Transcription factor 4 expression and correlation with tumor progression in gallbladder cancer.

Background: Dysregulation in Wnt/ß-catenin signaling has been associated with the initiation and metastasis of cancer cells. Transcription factor 4 (TCF4) (also named as transcription factor 7-like 2) is a key transcriptional factor of the Wnt signaling pathway, which, when interact with ß-catenin activates Wnt genes which plays an essential role in tumor development. The expression pattern and clinical significance of TCF4 in gallbladder cancer (GBC) are not yet established. Aims: This study was performed to assess the expression pattern of TCF4 in GBC tissue and attempted to correlate its expression with different clinicopathological parameters. Materials and Methods: The study was conducted on 33 surgically resected specimens of gallbladder carcinoma (GBC) and 12 cases of chronic cholecystitis (CC) as control, which had been confirmed from histology. The expression of TCF4 was performed by the reverse transcription polymerase chain reaction and immunohistochemistry. Results: Relative mRNA expression levels of ß-catenin and TCF4 in GBC tissues were significantly (P < 0.05) higher than in CC samples. TCF4 protein expression was observed in 81.82% (27/33) GBC cases. Specifically, among GBC samples, 21.21% (7/33) was graded as strongly positive, 60.61% (20/33) graded as moderately positive, whereas 18.18% (6/33) graded as negative. All 12 CC samples graded as negative. Overall, TCF4 expression in GBC tissues was statistically significant over CC samples (P < 0.05). Moreover, we observed that TCF4 expression was significantly higher (P < 0.05) in high tumor grades than low grade, higher (P < 0.05) in Stage 2 and Stage 3 than Stage 1. Conclusion: The present study suggests that TCF4 may exert an oncogenic role in the progression of GBC and may serve as a new potential candidate biomarker for tumor progression, and it might be a potential therapeutic target against GBC.

Design, synthesis and evaluation of 4,7-disubstituted 8-methoxyquinazoline derivatives as potential cytotoxic agents targeting ß-catenin/TCF4 signaling pathway.

Overactivation of Wnt/ß-catenin signaling by accumulated ß-catenin in the nucleus has been shown to play a crucial role in the etiology of cancer. Interaction of ß-catenin with Transcription factor 4 (TCF4) is a key step for the activation of Wnt genes in response to upstream signals of the Wnt/ß-catenin pathway. Hence, down regulation of Wnt/ß-catenin signaling or targeting downstream events by selective ß-catenin/TCF4 protein-protein interaction inhibitors could be a potential therapeutic strategy against such cancers. In this study structure-based drug design approach was followed to design novel 4,7-disubstituted 8-methoxyquinazoline-based derivatives which could act as potential cytotoxic agents inhibiting the ß-catenin/TCF4 protein-protein interactions. Fifteen compounds possessing 4,7-disubstituted 8-methoxyquinazoline scaffold were synthesized. Cytotoxic potential of the synthesised derivatives were determined against constitutively activated ß-catenin/TCF4 signaling pathway cancer cells (HCT116 and HepG2) using the sulforhodamine B assay. The most potent compound (18B) was selected for detailed biological evaluation. Cell morphology, Hoechst 33342 and Annexin V/PI staining were used to detect apoptosis, while inhibition of cell migration was assessed by in vitro wound healing assay against HCT116 and HepG2 cells. Effect on ß-catenin/TCF mediated transcriptional activity was assessed by TOPFlash/FOPFlash assay, TCF4 and ß-catenin protein expression by immunocytofluorescence, and Wnt target genes (like c-MYC and Cyclin D1) mRNA levels by RT-PCR against HCT116 cells. Cytotoxic potency of the most potential compound (18B) against primary human gallbladder cancer cells was also evaluated. The derivatives showed interactions with active site residues of ß-catenin and were capable of hindering the TCF4 binding, thereby disrupting ß-catenin/TCF4 interactions. Cytotoxic potencies (IC50) of these derivatives ranged from 5.64 ± 0.68 to 23.18 ± 0.45 µM against HCT116 and HepG2 cells respectively. Compound (18B), the most potent compound among the series, induced apoptosis and inhibited cell migration against HCT116 and HepG2 cells. Mechanistic studies indicated that compound (18B) downregulated ß-catenin/TCF4 signaling pathway, ß-catenin and TCF4 protein expression, and mRNA levels of c-MYC andCyclin D1 in HCT116 cells and showed cytotoxicity against primary human gallbladder cancer cells with IC50 value of 8.50 ± 1.44 µM. Thus, novel 4,7-disubstituted 8-methoxyquinazoline derivatives were identified as potential cytotoxic agents with potencies comparable to that of imatinib mesylate. Compound (18B) represents a promising lead molecule as anticancer agent against colon, hepatocellular and gallbladder cancers targeting ß-catenin/TCF4 signaling pathway.

