Autoantibodies detection in patients affected by autoimmune retinopathies

OBJECTIVE

Autoimmune retinopathies (ARs) encompass a spectrum of immune diseases that are characterized by the presence of autoantibodies against retinal proteins in the bloodstream. These autoantibodies (AAbs) lead to a progressive and sometimes rapid loss of vision. ARs commonly affect subjects over 50 years of age, but also rare cases of kids under 3 years of age have been reported.

PATIENTS AND METHODS

In this study, 47 unrelated Caucasian patients were enrolled. All subjects showed negative cancer diagnoses and negative results in their genetic screenings. We studied 8 confirmed retinal antigens using Western blotting analysis, with α-enolase followed by carbonic anhydrase II being the two most frequently found in the patients' sera.

RESULTS

Nineteen patients were positive (40.4%), thirteen uncertain (27.7%), and fifteen were negative (31.9%). Their gender did not correlate with the presence of AAbs (p=0.409).

CONCLUSIONS

AAbs are responsible for retinal degeneration in some cases, while in others, they contribute to exacerbating the progression of the disease; however, their detection is crucial to reaching a better diagnosis and developing more effective treatments for these conditions. Moreover, finding good biomarkers is important not only for AR monitoring and prognosis, but also for helping with early cancer diagnosis.

Therapy-Related Myeloid Neoplasms: Predisposition and Clonal Evolution

Therapy-related Myeloid Neoplasm (t-MN) represents one of the worst long-term consequences of cytotoxic therapy for primary tumors and autoimmune disease. Poor survival and refractoriness to current treatment strategies characterize affected patients from a clinical point of view. In our aging societies, where newer therapies and ameliorated cancer management protocols are improving the life expectancy of cancer patients, therapy-related Myeloid Neoplasms are an emerging problem. Although several research groups have contributed to characterizing the main risk factors in t-MN development, the multiplicity of primary tumors, in association with the different therapeutic strategies available and the new drugs in development, make interpreting the current data still complex. The main risk factors involved in t-MN pathogenesis can be subgrouped into patient-specific, inherited, and acquired predispositions. Although t-MN can occur at any age, the risk tends to increase with advancing age, and older patients, characterized by a higher number of comorbidities, are more likely to develop the disease. Thanks to the availability of deep sequencing techniques, germline variants have been reported in 15-20% of t-MN patients, highlighting their role in cancer predisposition. It is becoming increasingly evident that t-MN with driver gene mutations may arise in the background of Clonal Hematopoiesis of Indeterminate Potential (CHIP) under the positive selective pressure of chemo and/or radiation therapies. Although CHIP is generally considered benign, it has been associated with an increased risk of t-MN. In this context, the phenomenon of clonal evolution may be described as a dynamic process of expansion of preexisting clones, with or without acquisition of additional genetic alterations, that, by favoring the proliferation of more aggressive and/or resistant clones, may play a crucial role in the progression from preleukemic states to t-MN.

Cleaning Up without Messing Up: Maximizing the Benefits of Plastic Clean-Up Technologies through New Regulatory Approaches

As the global plastics crisis grows, numerous technologies have been invented and implemented to recover plastic pollution from the environment. Although laudable, unregulated clean-up technologies may be inefficient and have unintended negative consequences on ecosystems, for example, through bycatch or removal of organic matter important for ecosystem functions. Despite these concerns, plastic clean-up technologies can play an important role in reducing litter in the environment. As the United Nations Environment Assembly is moving toward an international, legally binding treaty to address plastic pollution by 2024, the implementation of plastic clean-up technologies should be regulated to secure their net benefits and avoid unintended damages. Regulation can require environmental impact assessments and life cycle analysis to be conducted predeployment on a case-by-case basis to determine their effectiveness and impact and secure environmentally sound management. During operations catch-efficiency and bycatch of nonlitter items, as well as waste management of recovered litter, should be documented. Data collection for monitoring, research, and outreach to mitigate plastic pollution is recommended as added value of implementation of clean-up technologies.

A comprehensive assessment of plastic remediation technologies

The global presence of plastic litter and its accumulation in the environment has become an issue of concern to the public and policymakers. This concern has triggered innovators in past decades to design and develop a multitude of remediation technologies to prevent plastic from entering the environment, or to clean up legacy litter. This study aims to (i) systematically review the current scientific literature on plastic remediation technologies, (ii) create a 'plastic clean-up and prevention overview' illustrating 124 remediation technologies and 29 characteristics, (iii) qualitatively analyse their key characteristics (e.g., fields of application, targeted plastic), and (iv) investigate challenges and opportunities of clean-up technologies for inland waterways (e.g., canals, rivers) and ports. We identified 61 scientific publications on plastic remediation technologies, until June 2022. Thirty-four of these studies were published within the last three years, demonstrating a growing interest. The presented overview indicates that inland waterways are, so far, the preferred field of application, with 22 technologies specifically designed for cleaning up plastics from inland waterways, and 52 additional ones with the potential to be installed in these locations. Given the importance of clean-up technologies in inland waterways, we highlighted their strengths, weaknesses, opportunities, and threats (SWOT). Our results indicate that, despite the challenges, these technologies provide essential prospects, from improving the environmental quality to raising awareness. Our study is instrumental as it illustrates an up-to-date overview and provides a comprehensive analysis of current in design phase, testing, and in use plastic remediation technologies.

Integrating Bayesian Belief Networks in a toolbox for decision support on plastic clean-up technologies in rivers and estuaries

Current mitigation strategies to offset marine plastic pollution, a global concern, typically rely on preventing floating debris from reaching coastal ecosystems. Specifically, clean-up technologies are designed to collect plastics by removing debris from the aquatic environment such as rivers and estuaries. However, to date, there is little published data on their potential impact on riverine and estuarine organisms and ecosystems. Multiple parameters might play a role in the chances of biota and organic debris being unintentionally caught within a mechanical clean-up system, but their exact contribution to a potential impact is unknown. Here, we identified four clusters of parameters that can potentially determine the bycatch: (i) the environmental conditions in which the clean-up system is deployed, (ii) the traits of the biota the system interacts with, (iii) the traits of plastic items present in the system, and, (iv) the design and operation of the clean-up mechanism itself. To efficiently quantify and assess the influence of each of the clusters on bycatch, we suggest the use of transparent and objective tools. In particular, we discuss the use of Bayesian Belief Networks (BBNs) as a promising probabilistic modelling method for an evidence-based trade-off between removal efficiency and bycatch. We argue that BBN probabilistic models are a valuable tool to assist stakeholders, prior to the deployment of any clean-up technology, in selecting the best-suited mechanism to collect floating plastic debris while managing potential adverse effects on the ecosystem.

