The effects of anti-TNF-α biologics on insulin resistance and insulin sensitivity in patients with rheumatoid arthritis: An update systematic review and meta-analysis.

BACKGROUND AND AIM: Increasing evidence demonstrates a link between the chronic inflammatory state in patients with rheumatoid arthritis (RA) and the development of insulin resistance. It is thought that anti-TNF-α biologic therapy may improve insulin sensitivity and ameliorate insulin resistance by the downregulation of inflammatory cytokines, however, pre-clinical and clinical studies have yielded conflicting results. A meta-analysis on this topic is necessary to summarize current evidence and generate hypotheses for future research. METHODS: Literature search was performed in four databases, namely PubMed, EMBASE, Scopus, and The Cochrane Library, from inception till April 9, 2023, querying studies reporting peripheral insulin resistance with and without anti-TNF-α use in patients with RA. Peripheral insulin resistance or sensitivity was quantified by the Homeostasis Model Assessment of Insulin Resistance (HOMA) index or the Quantitative Insulin Sensitivity Check Index (QUICKI) respectively. The difference in insulin resistance or sensitivity between the treatment and control group was calculated using standardized mean difference (SMD) for the purposes of the meta-analysis. RESULTS: Twelve articles were reviewed, with 10 longitudinal studies with a total of 297 patients included in the meta-analysis. The pooled standardized mean difference (SMD) from baseline HOMA was -0.82 (95% CI: -1.38 to -0.25) suggesting significant beneficial effects of anti-TNF-α therapy on insulin resistance. CONCLUSION: Current evidence supports the significant clinical efficacy of anti-TNF-α biologics in alleviating insulin resistance and improving insulin sensitivity in patients with active RA.

Survival Trends in Sorafenib for Advanced Hepatocellular Carcinoma: A Reconstructed Individual Patient Data Meta-Analysis of Randomized Trials.

Background: Emerging data suggest that outcomes for advanced hepatocellular carcinoma (HCC) treated with sorafenib may have improved over time. We aimed to provide robust, time-to-event estimates of survival outcomes for sorafenib in advanced HCC. Summary: In this systematic review and individual patient data meta-analysis of randomized-controlled trials (RCTs), we searched MEDLINE and Embase from inception till September 2022 for RCTs that provided data for overall survival (OS) and progression-free survival (PFS) for sorafenib monotherapy as first-line systemic therapy for advanced HCC. We performed a pooled analysis using reconstructed individual participant data from published Kaplan-Meier curves to obtain robust estimates for OS and PFS. Of 1,599 articles identified, 29 studies (5,525 patients) met the inclusion criteria. Overall, the median OS was 10.4 (95% CI: 9.6-11.4) months. Median OS increased over time, from 9.8 (95% CI: 8.8-10.7) months in studies before 2015 to 13.4 (95% CI: 11.03-15.24) months in studies from 2015 onwards (p < 0.001). OS did not differ by trial phase, geographical region, or study design. The overall median PFS was 4.4 (95% CI: 3.9-4.8) months, but PFS did not improve over time. Sensitivity analysis of studies from 2015 and onwards to account for the introduction of direct-acting antivirals determined that hepatitis C virus was associated with reduced mortality (p < 0.001). There was minimal heterogeneity in the estimates for OS (all I2 ≤ 33). Key Messages: Survival outcomes for sorafenib in advanced HCC have improved over time. These data have important implications for clinical trial design.

Complete alcohol abstinence increases the risk of NAFLD but not severity. A population analysis with transient elastography.

