Design and Evaluation of ZD06519, a Novel Camptothecin Payload for Antibody Drug Conjugates

In recent years, the field of antibody drug conjugates (ADC) has seen a resurgence, largely driven by the clinical benefit observed in patients treated with ADCs incorporating camptothecin-based topoisomerase I inhibitor payloads. Herein, we present the development of a novel camptothecin ZD06519 (FD1), which has been specifically designed for its application as an ADC payload. A panel of camptothecin analogs with different substituents at the C-7 and C-10 positions of the camptothecin core was prepared and tested in vitro. Selected compounds spanning a range of potency and hydrophilicity were elaborated into drug-linkers, conjugated to trastuzumab, and evaluated in vitro and in vivo. ZD06519 was selected on the basis of its favorable properties as a free molecule and as an antibody conjugate, which include moderate free payload potency (∼1 nmol/L), low hydrophobicity, strong bystander activity, robust plasma stability, and high-monomeric ADC content. When conjugated to different antibodies using a clinically validated MC-GGFG-based linker, ZD06519 demonstrated impressive efficacy in multiple cell line-derived xenograft models and noteworthy tolerability in healthy mice, rats, and non-human primates.

Abstract 2641: ZW191, a novel FRa-targeting antibody drug conjugate bearing a topoisomerase 1 inhibitor payload

Background: Folate Receptor alpha (FRa) is a validated cell surface cancer target that is prevalently expressed in multiple cancers with high unmet need, including ovarian cancer and other gynecological cancers, while exhibiting minimal expression in normal tissues. Due to FRa’s favorable expression profile, multiple antibody-drug conjugates (ADCs) are being explored in this setting. Here we present the preclinical characterization of a new anti-FRa ADC, ZW191. ZW191 is an antibody drug conjugate (ADC) comprised of a humanized IgG1 antibody conjugated to a novel camptothecin-based topoisomerase 1 inhibitor payload, ZD06519, via a maleimidocaproyl (MC) anchor and a glycyl glycyl phenylalanyl glycine (GGFG)-aminomethyl (AM) cleavable linker at a drug-to-antibody ratio (DAR) of 8.

Materials and Methods: The novel antibody and drug-linker components of ZW191 were generated, characterized, and optimally integrated. The apparent binding affinity and cellular internalization of the ZW191 antibody, and the intracellular concentration of the released camptothecin payload, ZD06519, were determined in FRa-expressing cells. Additionally, the binding specificity of the ZW191 antibody was determined using a cell microarray technology to test for binding against over 6,000 full length proteins that are individually over-expressed in human cells. Tumor spheroid cancer cell cultures were utilized to determine the cytotoxicity of ZW191 and the ability of ZW191 to penetrate the layers of the three-dimensional (3D) spheroid. The bystander activity of ZW191 was assessed using antigen positive and negative co-culture experiments. The anti-tumor activity of ZW191 was evaluated in a panel of cell line-derived xenograft (CDX) and patient-derived xenograft (PDX) ovarian cancer models spanning a range of FRa expression. ZW191 was evaluated in toxicology and pharmacokinetic (PK) studies performed in rodents and non-human primates (NHP).

Results: The antibody component of ZW191 features a favorable binding profile with strong and exclusive binding to FRa, and drives superior tumor spheroid penetration, cellular internalization, and payload delivery compared to FRa targeted antibodies used in other ADCs. ZW191 demonstrates potent activity in FRa expressing 3D tumor spheroid cultures and effective bystander activity. In a panel of CDX and PDX models representing a range of FRa expression, ZW191 demonstrates compelling anti-tumor activity at exposures that are estimated to be readily achievable in the clinic. ZW191 was tolerated up to 200 mg/kg in a two-dose rat study and at 30 mg/kg in a two-dose NHP study, with favorable PK. The promising efficacy, tolerability, and PK supports the potential of ZW191 as a novel therapeutic agent that may help address unmet need in patients with high and low FRa-expressing cancers.

Citation Format: Sam Lawn, Andrea Hernandez Rojas, Raffaele Colombo, Dayananda Siddappa, Jodi Wong, Kaylee Wu, Vincent Fung, Dunja Urosev, Luying Yang, Jamie R. Rich, Stuart D. Barnscher. ZW191, a novel FRa-targeting antibody drug conjugate bearing a topoisomerase 1 inhibitor payload [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2641.