POS1316 VISUAL FUNCTION AND QUALITY OF LIFE: PRELIMINARY RESULTS FROM A PIVOTAL CROSS-SECTIONAL STUDY ON ONE HUNDRED PATIENTS WITH JUVENILE IDIOPATHIC ARTHRITIS-ASSOCIATED AND IDIOPATHIC UVEITIS

Background:

Juvenile idiopathic arthritis (JIA) is the main cause of chronic uveitis in childhood and JIA associated uveitis (JIA-U) is the most common extraarticular complication of JIA. Despite continuous improvement in its management, pediatric uveitis still represents a serious condition with potential sight-threatening complications and a significant impact on quality of life (QoL).

Objectives:

To evaluate visual function (VF) and QoL in children with JIA-U and idiopathic uveitis

Methods:

A cross-sectional study was conducted in two tertiary Pediatric Rheumatology Centres, enrolling all patients seen with JIA-U, JIA without uveitis and idiopathic uveitis. VF was assessed by a translated form of the available EYE-Q, adapted for cross-cultural feasibility into a 10-question tool, while QoL was evaluated by the Italian version of the Pediatric Rheumatology Quality of Life scale part of the Juvenile Arthritis Multidimensional Report (JAMAR), shortened for feasibility to a 8-question tool. JAMAR section on treatment compliance and school attendance was also included. Parents, and patients when appropriate, were asked to complete each patient/parent-reporting outcome measure, answering on a 4-point Likert scale, with a total score ranging from 0 to 72 (worst condition). Medical charts were reviewed regarding JIA and uveitis features and outcome. Quantitative and qualitative variables were compared by means of Mann-Whitney U test or chi-square/Fisher exact test, as appropriate; correlations among quantitative non-parametric variables were evaluated by Spearman’s test.

Results:

We herein describe results from the first 100 patients enrolled (76% female), with a median age at study time of 12.8 (9.0-17.6) years. Forty-nine had JIA-U, 37 JIA without uveitis and 14 idiopathic uveitis. Uveitis was active in 14/63 patients (22.2%), with a median of uveitis duration of 9.0 years (3.6-14.8). Almost all children with uveitis were on systemic treatment (58/63, 92%) at the time of interview; 54.0% of patients presented an ocular damage, with 8.0% having a best corrected visual acuity (BCVA) < 4/10. Total score, VF and QoL scores resulted significantly higher in JIA-U patients compared to JIA without uveitis, while no differences were noticed among children with uveitis with or without JIA (Table 1). School absence was reported more frequently in JIA-U compared to JIA only (32.7% vs 10.8%, p 0.0211). VF was significantly worse in patients with ocular damage and BCVA < 4/10 (p 0.0351 and 0.0123, respectively). In patients with uveitis, VF and QoL showed a significant correlation (r 0.50, p <0.0001) especially in patients with idiopathic uveitis (r 0.74, p <0.0001).

Conclusion:

Visual function is a crucial component of QoL in children with uveitis and it correlates with ocular damage. Since eye involvement significantly affect QoL in patients with JIA, a specific tool widely validated and cross-cultural adapted is highly demanded in the clinical care of JIA-U patients.

References:

[1]Angeles-Han ST et al. The importance of visual function in the quality of life of children with uveitis. J AAPOS, 2010. Filocamo et al. A New Approach to Clinical Care of Juvenile Idiopathic Arthritis: The Juvenile Arthritis Multidimensional Assessment Report. J Rheumatol, 2011.

Table 1.JIA-Un = 49Idiopathic uveitisn = 14JIAn = 37p-value*p-value#Total score5.0 (3.0-11.0)4.5(2-9.8)2.0(0-4.0)0.5739<0.0001VF score2.0 (0-3.0)1.0(0-3.0)0(0-0)0.9098<0.0001QoL score3.0(2.0-6.0)3.5(2.0-4.8)2.0(0-4.0)0.56110.0005

Numbers are medians (IQR). * JIA-U vs idiopathic uveitis; #JIA-U vs JIA

Disclosure of Interests:

None declared

POS1317 PREDICTIVE FACTORS FOR RESPONSE TO TREATMENT IN A LONG-TERM COHORT OF PATIENTS WITH JUVENILE IDIOPATHIC ARTHRITIS-ASSOCIATED UVEITIS

Background:

Uveitis is the main extraarticular complication of juvenile idiopathic arthritis (JIA) with still a significant impact on JIA morbidity, despite continuous improvement in systemic treatment. Although antinuclear antibody positivity and early onset of JIA have been associated with a high risk of uveitis onset, so far no clinical features have been widely recognized as predictive factors for JIA-associated uveitis (JIA-U) response to treatment.

Objectives:

To investigate clinical features associated with response to systemic treatment in a long-term cohort of patients with JIA-U

Methods:

Clinical records of patients with JIA-U were retrospectively reviewed with regard to clinical features, therapeutic choices and outcome. Clinical and laboratory variables were compared by means of Mann-Whitney U test or chi-square/Fisher exact test, as appropriate.

Results:

Data from 164 JIA-U patients were analysed (81.7% female), with a median follow up of 12.1 years (7.1-17.3). Median age at JIA and uveitis onset was 2.6 (1.6-4.8) and 4.8 (2.9 – 7.0) years, respectively. Monotherapy with a conventional disease-modifying antirheumatic drug (DMARD) was used in 25.0% of patients, while 111 patients (67.7%) received at least one biologic DMARD (bDMARDs). Compared to patients responsive to DMARDs, children requiring a bDMARDs for uveitis had a lower median age at both JIA (2.4 vs 4.3 years, p 0.0234) and uveitis onset (4.1 vs 6.2 years, p 0.0023). Despite no differences in ocular damage at onset and median disease duration, patients not responsive to conventional DMARDs showed a higher frequency of ocular damage at the last visit (66.2% vs 33.3%, p 0.011). Children requiring more than one bDMARD for uveitis presented a more frequent polyarticular course (87.0% vs 20.2%, p 0.0022), a longer disease duration (median follow-up: 14.2 vs 10.4 years, p 0.0397) and a higher frequency of visual loss (best corrected visual acuity < 4/10: 23.3% vs 6.3%, p 0.0069).

Conclusion:

JIA-U patients with a lack of response to conventional DMARDs were significantly younger both at JIA and uveitis onset. Severe JIA-U requiring more than one bDMARDs was associated with polyarticular JIA course and longer disease duration. Children resistant to conventional treatment need prompt recognition and additional strategies to improve long-term outcome.

