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Although chemotherapy with magnetic nanocarriers has witnessed significant advancement in the field of cancer treatment, multimodal diagnosis and combinatorial therapy using a single nanoplatform will have much better efficacy in achieving superior results. Herein, we constructed a smart theranostic system by combining pH-sensitive tartaric acid-stabilized Fe 3 O 4 magnetic nanocarriers (TMNCs) with SPECT imaging and a chemotherapeutic agent for image-guided chemo-hyperthermia therapy. The carboxyl-enriched exteriors of TMNCs provided sites for the conjugation of a chemotherapeutic drug (doxorubicin hydrochloride, DOX) and radiolabeling ( 141 Ce). The usage of 145.4 keV gamma rays made this platform an ideal choice for in vivo SPECT-CT imaging, showing the retention of the nanoformulation in the tumor site even after 28 days. Further, TMNCs showed a very high transverse relaxation rate ( r 2 ) of 171 mM -1 s -1 , which is higher than that of clinically approved magnetic resonance imaging (MRI) contrast agents such as ferumoxtran (65 mM -1 s -1 ) and ferumoxides (120 mM -1 s -1 ). Further, the developed drug-loaded hybrid platform showed significantly higher cytotoxicity towards breast cancer cells, which was augmented by in vitro magnetic hyperthermia. Bright-field microscopy and cell cycle analysis suggested that cell death occurred through induction of G2-M arrest and subsequent apoptosis. These findings clearly suggest the potential of the developed hybrid nanoplatform for image-guided combination therapy.

Thorium-232 (Th-232) is a promising fuel for advanced nuclear reactors. However, in case of internal human exposure to Th, there is currently no effective modality for its removal from liver and skeleton or for mitigating its effect. The FDA-approved agent, diethylenetriaminepentaacetate (DTPA), can remove Th and other actinides from blood circulation only. For the first time, a rationally-selected polyherbal hepatoprotective i.e. Liv52® (L52S), was evaluated in-combination with DTPA for its Th decorporation ability in Swiss mice. Inductively-coupled plasma mass spectroscopic analysis showed that oral administration of L52S in conjunction with DTPA significantly decreased Th burden from liver (20 %) and skeleton (33 %) as well as enhanced Th excretion (∼2.5 folds) through urine in comparison to DTPA or L52S alone. The combinatorial therapy was found to be complementary in-action, ameliorating Th-induced tissue damage in liver, spleen, and bone more effectively than monotherapy. Furthermore, markers of liver function (alanine transaminase) and liver inflammation and fibrosis (NF-κB & keratin) further validated the beneficial effect of L52S. The human consumption of L52S for various liver disorders further supports its clinical application for Th decorporation and mitigation of its health effects., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Tumor-associated macrophages (TAMs) secrete cytokines, chemokines, and growth factors in the tumor microenvironment (TME) to support cancer progression. Higher TAM infiltration in the breast TME is associated with a poor prognosis. Previous studies have demonstrated the role of macrophages in stimulating long-range intercellular bridges referred to as tunneling nanotubes (TNTs) in cancer cells. Intercellular communication between cancer cells via TNTs promotes cancer growth, invasion, metastasis, and therapy resistance. Given the important role of TNTs and macrophages in cancer, the role of macrophage-induced TNTs in chemotherapy drug doxorubicin resistance is not known. Furthermore, the mechanism of macrophage-mediated TNT formation is elusive. In this study, it is shown that the macrophage-conditioned medium (MΦCM) partially mimicked inflammatory TME, induced an EMT phenotype, and increased migration in MCF-7 breast cancer cells. Additionally, secreted proteins in MΦCM induced TNT formation in MCF-7 cells, which led to increased resistance to doxorubicin. Transcriptomic analysis of MΦCM-treated MCF-7 cells showed enrichment of the NF-κB and focal adhesion pathways, as well as upregulation of genes involved in EMT, extracellular remodeling, and actin cytoskeleton reorganization. Interestingly, inhibitors of PKC, Src, NF-κB, and p38 decreased macrophage-induced TNT formation in MCF-7 cells. These results reveal the novel role of PKC and Src in inducing TNT formation in cancer cells and suggest that inhibition of PKC and Src activity may likely contribute to reduced macrophage-breast cancer cell interaction and the potential therapeutic strategy of cancer., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Inc.)

Thorium-232 (Th), the most abundant naturally occurring nuclear fuel, has been identified as a sustainable source of energy. In view of its large-scale utilization and human evidence of lung disorders and carcinogenicity, it is imperative to understand the effect of Th exposure on lung cells. The present study investigated the effect of Th-dioxide (1-100 μg/mL, 24-48 h) on expression of surfactant proteins (SPs) (SP-A, SP-B, SP-C, and SP-D, which are essential to maintain lung's surface tension and host-defense) in human lung cells (WI26 and A549), representative of alveolar cell type-I and type-II, respectively. Results demonstrated the inhibitory effect of Th on transcriptional expression of SP-A, SP-B, and SP-C. However, Th promoted the mRNA expression of SP-D in A549 and reduced its expression in WI26. To a significant extent, the effect of Th on SPs was found to be in accordance with their protein levels. Moreover, Th exposure altered the extracellular release of SP-D/A from A549, which remained unaltered in WI26. Our results suggested the differential role of oxidative stress and ATM and HSP90 signaling in Th-induced alterations of SPs. These effects of Th were found to be consistent in lung tissues of mice exposed to Th aerosols, suggesting a potential role of SPs in Th-associated lung disorders.

Triple negative breast carcinoma (TNBC) accounts for 15-20 % of all incident breast cancers (BC) and is known to be highly invasive, has fewer treatment options, and tends to have a worse prognosis. However, due to its biological heterogeneity and diverse clinical and epidemiological behaviors, TNBC lacks a tumor-specific targeted therapy. In the present work we have developed a TNBC-specific targeted nano-delivery agent comprising of a cRGD labeled magneto-liposome (T-LMD) co-encapsulated with oleic acid coated iron oxide nanoparticles (MN-OA) and doxorubicin (Dox) in the liposome bilayer and core, respectively. T-LMD was found to show enhanced uptake and induction of ferroptotic cell death in MDA-MB-231, a TNBC model cell line. Additionally, T-LMD induced ferroptosis was found to be accompanied by release of HMGB1, an immunogenic cell death marker, suggesting its immunogenicity for augmenting the activation of anti-tumor immunity in TNBC. The strategic placement of IONPs in the liposome bilayer of T-LMD facilitates the sensitization of MDA-MB-231 cells to undergo ferroptosis; predominantly via the activation of the iron/lipid metabolism pathway, as validated by use of small molecule ferroptosis inhibitor (ferrostatin-1) and iron chelator (deferoxamine). Activation of ferroptotic cell death was also corroborated by ferroptosis specific-ultrastructural alterations in the shape/size of cellular mitochondria and cell ballooning as observed by transmission electron microscopy and bright field imaging, respectively. Thus, our ferroptosis nano-inducer (T-LMD) can efficiently kill TNBC cells via enhanced LPO and ROS generation leading to membrane damage and consequent release of LDH and HMGB1, induce mitochondrial alterations and enhanced DNA double strand breaks. Altogether, our results suggest significant implications of T-LMD for treatment of TNBC., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Thorium-232 (Th-232), a naturally-occurring radioactive element with high potential of nuclear fuel is now being utilized in advanced nuclear reactors for CO 2 -free energy generation. To achieve all-round capability in Th-fuel cycle for health and environment, understanding the biological effects of Th-232 at cellular and molecular level are extremely important. The present study investigated long-term effects (6 and 12 months) of Th-232 (4, 10 and 20 mg/kg) on gene expression in mice liver (major target organ). Analysis of differentially expressed genes (DEGs, ≥2.0 folds, p < 0.05) showed that with the increase of Th dose (4 to 20 mg/kg), the number of upregulated DEGs increased and the number of downregulated DEGs decreased significantly. A significant number of upregulated DEGs (10 genes in 6 months and 14 genes in 12 months) were found common between 4 and 20 mg/kg. Gene Ontology analysis revealed significant (P adj  ~ 10 -6 -10 -28 ) enrichment of upregulated DEGs for metabolic process, signal transduction, cell death, cell cycle and cell proliferation. KEGG pathway analysis showed DEGs significantly enriched in several cancer-related pathways including hepatocellular carcinoma (HCC). Protein-protein interaction analysis further revealed statistically significant functional interaction (p-value ~10-6-10-10) among the proteins of HCC, which identified β-catenin as one of the most significant signaling nodes in association with myc, an oncogene and p53, a tumor suppressor. Importantly, these results were corroborated by quantitative real time-polymerase chain reaction and western blotting in liver tissues of animals exposed to Th-232. This study insights Wnt/β-catenin signaling network attributable to drive Th-induced liver carcinogenesis, which may have significant implications for management of long-term effects of Th-232., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Tumor associated macrophages (TAMs) are one of the most prominent immune cells in the breast tumor microenvironment (TME). TAMs are categorised into classically activated anti-tumorigenic M1 and alternatively activated pro-tumorigenic M2 macrophages. TAMs are known to promote cancer pathogenesis by facilitating cancer cell and cancer stem cell growth, angiogenesis, immune evasion, invasion, and migration. Consequently, TAMs drive cancer progression towards metastasis. This chapter describes the role of TME in driving monocyte recruitment and polarization toward the M2 phenotype. We also illustrate the modalities of intercellular networking such as paracrine signaling, exosomes, and tunneling nanotubes (TNTs) that TAMs and cancer cells employ within TME to communicate with each other and with other cells of TME to facilitate the dynamic process of cancer progression. Finally, we discuss the clinical implications of TAMs in breast cancer and potential therapeutic strategies targeting TAM recruitment, polarization, and TAM-mediated immune evasion for effective cancer therapy., (© 2024. The Author(s), under exclusive license to Springer Nature Switzerland AG.)