Engineered Ultrasmall Nanoparticle Drug-Immune Conjugates with "Hit and Run" Tumor Delivery to Eradicate Gastric Cancer

Despite advances by recently approved antibody-drug conjugates in treating advanced gastric cancer patients, substantial limitations remain. Here, several key obstacles are overcome by developing a first-in-class ultrasmall (sub-8-nanometer (nm)) anti-human epidermal growth factor receptor 2 (HER2)-targeting drug-immune conjugate nanoparticle therapy. This multivalent fluorescent core-shell silica nanoparticle bears multiple anti-HER2 single-chain variable fragments (scFv), topoisomerase inhibitors, and deferoxamine moieties. Most surprisingly, drawing upon its favorable physicochemical, pharmacokinetic, clearance, and target-specific dual-modality imaging properties in a "hit and run" approach, this conjugate eradicated HER2-expressing gastric tumors without any evidence of tumor regrowth, while exhibiting a wide therapeutic index. Therapeutic response mechanisms are accompanied by the activation of functional markers, as well as pathway-specific inhibition. Results highlight the potential clinical utility of this molecularly engineered particle drug-immune conjugate and underscore the versatility of the base platform as a carrier for conjugating an array of other immune products and payloads.

The therapeutic window of antibody drug conjugates: A dogma in need of revision

Despite a prevailing dogma wherein antibody drug conjugates (ADCs) increase the maximum tolerated dose of potent cytotoxin payloads while lowering the minimum effective dose, mounting clinical evidence argues that the tolerated doses of ADCs are not significantly different from those of related small molecules. Nonetheless, when dosed at or near the maximum tolerated dose, certain ADCs demonstrate improved efficacy. Understanding the challenges and opportunities for this class of biotherapeutics will help improve the design of next-generation ADCs.

Exercise training decreases oxidative stress in skeletal muscle of rats with pulmonary arterial hypertension

The effects of exercise training on oxidative stress in gastrocnemius of rats with pulmonary hypertension were studied. Four groups were established: sedentary control (SC), sedentary monocrotaline (SM), trained control (TC), trained monocrotaline (TM). Exercise was applied for 4 weeks, 5 days/week, 50-60 min/session, at 60% of VO₂ max. Right ventricular (RV) pressures were measured, heart and gastrocnemius were removed for morphometric/biochemical analysis. Lipid peroxidation (LPO), H₂O₂, GSH/GSSG, and activity/expression of antioxidant enzymes were evaluated. Increased RV hypertrophy, systolic and end-diastolic pressures (RVEDP) were observed in SM animals, and the RVEDP was decreased in TM vs. SM. H₂O₂, SOD-1, and LPO were higher in the SM group than in SC. In TM, H₂O₂ was further increased when compared to SM, with a rise in antioxidant defences and a decrease in LPO. GSH/GSSG was higher only in the TC group. Exercise induced an efficient antioxidant adaptation, preventing oxidative damage to lipids.

Cyclopentadiene as a Multifunctional Reagent for Normal- and Inverse-Electron Demand Diels-Alder Bioconjugation

Optimizing the Diels-Alder (DA) reaction for aqueous coupling has resulted in practical methods to link molecules such as drugs and diagnostic agents to proteins. Both normal electron demand (NED) and inverse electron demand (IED) DA coupling schemes have been employed, but neither mechanism entails a common multipurpose reactive group. This report focuses on expanding the bioconjugation toolbox for cyclopentadiene through the identification of reactive groups that couple through NED or IED mechanisms in aqueous solution. Dienophiles and tetrazine derivatives were screened for reactivity and selectivity toward antibodies bearing cyclopentadiene amino acids to yield bioconjugates. Twelve NED dienophiles and four tetrazine-based IED substrates were identified as capable of practical biocoupling. Furthermore, tetrazine ligation to cyclopentadiene occurred at a rate of 3.3 ± 0.5 M^-1 s^-1 and was capable of bioorthogonal transformations, as evidenced by the selective protein labeling in serum. Finally, an antibody-drug conjugate (ADC)-bearing monomethyl auristatin E was prepared via tetrazine conjugation to cyclopentadiene. The resulting ADC was stable and demonstrated potent activity in vitro. These findings expand the utility of cyclopentadiene as a tool to couple entities to proteins via dual DA addition mechanisms.

Monitoring the haemodynamic response to visual stimulation in glaucoma patients

In this paper, we used time-domain functional near infrared spectroscopy (TD-fNIRS) to evaluate the haemodynamic response function (HRF) in the occipital cortex following visual stimulation in glaucomatous eyes as compared to healthy eyes. A total of 98 subjects were enrolled in the study and clinically classified as healthy subjects, glaucoma patients (primary open-angle glaucoma) and mixed subjects (i.e. with a different classification for the two eyes). After quality check data were used from HRF of 73 healthy and 62 glaucomatous eyes. The amplitudes of the oxygenated and deoxygenated haemoglobin concentrations, together with their latencies with respect to the stimulus onset, were estimated by fitting their time course with a canonical HRF. Statistical analysis showed that the amplitudes of both haemodynamic parameters show a significant association with the pathology and a significant discriminating ability, while no significant result was found for latencies. Overall, our findings together with the ease of use and noninvasiveness of TD-NIRS, make this technique a promising candidate as a supporting tool for a better evaluation of the glaucoma pathology.