References:

[1]Heiligenhaus et al. Predictive factors and biomarkers for the 2-year outcome of uveitis in juvenile idiopathic arthritis. Rheumatology 2019.

Disclosure of Interests:

None declared

Patterns of ectoparasite infection in wild-caught and laboratory-bred cichlid fish, and their hybrids, implicate extrinsic rather than intrinsic causes of species differences in infection

Parasite-mediated selection may initiate or enhance differentiation between host populations that are exposed to different parasite infections. Variation in infection among populations may result from differences in host ecology (thereby exposure to certain parasites) and/or intrinsic immunological traits. Species of cichlid fish, even when recently diverged, often differ in parasite infection, but the contributions of intrinsic and extrinsic causes are unknown. Here, we compare infection patterns between two closely related host species from Lake Victoria (genus Pundamilia), using wild-caught and first-generation laboratory-reared fish, as well as laboratory-reared hybrids. Three of the commonest ectoparasite species observed in the wild were also present in the laboratory populations. However, the infection differences between the host species as observed in the wild were not maintained in laboratory conditions. In addition, hybrids did not differ in infection from either parental species. These findings suggest that the observed species differences in infection in the wild might be mainly driven by ecology-related effects (i.e. differential exposure), rather than by intrinsic species differences in immunological traits. Thus, while there is scope for parasite-mediated selection in Pundamilia in the wild, it has apparently not yet generated divergent evolutionary responses and may not enhance assortative mating among closely related species.

Photoprotection of the future: challenges and opportunities

The use of sunscreens is an important and essential component of photoprotection. Since their introduction during the first half of the last century, sunscreens have benefited enormously from major technological advances such as the development of novel UV filters; as a result, their efficacy in preventing UV-induced erythema is unequivocal. More recently, however, new challenges have appeared, which have prompted a robust discussion about the safety of sunscreens. These include topics directly related to photoprotection of human skin such as improved/alternative methods for standardization of assessment of the efficacy of sunscreens, but also many others such as photoprotection beyond UV, concerns about human toxicity and ecological safety, the potential of oral photoprotective measures, consequences of innovative galenic formulations. On a first glance, some of these might raise questions and doubts among dermatologists, physicians and the general public about the use sunscreens as a means of photoprotection. This situation has prompted us to critically review such challenges, but also opportunities, based on existing scientific evidence. We conclude by providing our vision about how such challenges can be met best in the future in an attempt to create the ideal sunscreen, which should provide adequate and balanced protection and be easy and safe to use.

Deficiencies in health-related quality-of-life assessment and reporting: a systematic review of oncology randomized phase III trials published between 2012 and 2016

Quality of life (QoL) is a relevant end point and a topic of growing interest by both scientific community and regulatory authorities. Our aim was to review QoL prevalence as an end point in cancer phase III trials published in major journals and to evaluate QoL reporting deficiencies in terms of under-reporting and delay of publication. All issues published between 2012 and 2016 by 11 major journals were hand-searched for primary publications of phase III trials in adult patients with solid tumors. Information about end points was derived from paper and study protocol, when available. Secondary QoL publications were searched in PubMed. In total, 446 publications were eligible. In 210 (47.1%), QoL was not included among end points. QoL was not an end point in 40.1% of trials in the advanced/metastatic setting, 39.7% of profit trials and 53.6% of non-profit trials. Out of 231 primary publications of trials with QoL as secondary or exploratory end point, QoL results were available in 143 (61.9%). QoL results were absent in 37.6% of publications in the advanced/metastatic setting, in 37.1% of profit trials and 39.3% of non-profit trials. Proportion of trials not including QoL as end point or with missing QoL results was relevant in all tumor types and for all treatment types. Overall, 70 secondary QoL publications were found: for trials without QoL results in the primary publication, probability of secondary publication was 12.5%, 30.9% and 40.3% at 1, 2 and 3 years, respectively. Proportion of trials not reporting QoL results was similar in trials with positive results (36.5%) and with negative results (39.4%), but the probability of secondary publication was higher in positive trials. QoL is not included among end points in a relevant proportion of recently published phase III trials in solid tumors. In addition, QoL results are subject to significant under-reporting and delay in publication.

'High dose' vs. 'medium dose' UVA1 phototherapy in italian patients with severe atopic dermatitis

BACKGROUND

The current evidences attest UVA1 phototherapy as effective in the treatment of severe atopic dermatitis (AD). Furthermore, in this indication, 'medium dose' is as effective as 'high dose' regimen. To date, a randomized comparison study evaluating the effectiveness as well as safety of different UVA1 protocols in different skin types in the treatment of adult patients with severe AD is still lacking.

OBJECTIVE

The aim of the present study was to compare the safety and the efficacy of medium and high dose UVA1 either in fair or in dark skin types.

METHODS

Twenty-seven adult patients with severe AD were consecutively included in a randomized, controlled, open, two arms trial Severity of AD was determined by means of SCORAD index and clinical improvement was also monitored. A total of 13 out of 27 patients were treated with high dose (130 J/cm2 ) UVA1 protocol while 14 out of 27 patients received medium dose (60 J/cm2 ) UVA1 protocol. Phototherapy was performed five times weekly up to 3 weeks. Before and after UVA1 treatment each patient was evaluated for skin pigmentation through Melanin Index (MI) quantitative evaluation.

RESULTS

Skin status improved in all patients resulting in a reduction of SCORAD index in all groups. Our results demonstrated that among patients with darker skin types and higher MI, high dose UVA1 was significantly more effective than medium dose (P < 0.0001) while within the groups with skin type II, no significant differences between high and medium dose protocols were observed.

CONCLUSION

Our study, confirms previous observations that UVA1 phototherapy should be considered among the first approaches in the treatment of patients with severe generalized AD and also demonstrates that in darker skin types, high dose UVA1 phototherapy is more effective than medium dose in the treatment of adult patients with severe AD.

Inducing cancer indolence by targeting mitochondrial Complex I is potentiated by blocking macrophage-mediated adaptive responses

Converting carcinomas in benign oncocytomas has been suggested as a potential anti-cancer strategy. One of the oncocytoma hallmarks is the lack of respiratory complex I (CI). Here we use genetic ablation of this enzyme to induce indolence in two cancer types, and show this is reversed by allowing the stabilization of Hypoxia Inducible Factor-1 alpha (HIF-1α). We further show that on the long run CI-deficient tumors re-adapt to their inability to respond to hypoxia, concordantly with the persistence of human oncocytomas. We demonstrate that CI-deficient tumors survive and carry out angiogenesis, despite their inability to stabilize HIF-1α. Such adaptive response is mediated by tumor associated macrophages, whose blockage improves the effect of CI ablation. Additionally, the simultaneous pharmacological inhibition of CI function through metformin and macrophage infiltration through PLX-3397 impairs tumor growth in vivo in a synergistic manner, setting the basis for an efficient combinatorial adjuvant therapy in clinical trials.