BACKGROUND & AIMS: As the global prevalence of non-alcoholic fatty liver disease (NAFLD) continues to rise, ubiquity of alcohol use has also prompted discussion regarding the potential interactions between the two. This study aims to examine the effects of modest alcohol consumption on the prevalence and complications of NAFLD in a multi-ethnic population. METHODS: This study analyses the 2017-2018 cycles of NHANES that examined liver fibrosis and steatosis with vibration controlled transient elastography. A coarsened exact matching was conducted to reduce confounding. Logistic regression was done with a multivariate model to assess the relationship between alcohol consumption (modest drinkers and non-drinkers) and risk of NAFLD and its complications. RESULTS: 2,067 individuals were found to have NAFLD and 284 NAFLD patients had a total history of alcohol abstinence. After coarsened exact matching, the prevalence of NAFLD was 49% (CI: 0.41 - 0.58) in non-drinkers and 33% (CI: 0.26 - 0.41) in modest drinkers. Non-drinkers had twice the odds of NAFLD compared to modest drinkers (OR: 1.99, CI: 1.22 - 3.22, p<.01) after adjustment for confounders. There were no significant differences in the odds of significant fibrosis, advance fibrosis, cirrhosis, cardiovascular disease and stroke between non-drinkers and modest drinkers. The odds of malignancy in non-drinkers were almost significantly less than modest drinkers (OR: 0.28, CI:0.08 - 1.02, p=.053). CONCLUSION: Interestingly, modest alcohol consumption is associated with decreased odds of NAFLD. Further investigations are required to examine the relationship between alcohol consumption and NAFLD and subsequently the potential impact on NAFLD management.

A Class Effect Network Meta-analysis of Lipid Modulation in Non-alcoholic Steatohepatitis for Dyslipidemia.

Background and Aims: Pharmaceutical therapy for NASH is associated with lipid modulation, but the consensus on drug treatment is limited and lacks comparative analysis of effectiveness. A network meta-analysis was conducted to compare NASH drug classes in lipid modulation. Methods: Online databases were searched for randomized controlled trails (RCTs) evaluating NASH treatments in biopsy-proven NASH patients. Treatments were classified into four groups: (1) inflammation, (2) energy, (3) bile acids, and (4) fibrosis based on the mechanism of action. A Bayesian network analysis was conducted with outcome measured by mean difference (MD) with credible intervals (Crl) and surface under the cumulative ranking curve (SUCRA). Results: Forty-four RCTs were included in the analysis. Bile acid modulating treatments (MD: 0.05, Crl: 0.03-0.07) were the best treatment for improvement in high-density lipid (HDL) cholesterol, followed by treatments modulating energy (MD: 0.03, Crl: 0.02-0.04) and fibrosis (MD: 0.01, Crl: -0.12 to 0.14) compared with placebo. The top three treatments for reduction in triglycerides were treatments modulating energy (MD: -0.46, Crl: -0.49 to -0.43), bile acids (MD: -0.22, Crl: -0.35 to -0.09), and inflammation (MD: -0.08, Crl: -0.13 to -0.03) compared with placebo. SUCRA found treatment modulating fibrosis (MD: -1.27, Crl: -1.76 to -0.79) was the best treatment for reduction in low-density lipid (LDL) cholesterol followed by treatment modulating inflammation (MD: -1.03, Crl: -1.09 to -0.97) and energy (MD: -0.37, Crl: -0.39 to -0.34) compared with placebo, but LDL cholesterol was worsened by treatments modulating bile acids. Conclusions: Network analysis comparing the class effects of dyslipidemia modulation in NASH found that treatment targets can include optimization of atherogenic dyslipidemia. Future studies are required to evaluate the cardiovascular outcomes.

Depression in non-alcoholic fatty liver disease is associated with an increased risk of complications and mortality.

