Cancer Biology Commons^™

Complex Role Of Microbiome In Pancreatic Tumorigenesis: Potential Therapeutic Implications, Suneetha Amara, Li V. Yang, Venkataswarup Tiriveedhi, Mahvish Muzaffar

Biology Faculty Research

Pancreatic cancer (PC) is the fourth leading cause of cancer-related mortality with limited diagnostic and therapeutic options. Although immunotherapy has shown promise in the treatment of several cancers, its role in pancreatic cancer is rather limited. Several studies have focused on determining the role of the tumor microenvironment with cancer-cell-intrinsic events and tumor-infiltrating immune cellular properties. However, in the past decade, there has been emerging research aimed at delineating the role of the host microbiome, including the metabolites from microbes and host responses, on pancreatic tumorigenesis. Importantly, there is emerging evidence suggesting the beneficial role of a gut microbiome transplant …

Low-Salt Diet Reduces Anti-Ctla4 Mediated Systemic Immune-Related Adverse Events While Retaining Therapeutic Efficacy Against Breast Cancer, Durga Khandekar, Debolanle O. Dahunsi, Isaac V. Manzanera Esteve, Sonya Reid, Jeffrey C. Rathmell, Jens M. Titze, Venkataswarup Tiriveedhi

Biology Faculty Research

Immune checkpoint inhibitor (ICI) therapy has revolutionized the breast cancer treatment landscape. However, ICI-induced systemic inflammatory immune-related adverse events (irAE) remain a major clinical challenge. Previous studies in our laboratory and others have demonstrated that a high-salt (HS) diet induces inflammatory activation of CD4+T cells leading to anti-tumor responses. In our current communication, we analyzed the impact of dietary salt modification on therapeutic and systemic outcomes in breast-tumor-bearing mice following anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA4) monoclonal antibody (mAb) based ICI therapy. As HS diet and anti-CTLA4 mAb both exert pro-inflammatory activation of CD4+T cells, we hypothesized that a combination of …

Association Of Oral Microbiota With Lung Cancer Risk In A Low-Income Population In The Southeastern Usa, Jiajun Shi, Yaohua Yang, Hua Xie, Xiaofei Wang, Jie Wu, Jirong Long, Regina Courtney, Xiao-Ou Shu, Wei Zheng, William J. Blot, Qiuyin Cai

Biology Faculty Research

Purpose

Oral microbiome plays an important role in oral health and systemic diseases, including cancer. We aimed to prospectively investigate the association of oral microbiome with lung cancer risk.

Methods

We analyzed 156 incident lung cancer cases (73 European Americans and 83 African Americans) and 156 individually matched controls nested within the Southern Community Cohort Study. Oral microbiota were assessed using 16S rRNA gene sequencing in pre-diagnostic mouth rinse samples. Paired t test and the permutational multivariate analysis of variance test were used to evaluate lung cancer risk association with alpha diversity or beta diversity, respectively. Conditional logistic regression models …

Cancer Salt Nostalgia, Aashish S. Allu, Venkataswarup Tiriveedhi

Biology Faculty Research

High-salt (sodium chloride) diets have been strongly associated with disease states and poor health outcomes. Traditionally, the impact of salt intake is primarily studied in cardiovascular diseases, hypertension and renal diseases; however, recently there has been increasing evidence demonstrating the role of salt in autoimmune diseases. Salt has been shown to modulate the inflammatory activation of immune cells leading to chronic inflammation-related ailments. To date, there is minimal evidence showing a direct correlation of salt with cancer incidence and/or cancer-related adverse clinical outcomes. In this review article, we will discuss the recent understanding of the molecular role of salt, and …

Ex Vivo High Salt Activated Tumor-Primed Cd4+T Lymphocytes Exert A Potent Anti-Cancer Response, Venkataswarup Tiriveedhi, Michael Ivy, Elbert L. Myles, Roy Zent, Jeffrey C. Rathmell, Jens M. Titze

