the progression of lung adenocarcinoma by regulating PI3K/AKT/mTOR signaling and Warburg effect.

To investigate the role of SLITRK6 in lung adenocarcinoma (LUAD) and the underlying mechanism in it, clinical tissues and tissue microarray of LUAD were used to detect the expression of SLITRK6. In vitro cell viability assay and colony formation assay in LUAD cells were conducted to investigate SLITRK6 related biological functions. In vivo subcutaneous model was used to determine the role of SLITRK6 in LUAD growth. It was found that the expression of SLITRK6 was significantly upregulated in LUAD tissues compared with that in para-cancerous tissues. Knockdown of SLITRK6 suppressed the proliferation and colony formation of LUAD cells in vitro. Meanwhile, the growth of LUAD cells was also inhibited by SLITRK6 knockdown in vivo. Furthermore, we found that SLITRK6 knockdown could suppress the glycolysis of LUAD cells by regulating the phosphorylation of AKT and mTOR. All results suggest that SLITRK6 promotes LUAD cell proliferation and colony formation by regulating PI3K/AKT/mTOR signaling and Warburg effect. SLITRK6 may serve as a potential therapeutic target for LUAD in future.

Functional role and epithelial to mesenchymal transition of the miR-590-3p/MDM2 axis in hepatocellular carcinoma.

BACKGROUND: There is considerable evidence that microRNAs (miRNAs) regulate several key tumor-associated genes/pathways and may themselves have a dual regulatory function either as tumor suppressors or oncogenic miRNA, depending on the tumor type. MicroRNA-590-3p (miR-590-3p) is a small non-coding RNA involved in the initiation and progression of numerous tumors. However, its expression pattern and biological role in hepatocellular carcinoma (HCC) are controversial. RESULTS: In the current work, computational and RT-qPCR analysis revealed that HCC tissues and cell lines exhibited miR-590-3p downregulation. Forced expression of miR-590-3p attenuated HepG2 cells proliferation, migration, and repressed EMT-related gene expression. Bioinformatic, RT-qPCR, and luciferase assays revealed that MDM2 is a direct functional target of miR-590-3p. Moreover, the knockdown of MDM2 mimicked the inhibitory effect of miR-590-3p in HepG2 cells. CONCLUSION: We have identified not only novel targets for miR-590-3p in HCC, but also novel target genes for miR590-3p/MDM2 pathway in HCC like SNAIL, SLUG, ZEB1, ZEB2, and N-cadherin. Furthermore, these findings demonstrate a crucial role for MDM2 in the regulatory mechanism of EMT in HCC.

Pseurotin A Validation as a Metastatic Castration-Resistant Prostate Cancer Recurrence-Suppressing Lead via PCSK9-LDLR Axis Modulation.

Metastatic castration-resistant prostate cancer (mCRPC) cells can de novo biosynthesize their own cholesterol and overexpress proprotein convertase subtilisin/kexin type 9 (PCSK9). PCSK9 proved to contribute to mCRPC cell motility since PCSK9 knockdown (KD) in mCRPC CWR-R1ca cells led to notable reductions in cell migration and colony formation. Human tissue microarray results proved a higher immunohistoscore in patients ≥ 65 years old, and PCSK9 proved to be expressed higher at an early Gleason score of ≤7. The fermentation product pseurotin A (PS) suppressed PCSK9 expression, protein-protein interactions with LDLR, and breast and prostate cancer recurrences. PS suppressed migration and colony formation of the CWR-R1ca cells. The progression and metastasis of the CWR-R1ca-Luc cells subcutaneously (sc) xenografted into male nude mice fed a high-fat diet (HFD, 11% fat content) showed nearly 2-fold tumor volume, metastasis, serum cholesterol, low-density lipoprotein cholesterol (LDL-C), prostate-specific antigen (PSA), and PCSK9 levels versus mice fed a regular chow diet. Daily oral PS 10 mg/kg treatments prevented the locoregional and distant tumor recurrence of CWR-R1ca-Luc engrafted into nude mice after primary tumor surgical excision. PS-treated mice showed a significant reduction in serum cholesterol, LDL-C, PCSK9, and PSA levels. These results comprehensively validate PS as an mCRPC recurrence-suppressive lead by modulating the PCSK9-LDLR axis.

New Rare Triterpene Glycosides from Pacific Sun Star, Solaster pacificus, and Their Anticancer Activity.