Background and aims: The global prevalence of non-alcoholic fatty liver disease (NAFLD) is expected to rise continuously. Furthermore, emerging evidence has also shown the potential for concomitant depression in NAFLD. This study aims to examine the prevalence, risk factors, and adverse events of depression in NAFLD and evaluate whether treated depression can reverse the increased risks of adverse outcomes. Materials and methods: This study analyses the 2000-2018 cycles of NHANES that examined liver steatosis with fatty liver index (FLI). The relationship between NAFLD and depression was assessed with a generalized linear mix model and a sensitivity analysis was conducted in the no depression, treated depression, and untreated depression groups. Survival analysis was conducted with cox regression and fine gray sub-distribution model. Results: A total of 21,414 patients were included and 6,726 were diagnosed with NAFLD. The risk of depression in NAFLD was 12% higher compared to non-NAFLD individuals (RR: 1.12, CI: 1.00-1.26, p = 0.04). NAFLD individuals with depression were more likely to be older, females, Hispanics or Caucasians, diabetic, and have higher BMI. Individuals with depression have high risk for cardiovascular diseases (CVD) (RR: 1.40, CI: 1.25-1.58, p < 0.01), stroke (RR: 1.71, CI: 1.27-2.23, p < 0.01), all-cause mortality (HR: 1.50, CI: 1.25-1.81, p < 0.01), and cancer-related mortality (SHR: 1.43, CI: 1.14-1.80, p = 0.002) compared to NAFLD individuals without depression. The risk of CVD, stroke, all-cause mortality, and cancer-related mortality in NAFLD individuals with treated depression and depression with untreated treatment was higher compared to individuals without depression. Conclusion: This study shows that concomitant depression in NAFLD patients can increase the risk of adverse outcomes. Early screening of depression in high-risk individuals should be encouraged to improve the wellbeing of NAFLD patients.

Risk of Hepatocellular Carcinoma With Tenofovir vs Entecavir Treatment for Chronic Hepatitis B Virus: A Reconstructed Individual Patient Data Meta-analysis.

Importance: Conventional meta-analyses with aggregated study-level data have yielded conflicting results for the comparative effectiveness of tenofovir disoproxil fumarate vs entecavir in reducing hepatocellular carcinoma (HCC) risk among patients with chronic hepatitis B virus. Within-study heterogeneity, between-study heterogeneity, and the inability of conventional meta-analyses to capture time-to-event data were associated with these results. Objective: To perform a reconstructed individual patient data meta-analysis of high-quality propensity score-matched studies to provide robust estimates for comparative HCC risk between groups receiving tenofovir or entecavir. Data Sources: Medline and Embase databases were searched from inception to October 6, 2021. Study Selection: The initial search yielded 3435 articles. Fourteen studies that used propensity score matching to balance baseline characteristics were included in the final analysis. Data Extraction and Synthesis: The Preferred Reporting Items for Systematic Reviews and Meta-analyses guideline was followed. Individual patient data were reconstructed from Kaplan-Meier curves. Risk of HCC was evaluated using random-effects hazard ratios (HRs) via a shared-frailty model and a Cox proportional hazards model stratified by study group. Restricted mean survival time (RMST) analysis was conducted to account for varying estimated treatment effect across time. Main Outcomes and Measures: The comparative risk of HCC with tenofovir vs entecavir treatment. Results: From analysis of 14 studes with 24 269 patients (10 534 receiving tenofovir and 13 735 receiving entecavir; mean age, 49.86 [95% CI, 48.35-51.36] years; 65.05% [95% CI, 58.60%-71.00%] men), tenofovir was associated with decreased HCC incidence compared with entecavir (stratified Cox HR, 0.85 [95% CI, 0.76-0.94] at 5 years; P = .002). However, there was no significant difference in subanalysis of clinical cohort studies (stratified Cox HR, 0.92 [95% CI, 0.80-1.06] at 5 years; P = .24). Among administrative database studies, proportionality was violated, and HRs could not be obtained via Cox proporational hazards-based models. The mean time to HCC development in RMST analysis was 2.8 (95% CI, 1.8-3.7) weeks longer (P < .001) for tenofovir vs entecavir at 5 years. The RMST analyses for other subgroups revealed either insignificant or minimal differences (<3 weeks) in the mean time to HCC at 5 years. Conclusions and Relevance: In this meta-analysis, there was no clinically meaningful difference in the risk of HCC between patients who received entecavir and patients who received tenofovir. There was no difference between tenofovir and entecavir among clinical cohort studies, whereas the mean time to HCC development was less than 3 weeks longer for patients who received tenofovir vs those who received entecavir at year 5 among administrative database studies. The choice between tenofovir or entecavir should be decided based on patient convenience and tolerability.

Metabolic Associated Fatty Liver Disease Increases the Risk of Systemic Complications and Mortality. A Meta-Analysis and Systematic Review of 12 620 736 Individuals.