Formulation and in vivo efficacy study of cetuximab decorated targeted bioadhesive nanomedicine for non-small-cell lung cancer therapy.

Aim: To design, optimize and evaluate docetaxel-loaded chitosan nanoparticles with (targeted) and without (nontargeted) cetuximab conjugation for the treatment of non-small-cell lung cancer (NSCLC). Materials & methods: Risk-assessment, optimization, in vitro characterizations, stability assessments, release studies, cell-culture studies were performed along with histopathology, pharmacokinetic and anticancer efficacy studies. Results: The nanoparticles of desired particle size (152.59 ± 3.90 nm to 180.63 ± 5.21 nm) which could sustain drug release for up to 70 h, were obtained. The cell-culture studies demonstrated the superiority of the formulations over Docel™. The pharmacokinetic evaluation showed the excellent systemic bioavailability of prepared NPs. The histopathology screening revealed lesser toxicity of both the nontargeted and targeted formulations. The targeted nanoformulation significantly reduced tumor growth than the nontargeted formulation and Docel. Conclusion: These results demonstrate the therapeutic potential of the prepared nanoformulation. After proper clinical validation, it could be a promising approach for the treatment of NSCLC.

Caffeine-enhanced anti-tumor activity of anti-PD1 monoclonal antibody.

Antibodies targeting PD1 receptor have emerged as a promising therapeutic strategy against multiple types of solid cancers. However, relatively low complete response rates observed with anti-PD1 mAb monotherapy emphasizes the importance of testing new immunotherapeutic combinations. The production of extracellular adenosine in solid tumors was recently identified as a major immunosuppressive pathway, targeting this pathway would enhance the therapeutic activity of anti-PD1 mAbs. In this study, we evaluated the anti-tumor activity and mechanism of action of caffeine and anti-PD1 mAb combination therapy against carcinogen- and cell line-induced tumors. Our results demonstrate that combination therapy enhanced the anti-tumor activity and prolonged overall survival period against 3-MCA-induced tumors. In addition, combination therapy showed a significant anti-tumor activity against B16F10 melanoma tumors. We found that combination therapy showed additive increase in infiltration of CD4+ and CD8+ T lymphocytes into the B16F10 melanoma tumors. On the other hand, combination therapy showed significant decrease in infiltration of CD4+CD25+ T regulatory cells. We further investigated whether the observed anti-tumor effect of caffeine and anti-PD1 mAb combination therapy is mediated through the release of cytokines. We found that caffeine and anti-PD1 mAb combination therapy significantly increased intra-tumoral TNF-α and IFN-γ levels. Our work suggests that administration of caffeine and anti-PD1 mAb harness the therapeutic potential of effector T cells in vivo possibly due to combined blockade of PD1 and adenosine-A2A receptor pathway. This study provides the scientific basis for testing combination regimens of caffeine and anti-PD1 mAbs for sustained tumor control in cancer patients.

MoS2-Modified Curcumin Nanostructures: The Novel Theranostic Hybrid Having Potent Antibacterial and Antibiofilm Activities against Multidrug-Resistant Hypervirulent Klebsiella pneumoniae.

