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1.
Build Environ ; 190: 107561, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33519043

ABSTRACT

The occupant density in buildings is one of the major and overlooked parameters affecting the energy consumption and virus transmission risk in buildings. HVAC systems energy consumption is highly dependent on the number of occupants. Studies on the transmission of COVID-19 virus have indicated a direct relationship between occupant density and COVID-19 infection risk. This study aims to seek the optimum occupant distribution patterns that account for the lowest number of infected people and minimum energy consumption. A university building located in Tehran has been chosen as a case study, due to its flexibility in performing various occupant distribution patterns. This multi-objective optimization problem, with the objective functions of energy consumption and COVID-19 infected people, is solved by NSGA-II algorithm. Energy consumption is evaluated by EnergyPlus, then it is supplied to the algorithm through a co-simulation communication between EnergyPlus and MATLAB. Results of this optimization algorithm for 5 consequent winter and summer days, represent optimum occupant distribution patterns, associated with minimum energy consumption and COVID-19 infected people for winter and summer. Building air exchange rate, class duration, and working hours of the university, as the COVID-19 controlling approaches were studied, and promising results have been obtained. It was concluded that an optimal population distribution can reduce the number of infected people by up to 56% and energy consumption by 32%. Furthermore, it was concluded that virtual learning is an excellent approach in universities to control the number of infections and energy consumption.

2.
BMC Cancer ; 19(1): 864, 2019 Aug 30.
Article in English | MEDLINE | ID: mdl-31470802

ABSTRACT

BACKGROUND: Bronchial carcinoids are neuroendocrine tumors that present as typical (TC) and atypical (AC) variants, the latter being more aggressive, invasive and metastatic. Studies of tumor initiating cell (TIC) biology in bronchial carcinoids has been hindered by the lack of appropriate in-vitro and xenograft models representing the bronchial carcinoid phenotype and behavior. METHODS: Bronchial carcinoid cell lines (H727, TC and H720, AC) were cultured in serum-free growth factor supplemented medium to form 3D spheroids and serially passaged up to the 3rd generation permitting expansion of the TIC population as verified by expression of stemness markers, clonogenicity in-vitro and tumorigenicity in both subcutaneous and orthotopic (lung) models. Acetazolamide (AZ), sulforaphane (SFN) and the AZ + SFN combination were evaluated for targeting TIC in bronchial carcinoids. RESULTS: Data demonstrate that bronchial carcinoid cell line 3rd generation spheroid cells show increased drug resistance, clonogenicity, and tumorigenic potential compared with the parental cells, suggesting selection and expansion of a TIC fraction. Gene expression and immunolabeling studies demonstrated that the TIC expressed stemness factors Oct-4, Sox-2 and Nanog. In a lung orthotopic model bronchial carcinoid, cell line derived spheroids, and patient tumor derived 3rd generation spheroids when supported by a stroma, showed robust tumor formation. SFN and especially the AZ + SFN combination were effective in inhibiting tumor cell growth, spheroid formation and in reducing tumor formation in immunocompromised mice. CONCLUSIONS: Human bronchial carcinoid tumor cells serially passaged as spheroids contain a higher fraction of TIC exhibiting a stemness phenotype. This TIC population can be effectively targeted by the combination of AZ + SFN. Our work portends clinical relevance and supports the therapeutic use of the novel AZ+ SFN combination that may target the TIC population of bronchial carcinoids.


Subject(s)
Acetazolamide/administration & dosage , Anticarcinogenic Agents/administration & dosage , Bronchial Neoplasms/drug therapy , Carcinoid Tumor/drug therapy , Isothiocyanates/administration & dosage , Neoplastic Stem Cells/drug effects , Acetazolamide/pharmacology , Animals , Anticarcinogenic Agents/pharmacology , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Bronchial Neoplasms/genetics , Bronchial Neoplasms/metabolism , Carcinoid Tumor/genetics , Carcinoid Tumor/metabolism , Cell Culture Techniques , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , Isothiocyanates/pharmacology , Mice , Nanog Homeobox Protein/genetics , Nanog Homeobox Protein/metabolism , Neoplastic Stem Cells/cytology , Neoplastic Stem Cells/metabolism , Octamer Transcription Factor-3/genetics , Octamer Transcription Factor-3/metabolism , SOXB1 Transcription Factors/genetics , SOXB1 Transcription Factors/metabolism , Spheroids, Cellular/cytology , Spheroids, Cellular/drug effects , Spheroids, Cellular/metabolism , Sulfoxides , Xenograft Model Antitumor Assays
3.
BMC Cancer ; 17(1): 156, 2017 02 24.
Article in English | MEDLINE | ID: mdl-28235409