The present pilot study aims to investigate the diagnostic and prognostic efficacy of serum HSP90 beta in Head and Neck Squamous Cell Carcinoma (HNSCC) patients subjected to localized hyperthermia therapy (HT). Serum levels of HSP90 beta were measured by ELISA and its diagnostic and prognostic efficacy was determined by receiver operating characteristic curve (ROC) analysis. HNSCC patients showed significantly (P<0.05) higher serum levels of HSP90 beta (65.6±13.08 ng/ml) compared to Healthy Controls (HC: 23.5±3.8 ng/ml). No significant difference was observed in serum HSP90 beta levels between complete responders (CR) and non-responders (NR) in the chemo-radiation therapy (CRT) cohort. However, in CRT+HT cohort, CR showed significantly (P = 0.02) lower serum HSP90 beta levels at 24 h after HT (25.6±9.04 ng/ml) compared to NR (130.5±34.2 ng/ml). Youden's index values between HNSCC versus HC, CR versus NR (CRT) and CR versus NR (CRT+HT) were found to be 0.47, 0.45 and 0.80, respectively. Thus, alterations in the serum HSP90 beta after HT suggest its potential in prognosis of HT response in HNSCC patients. Elevated levels of HSP90 beta may serve as a promising diagnostic serum bio-marker for HNSCC. However, further validation in larger patient samples is needed for clinical translation of HSP90 beta as diagnostic and prognostic biomarker., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Shetake et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Tunneling nanotubes (TNTs) are intercellular conduits which meet the communication needs of non-adjacent cells situated in the same tissue but at distances up to a few hundred microns. TNTs are unique type of membrane protrusion which contain F-actin and freely hover over substratum in the extracellular space to connect the distant cells. TNTs, known to form through actin remodeling mechanisms, are intercellular bridges that connect cytoplasm of two cells, and facilitate the transfer of organelles, molecules, and pathogens among the cells. In tumor microenvironment, TNTs act as communication channel among cancer, normal, and immune cells to facilitate the transfer of calcium waves, mitochondria, lysosomes, and proteins, which in turn contribute to the survival, metastasis, and chemo-resistance in cancer cells. Recently, TNTs were shown to mediate the transfer of nanoparticles, drugs, and viruses between cells, suggesting that TNTs could be exploited as a potential route for delivery of anti-cancer agents and oncolytic viruses to the target cells. The present review discusses the emerging concepts and role of TNTs in the context of chemo- and radio-resistance with implications in the cancer therapy., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Noninvasive imaging techniques for the early detection of infections are in high demand. In this study, we present the development of an infection imaging agent consisting of the antimicrobial peptide fragment UBI (31-38) conjugated to the chelator 1,4,7-triazacyclononane,1-glutaric acid-4,7-acetic acid (NODAGA), which allows for labeling with the positron emitter Ga-68. The preclinical evaluation of [ 68 Ga]Ga-NODAGA-UBI (31-38) was conducted to investigate its potential for imaging bacterial infections caused by Staphylococcus aureus. The octapeptide derived from ubiquicidin, UBI (31-38), was synthesized and conjugated with the chelator NODAGA. The conjugate was then radiolabeled with Ga-68. The radiolabeling process and the stability of the radio formulation were confirmed through chromatography. The study included both in vitro evaluations using S. aureus and in vivo evaluations in an animal model of infection and inflammation. Positron emission tomography (PET) and Cherenkov luminescence imaging (CLI) were performed to visualize the targeted localization of the radio formulation at the site of infection. Ex vivo biodistribution studies were carried out to quantify the uptake of the radio formulation in different organs and tissues. Additionally, the uptake of [ 18 F]Fluorodeoxyglucose ([ 18 F] FDG) in the animal model was also studied for comparison. The [ 68 Ga]Ga-NODAGA-UBI (31-38) complex consistently exhibited high radiochemical purity (>90%) after formulation. The complex demonstrated stability in saline, phosphate-buffered saline, and human serum for up to 3 h. Notably, the complex displayed significantly higher uptake in S. aureus, which was inhibited in the presence of unconjugated UBI (29-41) peptide, confirming the specificity of the formulation for bacterial membranes. Bacterial imaging capability was also observed in PET and CLI images. Biodistribution results indicated a substantial target-to-nontarget ratio of approximately 4 at 1 h postinjection of the radio formulation. Conversely, the uptake of [ 18 F]FDG in the animal model did not allow for the discrimination of infected and inflamed sites. Our studies have demonstrated that [ 68 Ga]Ga-NODAGA-UBI (31-38) holds promise as a radiotracer for imaging bacterial infections caused by S. aureus., (© 2023 Wiley Periodicals LLC.)

Deoxyglucose conjugated nanoparticles with persistent luminescence have shown theragnostic potential. In this study, deoxyglucose-conjugated nano-particles with persistent luminescence properties were synthesized, and their theragnostic potential was evaluated in fibrosarcoma cancer cells and a tumor model. The uptake of nano-formulation was found to be higher in mouse fibrosarcoma (WEHI-164) cells cultured in a medium without glucose. Nanoparticles showed a higher killing ability for cancer cells compared to normal cells. A significant accumulation of nanoparticles to the tumor site in mice was evident by the increased tumor/normal leg ratio, resulting in a significant decrease in tumor volume and weight. Histopathological studies showed a significant decrease in the number of dividing mitotic cells but a greater number of apoptotic/necrotic cells in nanoparticle-treated tumor tissues, which was correlated with a lower magnitude of Ki-67 expression (a proliferation marker). Consequently, our results showed the potential of our nano-formulation for cancer theragnosis., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Purpose: The assumption that traversal of the cell nucleus by ionizing radiation is a prerequisite to induce genetic damage, or other important biological responses, has been challenged by studies showing that oxidative alterations extend beyond the irradiated cells and occur also in neighboring bystander cells. Cells and tissues outside the radiation field experience significant biochemical and phenotypic changes that are often similar to those observed in the irradiated cells and tissues. With relevance to the assessment of long-term health risks of occupational, environmental and clinical exposures, measurable genetic, epigenetic, and metabolic changes have been also detected in the progeny of bystander cells. How the oxidative damage spreads from the irradiated cells to their neighboring bystander cells has been under intense investigation. Following a brief summary of the trends in radiobiology leading to this paradigm shift in the field, we review key findings of bystander effects induced by low and high doses of various types of radiation that differ in their biophysical characteristics. While notable mechanistic insights continue to emerge, here the focus is on the many means of intercellular communication that mediate these effects, namely junctional channels, secreted molecules and extracellular vesicles, and immune pathways., Conclusions: The insights gained by studying radiation bystander effects are leading to a basic understanding of the intercellular communications that occur under mild and severe oxidative stress in both normal and cancerous tissues. Understanding the mechanisms underlying these communications will likely contribute to reducing the uncertainty of predicting adverse health effects following exposure to low dose/low fluence ionizing radiation, guide novel interventions that mitigate adverse out-of-field effects, and contribute to better outcomes of radiotherapeutic treatments of cancer. In this review, we highlight novel routes of intercellular communication for investigation, and raise the rationale for reconsidering classification of bystander responses, abscopal effects, and expression of genomic instability as non-targeted effects of radiation.

