DCLK1-Mediated Regulation of Invadopodia Dynamics and Matrix Metalloproteinase Trafficking Drives Invasive Progression in Head and Neck Squamous Cell Carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is a major health concern due to its high mortality from poor treatment responses and locoregional tumor invasion into life sustaining structures in the head and neck. A deeper comprehension of HNSCC invasion mechanisms holds the potential to inform targeted therapies that may enhance patient survival. We previously reported that doublecortin like kinase 1 (DCLK1) regulates invasion of HNSCC cells. Here, we tested the hypothesis that DCLK1 regulates proteins within invadopodia to facilitate HNSCC invasion. Invadopodia are specialized subcellular protrusions secreting matrix metalloproteinases that degrade the extracellular matrix (ECM). Through a comprehensive proteome analysis comparing DCLK1 control and shDCLK1 conditions, our findings reveal that DCLK1 plays a pivotal role in regulating proteins that orchestrate cytoskeletal and ECM remodeling, contributing to cell invasion. Further, we demonstrate in TCGA datasets that DCLK1 levels correlate with increasing histological grade and lymph node metastasis. We identified higher expression of DCLK1 in the leading edge of HNSCC tissue. Knockdown of DCLK1 in HNSCC reduced the number of invadopodia, cell adhesion and colony formation. Using super resolution microscopy, we demonstrate localization of DCLK1 in invadopodia and colocalization with mature invadopodia markers TKS4, TKS5, cortactin and MT1-MMP. We carried out phosphoproteomics and validated using immunofluorescence and proximity ligation assays, the interaction between DCLK1 and motor protein KIF16B. Pharmacological inhibition or knockdown of DCLK1 reduced interaction with KIF16B, secretion of MMPs, and cell invasion. This research unveils a novel function of DCLK1 within invadopodia to regulate the trafficking of matrix degrading cargo. The work highlights the impact of targeting DCLK1 to inhibit locoregional invasion, a life-threatening attribute of HNSCC.

Acryl-3,5-bis(2,4-difluorobenzylidene)-4-piperidone targeting cellular JUN proto-oncogene, AP-1 transcription factor subunit inhibits head and neck squamous cell carcinoma progression.

Aim: Head and neck squamous cell carcinoma (HNSCC) is the seventh most common cancer worldwide with a survival rate below fifty percent. Addressing meager therapeutic options, a series of small molecule inhibitors were screened for antitumor efficacy. The most potent analog, acryl-3,5-bis(2,4-difluorobenzylidene)-4-piperidone (DiFiD; A-DiFiD), demonstrated strong cellular JUN proto-oncogene, activator protein 1 (AP-1) transcription factor subunit (JUN, c-Jun) antagonism. c-Jun, an oncogenic transcription factor, promotes cancer progression, invasion, and adhesion; high (JUN) mRNA expression correlates with poorer HNSCC survival. Methods: Four new small molecules were generated for cytotoxicity screening in HNSCC cell lines. A-DiFiD-treated HNSCC cells were assessed for cytotoxicity, colony formation, invasion, migration, and adhesion. Dot blot array was used to identify targets. Phospho-c-Jun (p-c-Jun) expression was analyzed using immunoblotting. The Cancer Genome Atlas (TCGA) head and neck cancer datasets were utilized to determine overall patient survival. The Clinical Proteomic Tumor Analysis Consortium (CPTAC) datasets interfaced with University of Alabama at Birmingham Cancer Data Analysis Portal (UALCAN) were analyzed to determine protein levels of c-Jun in HNSCC patients and correlate levels with patient. Results: Of the small molecules tested, A-DiFiD was the most potent in HNSCC lines, while demonstrating low half-maximal drug inhibitory concentration (IC50) in non-malignant Het-1A cells. Additionally, A-DiFiD abrogated cell invasion, migration, and colony formation. Phospho-kinase in vitro array demonstrated A-DiFiD reduced p-c-Jun. Likewise, a time dependent reduction in p-c-Jun was observed starting at 3 min post A-DiFiD treatment. TCGA Firehose Legacy vs. recurrent and metastatic head and neck cancer reveal a nearly 3% DNA amplification in recurrent/metastatic tumor compared to below 1% in primary tumors that had no lymph node metastasis. CPTAC analysis show higher tumor c-Jun levels compared to normal. Patients with high JUN expression had significantly reduced 3-year survival. Conclusions: A-DiFiD targets c-Jun, a clinical HNSCC driver, with potent anti-tumor effects.

