Fluorochrome Selection for Imaging Intraoperative Ovarian Cancer Probes

The identification and removal of all gross and microscopic tumor to render the patient disease free represents a huge challenge in ovarian cancer treatment. The presence of residual disease is an independent negative prognostic factor. Herein, we describe the synthesis and the “in vitro” evaluation of compounds as cyclooxygenase (COX)-1 inhibitors, the COX-1 isoform being an ovarian cancer biomarker, each bearing fluorochromes with different fluorescence features. Two of these compounds N-[4-(9-dimethylimino-9H-benzo[a]phenoxazin-5-ylamino) butyl]-2-(3,4-bis(4-methoxyphenyl)isoxazol-5-yl)acetamide chloride (RR11) and 3-(6-(4-(2-(3,4-bis(4-methoxyphenyl)isoxazole-5-yl)acetamido)butyl)amino-6-oxohexyl)-2-[7-(1,3-dihydro-1,1-dimethyl-3-ethyl 2H-benz[e]indolin-2-yl-idene)-1,3,5-heptatrienyl]-1,1-dimethyl-3-(6-carboxilato-hexyl)-1H-benz[e]indolium chloride, 23 (MSA14) were found to be potent and selective inhibitors of cyclooxygenase (COX)-1 “in vitro”, and thus were further investigated “in vivo”. The IC50 values were 0.032 and 0.087 µM for RR11 and 23 (MSA 14), respectively, whereas the COX-2 IC50 for RR11 is 2.4 µM while 23 (MSA14) did not inhibit COX-2 even at a 50 µM concentration. Together, this represented selectivity index = 75 and 874, respectively. Structure-based virtual screening (SBVS) performed with the Fingerprints for Ligands and Proteins (FLAP) software allowed both to differentiate highly active compounds from less active and inactive structures and to define their interactions inside the substrate-binding cavity of hCOX1. Fluorescent probes RR11 and 23 (MSA14), were used for preliminary near-infrared (NIR) fluorescent imaging (FLI) in human ovarian cancer (OVCAR-3 and SKOV-3) xenograft models. Surprisingly, a tumor-specific signal was observed for both tested fluorescent probes, even though this signal is not linked to the presence of COX-1.publishedVersio

Infected pancreatic necrosis: outcomes and clinical predictors of mortality. A post hoc analysis of the MANCTRA-1 international study

: The identification of high-risk patients in the early stages of infected pancreatic necrosis (IPN) is critical, because it could help the clinicians to adopt more effective management strategies. We conducted a post hoc analysis of the MANCTRA-1 international study to assess the association between clinical risk factors and mortality among adult patients with IPN. Univariable and multivariable logistic regression models were used to identify prognostic factors of mortality. We identified 247 consecutive patients with IPN hospitalised between January 2019 and December 2020. History of uncontrolled arterial hypertension (p = 0.032; 95% CI 1.135-15.882; aOR 4.245), qSOFA (p = 0.005; 95% CI 1.359-5.879; aOR 2.828), renal failure (p = 0.022; 95% CI 1.138-5.442; aOR 2.489), and haemodynamic failure (p = 0.018; 95% CI 1.184-5.978; aOR 2.661), were identified as independent predictors of mortality in IPN patients. Cholangitis (p = 0.003; 95% CI 1.598-9.930; aOR 3.983), abdominal compartment syndrome (p = 0.032; 95% CI 1.090-6.967; aOR 2.735), and gastrointestinal/intra-abdominal bleeding (p = 0.009; 95% CI 1.286-5.712; aOR 2.710) were independently associated with the risk of mortality. Upfront open surgical necrosectomy was strongly associated with the risk of mortality (p < 0.001; 95% CI 1.912-7.442; aOR 3.772), whereas endoscopic drainage of pancreatic necrosis (p = 0.018; 95% CI 0.138-0.834; aOR 0.339) and enteral nutrition (p = 0.003; 95% CI 0.143-0.716; aOR 0.320) were found as protective factors. Organ failure, acute cholangitis, and upfront open surgical necrosectomy were the most significant predictors of mortality. Our study confirmed that, even in a subgroup of particularly ill patients such as those with IPN, upfront open surgery should be avoided as much as possible. Study protocol registered in ClinicalTrials.Gov (I.D. Number NCT04747990)

Photobehavior of an Acidochromic Dinitrophenyl-Hydrazinylidene Derivative: A Case of Total Internal Conversion

