Chronic Inhalation Exposure to Antimony Trioxide Exacerbates the MAPK Signaling in Alveolar Bronchiolar Carcinomas in B6C3F1/N Mice.

Antimony trioxide (AT) is used as a flame retardant in fabrics and plastics. Occupational exposure in miners and smelters is mainly through inhalation and dermal contact. Chronic inhalation exposure to AT particulates in B6C3F1/N mice and Wistar Han rats resulted in increased incidences and tumor multiplicities of alveolar/bronchiolar carcinomas (ABCs). In this study, we demonstrated Kras (43%) and Egfr (46%) hotspot mutations in mouse lung tumors (n = 80) and only Egfr (50%) mutations in rat lung tumors (n = 26). Interestingly, there were no differences in the incidences of these mutations in ABCs from rats and mice at exposure concentrations that did and did not exceed the pulmonary overload threshold. There was increased expression of p44/42 mitogen-activated protein kinase (MAPK) (Erk1/2) protein in ABCs harboring mutations in Kras and/or Egfr, confirming the activation of MAPK signaling. Transcriptomic analysis indicated significant alterations in MAPK signaling such as ephrin receptor signaling and signaling by Rho-family GTPases in AT-exposed ABCs. In addition, there was significant overlap between transcriptomic data from mouse ABCs due to AT exposure and human pulmonary adenocarcinoma data. Collectively, these data suggest chronic AT exposure exacerbates MAPK signaling in ABCs and, thus, may be translationally relevant to human lung cancers.

Clinicopathologic Features and Frozen Diagnostic Pitfalls of Bronchiolar Adenoma/Ciliated Muconodular Papillary Tumors (BA/CMPTs).

To describe the histologic features of bronchiolar adenoma/ciliated muconodular papillary tumors (BA/CMPTs) and analyze the pitfalls in diagnosis from frozen sections. A total of 208 frozen and permanent sections of BA/CMPTs from Shanghai Chest Hospital from July 2018 to July 2021 were retrospectively analyzed. The median age of BA/CMPT patients was 65 years (15 to 79 y), and women accounted for 61.62% (122/198). The median size of BA/CMPTs was 0.6 cm (range 0.2 to 2 cm), of which 88.94% were small (≤1 cm, 185/208). In terms of location, the right lower lobe accounted for 44.23% (92/208), and the left lower lobe accounted for 33.65% (70/208). In 10 patients with 2 independent BA/CMPTs, 5 lesions were located in the left lower lobe and 4 in the right lower lobe. A total of 86.06% of the CT images of BA/CMPT showed solid/subsolid nodules (179/208). Among 208 tumors, 68.75% were distal type (143/208), and 31.25% were proximal type (65/208). The qualitative error rate of frozen sections was 21.33% (32/150), of which the distal type accounted for 75% (24/32); most of them were misdiagnosed as invasive adenocarcinoma during frozen diagnosis. The frozen diagnosis of BA/CMPTs might result in misdiagnosis as invasive adenocarcinoma. A careful search for characteristics of BA/CMPT, such as bilayer epithelial cells with basal cells and a lack of cellular atypia and invasive growth patterns, may be helpful for frozen diagnosis.

Mechanisms facilitating the uptake of carboxyl-polythene glycol-functionalized gold nanoparticles into multicellular spheroids.