The chemo-therapeutic efficacy of Doxorubicin (Dox), a potent anti-cancer drug used in the treatment of several solid tumors, is severely compromised by its cardio-toxicity. To overcome this shortcoming and exploit the utmost theranostic potential of nano-formulations, magnetic nanoparticles co-encapsulated with Dox and indocyanine green (ICG) in a liposomal carrier and tagged with cyclic RGD peptide were rationally designed and synthesized. These magneto-liposomes (T-LMD) showed αvβ3-integrin receptor targeting and higher cyto-toxicity in several cancer cell lines (i.e. lung, breast, skin, brain and liver cancer) in combination with or without gamma radiation or magnetic hyperthermia therapy as compared to clinical liposomal nano-formulation of Dox (Lippod™). Mechanism of chemo-radio-sensitization was found to involve activation of JNK mediated pro-apoptotic signaling axis and delayed repair of DNA double strand breaks. Real time imaging of ICG labeled T-LMD suggested ~6-18 fold higher tumor accumulation of T-LMD as compared to off-target organs (kidney, liver, spleen, intestine, lungs and heart) and resulted in its higher combinatorial (chemo-radio-hyperthermia) tumor therapy efficacy as compared to Lippod™. Moreover, T-LMD showed insignificant toxicity to the heart tissue as suggested by serum levels of CK-MB, histo-pathological analysis, anti-oxidant enzyme activities (Catalase and GST) and markers of cardiac fibrosis, suggesting its potential for targeted multi-modal therapy of cancer., Competing Interests: Declaration of competing interest Authors declare no competing interests., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Hepatic disorders reported in humans exposed to Thorium-232 (Th-232) rationalizes the present study investigating the toxicological response of normal human liver cells (WRL 68) and its validation in Swiss mice. Cell count analysis of WRL 68 cells-treated with Th-nitrate (1-200 μM) estimated IC50 of ∼24 μM (at 24 h) and 35 μM (at 48 h). Analysis of cell viability (trypan blue assay) showed the IC50 of ∼172 μM. Phase contrast bright-field microscopy revealed Th-induced morphological changes and cell-released microvesicle-like structures in extracellular space. Th-estimation by ICP-MS (Inductively-coupled plasma mass-spectrometry) showed uptake of Th by cells as a function of concentration and incubation time. Employing DTPA as a chelating agent in cell harvesting solution, cell-internalized/strongly-bound Th was estimated to be ∼42% of total incubated Th. Th-uptake studies in the presence of ion-channel specific inhibitors (e.g. nifedipine, thapsigargin) revealed the role of plasma membrane calcium channels and cytoplasmic calcium in modulating the Th-uptake. Transmission electron microscopy of Th-treated cells showed cell-derived extracellular vesicles, alterations in the shape and size of nucleus and mitochondria as well as cytoplasmic inclusions. The order of Th accumulation in various sub-cellular protein fractions was found to be as cytoskeleton (43%) > cytoplasmic (15%) > chromatin (7%) > nuclear (5%) & membrane (5%). Immunofluorescence analysis of WRL 68 cells showed that Th significantly altered the expression of cytoskeleton proteins (F-actin and keratin), which was further validated in liver tissues of Swiss mice administered with Th-232. Findings herein highlight the role of calcium channels and cytoskeleton in Th-induced toxicity. Keywords: Thorium toxicity; Liver cells; Calcium channels; Sub-cellular targets, Cytoskeleton; Swiss Mice., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The bioreductive enzymes typically upregulated in hypoxic tumor cells can be targeted for developing diagnostic and drug delivery applications. In this study, a new fluorescent probe 4-(6-nitro-1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl)benzaldehyde (NIB) based on a nitronaphthalimide skeleton that could respond to nitroreductase (NTR) overexpressed in hypoxic tumors is designed and its application in imaging tumor hypoxia is demonstrated. The docking studies revealed favourable interactions of NIB with the binding pocket of NTR-Escherichia coli. NIB, which is synthesized through a simple and single step imidation of 4-nitro-1,8-naphthalic anhydride displayed excellent reducible capacity under hypoxic conditions as evidenced from cyclic voltammetry investigations. The fluorescence measurements confirmed the formation of identical products (NIB-red) during chemical as well as NTR-aided enzymatic reduction in the presence of NADH. The potential fluorescence imaging of hypoxia based on NTR-mediated reduction of NIB is confirmed using in-vitro cell culture experiments using human breast cancer (MCF-7) cells, which displayed a significant change in the fluorescence colour and intensity at low NIB concentration within a short incubation period in hypoxic conditions., (© 2021. The Author(s).)

Inhalation represents the most prevalent route of exposure with Thorium-232 compounds (Th-nitrate/Th-dioxide)/Th-containing dust in real occupational scenario. The present study investigated the mechanism of Th response in normal human alveolar epithelial cells (WI26), exposed to Th-nitrate or colloidal Th-dioxide (1-100 μg/ml, 24-72 h). Assessment in terms of changes in cell morphology, cell proliferation (cell count), plasma membrane integrity (lactate dehydrogenase leakage) and mitochondrial metabolic activity (MTT reduction) showed that Th-dioxide was quantitatively more deleterious than Th-nitrate to WI26 cells. TEM and immunofluorescence analysis suggested that Th-dioxide followed a clathrin/caveolin-mediated endocytosis, however, membrane perforation/non-endocytosis seemed to be the mode of Th internalization in cells exposed to Th-nitrate. Th-estimation by ICP-MS showed significantly higher uptake of Th in cells treated with Th-dioxide than with Th-nitrate at a given concentration. Both Th-dioxide and nitrate were found to increase the level of reactive oxygen species, which seemed to be responsible for lipid peroxidation, alteration in mitochondrial membrane potential and DNA-damage. Amongst HSPs, the protein levels of HSP70 and HSP90 were affected differentially by Th-nitrate/dioxide. Specific inhibitors of ATM (KU55933) or HSP90 (17AAG) were found to increase the Th- cytotoxicity suggesting prosurvival role of these signaling molecules in rescuing the cells from Th-toxicity., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Microplasts are large extracellular vesicles originating from migratory, invasive, and metastatic cancer cells. Here, to gain insight into the role of microplasts in cancer progression, we performed a proteomic and transcriptomic characterization of microplasts isolated from MCF-7 breast cancer cells treated with macrophage-conditioned medium. These cells were found to be viable, highly migratory, and metabolically active, indicating that microplasts derived from these cells are not apoptotic bodies. Transcriptomic/proteomic analyses identified 10273 mRNAs and 821 proteins in microplasts. Interestingly, 377 microplast mRNAs coded for corresponding microplast proteins. Microplast mRNAs and proteins were mainly associated with binding and catalytic activities. Microplasts showed enrichment of mRNAs involved in transcription regulation and proteins involved in processes such as cell-cell adhesion and translation. Pathway analysis showed enrichment of ribosomes and carbon metabolism. These results suggest a close resemblance between microplasts and parent cells, with mRNA and protein cargo relevant in intercellular signaling., (© 2021 Federation of European Biochemical Societies.)

Purpose: High LET including alpha radiation-based approaches have been proved as a promising mode for cancer therapy owing to their biophysical and radiobiological advantages compared to photon beams. Studies pertaining to effect of α-radiation on cancer cells are limited to cytotoxic high doses., Materials and Methods: In this study, human lung adenocarcinoma (A549) cells were α-irradiated using 241 Am α-irradiator and effects of low dose of alpha radiation on these cells was studied under in vitro and in vivo conditions., Results: Clonogenic and other assays showed increased cellular proliferation at lower doses (1.36 and 6.8 cGy) but killing at higher doses (13.6-54.4 cGy). Further studies at low dose of alpha (1.36 cGy) showed increased TGF-β1 in the conditioned medium (CM) at early time point (24 h) but CM replacement did not affect the clonogenic survival. In these cells, increased phosphorylation of connexin 43 was correlated with decrease in gap-junction communication observed by dye transfer co-culture experiment. A decrease in caveolin-1 but increase in survivin expression was observed in low dose α-irradiated cells. An increase in cyclinD1 and decrease in Bcl-2, the target proteins of survivin, was observed in these cells. Low dose α-irradiated cancer cells transplanted in SCID mice showed significantly higher tumor volume, which was accompanied with an increased fraction of mitotic and PCNA/Ki67 positive cells in these tumor tissues., Conclusions: Taken together, our results suggest an increase in proliferation and tumor volume at in vitro and in vivo levels, respectively, when A549 cells were irradiated with low dose of α-radiation. These findings may be relevant for a better understanding of radiobiological processes during high LET-based cancer radiotherapy.