Research in photochemistry is always looking for novel compounds that can serve a role in applications ranging from medicine to environmental science. Push–pull compounds with protonable groups represent an interesting class of molecules in this sense, as they can prove to be sensitive to changes in both the acidity and polarity of the medium, becoming valuable as sensors and probes. Hence, in this work, a new dinitrophenyl-hydrazinylidene derivative with multiple protonable centers has been specifically designed and synthesized. The molecule showed an important acidochromism in the visible, with three differently-protonated species under acidic, neutral, and basic conditions, each characterized by a peculiar absorption spectrum. The photophysical characterization of this compound revealed an ultrafast excited-state deactivation, as described by femtosecond transient absorption experiments, and the hints of charge-transfer dynamics, as supported by the observed solvatochromism and quantum-mechanical calculations. These properties led to almost undetectable fluorescence that, together with negligible intersystem crossing and the absence of reactive pathways, points to the preference for a total non-radiative deactivation mechanism, i.e., internal conversion. This intriguing behavior stimulates interest in light of possible applications of the investigated acidochromic dye as a probe in photoacoustic imaging, which offers an alternative to classical fluorescence imaging

Synthetic Routes to TEG-Substituted Diketopyrrolopyrrole-Based Low Band-Gap Polymers

We report herein general synthetic routes to novel TEG-functionalized DPP-based co-polymers (TEG = triethylene glycol; DPP = diketopyrrolopyrrole) that display alternating TEG-substituted DPP moieties with various functionalized donor units; donor units contain moieties such as polythiophene segments decorated with thermocleavable tertiary esters or additional TEG chains and alkoxy-substituted benzodithiophenes. The synthetic approaches are based on Stille coupling chemistry or, for the first time for TEG-substituted DPP-based polymers, on direct heteroarylation polymerizations. Spectroscopic and electrochemical characterization as well as preliminary tests in photovoltaic cells are also reported

Metal-free synthesis of bisthiophene-core donor acceptor organic photosensitizers for dye-sensitized solar cells

Abstract Three novel donor-π-acceptor molecules with a bis-thiophene core have been synthesized through a simple and versatile metal-free synthetic procedure. Study of their optical and electrochemical properties, and a preliminary evaluation of their use as dyes in dye sensitized solar cells (DSSC) are presented. The proposed synthetic protocol results in a drastic reduction of the size and complexity of the sensitizer molecule, possibly enabling cost decrease by overall yield improvement and easy scalability. Particular attention has been paid to limit the environmental impact by reducing the number of synthetic steps and especially avoiding the use of organometallic reactions

Amphiphilicity-Controlled Localization of Red Emitting Bicationic Fluorophores in Tumor Cells Acting as Bio-Probes and Anticancer Drugs

Small organic molecules arouse lively interest for their plethora of possible biological applications, such as anticancer therapy, for their ability to interact with nucleic acids, or bioimaging, thanks to their fluorescence emission. Here, a panchromatic series of styryl-azinium bicationic dyes, which have already proved to exhibit high water-solubility and significant red fluorescence in water, were investigated through spectrofluorimetric titrations to assess the extent of their association constants with DNA and RNA. Femtosecond-resolved transient absorption spectroscopy was also employed to characterize the changes in the photophysical properties of these fluorophores upon interaction with their biological targets. Finally, in vitro experiments conducted on tumor cell lines revealed that some of the bicationic fluorophores had a peculiar localization within cell nuclei exerting important antiproliferative effects, others were instead found to localize in the cytoplasm without leading to cell death, being useful to mark specific organelles in light of live cell bioimaging. Interestingly, this molecule-dependent behavior matched the different amphiphilicity featured by these bioactive compounds, which are thus expected to be caught in a tug-of-war between lipophilicity, ensured by the presence of aromatic rings and needed to pass cell membranes, and hydrophilicity, granted by charged groups and necessary for stability in aqueous media

Harmaline-based scaffold as Human Caseinolytic Protease P (hClpP) inducers for Diffuse Intrinsic Pontine Glioma (DIPG) treatment

Diffuse intrinsic pontine glioma (DIPG) is a highly aggressive pediatric brainstem tumor which accounts for about 10% to 20% of all childhood brain tumors1, with a peak of incidence between 6 and 8 years. Prognosis is extremely poor, due to localization and inoperability. Indeed, surgery cannot be performed, and focal radiotherapy remains the standard of care currently that has demonstrated clinical efficacy. Over the last decade, preclinical studies identified ONC201, an experimental anticancer drug from the imipridone class to be endowed with cytotoxic activity against multiple human cancer cell lines, including DIPG. Only recently, the X-ray analysis of the complex of the human mitochondrial caseinolytic serine protease type C (hClpP) and ONC201 (PDB ID: 6DL7, Figure 1)2, has allowed to identify hClpP as its main direct target. This provided the rationale to evaluate the hClpP activity in patients recruited in ongoing clinical trials using ONC201 as a drug. Downstream of target engagement, hClpP plays a pivotal role in the quality control of mitochondrial proteins involved in important cellular pathways. The hyperactivation of hClpP, due to the interaction with ONC201, alters the structure and mitochondrial function, causes the death of cancer cells, without affecting healthy cells. To date, a computational pipeline was applied to perform a FLAP virtual screening of 1500 commercial natural products (CNPs) followed by Volsurf analysis to identify a novel original scaffold as hClpP inducers able to cross blood-barrier brain. In silico investigation identifies Harmaline, a fluorescent indole alkaloid, with anti-inflammatory and anti-cancer properties. Harmaline chemical structure has been pportunely modified to find out structural determinants for the hClpP induction. The Structure Activity Relationship Study results will be presented and discussed