Abstract PD9-11: Platelet derived growth factor receptor-β signaling: A novel therapeutic target for breast cancer associated brain metastasis

PDGFRβ is a receptor tyrosine kinase found in cells of mesenchymal origin such as fibroblasts and pericytes. Activation of this receptor is dependent on paracrine ligand induction, and its preferred ligand, PDGFB, is released by neighboring epithelial and endothelial cells. While expression of both PDGFRβ and PDGFB has been noted in patient breast tumors for decades, how PDGFB-to-PDGFRβ tumor-stromal signaling mediates breast cancer initiation, progression, and metastasis remains unclear. To test this important research question, we developed a mouse model of mesenchymal-specific PDGFRβ hyper-activation. PDGFRβ mutant mammary glands exhibit increased tertiary side-branching and epithelial proliferation confirming a stromal-specific PDGFRβ effect on neighboring epithelium during normal development. To test the effect of hyper-active mesenchymal PDGFRβ on disease progression, experimental tail vein metastasis assays were performed where we observed prominent brain metastases in 50% of the PDGFRβ mutantmice (n=5/10) with no brain lesions seen in controls (n=0/19). There was no difference in the incidence of lung or liver metastases in the mutant mice suggesting a pro-metastatic function for PDGFRβ in the brain metastatic niche. To rule out dysfunction of the blood brain barrier contributing to the observed metastatic spread, we then intracranially injected mammary tumor cells, and as expected based on our metastasis assay, found that larger tumors formed in the brains of PDGFRβ mutant mice versus controls. To our knowledge, these combined findings are the first example where genetic manipulation of the stroma increases breast cancer associated brain metastases (BCBM). Given that these pre-clinical data suggest that primary breast tumors expressing high PDGFB could preferentially metastasize to the brain, we analyzed PDGFB protein expression in a tissue microarray comprised of HER2-positive and triple negative breast cancer (TNBC) primary tumors (total n=425). While high PDGFB did not correlate with site-independent metastatic recurrence, it was prognostic of brain metastasis, mirroring our mouse data. Evaluation of PDGFB in a small cohort of matched primary breast tumors with associated brain (n=5) and lung metastases (n=2) revealed intense PDGFB staining in 100% of the brain metastases, but only 50% of the lung metastases. These findings further suggest that high primary tumor PDGFBexpression defines a subset of breast cancer patients predisposed to brain metastases and that these patients may benefit from therapeutic inhibition of PDGFRβ signaling. To test this pre-clinically, we treated mice harboring intracranial tumors with the PDGFR specific inhibitor crenolanib. Excitingly, crenolanib treatment significantly inhibited the brain tumor burden in these mice. Combined, our findings to date (1) advocate that primary tumor expression of PDGFB is a novel prognostic biomarker for the development of BCBM and (2) support clinical trial evaluation of PDGFR inhibitors for the prevention and treatment of BCBM. Ongoing studies are evaluating how the PDGFRβ-expressing mesenchymal cells within the brain promote a pro-metastatic niche.

Citation Format: Sizemore GM, Hammer AM, Thies KA, Hildreth BE, Russell LO, Sizemore ST, Trimboli AJ, Kladney RD, Steck SA, Das M, Bolyard CM, Pilarski R, Schoenfield L, Otero J, Chakravarti A, Ringel M, Kaur B, Leone G, Ostrowski MC. Platelet derived growth factor receptor-β signaling: A novel therapeutic target for breast cancer associated brain metastasis [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD9-11.

Ovarian Granulocytic Sarcoma with Central Nervous System Involvement

The authors describe 2 cases of acute myeloid leukemia (AML) with ovarian granulocytic sarcoma (GS) and central nervous system (CNS) involvement. The patients had an unfavorable clinical course in a short period of time. It has been reported that GS or CNS involvement does not have a bad prognostic significance. We suggest that the association of these two complications worsens the prognosis of AML.

Clinical Manifestations and Management of Inherited Thrombophilia: Retrospective Analysis and Follow-up after Diagnosis of 238 Patients with Congenital Deficiency of Antithrombin III, Protein C, Protein S

The clinical history of 238 patients with inherited thrombophilia (AT III = 94, PC = 103, PS = 41) was analyzed retrospectively at diagnosis and in the follow-up period after diagnosis. At diagnosis 129 patients (54%) had suffered from thrombosis, with a recurrence rate of 48%. The most frequent onset manifestation was deep vein thrombosis of lower limbs (58%). Thrombotic history started before 40 in 80% of the cases. Forty-nine percent of the venous thromboses were preceded by a triggering event, in most cases pregnancy (17%) and surgery (12%). After diagnosis, follow-up lasted a total of 1,113 pt-years. A policy of short-term prophylaxis during risk situations for all patients and long-term prophylaxis in symptomatic patients failed to prevent venous thrombotic episodes (diagnosed by objective methods) in 4 previously asymptomatic subjects and recurrence in 7 previously symptomatic subjects. After knowledge of the patients’ diagnosis the incidence of venous thrombosis/100 pt-years was reduced as compared before diagnosis as total episodes (onset + recurrencies) (1.0 vs 1.9), onset episodes (0.7 vs 1.3) and recurrent episodes (1.3 vs 4.8), even though the differences were not statistically significant. However most of the venous thromboses occurred at a more advanced age (67% after 40 years) and without any apparent cause (83%), at significant variance with the period preceding the diagnosis; in particular the incidence of venous thrombotic onset in patients younger than 40 passed from 1.3/100 pt-years to 0.2/100 pt-years. In 6 recurrences after diagnosis a poor compliance for antithrombotic treatment was recognized. We conclude that a policy based on knowledge of diagnosis and on the implementation of antithrombotic treatment during risk situations appears to modify the clinical outcome of deficiencies of natural anticoagulants even in the absence of long-term antithrombotic prophylaxis; in particular morbidity of young patients is significantly reduced.