ABSTRACT

BACKGROUND: Neuroblastoma (NB), a tumor of the primitive neural crest, despite aggressive treatment portends a poor long-term survival for patients with advanced high stage NB. New treatment strategies are required. METHODS: We investigated coordinated targeting of essential homeostatic regulatory factors involved in cancer progression, histone deacetylases (HDACs) and carbonic anhydrases (CAs). RESULTS: We evaluated the antitumor potential of the HDAC inhibitor (HDACi), pyridylmethyl-N-{4-[(2-aminophenyl)-carbamoyl]-benzyl}-carbamate (MS-275) in combination with a pan CA inhibitor, acetazolamide (AZ) on NB SH-SY5Y, SK-N-SH and SK-N-BE(2) cells. The key observation was that the combination AZ + MS-275 significantly inhibited growth, induced cell cycle arrest and apoptosis, and reduced migration capacity of NB cell line SH-SY5Y. In addition, this combination significantly inhibited tumor growth in vivo, in a pre-clinical xenograft model. Evidence was obtained for a marked reduction in tumorigenicity and in the expression of mitotic, proliferative, HIF-1α and CAIX. NB xenografts of SH-SY5Y showed a significant increase in apoptosis. CONCLUSION: MS-275 alone at nanomolar concentrations significantly reduced the putative cancer stem cell (CSC) fraction of NB cell lines, SH-SY5Y and SK-N-BE(2), in reference to NT2/D1, a teratocarcinoma cell line, exhibiting a strong stem cell like phenotype in vitro. Whereas stemness genes (OCT4, SOX2 and Nanog) were found to be significantly downregulated after MS-275 treatment, this was further enhanced by AZ co-treatment. The significant reduction in initial tumorigenicity and subsequent abrogation upon serial xenografting suggests potential elimination of the NB CSC fraction. The significant potentiation of MS-275 by AZ is a promising therapeutic approach and one amenable for administration to patients given their current clinical utility.


Subject(s)
Acetazolamide/pharmacology , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Benzamides/pharmacology , Neuroblastoma/drug therapy , Pyridines/pharmacology , Acetazolamide/therapeutic use , Animals , Antineoplastic Agents/therapeutic use , Benzamides/therapeutic use , Carbonic Anhydrase Inhibitors/pharmacology , Carbonic Anhydrase Inhibitors/therapeutic use , Cell Line , Cell Movement/drug effects , Cell Proliferation/drug effects , Drug Therapy, Combination , Female , Histone Deacetylase Inhibitors/pharmacology , Histone Deacetylase Inhibitors/therapeutic use , Humans , Mice , Pyridines/therapeutic use , Treatment Outcome , Xenograft Model Antitumor Assays
4.
Am J Respir Cell Mol Biol ; 52(2): 183-92, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25019941

ABSTRACT

In normal lung, the predominant cytoplasmic carbonic anhydrase (CA) isozyme (CAII) is highly expressed in amine- and peptide-producing pulmonary neuroendocrine cells where its role involves CO2 sensing. Here, we report robust cytoplasmic expression of CAII by immunohistochemistry in the tumor cells of different native neuroendocrine tumor (NET) types, including typical and atypical carcinoids and small-cell lung carcinomas, and in NET and non-NET tumor cell lines. Because, in both pulmonary neuroendocrine cell and related NETs, the hypercapnia-induced secretion of bioactive serotonin (5-hydroxytryptamine) is mediated by CAII, we investigated the role of CAII in the biological behavior of carcinoid cell line H727 and the type II cell-derived A549 using both in vitro clonogenicity and in vivo xenograft model. We show that short hairpin RNA-mediated down-regulation of CAII resulted in significant reduction in clonogenicity of H727 and A549 cells in vitro, and marked suppression of tumor growth in vivo. CAII-short hairpin RNA cell-derived xenografts showed significantly reduced mitosis (phosphohistone H3 marker) and proliferation associated antigen Ki-67 (Ki67 marker), and significantly increased apoptosis by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Using an apoptosis gene array, we found no association with caspases 3 and 8, but with a novel association of CAII-mediated apoptosis with specific mitochondrial apoptosis-associated proteins. Furthermore, these xenografts showed a significantly reduced vascularization (CD31 marker). Thus, CAII may play a critical role in NET lung tumor growth, angiogenesis, and survival, possibly via 5-hydroxytryptamine, known to drive autocrine tumor growth. As such, CAII is a potential therapeutic target for the difficult-to-treat lung NETs.