Biology Faculty Research

Cell based immunotherapy is rapidly emerging as a promising cancer treatment. A modest increase in salt (sodium chloride) concentration in immune cell cultures is known to induce inflammatory phenotypic differentiation. In our current study, we analyzed the ability of salt treatment to induce ex vivo expansion of tumor-primed CD4 (cluster of differentiation 4)+T cells to an effector phenotype. CD4+T cells were isolated using immunomagnetic beads from draining lymph nodes and spleens from tumor bearing C57Bl/6 mice, 28 days post-injection of Py230 syngeneic breast cancer cells. CD4+T cells from non-tumor bearing mice were isolated from splenocytes of 12-week-old C57Bl/6 mice. These …

Inhibition Of The Spectraplakin Protein Microtubule Actin Crosslinking Factor 1 Sensitizes Glioblastomas To Radiation, Kala Bonner, Danielle Borlay, Orica Kutten, Quincy A. Quick

Biology Faculty Research

Background

Microtubule actin crosslinking factor 1 (MACF1) is a spectraplakin cytoskeletal crosslinking protein whose function and role in cancer biology has lacked investigation. Recent studies have identified MACF1 as a novel target in glioblastomas expressed in tissue from tumor patient explants but not normal brain tissue and when silenced has an antitumorigenic impact on these tumors. Radiation as a single agent therapy to treat glioblastomas has been used for decades and has done little to improve survival of individuals diagnosed with this disease. However, contemporary clinical radiotherapy protocols have provided evidence that combinatorial radiotherapy approaches confer a therapeutic benefit in …

Role Of Bet Inhibitors In Triple Negative Breast Cancers, Durga Khandekar, Venkataswarup Tiriveedhi

Biology Faculty Research

Bromodomain and extraterminal domain (BET) proteins have evolved as key multifunctional super-regulators that control gene expression. These proteins have been shown to upregulate transcriptional machinery leading to over expression of genes involved in cell proliferation and carcinogenesis. Based on favorable preclinical evidence of BET inhibitors in various cancer models; currently, 26 clinical trials are underway in various stages of study on various hematological and solid organ cancers. Unfortunately, preliminary evidence for these clinical studies does not support the application of BET inhibitors as monotherapy in cancer treatment. Furthermore, the combinatorial efficiency of BET inhibitors with other chemo-and immunotherapeutic agents remain …

Editorial: The Role Of Breast Cancer Stem Cells In Clinical Outcomes, Dayanidhi Raman, Amit K. Tiwari, Venkataswarup Tiriveedhi, Julie A. Rhoades

Biology Faculty Research

No abstract provided.

Perplexing Role Of P-Glycoprotein In Tumor Microenvironment, Kianna Robinson, Venkataswarup Tiriveedhi

Biology Faculty Research

Development of multidrug resistance (MDR) still remains a major obstacle to the long-term success of cancer therapy. P-glycoprotein (P-gp) is a well-identified membrane transporter with capability to efflux drug molecules out of the cancer cell leading to reduced efficiency of chemotherapy. Cancer cells upregulate P-gp expression as an adaptive response to evade chemotherapy mediated cell death. While several P-gp inhibitors have been discovered by in silico and pre-clinical studies, very few have successfully passed all phases of the clinical trials. Studies show that application of P-gp inhibitors in cancer therapy regimen following development of MDR achieved limited beneficial outcomes. While, …

Methylselenol Producing Selenocompounds Enhance The Efficiency Of Mammaglobin‑A Peptide Vaccination Against Breast Cancer Cells, Duaa Babaer, Mu Zheng, Michael T. Ivy, Roy Zent, Venkataswarup Tiriveedhi

Biology Faculty Research

Previous phase I DNA‑vaccine based clinical trials using Mammaglobin‑A (Mam‑A), a human breast tumor associated antigen (TAA), demonstrated that this agent was safe and efficient at treating patients with stage IV breast cancer. The long‑term success of cancer vaccines is limited by the diminished expression of human leukocyte antigen (HLA) class I molecules in the tumor microenvironment. The current study assessed the impact of various selenocompounds on the expression of HLA class I molecules in THP‑1 cells, an apparent proficient antigen that presents a human monocyte‑like cell line, and their eventual activation of MamA2.1 (HLA‑A2 immunodominant epitope of Mam‑A) specific …