Instrument Effect on the Activated Protein C Resistance Plasma Assay Performed by a Commercial Kit

In order to evaluate the influence of the coagulation instrument on the activated protein C (APC)-resistance plasma assay performed by a commercial kit, we tested 70 plasma samples on 4 different instruments during a simultaneous session run using a same lot of Coatest APC-resistance (Chromogenix). The results were analyzed employing three different modes of expression (aPTT prolongation in the presence of APC, APC-sensitivity ratio, normalized APC-sensitivity ratio) and three different diagnostic threshold values (below the control mean −2 standard deviations or the lowest control value or the 5th percentile of the control values). The inter-instruments variability in the mean values of the control individuals can be limited expressing the results as nor-malized-APC-sensitivity ratio (range 0.99-1.05). The overall diagnostic yield in thrombotic patients and their relatives depended mainly on the instrument employed and only in some cases on the mode of expression of the results and on the diagnostic threshold value. The sensitivity of the commercial assay on heterozygotes for factor V Leiden diagnosed by gene analysis was overall satisfactory (75-100%) but in some cases a lower diagnostic yield was noticed, depending on the type of instrument employed and/or the type of expression of the results and/or the diagnostic threshold values. Thus the instrument system adopted should be carefully considered in the interpretation of the results using the commercial kit.

Antithrombin III in Full-Term and Pre-Term Newborn Infants : Three Cases of Neonatal Diagnosis of AT III Congenital Defect

Antithrombin III (AT III) plasma levels were investigated in 18 full term neonates and 14 healthy preterm neonates. A control group of 20 healthy adults was also studied. AT III was measured as antigen concentration (Ag) and antithrombin or anti-factor Xa heparin cofactor (H. C.) activities. Crossed immunoelectrophoresis on heparin-agarose (H-CIE) was carried out on plasma samples; moreover the distribution of isoantithrombins was investigated on whole plasma by a technique of crossed immunoelectrofocusing (CIEF). AT III plasma levels in full term infants were significantly lower as compared to the adult values. The preterm newborns group showed a further significant decrease in AT III levels as compared to the full term neonates. In all infants AT III H-CIE runs displayed a single fast moving anodal peak, so that a normal binding to heparin was demonstrated. The CIEF AT III plasma pattern of the adults as well as of all neonates displayed three major peaks at pH range 5.2-4.9, a small amount of AT III at pH 4.9-4.8 and a minor peak at pH 4.8-4.6, so that it was concluded that the isoantithrombins plasma distribution in neonatal age is identical to that of the adult subjects. Four neonates whose mothers were affected by AT III congenital defect were also investigated: diagnosis of congenital deficiency was established in three cases.

Replacement Therapy with a Purified Protein C Concentrate during Initiation of Oral Anticoagulation in Severe Protein C Congenital Deficiency

The case of an adult patient with moderately severe protein C deficiency (antigen 16%, activity 12%) is reported. Both parents had protein C levels compatible with heterozygous deficiency. Unlike other reported cases of severe protein C deficiency in adults, the onset of thrombotic symptoms occurred at 1 month of age; however, a symptom-free period until age 17 followed. Replacement therapy with a monoclonal antibody purified protein C concentrate was carried out during the initiation of oral anticoagulation after a course of i.v. heparin for deep vein thrombosis. The administration of the concentrate allowed maintenance of protein C above 50% until a stable therapeutic anticoagulation level could be obtained. This was reached within a short time, thus allowing safe administration of a loading dose of warfarin. We conclude that this approach to the prevention of skin necrosis seems more rapid and safer than previous schedules of oral anticoagulation in protein C-deficient patients.

Platelet Aggregation by Thimerosal

Thimerosal, a sulphydryl inhibitor, induces aggregation of normal platelet rich plasma over a wide range of concentrations. Low doses induce a monophasic response preceded by a lag phase, high doses produce an immediate biphasic response.

Thimerosal induces platelet aggregation through its binding by sulphydryl groups.

Thimerosal induced aggregation is not mediated by ADP, it is not influenced by fibrinogen, von Willebrand factor, calcium, and magnesium ions of the medium.

Thimerosal induced platelet aggregation is normal in patients affected by thrombocyto-pathia (defect of ADP release) but not in patients affected by Glanzmann’s thrombasthenia. Mercaptopropionglycine, a substance which tends to preserve SH groups, inhibits platelet aggregation induced by thimerosal, thrombin, collagen, and ADP.

A mechanism is proposed for thimerosal induced aggregation and the role of SH groups also in ADP, thrombin and collagen induced aggregation is indicated.

Antithrombin III Molecular Variants with Defective Binding to Heparin or to Serine Proteases: Evidence of Two Different Abnormal Patterns Identified by Crossed Immunoelectrofocusing

Molecular heterogeneity of antithrombin III (AT III) was investigated by a technique of crossed immunoelectrofocusing (CIEF) in plasma samples of patients from 16 families with AT III congenital defect, including 8 AT III molecular variants. The AT III CIEF pattern was normal in all the patients with AT III quantitative deficiency, showing a balanced decrease of all the peaks. Out of the 8 AT III variants investigated, 6 had an abnormal pattern: the three variants with defective binding to heparin (AT III Roma, AT III Barcelona, AT III Malmö) shared a similar abnormal pattern; three variants with defective binding to serine proteases (AT III Pescara, AT III Milano, AT III Tampere) had a common abnormal pattern clearly different from the first one, whereas the other two variants deficient in the inactivation of the serine proteases (AT III Chicago, AT III Milano 2) showed a normal pattern. The first type of pathological pattern (type Roma) was characterized by the presence of an abnormal peak overlapping the normal isoforms present at pH 4.8-4.6 and by an additional peak at pH 4.5. The second type of pattern (type Pescara) showed an additional peak at pH 4.5 and an abnormal quantitative distribution of the isoantithrombins all throughout the pH range (5.2-4.6). In order to separate the abnormal AT III fraction from the normal one, plasma of a patient with Roma defect and serum of a patient with Pescara defect were passed throughout an heparin-ultrogel column. The CIEF of the different AT III Roma and AT III Pescara fractions obtained by affinity chromatography confirmed that the abnormalities found in the corresponding patterns of the native samples were related to the pathological isoantithrombins only. It was concluded that the CIEF can be an useful tool to characterize abnormal antithrombins and can reveal close affinities among AT III molecular variants belonging to different subgroups according to the conventional tests.

Management of Pregnancy in Women with Antithrombin III Congenital Defect: Report of Four Cases

Four pregnant women with antithrombin III congenital deficiency underwent thrombosis prophylaxis including oral antico–agulants administered from the 16–18th week to the 36–37th week of pregnancy, subcutaneous heparin before the 16–18th week and after the 36–37th week, and a single infusion of AT III concentrate in the peripartum period in order to obtain a minimal level of 0.8 U/ml of AT III functional activity. The level of circulating AT III after the concentrate infusion needs to be evaluated by functional methods, because of a consistent amount in the concentrates of inactive AT III immunoreactive material. No thrombotic or haemorrhagic complication occurred after starting prophylaxis in any woman either in any newborn.

