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Objective: Malignant pleural mesothelioma is a fatal disease and a clinical challenge, as few effective treatment modalities are available. Previous evidence links the gut microbiome to the host immunoreactivity to tumors. We thus evaluated the impact of a novel microbiome modulator compound (MMC) on the gut microbiota composition, tumor immune microenvironment, and cancer control in a model of malignant pleural mesothelioma., Methods: Age- and weight-matched immunocompetent (n = 23) or athymic BALB/c mice (n = 15) were randomly assigned to MMC or no treatment (control) groups. MMC (31 ppm) was administered through the drinking water 14 days before AB12 malignant mesothelioma cell inoculation into the pleural cavity. The impact of MMC on tumor growth, animal survival, tumor-infiltrating leucocytes, gut microbiome, and fecal metabolome was evaluated and compared with those of control animals., Results: The MMC delayed tumor growth and significantly prolonged the survival of immunocompetent animals ( P  = .0015) but not that of athymic mice. The improved tumor control in immunocompetent mice correlated with increased infiltration of CD3 + CD8 + GRZB + cytotoxic T lymphocytes in tumors. Gut microbiota analyses indicated an enrichment in producers of short chain fatty acids in MMC-treated animals. Finally, we observed a positive correlation between the level of fecal short chain fatty acids and abundance of tumor-infiltrating cytotoxic T cells in malignant pleural mesothelioma., Conclusions: MMC administration boosts antitumor immunity, which correlates with a change in gut microbiome and metabolome. MMC may represent a valuable treatment option to combine with immunotherapy in patients with cancer., Competing Interests: S.S. is co-founder and employee of Embion Technologies SA, Switzerland, which developed and provided the MMC compound. However, the results were shared with Embion only at the end of the study so as not to interfere with the conduct of the study and interpretation of results. All other authors reported no conflicts of interest. The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest., (© 2024 The Author(s).)

Objectives: Malignant pleural mesothelioma (MPM) is a deadly disease with limited treatment options. Approaches to enhance patient immunity against MPM have been tested but shown variable results. Previously, we have demonstrated interesting vascular modulating properties of low-dose photodynamic therapy (L-PDT) on MPM. Here, we hypothesized that L-PDT vascular modulation could favour immune cell extravasation in MPM and improve tumour control in combination with immune checkpoint inhibitors., Methods: First, we assessed the impact of L-PDT on vascular endothelial E-selectin expression, a key molecule for immune cell extravasation, in vitro and in a syngeneic murine model of MPM. Second, we characterized the tumour immune cell infiltrate by 15-colour flow cytometry analysis 2 and 7 days after L-PDT treatment of the murine MPM model. Third, we determined how L-PDT combined with immune checkpoint inhibitor anti-CTLA4 affected tumour growth in a murine MPM model., Results: L-PDT significantly enhanced E-selectin expression by endothelial cells in vitro and in vivo. This correlated with increased CD8+ T cells and activated antigen-presenting cells (CD11b+ dendritic cells and macrophages) infiltration in MPM. Also, compared to anti-CTLA4 that only affects tumour growth, the combination of L-PDT with anti-CTLA4 caused complete MPM regression in 37.5% of animals., Conclusions: L-PDT enhances E-selectin expression in the MPM endothelium, which favours immune infiltration of tumours. The combination of L-PDT with immune checkpoint inhibitor anti-CTLA4 allows best tumour control and regression., (© The Author(s) 2020. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Mutations in APC promote colorectal cancer (CRC) progression through uncontrolled WNT signaling. Patients with desmoplastic CRC have a significantly worse prognosis and do not benefit from chemotherapy, but the mechanisms underlying the differential responses of APC-mutant CRCs to chemotherapy are not well understood. We report that expression of the transcription factor prospero homeobox 1 (PROX1) was reduced in desmoplastic APC-mutant human CRCs. In genetic Apc-mutant mouse models, loss of Prox1 promoted the growth of desmoplastic, angiogenic, and immunologically silent tumors through derepression of Mmp14. Although chemotherapy inhibited Prox1-proficient tumors, it promoted further stromal activation, angiogenesis, and invasion in Prox1-deficient tumors. Blockade of vascular endothelial growth factor A (VEGFA) and angiopoietin-2 (ANGPT2) combined with CD40 agonistic antibodies promoted antiangiogenic and immunostimulatory reprogramming of Prox1-deficient tumors, destroyed tumor fibrosis, and unleashed T cell-mediated killing of cancer cells. These results pinpoint the mechanistic basis of chemotherapy-induced hyperprogression and illustrate a therapeutic strategy for chemoresistant and desmoplastic CRCs.