Reference Protocol to Assess Analytical Performance of Higher Order Structural Analysis Measurements: Results from an Interlaboratory Comparison

Measurements of protein higher order structure (HOS) provide important information on stability, potency, efficacy, immunogenicity, and biosimilarity of biopharmaceuticals, with a significant number of techniques and methods available to perform these measurements. The comparison of the analytical performance of HOS methods and the standardization of the results is, however, not a trivial task, due to the lack of reference protocols and reference measurement procedures. Here, we developed a protocol to structurally alter and compare samples of somatropin, a recombinant biotherapeutic, and describe the results obtained by using a number of techniques, methods and in different laboratories. This, with the final aim to provide tools and generate a pool of data to compare and benchmark analytical platforms and define method sensitivity to structural changes. Changes in somatropin HOS, induced by the presence of zinc at increasing concentrations, were observed, both globally and at more localized resolution, across many of the methods utilized in this study and with different sensitivities, suggesting the suitability of the protocol to improve understanding of inter- and cross-platform measurement comparability and assess analytical performance as appropriate.

Risk factors for residual disease at re-TUR in a large cohort of T1G3 patients

INTRODUCTION AND OBJECTIVES

The goals of transurethral resection of a bladder tumor (TUR) are to completely resect the lesions and to make a correct diagnosis in order to adequately stage the patient. It is well known that the presence of detrusor muscle in the specimen is a prerequisite to minimize the risk of under staging. Persistent disease after resection of bladder tumors is not uncommon and is the reason why the European Guidelines recommended a re-TUR for all T1 tumors. It was recently published that when there is muscle in the specimen, re-TUR does not influence progression or cancer specific survival. We present here the patient and tumor factors that may influence the presence of residual disease at re-TUR.

MATERIAL AND METHODS

In our retrospective cohort of 2451 primary T1G3 patients initially treated with BCG, pathology results for 934 patients (38.1%) who underwent re-TUR are available. 74% had multifocal tumors, 20% of tumors were more than 3 cm in diameter and 26% had concomitant CIS. In this subgroup of patients who underwent re-TUR, there was no residual disease in 267 patients (29%) and residual disease in 667 patients (71%): Ta in 378 (40%) and T1 in 289 (31%) patients. Age, gender, tumor status (primary/recurrent), previous intravesical therapy, tumor size, tumor multi-focality, presence of concomitant CIS, and muscle in the specimen were analyzed in order to evaluate risk factors of residual disease at re-TUR, both in univariate analyses and multivariate logistic regressions.

RESULTS

The following were not risk factors for residual disease: age, gender, tumor status and previous intravesical chemotherapy. The following were univariate risk factors for presence of residual disease: no muscle in TUR, multiple tumors, tumors > 3 cm, and presence of concomitant CIS. Due to the correlation between tumor multi-focality and tumor size, the multivariate model retained either the number of tumors or the tumor diameter (but not both), p < 0.001. The presence of muscle in the specimen was no longer significant, while the presence of CIS only remained significant in the model with tumor size, p < 0.001.

CONCLUSIONS

The most significant factors for a higher risk of residual disease at re-TUR in T1G3 patients are multifocal tumors and tumors more than 3 cm. Patients with concomitant CIS and those without muscle in the specimen also have a higher risk of residual disease.

Hypoalbuminemia in COVID-19: assessing the hypothesis for underlying pulmonary capillary leakage

BACKGROUND

Since the first observations of patients with COVID-19, significant hypoalbuminaemia was detected. Its causes have not been investigated yet.

OBJECTIVE

We hypothesized that pulmonary capillary leakage affects the severity of respiratory failure, causing a shift of fluids and proteins through the epithelial-endothelial barrier.

METHODS

One hundred seventy-four COVID-19 patients with respiratory symptoms, 92 admitted to the intermediate medicine ward (IMW) and 82 to the intensive care unit (ICU) at Luigi Sacco Hospital in Milan, were studied.

RESULTS

Baseline characteristics at admission were considered. Proteins, interleukin 8 (IL-8) and interleukin 10 (IL-10) in bronchoalveolar lavage fluid (BALF) were analysed in 26 ICU patients. In addition, ten autopsy ultrastructural lung studies were performed in patients with COVID-19 and compared with postmortem findings in a control group (bacterial pneumonia-ARDS and H1N1-ARDS). ICU patients had lower serum albumin than IMW patients [20 (18-23) vs 28 (24-33) g L^-1 , P < 0.001]. Serum albumin was lower in more compromised groups (lower PaO₂ -to-FiO₂ ratio and worst chest X-ray findings) and was associated with 30 days of probability of survival. Protein concentration was correlated with IL-8 and IL-10 levels in BALF. Electron microscopy examinations of eight out of ten COVID-19 lung tissues showed loosening of junctional complexes, quantitatively more pronounced than in controls, and direct viral infection of type 2 pneumocytes and endothelial cells.