The Role of STATs in Ovarian Cancer: Exploring Their Potential for Therapy.

Ovarian cancer (OvCa) is a deadly gynecologic malignancy that presents many clinical challenges due to late-stage diagnoses and the development of acquired resistance to standard-of-care treatment protocols. There is an increasing body of evidence suggesting that STATs may play a critical role in OvCa progression, resistance, and disease recurrence, and thus we sought to compile a comprehensive review to summarize the current state of knowledge on the topic. We have examined peer reviewed literature to delineate the role of STATs in both cancer cells and cells within the tumor microenvironment. In addition to summarizing the current knowledge of STAT biology in OvCa, we have also examined the capacity of small molecule inhibitor development to target specific STATs and progress toward clinical applications. From our research, the best studied and targeted factors are STAT3 and STAT5, which has resulted in the development of several inhibitors that are under current evaluation in clinical trials. There remain gaps in understanding the role of STAT1, STAT2, STAT4, and STAT6, due to limited reports in the current literature; as such, further studies to establish their implications in OvCa are necessitated. Moreover, due to the deficiency in our understanding of these STATs, selective inhibitors also remain elusive, and therefore present opportunities for discovery.

Cancer-Associated Fibroblasts: Master Tumor Microenvironment Modifiers.

Cancer cells rely on the tumor microenvironment (TME), a composite of non-malignant cells, and extracellular matrix (ECM), for survival, growth, and metastasis. The ECM contributes to the biomechanical properties of the surrounding tissue, in addition to providing signals for tissue development. Cancer-associated fibroblasts (CAFs) are stromal cells in the TME that are integral to cancer progression. Subtypes of CAFs across a variety of cancers have been revealed, and each play a different role in cancer progression or suppression. CAFs secrete signaling molecules and remodel the surrounding ECM by depositing its constituents as well as degrading enzymes. In cancer, a remodeled ECM can lead to tumor-promoting effects. Not only does the remodeled ECM promote growth and allow for easier metastasis, but it can also modulate the immune system. A better understanding of how CAFs remodel the ECM will likely yield novel therapeutic targets. In this review, we summarize the key factors secreted by CAFs that facilitate tumor progression, ECM remodeling, and immune suppression.

The Contribution of the Human Oral Microbiome to Oral Disease: A Review.

The oral microbiome is an emerging field that has been a topic of discussion since the development of next generation sequencing and the implementation of the human microbiome project. This article reviews the current literature surrounding the oral microbiome, briefly highlighting most recent methods of microbiome characterization including cutting edge omics, databases for the microbiome, and areas with current gaps in knowledge. This article also describes reports on microorganisms contained in the oral microbiome which include viruses, archaea, fungi, and bacteria, and provides an in-depth analysis of their significant roles in tissue homeostasis. Finally, we detail key bacteria involved in oral disease, including oral cancer, and the current research surrounding their role in stimulation of inflammatory cytokines, the role of gingival crevicular fluid in periodontal disease, the creation of a network of interactions between microorganisms, the influence of the planktonic microbiome and cospecies biofilms, and the implications of antibiotic resistance. This paper provides a comprehensive literature analysis while also identifying gaps in knowledge to enable future studies to be conducted.

Doublecortin-like kinase 1 is a therapeutic target in squamous cell carcinoma.

Doublecortin like kinase 1 (DCLK1) plays a crucial role in several cancers including colon and pancreatic adenocarcinomas. However, its role in squamous cell carcinoma (SCC) remains unknown. To this end, we examined DCLK1 expression in head and neck SCC (HNSCC) and anal SCC (ASCC). We found that DCLK1 is elevated in patient SCC tissue, which correlated with cancer progression and poorer overall survival. Furthermore, DCLK1 expression is significantly elevated in human papilloma virus negative HNSCC, which are typically aggressive with poor responses to therapy. To understand the role of DCLK1 in tumorigenesis, we used specific shRNA to suppress DCLK1 expression. This significantly reduced tumor growth, spheroid formation, and migration of HNSCC cancer cells. To further the translational relevance of our studies, we sought to identify a selective DCLK1 inhibitor. Current attempts to target DCLK1 using pharmacologic approaches have relied on nonspecific suppression of DCLK1 kinase activity. Here, we demonstrate that DiFiD (3,5-bis [2,4-difluorobenzylidene]-4-piperidone) binds to DCLK1 with high selectivity. Moreover, DiFiD mediated suppression of DCLK1 led to G2/M arrest and apoptosis and significantly suppressed tumor growth of HNSCC xenografts and ASCC patient derived xenografts, supporting that DCLK1 is critical for SCC growth.