OBJECTIVE: The recent introduction of the term metabolic associated fatty liver disease (MAFLD) sought to reclassify nonalcoholic fatty liver disease (NAFLD). MAFLD is thought to improve the encapsulation of metabolic dysregulation. However, recent evidence has found significant differences between MAFLD and NAFLD, and prevailing knowledge has largely arisen from studies on NAFLD. Hence, we conducted a meta-analysis and systematic review of the outcomes associated with MAFLD. METHODS: MEDLINE and Embase databases were searched for articles relating to outcomes in MAFLD. Analysis was conducted in random effects with hazard ratios (HRs) to account for longitudinal risk assessment of mortality and systemic complications. RESULTS: A total of 554 articles were identified, of which 17 articles were included. MAFLD resulted in an increase in the overall mortality (HR, 1.24; confidence interval [CI], 1.13-1.34), cancer-related mortality (HR, 1.27; CI, 1.01-1.54), and cardiovascular disease mortality (HR, 1.28, 1.03-1.53; P = .04) compared with non-MAFLD. MAFLD also increases the risk of cardiovascular events (HR, 1.49; CI, 1.34-1.64; P < .01), stroke (HR, 1.55; CI, 1.37-1.73; P < .01), and chronic kidney disease (HR, 1.53; CI, 1.38-1.68). The presence of MAFLD was also associated with an increased risk of heart failure, obstructive sleep apnea, and malignancy. CONCLUSION: MAFLD can significantly elevate the risk of systemic diseases and mortality. The care of MAFLD thus requires interdisciplinary collaboration, and future clinical trials conducted on MAFLD should aim to reduce the incidence of end-organ damage aside from improving liver histology.

Curcumin-C3 Complexed with α-, ß-cyclodextrin Exhibits Antibacterial and Antioxidant Properties Suitable for Cancer Treatments.

BACKGROUND: The curcumin-C3 (cur-C3) complex obtained from Curcuma longa rhizome is a combination of three curcuminoids, namely, curcumin, dimethoxycurcumin, and bisdemethoxycurcumin. Cur and curcuminoids have been extensively researched for their wide range of therapeutic properties against inflammatory diseases, diabetes, and cancer. OBJECTIVE: In spite of their extensive medicinal properties, cur and curcuminoids have poor solubility and bioavailability due to their hydrophobicity. This limitation can be overcome by complexing cur-C3 with natural cyclic oligosaccharides, such as Cyclodextrin (CD). METHODS: In this study, cur-C3 and CD (α, ß) inclusion complexes (ICs) were prepared with different molar ratios and characterized by nuclear magnetic resonance, Fourier transform infrared spectroscopy, X-ray diffraction, and transmission electron microscopy. RESULTS: The cur-C3 cyclodextrin ICs showed an increased entrapment efficiency of 97.8% and improved antioxidant activity compared to cur and can be used as an antioxidant to reduce cancer-related oxidative stress. Additionally, α- CD ICs of curcumin-C3 caused an increase in growth inhibition of Staphylococcus aureus. CONCLUSION: Our findings suggest that both α- and ß-CDs are suitable carriers for cur-C3 and can be used as an effective treatment for cancer-associated oxidative stress and as a preventive treatment for nosocomial infections and pneumonia.

Phloretin suppresses metastasis by targeting protease and inhibits cancer stemness and angiogenesis in human cervical cancer cells.