Platelet Activation in Patients with Benign and Malignant Ovarian Diseases

Plasma concentration of beta-thromboglobulin (beta-TG) and platelet factor 4 (PF4) were measured by radioimmunoassay in 45 patients with benign and malignant ovarian diseases. All patients with ovarian carcinoma showed increased beta-TG and PF4 levels. Among benign ovarian diseases the patients with serous cystadenoma more frequently showed signs of platelet activation, whereas those with endometriotic cyst and mucinous cystadenoma generally had normal beta-TG and PF4 values. These results indicate that an increased platelet activation is consistently associated with malignant tumors of the ovary, whereas benign tumors show a different capacity to induce platelet activation.

Apparent Isolated Skin Relapse in Acute Monocytic Leukemia. A Case Report

A case of acute monocytic leukemia with an apparent isolated skin relapse is reported. The cutaneous involvement was associated with a morphological bone marrow remission but a cytogenetic relapse was present. Regression of the skin lesions was obtained with a protocol including daunoblastine, aracytin and thioguanine, but the patient relapsed and died a few months later without achieving another remission. The relation between cutaneous and medullary disease is discussed.

Survival after PBSC Transplantation and Comparison of Engraftment Speed with Autologous and Allogeneic Marrow Transplantation: Results of a Multicenter Study

We have analyzed the results of a multicenter study on peripheral blood stem cell transplantation (PBSCT) performed on 55 patients suffering from various neoplastic diseases. After myeloablative therapy, they received a mediam of 6.8x108/kg MNC and 11.4x104/kg CFU-GM harvested by a median of 9 apheresis after mobilization with chemotherapy alone. As of date, 34 of the 55 patients are alive and 28 of them are in continuous complete remission after a follow-up of 30 months. The probability of survival was related to the disease status at transplant, CR/PR vs. PD (p= 0.0001) and the bone marrow involvement, BM-vs. BM+ (P=0.009). Furthermore, a comparative study on speed of engraftment and clinical management was conducted on the 55 PBSCT patients as well as on 41 autoBMT and 52 alloBMT patients. Days to reach WBC> 1.0x109/L, PMN> 0.5x109/L and PLT> 50x109/L was 12/14/33 for PBSCT, 17/20/23 for ABMT and 15/16.5/18 for BMT, respectively. Days with fever >38° C, systemic antibiotic therapy and length of hospitalization was 3/12/36 for PBSCT, 5/18.5/42 for ABMT and 9/25/46 for BMT respectively.

Five-year Experience in PBSC Collection: Results of the Catholic University of Rome

Several authors have reported a faster immunological and hemopoietic post- transplant reconstitution using autologous peripheral blood stem cell (PBSC) than using autologous bone marrow stem cells. A large number of PBSC can be collected by leukapheresis during the hematological recovery after induction or salvage chemotherapy. In our experience we demonstrated that several separators, even if they have different results in mononuclear cell (MNC) yields, red blood cell and platelet contaminations, are able to collect PBSC for autotransplantation in patients with several malignant diseases and different status of disease. Eighty three patients were submitted to 590 leukapheresis procedures using 4 different blood cell separators: the results showed that all employed protocols are efficient in the collection of peripheral MNC even if after the widespread use of granulocytecolony stimulating factor (G-CSF) in the harvesting phase, the blood cell separator efficiency in terms of MNC is reduced. The use of GCSF in combination with other growth factors, during chemotherapy mobilization could simplify, in the future, this therapeutical program even if improvements in the efficiency of PBSC collection protocols are required.

Treatment of Multiple Myeloma with Autologous Blood Stem Cell Transplantation. Preliminary Results of an Italian Multicentric Pilot Study

Starting from May, 1991, 35 untreated myeloma patients entered a multicentric pilot study to evaluate the feasibility of a program of PBSC transplantation for previously untreated myeloma patients. The schedule was as follows: 2 cycles of VAD followed by CY, 7 g/mq + G-CSF (Granulokine, Roche) for 14 days, to increase and collect PBSC. The subsequent conditioning regimen was Melphalan + Busulfan followed by G-CSF. As maintenance R alpha-2 IFN was given, until relapse. The median follow-up is 14 months (4-22). On April 1993, 34 patients received at least 2 cycles of VAD, 27 were submitted to PBSC collection, 22 received conditioning regimen plus PBSC and 16 of them are in the maintenance treatment with IFN. Considering 28 patients for an intention to treat evaluation (35 -7 in treatment), responding patients are 71% with 46% who achieved CR. White cells and platelets raised to > 1000/mmc and >50,000/mmc after a median period of 10 and 13 days, from CY, and 11 and 14 days from transplant, respectively. Two patients relapsed, 2 others died while in PR because of CMV epatitis and candida pneumonia. The median number of CD34+ cells and CFU-GM was 24.75 x 106/kg b.w. and 28.1 x 104/kg b.w. respectively. In conclusion this treatment seems to be feasible and with low toxicity, but a longer follow-up is needed to evaluate the progression free survival of the high proportion of responding patients that we observed.

A new blood donation strategy: Automated blood collection (ABC)

Background

The aim of this study was to find out if Cobe Trima, a blood cell separator that automatically collects RBC, PLT and plasma, is adequate for routine multiple blood donation by apheresis.

Materials and Methods

Eighty donors underwent multiple blood component donations by Cobe Trima. Blood counts were determined on the apheresis products to analyze their quality.

Results

Eighty procedures were performed collecting 193 products. The average platelet yield was 3.5×1011 (± 0.46) in the 54 single product (SP) procedures and 7×1011 (± 0.88) in the 26 double product (DP) procedures. WBC contamination of the PLT products was 1.7 × 105 (1.2–4.2). The mean platelet efficiency was 60 ± 8.35% for SP and 66 ± 9.59% for DP. The hemoglobin (Hb) content per unit was 46.21 g (± 7.84) in 8 DP and 40.82 g (± 6.41) in 34 SP procedures.

Conclusion

The production of standardized blood components with good PLT yield and low WBC contamination plus high efficiency makes Trima one of the best blood cell separators of the new generation.