The recent emergence of hypervirulent clinical variants of Klebsiella pneumoniae (hvKP) causing community-acquired, invasive, metastatic, life-threatening infections of lungs, pleura, prostate, bones, joints, kidneys, spleen, muscles, soft-tissues, skin, eyes, central nervous system (CNS) including extrahepatic abscesses, and primary bacteremia even in healthy individuals has posed stern challenges before the existing treatment modalities. There is therefore an urgent need to look for specific and effective therapeutic alternatives against the said bacterial infection or recurrence. A new type of MoS2-modified curcumin nanostructure has been developed and evaluated as a potential alternative for the treatment of multidrug-resistant isolates. The curcumin quantum particles have been fabricated with MoS2 via a seed-mediated hydrothermal method, and the resulting MoS2-modified curcumin nanostructures (MQCs) have been subsequently tested for their antibacterial and antibiofilm properties against hypervirulent multidrug-resistant Klebsiella pneumoniae isolates. In the present study, we found MQCs inhibiting the bacterial growth at a minimal concentration of 0.0156 µg/mL, while complete inhibition of bacterial growth was evinced at concentration 0.125 µg/mL. Besides, we also investigated their biocompatibility both in vitro and in vivo. MQCs were found to be nontoxic to the SiHa cells at a dose as high as 1024 µg/mL on the basis of the tested adhesion, spreading of the cells, and also on the various serological, biochemical, and histological investigations of the vital organs and blood of the Charles Foster Rat. These results suggest that MQCs have potent antimicrobial activities against hvKP and other drug resistant isolates and therefore may be used as broad spectrum antibacterial and antibiofilm agents.

Caffeine-enhanced anti-tumor immune response through decreased expression of PD1 on infiltrated cytotoxic T lymphocytes.

Caffeine (1,3,7-trimethylxanthine) is a naturally occurring, habitually consumed food constituent throughout the world. Prospective cohort studies revealed that caffeine consumption reduces the relative risk of various cancers. Avoiding immune destruction is one of the emerging hallmarks of cancer. One of the immunosuppressive pathways that contribute in avoiding immune destruction by cancer cells is adenosine-A2A receptor pathway. Based on prospective epidemiological and mechanistic preclinical studies of caffeine and its predominant antagonistic effect on A2A receptor, we aimed to investigate the effect of caffeine on T cell infiltration into the tumor and expression of PD-1 receptor on T lymphocytes during tumor initiation and progression in a carcinogen-induced tumor model. Our results demonstrate that caffeine treatment significantly lowered tumor incidence and tumor growth rate. We found that the total T-lymphocyte infiltration and CD8+ T lymphocyte infiltration was significantly increased in caffeine-treated groups. On the other hand, the infiltration of CD4+CD25+ regulatory T lymphocyte was significantly decreased in caffeine-treated groups. In addition, the PD-1 expression on CD8+ T lymphocytes and CD4+CD25+ regulatory T lymphocytes was significantly reduced in caffeine-treated groups. We further investigated whether the observed anti-tumor effect of caffeine is mediated through the release of cytokines. We found that TNF-α and IFN-γ levels were significantly higher in caffeine-treated groups. The findings of the present study unraveled the immune-related mechanisms behind the caffeinated coffee consumption and lower tumor incidence in humans. In conclusion, the blockade of adenosine pathway by caffeine may constitute an effective means to enhance anti-tumor immune response.

Classification of Clinical Isolates of Klebsiella pneumoniae Based on Their in vitro Biofilm Forming Capabilities and Elucidation of the Biofilm Matrix Chemistry With Special Reference to the Protein Content.

Klebsiella pneumoniae is a human pathogen, capable of forming biofilms on abiotic and biotic surfaces. The limitations of the therapeutic options against Klebsiella pneumoniae is actually due to its innate capabilities to form biofilm and harboring determinants of multidrug resistance. We utilized a newer approach for classification of biofilm producing Klebsiella pneumoniae isolates and subsequently we evaluated the chemistry of its slime, more accurately its biofilm. We extracted and determined the amount of polysaccharides and proteins from representative bacterial biofilms. The spatial distribution of sugars and proteins were then investigated in the biofilm matrix using confocal laser scanning microscopy (CLSM). Thereafter, the extracted matrix components were subjected to sophisticated analysis incorporating Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, one-dimensional gel-based electrophoresis (SDS-PAGE), high performance liquid chromatography (HPLC), and MALDI MS/MS analysis. Besides, the quantification of its total proteins, total sugars, uronates, total acetyl content was also done. Results suggest sugars are not the only/major constituent of its biofilms. The proteins were harvested and subjected to SDS-PAGE which revealed various common and unique protein bands. The common band was excised and analyzed by HPLC. MALDI MS/MS results of this common protein band indicated the presence of different proteins within the biofilm. The 55 different proteins were identified including both cytosolic and membrane proteins. About 22 proteins were related to protein synthesis and processing while 15 proteins were identified related to virulence. Similarly, proteins related to energy and metabolism were 8 and those related to capsule and cell wall synthesis were 4. These results will improve our understanding of Klebsiella biofilm composition and will further help us design better strategies for controlling its biofilm such as techniques focused on weakening/targeting certain portions of the slime which is the most common building block of the biofilm matrix.