Different In Silico Approaches Using Heterocyclic Derivatives against the Binding between Different Lineages of SARS-CoV-2 and ACE2

Over the last few years, the study of the SARS-CoV-2 spike protein and its mutations has become essential in understanding how it interacts with human host receptors. Since the crystallized structure of the spike protein bound to the angiotensin-converting enzyme 2 (ACE2) receptor was released (PDB code 6M0J), in silico studies have been performed to understand the interactions between these two proteins. Specifically, in this study, heterocyclic compounds with different chemical characteristics were examined to highlight the possibility of interaction with the spike protein and the disruption of the interaction between ACE2 and the spike protein. Our results showed that these compounds interacted with the spike protein and interposed in the interaction zone with ACE2. Although further studies are needed, this work points to these heterocyclic push–pull compounds as possible agents capable of interacting with the spike protein, with the potential for the inhibition of spike protein–ACE2 binding

Cyclooxygenase-1 Inhibition: A Promising Theragnostic Approach for Ovarian Cancer

Ovarian Cancer (OC) is nowadays the 3rd most common gynaecologic cancer worldwide, with a 5-years survival rate lower than 50%. The most frequent OC histological subtype is high grade serous ovarian cancer (HGSOC), responsible for the highest mortality rate of all gynaecologic malignancies since most patients are diagnosed at late stages. Moreover, despite an initial response to chemotherapy agents, tumour relapse frequently occurs within 3 years from surgery, with the development of drug resistance. Hence, the identification of prognostic biomarkers to assess drug response is an evident ad also urgent clinical need. Over the last two decades, the progress in imaging technology led to a great revolution in the biomedical field, which is now benefiting from fluorescence imaging. Specifically, breakthroughs in fluorophore chemistry and the identification of targetable biomarkers represent valuable pharmacological tool for oncologists. The identification and removal of all macroscopic and microscopic tumours to render the patient disease-free represents a huge challenge in OC treatment. Cyclooxygenase (COX)-1 and COX-2 catalyze the rate-limiting step in the conversion of arachidonic acid to PGs [1] and are involved in tumour progression by inducing proliferation, invasion, and metastasis formation [2]. HGSOC expresses high levels of COX-1 rather than COX-2. Therefore, COX-1 has been recently proposed as an ideal biomarker for the OC.Hence, new compounds as cancer imaging agents and COX-1 inhibitors, each bearing fluorochromes with different fluorescence features, were projected, synthesized, and in vitro and in vivo pharmacologically evaluated. Two of these compounds N-[4-(9-dimethylimino-9Hbenzo[a]phenoxazin-5-ylamino) butyl]-2-(3,4-bis(4-methoxyphenyl)isoxazol-5-yl)acetamide chloride (RR11) and 3-(6-(4-(2-(3,4-bis(4-methoxyphenyl)isoxazole-5-yl)acetamido)butyl)amino-6-oxohexyl)-2- [7-(1,3-dihydro1,1-dimethyl-3-ethyl 2H-benz[e]indolin-2-yl-idene)-1,3,5-heptatrienyl]-1,1-dimethyl-3-(6-carboxilato-hexyl)- 1H-benz[e]indolium chloride (MSA14) were found to be potent COX-1 inhibitors. The COX-1 IC50 values were 0.032 and 0.087 μM for RR11 and MSA 14, respectively, whereas the COX-2 IC50 for RR11 is 2.4 μM while MSA 14 did not inhibit COX-2 even at a 50 μM. Structure-based virtual screening (SBVS) performed with the Fingerprints for Ligands and Proteins (FLAP) software allowed both to differentiate highly active compounds from less active and inactive structures and to define their interactions inside the substrate-binding cavity of hCOX1 [1, 2]. Fluorescent probes RR11 and MSA14 were used for preliminary near-infrared (NIR) fluorescent imaging (FLI) in OVCAR-3 and SKOV-3 xenograft models and the results of this study will be presented