Small cell lung carcinoma (SCLC) is a highly aggressive malignancy that is typically associated with tobacco exposure and inactivation of RB1 and TP53 genes. Here, we performed detailed clinicopathologic, genomic, and transcriptomic profiling of an atypical subset of SCLC that lacked RB1 and TP53 co-inactivation and arose in never/light smokers. We found that most cases were associated with chromothripsis—massive, localized chromosome shattering—recurrently involving chromosome 11 or 12 and resulting in extrachromosomal amplification of CCND1 or co-amplification of CCND2/CDK4/MDM2, respectively. Uniquely, these clinically aggressive tumors exhibited genomic and pathologic links to pulmonary carcinoids, suggesting a previously uncharacterized mode of SCLC pathogenesis via transformation from lower-grade neuroendocrine tumors or their progenitors. Conversely, SCLC in never-smokers harboring inactivated RB1 and TP53 exhibited hallmarks of adenocarcinoma-to-SCLC derivation, supporting two distinct pathways of plasticity-mediated pathogenesis of SCLC in never-smokers. Significance: Here, we provide the first detailed description of a unique SCLC subset lacking RB1/TP53 alterations and identify extensive chromothripsis and pathogenetic links to pulmonary carcinoids as its hallmark features. This work defines atypical SCLC as a novel entity among lung cancers, highlighting its exceptional histogenesis, clinicopathologic characteristics, and therapeutic vulnerabilities. See related commentary by Nadeem and Drapkin, p. 8

Antibiotic-resistant Pseudomonas aeruginosa (P. aeruginosa) is one of the most critical pathogens in wound infections, causing high mortality and morbidity in severe cases. However, bacteriophage therapy is a potential alternative to antibiotics against P. aeruginosa. Therefore, this study aimed to isolate a novel phage targeting P. aeruginosa and examine its efficacy in vitro and in vivo. The morphometric and genomic analyses revealed that ZCPA1 belongs to the Siphoviridae family and could infect 58% of the tested antibiotic-resistant P. aeruginosa clinical isolates. The phage ZCPA1 exhibited thermal stability at 37 °C, and then, it decreased gradually at 50 °C and 60 °C. At the same time, it dropped significantly at 70 °C, and the phage was undetectable at 80 °C. Moreover, the phage ZCPA1 exhibited no significant titer reduction at a wide range of pH values (4–10) with maximum activity at pH 7. In addition, it was stable for 45 min under UV light with one log reduction after 1 h. Also, it displayed significant lytic activity and biofilm elimination against P. aeruginosa by inhibiting bacterial growth in vitro in a dose-dependent pattern with a complete reduction of the bacterial growth at a multiplicity of infection (MOI) of 100. In addition, P. aeruginosa-infected wounds treated with phages displayed 100% wound closure with a high quality of regenerated skin compared to the untreated and gentamicin-treated groups due to the complete elimination of bacterial infection. The phage ZCPA1 exhibited high lytic activity against MDR P. aeruginosa planktonic and biofilms. In addition, phage ZCPA1 showed complete wound healing in the rat model. Hence, this research demonstrates the potential of phage therapy as a promising alternative in treating MDR P. aeruginosa.

(Background): Multi-drug-resistant Klebsiella pneumoniae (MDR-KP) has steadily grown beyond antibiotic control. Wound infection kills many patients each year, due to the entry of multi-drug resistant (MDR) bacterial pathogens into the skin gaps. However, a bacteriophage (phage) is considered to be a potential antibiotic alternative for treating bacterial infections. This research aims at isolating and characterizing a specific phage and evaluate its topical activity against MDR-KP isolated from infected wounds. (Methods): A lytic phage ZCKP8 was isolated by using a clinical isolate KP/15 as a host strain then characterized. Additionally, phage was assessed for its in vitro host range, temperature, ultraviolet (UV), and pH sensitivity. The therapeutic efficiency of phage suspension and a phage-impeded gel vehicle were assessed in vivo against a K. pneumoniae infected wound on a rat model. (Result): The phage produced a clear plaque and was classified as Siphoviridae. The phage inhibited KP/15 growth in vitro in a dose-dependent pattern and it was found to resist high temperature (˂70 °C) and was primarily active at pH 5; moreover, it showed UV stability for 45 min. Phage-treated K. pneumoniae inoculated wounds showed the highest healing efficiency by lowering the infection. The quality of the regenerated skin was evidenced via histological examination compared to the untreated control group. (Conclusions): This research represents the evidence of effective phage therapy against MDR-KP.