Phospho Tensin Homolog In Human And Lipid Peroxides In Peripheral Blood Mononuclear Cells Following Exposure To Flavonoids, William Y. Boadi, Elbert L. Myles, Alekzander S. Garcia

Biology Faculty Research

Objectives: Studies have shown that human and peripheral blood mononuclear cells (PBMCs) are mostly used for research purposes to study several biochemical endpoints. The effects of the flavonoids, genistein, kaempferol, and quercetin on phospho tensin homolog (PTEN) levels in cancer cells (i.e., breast [BT549], lung [A549]), human embryonic kidney cells (HEK293), and the levels of lipid peroxides (LP) in PBMCs were respectively investigated.

Materials and methods: Cancer, kidney, and PBMCs from several donors were each exposed to each of the flavonoids at concentrations of 0, 5, 10, 15, 20, and 25 µM. Our hypotheses were that exposure of cancer and …

Immunogenicity Of Tumor Initiating Stem Cells: Potential Applications In Novel Anticancer Therapy, Durga Khandekar, Suneetha Amara, Venkataswarup Tiriveedhi

Biology Faculty Research

Tumor initiating stem cells (TISCs) are a subset of tumor cells, which are implicated in cancer relapse and resistance to chemotherapy. The metabolic programs that drive TISC functions are exquisitely unique and finely-tuned by various oncogene-driven transcription factors to facilitate pro-cancerous adaptive challenges. While this change in TISC metabolic machinery allows for the identification of associated molecular targets with diagnostic and prognostic value, these molecules also have a potential immunological application. Recent studies have shown that these TISC-associated molecules have strong antigenic properties enabling naïve CD8+T lymphocytes to differentiate into cytotoxic effector phenotype with anticancer potential. In spite of the …

High Salt Induces P-Glycoprotein Mediated Treatment Resistance In Breast Cancer Cells Through Store Operated Calcium Influx, Duaa Babaer, Suneetha Amara, Michael Ivy, Yan Zhao, Philip E. Lammers, Jens M. Titze, Venkataswarup Tiriveedhi

Biology Faculty Research

Recent evidence from our laboratory has demonstrated that high salt (Δ0.05 M NaCl) induced inflammatory response and cancer cell proliferation through salt inducible kinase-3 (SIK3) upregulation. As calcium influx is known to effect inflammatory response and drug resistance, we examined the impact of high salt on calcium influx in breast cancer cells. Treatment of MCF-7 and MDA-MB-231 cells with high salt induced an enhanced intracellular calcium intensity, which was significantly decreased by store operated calcium entry (SOCE) inhibitor co-treatment. Further, high salt induced P-glycoprotein (P-gp) mediated paclitaxel drug resistance in breast cancer cells. Murine tumor studies demonstrated that injection of …

Potential Anticancer Effect Of Prostratin Through Sik3 Inhibition, Dalal Alotaibi, Suneetha Amara, Terrance L. Johnson, Venkataswarup Tiriveedhi

Biology Faculty Research

Prostratin, a phorbol ester natural plant compound, has been demonstrated to exert an anti‑retroviral effect through activation of latent cluster of differentiation (CD)4+T lymphocytes and inhibition of viral entry into the cell through downregulation of chemokine receptor type 4 (CXCR4) expression. However, the potential effect of prostratin on cancer is yet to be defined. As CXCR4 is well known to induce cancer migration, it was hypothesized that prostratin induces an anti‑cancer effect through inhibition of CXCR4 expression. The authors previously demonstrated that high stimulating conditions (sub‑minimal IL‑17, 0.1 ng/ml, synergized with high salt, Δ0.05 M NaCl) promote breast cancer cell …

Critical Role Of Sik3 In Mediating High Salt And Il-17 Synergy Leading To Breast Cancer Cell Proliferation, Suneetha Amara, Ciera Majors, Bipradas Roy, Salisha Hill, Kristie L. Rose, Elbert L. Myles, Venkataswarup Tiriveedhi