OBJECTIVES: Nanomedicines represent theragnostic alternatives to traditional candidate drugs, with increased targeting and delivery potential due to their size and functional tailorability. Biological activity typically relies on nanomaterials permeating into the intracellular environment, necessitating characterization of uptake and intracellular trafficking pathways. Spheroids' three-dimensional architecture and heterogenous cellular distribution offer an in-vivo-representative platform to assess the biological activity of nanoparticles (NPs). This study aimed to develop an A549 alveolar carcinoma spheroid model as a NP uptake assessment platform for carboxyl-polythene glycol-functionalized gold NPs affording further biological characterization opportunities in nanomedicine. METHODS: A549 spheroids were generated via the liquid overlay method, and their morphology and viability were assessed for 21 days. Cytotoxicity was assessed via lactate dehydrogenase release. NP uptake was elucidated using uptake pathway inhibition, combined with CytoViva hyperspectral imaging of sectioned spheroids to count internalized NPs. KEY FINDINGS: Cytotoxicity was absent for all exposure groups. Clathrin-mediated endocytosis was the primary endocytic mechanism (33.5-54.8% of uptake), which may precede lysosomal degradation. Lysosomal membrane permeabilization appears to be a potential downstream application. Low penetration into spheroids (4.5 µm) suggests the failure of NPs to traverse cellular layers in the spheroid. CONCLUSIONS: Although poor uptake was observed, a multicellular spheroid model of A549 alveolar carcinoma cells was established, allowing for similar future uptake assessment of various NPs.

Effect of cyanide ions (CN-) extracted from cassava (Manihotesculenta Crantz) on Alveolar Epithelial Cells (A549 cells).

Cassava (Manihotesculenta Crantz) is one of the most important root crops in tropical countries. It is a major source of cyanogenic glycosides viz. linamarin and lotaustralin, and these on breakdown liberate HCN and ketone. Cassava cyanide extract (CCE) from cassava leaves and tuber rinds were formulated as a biopesticide against certain borer insect pests of horticultural crops. Adenocarcinomic human alveolar basal epithelial cells (A549) were treated with three different concentrations (100, 200, 400 ppm) of CCE. The MTT and NRU assays showed dose-dependent cytotoxicity. The DCFH-DA assay does not show any free radical scavenging activity, whereas the NRR assay showed a reduction in the nitrile radicals with an increase in the concentration of the bioactive compound. A negative correlation was found between the concentration of the bioactive principles and mitochondrial and lysosomal functions. Various cellular assays demonstrated the cellular response of the CCE, and it was found that at higher concentration (400 ppm), the CCE exert a significant necrotic cell death rather than apoptosis. The results of the study indicated that the CCE have a remarkable tendency of anti-proliferative ability.

Cobalt-induced oxidative stress contributes to alveolar/bronchiolar carcinogenesis in B6C3F1/N mice.

Rodent alveolar/bronchiolar carcinomas (ABC) that arise either spontaneously or due to chemical exposure are similar to a subtype of lung adenocarcinomas in humans. B6C3F1/N mice and F344/NTac rats exposed to cobalt metal dust (CMD) by inhalation developed ABCs in a dose dependent manner. In CMD-exposed mice, the incidence of Kras mutations in ABCs was 67% with 80% of those being G to T transversions on codon 12 suggesting a role of oxidative stress in the pathogenesis. In vitro studies, such as DMPO (5,5-dimethyl-1-pyrroline N-oxide) immune-spin trapping assay, and dihydroethidium (DHE) fluorescence assay on A549 and BEAS-2B cells demonstrated increased oxidative stress due to cobalt exposure. In addition, significantly increased 8-oxo-dG adducts were demonstrated by immunohistochemistry in lungs from mice exposed to CMD for 90 days. Furthermore, transcriptomic analysis on ABCs arising spontaneously or due to chronic CMD-exposure demonstrated significant alterations in canonical pathways related to MAPK signaling (IL-8, ErbB, Integrin, and PAK pathway) and oxidative stress (PI3K/AKT and Melatonin pathway) in ABCs from CMD-exposed mice. Oxidative stress can stimulate PI3K/AKT and MAPK signaling pathways. Nox4 was significantly upregulated only in CMD-exposed ABCs and NOX4 activation of PI3K/AKT can lead to increased ROS levels in human cancer cells. The gene encoding Ereg was markedly up-regulated in CMD-exposed mice. Oncogenic KRAS mutations have been shown to induce EREG overexpression. Collectively, all these data suggest that oxidative stress plays a significant role in CMD-induced pulmonary carcinogenesis in rodents and these findings may also be relevant in the context of human lung cancers.

NAD+ metabolism controls growth inhibition by HIF1 in normoxia and determines differential sensitivity of normal and cancer cells.