Subject(s)
Apoptosis/physiology , Carbonic Anhydrase II/metabolism , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Neuroendocrine Tumors/metabolism , Cell Line, Tumor , Humans , Immunohistochemistry/methods , Ki-67 Antigen/metabolism , Lung/metabolism , Neuroendocrine Tumors/pathology , RNA, Small Interfering/metabolism , Serotonin/metabolism
5.
J Magn Reson Imaging ; 41(3): 806-13, 2015 Mar.
Article in English | MEDLINE | ID: mdl-24591227

ABSTRACT

PURPOSE: To investigate the potential of manganese (Mn)-enhanced MRI for sensitive detection and delineation of tumors that demonstrate little enhancement on Gd-DTPA. MATERIALS AND METHODS: Eighteen nude rats bearing 1 to 2 cm in diameter orthotopic breast tumors (ZR75 and LM2) were imaged on a 3 Tesla (T) clinical scanner. Gd-DTPA was administered intravenously and MnCl2 subcutaneously, both at 0.05 mmol/kg. T1 -weighted imaging and T1 measurements were performed precontrast, 10 min post-Gd-DTPA, and 24 h post-MnCl2 . Tumors were excised and histologically assessed using H&E (composition and necrosis) and CD34 (vascularity). RESULTS: Most tumors (78%) demonstrated little enhancement (< 20% change in R1 ) on Gd-DTPA. MnCl2 administration achieved greater and more uniform enhancement throughout the tumor mass (i.e., not restricted to the tumor periphery), with R1 changing over 20% in 72% of tumors. MnCl2 -induced R1 changes compared with Gd-induced changes were significantly greater in both ZR75 (P < 0.01) and LM2 tumors (P < 0.05). Histology confirmed very low vascularity in both tumor models, and necrotic areas were well delineated only on Mn-enhanced MRI. CONCLUSION: Mn-enhanced MRI is a promising approach for detection of low-Gd-enhancing tumors.


Subject(s)
Breast Neoplasms/diagnosis , Contrast Media , Gadolinium DTPA , Image Enhancement/methods , Magnetic Resonance Imaging , Manganese , Analysis of Variance , Animals , Disease Models, Animal , Female , Humans , Rats , Rats, Nude
6.
Mol Imaging ; 132014.
Article in English | MEDLINE | ID: mdl-25060340

ABSTRACT

Very early cancer detection is the key to improving cure. Our objective was to investigate manganese (Mn)-enhanced magnetic resonance imaging (MRI) for very early detection and characterization of breast cancers. Eighteen NOD scid gamma mice were inoculated with MCF7, MDA, and LM2 breast cancer cells and imaged periodically on a 3 T scanner beginning on day 6. T1-weighted imaging and T1 measurements were performed before and 24 hours after administering MnCl2. At the last imaging session, Gd-DTPA was administered and tumors were excised for histology (hematoxylin-eosin and CD34 staining). All mice, except for two inoculated with MCF7 cells, developed tumors. Tumors enhanced uniformly on Mn and showed clear borders. Early small tumors (≤ 5 mm3) demonstrated the greatest enhancement with a relative R1 (1/T1) change of 1.57 ± 0.13. R1 increases correlated with tumor size (r  =  -.34, p  =  .04). Differences in R1 increases among the three tumor subtypes were most evident in early tumors. Histology confirmed uniform cancer cell distribution within tumor masses and vasculature in the periphery, which was consistent with rim-like enhancement on Gd-DTPA. Mn-enhanced MRI is a promising approach for detecting very small breast cancers in vivo and may be valuable for very early cancer detection.


Subject(s)
Chlorides , Early Detection of Cancer/methods , Magnetic Resonance Imaging/methods , Mammary Neoplasms, Experimental/diagnosis , Manganese Compounds , Animals , Cell Line, Tumor , Contrast Media , Female , Gadolinium DTPA , Humans , MCF-7 Cells , Mice , Mice, SCID
7.
Clin Implant Dent Relat Res ; 26(1): 78-87, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37849436