CONCLUSION

Hypoalbuminaemia may serve as severity marker of epithelial-endothelial damage in patients with COVID-19. There are clues that pulmonary capillary leak syndrome plays a key role in the pathogenesis of COVID-19 and might be a potential therapeutic target.

Sexual Risk Behaviors Associated with Sexually Transmitted Infections in a US Military Population Living with HIV After the Repeal of "Don't Ask, Don't Tell"

Risk behaviors associated with sexually transmitted infections (STIs) among people living with HIV (PLWH) have not been well characterized in the US military. We identified risk behaviors associated with a new STI in this population after the repeal of "Don't Ask, Don't Tell." US Military HIV Natural History Study participants who completed the risk behavior questionnaire (RBQ) between 2014 and 2017 and had at least 1 year of follow-up were included (n = 1589). Logistic regression identified behaviors associated with incident STI in the year following RBQ completion. Overall, 18.9% acquired an STI and 52.7% reported condom use at last sexual encounter. Compared with those with no new sex partners, participants with between one and four or five or more new partners were 1.71 [1.25-2.35] and 6.12 [3.47-10.79] times more likely to get an STI, respectively. Individuals reporting low or medium/high perceived risk of STI were 1.83 [1.23-2.72] and 2.65 [1.70-4.15] times more likely to acquire a new STI than those reporting no perceived risk, respectively. Participants who preferred not to answer about sexual preference, number of new partners, or perceived STI risk were also more likely to acquire a new STI. Our study illustrates that despite regular access to health care and accurate perceptions of risk, rates of STI among PLWH remain high in the US military setting, as in others. Given the potential individual and public health consequences of STI coinfection after HIV, more work is needed to assess interventions aimed at sexual behavior change for PLWH.

Conduction defect rates in high risk surgical patients undergoing TAVR with or without PCI during a single hospitalization: a nationwide study

Introduction

Since the first documented transaortic valve replacement (TAVR) by Cribier et. al. in 2002 as a less invasive treatment approach for severe aortic stenosis (AS) and following the landmark PARTNER 1 trial, the Food and Drug Administration (FDA) approved TAVR in 2012 for patients deemed to be at high surgical risk. In recent years, there has been an expansion of indications to include low surgical risk candidates. Risk factors associated with aortic stenosis overlap with those for coronary artery disease, and up to 40–70% of patients referred for replacement have incidental obstructive coronary lesions. The best timing of intervention for concurrent pathology has been a subject of debate; recommendations support combined TAVR and percutaneous coronary intervention (PCI) for treatment of ostial/proximal lesions or in unstable patients. TAVR is not free of complications and a concern has been on post-deployment alterations of the heart's electrical system that may result in need for permanent pacemaker (PPM) implantation.

Purpose

To secure the aortic valve in place during a TAVR, there is a known risk of inducing a conduction disturbance. This study examined conduction abnormalities in patients undergoing a concurrent TAVR and PCI during the same hospitalization.

Methods

The patient population was obtained from the Nation Inpatient Sample database, which is a stratified systematic random sample of 20% hospital admissions in the USA. ICD-9 Revision-Clinical Modification procedure codes were used to identify all patients undergoing PCI and TAVR during the same admission between 2011 and 2014. Patients 50 years and older were included. Those with a history of a PPM were excluded. Outcomes of interest included new PPM, left bundle branch block (LBBB), first degree/second degree/complete AV bock, all-cause in-hospital mortality, and length of stay. Multivariate logistic regression analysis was used while adjusting for patient and procedural confounders.

Results

Between 2011 and 2014, 29,998 patients underwent TAVR, of which 1070 had a concurrent PCI during the same hospital admission. There was no noted increase in odds of PPM (OR 0.42 95% CI: 0.010–1.72), LBBB (OR 1.89 95% CI 0.65–5.49), second degree AV block (OR 1.49 95% CI: 0.21–10.50), complete AV block (OR: 1.44, 95% CI: 0.57–3.63), atrial fibrillation (OR 0.95 95% CI: 0.46–1.94), or atrial flutter (OR 1.75 95% 0.38–7.94) in those undergoing PCI+TAVR compared to TAVR alone. The odds of all cause, in-hospital mortality was 4.44 (95% CI: 1.25–15.8) times greater in those with a PCI+TAVR during the same admission compared to TAVR alone. Length of stay was 7.5 days (95% CI: 7.25–7.75) in those undergoing a TAVR compared to 12.4 days (95% CI: 10.67–14.15) in those with a TAVR+PCI, p&lt;0.0001.