Ascorbic acid therapy: A potential strategy against comorbid depression-like behavior in streptozotocin-nicotinamide-induced diabetic rats.

This study examined the potency and efficacy of ascorbic acid (AA) in the management of depression-like behavior in diabetic rats. Diabetes mellitus was induced by single intraperitoneal injections of nicotinamide (120 mg/kg) and streptozotocin (65 mg/kg) administered 15 min apart. Diabetic (blood glucose ≥250 mg/dL) rats were subjected to intermittent foot-shocks to induce comorbid depression. Seven groups of diabetes comorbid depressed rats received vehicle (1 mL/kg) or AA (10, 25, 50, 100, 200, or 400 mg/kg) orally for eleven days. Three control groups namely- nondiabetic, diabetic, and depressed rats received the vehicles only. The potency (ED50) and efficacy (Emax) of AA against immobility period, hypercorticosteronemia, adrenal hyperplasia, hyperglycemia, hypoinsulinemia, oxidative stress, and inflammatory response were estimated. AA administration caused a dose-dependent decrease (P < 0.05) in immobility period with maximum inhibition of 69% (efficacy) at 200 mg/kg and ED50 of 14 mg/kg (potency). AA at 200 mg/kg produced the maximal reduction in hypercorticosteronemia (55.1%) and adrenal hyperplasia (52.6%) with ED50 of 9.8 and 14.4 mg/kg, respectively. AA at 400 mg/kg produced the maximal reduction in hyperglycemia (35.5%), hypoinsulinemia (32.7%), and lipid peroxidation (82%) with ED50 of 18.6, 13.7, and 20.7 mg/kg, respectively. Moreover, AA at 400 mg/kg produced the maximal increase in SOD content (83%), CAT activity (77.9%), and IL-10 level (63%) with ED50 of 21.5, 21, and 21 mg/kg, respectively. In conclusion, the present results suggest that AA has therapeutic potential against diabetes comorbid depression but better regulation of hyperglycemia and hypoinsulinemia is required to achieve maximal benefits.

Correction: Quantum curcumin mediated inhibition of gingipains and mixed-biofilm of Porphyromonas gingivalis causing chronic periodontitis.

[This corrects the article DOI: 10.1039/C8RA08435A.].

Quantum curcumin mediated inhibition of gingipains and mixed-biofilm of Porphyromonas gingivalis causing chronic periodontitis.

Periodontitis is a biofilm-associated irreversible inflammation of the periodontal tissues. Reports suggest the role of Porphyromonas gingivalis specific Arg- and Lys-specific proteinases in the orchestration of the initiation and progression of periodontal diseases. These proteinases are precisely termed as gingipains R and K. Curcumin is an active polyphenol that is extracted from the rhizomes of Curcuma longa. However, the molecule curcumin owing to its high hydropathy index and poor stability has not been able to justify its role as frontline drug modality in the treatment of infectious and non-infectious diseases as claimed by several investigators. In the present study, at first, we synthesized and characterized quantum curcumin, and investigated its biocompatibility. This was subsequently followed by the evaluation of the role of quantum curcumin as an antimicrobial, anti-gingipains and antibiofilm agent against Porphyromonas gingivalis and select reference strains. We have successfully synthesized the quantum curcumin utilizing a top-down approach with the average size of 3.5 nm. Apart from its potent antimicrobial as well as antibiofilm properties, it also significantly inhibited the gingipains in a dose-dependent manner. At the minimal concentration of 17.826 µM, inhibition up to 98.7% and 89.4% was noted for gingipain R and K respectively. The data was also supported by the in silico docking experiments which revealed high exothermic enthalpies (-7.01 and -7.02 cal mol-1). Besides, the inhibition constant was found to be 7.24 µM and 7.1 µM against gingipains R and K respectively. The results suggest that quantum curcumin is a potential drug candidate which needs further clinical validation.