Immunoglobin A Deficiency and Squamous Cell Carcinoma With a Rare Presentation as Anal Cancer.

Selective immunoglobin A deficiency (IgAD) is the most common immunodeficiency disorder in the western world. Cancer is the most common cause of death in these individuals. Various cases have been reported of squamous cell carcinoma (SCC) in IgAD at sites like skin, oral cavity, and lung. Here we present a rare case of SCC occurring as anal cancer. No other reports to our knowledge describe this rare presentation. A 54-year-old Caucasian woman with asymptomatic partial IgAD presented with a palpable anal mass. Further evaluation showed stage IIIa SCC anal cancer (T1N1M0). Additional workup showed positive human papilloma virus (HPV) serology and positive HPV immunohistochemistry studies. The patient achieved complete response with chemoradiation with her most recent imaging and anorectal exam showing no evidence of cancer recurrence at 3 years follow-up. This case highlights the association between IgAD and malignancy. Although IgAD is the most common primary antibody deficiency, this patient's case presents a rare instance of anal SCC in an IgA-deficient individual. Studies show an association between HPV infection and SCC, but few include IgA-deficient individuals. Patients with IgAD and other immunodeficiencies are at higher risk for HPV infection and therefore may be at a higher risk of SCC. With widespread use of the HPV vaccine, the medical community should be aware of its importance in cancer prevention for these patients. Further studies are needed to evaluate relationships between IgAD, HPV infections, SCC cancer, and the role that the HPV vaccine has in cancer prophylaxis.

Multicellular contractility contributes to the emergence of mesothelioma nodules.

Malignant pleural mesothelioma (MPM) has an overall poor prognosis and unsatisfactory treatment options. MPM nodules, protruding into the pleural cavity may have growth and spreading dynamics distinct that of other solid tumors. We demonstrate that multicellular aggregates can develop spontaneously in the majority of tested MPM cell lines when cultured at high cell density. Surprisingly, the nodule-like aggregates do not arise by excessive local cell proliferation, but by myosin II-driven cell contractility. Prominent actin cables, spanning several cells, are abundant both in cultured aggregates and in MPM surgical specimens. We propose a computational model for in vitro MPM nodule development. Such a self-tensioned Maxwell fluid exhibits a pattern-forming instability that was studied by analytical tools and computer simulations. Altogether, our findings may underline a rational for targeting the actomyosin system in MPM.

DNA repair gene expression is increased in HPV positive head and neck squamous cell carcinomas.

The incidence of head and neck squamous cell carcinomas (HNSCCs) is rising in developed countries. This is driven by an increase in HNSCCs caused by high-risk human papillomavirus (HPV) infections or HPV + HNSCCs. Compared to HNSCCs not caused by HPV (HPV- HNSCCs), HPV + HNSCCs are more responsive to therapy and associated with better oncologic outcomes. As a result, the HPV status of an HNSCC is an important determinant in medical management. One method to determine the HPV status of an HNSCC is increased expression of p16 caused by the HPV E7 oncogene. We identified novel expression changes in HPV + HNSCCs. A comparison of gene expression among HPV+ and HPV- HNSCCs in The Cancer Genome Atlas demonstrated increased DNA repair gene expression in HPV + HNSCCs. Further, DNA repair gene expression correlated with HNSCC survival. Immunohistochemical analysis of a novel HNSCC microarray confirmed that DNA repair protein abundance is elevated in HPV + HNSCCs.

Cucurbitacin B and I inhibits colon cancer growth by targeting the Notch signaling pathway.