Conclusion

Periprocedural PCI and TAVR during the same hospitalization does not further increase risk of major conduction defects or rates of pacemaker implantation.

Funding Acknowledgement

Type of funding source: None

Cardiovascular outcomes of concurrent TAVR and PCI compared to TAVR alone using the U.S. national inpatient sample: 2011–2014

Introduction

The high concurrent prevalence of coronary artery disease (CAD) in patients with severe aortic stenosis (AS) inevitably forces experts to face a pressing decision whether to revascularize and replace the aortic valve at the same time. While current recommendations support combined transaortic valve replacement (TAVR) and percutaneous coronary intervention (PCI) for treatment of ostial/proximal lesions, or in unstable patients, less clear indications exist for patients not fulfilling this pattern. The population undergoing concomitant TAVR and PCI can be clinically challenging and thus it is important to further characterize prognosis and major cardiovascular outcomes in this cohort.

Purpose

To assess the likelihood of major cardiovascular events in patients undergoing TAVR with PCI during the same hospital admission compared to those with TAVR only. As well as to have a better understanding of the risks and possible benefits of a combined procedure and thus aid in clinical decision-making.

Methods

This study used the National Inpatient Sample (NIS) of patients undergoing a TAVR from 2011 to 2014. The NIS is a stratified systematic random sample of 20% hospital admissions in the United States. Internal Classification of Diseases Ninth Revision-Clinical Modification procedure codes were used to identify all patients that underwent a PCI and/or TAVR during the same admission. Patients aged greater than 50 years were included. Outcomes of interest included all-cause in-hospital mortality, new TIA/ischemic stroke, cardiogenic shock, cardiac arrest, hemopericardium, and length of stay. Multivariate logistic regression was used to adjust for patient and procedural confounders.

Results

Among the 33,652 patients who underwent TAVR between 2011 and 2014, 1,179 underwent a PCI during the same hospital admission. The adjusted odds of all-cause in-hospital mortality was 3.05 (95% CI 1.95–4.75) in those with a TAVR+PCI compared to TAVR only. The adjusted odds of cardiac arrest and cardiogenic shock was 2.50 (95% CI: 1.48–4.22) and 4.85 (95% CI 3.05–7.7), respectively. Furthermore, the odds of a new TIA/ischemic stroke during the same admission was 0.86 (95% CI 0.35–2.07) and odds of hemopericardium was 3.13 (95% CI: 0.71–13.70).

Conclusion

Concomitant PCI and TAVR during the same hospitalization was associated with higher all-cause in-hospital mortality, increased length of stay, cardiogenic shock, and cardiac arrest but does not appear to increase the likelihood of stroke/TIA. While this suggest worse outcomes in the cohort undergoing both procedures, the initial indications for these patients to receive a PCI might predispose them to these outcomes.

Funding Acknowledgement

Type of funding source: None

Relationship between falls and Fall Risk Increasing Drugs. A retrospective case control study

Background

Falls and fall-related injuries are a major public health issue which needs global attention due to its clinical and socioeconomic impact. Inpatient falls are the most common adverse event in hospital. Important risk factors for falls are polypharmacy and the assumption of so-called Fall Risk Increasing Drugs (FRIDs). Aims of our study were to investigate the associations between falls and the use of medications among inpatients by conducting a retrospective case-control study in a rehabilitation hospital in Northern Italy in 2018.

Methods

Three unique control for each faller, matched by age, sex and hospitalization ward, were selected. A Conditional Logistic Regression was performed to analyze the impact that 13 types of FRIDs individually and the number of administrated FRIDs had on the risk of falling. A second regression model was obtained adjusting the case-control matching for CIRS, Morse and Barthel scores.

Results

We identified 148 cases and 444 controls. 3 types of FRIDs were significantly correlated (p &lt; 0,05) with an increased risk of falling: Antipsychotics [OR:1,98;CI 95%:1,01-3,89], Antidepressants [OR:2,18;CI 95%:1,32-3,59], Diuretics [OR:1,71;CI 95%:1,09-2,68]. Antidepressants were the only type of FRID significantly correlated (p = 0,008) even in the model adjusted for CIRS, Morse and Barthel scores [OR:2,00;CI 95%:1,20-3,34]. The unadjusted model showed that the addition of one type of FRID to therapy was significantly associated with the fall event (p &lt; 0.05) [OR:1.21;CI 95%: 1.05 - 1.40].

