Induce Tumor Cell Differentiation Research Articles

Application of Biosurfactants in Medical Sciences.

Biosurfactants derived from microorganisms have attracted widespread attention in scientific research due to their unique surface activity, low toxicity, biodegradability, antibacterial properties, and stability under extreme conditions. Biosurfactants are widely used in many fields, such as medicine, agriculture, and environmental protection. Therefore, this review aims to comprehensively review and analyze the various applications of biosurfactants in the medical field. The central roles of biosurfactants in crucial medical areas are explored, like drug delivery, induction of tumor cell differentiation or death, treating bacterial and viral effects, healing wounds, and immune regulation. Moreover, a new outlook is introduced on optimizing the capabilities of biosurfactants through modification and gene recombination for better use in medicine. The current research challenges and future research directions are described, aiming to provide valuable insights for continuous study of biosurfactants in medicine.

Abstract PS16-04: Denosumab as an enhancer of the immune infiltrate in hormone receptor-positive early breast cancer. Subgroup analysis from the D-Biomark window-of-opportunity clinical trial (NCT03691311)

Abstract Background: The receptor activator of nuclear factor κB (RANK) signaling pathway has emerged as a therapeutic target in breast cancer (BC). Recent studies indicate that inhibition of the RANK pathway induces tumor cell differentiation and may enhance the anti-tumor immune response. The D-Biomark clinical trial aims to evaluate the antitumor (antiproliferative and proapoptotic) and immunomodulatory effects of denosumab in HER2-negative early BC. Methods: Patients with early HER2-negative BC scheduled for primary surgery were randomized in a 2:1 ratio to receive two doses of 120 mg denosumab on days 1 and 8 vs no treatment before surgery. Immunohistochemistry (IHC) was used to assess Ki67 (proliferation), cleaved caspase-3 (cell survival), RANK and RANKL. Stromal tumor infiltrating lymphocytes (TILs) and serum markers including free RANKL (sRANKL), tartrate-resistant acid phosphatase 5b (TRACP5b), and osteoprotegerin (OPG) were also analyzed. Paired t-test was used to compare values between core biopsy (biopsy A) and surgical samples (biopsy B). Subgroup analysis by intrinsic subtype was performed on 47 matched cases using PAM50. Results: Between July 2019 and May 2021, we enrolled 60 patients, 58 evaluable, including 10 triple-negative breast cancer (TNBC). The clinicopathologic characteristics of the population at the time of enrollment were well balanced, but the TNBC recruited included 5 out of 10 tumors with a more indolent behavior than the typical tumors of this lineage (apocrine tumors, low cell proliferation). Due to this and the small number of cases, no conclusions can be drawn in this subgroup. RANK expression was detected in 19 tumor cases, while 17 cases expressed RANKL. The treated group showed a decrease in sRANKL (p < 0.000), indicating denosumab activity, while the control group showed no change (p1.0). OPG levels in the experimental group showed a non-significant increase (p0.07), while TRACP5b remained unchanged. Both groups showed a non-clinically relevant increase in cell proliferation (5 percentage points), control p0.04, experimental p0.01. Subgroup analysis of tumors with RANK+ or RANKL+ tumor cells also showed no reduction in Ki67. Cell survival did not decrease in the overall cohort (control p0.05, experimental p0.24), nor in subgroups or in tumors with RANK+ or RANKL+ tumor cells. Denosumab treatment increased TILs in the overall population (control p0.06, experimental p0.0006) and in the subgroups: RANK+ tumors, RANKL+ tumors, premenopausal and postmenopausal, less so in the TNBC group. The subgroup analysis is shown in Table 1. Analysis by intrinsic subtype showed that in the experimental group there was an increase in cases with a change to luminal A lineage (17%) compared to the control group (6%), suggesting a possible cellular differentiation towards less aggressive tumors. Although the number of patients is small, these changes warrant further investigation and highlight the role of denosumab as an immune activator in these luminal tumors known for their low inflammatory infiltrate. Conclusion: Two doses of denosumab prior to surgery did not reduce proliferation or increase apoptosis. However, this short course of denosumab increased TILs in early BC, particularly in luminal tumors, and may induce tumor cell differentiation into luminal A-like tumors. Table. Citation Format: Andrea Vethencourt, Eva Trinidad, Eduard Dorca, Anna Petit, Teresa Soler-Monsó, Agostina Stradella, Cristina Capo, Ander Urriticoechea, Marta Matas, Gema Pérez-Chacon, María Jimenez, Marina Ciscar, Emilia Brizzi, Gonzalo Soria Alcaide, Gonzalo Gomez, Elena Piñeiro, Elvira Purqueras, Amparo Garcia, Ariadna Iserte, M Jesus Pla, Miriam Campos, Miguel Gil-Gil, Sonia Pernas, Eva Gonzalez-Suarez, Catalina Falo. Denosumab as an enhancer of the immune infiltrate in hormone receptor-positive early breast cancer. Subgroup analysis from the D-Biomark window-of-opportunity clinical trial (NCT03691311) [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PS16-04.