Six previously unknown triterpene glycosides, pacificusosides L-Q (1-6), and two previously known triterpene glycosides, cucumariosides B1 (7) and A5 (8), were isolated from an alcoholic extract of Pacific sun star, Solaster pacificus. The structures of 1-6 were determined using 1D and 2D NMR, ESIMS, and chemical modifications. Compound 1 is a rare type of triterpene glycoside with non-holostane aglycon, having a linear trisaccharide carbohydrate chain. Pacificusosides M-P (2-5) have new structures containing a Δ8(9)-3,16,18-trihydroxy tetracyclic triterpene moiety. This tetracyclic fragment in sea star or sea cucumber triterpene glycosides was described for the first time. All the compounds under study exhibit low or moderate cytotoxic activity against colorectal carcinoma HCT 116 cells, and breast cancer MDA-MB-231 cells were assessed by MTS assay. Compound 2 effectively suppresses the colony formation of cancer cells at a non-toxic concentration, using the soft-agar assay. A scratch assay has shown a significant anti-invasive potential of compound 2 against HCT 116 cells, but not against MDA-MB-231 cells.

Grazing inhibition in Daphnia and Bosmina by colony formation of Desmodesmus subspicatus triggered by sodium octyl sulfate.

There are growing concerns that several aquatic contaminants can indirectly alter biological interactions by inhibiting the adaptive phenotypic plasticity of organisms, even at nonlethal concentrations. In Scenedesmaceae, a family of green algae, many chemicals interfere with defensive colony formation against grazers (i.e., through induced or limited coloniality). Although several studies have demonstrated that the effects of coloniality can limit the feeding capacity of Daphnia spp., grazing inhibition in other zooplankton species is not well understood. In this study, we examined the influence of sodium octyl sulfate (SOS) on the growth and morphology of Desmodesmus subspicatus and on the feeding rates of three cladoceran species (Daphnia galeata, Bosmina longirostris, and Bosmina fatalis) feeding on SOS-induced colonies under factorial conditions of different food levels and grazer ages. SOS remarkably induced colony formation with no observed effect on growth in D. subspicatus. D. galeata and B. fatalis showed a remarkable reduction in feeding rates when they fed on colonial D. subspicatus, whereas no significant effect of the prey morphotype was found on the feeding rates of B. longirostris. Microscopic observations of algal morphology after being grazed showed that each species can consume colonial prey depending on food level and age. Comparisons of the inhibition ratio of feeding among the three cladocerans revealed that Daphnia was more sensitive to prey coloniality compared with Bosmina. Our findings provide specific insights into the effects of chemically interfered colony formation on population dynamics and community structures.

Atractylenolide-1 affects glycolysis/gluconeogenesis by downregulating the expression of TPI1 and GPI to inhibit the proliferation and invasion of human triple-negative breast cancer cells.

Atractylenolide-1 (AT-1) is a major octanol alkaloid isolated from Atractylodes Rhizoma and is widely used to treat various diseases. However, few reports have addressed the anticancer potential of AT-1, and the underlying molecular mechanisms of its anticancer effects are unclear. This study aimed to assess the effect of AT-1 on triple-negative breast cancer (TNBC) cell proliferation and migration and explore its potential molecular mechanisms. Cell invasion assays confirmed that the number of migrating cells decreased after AT-1 treatment. Colony formation assays showed that AT-1 treatment impaired the ability of MDA-MB-231 cells to form colonies. AT-1 inhibited the expression of p-p38, p-ERK, and p-AKT in MDA-MB-231 cells, significantly downregulated the proliferation of anti-apoptosis-related proteins CDK1, CCND1, and Bcl2, and up-regulated pro-apoptotic proteins Bak, caspase 3, and caspase 9. The gas chromatography-mass spectroscopy results showed that AT-1 downregulated the metabolism-related genes TPI1 and GPI through the glycolysis/gluconeogenesis pathway and inhibited tumor growth in vivo. AT-1 affected glycolysis/gluconeogenesis by downregulating the expression of TPI1 and GPI, inhibiting the proliferation, migration, and invasion of (TNBC) MDA-MB-231 cells and suppressing tumor growth in vivo.

Anticancer Activity of Sunitinib Analogues in Human Pancreatic Cancer Cell Cultures under Normoxia and Hypoxia.