Conclusions

Assumption of drugs and polypharmacy could play a role in hospital falling. Recently developed fall risk assessment tools suffer from low specificity and sensitivity and do not assess these risk factors. A holistic approach with a multidimensional evaluation of the patient through screening tools, functional assessment tools and a full medical evaluation should be improved.

Key messages

Drugs may represent an important variable in determining the risk of falls in hospitalized patients, but they should not be considered alone. Screening tools for fall risk should take into account polypharmacy such as other intrinsic and extrinsic risk factors within an holistic approach.

Metabolite-Based Modification of Poly(l-lysine) for Improved Gene Delivery

Synthetic gene delivery systems employ multiple functions to enable safe and effective transport of DNA to target cells. Here, we describe metabolite-based poly(l-lysine) (PLL) modifiers that improve transfection by imparting both pH buffering and nanoparticle stabilization functions within a single molecular unit. PLL modifiers were based on morpholine (M), morpholine and niacin (MN), or thiomorpholine (TM). PLL modification with (MN) or (TM) imparted buffering function over the pH range of 5-7 both in solution and live cells and enhanced the stability of PLL DNA nanoparticles, which exhibited higher resistance to polyanion exchange and prolonged blood circulation. These properties translated into increased transfection efficiency in vitro coupled with reduced toxicity compared to unmodified PLL and PLL(M). Furthermore, PEG-PLL(MN) DNA nanoparticles transfected muscle tissue in vivo for >45 days following intramuscular injection. These polymer modifiers demonstrate the successful design of multifunctional units that improve transfection of synthetic gene delivery systems while maintaining biocompatibility.

ODF1, sperm flagelar protein is expressed in kidney collecting ducts of rats

ODF1 has been described as an exclusively expressed testicular protein and is located in the outer dense fibers along the sperm tail. ODF1 has been involved in the sperm motility and in the development of the flagellum, but the function of ODF1 is not already clear. Other ODF proteins, such as ODF2 have been characterized in other tissues like the basal body of the kidney primary cilium, but so far only the mRNA of ODF1 has been described in other tissues. These observations let us to hypothesize that the expression of the protein ODF1 could not be limited to the testis. Therefore, in the present work we proposed to evaluate if the ODF1 protein could also be present in tissues other than the testis. Here we demonstrated through western blot, immunofluorescence, and RT-PCR techniques that the protein and mRNA of ODF1 have been identified in the rat kidney. Finally, the presence of ODF1 in kidney has also been confirmed through proteomic analysis using mass spectrometry. The results derived from these different complementary approaches indicate that, to our knowledge and for the first time, ODF1 is demonstrated to be present in an additional organ different to testis. This results raise new questions about potential other functions and locations of the ODF1 protein.

Development of a new high sensitivity mechanical switch for augmentative and alternative communication access in people with amyotrophic lateral sclerosis

BACKGROUND

People with Amyotrophic Lateral Sclerosis (PwALS) in the advanced phase are critically affected by an almost total loss of mobility and severe communication problems. Scanning access based on the patient's interaction with a sensor (or switch) that intercepts even a weak body movement is a valid communication aid. However, its use becomes limited with the progressive decline of residual movements. To overcome this problem, we designed a new sensor, the Lever Magnetic-spring Mechanical Switch (LeMMS), allowing repeated activation/release cycles requiring a very small activation force.

METHODS

The LeMMS was applied and validated in a group of 20 PwALS in an advanced stage of disease. All subjects were regular users of communication aids employing other sensors, but which they could no longer operate their sensors (different from LeMMS). Patients were assessed at baseline (t0) and after one (t1), 6 (t2) and 12 (t3) months. Assessment at t0 included administration of standardized clinical scales, the Click-Test-30 counting the maximum number of LeMMS activations in 30 s, and thumb/fingers strength assessment with the Kendall scale. The QUEST 2.0-Dev questionnaire was administered at t1. Some use-related information and the Click-Test-30 were collected at t1, t2 and t3.

RESULTS

After one training session, all patients could operate the LeMMS with minimal residual movement of one finger. At t1, they used it on average 5.45 h/day. The mean score of the QUEST 2.0-Dev was 4.63, suggesting strong satisfaction with the LeMMS. Regarding Click-Test-30 scores, no significant difference was found between t0 and t1, but performance at t2 and t3 declined significantly (p < 0.005 vs. t0). At t3, 9/20 patients were still able to use their communication aid.

CONCLUSIONS

This new switch sensor can enable PwALS to use their communication aids for a prolonged time even in the advanced phase of disease. It is easy to use, reliable and cheap, thus representing an intermediate alternative to more sophisticated and costly devices.