Vascular-targeted low-dose photodynamic therapy (L-PDT) was shown to improve chemotherapy distribution in malignant pleural tumors such as malignant pleural mesothelioma (MPM). However, the mechanisms triggered by L-PDT on the tumor vasculature are still debated. In pericyte and endothelial cell co-cultures, we show that pericytes exhibit enhanced sensitivity towards L-PDT compared to endothelial cells, displaying actin stress fibers and cellular contraction via Rho/ROCK kinase signaling myosin light chain and focal adhesion kinase phosphorylation (MLC-P, FAK-P). We then confirm, in two separate MPM models, in mice the phosphorylation of the MLC in pericytes specifically following L-PDT. Furthermore, while L-PDT does not affect tumor vascular density or diameter, we show that it enhances tumor vascular pericyte coverage, leads to a drop in tumor interstitial fluid pressure and enhances the transport of FITC-dextran throughout tumors. In conclusion, L-PDT has the potential to stabilize the tumor vascular bed which improves vascular transport. The mechanism described in the present study may help translate and optimize this approach in patients. Lasers Surg. Med. 51:550-561, 2019. © 2019 Wiley Periodicals, Inc., (© 2019 Wiley Periodicals, Inc.)

Human pleural mesothelioma is an incurable and chemoresistant cancer. Using a nude mouse xenograft model of human pleural mesothelioma, we show that RAPTA-T, a compound undergoing preclinical evaluation, enhances tumor vascular function by decreasing blood vessel tortuosity and dilation, while increasing the coverage of endothelial cells by pericytes and vessel perfusion within tumors. This in turn significantly reduces the interstitial fluid pressure and increases oxygenation in the tumor. Consequently, RAPTA-T pre-treatment followed by the application of cisplatin or liposomal cisplatin (Lipoplatin) leads to increased levels of the cytotoxin in the tumor and enhanced mesothelioma growth inhibition. We demonstrate that the vascular changes induced by RAPTA-T are related, in part, to the inhibition of poly-(ADP-ribose) polymerase 1 (PARP-1) which is associated to tumor vascular stabilization. These findings suggest novel therapeutic implications for RAPTA-T to create conditions for superior drug uptake and efficacy of approved cytotoxic anti-cancer drugs in malignant pleural mesothelioma and potentially other chemoresistant tumors.

Background: Low-dose photodynamic therapy PDT (photoinduction) can modulate tumor vessels and enhance the uptake of liposomal cisplatin (Lipoplatin®) in pleural malignancies. However, the photo-induction conditions must be tightly controlled as overtreatment shuts down tumor vessels and enhances normal tissue drug uptake., Material and Methods: In a pleural sarcoma and adenocarcinoma rat model (n = 12/group), we applied photoinduction (0.0625 mg/kg Visudyne®, 10 J/cm 2 ) followed by intravenous Lipoplatin® (5 mg/kg) administration. Tumor and normal tissue IFP were assessed before and up to 1 hour following photoinduction. Lipoplatin® uptake was determined 60 minutes following photoinduction. We then treated the pleura of tumor-free minipigs with high dose photodynamic therapy (PDT) (0.0625 mg/kg Visudyne®, 30 J/cm 2 , n = 5) followed by Lipoplatin (5 mg/kg) administration., Results: In rodents, photoinduction resulted in a significant decrease of IFP (P < 0.05) in both tumor types but not in the surrounding normal lung, equally exposed to light. Also, photoinduction resulted in a significant increase of Lipoplatin® uptake in both tumor types (P < 0.05) but not in normal lung. Tumor IFP variation and Lipoplatin® uptake fitted an inverted parabola. In minipigs, high dose photodynamic treatment resulted in pleural IFP increase of some animals which predicted higher Lipoplatin® uptake levels., Conclusion: Normal and tumor vasculatures react differently to PDT. Continuous IFP monitoring in normal and tumor tissues is a promising biomarker of vessel photoinduction. Moderate drop in tumor with no change in normal tissue IFP are predictive of specific Lipoplatin® uptake by cancer following PDT. Lasers Surg. Med. 49:773-780, 2017. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