BACKGROUND: Phloretin, a dihydrochalcone flavonoid, possesses anti-inflammatory activity and inhibits the growth of various cancers. However, the flavonoid's effect on cervical cancer metastasis and angiogenesis remains unknown. PURPOSE: In this study, we provide molecular evidence associated with the antimetastatic and antiangiogenic effects of phloretin. METHODS: In this study, the anti-invasive effect of phloretin (0-60 µM) in cervical cancer cells was evaluated using the Matrigel invasion assay, gelatin zymography, cell-matrix adhesion assay, wound healing assay, and Western blotting. Antiangiogenic potential of phloretin (0-100 µM) was assessed by the Matrigel tube formation assay. The in vivo antitumor effect of phloretin (10 or 20 mg/kg) was fed by oral gavage and determined using subcutaneous inoculation and tail vein injection in immunodeficient nude mice. RESULTS: Phloretin (60 µM) showed marked suppression of invasion and migration through downregulation of matrix metalloproteinase (MMP)-2, MMP-3, and cathepsin S in human SiHa cervical cancer cells. Phloretin (60 µM) reversed the epithelial-mesenchymal transition induced by transforming growth factor-ß1 and downregulated mesenchymal markers, such as fibronectin, vimentin, and RhoA. Phloretin (100 µM) treatment significantly inhibited the aldehyde dehydrogenase 1 activity of SiHa cells, reduced the self-renewal properties and stemness signatures of CD44 and Sox-2 in sphere-forming cervical cancer-derived tumor-initiating cells, and inhibited the invasion, MMP-2 activity, and tube formation capacity of human umbilical vein endothelial cells. The ability of phloretin (20 mg/kg) to suppress lung metastasis and tumor growth in SiHa cells was evidenced by tail vein injection and subcutaneous inoculation in a tumor xenograft model. CONCLUSION: In summary, the findings indicate that phloretin inhibits the metastatic and angiogenic abilities and cancer stemness of SiHa cells, thereby suggesting that this flavonoid is a promising therapeutic agent for the treatment of human cervical cancer cells.

Multilayer photodynamic therapy for highly effective and safe cancer treatment.

Recent efforts to develop tumor-targeted photodynamic therapy (PDT) photosensitizers (PSs) have greatly advanced the potential of PDT in cancer therapy, although complete eradication of tumor cells by PDT alone remains challenging. As a way to improve PDT efficacy, we report a new combinatory PDT therapy technique that specifically targets multilayers of cells. Simply mixing different PDT PSs, even those that target distinct receptors (this may still lead to similar cell-killing pathways), may not achieve ideal therapeutic outcomes. Instead, significantly improved outcomes likely require synergistic therapies that target various cellular pathways. In this study, we target two proteins upregulated in cancers: the cannabinoid CB2 receptor (CB2R, a G-protein coupled receptor) and translocator protein (TSPO, a mitochondria membrane receptor). We found that the CB2R-targeted PS, IR700DX-mbc94, triggered necrotic cell death upon light irradiation, whereas PDT with the TSPO-targeted IR700DX-6T agent led to apoptotic cell death. Both PSs significantly inhibited tumor growth in vivo in a target-specific manner. As expected, the combined CB2R- and TSPO-PDT resulted in enhanced cell killing efficacy and tumor inhibition with lower drug dose. The median survival time of animals with multilayer PDT treatment was extended by as much as 2.8-fold over single PDT treatment. Overall, multilayer PDT provides new opportunities to treat cancers with high efficacy and low side effects. STATEMENT OF SIGNIFICANCE: Photodynamic therapy (PDT) is increasingly used as a minimally invasive, controllable and effective therapeutic procedure for cancer treatment. However, complete eradication of tumor cells by PDT alone remains challenging. In this study, we investigate the potential of multilayer PDT in cancer treatment with high efficacy and low side effects. Through PDT targeting two cancer biomarkers located at distinct subcellular localizations, remarkable synergistic effects in cancer cell killing and tumor inhibition were observed in both in vitro and in vivo experiments. This strategy may be widely applied to treat various cancer types by using strategically designed PDT photosensitizers that target corresponding upregulated receptors at tactical subcellular localization.

Tumor mitochondria-targeted photodynamic therapy with a translocator protein (TSPO)-specific photosensitizer.