ABSTRACT

OBJECTIVE: To evaluate patient safety, implants survival and implant stability of the bisphosphonate (zoledronate) as a coating on dental implants in patients requiring oral rehabilitation in the posterior maxilla. MATERIALS AND METHODS: In this multicenter, double-blind, randomized controlled study, 62 patients were randomized to receive either zoledronate-coated or uncoated control implants in the premolar or molar area of the maxilla, using a one stage-protocol. Due to dropouts and exclusion 49 patients completed the study. The implants were examined by resonance frequency analysis (RFA) using an implant stability quotient (ISQ) scale at the time of insertion, and at 8 weeks, and after 12 weeks prior to prosthetic restoration. Radiographs were taken prior to surgery, directly after insertion, and during the follow-up at 12 weeks, 6 months, and 1 year to analyze changes in marginal bone levels (MBL). Finally, all complications and adverse effects (AE) were observed and recorded. RESULTS: Out of 62 included patients, 49 patients completed the study. No AE were reported by patients receiving zoledronate-coated implants. There was no statistically significant difference between the zoledronate-coated or uncoated implant groups when comparing ISQ levels at insertion and after 12 weeks of healing, the mean of the ISQ values demonstrated a change of 4.64 (95% confidence interval: 15.46; 5.79, p = 0.43) between the two groups. At 8- and 12-weeks, ISQ values remained stable (range 62-70). Radiographic analysis showed no statistically significant difference in MBL between the two implant groups after 1 year of loading neither at the mesial side (p = 0.99) or the distal side (p = 0.97). MBL for coated implants were 0.57 mm at the mesial side and 0.46 mm at the distal side. For the uncoated implants, MBL was 0.48 mm at the mesial side and 0.47 mm at the distal side. CONCLUSION: The zoledronate-coated dental implants are safe to use in a one-stage surgery protocol in patients requiring oral rehabilitation in the posterior maxilla, after 1 year of loading. There were no statically significant changes in implant stability and marginal bone levels measured by intraoral radiographs in comparison to uncoated control implants.


Subject(s)
Dental Implants , Immediate Dental Implant Loading , Jaw, Edentulous, Partially , Mouth, Edentulous , Humans , Zoledronic Acid , Dental Implantation, Endosseous/methods , Immediate Dental Implant Loading/methods , Jaw, Edentulous, Partially/surgery , Mouth, Edentulous/surgery , Dental Restoration Failure , Dental Prosthesis, Implant-Supported , Maxilla/surgery
8.
Cancers (Basel) ; 16(15)2024 Jul 31.
Article in English | MEDLINE | ID: mdl-39123447

ABSTRACT

Hepatocellular carcinoma (HCC), the predominant form of liver cancer, is associated with high mortality rates both in the United States and globally. Despite current advances in immunotherapy regimens, there is a scarcity of biomarkers to guide therapy selection. Alpha-fetoprotein (AFP) and glypican-3 have been proposed as biomarkers for HCC, but they do not provide any prognostic benefit for modeling disease progression. Agrin, a secreted proteoglycan, is frequently overexpressed in HCC and plays prominent role(s) in the liver tumor microenvironment (TME) to promote hepatocarcinogenesis. Here we employed a pilot single-center retrospective investigation to assess the prognostic value of agrin in HCC. Our evidence suggests that elevated serum agrin levels are associated with poor prognosis and performance among HCC patients. Multivariate Cox regression models indicate that secreted agrin serves as a better prognostic indicator compared to AFP that is significantly correlated with other secreted biomarkers (e.g., IL6). Cumulatively, this work demonstrates a promising clinical value of agrin in the detection and prognosis of HCC.

9.
Stem Cells ; 30(8): 1685-95, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22689594

ABSTRACT

Human embryonic stem cells (hESCs) have been reported to exert cytoprotective activity in the area of tissue injury. However, hypoxia/oxidative stress prevailing in the area of injury could activate p53, leading to death and differentiation of hESCs. Here we report that when exposed to hypoxia/oxidative stress, a small fraction of hESCs, namely the SSEA3+/ABCG2+ fraction undergoes a transient state of reprogramming to a low p53 and high hypoxia inducible factor (HIF)-2α state of transcriptional activity. This state can be sustained for a period of 2 weeks and is associated with enhanced transcriptional activity of Oct-4 and Nanog, concomitant with high teratomagenic potential. Conditioned medium obtained from the post-hypoxia SSEA3+/ABCG2+ hESCs showed cytoprotection both in vitro and in vivo. We termed this phenotype as the "enhanced stemness" state. We then demonstrated that the underlying molecular mechanism of this transient phenotype of enhanced stemness involved high Bcl-2, fibroblast growth factor (FGF)-2, and MDM2 expression and an altered state of the p53/MDM2 oscillation system. Specific silencing of HIF-2α and p53 resisted the reprogramming of SSEA3+/ABCG2+ to the enhanced stemness phenotype. Thus, our studies have uncovered a unique transient reprogramming activity in hESCs, the enhanced stemness reprogramming where a highly cytoprotective and undifferentiated state is achieved by transiently suppressing p53 activity. We suggest that this transient reprogramming is a form of stem cell altruism that benefits the surrounding tissues during the process of tissue regeneration.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors/metabolism , Embryonic Stem Cells/physiology , Tumor Suppressor Protein p53/metabolism , Animals , Cell Differentiation/physiology , Cell Hypoxia/physiology , Cell Survival/physiology , Embryonic Stem Cells/cytology , Embryonic Stem Cells/metabolism , Humans , Mice , Mice, Inbred NOD , Mice, SCID , Oxidative Stress/physiology , RNA, Small Interfering/administration & dosage , RNA, Small Interfering/genetics , Rats , Tumor Suppressor Protein p53/genetics , Up-Regulation
10.
BMC Cancer ; 13: 378, 2013 Aug 08.
Article in English | MEDLINE | ID: mdl-23927827