Uncontrolled activation of Rho signaling by RhoGEFs, in particular AKAP13 (Lbc) and its close homologs, is implicated in a number of human tumors with poor prognosis and resistance to therapy. Structure predictions and alanine scanning mutagenesis of Lbc identified a circumscribed hot region for RhoA recognition and activation. Virtual screening targeting that region led to the discovery of an inhibitor of Lbc-RhoA interaction inside cells. By interacting with the DH domain, the compound inhibits the catalytic activity of Lbc, halts cellular responses to activation of oncogenic Lbc pathways, and reverses a number of prostate cancer cell phenotypes such as proliferation, migration, and invasiveness. This study provides insights into the structural determinants of Lbc-RhoA recognition. This is a successful example of structure-based discovery of a small protein-protein interaction inhibitor able to halt oncogenic Rho signaling in cancer cells with therapeutic implications., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Objective: Phthalates and bisphenol A (BPA) are ubiquitous environmental toxicants, present in high concentrations in numerous consumer products. We hypothesized that maternal exposure to phthalates and BPA in pregnancy is associated with shortened gestation., Methods: Urinary phthalate and BPA metabolites from 72 pregnant women were measured at the last obstetric clinic visit prior to delivery. Using linear regression models, we estimated the change in gestational age associated with each interquartile range (IQR) increase in phthalate and BPA metabolite concentration., Results: IQR increases in urinary mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and BPA concentrations were associated with 4.2 and 1.1 d decreases in gestation, respectively. When stratified by gender, these alterations were found only in male infants., Conclusions: We conclude that MEHHP and BPA (free + glucuronide) are associated with reductions in gestation, with effects observed only in males. Our findings are consistent with the idea that these agents induce gender-specific alterations in signaling via PPAR-γ transcription factor, androgen precursors and/or inflammatory mediators during the initiation of labor.

In response to stress or injury the heart undergoes an adverse remodeling process associated with cardiomyocyte hypertrophy and fibrosis. Transformation of cardiac fibroblasts to myofibroblasts is a crucial event initiating the fibrotic process. Cardiac myofibroblasts invade the myocardium and secrete excess amounts of extracellular matrix proteins, which cause myocardial stiffening, cardiac dysfunctions and progression to heart failure. While several studies indicate that the small GTPase RhoA can promote profibrotic responses, the exchange factors that modulate its activity in cardiac fibroblasts are yet to be identified. In the present study, we show that AKAP-Lbc, an A-kinase anchoring protein (AKAP) with an intrinsic Rho-specific guanine nucleotide exchange factor (GEF) activity, is critical for activating RhoA and transducing profibrotic signals downstream of type I angiotensin II receptors (AT1Rs) in cardiac fibroblasts. In particular, our results indicate that suppression of AKAP-Lbc expression by infecting adult rat ventricular fibroblasts with lentiviruses encoding AKAP-Lbc specific short hairpin (sh) RNAs strongly reduces the ability of angiotensin II to promote RhoA activation, differentiation of cardiac fibroblasts to myofibroblasts, collagen deposition as well as myofibroblast migration. Interestingly, AT1Rs promote AKAP-Lbc activation via a pathway that requires the α subunit of the heterotrimeric G protein G12. These findings identify AKAP-Lbc as a key Rho-guanine nucleotide exchange factor modulating profibrotic responses in cardiac fibroblasts., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In response to stress or injury the heart undergoes a pathological remodeling process, associated with hypertrophy, cardiomyocyte death and fibrosis, that ultimately causes cardiac dysfunction and heart failure. It has become increasingly clear that signaling events associated with these pathological cardiac remodeling events are regulated by scaffolding and anchoring proteins, which allow coordination of pathological signals in space and time. A-kinase anchoring proteins (AKAPs) constitute a family of functionally related proteins that organize multiprotein signaling complexes that tether the cAMP-dependent protein kinase (PKA) as well as other signaling enzymes to ensure integration and processing of multiple signaling pathways. This review will discuss the role of AKAPs in the cardiac response to stress. Particular emphasis will be given to the adaptative process associated with cardiac hypoxia as well as the remodeling events linked to cardiac hypertrophy and heart failure. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Cardiac Pathways of Differentiation, Metabolism and Contraction., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The mitogen-activated protein kinases (MAPKs) pathways are highly organized signaling systems that transduce extracellular signals into a variety of intracellular responses. In this context, it is currently poorly understood how kinases constituting these signaling cascades are assembled and activated in response to receptor stimulation to generate specific cellular responses. Here, we show that AKAP-Lbc, an A-kinase anchoring protein (AKAP) with an intrinsic Rho-specific guanine nucleotide exchange factor activity, is critically involved in the activation of the p38α MAPK downstream of α(1b)-adrenergic receptors (α(1b)-ARs). Our results indicate that AKAP-Lbc can assemble a novel transduction complex containing the RhoA effector PKNα, MLTK, MKK3, and p38α, which integrates signals from α(1b)-ARs to promote RhoA-dependent activation of p38α. In particular, silencing of AKAP-Lbc expression or disrupting the formation of the AKAP-Lbc·p38α signaling complex specifically reduces α(1)-AR-mediated p38α activation without affecting receptor-mediated activation of other MAPK pathways. These findings provide a novel mechanistic hypothesis explaining how assembly of macromolecular complexes can specify MAPK signaling downstream of α(1)-ARs.