Cancer stem cells (CSCs) have the ability to self-renew and induce drug resistance and recurrence in colorectal cancer (CRC). As current chemotherapy doesn't eliminate CSCs completely, there is a need to identify novel agents to target them. We investigated the effects of cucurbitacin B (C-B) or I (C-I), a natural compound that exists in edible plants (bitter melons, cucumbers, pumpkins and zucchini), against CRC. C-B or C-I inhibited proliferation, clonogenicity, induced G2/M cell-cycle arrest and caspase-mediated-apoptosis of CRC cells. C-B or C-I suppressed colonosphere formation and inhibited expression of CD44, DCLK1 and LGR5. These compounds inhibited notch signaling by reducing the expression of Notch 1-4 receptors, their ligands (Jagged 1-2, DLL1,3,4), γ-secretase complex proteins (Presenilin 1, Nicastrin), and downstream target Hes-1. Molecular docking showed that C-B or C-I binds to the ankyrin domain of Notch receptor, which was confirmed using the cellular thermal shift assay. Finally, C-B or C-I inhibited tumor xenograft growth in nude mice and decreased the expression of CSC-markers and notch signaling proteins in tumor tissues. Together, our study suggests that C-B and C-I inhibit colon cancer growth by inhibiting Notch signaling pathway.

Diphenylbutylpiperidine Antipsychotic Drugs Inhibit Prolactin Receptor Signaling to Reduce Growth of Pancreatic Ductal Adenocarcinoma in Mice.

BACKGROUND & AIMS: Prolactin (PRL) signaling is up-regulated in hormone-responsive cancers. The PRL receptor (PRLR) is a class I cytokine receptor that signals via the Janus kinase (JAK)-signal transducer and activator of transcription and mitogen-activated protein kinase pathways to regulate cell proliferation, migration, stem cell features, and apoptosis. Patients with pancreatic ductal adenocarcinoma (PDAC) have high plasma levels of PRL. We investigated whether PRLR signaling contributes to the growth of pancreatic tumors in mice. METHODS: We used immunohistochemical analyses to compare levels of PRL and PRLR in multitumor tissue microarrays. We used structure-based virtual screening and fragment-based drug discovery to identify compounds likely to bind PRLR and interfere with its signaling. Human pancreatic cell lines (AsPC-1, BxPC-3, Panc-1, and MiaPaCa-2), with or without knockdown of PRLR (clustered regularly interspaced short palindromic repeats or small hairpin RNA), were incubated with PRL or penfluridol and analyzed in proliferation and spheroid formation. C57BL/6 mice were given injections of UNKC-6141 cells, with or without knockdown of PRLR, into pancreas, and tumor development was monitored for 4 weeks, with some mice receiving penfluridol treatment for 21 days. Human pancreatic tumor tissues were implanted into interscapular fat pads of NSG mice, and mice were given injections of penfluridol daily for 28 days. Nude mice were given injections of Panc-1 cells, xenograft tumors were grown for 2 weeks, and mice were then given intraperitoneal penfluridol for 35 days. Tumors were collected from mice and analyzed by histology, immunohistochemistry, and immunoblots. RESULTS: Levels of PRLR were increased in PDAC compared with nontumor pancreatic tissues. Incubation of pancreatic cell lines with PRL activated signaling via JAK2-signal transducer and activator of transcription 3 and extracellular signal-regulated kinase, as well as formation of pancospheres and cell migration; these activities were not observed in cells with PRLR knockdown. Pancreatic cancer cells with PRLR knockdown formed significantly smaller tumors in mice. We identified several diphenylbutylpiperidine-class antipsychotic drugs as agents that decreased PRL-induced JAK2 signaling; incubation of pancreatic cancer cells with these compounds reduced their proliferation and formation of panco spheres. Injections of 1 of these compounds, penfluridol, slowed the growth of xenograft tumors in the different mouse models, reducing proliferation and inducing autophagy of the tumor cells. CONCLUSIONS: Levels of PRLR are increased in PDAC, and exposure to PRL increases proliferation and migration of pancreatic cancer cells. Antipsychotic drugs, such as penfluridol, block PRL signaling in pancreatic cancer cells to reduce their proliferation, induce autophagy, and slow the growth of xenograft tumors in mice. These drugs might be tested in patients with PDAC.

Targeting transcription factor TCF4 by γ-Mangostin, a natural xanthone.