Integrated veterinary-medical activity on characterization of shigatoxin producing Escherichia coli

Background

Shiga toxin-producing Escherichia coli (STEC) are an important public health concern as they cause severe conditions (bloody diarrhea and hemolytic uremic syndrome - HUS) and have epidemic potential. Cattle are the main reservoir for the highly virulent STEC O157 strain, and other HUS-associated non-O157 strains. This study aimed to characterize strains from animals and humans and to compare their molecular profiles. Animal isolates were tested for the presence of virulence factors correlated to their pathogenic potential.

Methods

74 STEC human isolates from 43 clinical cases (sporadic or epidemic) and 270 animal isolates from feces from 62 cattle farms were collected. Epidemiological investigation to collect environmental and suspected food samples was carried out for 22 cases. All isolates were typed with PFGE and their serotype was defined by Real-Time PCR. Animal isolates were also tested for the presence of subAB, saa, tia, cfk, adfO, hlyA, efaI1-lifA5’3’, and toxB virulence genes.

Results

O157 was detected in 44% of human cases, other relevant serogroups O26, O111, O103, O145 in 21, 9, 5 and 5% of cases, respectively. The source of infection was identified in one case (cheese contaminated by a O157 strain). Among animal isolates 2, 0.7, 0.7 and 0.3% were identified as O157, O11, O113, and O145, respectively. PFGE highlighted a high heterogeneicity among animal strains, however no pulsotype common to cattle and clinical isolates was found. adfO, cfk, efaI1-lifA5’3’ and toxB were found significantly correlated to eae (intimin).

Conclusions

Human and cattle strains were not correlated, however STEC diversity in cattle was very high and included some strains potentially pathogenic to humans. For this reason, upholding an integrated surveillance is very important.

Key messages

Serotypes relevant to human health were found in cattle in a small but not negligible frequence. No direct correlation was found between animal and clinical isolates.

PTPRT epigenetic silencing defines lung cancer with STAT3 activation and can direct STAT3 targeted therapies

Signal Transducers and Activators of Transcription-3 (STAT3), a potent oncogenic transcription factor, is constitutively activated in lung cancer, but mutations in pathway genes are infrequent. Protein Tyrosine Phosphatase Receptor-T (PTPRT) is an endogenous inhibitor of STAT3 and PTPRT loss-of-function represents one potential mechanism of STAT3 hyperactivation as observed in other malignancies. We determined the role of PTPRT promoter methylation and sensitivity to STAT3 pathway inhibitors in non-small cell lung cancer (NSCLC). TCGA and Pittsburgh lung cancer cohort methylation data revealed hypermethylation of PTPRT associated with diminished mRNA expression in a subset of NSCLC patients. We report frequent hypermethylation of the PTPRT promoter which correlates with transcriptional silencing of PTPRT and increased STAT3 phosphorylation (Y705) as determined by methylation-specific PCR (MSP) and real time quantitative reverse transcription (RT)-PCR in NSCLC cell lines. Silencing of PTPRT using siRNA in H520 lung cancer cell line resulted in increased pSTAT3_Tyr705 and upregulation of STAT3 target genes such as Cyclin D1 and Bcl-X_L expression. We show this association of PRPRT methylation with upregulation of the STAT3 target genes Cyclin D1 and Bcl-X_L in patient derived lung tumour samples. We further demonstrate that PTPRT promoter methylation associated with different levels of pSTAT3_Ty705 in lung cancer cell lines had selective sensitivity to STAT3 pathway small molecule inhibitors (SID 864,669 and SID 4,248,543). Our data strongly suggest that silencing of PTPRT by promoter hypermethylation is an important mechanism of STAT3 hyperactivation and targeting STAT3 may be an effective approach for the development of new lung cancer therapeutics.

The SonicHand Protocol for Rehabilitation of Hand Motor Function: A Validation and Feasibility Study

Musical sonification therapy is a new technique that can reinforce conventional rehabilitation treatments by increasing therapy intensity and engagement through challenging and motivating exercises. The aim of this paper is to evaluate the feasibility and validity of the SonicHand protocol, a new training and assessment method for the rehabilitation of hand function. The study was conducted in 15 healthy individuals and 15 stroke patients. The feasibility of implementation of the training protocol was tested in stroke patients only, who practiced a series of exercises concurrently to music sequences produced by specific movements. The assessment protocol evaluated hand motor performance during pronation/supination, wrist horizontal flexion/extension, and hand grasp without sonification. From hand position data, 15 quantitative parameters were computed evaluating mean velocity, movement smoothness, and angular excursions of hand/fingers. We validated this assessment in terms of its ability to discriminate between patients and healthy subjects, test-retest reliability and concurrent validity with the upper limb section of the Fugl-Meyer scale (FM), the functional independence measure (FIM), and the Box and Block Test (BBT). All patients showed a good understanding of the assigned tasks and were able to correctly execute the proposed training protocol, confirming its feasibility. A moderate-to-excellent intraclass correlation coefficient was found in 8/15 computed parameters. The moderate-to-strong correlation was found between the measured parameters and the clinical scales. The SonicHand training protocol is feasible and the assessment protocol showed good to excellent between-group discrimination ability, reliability, and concurrent validity, thus enabling the implementation of new personalized and motivating training programs employing sonification for the rehabilitation of hand function.