Pancreatic cancer remains one of the deadliest cancer types. It is usually characterized by high resistance to chemotherapy. However, cancer-targeted drugs, such as sunitinib, recently have shown beneficial effects in pancreatic in vitro and in vivo models. Therefore, we chose to study a series of sunitinib derivatives developed by us, that were proven to be promising compounds for cancer treatment. The aim of our research was to evaluate the anticancer activity of sunitinib derivatives in human pancreatic cancer cell lines MIA PaCa-2 and PANC-1 under normoxia and hypoxia. The effect on cell viability was determined by the MTT assay. The compound effect on cell colony formation and growth was established by clonogenic assay and the activity on cell migration was estimated using a 'wound healing' assay. Six out of 17 tested compounds at 1 µM after 72 h of incubation reduced cell viability by 90% and were more active than sunitinib. Compounds for more detailed experiments were chosen based on their activity and selectivity towards cancer cells compared to fibroblasts. The most promising compound EMAC4001 was 24 and 35 times more active than sunitinib against MIA PaCa-2 cells, and 36 to 47 times more active against the PANC-1 cell line in normoxia and hypoxia. It also inhibited MIA PaCa-2 and PANC-1 cell colony formation. Four tested compounds inhibited MIA PaCa-2 and PANC-1 cell migration under hypoxia, but none was more active than sunitinib. In conclusion, sunitinib derivatives possess anticancer activity in human pancreatic adenocarcinoma MIA PaCa-2 and PANC-1 cell lines, and they are promising for further research.

Laser Thermo-Photobiomodulation of Bone Marrow Mesenchymal Stem Cells.

We studied the effect of laser radiation of moderate intensity with a wavelength of 970 nm on the efficiency of colony formation of rat bone marrow mesenchymal stem cells (MSC) in vitro. In this case, photobimodulation and thermal heating of MSC occur simultaneously. This combined laser treatment allows increasing the number of colonies by 6 times in comparison with the control and by more than 3 times in comparison with thermal heating alone. The mechanism of such an increase is associated with combined thermal and light effects of laser radiation of moderate intensity, which stimulates cell proliferation. This phenomenon can be used as the basis for solving the most important task of cell transplantation, associated with the expansion of autologous stem cells and activation of their proliferative potential.

The α2,8-sialyltransferase 6 (St8sia6) localizes in the ER and enhances the anchorage-independent cell growth in cancer.

Sialylation, the final stage of post-translational modification of proteins, is achieved in the Golgi apparatus and is related to the malignant phenotype of cancer. Disialylation of ganglioside (GD3) by St8sia1 and polysialylation by St8sia2 and 4 have been shown to be related to malignant phenotypes; however, di/oligosialylation by St8sia6 is still unknown. In this study, we analyzed the malignant phenotype of St8sia6 and found that upregulation of St8sia6 in melanoma B16 cells increased anchorage-independent cell growth, which was not due to sialic acid cleavage by a sialidase. Moreover, unlike other sialyltransferases, St8sia6 localized to the endoplasmic reticulum (ER). We found that the localization to the Golgi apparatus could be regulated by swapping experiments using St8sia2; however, the malignant phenotype did not change. These data demonstrate that the enhancement of anchorage-independent cell growth by St8sia6 is not due to its localization of ER, but is due to the expression of the protein itself.

Extracellular Regucalcin Suppresses the Growth, Migration, Invasion, and Adhesion of Metastatic Human Prostate Cancer Cells.

INTRODUCTION: Regucalcin plays a multifunctional role in the regulation of cellular function including metabolism, signaling process, and transcriptional activity in maintaining cell homeostasis. Downregulated expression or activity of regucalcin contributes to the development of malignancies in various types of human cancer. Survival of cancer patients, including metastatic prostate cancer, is prolonged with high expression of regucalcin in the tumor tissues. METHODS: We elucidate whether extracellular regucalcin conquers the growth, migration, invasion, and adhesion of metastatic human prostate cancer PC-3 and DU-145 cells. RESULTS: Extracellular regucalcin (0.1, 1, and 10 nM) of physiologic levels (1 nM at human serum) inhibited colony formation and growth of PC-3 and DU-145 cells, while it did not have an effect on cell death. Repressive effects of extracellular regucalcin on the proliferation were not exhibited by the presence of inhibitors of the cell cycle, intracellular signaling process, and transcriptional activity, suggesting that the signals of extracellular regucalcin are transmitted to block cell growth. Furthermore, extracellular regucalcin (0.1, 1, or 10 nM) inhibited migration, invasion, and adhesion of PC-3 and DU-145 cells. Mechanistically, extracellular regucalcin (10 nM) decreased the levels of various signaling proteins including Ras, posphatidylinositol-3 kinase, mitogen-activated protein kinase, mechanistic target of rapamycin, RSK-2, caveolin-1, and integrin ß1 in PC-3 cells. DISCUSSION AND CONCLUSION: Thus, extracellular regucalcin may play a suppressive role in growth, migration, invasion, and adhesion, which are involved in the metastatic activity of human prostate cancer cells, via affecting diverse signaling processes. This study may provide a new strategy in preventing metastatic prostate cancer with exogenous regucalcin.