The TGF-β Family in Glioblastoma.

Members of the transforming growth factor β (TGF-β) family have been implicated in the biology of several cancers. In this review, we focus on the role of TGFβ and bone morphogenetic protein (BMP) signaling in glioblastoma. Glioblastoma (GBM) is the most common malignant brain tumor in adults; it presents at a median age of 64 years, but can occur at any age, including childhood. Unfortunately, there is no cure, and even patients undergoing current treatments (surgical resection, radiotherapy, and chemotherapy) have a median survival of 15 months. There is a great need to identify new therapeutic targets to improve the treatment of GBM patients. TGF-βs signaling promotes tumorigenesis in glioblastoma, while BMPs suppress tumorigenic potential by inducing tumor cell differentiation. In this review, we discuss the actions of TGF-βs and BMPs on cancer cells as well as in the tumor microenvironment, and their use in potential therapeutic intervention.

Estimation Of Alkaline Phosphatase In Oral Squamous Cell Carcinoma Patient

Oral squamous cell carcinoma (OSCC) is one of the life threatening and mutilating disease affecting the mankind. Most invasive OSCC are preceded by clinical premalignant lesions and conditions such as oral leukoplakia, erythroplakia, oral lichen planus, and oral submucous fibrosis (OSMF). These remain in preinvasive stage for years and the cancerous alterations remain indolent and not readily recognizable on clinical and histopathologic examination. There are various biological markers which can be used to monitor progression of precancerous lesions to cancer, predict the therapeutic response and prognostic outcome of cancer. Among these serum alkaline phosphates (ALP) is recognized as an important marker of induction of tumor cell differentiation. We attempt to analyze the role of these enzymes as a biomarker in OSCC cases.

Research Progress of Natural Small-Molecule Compounds Related to Tumor Differentiation.

Tumor differentiation is a therapeutic strategy aimed at reactivating the endogenous differentiation program of cancer cells and inducing cancer cells to mature and differentiate into other types of cells. It has been found that a variety of natural small-molecule drugs can induce tumor cell differentiation both in vitro and in vivo. Relevant molecules involved in the differentiation process may be potential therapeutic targets for tumor cells. Compared with synthetic drugs, natural small-molecule antitumor compounds have the characteristics of wide sources, structural diversity and low toxicity. In addition, natural drugs with structural modification and transformation have relatively concentrated targets and enhanced efficacy. Therefore, using natural small-molecule compounds to induce malignant cell differentiation represents a more targeted and potential low-toxicity means of tumor treatment. In this review, we focus on natural small-molecule compounds that induce differentiation of myeloid leukemia cells, osteoblasts and other malignant cells into functional cells by regulating signaling pathways and the expression of specific genes. We provide a reference for the subsequent development of natural small molecules for antitumor applications and promote the development of differentiation therapy.