Biology Faculty Research

Chronic inflammation is a well-known precursor for cancer development and proliferation. We have recently demonstrated that high salt (NaCl) synergizes with sub-effective interleukin (IL)-17 to induce breast cancer cell proliferation. However, the exact molecular mechanisms mediating this effect are unclear. In our current study, we adopted a phosphoproteomic-based approach to identify salt modulated kinase-proteome specific molecular targets. The phosphoprotemics based binary comparison between heavy labelled MCF-7 cells treated with high salt (Δ0.05 M NaCl) and light labelled MCF-7 cells cultured under basal conditions demonstrated an enhanced phosphorylation of Serine-493 of SIK3 protein. The mRNA transcript and protein expression analysis of …

Inflammatory Role Of High Salt Level In Tumor Microenvironment (Review), Suneetha Amara, Venkataswarup Tiriveedhi

Biology Faculty Research

Chronic inflammation is known to play a critical role in cancer development and progression. High salt is known to mediate several chronic inflammatory diseases including hypertension, myocardial infarction, neurological ischemic attack, autoimmune diseases and cancers. High salt level is shown to induce angiogenesis and immune-dysfunction, both of which play a direct role in cancer proliferation. Furthermore, salt has been suggested to enhance Warburg-like metabolic phenotype in cancer cells and at the same time also induce pro-tumor MΦ2-macrophage phenotype. Recent studies have identified several molecular targets such as tonicity specific transcript factor NFAT5/TonEBP, sodium ion channel γENaC, and vascular endothelial growth …

Inflammatory Role Of High Salt Level In Tumor Microenvironment (Review), Suneetha Amara, Venkataswarup Tiriveedhi

Biology Faculty Research

Chronic inflammation is known to play a critical role in cancer development and progression. High salt is known to mediate several chronic inflammatory diseases including hypertension, myocardial infarction, neurological ischemic attack, autoimmune diseases and cancers. High salt level is shown to induce angiogenesis and immune-dysfunction, both of which play a direct role in cancer proliferation. Furthermore, salt has been suggested to enhance Warburg-like metabolic phenotype in cancer cells and at the same time also induce pro-tumor MΦ2-macrophage phenotype. Recent studies have identified several molecular targets such as tonicity specific transcript factor NFAT5/TonEBP, sodium ion channel γENaC, and vascular endothelial growth …

The Five Immune Forces Impacting Dna-Based Cancer Immunotherapeutic Strategy, Suneetha Amara, Venkataswarup Tiriveedhi

Biology Faculty Research

DNA-based vaccine strategy is increasingly realized as a viable cancer treatment approach. Strategies to enhance immunogenicity utilizing tumor associated antigens have been investigated in several pre-clinical and clinical studies. The promising outcomes of these studies have suggested that DNA-based vaccines induce potent T-cell effector responses and at the same time cause only minimal side-effects to cancer patients. However, the immune evasive tumor microenvironment is still an important hindrance to a long-term vaccine success. Several options are currently under various stages of study to overcome immune inhibitory effect in tumor microenvironment. Some of these approaches include, but are not limited to, …

Microtubule Actin Cross-Linking Factor 1, A Novel Target In Glioblastoma, Najlaa Afghani, Toral Mehta, Jialiang Wang, Nan Tang, Omar Skalli, Quincy A. Quick

Biology Faculty Research

Genetic heterogeneity is recognized as a major contributing factor of glioblastoma resistance to clinical treatment modalities and consequently low overall survival rates. This genetic diversity results in variations in protein expression, both intratumorally and between individual glioblastoma patients. In this regard, the spectraplakin protein, microtubule actin cross-linking factor 1 (MACF1), was examined in glioblastoma. An expression analysis of MACF1 in various types of brain tumor tissue revealed that MACF1 was predominately present in grade III-IV astroctyomas and grade IV glioblastoma, but not in normal brain tissue, normal human astrocytes and lower grade brain tumors. Subsequent genetic inhibition experiments showed that …