Photodynamic therapy (PDT) has been proven to be a minimally invasive and effective therapeutic strategy for cancer treatment. It can be used alone or as a complement to conventional cancer treatments, such as surgical debulking and chemotherapy. The mitochondrion is an attractive target for developing novel PDT agents, as it produces energy for cells and regulates apoptosis. Current strategy of mitochondria targeting is mainly focused on utilizing cationic photosensitizers that bind to the negatively charged mitochondria membrane. However, such an approach is lack of selectivity of tumor cells. To minimize the damage on healthy tissues and improve therapeutic efficacy, an alternative targeting strategy with high tumor specificity is in critical need. Herein, we report a tumor mitochondria-specific PDT agent, IR700DX-6T, which targets the 18kDa mitochondrial translocator protein (TSPO). IR700DX-6T induced apoptotic cell death in TSPO-positive breast cancer cells (MDA-MB-231) but not TSPO-negative breast cancer cells (MCF-7). In vivo PDT study suggested that IR700DX-6T-mediated PDT significantly inhibited the growth of MDA-MB-231 tumors in a target-specific manner. These combined data suggest that this new TSPO-targeted photosensitizer has great potential in cancer treatment. STATEMENT OF SIGNIFICANCE: Photodynamic therapy (PDT) is an effective and minimally invasive therapeutic technique for treating cancers. Mitochondrion is an attractive target for developing novel PDT agents, as it produces energy to cells and regulates apoptosis. Current mitochondria targeted photosensitizers (PSs) are based on cationic molecules, which interact with the negatively charged mitochondria membrane. However, such PSs are not specific for cancerous cells, which may result in unwanted side effects. In this study, we developed a tumor mitochondria-targeted PS, IR700DX-6T, which binds to translocator protein (TSPO). This agent effectively induced apoptosis in TSPO-positive cancer cells and significantly inhibited tumor growth in TSPO-positive tumor-bearing mice. These combined data suggest that IR700DX-6T could become a powerful tool in the treatment of multiple cancers that upregulate TSPO.

In vivo inflammation imaging using a CB2R-targeted near infrared fluorescent probe.

Chronic inflammation is considered as a critical cause of a host of disorders, such as cancer, rheumatoid arthritis, atherosclerosis, and neurodegenerative diseases, although the exact mechanism is yet to be explored. Imaging tools that can specifically target inflammation are therefore important to help reveal the role of inflammation in disease progression, and allows for developing new therapeutic strategies to ultimately improve patient care. The purpose of this study was to develop a new in vivo inflammation imaging approach by targeting the cannabinoid receptor type 2 (CB2R), an emerging inflammation biomarker, using a unique near infrared (NIR) fluorescent probe. Herein, we report the first in vivo CB2R-targeted NIR inflammation imaging study using a synthetic fluorescent probe developed in our laboratory, NIR760-mbc94. In vitro binding assay and fluorescence microscopy study indicate NIR760-mbc94 specifically binds towards CB2R in mouse RAW264.7 macrophage cells. Furthermore, in vivo imaging was performed using a Complete Freund's Adjuvant (CFA)-induced inflammation mouse model. NIR760-mbc94 successfully identified inflamed tissues and the probe uptake was blocked by a CB2R ligand, SR144528. Additionally, immunofluorescence staining in cryosectioned tissues validated the NIR760-mbc94 uptake in inflamed tissues. In conclusion, this study reports the first in vivo CB2R-targeted inflammation imaging using an NIR fluorescent probe. Specific targeting of NIR760-mbc94 has been demonstrated in macrophage cells, as well as a CFA-induced inflammation mouse model. The combined evidence indicates that NIR760-mbc94 is a promising inflammation imaging probe. Moreover, in vivo CB2R-targeted fluorescence imaging may have potential in the study of inflammation-related diseases.

A novel near-infrared fluorescence imaging probe that preferentially binds to cannabinoid receptors CB2R over CB1R.

The type 2 cannabinoid receptors (CB2R) have gained much attention recently due to their important regulatory role in a host of pathophysiological processes. However, the exact biological function of CB2R and how this function might change depending on disease progression remains unclear and could be better studied with highly sensitive and selective imaging tools for identifying the receptors. Here we report the first near infrared fluorescence imaging probe (NIR760-XLP6) that binds preferentially to CB2R over the type 1 cannabinoid receptors (CB1R). The selectivity of the probe was demonstrated by fluorescence microscopy using DBT-CB2 and DBT-CB1 cells. Furthermore, in mouse tumor models, NIR760-XLP6 showed significantly higher uptake in DBT-CB2 than that in DBT-CB1 tumors. These findings indicate that NIR760-XLP6 is a promising imaging tool for the study of CB2R regulation.