Reciprocal impacts of telomerase activity and ADRN/MES differentiation state in neuroblastoma tumor biology

Telomere maintenance and tumor cell differentiation have been separately implicated in neuroblastoma malignancy. Their mechanistic connection is unclear. We analyzed neuroblastoma cell lines and morphologic subclones representing the adrenergic (ADRN) and mesenchymal (MES) differentiation states and uncovered sharp differences in their telomere protein and telomerase activity levels. Pharmacologic conversion of ADRN into MES cells elicited consistent and robust changes in the expression of telomere-related proteins. Conversely, stringent down-regulation of telomerase activity triggers the differentiation of ADRN into MES cells, which was reversible upon telomerase up-regulation. Interestingly, the MES differentiation state is associated with elevated levels of innate immunity factors, including key components of the DNA-sensing pathway. Accordingly, MES but not ADRN cells can mount a robust response to viral infections in vitro. A gene expression signature based on telomere and cell lineage-related factors can cluster neuroblastoma tumor samples into predominantly ADRN or MES-like groups, with distinct clinical outcomes. Our findings establish a strong mechanistic connection between telomere and differentiation and suggest that manipulating telomeres may suppress malignancy not only by limiting the tumor growth potential but also by inducing tumor cell differentiation and altering its immunogenicity.

Research Progress on the Antitumor Mechanism of Compound Kushen Injection

Compound Kushen Injection (CKI), as a clinical traditional Chinese medicine preparation, has prominent antitumor effect but with several side effects. A large number of studies have shown that CKI plays an antitumor role by regulating tumor cell proliferation, inducing tumor cell differentiation and apoptosis, inhibiting tumor cell invasion and metastasis, reducing tumor angiogenesis, regulating the immunity, and so on. Clinically, CKI is widely used to treat various tumors, where it is often combined with surgery, chemotherapy, radiotherapy, targeted therapy, and other antitumor treatments. This article reviews the antitumor mechanism of CKI and the progress of its clinical application in order to provide a theoretical basis for further clinical application.

Phosphorylation of OCT4 Serine 236 Inhibits Germ Cell Tumor Growth by Inducing Differentiation.

Simple SummaryOctamer-binding transcription factor 4 (OCT4) plays an important role in early embryonic development, but is rarely expressed in adults. However, in many cancer cells, this gene is re-expressed, making the cancer malignant. This present study revealed that inhibiting OCT4 transcriptional activity induces cancer cell differentiation and growth retardation. Specifically, when the phosphorylation of OCT4 serine 236 increases by interfering with the binding of protein phosphatase 1 (PP1) to OCT4, OCT4 loses its transcriptional activity and cancer cells differentiate. Therefore, this study presents the basis for the development of protein-protein interaction inhibitors that inhibit the binding of OCT4 and PP1 for cancer treatment. Octamer-binding transcription factor 4 (Oct4) plays an important role in maintaining pluripotency in embryonic stem cells and is closely related to the malignancies of various cancers. Although posttranslational modifications of Oct4 have been widely studied, most of these have not yet been fully characterized, especially in cancer. In this study, we investigated the role of phosphorylation of serine 236 of OCT4 [OCT4 (S236)] in human germ cell tumors (GCTs). OCT4 was phosphorylated at S236 in a cell cycle-dependent manner in a patient sample and GCT cell lines. The substitution of endogenous OCT4 by a mimic of phosphorylated OCT4 with a serine-to-aspartate mutation at S236 (S236D) resulted in tumor cell differentiation, growth retardation, and inhibition of tumor sphere formation. GCT cells expressing OCT4 S236D instead of endogenous OCT4 were similar to cells with OCT4 depletion at the mRNA transcript level as well as in the phenotype. OCT4 S236D also induced tumor cell differentiation and growth retardation in mouse xenograft experiments. Inhibition of protein phosphatase 1 by chemicals or short hairpin RNAs increased phosphorylation at OCT4 (S236) and resulted in the differentiation of GCTs. These results reveal the role of OCT4 (S236) phosphorylation in GCTs and suggest a new strategy for suppressing OCT4 in cancer.