ABSTRACT

BACKGROUND: Bronchial carcinoids are pulmonary neuroendocrine cell-derived tumors comprising typical (TC) and atypical (AC) malignant phenotypes. The 5-year survival rate in metastatic carcinoid, despite multiple current therapies, is 14-25%. Hence, we are testing novel therapies that can affect the proliferation and survival of bronchial carcinoids. METHODS: In vitro studies were used for the dose-response (AlamarBlue) effects of acetazolamide (AZ) and sulforaphane (SFN) on clonogenicity, serotonin-induced growth effect and serotonin content (LC-MS) on H-727 (TC) and H-720 (AC) bronchial carcinoid cell lines and their derived NOD/SCID mice subcutaneous xenografts. Tumor ultra structure was studied by electron microscopy. Invasive fraction of the tumors was determined by matrigel invasion assay. Immunohistochemistry was conducted to study the effect of treatment(s) on proliferation (Ki67, phospho histone-H3) and neuroendocrine phenotype (chromogranin-A, tryptophan hydroxylase). RESULTS: Both compounds significantly reduced cell viability and colony formation in a dose-dependent manner (0-80 µM, 48 hours and 7 days) in H-727 and H-720 cell lines. Treatment of H-727 and H-720 subcutaneous xenografts in NOD/SCID mice with the combination of AZ + SFN for two weeks demonstrated highly significant growth inhibition and reduction of 5-HT content and reduced the invasive capacity of H-727 tumor cells. In terms of the tumor ultra structure, a marked reduction in secretory vesicles correlated with the decrease in 5-HT content. CONCLUSIONS: The combination of AZ and SFN was more effective than either single agent. Since the effective doses are well within clinical range and bioavailability, our results suggest a potential new therapeutic strategy for the treatment of bronchial carcinoids.


Subject(s)
Acetazolamide/pharmacology , Antineoplastic Agents/pharmacology , Bronchial Neoplasms/metabolism , Bronchial Neoplasms/pathology , Carbonic Anhydrase Inhibitors/pharmacology , Carcinoid Tumor/metabolism , Carcinoid Tumor/pathology , Isothiocyanates/pharmacology , Acetazolamide/administration & dosage , Animals , Antineoplastic Agents/administration & dosage , Bronchial Neoplasms/drug therapy , Carbonic Anhydrase Inhibitors/administration & dosage , Carcinoid Tumor/drug therapy , Cell Line, Tumor , Cell Survival/drug effects , Disease Models, Animal , Dose-Response Relationship, Drug , Drug Therapy, Combination , Female , Isothiocyanates/administration & dosage , Mice , Serotonin/metabolism , Sulfoxides , Tumor Burden/drug effects , Tumor Stem Cell Assay , Xenograft Model Antitumor Assays
11.
Cancers (Basel) ; 15(13)2023 Jul 02.
Article in English | MEDLINE | ID: mdl-37444578

ABSTRACT

Various cancer cell-associated intrinsic and extrinsic inputs act on YAP/TAZ proteins to mediate the hyperactivation of the TEAD transcription factor-based transcriptome. This YAP/TAZ-TEAD activity can override the growth-limiting Hippo tumor-suppressor pathway that maintains normal tissue homeostasis. Herein, we provide an integrated summary of the contrasting roles of YAP/TAZ during normal tissue homeostasis versus tumor initiation and progression. In addition to upstream factors that regulate YAP/TAZ in the TME, critical insights on the emerging functions of YAP/TAZ in immune suppression and abnormal vasculature development during tumorigenesis are illustrated. Lastly, we discuss the current methods that intervene with the YAP/TAZ-TEAD oncogenic signaling pathway and the emerging applications of combination therapies, gut microbiota, and epigenetic plasticity that could potentiate the efficacy of chemo/immunotherapy as improved cancer therapeutic strategies.