Large Volume Leukapheresis for Collecting Hemopoietic Progenitors: Role of CD 34+ Precount in Predicting Successful Collection

In this work we evaluated the efficacy of stem cell collection with Large Volume Procedures. (LVP), and analysed the importance of the CD34+ cell precount in promoting the collection of a sufficient number of CD34+ cells for transplantation, using the Univariate Logistic Regression analysis. Eighty-nine leukapheresis were performed in 49 patients with hematological malignancies and solid tumors, mobilized with chemotherapy plus Granulocyte Colony Stimulating Factor (G-CSF). For each procedure 15.8 liters of blood were processed. The median value of Nucleated Cells (NC) and CD34+ cells precount was respectively 8.29 × 109/ml (range 1.13÷45.4) and 43.08 × 103/ml (range 1.06÷795.2). Results show the capability of LVP to collect large quantities of hemopoietic progenitors with a median CD34+ cell total yield of 215.02 × 106 (range 5.03÷2210). The yields per patients’ body weight were: CD34+ cells 3.23 × 106/kg (range 0.081÷41.58). The regression analysis between blood cell precounts and collection yields gave the following correlations: the CD34+ cell precount correlates with CD34+ yield (r = 0.78 p < 0.00) and with CD34+ cell yield/kg (r = 0.76 p < 0.00). The number of CD34+ cells processed correlated with the number of CD34+ cells collected/kg (r = 0.83 p < 0.000). To investigate the importance of CD 34+ cell precount in promoting CD34+ cell yields ≥2.5 × 106/kg we performed a Univariate Logistic Regression analysis that showed in our patients a probability of collecting ≥2.5 × 106 CD34+/kg that rose from 0.6 to 0.95 for CD 34+ precounts that oscillated from 30 to 40 × 103 CD34+ cells/ml, respectively. The Univariate Logistic Regression gave a probability of collecting ≥2.5 × 106 CD34+ cells/kg that oscillated between 0.64÷0.98 for values of CD34+ cells processed from 6 × 106/kg to 8 × 106/kg, p <0.000. Sixty-three percent of patients reached the target dose of 2.5 × 106 CD34+ cells/kg with only one LVP. Until now 12 patients have been transplanted and all have had a prompt and complete lasting recovery. These results confirm the efficacy of LVP in harvesting hemopoietic progenitors and their ability in reconstituting hemopoiesis of transplanted patients, enabling the estimation of CD34+ precounts and CD34+ cells processed values, highly predictive for the collection of ≥2.5 × 106 CD34+ cells/kg. Furthermore, the Logistic Model suggests that the best strategy to plan a successful CD34+ cell collection procedure is to identify for each patient the amount of CD34+ cells/kg to be processed rather than the fixed processing of 3÷5 blood volumes in all patients.

The Application of Two Different Blood Cell Separators to Harvest CD34+ Cells in Patients Suffering from Non Hodgkin's Lymphoma

From January 1996 until now, thirty-eight PBSC procedures were carried out on 20 patients suffering from NHL, mobilized by polichemotherapy regimens plus recombinant human Granulocyte-Growth Factor (rhG-CSF). Patients were enrolled in PBSC procedures using Dideco Excel (group A) and Cobe Spectra v.4.7 (group B) blood cell separators. Twelve patients were enrolled in group A (6 males and 6 females, median age 33) and 9 patients in group B (5 males and 4 females, median age 55). The mean White Blood Cell (WBC) and Mononuclear Cells Fraction (MNC) peripheral blood counts were not statistically different in either group and neither were blood CD34+ cell peripheral counts. CD34+ cell peripheral value was predictive of the CD34+ yield while mean values of harvested CD34+ cells were not significantly different. CD34+ cell efficiences were statistically the same. The CD34+ cell purity of the apheresis harvest was statistically different between the two groups (group A = 3.0 ± 2.2%; group B = 1 ± 0.9%) p = 0.001. High CD34+ cell yields were observed in both groups which confirms that both blood cell separators are able to harvest hematopoietic progenitor cells from peripheral blood.

Unravelling the Effects of the Mutation m.3571insC/MT-ND1 on Respiratory Complexes Structural Organization

Mammalian respiratory complex I (CI) biogenesis requires both nuclear and mitochondria-encoded proteins and is mostly organized in respiratory supercomplexes. Among the CI proteins encoded by the mitochondrial DNA, NADH-ubiquinone oxidoreductase chain 1 (ND1) is a core subunit, evolutionary conserved from bacteria to mammals. Recently, ND1 has been recognized as a pivotal subunit in maintaining the structural and functional interaction among the hydrophilic and hydrophobic CI arms. A critical role of human ND1 both in CI biogenesis and in the dynamic organization of supercomplexes has been depicted, although the proof of concept is still missing and the critical amount of ND1 protein necessary for a proper assembly of both CI and supercomplexes is not defined. By exploiting a unique model in which human ND1 is allotopically re-expressed in cells lacking the endogenous protein, we demonstrated that the lack of this protein induces a stall in the multi-step process of CI biogenesis, as well as the alteration of supramolecular organization of respiratory complexes. We also defined a mutation threshold for the m.3571insC truncative mutation in mitochondrially encoded NADH:ubiquinone oxidoreductase core subunit 1 (MT-ND1), below which CI and its supramolecular organization is recovered, strengthening the notion that a certain amount of human ND1 is required for CI and supercomplexes biogenesis.

Feasibility of allogeneic stem-cell transplantation after azacitidine bridge in higher-risk myelodysplastic syndromes and low blast count acute myeloid leukemia: results of the BMT-AZA prospective study

Background

Allogeneic stem-cell transplantation (HSCT) is the only curative treatment in myelodysplastic syndromes (MDS). Azacitidine (AZA) is increasingly used prior to HSCT, however in Europe it is only approved for patients who are not eligible for HSCT.

Patients and methods

We conducted a phase II multicenter study to prospectively evaluate the feasibility of HSCT after treatment with AZA in 70 patients with a myelodysplastic syndrome (MDS), 19 with acute myeloid leukemia (AML), and 8 with chronic myelomonocytic leukemia (CMML). After a median of four cycles (range 1-11): 24% of patients achieved complete remission, 14% partial remission, 8% hematologic improvement, 32% had stable and 22% progressive disease. Ten patients discontinued treatment before the planned four cycles, due to an adverse event in nine cases.

Results

A HSC donor was identified in 73 patients, and HSCT was performed in 54 patients (74% of patients with a donor). Main reasons for turning down HSCT were lack of a donor, an adverse event, or progressive disease (9, 12, and 16 patients, respectively). At a median follow-up of 20.5 months from enrolment, response to AZA was the only independent prognostic factor for survival. Compared to baseline assessment, AZA treatment did not affect patients' comorbidities at HSCT: the HCT-CI remained stable in 62% patients, and worsened or improved in 23% and 15% of patients, respectively.