Purpose: Diabetes mellitus is among the disrupting factors of orchestrated events in wound healing. This necessitates the urge for tailored medications, which are continually offered by nano-sized materials. Herein, we present greenly synthesized copper oxide nanoparticles (CuO NPs), obtained from either Punica granatum L. (PG) or Pisidium guajava L. (GV) extract, to function as potent bactericidal and fungicidal materials that promote regeneration and healing of the targeted diabetic wounded tissues. Methods: PG or GV plant extracts were compared as source of reducing agents for CuO NPs synthesis process. The yield and photocatalytic degradation potential were compared. NPs obtained from the superior extract, PG, were characterized using particles size, zeta potential, XRD, TEM, SEM, and EDX. The antimicrobial effects were evaluated on multidrug-resistant human pathogens and then the percentage biofilm inhibitory concentration was determined. The cytotoxicity and wound scratch study were conducted on a normal human skin cell line. In-vivo wound healing activity in diabetic rats was assessed along with histopathological and immunohistochemical examination of CD45 and α-SMA. Results: The greenly synthesized CuO NPs are spherical in shape having a diameter of 233nm. CuO NPs (250μg/mL) acted as promising biocontrol agent against a variety of multidrug-resistant human pathogens. They significantly exhibited 29.460± 0.811% healing of the scratched wound compared to only 2.001± 0.155% for the control. Wound healing experiments revealed the safety of a low CuO NPs concentration in a diabetic animal model as well as on human normal skin fibroblast cell line. The treated group with a dose of 2mg/cm² showed superior results with a WC50 value of 7.2 days, and 92% wound contraction after 13-days. Immunohistochemical investigation of the same group demonstrated well-established fibrous tissue (5.7± 3.7/HPF), and an amplified granulation tissue of recently developed blood vessels (70± 1.5/HPF). Conclusion: Green synthesized CuO NPs could overcome drug resistance and promote wound healing process effectively.

Exaggerated neuronal excitation by glutamate is a well-known cause of excitotoxicity, a key factor in numerous neurodegenerative disorders. This study examined the neurotoxic effect of monosodium glutamate (MSG) in the brain cortex of rats and focused on assessing the potential neuroprotective effects of omega-3 polyunsaturated fatty acids (ω-3 PUFAs). Four groups of adult male rats (n = 10) were assigned as follows; normal control, ω-3 PUFAs (400 mg/kg) alone, MSG (4 mg/g) alone, and MSG plus ω-3 PUFAs (4 mg/g MSG plus 400 mg/kg ω-3 PUFAs). Biochemical analysis, immunohistochemical, and histological examinations were conducted upon completion of the treatment protocol. Results revealed that MSG significantly increased malondialdehyde, nitric oxide, tumor necrosis factor-α, interleukin 1β, acetylcholinesterase, monoamine oxidase, and caspase-3. However, the MSG-treated group showed a decline in reduced glutathione, catalase, superoxide dismutase, dopamine, and serotonin. In addition, MSG caused histopathological changes in the cortical region which support the biochemical and immunohistochemical analysis. Supplementation of ω-3 PUFAs greatly improved the biochemical, immunohistochemical, and histopathological alterations induced by MSG administration in the brain cortex. Together, these findings revealed a neuroprotective effect of ω-3 PUFAs against MSG-induced toxicity in the brain cortex by attenuating oxidative damage, inflammation, neurochemical perturbations, and apoptosis. Graphical abstract

Epidermal Growth Factor Receptor (EGFR) targeting therapies are currently of great relevance for the treatment of lung cancer. For this reason, in addition to mutational analysis immunohistochemistry (IHC) of EGFR in lung cancer has been discussed for the decision making of according therapeutic strategies. The aim of this study was to obtain standardization of EGFR-expression methods for the selection of patients who might benefit of EGFR targeting therapies. As a starting point of a broad investigation, aimed at elucidating the expression of EGFR on different biological levels, four EGFR specific antibodies were analyzed concerning potential differences in expression levels by Immunohistochemistry (IHC) and correlated with fluorescence in situ hybridization (FISH) analysis and clinicopathological data. 206 tumor tissues were analyzed in a tissue microarray format employing immunohistochemistry with four different antibodies including Dako PharmDx kit (clone 2-18C9), clone 31G7, clone 2.1E1 and clone SP84 using three different scoring methods. Protein expression was compared to FISH utilizing two different probes. EGFR protein expression determined by IHC with Dako PharmDx kit, clone 31G7 and clone 2.1E1 (p ≤ 0.05) correlated significantly with both FISH probes independently of the three scoring methods; best correlation is shown for 31G7 using the scoring method that defined EGFR positivity when ≥ 10% of the tumor cells show membranous staining of moderate and severe intensity (p = 0.001). Overall, our data show differences in EGFR expression determined by IHC, due to the applied antibody. Highest concordance with FISH is shown for antibody clone 31G7, evaluated with score B (p = 0.001). On this account, this antibody clone might by utilized for standard evaluation of EGFR expression by IHC. The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_165