Optimization of Phenyl Indole Inhibitors of the AAA+ ATPase p97

Optimization of the side-chain of a phenyl indole scaffold identified from a high-throughput screening campaign for inhibitors of the AAA+ ATPase p97 is reported. The addition of an N-alkyl piperazine led to high potency of this series in a biochemical assay, activity in cell-based assays, and excellent pharmaceutical properties. Molecular modeling based on a subsequently obtained cryo-EM structure of p97 in complex with a phenyl indole was used to rationalize the potency of these allosteric inhibitors.

Predictors of oncological outcomes in T1G3 patients treated with BCG who undergo radical cystectomy

PURPOSE

To evaluate the oncological impact of postponing radical cystectomy (RC) to allow further conservative therapies prior to progression in a large multicentre retrospective cohort of T1-HG/G3 patients initially treated with BCG.

METHODS

According to the time of RC, the population was divided into 3 groups: patients who did not progress to muscle-invasive disease, patients who progressed before radical cystectomy and patients who experienced progression at the time of radical cystectomy. Clinical and pathological outcomes were compared across the three groups.

RESULTS

Of 2451 patients, 509 (20.8%) underwent RC. Patients with tumors > 3 cm or with CIS had earlier cystectomies (HR = 1.79, p = 0.001 and HR = 1.53, p = 0.02, respectively). Patients with tumors > 3 cm, multiple tumors or CIS had earlier T3/T4 or N + cystectomies. In patients who progressed, the timing of cystectomy did not affect the risk of T3/T4 or N + disease at RC. Patients with T3/T4 or N + disease at RC had a shorter disease-specific survival (HR = 4.38, p < 0.001), as did patients with CIS at cystectomy (HR = 2.39, p < 0.001). Patients who progressed prior to cystectomy had a shorter disease-specific survival than patients for whom progression was only detected at cystectomy (HR = 0.58, p = 0.024) CONCLUSIONS: Patients treated with RC before experiencing progression to muscle-invasive disease harbor better oncological and survival outcomes compared to those who progressed before RC and to those upstaged at surgery. Tumor size and concomitant CIS at diagnosis are the main predictors of surgical treatment while tumor size, CIS and tumor multiplicity are associated with extravesical disease at surgery.

A threonine turnstile defines a dynamic amphiphilic binding motif in the AAA ATPase p97 allosteric binding site

The turnstile motion of two neighboring threonines sets up a dynamic side chain interplay that can accommodate both polar and apolar ligands in a small molecule allosteric protein binding site. A computational model based on SAR data and both X-ray and cryo-EM structures of the AAA ATPase p97 was used to analyze the effects of paired threonines at the inhibitor site. Specifically, the Thr side chain hydroxyl groups form a hydrogen bonding network that readily accommodates small, highly polar ligand substituents. Conversely, diametric rotation of the χ₁ torsion by 150-180° orients the side chain β-methyl groups into the binding cleft, creating a hydrophobic pocket that can accommodate small, apolar substituents. This motif was found to be critical for rationalizing the affinities of a structurally focused set of inhibitors of p97 covering a > 2000-fold variation in potencies, with a preference for either small-highly polar or small-apolar groups. The threonine turnstile motif was further validated by a PDB search that identified analogous binding modes in ligand interactions in PKB, as well as by an analysis of NMR structures demonstrating additional gear-like interactions between adjacent Thr pairs. Combined, these data suggest that the threonine turnstile motif may be a general feature of interest in protein binding pockets.

Bidialysis: A new Technique

An increase in solute removal, a shorter dialysis session, the patient's well being and the reduction of global costs are the principal aims of the new hemodialysis methods. The simultaneous use of two hemodialyzers in hemodialysis has been experimented by other researchers. Our technique involves the use of two cuprophan hemodialyzers in sequence (double filter system: DFS), each one connected separately to fresh dialysate.

Fifteen symptomatic large patients were treated with DFS and the results were compared to conventional hemodialysis (CHD). After the first hemodialyzer, modification of pH and electrolytes occurred in the plasma composition. In the second hemodialyzer, urea depuration occurred without further significant changes in hydroelectrolytic or acid-basic plasma patterns. The Kt/V increased from 1.10 to 1.29 (18%).

The authors conclude that in DFS there was an advantage in urea clearance, osmolarity stability and reduction of side effects.