At the diagnostic stage, metastasis detection is around 75% in the lung cancer patients. Major clinical challenge faced by medical oncologists is the unpredictable metastasis development in non-metastatic patients. The literature regarding the biomarkers/factors prognosticating metastasis in non-metastatic patients during follow-up is very limited. In this pilot study, the levels of serum biomarkers (IL-8, VEGF, MMP-2, MMP-9) were measured at diagnosis stage of non-metastatic lung cancer patients and these observations were evaluated for metastasis development after follow-up of median 29.2 months. After follow-up, ∼40% of these patients developed metastasis. The average age of non-metastatic patients which later developed metastasis, was found to be lower than the patients continued to be non-metastatic. These patients also showed higher levels of IL-8 and MMP-9 than the patients which did not develop metastasis. Analysis of Receiver Operating Characteristic Curves, Youden's Index and positive likelihood ratio values showed better diagnostic ability for IL-8 and MMP-9, which improved when both markers used together. Moreover, patients with age ≤60 years showed higher prognostic ability of metastasis development, which was significantly enhanced when patient age was analysed with IL-8. These results suggest potential of serum analytes (IL-8, MMP-9) and/or patient age in prognosticating the metastasis development in non-metastatic patients., Competing Interests: Declaration of Competing Interest None, (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Coronavirus disease-2019 (COVID-19) has become a global health crisis. Mortality associated with COVID-19 is characterized mainly by acute respiratory distress syndrome (ARDS), sepsis, pneumonia, and respiratory failure. The pathogenesis of the disease is known to be associated with pro-inflammatory processes after virus infection. Hence, various therapeutic strategies are being developed to control the inflammation and cytokine storm in COVID-19 patients. Recently, low-dose radiation therapy (LDRT) has been suggested for the treatment of pneumonia/ADRS in COVID-19 patients through irradiation of lungs by gamma/X-ray. In this direction, a few clinical trials have also been initiated. However, a few recent publications have raised some concerns regarding LDRT, especially about possibilities of activation/aggressiveness of virus (severe acute respiratory syndrome coronavirus 2 in case of COVID-19), lung injury and risk of second cancer after low-dose therapy. The present manuscript is an attempt to analyze these apprehensions based on cited references and other available literature, including some from our laboratory. At this point, LDRT may be not the first line of therapy. However, based on existing anti-inflammatory evidence of LDRT, it needs encouragement as an adjuvant therapy and for more multi-centric clinical trials. In addition, it would be worth combining LDRT with other anti-inflammatory therapies, which would open avenues for multi-modal therapy of pneumonia/ARDS in COVID-19 patients. The mode of irradiation (local lung irradiation or whole-body irradiation) and the window period after infection of the virus, need to be optimized using suitable animal studies for effective clinical outcomes of LDRT. However, considering ample evidence, it is time to look beyond the apprehensions if a low dose of radiation could be exploited for better management of COVID-19 patients., Competing Interests: There are no conflicts of interest., (Copyright: © 2020 Annals of Thoracic Medicine.)

We have developed surface functionalised Fe 3 O 4 magnetic nanoparticles (MNPs) based system that can be used for tumor-targeted multimodal therapies and MR imaging. Biocompatible, non-essential amino acid (glutamic acid) was introduced onto the surface of Fe 3 O 4 MNPs to provide functional sites for binding of chemotherapeutic drugs. These glutamic acid-coated Fe 3 O 4 MNPs (GAMNPs) exhibit good water-dispersibility, magnetic responsivity and pH dependent charge conversal feature. The magnetic core as well as organic shell of GAMNPs was characterized by XRD, TEM, DLS, FTIR, PPMS and UV-visible spectroscopy and zeta-potential analyzer etc. The broad spectrum anticancer drugs, doxorubicin hydrochloride (DOX) and methotrexate (MTX) were electrostatically and covalently conjugated to the surface of GAMNPs, respectively for combination chemotherapy. These dual drugs loaded system (DOX-MTX-GAMNPs) shows pH dependent release behaviour of both the drugs and enhanced toxicity towards breast cancer cell line (MCF-7) as compared to their individual treatment. Fluorescence microscopy and flow cytometric analyses confirmed the successful uptake of drug loaded system into MCF-7 cell lines. Further MTX being analogue of folic acid, its co-delivery with DOX would help in internalization of both the drugs into MCF-7 cells. These GAMNPs also show good heating efficiency under AC magnetic field (Intrinsic loss power, ILP = 0.95 and 0.73 and 0.48 nHm 2 /Kg at Fe concentration of 0.5, 1 and 2 mg/ml, respectively) and transverse relaxivity (r 2  = 152 mM -1  s -1 ) indicating their potential capability for hyperthermia therapy and MRI tracking. Furthermore, it has been observed that the combination of chemotherapeutic drugs and hyperthermia leads to an enhancement of cytotoxicity in MCF-7 cells., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier B.V.)

Nanoparticles coupled with targeting moieties have attracted a great deal of attention for cancer therapy since they can facilitate site-specific delivery of drug and significantly limit the side effects of systemic chemotherapy. In this study, our aim is to develop surface functionalized hydroxyapatite nanoparticles, which could provide binding sites for a cancer cell targeting ligand, folic acid (FA) as well as an anticancer drug, doxorubicin hydrochloride (DOX). In order to attain dual functionalities, hydroxyapatite nanoparticles were functionalized with gelatin molecules. Gelatin, being a protein has both carboxyl and amine moieties, which makes it suitable for binding of DOX and FA. FA was chemically conjugated to the nanoparticles through an EDCNHS coupling reaction. The formation of single-phase hydroxyapatite nanostructure was ascertained by X-ray diffraction studies and the presence of organic moieties on the surface of nanoparticles was evident from Fourier transform infrared spectroscopy, thermogravimetric analysis and U.V.-visible spectroscopy. The FA-conjugated nanoparticles (FA-Gel-HANPs) showed high affinity towards DOX and pH-responsive sustained release of drug with higher release rate under acidic pH conditions, desired for cancer therapy. The FA-Gel-HANPs showed negligible cytotoxicity towards different cell lines (HepG2, WEHI-164, KB, WI-26 VA4 and WRL-68). However, DOX loaded nanoparticles (DOX-FA-Gel-HANPs) exhibited significant toxicity towards these cells, which was however highest in folate receptor (FR)-overexpressing, KB cells. These results were correlated with enhanced cellular uptake of DOX-FA-Gel-HANPs in KB cells in comparison to FR-deficient, WRL-68 cells studied by confocal laser scanning microscopy and flow cytometry. Moreover, cell cycle analysis in KB cells, showed higher sub-G1 population, indicating apoptosis as one of the cell death mechanisms. Overall, this study suggests that DOX-FA-Gel-HANPs could serve as a promising tumor-targeted drug delivery system., Competing Interests: Declaration of Competing Interest There are no conflicts of interest to declare., (Copyright © 2019 Elsevier B.V. All rights reserved.)

To understand the biological effects of Thorium-232 (Th) in human cells and animal models as well as to assess mitigation strategies for its detoxification, there is a need to develop a sensitive, specific, high-throughput and easily-implementable assay for detection and estimation of Th in biological samples. Here, we have optimized arsenazo-III dye based colorimetric assay to detect Th in biological samples. The concentration of arsenazo-III (i.e. 50 µM) was optimized, which can reliably estimate Th in the concentration range of 2.5 to 40 µM. The optimized assay can specifically detect Th without interference from other metal ions (La, Ce, U, Fe, Ca, Cu, Zn and Mn). A significant correlation (R 2  = 0.999) was found between arsenazo-III-based detection of Th and total reflection X-ray fluorescence. The conditions of present assay successfully estimated Th in cell culture medium, cell harvesting (trypsin-EDTA) solution and cell lysate obtained from human liver cell culture. Moreover, for the first time, we detected Th in-situ in adherent liver cells in culture after staining with arsenazo-III. This study confirms that Th can be specifically determined in biological samples using arsenazo-III with the sensitivity, which is relevant to thorium toxicity research.