12.
Pediatr Blood Cancer ; 58(2): 181-4, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21319292

ABSTRACT

BACKGROUND: Circulating endothelial cells (CECs) have been detected at increased numbers in patients with solid cancers. CECs have not been systematically evaluated in patients with osteosarcoma. PROCEDURE: Patients 12 months to 30 years of age with newly diagnosed high-grade osteosarcoma were eligible for this prospective cohort study. Patients provided a single blood sample at study entry for CEC quantification by flow cytometry at a single reference laboratory. CECs were defined as CD146+, CD31+, CD45-, and CD133-. CEC progenitor cells (CEPs) were defined as CD146+, CD31+, CD45-, and CD133+. RESULTS: Eighteen patients enrolled (11 males; median age 16 years; range 5-21 years). CEC counts did not differ between patients with osteosarcoma compared to seven pediatric healthy controls (median 645 cells/ml, range 60-5,320 cells/ml vs. 1,670 cells/ml, range 330-4,700 cells/ml, respectively; P = 0.12). CEP counts did not differ between patients compared to controls (median 126 cells/ml, range 0-5,320 cells/ml vs. median 260 cells/ml, range 0-10,670 cells/ml, respectively; P = 0.69). CEC and CEP counts did not correlate with metastatic status, tumor size, or histologic response to neoadjuvant chemotherapy. CONCLUSIONS: CEC and CEP levels are not increased in patients with osteosarcoma compared to healthy controls. CECs and CEPs do not correlate with clinical features of osteosarcoma. Alternative novel markers of disease burden and response are needed in this disease.


Subject(s)
Biomarkers, Tumor/blood , Bone Neoplasms/pathology , Endothelial Cells/pathology , Neoplastic Cells, Circulating/pathology , Osteosarcoma/pathology , Stem Cells/pathology , Adolescent , Adult , Antigens, CD/blood , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bone Neoplasms/blood , Bone Neoplasms/drug therapy , Case-Control Studies , Child , Child, Preschool , Cohort Studies , Endothelial Cells/metabolism , Female , Flow Cytometry , Follow-Up Studies , Humans , Male , Neoadjuvant Therapy , Neoplasm Metastasis , Neoplastic Cells, Circulating/metabolism , Osteosarcoma/blood , Osteosarcoma/drug therapy , Prognosis , Prospective Studies , Stem Cells/metabolism , Young Adult
13.
Cancers (Basel) ; 14(6)2022 Mar 08.
Article in English | MEDLINE | ID: mdl-35326525

ABSTRACT

Resistance to chemotherapeutics and high metastatic rates contribute to the abysmal survival rate in patients with pancreatic cancer. An alternate approach for treating human pancreatic cancer involves repurposing the anti-inflammatory drug, aspirin (ASA), with oseltamivir phosphate (OP) in combination with the standard chemotherapeutic agent, gemcitabine (GEM). The question is whether treatment with ASA and OP can sensitize cancer cells to the cytotoxicity induced by GEM and limit the development of chemoresistance. To assess the key survival pathways critical for pancreatic cancer progression, we used the AlamarBlue cytotoxicity assay to determine the cell viability and combination index for the drug combinations, flow cytometric analysis of annexin V apoptosis assay to detect apoptotic and necrotic cells, fluorometric QCM™ chemotaxis migration assay to assess cellular migration, fluorometric extracellular matrix (ECM) cell adhesion array kit to assess the expression of the ECM proteins, scratch wound assay using the 96-well WoundMaker™, and the methylcellulose clonogenic assay to assess clonogenic potential. The combination of ASA and OP with GEM significantly upended MiaPaCa-2 and PANC-1 pancreatic cancer cell viability, clonogenic potential, expression of critical extracellular matrix proteins, migration, and promoted apoptosis. ASA in combination with OP significantly improves the effectiveness of GEM in the treatment of pancreatic cancer and disables key survival pathways critical to disease progression.