MiR-106b-5p regulates esophageal squamous cell carcinoma progression by binding to HPGD.

BACKGROUND: Several studies have documented the key role of microRNAs (miRNAs) in esophageal squamous cell carcinoma (ESCC). Although the expression of the 15-hydroxyprostaglandin dehydrogenase (HPGD) gene and miR-106b-5p are reportedly linked to cancer progression, their underlying mechanisms in ESCC remain unclear. METHODS: mRNA and miRNA expression in ESCC tissues and cells were analyzed using RT-qPCR. Luciferase and RNA pull-down assays were used to identify the interaction between miR-106b-5p and HPGD. Xenograft and pulmonary metastasis models were used to assess tumor growth and metastasis. CCK-8, BrdU, colony formation, adhesion, cell wound healing, Transwell, and caspase-3/7 activity assays, and flow cytometry and western blot analyses were used to examine the function of miR-106-5p and HPGD in ESCC cell lines. RESULTS: The findings revealed that miR-106b-5p expression was upregulated in ESCC tissues and cell lines. miR-106b-5p augmented cellular proliferation, colony formation, adhesion, migration, invasion, and proportion of cells in the S-phase, but reduced apoptosis and the proportion of cells in G1-phase. Silencing of miR-106-5p inhibited tumor growth in vivo and pulmonary metastasis. Although HPGD overexpression suppressed proliferation, colony formation, adhesion, migration, and invasion of ESCC cells, it promoted apoptosis and caused cell cycle arrest of the ESCC cells. The results also indicated a direct interaction of HPGD with miR-106b-5p in ESCC cells. Furthermore, miR-106b-5p inhibited HPGD expression, thereby suppressing ESCC tumorigenesis. CONCLUSION: Our data suggest that miR-106b-5p enhances proliferation, colony formation, adhesion, migration, and invasion, and induces the cycle progression, but represses apoptosis of ESCC cells by targeting HPGD. This suggests that the miR-106b-5p/HPGD axis may serve as a promising target for the diagnosis and treatment of ESCC.

PLOD1 acts as a tumor promoter in glioma via activation of the HSF1 signaling pathway.

Procollagen-lysine, 2-oxoglutarate 5-dioxygenase 1 (PLOD1) is a collagen-related lysyl hydroxylase and its prognostic value in glioma patients was verified. However, its biological function in glioma has yet to be fully investigated. The PLOD1 mRNA status and clinical significance in gliomas were assessed via the GEPIA database. Overexpression or targeted depletion of PLOD1 was carried out in the human glioma cell line U87 and verified by western blotting. CCK8 and colony formation assays were implemented to examine the impact of PLOD1 on the proliferative and colony-forming phenotypes of U87 cells. Luciferase reporter assays and HSF1-specific pharmacologic inhibitors (KRIBB11) were employed to determine the regulatory relationship between PLOD1 and heat shock factor 1 (HSF1). High expression of PLOD1 was observed in tissue samples of glioblastoma multiforme (GBM) and brain lower-grade glioma (LGG). GEPIA overall survival further demonstrated that both GBM and LGG patients with high PLOD1 displayed worse clinical outcomes compared with those with low PLOD1. Overexpression and targeted depletion of PLOD1 enhanced and suppressed U87 cell proliferation and colony formation, respectively. Luciferase reporter assays showed that PLOD1 significantly enhanced the transcriptional activity of HSF1 in HEK293T cells. PLOD1 deficiency in U87 cells inhibited HSF1-induced survivin accumulation, whereas KRIBB11 also blocked the PLOD1-overexpressing induced survivin expression. An inhibitor of HSF1 signaling events abolished the increased clonogenic potential caused by PLOD1 overexpression in U87 cells. High expression of PLOD1 can increase the proliferation and colony formation of U87 cells by activating the HSF1 signaling pathway. This study suggested PLOD1/HSF1 as an effective therapeutic target for gliomas.