AKAP-Lbc is a member of the A-kinase anchoring protein (AKAP) family that has been recently associated with the development of pathologies, such as cardiac hypertrophy and cancer. We have previously demonstrated that, at the molecular level, AKAP-Lbc functions as a guanine nucleotide exchange factor (GEF) that promotes the specific activation of RhoA. In the present study, we identified the ubiquitin-like protein LC3 as a novel regulatory protein interacting with AKAP-Lbc. Mutagenesis studies revealed that LC3, through its NH(2)-terminal alpha-helical domain, interacts with two binding sites located within the NH(2)-terminal regulatory region of AKAP-Lbc. Interestingly, LC3 overexpression strongly reduced the ability of AKAP-Lbc to interact with RhoA, profoundly impairing the Rho-GEF activity of the anchoring protein and, as a consequence, its ability to promote cytoskeletal rearrangements associated with the formation of actin stress fibers. Moreover, AKAP-Lbc mutants that fail to interact with LC3 show a higher basal Rho-GEF activity as compared with the wild type protein and become refractory to the inhibitory effect of LC3. This suggests that LC3 binding maintains AKAP-Lbc in an inactive state that displays a reduced ability to promote downstream signaling. Collectively, these findings provide evidence for a previously uncharacterized role of LC3 in the regulation of Rho signaling and in the reorganization of the actin cytoskeleton.

Although fetal breathing movements are required for normal lung development, there is uncertainty concerning the specific effect of absent fetal breathing movements on pulmonary cell maturation. We set out to evaluate pulmonary development in a genetically defined mouse model, the myogenin null mouse, in which there is a lack of normal skeletal muscle fibers and thus skeletal muscle movements are absent in utero. Significant decreases were observed in lung:body weight ratio and lung total DNA at embryonic days (E)14, E17, and E20. Reverse transcriptase/polymerase chain reaction, in situ immunofluorescence, and electron microscopy revealed early lung cell differentiation in both null and wild-type lungs as early as E14. However at E14, myogenin null lungs had decreased 5'-bromo-2-deoxyuridine incorporation compared with that of wild-type littermates, whereas at E17 and E20, increased Bax immunolabeling and terminal deoxyribonucleotidyl transferase-mediated dUTP-biotin nick-end labeling staining were detected in the myogenin null mice but not in the wild-type littermates. These observations highlight the importance of skeletal muscle contractile activity in utero for normal lung organogenesis. Null mice lacking the muscle-specific transcription factor myogenin exhibit a secondary effect on lung development such that decreased lung cell proliferation and increased programmed cell death are associated with lung hypoplasia.

The myogenin gene encodes an evolutionarily conserved basic helix-loop-helix transcription (bHLH) factor that is required for differentiation of skeletal muscle, and its homozygous deletion in mice results in perinatal death from respiratory failure due to the lack of muscle fibers. Since the histology of skeletal muscle in myogenin null mice is reminiscent of that found in severe congenital myopathy patients, many of whom also die of respiratory complications, we sought to test the hypothesis that an aberrant human myogenin (myf4) coding region could be associated with some congenital myopathy conditions. With PCR amplification, we found similarly sized PCR products for the three exons of the myogenin gene in DNA from 37 patient and 40 control individuals. In contrast to previously reported sequencing of human myogenin (myf4), we describe with automated sequencing several base differences in flanking and coding regions plus an additional 659 and 498 bp in the first and second introns, respectively, in all 37 patient and 40 control samples. We also find a variable length (CA)-dinucleotide repeat in the second intron, which may have utility as a marker for future linkage studies. In summary, no causative mutations were detected in the myogenin coding locus of genomic DNA from 37 patients with severe congenital myopathy., (Copyright 1999 Academic Press.)