Nfat5/Stat3 Interaction Mediates Synergism Of High Salt With Il-17 Towards Induction Of Vegf-A Expression In Breast Cancer Cells, Suneetha Amara, Dalal Alotaibi, Venkataswarup Tiriveedhi

Biology Faculty Research

Chronic inflammation has been considered an important player in cancer proliferation and progression. High salt (sodium chloride) levels have been considered a potent inducer of chronic inflammation. In the present study, the synergistic role of high salt with interleukin (IL)‑17 towards induction of the inflammatory and angiogenic stress factor vascular endothelial growth factor (VEGF)‑A was investigated. Stimulation of MCF-7 breast cancer cells with high salt (0.2 M NaCl) and sub‑minimal IL‑17 (1 ng/ml) enhanced the expression of VEGF-A (2.9 and 2.6-fold, respectively, P<0.05) compared with untreated cells. Furthermore, co‑treatment with both high salt and sub‑minimal IL‑17 led to a 5.9‑fold increase in VEGF‑A expression (P<0.01), thus suggesting a synergistic role of these factors. VEGF‑A promoter analysis and specific small interfering RNA knock‑down of transcription factors revealed that high salt induced VEGF‑A expression through nuclear factor of activated T‑cells (NFAT)5, while IL‑17 induced VEGF‑A expression via signal transducer and activator of transcription (STAT)3 signaling mechanisms. Treatment of normal human aortic endothelial cells with the supernatant of activated MCF‑7 cells enhanced cell migration and induced expression of migration‑specific factors, including vascular cell adhesion protein, β1 integrin and cluster of differentiation 31. These data suggest that high salt levels synergize with pro‑inflammatory IL‑17 to potentially induce cancer progression and metastasis through VEGF‑A expression. Therefore, low‑salt diet, anti‑NFAT5 and anti‑STAT3 therapies may provide novel avenues for enhanced efficiency of the current cancer therapy.

Oleanolic Acid Inhibits High Salt-Induced Exaggeration Of Warburg-Like Metabolism In Breast Cancer Cells, Suneetha Amara, Mu Zheng, Venkataswarup Tiriveedhi

Biology Faculty Research

Cancer cells have a proliferative advantage by utilizing intermediates of aerobic glycolysis (Warburg effect) for their macromolecule synthesis. Although the exact causes of this Warburg effect are unclear, high osmotic stress in solid tumor microenvironment is considered one of the important factors. Oleanolic acid (OA) is known to exert anti-inflammatory and anti-cancer effect. In our current studies, using breast cancer cell lines, we determined the protective role of OA in high salt-mediated osmotic stress-induced cancer growth. Hypertonic (0.16 M NaCl) culture conditions enhanced the cancer cell growth (26 %, p < 0.05) and aerobic glycolysis as marked by increased glucose consumption (34 %, p < 0.05) and lactate production (25 %, p < 0.05) over untreated cells. This effect was associated with increased expression and activity of key rate-limiting enzymes of aerobic glycolysis, namely hexokinase, pyruvate kinase type M2, and lactate dehydrogenase A. Interestingly, this high salt-mediated enhanced expression of aerobic glycolytic enzymes was efficiently reversed by OA along with the decreased cancer cell proliferation. In cancer cells, enhanced aerobic glycolysis is associated with the decreased mitochondrial activity and mitochondrial-associated caspase activity. As expected, high salt further inhibited the mitochondrial related cytochrome oxidase and caspase-3 activity. However, OA efficiently reversed the high salt-mediated inhibition of cytochrome oxidase, caspase activity, and pro-apoptotic Bax expression, thus suggesting that OA induced mitochondrial activity and enhanced apoptosis. Taken together, our data indicate that OA efficiently reverses the enhanced Warburg-like metabolism induced by high salt-mediated osmotic stress along with potential application of OA in anti-cancer therapy.