The hypoxia-induced transcription factor HIF1 inhibits cell growth in normoxia through poorly understood mechanisms. A constitutive upregulation of hypoxia response is associated with increased malignancy, indicating a loss of antiproliferative effects of HIF1 in cancer cells. To understand these differences, we examined the control of cell cycle in primary human cells with activated hypoxia response in normoxia. Activated HIF1 caused a global slowdown of cell cycle progression through G1, S and G2 phases leading to the loss of mitotic cells. Cell cycle inhibition required a prolonged HIF1 activation and was not associated with upregulation of p53 or the CDK inhibitors p16, p21 or p27. Growth inhibition by HIF1 was independent of its Asn803 hydroxylation or the presence of HIF2. Antiproliferative effects of hypoxia response were alleviated by inhibition of lactate dehydrogenase and, more effectively, by boosting cellular production of NAD+, which was decreased by HIF1 activation. In comparison to normal cells, various cancer lines showed several fold-higher expressions of NAMPT, which is a rate-limiting enzyme in the main biosynthetic pathway for NAD+. Inhibition of NAMPT activity in overexpressor cancer cells sensitized them to antigrowth effects of HIF1. Thus, metabolic changes in cancer cells, such as enhanced NAD+ production, create resistance to growth-inhibitory activity of HIF1 permitting manifestation of its tumor-promoting properties.Abbreviations: DMOG: dimethyloxalylglycine, DM-NOFD: dimethyl N-oxalyl-D-phenylalanine, NMN: ß-nicotinamide mononucleotide.

PolyI:C suppresses TGF-ß1-induced Akt phosphorylation and reduces the motility of A549 lung carcinoma cells.

BACKGROUNDS: Epithelial mesenchymal transition (EMT) is a critical process involved in the invasion and metastasis of cancer, including lung cancer (LC). Transforming growth factor (TGF)-ß is one of factors capable of inducing EMT. Polyinosinic-polycytidylic acid (polyI:C), a synthetic agonist for toll-like receptor (TLR) 3, can enhance immune responses and has been used as an adjuvant for cancer vaccines; however, it remains unclear whether it influences other process, such as EMT. In the present study, we examined the effects of polyI:C on TGF-ß-treated A549 human LC cells. METHODS AND RESULTS: By in vitro cell proliferation assay, polyI:C showed no effect on the growth of A549 cells treated with TGF-ß1 at the concentration range up to 10 µg/ml; however, it markedly suppressed the motility in a cell scratch and a cell invasion assay. By Western blotting, polyI:C dramatically decreased TGF-ß1-induced Ak strain transforming (Akt) phosphorylation and increased phosphatase and tensin homologue (PTEN) expression without affecting the Son of mothers against decapentaplegic (Smad) 3 phosphorylation or the expression level of E-cadherin, N-cadherin or Snail, indicating that polyI:C suppressed cell motility independently of the 'cadherin switching'. The Akt inhibitor perifosine inhibited TGF-ß1-induced cell invasion, and the PTEN-specific inhibitor VO-OHpic appeared to reverse the inhibitory effect of polyI:C. CONCLUSION: PolyI:C has a novel function to suppress the motility of LC cells undergoing EMT by targeting the phosphatidylinositol 3-kinase/Akt pathway partly via PTEN and may prevent or reduce the metastasis of LC cells.

Downregulation of NKG2DLs by TGF-ß in human lung cancer cells.