14.
Cancers (Basel) ; 14(15)2022 Jul 23.
Article in English | MEDLINE | ID: mdl-35892853

ABSTRACT

Metastatic pancreatic cancer has an invariably fatal outcome, with an estimated median progression-free survival of approximately six months employing our best combination chemotherapeutic regimens. Once drug resistance develops, manifested by increased primary tumor size and new and growing metastases, patients often die rapidly from their disease. Emerging evidence indicates that chemotherapy may contribute to the development of drug resistance through the upregulation of epithelial-mesenchymal transition (EMT) pathways and subsequent cancer stem cell (CSC) enrichment. Neuraminidase-1 (Neu-1) regulates the activation of several receptor tyrosine kinases implicated in EMT induction, angiogenesis, and cellular proliferation. Here, continuous therapeutic targeting of Neu-1 using parenteral perfusion of oseltamivir phosphate (OP) and aspirin (ASA) with gemcitabine (GEM) treatment significantly disrupts tumor progression, critical compensatory signaling mechanisms, EMT program, CSC, and metastases in a preclinical mouse model of human pancreatic cancer. ASA- and OP-treated xenotumors significantly inhibited the metastatic potential when transferred into animals.

16.
Front Immunol ; 13: 933329, 2022.
Article in English | MEDLINE | ID: mdl-36248858

ABSTRACT

Tumor hypoxia and oxidative stress reprograms cancer stem cells (CSCs) to a highly aggressive and inflammatory phenotypic state of tumor stemness. Previously, we characterized tumor stemness phenotype in the ATP Binding Cassette Subfamily G Member 2 (ABCG2)-positive migratory side population (SPm) fraction of CSCs exposed to extreme hypoxia followed by reoxygenation. Here, we report that post-hypoxia/reoxygenation SPm+/ABCG2+ CSCs exerts defense against pathogen invasion that involves bystander apoptosis of non-infected CSCs. In an in vitro assay of cancer cell infection by Bacillus Calmette Guerin (BCG) or mutant Mycobacterium tuberculosis (Mtb) strain 18b (Mtb-m18b), the pathogens preferentially replicated intracellular to SPm+/ABCG2+ CSCs of seven cell lines of diverse cancer types including SCC-25 oral squamous cancer cell line. The conditioned media (CM) of infected CSCs exhibited direct anti-microbial activity against Mtb and BCG, suggesting niche defense against pathogen. Importantly, the CM of infected CSCs exhibited marked in vitro bystander apoptosis toward non-infected CSCs. Moreover, the CM-treated xenograft bearing mice showed 10- to 15-fold reduction (p < 0.001; n = 7) in the number of CSCs residing in the hypoxic niches. Our in vitro studies indicated that BCG-infected SPm+/ABCG2+ equivalent EPCAM+/ABCG2+ CSCs of SCC-25 cells underwent pyroptosis and released a high mobility group box protein 1 (HMGB1)/p53 death signal into the tumor microenvironment (TME). The death signal can induce a Toll-like receptor 2/4-mediated bystander apoptosis in non-infected CSCs by activating p53/MDM2 oscillation and subsequent activation of capase-3-dependent intrinsic apoptosis. Notably, SPm+/ABCG2+ but not SP cells undergoing bystander apoptosis amplified the death signal by further release of HMGB1/p53 complex into the TME. These results suggest that post-hypoxia SPm+/ABCG2+ CSCs serve a functional role as a tumor stemness defense (TSD) phenotype to protect TME against bacterial invasion. Importantly, the CM of TSD phenotype undergoing bystander apoptosis may have therapeutic uses against CSCs residing in the hypoxic niche.


Subject(s)
HMGB1 Protein , Stem Cell Niche , Adenosine Triphosphate , Animals , BCG Vaccine , Cell Line, Tumor , Culture Media, Conditioned , Epithelial Cell Adhesion Molecule , Humans , Hypoxia , Mice , Neoplastic Stem Cells , Toll-Like Receptor 2 , Tumor Suppressor Protein p53
17.
Cancers (Basel) ; 13(11)2021 Jun 03.
Article in English | MEDLINE | ID: mdl-34205080