Almost 20% of Californian smokers do not smoke daily. Although occasional (non-daily) smoking occurs during uptake, a stable pattern of occasional smoking may imply a milder level of nicotine addiction. We use a longitudinal population sample of smokers interviewed in both 1990 and 1992 to evaluate the stability of occasional smoking. Further, we use 1992 data, including smokers only interviewed in 1992, to compare occasional smokers who have (ever-daily) and have not (never-daily) smoked daily for at least 6 months, and contrast them to daily smokers for key variables associated with addiction. All our analyses exclude uptake smokers. Two-thirds of never-daily occasional smokers in 1992 also smoked occasionally in 1990, compared to only about 40% of ever-daily occasional smokers. Never-daily occasional smokers smoke less than ever-daily ones. They are more often under age 40 years, of Hispanic origin, and were more likely to begin regular smoking beyond their teen years. Demographically, ever-daily occasional smokers were similar to daily smokers except for being more educated. However, both ever-daily and never-daily smokers differed from daily smokers with respect to long-term quitting history, plans to quit, confidence they could quit, and belief they are addicted to cigarettes. Our findings suggest that occasional smoking can be a stable pattern for long periods. Occasional smokers, particularly never-daily ones, appear to be much less addicted to nicotine than daily smokers.

Low-cost generic cigarettes grew dramatically in market share between 1990 and 1993, raising concerns that some smokers might view generics as an alternative to quitting. We report sociodemographic predictors of generic brand choice among a cross-sectional sample of California smokers and investigate changes in brand choice in a longitudinal sample of California smokers between 1990 and 1992. We also focus on brand preferences among California adolescents. One third of smokers who switched cigarette brands between 1990 and 1992 switched to generics. Non-Hispanic whites, rural residents, and lower income smokers were twice as likely to buy generics as other smokers were. Heavy cigarette consumption was strongly associated with smoking generic cigarettes. Women appeared more price-sensitive in cigarette purchasing than men did, and generic brands were the most frequently purchased cigarettes for female smokers older than age 45. Generics were less popular among adolescents than among adults. Generic cigarettes provide a low-cost alternative to price-sensitive smokers, but further studies are needed to establish the role and influence of generic cigarettes on smoking prevalence and public health. Medical Subject Headings (MeSH): smoking, smoking cessation, adolescent behavior, women, prevalence.

Objective: Compare 5-year melanoma survival rates to rates in medical literature., Design: Retrospective., Setting: Hospital in Tijuana, Mexico., Patients: White adult patients (N = 153) with superficial spreading and nodular melanoma, aged 25-72 years., Intervention: Gerson's diet therapy: lactovegetarian; low sodium, fat and (temporarily) protein; high potassium, fluid, and nutrients (hourly raw vegetable/fruit juices). Metabolism increased by thyroid; calorie supply limited to 2600-3200 calories per day. Coffee enemas as needed for pain and appetite., Main Outcome Measure: 5-year survival rates by stage at admission., Results: Of 14 patients with stages I and II (localized) melanoma, 100% survived for 5 years, compared with 79% of 15,798 reported by Balch. Of 17 with stage IIIA (regionally metastasized) melanoma, 82% were alive at 5 years, in contrast to 39% of 103 from Fachklinik Hornheide. Of 33 with combined stages IIIA + IIIB (regionally metastasized) melanoma, 70% lived 5 years, compared with 41% of 134 from Fachklinik Hornheide. We propose a new stage division: IVA (distant lymph, skin, and subcutaneous tissue metastases), and IVB (visceral metastases). Of 18 with stage IVA melanoma, 39% were alive at 5 years, compared with only 6% of 194 from the Eastern Cooperative Oncology Group. Survival impact was not assessed for stage IVB. Male and female survival rates were identical for stages I-IIIB, but stage IVA women had a strong survival advantage., Conclusions: The 5-year survival rates reported here are considerably higher than those reported elsewhere. Stage IIIA/B males had exceptionally high survival rates compared with those reported by other centers.

Increasing numbers of patients more than 70 years old are at risk from coronary artery disease. The continued success of coronary artery bypass operation in selected patients provides impetus for applying this procedure to older patients as well. Our results indicate coronary artery operation is effective in older patients and has a low mortality (3% in our series). In patients in this age group, coronary artery operation can be combined with other procedures, when indicated, such as cardiac valve replacement or repair, left ventricular aneurysmectomy, carotid endarterectomy, and cholecystectomy.