Purpose: Non-Targeted effects (NTE), such as bystander effect (BE) and genomic instability (GI) challenge central dogma of radiation biology. Moreover, there is a need to understand its universality in different type of cells and radiation quality. Materials and method: To study BE (primary and secondary) and GI Human adult dermal fibroblast (HADF) and peripheral blood lymphocytes (PBL) were exposed to low fluence of 241 Am alpha (α) particle and 6 MV X-ray. The BE was carried out by means of co-culture methodology after exposing the cells to both types of radiation and damage was measured using micronucleus assay (MN) and chromosomal aberration assay (CA) in the p1 cells while the GI was followed up in their progeny. Results: A dose-dependent increase in DNA damages (MN and CA) was observed in directly irradiated and bystander cells. The magnitude of BE was higher (6 fold) in cells co-cultured with the α-irradiated cells than that of with X-irradiated cells. Cross exposure of both cell types confirms that radiation induced BE is cell type dependent. In addition, induced DNA damage persisted for a longer population doubling in α-particle irradiated cells. Conclusion: This work adds evidence to secondary bystander response generated from primary bystander normal cells and its dependence to radiation quality.

Cancer stem cells (CSCs) have been implicated in growth, metastasis, recurrence and chemo-/radio-resistance in several cancer types. Despite a plenty of literature about different in vitro techniques to enrich/isolate CSCs, their comparative characterization for stemness is not well established. In the present study, cells obtained following three in vitro assays [clonogenic assay, tumorsphere assay (TSA) and single cell assay (SCA)] were compared for their cancer stem-like cell characteristics in human lung adenocarcinoma (A549) cells. Expression of the pluripotent (OCT4, NANOG) and lung cancer stem cell marker (CD166) genes were studied in these cells. Results showed that in comparison to cells obtained from routine culture (CC), the cells obtained from TSA showed significantly higher expression of OCT-4 and NANOG. These results were further validated with quantification of cell surface cancer stem cell markers i.e. CD44 + /CD24 - in the cells obtained from different methods, which were higher in TSA and SCA. Additionally, functional characterization of cancer stem-like cells (CSLCs) using ALDH assay showed the highest % of ALDH + cells in TSA. These results were in agreement with higher resistance of these cells against 5-Fluorouracil suggesting higher fraction of CSLCs in TSA than the other assays. These results showed that TSA provides a better method to enrich CSLCs in A549 lung adenocarcinoma cells., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

We report the development of pH-labile ascorbic acid-coated magnetic nanocarriers (AMNCs) for effective delivery of the anticancer drug doxorubicin hydrochloride (DOX) to tumor cells. The uniqueness of this drug delivery system lies in the covalent conjugation of DOX through carbamate and hydrazone bonds, resulting in a slow and sustained drug release profile at different environmental acidities. X-ray diffraction and transmission electron microscopy analyses reveal the formation of crystalline single-phase Fe 3 O 4 nanoparticles with an average size of 10 nm. The changes in the interfacial characteristics of the nanocarriers and the presence of organic coatings are probed by infrared spectroscopy, dynamic light scattering, zeta potential, and thermogravimetric measurements. AMNCs show high colloidal stability in aqueous and cell culture media and possess good magnetic field responsivity and protein resistance characteristics. The drug-loaded nanocarriers exhibited sustained pH-triggered release of drug molecules in acidic mediums, substantial cellular internalization, and significant toxicity toward the proliferation of mouse skin fibrosarcoma (WEHI-164), human breast cancer (MCF-7), and human lung cancer (A549) cells. However, it showed significantly lower toxicity in human normal lung (WI26VA) cells. Overall, these results suggest a pH-sensitive drug release of nanoformulations, which showed selective toxicity to tumor than normal cells., Competing Interests: The authors declare no competing financial interest.

Purpose: It is important to understand the significance of alpha (α) radiation-induced bystander effects (RIBE) and its relative biological effectiveness (RBE); this is because the phenomenon is not universal and the mechanism is unclear and because the RBE is widely varying and projected to be very high. Materials and methods: Isolated lymphocytes from healthy volunteers ( n  = 10) were exposed to either low fluence α-particles ( 241 Am), γ-rays ( 60 Co), or X-rays (225 kVp and 6 MV). Co-culture methodology was employed to investigate bystander effects (BEs). Chromosomal aberrations (CA) and micronucleus (MN) formation were used to study the BE and calculated RBE. Results: Lymphocytes directly exposed to the types of radiation used showed a dose-dependent increase in the frequency of CA and MN; dose independent increases in the frequency of these chromosomal damages in co-cultured bystander cells, implies that all three types of radiation-induced a BE. The calculated RBE at the level of 5% induced aberrations varied between 9 and 20. Conclusion: The magnitude of low fluence α-particle induced RIBE is higher than in low LET (linear energy transfer) radiation. The RBE also varies depending upon the endpoints used and adds up to targeted effects. Since the endpoint of CA is considered as an important and early marker of risk prediction, the RIBE and RBE using CA as a marker are relevant for radiation protection purposes.

Background: Nanoparticle-based therapies have emerged as a promising approach to overcome limitations of conventional chemotherapy. Present study investigates the potential of oleic acid-functionalized iron-oxide nanoparticles (MN-OA) to enhance the radiation response of fibrosarcoma tumor and elucidates its underlying mechanism., Methods: Various cellular and molecular assays (e.g. MTT, clonogenic, cell cycle analysis, cell death, DNA damage/repair) and tumor growth kinetics were employed to investigate the mechanism of MN-OA induced radio-sensitization., Results: Mouse (WEHI-164) and human (HT-1080) fibrosarcoma cells treated with MN-OA and gamma-radiation (2 Gy) showed a significant decrease in the cell proliferation. Combination treatment showed significant decrease in clonogenic survival of WEHI-164 cells and was found to induce cell cycle arrest, apoptosis and mitotic catastrophe. The mechanism of radio-sensitization was found to involve binding of MN-OA with HSP90, resulting in down-regulation of its client proteins, involved in cell cycle progression (Cyclin B1 and CDC2) and DNA-double strand break repair (e.g. RAD51 and BRCA1). Consistently, longer persistence of DNA damage in cells treated with MN-OA and radiation was observed in the form of γ-H2AX foci. The efficacy and mechanism of MN-OA-induced radio-sensitization was also validated in an immuno-competent murine fibrosarcoma model., Conclusion: This study reveals the key role of HSP90 in the mechanism of tumor radio-sensitization by MN-OA., General Significance: Present work provides a deeper understanding about the mechanism of MN-OA-induced tumor radiosensitization, highlighting the role of HSP90 protein. In addition to diagnostic and magnetic hyperthermia abilities, present remarkable radiosensitizing activity of MN-OA would further excite the clinicians to test its anti-cancer potential., (Copyright © 2019 Elsevier B.V. All rights reserved.)

During civil, nuclear or defense activities, internal contamination of actinides in humans and mitigation of their toxic impacts are of serious concern. Considering the health hazards of thorium (Th) internalization, an attempt was made to examine the potential of ten rationally-selected compounds/formulations to decorporate Th ions from physiological systems. The Th-induced hemolysis assay with human erythrocytes revealed good potential of tiron, silibin (SLB), phytic acid (PA) and Liv.52 ® (L52) for Th decorporation, in comparison to diethylenetriaminepentaacetic acid, an FDA-approved decorporation drug. This was further validated by decorporation experiments with relevant human cell models (erythrocytes and liver cells) and biological fluid (blood) under pre-/post-treatment conditions, using inductively coupled plasma mass spectrometry (ICP-MS) and transmission electron microscopy (TEM). Furthermore, density functional theory-based calculations and extended X-ray absorption fine structure (EXAFS) spectroscopy confirmed the formation of Th complex by these agents. Amongst the chosen biocompatible agents, tiron, SLB, PA and L52 hold promise to enhance Th decorporation for human application., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Monodispersed Fe 3 O 4 magnetic nanoparticles (MNPs) having size of 7 nm have been prepared from iron oleate and made water dispersible by functionalization for biomedical applications. Three different reactions employing thioglycolic acid, aspartic acid and aminophosphonate were performed on oleic acid coated Fe 3 O 4 . In order to achieve a control on particle size, the pristine nanoparticles were heated in presence of ferric oleate which led to increase in size from 7 to 11 nm. Reaction parameters such as rate of heating, reaction temperature and duration of heating have been studied. Shape of particles was found to change from spherical to cuboid. The cuboid shape in turn enhances magneto-crystalline anisotropy (K u ). Heating efficacy of these nanoparticles for hyperthermia was also evaluated for different shapes and sizes. We demonstrate heat generation from these MNPs for hyperthermia application under alternating current (AC) magnetic field and optimized heating efficiency by controlling morphology of particles. We have also studied intra-cellular uptake and localization of nanoparticles and cytotoxicity under AC magnetic field in human breast carcinoma cell line.