Given that colon cancer is the third most common cancer in incidence and cause of death in the United States, and current treatment modalities are insufficient, there is a need to develop novel agents. Towards this, here we focus on γ-Mangostin, a bioactive compound present in the Mangosteen (Garcinia mangostana) fruit. γ-Mangostin suppressed proliferation and colony formation, and induced cell cycle arrest and apoptosis of colon cancer cell lines. Further, γ-Mangostin inhibited colonosphere formation. Molecular docking and CETSA (Cellular thermal shift assay) binding assays demonstrated that γ-Mangostin interacts with transcription factor TCF4 (T-Cell Factor 4) at the ß-catenin binding domain with the binding energy of -5.5 Kcal/mol. Moreover, γ-Mangostin treatment decreased TCF4 expression and reduced TCF reporter activity. The compound also suppressed the expression of Wnt signaling target proteins cyclin D1 and c-Myc, and stem cell markers such as LGR5, DCLK1 and CD44. To determine the effect of γ-Mangostin on tumor growth in vivo, we administered nude mice harboring HCT116 tumor xenografts with 5 mg/Kg of γ-Mangostin intraperitoneally for 21 days. γ-Mangostin treatment significantly suppressed tumor growth, with notably lowered tumor volume and weight. In addition, western blot analysis revealed a significant decrease in the expression of TCF4 and its downstream targets such as cyclin D1 and c-Myc. Together, these data suggest that γ-Mangostin inhibits colon cancer growth through targeting TCF4. γ-Mangostin may be a potential therapeutic agent for colon cancer.

The role of the innate and adaptive immune response in HPV-associated oropharyngeal squamous cell carcinoma.

Human papilloma virus (HPV) has been implicated in the development of oropharyngeal squamous cell carcinoma (OPSCC) and is directly attributed to its increasing incidence. The immune microenvironment surrounding HPV-associated OPSCC tumors is complex and plays a critical role in the carcinogenic process. The neoplastic mechanism includes cells of the innate immunity such as macrophages, and dendritic cells as well as cells of the adaptive immune process such as CD8+ T-cells. The intricate interactions between these two arms of the immune system allow for a pro-inflammatory and pro-tumorigenic environment. Intensive efforts are underway to gain a greater understanding of the mechanisms involved in the immune system's role in tumor development. This study seeks to summarize the current knowledge pertaining to role of the innate and adaptive immune response in HPV-associated OPSCC. LEVEL OF EVIDENCE: 3a.

Pleotropic role of RNA binding protein CELF2 in autophagy induction.

We previously reported that ionizing radiation (IR) mediates cell death through the induction of CUGBP elav-like family member 2 (CELF2), a tumor suppressor. CELF2 is an RNA binding protein that modulates mRNA stability and translation. Since IR induces autophagy, we hypothesized that CELF2 regulates autophagy-mediated colorectal cancer (CRC) cell death. For clinical relevance, we determined CELF2 levels in The Cancer Genome Atlas (TCGA). Role of CELF2 in radiation response was carried out in CRC cell lines by immunoblotting, immunofluorescence, autophagic vacuole analyses, RNA stability assay, quantitative polymerase chain reaction and electron microscopy. In vivo studies were performed in a xenograft tumor model. TCGA analyses demonstrated that compared to normal tissue, CELF2 is expressed at significantly lower levels in CRC, and is associated with better overall 5-year survival in patients receiving radiation. Mechanistically, CELF2 increased levels of critical components of the autophagy cascade including Beclin-1, ATG5, and ATG12 by modulating mRNA stability. CELF2 also increased autophagic flux in CRC. IR significantly induced autophagy in CRC which correlates with increased levels of CELF2 and autophagy associated proteins. Silencing CELF2 with siRNA, mitigated IR induced autophagy. Moreover, knockdown of CELF2 in vivo conferred tumor resistance to IR. These studies elucidate an unrecognized role for CELF2 in inducing autophagy and potentiating the effects of radiotherapy in CRC.

Autophagy-dependent secretion: mechanism, factors secreted, and disease implications.

Although best understood as a degradative pathway, recent evidence demonstrates pronounced involvement of the macroautophagic/autophagic molecular machinery in cellular secretion. With either overexpression or inhibition of autophagy mediators, dramatic alterations in the cellular secretory profile occur. This affects secretion of a plethora of factors ranging from cytokines, to granule contents, and even viral particles. Encompassing a wide range of secreted factors, autophagy-dependent secretion is implicated in diseases ranging from cancer to neurodegeneration. With a growing body of evidence shedding light onto the molecular mediators, this review delineates the molecular machinery involved in selective targeting of the autophagosome for either degradation or secretion. In addition, we summarize the current understanding of factors and cargo secreted through this unconventional route, and describe the implications of this pathway in both health and disease. Abbreviations: BECN1, beclin 1; CAF, cancer associated fibroblast; CUPS, compartment for unconventional protein secretion; CXCL, C-X-C motif chemokine ligand; ER, endoplasmic reticulum; FGF2, fibroblast growth factor 2; HMGB1, high mobility group box 1; IDE, insulin degrading enzyme; IL, Interleukin; MAP1LC3/LC3, microtubule associated protein 1 light chain 3; MAPS, misfolding associated protein secretion; MEF, mouse embryonic fibroblast; MTORC1, MTOR complex I; PtdIns, phosphatidyl inositol; SEC22B, SEC22 homolog B, vesicle trafficking protein (gene/pseudogene); SFV, Semliki forest virus; SNCA, synuclein alpha; SQSTM1, sequestosome 1; STX, Syntaxin; TASCC, TOR-associated spatial coupling compartment; TGFB, transforming growth factor beta; TRIM16, tripartite motif containing 16; UPS, unconventional protein secretion; VWF, von Willebrand factor.