Inhibition of airway remodeling and inflammatory response by Icariin in asthma

BackgroundIcariin (ICA) is the major active ingredient extracted from Chinese herbal medicine Epimedium, which has the effects of improving cardiovascular function, inducing tumor cell differentiation and increasing bone formation. It is still rarely reported that ICA can exert its therapeutic potential in asthma via anti-airway remodeling. The point of the study was to estimate the role of ICA in anti-.airway remodeling and its possible mechanism of action in a mouse ovalbumin.(OVA)-induced asthma model.MethodsHematoxylin and Eosin Staining were performed for measuring airway remodeling related indicators. ELISA, Western blot and Immunohistochemistr-.y (IHC) were used for analyzing the level of protein. RT-PCR was used for analyzing the level of mRNA.ResultsOn days 1 and 8, mice were sensitized to OVA by intraperitoneal injection. From day 16 to day 43, previously sensitized mice were exposed to OVA once daily by nebulizer. Interventions were performed orally with ICA (ICA low, medium and high dose groups) or dexamethasone 1 h prior to each OVA exposure. ICA improves pulmonary function, attenuates pulmonary inflammation and airway remodeling in mice exposed to OVA. Histological and Western blot analysis of the lungs show that ICA suppressed transforming growth factor beta 1 and vascular endothelial growth factor expression. Increase in interleukin 13 and endothelin-1 in serum and bronchoalveolar lavage fluid in OVA-induced asthmatic mice are also decreased by ICA. ICA attenuates airway smooth muscle cell proliferation, as well as key factors in the MAPK/Erk pathway.ConclusionsThe fact that ICA can alleviate OVA-induced asthma at least partly through inhibition of ASMC proliferation via MAPK/Erk pathway provides a solid theoretical basis for ICA as a replacement therapy for asthma. These data reveal the underlying reasons of the use of ICA-rich herbs in Traditional Chinese Medicine to achieve good results in treating asthma.

CBMT-11. HIGH MITOCHONDRIAL DNA COPY NUMBER IS ASSOCIATED WITH LONGER SURVIVAL IN YOUNG PATIENTS WITH GLIOBLASTOMA

Abstract Young patients (< 40 years-old) with glioblastoma (GB) may carry IDH1/2 mutations or rarely, H3F3A/HIST1H3B mutations. Some instead harbor chromosome (chr) 7 gain, chr 10 loss, and EGFR amplification (amp). IDH1/2 mutations are associated with longer survival in contrast to H3F3A/HIST1H3B mutations. Novel reliable prognostic factors are needed in GB. Mitochondria (mt) are responsible for ATP production through oxidative phosphorylation. High mtDNA copy number (CN) has been associated with variable outcomes in cancer. The mtDNA-CN was assessed by RT Q-PCR in 66 GB from patients 18 to 40 years-old. Whole mitochondrial genome sequencing was performed in 18/66 GB. 17/66 (25.8%) cases harbored IDH1-R132H mutation; 29/66 (44%) had chr 7 gain/chr 10 loss and/or EGFRamp; 4/66 (6%) harbored H3F3A/HIST1H3B mutations. The remaining cases (24.2%) had no key genetic alterations. The mtDNA/nuclearDNA ratio was subdivided into groups: Low and High according to the median (mtDNA-CN median 194.9). 33 patients displayed a low ratio (≤ median) whereas 33 displayed a high ratio (> median). The overall survival in the High vs Low group was significantly longer in the whole cohort (Log-rank test, 31.8 vs 14.2 months, p= 0.019) and the chr7+/chr10-/EGFRamp subgroup (37.8 vs 12.1 months; p= 0.0117). There was still a trend towards longer survival in the High vs Low group within the other genetic subgroups (IDH-mutant; no genetic alteration) except for the H3-mutant GB (4 patients). Analyses on 232 patients 18 to 84 years-old showed that among patients < 56 years-old, the High group (58 cases) had a longer survival compared to the Low group (59 cases) (27.3 vs 15 months; p= 0.023). High mtDNA level is linked to oxidative metabolism (which decreases tumor aggressiveness) and cell differentiation. Increasing mtDNA-CN might induce tumor cell differentiation and slow disease progression. In conclusion, mtDNA-CN may be a novel prognostic biomarker in GB.

Functional mechanism of Ginsenosides on tumor growth and metastasis.

Ginsengs, has long been used as one medicinal herb in China for more than two thousand years. Many studies have shown that ginsengs have preventive and therapeutic roles for cancer, and play a good complementary role in cancer treatment. Ginsenosides, as most important constituents of ginseng, have been extensively investigated and emphasized in cancer chemoprevention and therapeutics. However, the functional mechanism of Ginsenosides on cancer is not well known. This review will focus on introducing the functional mechanisms of ginsenosides and their metabolites, which regulate signaling pathways related with tumor growth and metastasis. Ginsenosides inhibit tumor growth via upregulating tumor apoptosis, inducing tumor cell differentiation and targeting cancer stem cells. In addition, Ginsenosides regulate tumor microenvironment via suppressing tumor angiogenesis-related proteins and pathways. Structural modification of ginsenosides and their administration alone or combinations with other Chinese medicines or chemical medicines have recently been developed to be a new therapeutic strategy for cancer.