BACKGROUND: Transforming growth factor beta (TGF-ß) is a typical immuno-inhibitory cytokine and highly secreted by lung cancer cells. It was supposed that its immunosuppressive effects to NK cell might be related with the altered expression of activating and inhibitory molecules in lung cancer cells. In this study, we examined the expression of NKG2DLs, PD-L1 and PD-L2 in lung cancer cells after treatment of TGF-ß and a TGF-ß inhibitor, Galunisertib (LY2157299). RESULTS: TGF-ß reduced the level of surface proteins of five NKG2DLs without altered transcription levels in lung cancer cells. Galunisertib reversed the effect of TGF-ß on the expression of NKG2DLs. Since MMP inhibitors, MMPi III and MMP2 inhibitor I, restored the reduced expression of NKG2DLs after treatment of TGF-ß, it was thought that TGF-ß induced the expression of MMP2 which facilitated the shedding of the NKG2DLs in cancer cells. However, the expression of PD-L1, L2 were not changed by treatment with TGF-ß or Galunisertib. CONCLUSIONS: Therefore, inhibition of TGF-ß might reverse the immunosuppressive status on immune cells and restore NK cell mediated anticancer immune responses by upregulation of NKG2DLs in cancer cells.

Sensitive imaging of tumors using a nitroreductase-activated fluorescence probe in the NIR-II window.

A nitroreductase (NTR)-activated NIR-II fluorescence probe for tumor imaging is reported. The probe can emit fluorescence in the range of 900-1300 nm, and target hypoxic tumors with NTR overexpression, thus allowing for accurate delineation of tumor margins through deep penetration.

High-Contrast Fluorescence Diagnosis of Cancer Cells/Tissues Based on ß-Lapachone-Triggered ROS Amplification Specific in Cancer Cells.

Discrimination of cancer cells/tissues from normal ones is of critical importance for early diagnosis and treatment of cancers. Herein, we present a new strategy for high-contrast fluorescence diagnosis of cancer cells/tissues based on ß-Lapachone (ß-Lap, an anticancer agent) triggered ROS (reactive oxygen species) amplification specific in cancer cells/tissues. With the strategy, a wide range of cancer cells/tissues, including surgical tissue specimens harvested from patients, were distinguished from normal ones by using a combination of ß-Lap and a Si-rhodamine-based NIR fluorescent ROS probe PSiR3 developed in this work with average tumor-to-normal (T/N) ratios up to 15 in cell level and 24 in tissue level, far exceeding the clinically acceptable threshold of 2.0. What's more, the strategy allowed the fluorescence discrimination of tumor tissues from inflammatory ones based on whether a marked fluorescence enhancement could be induced when treated with PSiR3 and ß-Lap/PSiR3 combination, respectively.

One- and Two-Photon Phototherapeutic Effects of RuII Polypyridine Complexes in the Hypoxic Centre of Large Multicellular Tumor Spheroids and Tumor-Bearing Mice*.

During the last decades, photodynamic therapy (PDT), an approved medical technique, has received increasing attention to treat certain types of cancer. Despite recent improvements, the treatment of large tumors remains a major clinical challenge due to the low ability of the photosensitizer (PS) to penetrate a 3D cellular architecture and the low oxygen concentrations present in the tumor center. To mimic the conditions found in clinical tumors, exceptionally large 3D multicellular tumor spheroids (MCTSs) with a diameter of 800 µm were used in this work to test a series of new RuII polypyridine complexes as one-photon and two-photon PSs. These metal complexes were found to fully penetrate the 3D cellular architecture and to generate singlet oxygen in the hypoxic center upon light irradiation. While having no observed dark toxicity, the lead compound of this study showed an impressive phototoxicity upon clinically relevant one-photon (595 nm) or two-photon (800 nm) excitation with a full eradication of the hypoxic center of the MCTSs. Importantly, this efficacy was also demonstrated on mice bearing an adenocarcinomic human alveolar basal epithelial tumor.

Ratiometric Fluorescence Imaging for the Distribution of Nucleic Acid Content in Living Cells and Human Tissue Sections.