Molecular imaging of human tumor cells that naturally overexpress type 2 cannabinoid receptors using a quinolone-based near-infrared fluorescent probe.

Cannabinoid CB2 receptors (CB2R) hold promise as therapeutic targets for treating diverse diseases, such as cancers, neurodegenerative diseases, pain, inflammation, osteoporosis, psychiatric disorders, addiction, and immune disorders. However, the fundamental role of CB2R in the regulation of diseases remains unclear, largely due to a lack of reliable imaging tools for the receptors. The goal of this study was to develop a CB2R-targeted molecular imaging probe and evaluate the specificity of the probe using human tumor cells that naturally overexpress CB2R. To synthesize the CB2R-targeted probe (NIR760-Q), a conjugable CB2R ligand based on the quinolone structure was first prepared, followed by bioconjugation with a near-infrared (NIR) fluorescent dye, NIR760. In vitro fluorescence imaging and competitive binding studies showed higher uptake of NIR760-Q than free NIR760 dye in Jurkat human acute T-lymphoblastic leukemia cells. In addition, the high uptake of NIR760-Q was significantly inhibited by the blocking agent, 4-quinolone-3-carboxamide, indicating specific binding of NIR760-Q to the target receptors. These results indicate that the NIR760-Q has potential in diagnostic imaging of CB2R positive cancers and elucidating the role of CB2R in the regulation of disease progression.

Cannabinoid CB2 receptor as a new phototherapy target for the inhibition of tumor growth.

The success of targeted cancer therapy largely relies upon the selection of target and the development of efficient therapeutic agents that specifically bind to the target. In the current study, we chose a cannabinoid CB2 receptor (CB2R) as a new target and used a CB2R-targeted photosensitizer, IR700DX-mbc94, for phototherapy treatment. IR700DX-mbc94 was prepared by conjugating a photosensitizer, IR700DX, to mbc94, whose binding specificity to CB2R has been previously demonstrated. We found that phototherapy treatment using IR700DX-mbc94 greatly inhibited the growth of CB2R positive tumors but not CB2R negative tumors. In addition, phototherapy treatment with nontargeted IR700DX did not show significant therapeutic effect. Similarly, treatment with IR700DX-mbc94 without light irradiation or light irradiation without the photosensitizer showed no tumor-inhibitory effect. Taken together, IR700DX-mbc94 is a promising phototherapy agent with high target-specificity. Moreover, CB2R appears to have great potential as a phototherapeutic target for cancer treatment.

Synthesis and optical properties of water-soluble biperylene-based dendrimers.

We report the synthesis and photophysical properties of three biperylene-based dendrimers, which show red fluorescence in water. A fluorescence microscopy study demonstrated uptake of biperylene-based dendrimers in living cells. Our results indicate that these biperylene-based dendrimers are promising candidates in fluorescence imaging applications with the potential as therapeutic carriers.

Target-selective phototherapy using a ligand-based photosensitizer for type 2 cannabinoid receptor.

Phototherapy is a powerful, noninvasive approach for cancer treatment, with several agents currently in clinical use. Despite the progress and promise, most current phototherapy agents have serious side effects as they can lead to damage to healthy tissue, even when the photosensitizers are fused to targeting molecules due to nonspecific light activation of the unbound photosensitizer. To overcome these limitations, we developed a phototherapy agent that combines a functional ligand and a near infrared phthalocyanine dye. Our target is type 2 cannabinoid receptor (CB2R), considered an attractive therapeutic target for phototherapy given it is overexpressed by many types of cancers that are located at a surface or can be reached by an endoscope. We show that our CB2R-targeted phototherapy agent, IR700DX-mbc94, is specific for CB2R and effective only when bound to the target receptor. Overall, this opens up the opportunity for development of an alternative treatment option for CB2R-positive cancers.