Correlation of serum lactate dehydrogenase and alkaline phosphatase in different histological grades of head and neck squamous cell carcinoma and premalignant lesions.

Head neck cancer (HNCA) in North-East India accounts for 54.48% cancers at all sites, one of the highest in the country. Increased serum lactate dehydrogenase (LDH) activity is considered as a marker of cellular necrosis while serum alkaline phosphatase (ALP) is recognized as an important marker of induction of tumor cell differentiation. Considering the importance and need of biomarker in HNCA and there being no previous study on tumor markers from this highly prevalent region, we intended to examine the role of serum LDH and ALP in head and neck squamous cell carcinoma (HNSCC) and epithelial precursor lesions (EPLs) and also to find their correlation with the different histological grades of tumor. This is a prospective observational study on patients with HNSCC and precancerous lesions attending Department of ENT of a Teaching Hospital. Serum LDH and ALP was measured in HNSCC, EPL and control groups and the results were statistically analyzed and compared using analysis of variance, Pearson correlation coefficient, and sensitivity-specificity analysis. Serum LDH was found to be a significant marker of HNSCC. Total serum LDH level was high in both premalignant and HNSCC cases. There was a significant correlation between serum LDH and grades of HNSCC showing highest levels of expression in moderately differentiated SCC. Elevated serum LDH was also seen in erythroleukoplakia, leukoplakia, and verrucous lesion, but serum ALP levels were not significant. This is the first study from this highly prevalent region of HNCA showing that serum LDH could be regarded as a biomarker for malignant and premalignant conditions of the head and neck.

Abstract B126: AG-881, a brain penetrant, potent, pan-mutant IDH (mIDH) inhibitor for use in mIDH solid and hematologic malignancies

Abstract AG-881 is an orally available, brain penetrant, potent, small-molecule inhibitor of isocitrate dehydrogenase (IDH) 1 and IDH2 mutant proteins. Small-molecule inhibition of the mutant IDH (mIDH) protein represents a targeted approach to cancer treatment for patients who harbor an IDH1 and/or an IDH2 mutation. Direct inhibition of the gain-of-function activity of the mIDH protein is intended to inhibit the production of the oncogenic metabolite D-2-hydroxyglutarate (2-HG) and induce tumor cell differentiation. Biochemical studies of AG-881 demonstrate that it has low nanomolar potency inhibition (IC50) against multiple mIDH homodimer and heterodimer enzymes. It is a rapid-equilibrium inhibitor of mIDH1-R132H and mIDH2-R172K homodimer enzymes and is a slow-binding inhibitor of mIDH2-R140Q homodimer and wild type (wt) IDH1/mIDH1-R132H, wtIDH2/mIDH2-R140Q, and wtIDH2/mIDH2-R172K heterodimers. The potency against mIDH1 and mIDH2 enzymes has also been shown in cell lines and primary human patient samples. The IC50 range for 2-HG inhibition by AG-881 was 0.04-22 nM in cells expressing mIDH1-R132C, mIDH1-R132G, mIDH1-R132H, or mIDH1-R132S mutations and was 7-14 nM and 130 nM in cells expressing mIDH2-R140Q and mIDH2-R172K mutations, respectively. The treatment of these mIDH cell lines or primary human acute myeloid leukemia samples with AG-881 led to the onset of cellular differentiation. The pharmacokinetics of AG-881 are characterized by rapid oral absorption and low total body plasma clearance in mice (0.406 L/hr/kg) and rats (0.289 L/hr/kg). Because of these favorable properties, a series of in vivo pharmacology studies were conducted with AG-881 in mouse xenograft models. In these studies, dose-response relationships for the reduction in 2-HG in tumor by AG-881 were established. Twice-daily dosing of AG-881 in the HT1080 (mIDH1-R132C) and U87 (mIDH2-R140Q) mouse models reduced tumor 2-HG levels by >96% at doses ≥30 mg/kg. In the orthotopic glioma model (mIDH1-R132H), brain tumor 2-HG levels were reduced by >97% at doses ≥0.1 mg/kg. Based on in vivo exposure-response analyses, plasma AG-881 AUC0-24hr values of 402 hr•ng/mL and 45,200 hr•ng/mL are projected to result in sustained 97% reduction in tumor 2-HG levels in the glioma indication and the non-glioma solid and liquid tumor indications, respectively. AG-881 also exhibits excellent brain penetration, with brain-to-plasma ratios ranging from 0.62 to 1.96 in mice and 1.11 to 1.48 in rats (based on AUC0-24hr), and has an acceptable preclinical safety profile that supports clinical testing. Taken together, these data show that AG-881 is a potent inhibitor of the mIDH1 and mIDH2 proteins and suppresses 2-HG production in enzymatic, cell-based, and in vivo systems. Pharmacology studies support that suppression of 2-HG levels by AG-881 results in alterations of cellular downstream markers, leading to a release from blockage of tumor cell differentiation. AG-881 is currently in phase 1 clinical development in patients with an IDH1 and/or IDH2-mutation who have advanced solid tumors including gliomas (ClinicalTrials.gov NCT02481154), and advanced hematologic malignancies (ClinicalTrials.gov NCT02492737). Citation Format: Katharine Yen, Zenon Konteatis, Zhihua Sui, Erin Artin, Lenny Dang, Kimberly Straley, Erica Tobin, Carl Campos, Hua Yang, Raj Nagaraja, Yue Chen, Hyeryun Kim, Camelia Gliser, Brandon Nicolay, Andrew Olaharski, Lee Silverman, Scott Biller, Shinsan M. Su, Ingo Mellinghoff, Janeta Popovici-Muller. AG-881, a brain penetrant, potent, pan-mutant IDH (mIDH) inhibitor for use in mIDH solid and hematologic malignancies [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr B126.