The misregulation of nucleic acids behavior leads to cell dysfunction and induces serious diseases. A ratiometric fluorescence probe is a powerful tool to study the dynamic behavior and function relationships of nucleic acids. However, currently, no such effective probe has been reported for in situ, real-time tracking of nucleic acids in living cells and tissue sections. Herein, the unique probe named QPP-AS was rationally designed for ratiometric fluorescence response to nucleic acids through skillful regulation of the intramolecular charge-transfer capabilities of the electron acceptor and donor. Encouraged by the advantages of the selective nucleic acid response, ideal biocompatibility, and high signal-to-noise ratio, QPP-AS has been applied for in situ, real-time ratiometric fluorescence imaging of nucleic acids in living cells for the first time. Furthermore, we have demonstrated that QPP-AS is capable of visualizing the dynamic behavior of nucleic acids during different cellular processes (e.g., cell division and apoptosis) by ratiometric fluorescence imaging. More significantly, QPP-AS has been successfully used for ratiometric fluorescence imaging of nucleic acids in human tissue sections, which provides not only the cell contour, nuclear morphology, and nuclear-plasma ratio but also the nucleic acid content information and may greatly improve accuracy in clinicopathological diagnosis.

125I seeds irradiation inhibits tumor growth and induces apoptosis by Ki-67, P21, survivin, livin and caspase-9 expression in lung carcinoma xenografts.

BACKGROUND: Lung cancer is a fatal disease and a serious health problem worldwide. Patients are usually diagnosed at an advanced stage, and the effectiveness of chemotherapy for such patients is very limited. Iodine 125 seed (125I) irradiation can be used as an important adjuvant treatment for lung carcinoma. The purpose of this study was to examine the role of irradiation by 125I seeds in human lung cancer xenograft model and to determine the underlying mechanisms involved, with a focus on apoptosis. METHODS: 40 mice with A549 lung adenocarcinoma xenografts were randomly divided into 4 groups: control group (n = 10), sham seed (0 mCi) implant group (n = 10), 125I seed (0.6 mCi) implant group (n = 10) and 125I seed (0.8 mCi) implant group (n = 10), respectively. The body weight and tumor volume, were recorded every 4 days until the end of the study. Apoptotic cells were checked by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and activities of caspase-3 and caspase-8 enzyme were tested. Expression of P21, survivin, livin, caspase-9 and proliferating cell nuclear antigen (Ki-67) was detected with immunohistochemical staining. RESULTS: The results of TUNEL staining assays showed that 125I seed irradiation suppresses the growth of lung cancer xenografts in nude mice and induced apoptosis. The activity of caspase-3 and caspase-8 was significantly higher. The expression levels Ki67, survivin and livin were substantially downregulated, while P21 and caspase-9 protein expression were significantly increased following 125I seed irradiation. This study revealed that 125I seed irradiation could significantly change apoptosis-related protein in human lung cancer xenografts. CONCLUSIONS: Overall, our study demonstrates that radiation exposure by 125I seeds could be a new treatment option for lung cancer.

Typical presentation of pulmonary lepidic adenocarcinoma: a rare case report.

Bronchioloalveolar carcinoma (BAC) is a rare subtype of adenocarcinoma of lung with distinct features and distinctive characteristics. It accounts approximately for 4% of lung cancers. In the following study we report a rare observation of a 50 years old female with a clinical, radiological and histological presentation, which is typical of an invasive mucinous lepidic adenocarcinoma formerly named BAC.

Hyaluronan decoration of milk exosomes directs tumor-specific delivery of doxorubicin.

Milk exosomes (mExo), similar to cell-derived exosomes, are emerging as promising nanocarriers for delivery of therapeutic molecules such as chemical drugs and siRNA, due to the excellent biocompatibility and low-cost production from bovine milk. However, additional modification remains required to apply milk exosomes for tumor-specific drug delivery. Here, we attempted to develop a novel strategy for directing doxorubicin (Dox)-loaded mExo to CD44-overexpressing tumor cells. Hyaluronan (HA), a CD44-specific ligand, was functionalized with an amphiphilic molecule DSPE-PEG2000, which enabled the spontaneous decoration of Dox-loaded mExo with HA onto the phospholipid bilayer. The obtained nanocarrier HA-mExo-Dox was shown to be able to selectively deliver Dox into cells with over-expressed CD44 instead of control cells and trigger the notable tumor cells death in the in vitro analysis. This study demonstrates the potential use of HA-displaying mExo for tumor cell-specific drug delivery and this strategy should prove to be feasible for targeted cancer therapy.