Purpose: One of the most important implications of 'Radiation Biology' research is to improve cancer radiotherapy with minimum side effects. In this regard, combination of chemotherapy with radiation has significantly improved tumor control as well as overall survival in a variety of cancers. However, this has been achieved at the cost of significant normal tissue toxicity, due to the lack of specificity of chemotherapy. Membrane-localized receptor tyrosine kinases (RTKs) have been found to play a driving role in various hallmarks of cancer. Moreover, an early successful clinical trial using RTK-antagonist (cetuximab) to improve tumor radiosensitivity has led to an advancement in this field of research. However, a comprehensive review integrating these findings of various oncogenic RTKs, from basic radiobiology-to-radiotherapy clinical trials, is lacking in literature. Therefore, the present review analyses relevant in-vitro, in-vivo, preclinical/clinical studies and postulates the concept of 'Radiation Biology of RTKs in Cancer'., Conclusions: The present review elucidates the effect of IR on various oncogenic RTKs and their mechanisms, downstream signaling, intracellular translocations, their role in the repair of radiation-induced DNA damage and post-irradiation survival. Based on the knowledge derived from RTK biology and the analysis of relevant clinical trials, this review attempts to identify radiobiological considerations, which could be implemented in future trials, combining radiotherapy with RTK-antagonist. Additionally, we identify the radiosensitizing potential of recently developed RTK-targeted nanoformulations. This review would probably change the Radiation Oncologist's view for translation of tumor-specific radiosensitization in clinic.

Highly water-dispersible surfactant-stabilized Fe 3 O 4 magnetic nanocarriers (SMNCs) were prepared by self-assembly of anionic surfactant, sodium dodecyl sulphate (SDS) on hydrophobic (oleic acid coated) nanoparticles and their biomedical applications were investigated. These nanocarriers have an average size of about 10nm and possess tunable surface charge properties. The formation of an organic coating of SDS was evident from infrared spectroscopy, dynamic light scattering, zeta-potential and thermogravimetric measurements. These nanocarriers were used for loading of both hydrophilic and hydrophobic anticancer agents such as doxorubicin hydrochloride (DOX) and curcumin (CUR), respectively. DOX was conjugated onto the surface of nanocarriers through electrostatic interaction, whereas CUR was encapsulated into the hydrophobic interlayer between oleic acid and SDS. The toxicity and cellular internalization of drug loaded nanocarriers were investigated against WEHI-164 cancer cell line. Specifically, the drug loading, pH sensitive drug release and cellular internalization studies suggested that these nanocarriers are suitable for dual drug delivery. Furthermore, they show good heating ability under AC magnetic field, thus can be used as effective heating source for hyperthermia treatment of cancer., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Chronic obstructive pulmonary disease (COPD) patients are at higher risk of developing lung cancer and its metastasis, but no suitable biomarker has been reported for differential diagnosis of these patients. Levels of serum biomarkers (VEGF, IL-8, MMP-9 and MMP-2) were analyzed in these patients, which were compared with healthy donors (HD). Levels of VEGF (P < 0.005) and MMP-9 (P < 0.05) were significantly higher in COPD patients than HD. Compared to HD, a decrease in IL-8 (~8.1 folds; P < 0.0001) but an increase in MMP-9 (~1.6 folds; P < 0.05) levels were observed in the lung cancer patients. Cancer patients showed significantly (P < 0.005) lower levels of serum VEGF (1.9 folds) and IL-8 (~9 folds) than the COPD patients. VEGF level was significantly higher (2.6 folds; P < 0.0005) in metastatic than non-metastatic cancer patients. However, MMP-2 didn't show significant variation in these patients. The Youden's index (YI) values for lung cancer diagnosis in HD using IL-8 was 0.55 with 83.3% overall accuracy. VEGF was able to diagnose COPD in HD with better YI (0.38) and overall accuracy (70.6%). IL-8 was able to diagnose cancer in COPD patients and HD with YI values of 0.35, 0.55 with 71% and 83.3% overall accuracy, respectively.

The interfacial engineering of magnetic nanoparticles (MNPs) with specific functional groups or targeting ligands is important for their in vivo applications. We report here the preparation and characterization of bifunctional magnetic nanoparticles (BMNPs) which contain a carboxylic moiety for drug binding and an amine moiety for folate mediated drug targeting. BMNPs were prepared by introducing bioactive cysteine molecules onto the surface of undecenoic acid coated Fe 3 O 4 magnetic nanoparticles (UMNPs) via a thiol-ene click reaction and then, folic acid was conjugated with these BMNPs through an EDC-NHS coupling reaction. X-ray diffraction (XRD) and transmission electron microscopy (TEM) analysis indicate the formation of highly crystalline single-phase Fe 3 O 4 nanostructures. The changes in the interfacial characteristics of the nanoparticles and the presence of an organic coating are evident from Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), zeta-potential measurement, and thermogravimetric analysis (TGA). These nanocarriers have an average size of 10 nm, and have a pH dependent charge conversional feature and protein resistance characteristic in physiological medium. These nanoparticles also show high loading affinity for an anticancer drug, doxorubicin hydrochloride (DOX) and its pH dependent release. This is highly beneficial for cancer therapy as the relatively low pH in tumors will specifically stimulate the drug release at the site of interest. Furthermore, our fluorescence microscopy and flow cytometry studies confirmed the higher cellular internalization capability of these folic acid conjugated nanoparticles in cancer cells over-expressing folate receptors.

Even though bystander effects pertaining to radiation risk assessment has been extensively studied, the molecular players of radiation induced bystander effect (RIBE) in the context of cancer radiotherapy are poorly known. In this regard, the present study is aimed to investigate the effect of irradiated tumor cells on the bystander counterparts in mouse fibrosarcoma (WEHI 164 cells) tumor model. Mice co-implanted with WEHI 164 cells γ-irradiated with a lethal dose of 15 Gy and unirradiated (bystander) WEHI 164 cells showed inhibited tumor growth, which was measured in terms of tumor volume and Luc+WEHI 164 cells based bioluminescence in vivo imaging. Histopathological analysis and other assays revealed decreased mitotic index, increased apoptosis and senescence in these tumor tissues. In addition, poor angiogenesis was observed in these tumor tissues, which was further confirmed by fluorescence imaging of tumor vascularisation and CD31 expression by immuno-histochemistry. Interestingly, the growth inhibitory bystander effect was exerted more prominently by soluble factors obtained from the irradiated tumor cells than the cellular fraction. Cytokine profiling of the supernatants obtained from the irradiated tumor cells showed increased levels of VEGF, Rantes, PDGF, GMCSF and IL-2 and decreased levels of IL-6 and SCF. Comparative proteomic analysis of the supernatants from the irradiated tumor cells showed differential expression of total 24 protein spots (21 up- and 3 down-regulated) when compared with the supernatant from the unirradiated control cells. The proteins which showed substantially higher level in the supernatant from the irradiated cells included diphosphate kinase B, heat shock cognate, annexin A1, angiopoietin-2, actin (cytoplasmic 1/2) and stress induced phosphoprotein 1. However, the levels of proteins like annexin A2, protein S100 A4 and cofilin was found to be lower in this supernatant. In conclusion, our results provided deeper insight about the damaging RIBE in an in vivo tumor model, which may have significant implication in improvement of cancer radiotherapy., Competing Interests: The authors have declared that no competing interests exist.

Background: Cancer stem cells (CSCs) are increasingly being realized to play a significant role in the mechanism of chemo-, radio-resistance, and metastasis of cancer. However, studies for spectral markers of CSCs using Fourier transform infrared (FT-IR) and circular dichroism (CD) spectroscopy are limited in the literature., Materials and Methods: In the present study, CSCs obtained from single cell assay of human lung adenocarcinoma (A549) cells were characterized using CD44+/CD24-/low phenotype expression, Hoechst 33342 dye efflux assay, and expression of stemness genes. Spectral changes in cancer cells and clones enriched with CSCs were studied by FT-IR and CD spectroscopy., Results: The changes in FT-IR spectra of clones enriched with CSCs showed the difference in the secondary protein structure as compared to nonstem cancer cells. Moreover, A549 clone cells showed higher C-O band of carbohydrates and deoxyribose ring vibrations of Z-form of DNA. These results were further corroborated with CD spectroscopy that showed increased alpha helix proteins and difference in DNA conformation in clones enriched with CSCs. FT-IR studies also showed higher imidazole-metal interactions in clones enriched with CSCs. These results are in agreement with higher activity of one of the metalloproteins that is, superoxide dismutase in clones enriched with CSCs and their increased radioresistance., Conclusions and General Significance: Overall, these observations provide novel FT-IR and CD spectroscopy signatures in A549 clones enriched with CSCs, which may have implications in the quantifying magnitude of CSCs as prognostic markers in cancer therapy.