Oxymatrine induces nasopharyngeal cancer cell death through inhibition of PI3K/AKT and NF‑κB pathways.

Oxymatrine may inhibit tumor cell proliferation, induce cell cycle arrest, promote apoptosis, induce tumor cell differentiation and fight against tumor angiogenesis, as well as inhibit tumor invasion and metastasis. The present study aimed to investigate the anticancer effects of oxymatrine on nasopharyngeal cancer (NPC) cell death, and the underlying molecular mechanisms of these effects. NPC HK‑1 cells were incubated overnight and treated with oxymatrine (0, 2, 4, 6 and 8mg/ml) for 1, 2 or 3days. The results demonstrated that oxymatrine significantly inhibited NPC cell proliferation in a time‑ and dose‑dependent manner. Oxymatrine treatment also induced apoptosis, induced the activities of caspase‑3 and caspase‑9, promoted p53 and Bax protein expression, and suppressed cyclin D protein expression in these cells. The protein expression levels of phosphoinositide 3 kinase (PI3K), phosphorylated (p)‑AKT, p‑mammalian target of rapamycin, p‑p70 ribosomal protein S6 kinase and nuclear factor (NF)‑κB were significantly downregulated by oxymatrine treatment. In conclusion, results from the present study suggested that oxymatrine may induce NPC cell death through the inhibition of PI3K/AKT and NF‑κB signaling pathways.

Citrate Suppresses Tumor Growth in Multiple Models through Inhibition of Glycolysis, the Tricarboxylic Acid Cycle and the IGF-1R Pathway

In this study we have tested the efficacy of citrate therapy in various cancer models. We found that citrate administration inhibited A549 lung cancer growth and additional benefit accrued in combination with cisplatin. Interestingly, citrate regressed Ras-driven lung tumors. Further studies indicated that citrate induced tumor cell differentiation. Additionally, citrate treated tumor samples showed significantly higher infiltrating T-cells and increased blood levels of numerous cytokines. Moreover, we found that citrate inhibited IGF-1R phosphorylation. In vitro studies suggested that citrate treatment inhibited AKT phosphorylation, activated PTEN and increased expression of p-eIF2a. We also found that p-eIF2a was decreased when PTEN was depleted. These data suggest that citrate acts on the IGF-1R-AKT-PTEN-eIF2a pathway. Additionally, metabolic profiling suggested that both glycolysis and the tricarboxylic acid cycle were suppressed in a similar manner in vitro in tumor cells and in vivo but only in tumor tissue. We reproduced many of these observations in an inducible Her2/Neu-driven breast cancer model and in syngeneic pancreatic tumor (Pan02) xenografts. Our data suggests that citrate can inhibit tumor growth in diverse tumor types and via multiple mechanisms. Dietary supplementation with citrate may be beneficial as a cancer therapy.