Plant growth regulators and Axl and immune checkpoint inhibitors from the edible mushroom Leucopaxillus giganteus.

A novel compound, (R)-4-ethoxy-2-hydroxy-4-oxobutanoic acid (1), and six known compounds (2-7) were isolated from the fruiting bodies of the wild edible mushroom Leucopaxillus giganteus. The planar structure of 1 was determined by the interpretation of spectroscopic data analysis. The absolute configuration of 1 was determined by comparing specific rotation of the synthetic compounds. In the plant regulatory assay, the isolated compounds (1-7) and the chemically prepared compounds (8-10) were evaluated their biological activity against the lettuce (Lactuca sativa) growth. Compounds 1 and 3-10 showed the significant regulatory activity of lettuce growth. 1 showed the strongest inhibition activity among the all the compounds tested. In the lung cancer assay, all the compounds were assessed the mRNA expression of Axl and immune checkpoints (PD-L1, PD-L2) in the human A549 alveolar epithelial cell line by RT-PCR. Compounds 1-10 showed significant inhibition activity against Axl and/or immune checkpoint.

Tumor-targeting multi-shelled hollow nanospheres as drug loading platforms for imaging-guided combinational cancer therapy.

In this work, we developed multi-shelled hollow nanospheres [RGD@am-ZnO@CuO@Au@DOX HNSs] as multifunctional therapeutic agents to achieve effective and targeted Zn2+/Cu2+ therapy, induced drug delivery under low pH/red-light conditions, and enhanced phototherapy under single red-light. The photothermal and photodynamic performance of am-ZnO@CuO@Au HNSs was enhanced relative to that of am-ZnO nanoparticles (NPs) or am-ZnO@CuO HNSs by utilizing the resonance energy transfer process and broad red-light absorption. The pH-sensitive am-ZnO@CuO@Au HNSs were dissolved to Zn2+/Cu2+ in the acidic endosomes/lysosomes of cancer cells, resulting in a cancer cell killing effect. The release performance of doxorubicin (DOX) from RGD@am-ZnO@CuO@Au@DOX HNSs was evaluated under low pH and red-light-irradiated conditions, and targeting of HNSs was confirmed by dual-modal imaging (magnetic resonance/fluorescence) of the tumor area. Moreover, in vivo synergistic therapy using RGD@am-ZnO@CuO@Au@DOX HNSs was further evaluated in mice bearing human pulmonary adenocarcinoma (A549) cells, achieving a remarkable synergistic antitumor effect superior to that obtained by monotherapy. This study validated that RGD@am-ZnO@CuO@Au@DOX HNSs can be a promising candidate for efficient postoperative cancer therapy.

The Reverse Warburg Effect is Associated with Fbp2-Dependent Hif1α Regulation in Cancer Cells Stimulated by Fibroblasts.

Fibroblasts are important contributors to cancer development. They create a tumor microenvironment and modulate our metabolism and treatment resistance. In the present paper, we demonstrate that healthy fibroblasts induce metabolic coupling with non-small cell lung cancer cells by down-regulating the expression of glycolytic enzymes in cancer cells and increasing the fibroblasts' ability to release lactate and thus support cancer cells with energy-rich glucose-derived metabolites, such as lactate and pyruvate-a process known as the reverse Warburg effect. We demonstrate that these changes result from a fibroblasts-stimulated increase in the expression of fructose bisphosphatase (Fbp) in cancer cells and the consequent modulation of Hif1α function. We show that, in contrast to current beliefs, in lung cancer cells, the predominant and strong interaction with the Hif1α form of Fbp is not the liver (Fbp1) but in the muscle (Fbp2) isoform. Since Fbp2 oligomerization state and thus, its role is regulated by AMP and NAD+-crucial indicators of cellular metabolic conditions-we hypothesize that the Hif1α-dependent regulation of the metabolism in cancer is modulated through Fbp2, a sensor of the energy and redox state of a cell.