ABSTRACT

Therapeutic targeting of stem cells needs to be strategically developed to control tumor growth and prevent metastatic burden successfully. Breast cancer presents a unique clinical problem because of the variety of cellular subtypes present, including cancer stem cells (CSCs). The development of 3D stem-like properties of human breast tumor spheroids in stem cell factor conditioned media was investigated in orthotopic xenografts for enhanced tumorgenicity in the athymic nude rat model. MCF-7, ZR-75-1, and MDA-MB-231 breast cancer cell lines were cultured in serum-free, stem cell factor-supplemented medium under non-adherent conditions and passaged to generate 3rd generation spheroids. The spheroids were co-cultured with fetal lung fibroblast (FLF) cells before orthotopic heterotransplantation into the mammary fat pads of athymic nude rats. Excised xenografts were assessed histologically by H&E staining and immunohistochemistry for breast cancer marker (ERB1), proliferation marker (Ki67), mitotic marker (pHH3), hypoxia marker (HIF-2α), CSC markers (CD47, CD44, CD24, and CD133), and vascularization markers (CD31, CD34). Breast cancer cells cultured in stem cell factor supplemented medium generated 3D spheroids exhibited increased stem-like characteristics. The 3D stem-like spheroids co-cultured with FLF as supporting stroma reproducibly and efficiently established orthotopic breast cancer xenografts in the athymic nude rat.

18.
Oncotarget ; 12(15): 1470-1489, 2021 Jul 20.
Article in English | MEDLINE | ID: mdl-34316328

ABSTRACT

OBJECTIVE: Aberrations in the PI3K/AKT/mTOR survival pathway in many cancers are the most common genomic abnormalities. The phytochemical and bioactive agent sulforaphane (SFN) has nutrigenomic potential in activating the expression of several cellular protective genes via the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2). Nrf2 is primarily related to mechanisms of endogenous cellular defense and survival. The efficacy of SFN in combination with acetazolamide (AZ) was investigated in reducing typical H727 and atypical H720 BC survival, migration potential, and apoptosis in vitro and in vivo preclinical xenograft tissues. MATERIALS AND METHODS: Microscopic imaging, immunocytochemistry, wound healing assay, caspase-cleaved cytokeratin 18 (M30, CCK18) CytoDeath ELISA assay, immunofluorescence labeling assays for apoptosis, hypoxia, Western Blotting, Tunnel assay, measurement of 5-HT secretion by carbon fiber amperometry assay, quantitative methylation-specific PCR (qMSP), morphologic changes, cell viability, apoptosis activity and the expression levels of phospho-Akt1, Akt1, HIF-1α, PI3K, p21, CAIX, 5-HT, phospho-mTOR, and mTOR in xenografts derived from typical H727 and atypical H720 BC cell lines. RESULTS: Combining AZ+SFN reduced tumor cell survival compared to each agent alone, both in vitro and in vivo xenograft tissues. AZ+SFN targeted multiple pathways involved in cell cycle, serotonin secretion, survival, and growth pathways, highlighting its therapeutic approach. Both H727 and H720 cells were associated with induction of apoptosis, upregulation of the p21 cell cycle inhibitor, and downregulation of the PI3K/Akt/mTOR pathway, suggesting that the PI3K/Akt/mTOR pathway is a primary target of the AZ+SFN combination therapy. CONCLUSIONS: Combining SFN+AZ significantly inhibits the PI3K/Akt/mTOR pathway and significantly reducing 5-HT secretion in carcinoid syndrome.

19.
Cancers (Basel) ; 13(14)2021 Jul 18.
Article in English | MEDLINE | ID: mdl-34298809

ABSTRACT

Cancer immunotherapy harnesses the immune system by targeting tumor cells that express antigens recognized by immune system cells, thus leading to tumor rejection. These tumor-associated antigens include tumor-specific shared antigens, differentiation antigens, protein products of mutated genes and rearrangements unique to tumor cells, overexpressed tissue-specific antigens, and exogenous viral proteins. However, the development of effective therapeutic approaches has proven difficult, mainly because these tumor antigens are shielded, and cells primarily express self-derived antigens. Despite innovative and notable advances in immunotherapy, challenges associated with variable patient response rates and efficacy on select tumors minimize the overall effectiveness of immunotherapy. Variations observed in response rates to immunotherapy are due to multiple factors, including adaptative resistance, competency, and a diversity of individual immune systems, including cancer stem cells in the tumor microenvironment, composition of the gut microbiota, and broad limitations of current immunotherapeutic approaches. New approaches are positioned to improve the immune response and increase the efficacy of immunotherapies, highlighting the challenges that the current global COVID-19 pandemic places on the present state of immunotherapy.

20.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 7): m703, 2009 Jun 06.
Article in English | MEDLINE | ID: mdl-21582649

ABSTRACT

In the title complex, [Ni(C(21)H(24)N(2)O(4))], the Ni(II) ion has a slightly distorted square-planar geometry, coordinated by the two N and two O atoms of a new tetra-dentate Schiff base ligand. The dihedral angle between the planes of the two NiNC(3)O chelate rings is 14.37 (12)°.

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