Due to increasing use of lanthanides/actinides in nuclear and civil applications, understanding the impact of these metal ions on human health and environment is a growing concern. Hemoglobin (Hb), which occurs in all the kingdom of living organism, is the most abundant protein in human blood. In present study, effect of lanthanides and actinides [thorium: Th(IV), uranium: U(VI), lanthanum: La(III), cerium: Ce(III) and (IV)] on the structure and function of Hb has been investigated. Results showed that these metal ions, except Ce(IV) interacted with carbonyl and amide groups of Hb, which resulted in the loss of its alpha-helix conformation. However, beyond 75μM, these ions affected heme moiety. Metal-heme interaction was found to affect oxygen-binding of Hb, which seems to be governed by their closeness with the charge-to-ionic-radius ratio of iron(III). Consistently, Ce(IV) being closest to iron(III), exhibited a greater effect on heme. Binding constant and binding stoichiometry of Th(IV) were higher than that of U(VI). Experiments using aquatic midge Chironomus (possessing human homologous Hb) and human blood, further validated metal-Hb interaction and associated toxicity. Thus, present study provides a biochemical basis to understand the actinide/lanthanide-induced interference in heme, which may have significant implications for the medical and environmental management of lanthanides/actinides toxicity., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Human serum albumin (HSA), the most abundant soluble protein in blood plays critical roles in transportation of biomolecules and maintenance of osmotic pressure. In view of increasing applications of lanthanides- and actinides-based materials in nuclear energy, space, industries and medical applications, the risk of exposure with these metal ions is a growing concern for human health. In present study, binding interaction of actinides/lanthanides [thorium: Th(IV), uranium: U(VI), lanthanum: La(III), cerium: Ce(III) and (IV)] with HSA and its structural consequences have been investigated. Ultraviolet-visible, Fourier transform-infrared, Raman, Fluorescence and Circular dichroism spectroscopic techniques were applied to study the site of metal ions interaction, binding affinity determination and the effect of metal ions on protein unfolding and HSA conformation. Results showed that these metal ions interacted with carbonyl (CO..:)/amide(N..-H) groups and induced exposure of aromatic residues of HSA. The fluorescence analysis indicated that the actinide binding altered the microenvironment around Trp214 in the subdomain IIA. Binding affinity of U(VI) to HSA was slightly higher than that of Th(IV). Actinides and Ce(IV) altered the secondary conformation of HSA with a significant decrease of α-helix and an increase of β-sheet, turn and random coil structures, indicating a partial unfolding of HSA. A correlation was observed between metal ion's ability to alter HSA conformation and protein unfolding. Both cationic effects and coordination ability of metal ions seemed to determine the consequences of their interaction with HSA. Present study improves our understanding about the protein interaction of these heavy ions and their impact on its secondary structure. In addition, binding characteristics may have important implications for the development of rational antidote for the medical management of health effects of actinides and lanthanides., (Copyright © 2016 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.)

Purpose: Radionuclide therapy (RNT) is a rapidly growing area of clinical nuclear medicine, wherein radionuclides are employed to deliver cytotoxic dose of radiation to the diseased cells/tissues. During RNT, radionuclides are either directly administered or delivered through biomolecules targeting the diseased site. RNT has been clinically used for diverse range of diseases including cancer, which is the focus of the review., Conclusions: The major emphasis in RNT has so far been given towards developing peptides/antibodies and other molecules to conjugate a variety of therapeutic radioisotopes for improved targeting/delivery of radiation dose to the tumor cells. Despite that, many of the RNT approaches have not achieved their desired therapeutic success probably due to poor knowledge about complex and dynamic (i) fate of radiolabeled molecules; (ii) radiation dose delivered; (iii) cellular heterogeneity in tumor mass; and (iv) cellular radiobiological response. Based on understanding gathered during recent years, it may be stated that besides the absorbed dose, the net radiobiological response of tumor/normal cells also determines the clinical response of radiotherapeutic modalities including RNT. The radiosensitivity of tumor/normal cells is governed by radiobiological phenomenon such as radiation-induced bystander effect, genomic instability, adaptive response and low dose hyper-radiosensitivity. These concepts have been well investigated in the context of external beam radiotherapy, but their clinical implications during RNT have received meagre attention. In this direction, a few studies performed using in vitro and in vivo models envisage the possibilities of exploiting the radiobiological knowledge for improved therapeutic outcome of RNT.

Proton beam therapy is a cutting edge modality over conventional gamma radiotherapy because of its physical dose deposition advantage. However, not much is known about its biological effects vis-a-vis gamma irradiation. Here we investigated the effect of proton- and gamma- irradiation on cell cycle, death, epithelial-mesenchymal transition (EMT) and "stemness" in human non-small cell lung carcinoma cells (A549). Proton beam (3MeV) was two times more cytotoxic than gamma radiation and induced higher and longer cell cycle arrest. At equivalent doses, numbers of genes responsive to proton irradiation were ten times higher than those responsive to gamma irradiation. At equitoxic doses, the proton-irradiated cells had reduced cell adhesion and migration ability as compared to the gamma-irradiated cells. It was also more effective in reducing population of Cancer Stem Cell (CSC) like cells as revealed by aldehyde dehydrogenase activity and surface phenotyping by CD44(+), a CSC marker. These results can have significant implications for proton therapy in the context of suppression of molecular and cellular processes that are fundamental to tumor expansion., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Aim: There are various therapeutic modalities of treatment for non-Hodgkin's lymphoma, but with certain limitations, hence, investigating the scope of combined therapeutic approach., Materials and Methods: In this article, cellular toxicity, apoptosis and expression of mitogen-activated protein kinase signaling pathway proteins were investigated in Raji cells preincubated with doxorubicin followed by (131)I-rituximab (rituximab radiolabeled with Iodine-131) treatment., Results: It was found that the (131)I-rituximab in combination with doxorubicin showed a higher amount of cell toxicity and apoptosis compared to respective controls. Expression of anti-apoptotic protein (B-cell lymphoma-extra-large) was downregulated and cleavage of poly (ADP-ribose) polymerase, a marker of apoptosis was higher in cells treated with doxorubicin (2 μg/mL) and 131 I-rituximab (P ≤ 0.05). Moreover, in these cells the basal level of expression of p42/44 and p38 were increased while its phosphorylation was decreased., Conclusion: These results suggest that doxorubicin has the potential to sensitize (131)I-rituximab induced cell death in Raji cells.

Magnetic luminescent hybrid nanostructures (MLHN) have received a great deal of attention due to their potential biomedical applications such as thermal therapy, magnetic resonance imaging, drug delivery and intracellular imaging. We report the development of bifunctional Fe3O4 decorated YPO4:Eu hybrid nanostructures by covalent bridging of carboxyl PEGylated Fe3O4 and amine functionalized YPO4:Eu particles. The surface functionalization of individual nanoparticulates as well as their successful conjugation was evident from Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), zeta-potential and transmission electron microscopy (TEM) studies. X-ray diffraction (XRD) analysis reveals the formation of highly crystalline hybrid nanostructures. TEM micrographs clearly show the binding/anchoring of 10 nm Fe3O4 nanoparticles onto the surface of 100-150 nm rice grain shaped YPO4:Eu nanostructures. These MLHN show good colloidal stability, magnetic field responsivity and self-heating capacity under an external AC magnetic field. The induction heating studies confirmed localized heating of MLHN under an AC magnetic field with a high specific absorption rate. Photoluminescence spectroscopy and fluorescence microscopy results show optical imaging capability of MLHN. Furthermore, successful internalization of these MLHN in the cells and their cellular imaging ability are confirmed from confocal microscopy imaging. Specifically, the hybrid nanostructure provides an excellent platform to integrate luminescent and magnetic materials into one single entity that can be used as a potential tool for hyperthermia treatment of cancer and cellular imaging.