Metastatic Tumor-in-a-Dish, a Novel Multicellular Organoid to Study Lung Colonization and Predict Therapeutic Response.

Metastasis is a major cause of cancer-related deaths. A dearth of preclinical models that recapitulate the metastatic microenvironment has impeded the development of therapeutic agents that are effective against metastatic disease. Because the majority of solid tumors metastasize to the lung, we developed a multicellular lung organoid that mimics the lung microenvironment with air sac-like structures and production of lung surfactant protein. We used these cultures, called primitive lung-in-a-dish (PLiD), to recreate metastatic disease using primary and established cancer cells. The metastatic tumor-in-a-dish (mTiD) cultures resemble the architecture of metastatic tumors in the lung, including angiogenesis. Pretreating PLiD with tumor exosomes enhanced cancer cell colonization. We next tested the response of primary and established cancer cells to current chemotherapeutic agents and an anti-VEGF antibody in mTiD against cancer cells in two-dimensional (2D) or 3D cultures. The response of primary patient-derived colon and ovarian tumor cells to therapy in mTiD cultures matched the response of the patient in the clinic, but not in 2D or single-cell-type 3D cultures. The sensitive mTiD cultures also produced significantly lower circulating markers for cancer similar to that seen in patients who responded to therapy. Thus, we have developed a novel method for lung colonization in vitro, a final stage in tumor metastasis. Moreover, the technique has significant utility in precision/personalized medicine, wherein this phenotypic screen can be coupled with current DNA pharmacogenetics to identify the ideal therapeutic agent, thereby increasing the probability of response to treatment while reducing unnecessary side effects. SIGNIFICANCE: A lung organoid that exhibits characteristics of a normal human lung is developed to study the biology of metastatic disease and therapeutic intervention.

Quantitative clinical outcomes of therapy for head and neck lymphedema.

PURPOSE: Head and neck surgery and radiation cause tissue fibrosis that leads to functional limitations and lymphedema. The objective of this study was to determine whether lymphedema therapy after surgery and radiation for head and neck cancer decreases neck circumference, increases cervical range of motion, and improves pain scores. METHODS AND MATERIALS: A retrospective review of all patients with squamous cell carcinoma of the oral cavity, oropharynx, or larynx who were treated with high-dose radiation therapy at a single center between 2011 and 2012 was performed. Patients received definitive or postoperative radiation for squamous cell carcinoma of the oral cavity, oropharynx, or larynx. Patients were referred to a single, certified, lymphedema therapist with specialty training in head and neck cancer after completion of radiation treatment and healing of acute toxicity (typically 1-3 months). Patients underwent at least 3 months of manual lymphatic decongestion and skilled fibrotic techniques. Circumferential neck measurements and cervical range of motion were measured clinically at 1, 3, 6, 9, and 12 months after completion of radiation therapy. Pain scores were also recorded. RESULTS: Thirty-four consecutive patients were eligible and underwent a median of 6 months of lymphedema therapy (Range, 3-12 months). Clinically measured total neck circumference decreased in all patients with 1 month of treatment. Cervical rotation increased by 30.2% on the left and 27.9% on the right at 1 month and continued to improve up to 44.6% and 55.3%, respectively, at 12 months. Patients undergoing therapy had improved pain scores from 4.3 at baseline to 2.0 after 1 month. CONCLUSIONS: Lymphedema therapy is associated with objective improvements in range of motion, neck circumference, and pain scores in the majority of patients.

Potent Antitumor Effects of a Combination of Three Nutraceutical Compounds.