RANK Signaling Blockade Reduces Breast Cancer Recurrence by Inducing Tumor Cell Differentiation.

RANK expression is associated with poor prognosis in breast cancer even though its therapeutic potential remains unknown. RANKL and its receptor RANK are downstream effectors of the progesterone signaling pathway. However, RANK expression is enriched in hormone receptor negative adenocarcinomas, suggesting additional roles for RANK signaling beyond its hormone-dependent function. Here, to explore the role of RANK signaling once tumors have developed, we use the mouse mammary tumor virus-Polyoma Middle T (MMTV-PyMT), which mimics RANK and RANKL expression patterns seen in human breast adenocarcinomas. Complementary genetic and pharmacologic approaches demonstrate that therapeutic inhibition of RANK signaling drastically reduces the cancer stem cell pool, decreases tumor and metastasis initiation, and enhances sensitivity to chemotherapy. Mechanistically, genome-wide expression analyses show that anti-RANKL therapy promotes lactogenic differentiation of tumor cells. Moreover, RANK signaling in tumor cells negatively regulates the expression of Ap2 transcription factors, and enhances the Wnt agonist Rspo1 and the Sca1-population, enriched in tumor-initiating cells. In addition, we found that expression of TFAP2B and the RANK inhibitor, OPG, in human breast cancer correlate and are associated with relapse-free tumors. These results support the use of RANKL inhibitors to reduce recurrence and metastasis in breast cancer patients based on its ability to induce tumor cell differentiation. Cancer Res; 76(19); 5857-69. ©2016 AACR.

Developmental Stage-Specific Embryonic Induction of HepG2 Cell Differentiation.

Although hepatocellular carcinoma cells can sometimes undergo differentiation in an embryonic microenvironment, the mechanism is poorly understood. The developmental stage-specific embryonic induction of tumor cell differentiation was investigated. Both chick and mouse liver extracts and hepatoblast-enriched cells at different developmental stages were used to treat human hepatoma HepG2 cells, and the effects on the induction of differentiation were evaluated. The nuclear factors controlling differentiation, hepatocyte nuclear factor (HNF)-4α, HNF-1α, HNF-6 and upstream stimulatory factor-1 (USF-1), and the oncogene Myc and alpha-fetoprotein (AFP) were measured. HNF-4α RNA interference was used to verify the role of HNF-4α. Embryonic induction effects were further tested in vivo by injecting HepG2 tumor cells into immunodeficient nude mice. The 9-11-days chick liver extracts and 13.5-14.5-days mouse hepatoblast-enriched cells could inhibit proliferation and induce differentiation of HepG2 cells, leading to either death or maturation to hepatocytes. The maturation of surviving HepG2 cells was confirmed by increases in the expressions of HNF-4α, HNF-1α, HNF-6, and USF-1, and decreases in Myc and AFP. The embryonic induction of HepG2 cell maturation could be attenuated by HNF-4α RNA interference. Furthermore, the 13.5-days mouse hepatoblast culture completely eliminated HepG2 tumors with inhibited Myc and induced HNF-4α, confirming this embryonic induction effect in vivo. This study demonstrated that developmental stage-specific embryonic induction of HepG2 cell differentiation might help in understanding embryonic differentiation and oncogenesis.

E804 induces growth arrest, differentiation and apoptosis of glioblastoma cells by blocking Stat3 signaling.