Targeted zwitterionic near infrared fluorescent probe for improved imaging of type 2 cannabinoid receptors.

Recent studies indicate that the type 2 cannabinoid receptors (CB2R) have become an attractive target for treating a variety of pathologies, including cancers, neurodegenerative diseases, inflammation, pain, osteoporosis, immunological disorders and drug abuse. In addition, it appears that many of these diseases have up-regulated CB2R expression. However, the precise role of CB2R in the regulation of diseases remains unclear. The ability to specifically image CB2R would contribute to develop reliable CB2R-based therapeutic approaches with a better understanding of the mechanism of CB2R action in these diseases. We developed a CB2R-targeted zwitterionic near-infrared (NIR) fluorescent probe, ZW760-mbc94. When compared with a previously reported CB2R probe (NIR760-mbc94) with the same targeting moiety but a charged NIR fluorescent dye, ZW760-mbc94 showed improved binding specificity in vitro and ex vivo. Overall, ZW760-mbc94 appears to have great potential as a CB2R-targeted contrast agent.

Perfluorocarbon nanoemulsions with fluorescent, colloidal and magnetic properties.

Bimodal imaging agents that combine magnetic resonance imaging (MRI) and nearinfrared (NIR) imaging formulated as nanoemulsions became increasingly popular for imaging inflammation in vivo. Quality of in vivo imaging using nanoemulsions is directly dependent on their integrity and stability. Here we report the design of nanoemulsions for bimodal imaging, where both photostability and colloidal stability are equally addressed. A highly chemically and photo stable quaterrylenediimide dye was introduced into perfluoro-15-crown-5 ether (PCE) nanoemulsions. The nanoemulsions were prepared with PCE and Miglyol 812N mixed at 1:1 v/v ratio as internal phase stabilized by non-ionic surfactants. Data shows exceptional colloidal stability demonstrated as unchanged droplet size (~130 nm) and polydispersity (<0.15) after 182 days follow up at both 4 and 25 °C. Nanoemulsions also sustained the exposure to mechanical and temperature stress, and prolonged exposure to light without changes in droplet size, (19)F signal or fluorescence signal. No toxicity was observed in vitro in model inflammatory cells upon 24 h exposure while confocal microscopy showed that nanoemulsions droplets accumulated in the cytoplasm. Overall, our data demonstrates that design of bimodal imaging agents requires consideration of stability of each imaging component and that of the nanosystem as a whole to achieve excellent imaging performance.

In vivo type 2 cannabinoid receptor-targeted tumor optical imaging using a near infrared fluorescent probe.

The type 2 cannabinoid receptor (CB2R) plays a vital role in carcinogenesis and progression and is emerging as a therapeutic target for cancers. However, the exact role of CB2R in cancer progression and therapy remains unclear. This has driven the increasing efforts to study CB2R and cancers using molecular imaging tools. In addition, many types of cancers overexpress CB2R, and the expression levels of CB2R appear to be associated with tumor aggressiveness. Such upregulation of the receptor in cancer cells provides opportunities for CB2R-targeted imaging with high contrast and for therapy with low side effects. In the present study, we report the first in vivo tumor-targeted optical imaging using a novel CB2R-targeted near-infrared probe. In vitro cell fluorescent imaging and a competitive binding assay indicated specific binding of NIR760-mbc94 to CB2R in CB2-mid delayed brain tumor (DBT) cells. NIR760-mbc94 also preferentially labeled CB2-mid DBT tumors in vivo, with a 3.7-fold tumor-to-normal contrast enhancement at 72 h postinjection, whereas the fluorescence signal from the tumors of the mice treated with NIR760 free dye was nearly at the background level at the same time point. SR144528, a CB2R competitor, significantly inhibited tumor uptake of NIR760-mbc94, indicating that NIR760-mbc94 binds to CB2R specifically. In summary, NIR760-mbc94 specifically binds to CB2R in vitro and in vivo and appears to be a promising molecular tool that may have great potential for use in diagnostic imaging of CB2R-positive cancers and therapeutic monitoring as well as in elucidating the role of CB2R in cancer progression and therapy.