Anticancer activity of diospyrin and its derivatives (1-5) was evaluated against thirteen human cell lines. Compared to diospyrin (1), the acetylamine derivative (4) exhibited increase in cytotoxicity, particularly in HT-29 colon cancer cells, showing GI50 values of 33.90 and 1.96 μM, respectively. Also, enhanced toxicity was observed when cells, pre-treated with compound 4, were exposed to radiation. In vivo assessment of 4 was undertaken on tumour-bearing Nod-Scid mice treated at 4 mg/kg/day. Significant reduction in relative tumour volume (~86-91 %) was observed during the 12th-37th days after drug treatment. Increased caspase-3 activity and DNA ladder formation was observed in HT-29 cells after treatment with 4, suggesting induction of apoptotic death after drug treatment. Moreover, flow cytometric determination of Annexin V- FITC positive and PI negative cells demonstrated 17.4, 26.4, and 27.9 % of early apoptosis, respectively, upon treatment with 5, 10 and 25 μM of 4. HT-29 cells after treatment with 4 (1-25 μM) revealed ~2.5- 3- folds generation of ROS. Furthermore, concentration dependent decrease of mitochondrial trans-membrane potential (∆ψm), and expression of Bcl-2/Bax and other marker proteins suggested involvement of mitochondrial pathway of cell death. Overall, our results demonstrated the underlying cell-death mechanism of the plant-derived naphthoquinonoid (4), and established it as a prospective chemotherapeutic 'lead' molecule against colon cancer.

Purpose: We have evaluated the hyperthermia efficacy of oleic acid-functionalised Fe(3)O(4) magnetic nanoparticles (MN-OA) under in vivo conditions and elucidated the underlying mechanism of tumour growth inhibition., Materials and Methods: The efficacy and mechanism of tumour growth inhibition by MN-OA-mediated magnetic hyperthermia therapy (MHT) was evaluated in a murine fibrosarcoma tumour model (WEHI-164) using techniques such as TUNEL assay, Western blotting (WB), immunofluorescence (IF) staining and histopathological examination. In addition, bio-distribution of MN-OA in tumour/other target organs and its effect on normal organ function were studied by Prussian blue staining and serum biochemical analysis, respectively., Results: MN-OA-induced MHT resulted in significant inhibition of tumour growth as determined by measurement of tumour volume, as well as by in vivo imaging of tumour derived from luciferase-transfected WEHI-164 cells. Histopathology analysis showed presence of severe apoptosis and reduced tumour cells proliferation, which was further confirmed by TUNEL assay, reduced expression of Ki-67 and enhanced level of cleaved caspase-3, in tumours treated with MHT. Moreover, expression of heat stress marker, Hsp90 and its client protein, AKT/PKB was reduced by ∼50 and 80%, respectively, in tumours treated with MHT as studied by WB and IF staining. Serum analysis suggested insignificant toxicity of MN-OA (in terms of liver and kidney function), which was further correlated with minimal accumulation of MN-OA in target organs., Conclusions: These results suggest the involvement of apoptosis and Hsp90/AKT modulation in MN-OA-mediated MHT-induced tumour growth inhibition.

Radioresistance is one of the obstacles to the effective radiotherapy for non-small cell lung cancer. Soluble factors in the tumour microenvironment are often implicated in radioresistance but the underpinning mechanism(s) remain largely elusive. We herein studied the wholesome effect of autocrine cytokines and growth factors in the form of self-conditioned medium (CM) on the radiosensitivity of A549 cells. A549 cells grown in CM exhibited radioresistance which was associated with increased survival and DNA repair. CM induced pro-survival pathways through increased intracellular cAMP and phosphorylation of JNK and p38. Downstream to JNK/p38 signalling, ATF-2 phosphorylated at Thr69/71 was accompanied with its increased transcriptional activity in CM treated cells. Pre-treatment with cAMP inhibitor and silencing of ATF-2 abrogated the CM-induced survival. Interestingly, in cells treated with CM followed by radiation, ATF-2 was found to be switched over from transcription factor to DNA damage response protein. In CM treated cells, after γ-radiation p-ATF-2(Thr69/71) and subsequently the transcriptional activity of ATF-2 were declined with simultaneous rise in p-ATF-2(Ser490/498). Immunoprecipitation/immunoblotting and inhibitor studies showed that phosphorylation of ATF-2 at Ser490/498 was mediated by ATM. Moreover, p-ATF-2(Ser490/498) was found to be co-localised with γ-H2AX in DNA repair foci in CM-treated cells. The DNA repair activity of ATF-2 was assisted with higher activity MRN complex in cells grown in CM. Our study revealed that, autocrine soluble factors regulate dual but differential role of ATF-2 as a transcription factor or DNA repair protein, which collectively culminate in radioresistance of A549 cells., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Superparamagnetic Fe3O4 nanoparticles are appealing materials for heat activated killing of cancer cells. Here, we report a novel method to enhance the heat activated killing of cancer cells under an AC magnetic field (AMF) by introducing a polyaniline impregnated shell onto the surface of Fe3O4 nanoparticles. These polyaniline shell cross-linked magnetic nanoparticles (PSMN) were prepared by in situ polymerization of aniline hydrochloride on the surface of carboxyl PEGylated Fe3O4 nanoparticles. XRD and TEM analyses revealed the formation of single phase inverse spinel Fe3O4 nanoparticles of a size of about 10 nm. The successful growth of the polyaniline shell on the surface of carboxyl PEGylated magnetic nanoparticles (CPMN) is evident from FTIR spectra, DLS, TGA, zeta-potential and magnetic measurements. Both CPMN and PSMN show good colloidal stability, superparamagnetic behavior at room temperature and excellent heating efficacy under AMF. It has been observed that the heating efficacy of PSMN under AMF was slightly reduced as compared to that of CPMN. The enhanced toxicity of PSMN to cancer cells under AMF suggests their strong potential for magnetic hyperthermia. Furthermore, PSMN shows high loading affinity for an anticancer drug (doxorubicin), its sustained release and substantial internalization in tumor cells.

Most of the studies of radiation-induced bystander effects (RIBE) have been focused on understanding the radiobiological changes observed in bystander cells in response to the signals from irradiated cells in a normal cell population with implications to radiation risk assessment. However, reports on RIBE with relevance to cancer radiotherapy especially investigating the bidirectional and criss-cross bystander communications between cancer and normal cells are limited. Hence, in present study employing co-culture approach, we have investigated the bystander cross-talk between lung cancer (A549) and normal (WI38) cells after proton-microbeam irradiation using γ-H2AX foci fluorescence as a measure of DNA double-strand breaks (DSBs). We observed that in A549-A549 co-cultures, irradiated A549 cells exert damaging effects in bystander A549 cells, which were found to be mediated through gap junctional intercellular communication (GJIC). However, in A549-WI38 co-cultures, irradiated A549 did not affect bystander WI38 cells. Rather, bystander WI38 cells induced inverse protective signalling (rescue effect) in irradiated A549 cells, which was independent of GJIC. On the other hand, in response to irradiated WI38 cells neither of the bystander cells (A549 or WI38) showed significant increase in γ-H2AX foci. The observed bystander signalling between tumour and normal cells may have potential implications in therapeutic outcome of cancer radiotherapy., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Thorium-232 ((232)Th), a naturally-occurring actinide has gained significant attention due to its immense potential as a nuclear fuel for advanced reactors. Understanding the biological effects of (232)Th would significantly impact its efficient utilization with adequate health protection. Humans administered with (232)Th (thorotrast patients) or experimental animal models showed that liver is one of the major sites of (232)Th accumulation. Present study reports cellular effects of (232)Th-nitrate in a human-derived liver cell (HepG2). Results showed that the low concentration of (232)Th (0.1-10 μM) induced proliferation of HepG2 cells which was inhibited by the pre-treatment of cells with neutralizing antibody against insulin-like growth factor 1 receptor (IGF-1R). Consistently, (232)Th treatment was found to increase the phosphorylated level of IGF-1R-associated molecule, IRS1 which serves to activate PI3K and MAPK signaling pathways. Pre-treatment with specific inhibitors of PI3K (LY294002) or JNK-MAPK (SP600125) significantly abrogated the cytoproliferative effect of (232)Th. Immunofluorescence analysis showed increased levels of phospho-Akt and phospho-JNK, downstream kinases of IGF-1R, in (232)Th-treated HepG2 cells suggesting the role of IGF-1R-mediated signaling in (232)Th-stimulated cell proliferation. The cell cycle analysis showed that (232)Th increased S and G2-M cell fractions concomitant to the increase of cyclin-E level. Thus, the present investigation highlights the role of IGF-1R-mediated signaling in the cytoproliferative effect of (232)Th in human liver cells at low concentration., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)