Glioblastoma, the most common type of primary malignant brain tumor, is a devastating disease associated with a median survival of approximately 12 months. Here, we have tested E804, the commercially available indirubin derivatives, against U251 and U87 glioblastoma cells. Treatment with E804 significantly inhibits the growth of human glioblastoma cells lines via induction of differentiation and apoptosis. Differentiation induction is coupled with increased expression of glial fibriliary acidic protein, a marker for mature astrocytes. Apoptosis is associated with activation of Caspase 3 and reduction of Bcl-xL and Mcl-1. Furthermore, we demonstrate that E804 reduces signal transducer and activator of transcription-3 (Stat3) signaling to a remarkable extent, suggesting that inactivation of Stat3, at least in part, mediates the effects of this indirubin derivative. Consistently, reduction of Stat3 activity promotes E804-mediated anti-tumor effects, whereas overexpression of Stat3C mutant recues cell apoptosis induced by E804. Taken together, our results indicate that E804 can effectively suppress tumor cell growth, induce tumor cell differentiation and apoptosis mediated partially by Stat3 signaling pathway, suggesting that E804 could be useful for a potential anti-glioblastoma therapeutic approach.

Reducing DNA methylation suppresses colon carcinogenesis by inducing tumor cell differentiation.

The forced reduction of global DNA methylation suppresses tumor development in several cancer models in vivo. Nevertheless, the mechanisms underlying these suppressive effects remain unclear. In this report, we describe our findings showing that a genome-wide reduction in the DNA methylation levels induces cellular differentiation in association with decreased cell proliferation in Apc (Min/+) mouse colon tumor cells in vivo. Colon tumor-specific DNA methylation at Cdx1 is reduced in the DNA-hypomethylated tumors accompanied by Cdx1 derepression and an increased expression of intestinal differentiation-related genes. Furthermore, a histological analysis revealed that Cdx1 derepression in the DNA-hypomethylated tumors is correlated with the differentiation of colon tumor cells. Similarly, the treatment of human colon cancer cell lines with a hypomethylating agent induces differentiation-related genes, including CDX1. We herein propose that DNA demethylation exerts a tumor suppressive effect in the colon by inducing tumor cell differentiation.

Comparative study of Coptidis Rhizoma and Aconiti Kusnezoffii Radix on cell differentiation in lewis lung cancer

Coptidis Rhizoma and Aconiti Kusnezoffii Radix represent hot Chinese medicine and cold Chinese medicine respectively. The purpose of this study is to observe the differentiation effect of Coptidis Rhizoma and Aconiti Kusnezoffii Radix on lewis lung cancer and compare effect of hot Chinese medicine and cold Chinese medicine on tumor progression. In this study, the rat serum containing Coptidis Rhizoma or Aconiti Kusnezoffii Radix was prepared to treat lewis lung cancer cells in vitro, and effects of the serum containing Coptidis Rhizoma or Aconiti Kusnezoffii Radix on cell differentiation, proliferation, adhesion, succinic dehydrogenase (SDH) activity and gap-junction intercellular communication (GJIC) were investigated. In vivo, the subcutaneous implant model and pulmonary metastasis model of lewis lung cancer were established. Tumor bearing mice were taken water decoction of coptis chinensis or aconite by intragastric administration bid for four weeks, and the influences of coptis chinensis and aconite on tumor progression were evaluated by body temperature, blood oxygen saturation, red cell ATPase, blood rheology, intratumor hypoxia, capillary permeability and GJIC. The results showed that the serum containing aconite could induce cell differentiation, inhibit cell proliferation and migration, promote SDH activity and GJIC in lewis lung cancer cells. The serum containing Coptidis Rhizoma increased cell adhesion and decreased SDH activity and GJIC without cell differentiation although it also suppressed cell proliferation. Aconiti Kusnezoffii Radix water decoction could keep body temperature, blood oxygen saturation, red cell ATPase and blood rheology, and improve intratumor hypoxia, capillary permeability and GJIC in tumor bearing mice, which led to slower tumor growth and less metastasis. Coptidis Rhizoma water decoction decreased body temperature, blood oxygen saturation, red cell ATPase, blood rheology and GJIC, and promoted intratumor hypoxia and capillary permeability, which resulted to more tumor metastasis although it also prevented tumor growth. These results suggested that the hot Chinese medicine could induce tumor cell differentiation and prevent tumor poison invagination, which is better for tumor treatment than cold Chinese medicine.