Sodium Channel Γenac Mediates Il-17 Synergized High Salt Induced Inflammatory Stress In Breast Cancer Cells, Suneetha Amara, Michael T. Ivy, Elbert L. Myles, Venkataswarup Tiriveedhi

Biology Faculty Research

Chronic inflammation is known to play a critical role in the development of cancer. Recent evidence suggests that high salt in the tissue microenvironment induces chronic inflammatory milieu. In this report, using three breast cancer-related cell lines, we determined the molecular basis of the potential synergistic inflammatory effect of sodium chloride (NaCl) with interleukin-17 (IL-17). Combined treatment of high NaCl (0.15M) with sub-effective IL-17 (0.1nM) induced enhanced growth in breast cancer cells along with activation of reactive nitrogen and oxygen (RNS/ROS) species known to promote cancer. Similar effect was not observed with equi-molar mannitol. This enhanced of ROS/RNS activity correlates …

Violacein Induces P44/42 Mitogen-Activated Protein Kinase‑Mediated Solid Tumor Cell Death And Inhibits Tumor Cell Migration, Toral Mehta, Koen Vercruysse, Terrance Johnson, Anthony Okechukwu Ejiofor, Elbert Myles, Quincy Antoine Quick

Biology Faculty Research

Microbial secondary metabolites have emerged as alternative novel drugs for the treatment of human cancers. Violacein, a purple pigment produced by Chromobacterium violaceum, was investigated in the present study for its anti‑tumor properties in tumor cell lines. Clinically applicable concentrations of violacein were demonstrated to inhibit the proliferative capacity of tumor cell lines according to a crystal violet proliferation assay. The underlying mechanism was the promotion of apoptotic cell death, as indicated by poly(ADP ribose) polymerase cleavage and p44/42 mitogen‑activated protein kinase signaling determined by western blot analysis. Collectively, this provided mechanistic evidence that violacein elicits extracellular-signal regulated kinase‑induced apoptosis …

Biological Activities Of Fusarochromanone: A Potent Anti-Cancer Agent, Elahe Mahdavian, Phillip Palyok, Steven Adelmund, Tara Williams-Hart, Brian D. Furmanski, Yoon-Jee Kim, Ying Gu, Mansoureh Barzegar, Yang Wu, Kaustubh N. Bhinge, Gopi K. Kolluru, Quincy A. Quick, Yong-Yu Liu, Christopher G. Kevil, Brian A. Salvatore, Shile Huang, John L. Clifford

Biology Faculty Research

Background

Fusarochromanone (FC101) is a small molecule fungal metabolite with a host of interesting biological functions, including very potent anti-angiogenic and direct anti-cancer activity.

Results

Herein, we report that FC101 exhibits very potent in-vitro growth inhibitory effects (IC₅₀ ranging from 10nM-2.5 μM) against HaCat (pre-malignant skin), P9-WT (malignant skin), MCF-7 (low malignant breast), MDA-231 (malignant breast), SV-HUC (premalignant bladder), UM-UC14 (malignant bladder), and PC3 (malignant prostate) in a time-course and dose-dependent manner, with the UM-UC14 cells being the most sensitive. FC101 induces apoptosis and an increase in proportion of cells in the sub-G1 phase in both HaCat and P9-WT …

Caspase-Dependent Signaling Underlies Glioblastoma Cell Death In Response To The Fungal Metabolite, Fusarochromanone, Elahe Mahdavian, Monique Marshall, Patrick M. Martin, Patrice Cagle, Brian A. Salvatore, Quincy A. Quick

Biology Faculty Research

Fungal metabolites continue to show promise as a viable class of anticancer agents. In the present study, we investigated the efficacy of the fungal metabolite, fusarochromanone (FC101), for its antitumor activities in glioblastomas, which have a median survival of less than two years and a poor clinical response to surgical resection, radiation therapy and chemotherapy. Using clinically applicable doses, we demonstrated that FC101 induced glioblastoma apoptotic cell death via caspase dependent signaling, as indicated by the cleavage of poly(ADP-ribose) polymerase, glioblastoma (PARP). FC101 also induced differential reactive oxygen species (ROS) levels in glioblastoma cells, contrasting a defined role of oxidative …