Permissive role of Na+/H+ exchanger isoform 1 in migration and invasion of triple-negative basal-like breast cancer cells.

In breast cancer, it is the resulting metastasis that is the primary cause of fatality. pH regulatory proteins and the tumor microenvironment play an important role in metastasis of cancer cells and acid-extruding proteins are critical in this process. There are several types of breast cancer and triple-negative breast cancer tends to be more metastatic and invasive and is itself is composed of several types. MDA-MB-468 are a triple-negative breast cancer cell line and are classified as basal-like and basal tumors account for up to 15% of breast cancers. Here we examined the effect of removal of the acid-extruding protein, the Na+/H+ exchanger isoform one, from MDA-MB-468 cells. NHE1 was deleted from these cells using the CRISPR/Cas9 system. Western blotting and measurement of activity confirmed the absence of the protein. In wounding/cell migration experiments, deletion of NHE1 reduced the rate of cell migration in the presence of low- or high-serum concentrations. Anchorage-dependent colony formation was also greatly reduced by deletion of the NHE1 protein. Cell proliferation was not affected by knockout of NHE1. The results demonstrate that NHE1 has an important role in migration and invasion of basal-like triple-negative breast cancer cells.

Diphenyleneiodonium efficiently inhibits the characteristics of a cancer stem cell model derived from induced pluripotent stem cells.

Diphenyleneiodonium (DPI) has long been evaluated as an anticancer drug inhibiting NADPH oxidase, the IC50 in several cancer cell lines was reported 10 µM, which is too high for efficacy. In this study, we employed miPS-Huh7cmP cells, which we previously established as a cancer stem cell (CSC) model from induced pluripotent stem cells, to reevaluate the efficacy of DPI because CSCs are currently one of the main foci of therapeutic strategy to treat cancer, but generally considered resistant to chemotherapy. As a result, the conventional assay for the cell growth inhibition by DPI accounted for an IC50 at 712 nM that was not enough to define the effectiveness as an anticancer drug. Simultaneously, the wound-healing assay revealed an IC50 of approximately 500 nM. Comparatively, the IC50 values shown on sphere formation, colony formation, and tube formation assays were 5.52, 12, and 8.7 nM, respectively. However, these inhibitory effects were not observed by VAS2780, also a reputed NADPH oxidase inhibitor. It is noteworthy that these three assays are evaluating the characteristic of CSCs and are designed in the three-dimensional (3D) culture methods. We concluded that DPI could be a suitable candidate to target mitochondrial respiration in CSCs. We propose that the 3D culture assays are more efficient to screen anti-CSC drug candidates and better mimic tumor microenvironment when compared to the adherent monolayer of 2D culture system used for a conventional assay, such as cell growth inhibition and wound-healing assays.

METTL3 promotes non-small cell lung cancer (NSCLC) cell proliferation and colony formation in a m6A-YTHDF1 dependent way.

BACKGROUND: N6-methyladenosine (m6A) is the most common RNA modification, which plays a pivotal role in tumor development and progression. In this study, we assessed the role of m6A methyltransferase METTL3 in FRAS1-involved cell proliferation and colony formation of non-small cell lung cancer (NSCLC) cell lines. METHODS: Cell viability was analyzed by Cell Counting Kit (CCK-8) and colony formation. M6A RNA immunoprecipitation (IP), Ribosomal immunoprecipitation, RNA immunoprecipitation (RIP) were performed to verify the relationship between METTL3, FRAS1 and YTHDF1. Rescue experiments to confirm the regulatory mechanism of METTL3-FRAS1 promoted NSCLC cell proliferation through CDON by cooperating YTHDF1. RESULTS: We found that FRAS1 was correlated with poor prognosis in NSCLC patients, of which the transcript undergoes m6A modification regulated by METTL3. METTL3 silence reduced cell viability of NSCLC cells HCC827 and NCI-H1975, which could be restored by FRAS1 overexpression. The m6A modification of FRAS1 could be recognized by YTHDF1. FRAS1 silence or YTHDF1 silence could rescue the elevated NSCLC cell proliferation, colony formation, and tumor growth induced by METTL3 overexpression in vitro and in vivo. CONCLUSIONS: Our study reveals that METTL3-FRAS1 plays a crucial role in NSCLC cell proliferation, colony formation, and tumor growth through the regulation of CDON by cooperating YTHDF1.