Head and neck squamous cell carcinoma (HNSCC) is associated with low survival, and the current aggressive therapies result in high morbidity. Nutraceuticals are dietary compounds with few side effects. However, limited antitumor efficacy has restricted their application for cancer therapy. Here, we examine combining nutraceuticals, establishing a combination therapy that is more potent than any singular component, and delineate the mechanism of action. Three formulations were tested: GZ17-S (combined plant extracts from Arum palaestinum, Peganum harmala and Curcuma longa); GZ17-05.00 (16 synthetic components of GZ17-S); and GZ17-6.02 (3 synthetic components of GZ17S; curcumin, harmine and isovanillin). We tested the formulations on HNSCC proliferation, migration, invasion, angiogenesis, macrophage viability and infiltration into the tumor and tumor apoptosis. GZ17-6.02, the most effective formulation, significantly reduced in vitro assessments of HNSCC progression. When combined with cisplatin, GZ17-6.02 enhanced anti-proliferative effects. Molecular signaling cascades inhibited by GZ17-6.02 include EGFR, ERK1/2, and AKT, and molecular docking analyses demonstrate GZ17-6.02 components bind at distinct binding sites. GZ17-6.02 significantly inhibited growth of HNSCC cell line, patient-derived xenografts, and murine syngeneic tumors in vivo (P < 0.001). We demonstrate GZ17-6.02 as a highly effective plant extract combination and pave the way for future clinical application in HNSCC.

Cancer Stem Cell Metabolism and Potential Therapeutic Targets.

Malignant tumors contain heterogeneous populations of cells in various states of proliferation and differentiation. The presence of cancer stem or initiating cells is a well-established concept wherein quiescent and poorly differentiated cells within a tumor mass contribute to drug resistance, and under permissive conditions, are responsible for tumor recurrence and metastasis. A number of studies have identified molecular markers that are characteristic of tissue-specific cancer stem cells (CSCs). Isolation of CSCs has enabled studies on the metabolic status of CSCs. As metabolic plasticity is a hallmark of cancer cell adaptation, the intricacies of CSC metabolism and their phenotypic behavior are critical areas of research. Unlike normal stem cells, which rely heavily on oxidative phosphorylation (OXPHOS) as their primary source of energy, or cancer cells, which are primarily glycolytic, CSCs demonstrate a unique metabolic flexibility. CSCs can switch between OXPHOS and glycolysis in the presence of oxygen to maintain homeostasis and, thereby, promote tumor growth. Here, we review key factors that impact CSC metabolic phenotype including heterogeneity of CSCs across different histologic tumor types, tissue-specific variations, tumor microenvironment, and CSC niche. Furthermore, we discuss how targeting key players of glycolytic and mitochondrial pathways has shown promising results in cancer eradication and attenuation of disease recurrence in preclinical models. In addition, we highlight studies on other potential therapeutic targets including complex interactions within the microenvironment and cellular communications in the CSC niche to interfere with CSC growth, resistance, and metastasis.

Cancer-Associated Fibroblasts Drive Glycolysis in a Targetable Signaling Loop Implicated in Head and Neck Squamous Cell Carcinoma Progression.

Despite aggressive therapies, head and neck squamous cell carcinoma (HNSCC) is associated with a less than 50% 5-year survival rate. Late-stage HNSCC frequently consists of up to 80% cancer-associated fibroblasts (CAF). We previously reported that CAF-secreted HGF facilitates HNSCC progression; however, very little is known about the role of CAFs in HNSCC metabolism. Here, we demonstrate that CAF-secreted HGF increases extracellular lactate levels in HNSCC via upregulation of glycolysis. CAF-secreted HGF induced basic FGF (bFGF) secretion from HNSCC. CAFs were more efficient than HNSCC in using lactate as a carbon source. HNSCC-secreted bFGF increased mitochondrial oxidative phosphorylation and HGF secretion from CAFs. Combined inhibition of c-Met and FGFR significantly inhibited CAF-induced HNSCC growth in vitro and in vivo (P < 0.001). Our cumulative findings underscore reciprocal signaling between CAF and HNSCC involving bFGF and HGF. This contributes to metabolic symbiosis and a targetable therapeutic axis involving c-Met and FGFR.Significance: HNSCC cancer cells and CAFs have a metabolic relationship where CAFs secrete HGF to induce a glycolytic switch in HNSCC cells and HNSCC cells secrete bFGF to promote lactate consumption by CAFs. Cancer Res; 78(14); 3769-82. ©2018 AACR.