Conclusions

Our study shows that HSCT is feasible in the majority of patients with HR-MDS/AML/CMML-2 after AZA treatment. As matched unrelated donor was the most frequent source of donor cells, the time between diagnosis and HSCT needed for donor search could be 'bridged' using azacitidine. These data show that AZA prior to HSCT could be a better option than intensive chemotherapy in higher-risk MDS. The trial has been registered with the EudraCT number 2010-019673-1.

Platinum-induced mitochondrial DNA mutations confer lower sensitivity to paclitaxel by impairing tubulin cytoskeletal organization

Development of chemoresistance is a cogent clinical issue in oncology, whereby combination of anticancer drugs is usually preferred also to enhance efficacy. Paclitaxel (PTX), combined with carboplatin, represents the standard first-line chemotherapy for different types of cancers. We here depict a double-edge role of mitochondrial DNA (mtDNA) mutations induced in cancer cells after treatment with platinum. MtDNA mutations were positively selected by PTX, and they determined a decrease in the mitochondrial respiratory function, as well as in proliferative and tumorigenic potential, in terms of migratory and invasive capacity. Moreover, cells bearing mtDNA mutations lacked filamentous tubulin, the main target of PTX, and failed to reorient the Golgi body upon appropriate stimuli. We also show that the bioenergetic and cytoskeletal phenotype were transferred along with mtDNA mutations in transmitochondrial hybrids, and that this also conferred PTX resistance to recipient cells. Overall, our data show that platinum-induced deleterious mtDNA mutations confer resistance to PTX, and confirm what we previously reported in an ovarian cancer patient treated with carboplatin and PTX who developed a quiescent yet resistant tumor mass harboring mtDNA mutations.

Mild phenotypes and proper supercomplex assembly in human cells carrying the homoplasmic m.15557G > A mutation in cytochrome b gene

Respiratory complex III (CIII) is the first enzymatic bottleneck of the mitochondrial respiratory chain both in its native dimeric form and in supercomplexes. The mammalian CIII comprises 11 subunits among which cytochrome b is central in the catalytic core, where oxidation of ubiquinol occurs at the Qo site. The Qo- or PEWY-motif of cytochrome b is the most conserved through species. Importantly, the highly conserved glutamate at position 271 (Glu271) has never been studied in higher eukaryotes so far and its role in the Q-cycle remains debated. Here, we showed that the homoplasmic m.15557G > A/MT-CYB, which causes the p.Glu271Lys amino acid substitution predicted to dramatically affect CIII, induces a mild mitochondrial dysfunction in human transmitochondrial cybrids. Indeed, we found that the severity of such mutation is mitigated by the proper assembly of CIII into supercomplexes, which may favor an optimal substrate channeling and buffer superoxide production in vitro.

Imaging of post-surgical treatment and of related complications in spinal trauma

Spinal trauma is a devastating event with a high morbidity and mortality. The rationale of imaging is to diagnose the traumatic abnormalities and characterize the type of injury, to estimate the severity of the lesions, to evaluate the potential spinal instability. In case of spinal instability, the goals of operative treatment are decompression of the spinal cord canal and stabilization of the disrupted vertebral column. Particularly, diagnostic imaging, mainly by CT and MR, has a main role in the post-treatment evaluation. The neuroradiological evaluation of the postoperative spine requires a general knowledge of the surgical approach to each spinal region and of the normal temporal evolution of expected postoperative changes. The neuroradiologist should evaluate the devices implanted, their related complications and promptly alert the surgeon of acute complications, mainly vascular and infective. During the follow-up, it is mandatory to know and search chronic complications as pseudomeningocele, accelerated degenerative disease, arachnoiditis, peridural fibrosis. Knowledge of specific complications relating to each surgical approach will assist the neuroradiologist in interpretation of postoperative images.

The α-ketoglutarate dehydrogenase complex in cancer metabolic plasticity

Deregulated metabolism is a well-established hallmark of cancer. At the hub of various metabolic pathways deeply integrated within mitochondrial functions, the α-ketoglutarate dehydrogenase complex represents a major modulator of electron transport chain activity and tricarboxylic acid cycle (TCA) flux, and is a pivotal enzyme in the metabolic reprogramming following a cancer cell’s change in bioenergetic requirements. By contributing to the control of α-ketoglutarate levels, dynamics, and oxidation state, the α-ketoglutarate dehydrogenase is also essential in modulating the epigenetic landscape of cancer cells. In this review, we will discuss the manifold roles that this TCA enzyme and its substrate play in cancer.

Stromal PTEN inhibits the expansion of mammary epithelial stem cells through Jagged-1

Fibroblasts within the mammary tumor microenvironment are active participants in carcinogenesis mediating both tumor initiation and progression. Our group has previously demonstrated that genetic loss of PTEN in mammary fibroblasts induces an oncogenic secretome that remodels the extracellular milieu accelerating ErbB2-driven mammary tumor progression. While these prior studies highlighted a tumor suppressive role for stromal PTEN, how the adjacent normal epithelium transforms in response to PTEN loss was not previously addressed. To identify these early events, we have evaluated both phenotypic and genetic changes within the pre-neoplastic mammary epithelium of mice with and without stromal PTEN expression. We report that fibroblast-specific PTEN deletion greatly restricts mammary ductal elongation and induces aberrant alveolar side-branching. These mice concomitantly exhibit an expansion of the mammary epithelial stem cell (MaSC) enriched basal/myoepithelial population and an increase in in vitro stem cell activity. Further analysis revealed that NOTCH signaling, specifically through NOTCH3, is diminished in these cells. Mechanistically, JAGGED-1, a transmembrane ligand for the NOTCH receptor, is downregulated in the PTEN-null fibroblasts leading to a loss in the paracrine activation of NOTCH signaling from the surrounding stroma. Reintroduction of JAGGED-1 expression within the PTEN-null fibroblasts was sufficient to abrogate the observed increase in colony forming activity implying a direct role for stromal JAGGED-1 in regulation of mammary stem cell properties. Importantly, breast cancer patients whose tumors express both low stromal JAG1 and low stromal PTEN exhibit a shorter time to recurrence than those whose tumors express low levels of either alone suggesting similar stromal signaling in advanced disease. Combined, these results unveil a novel stromal PTEN-to-JAGGED-1 axis in maintaining the mammary epithelial stem cell niche, and subsequently inhibiting breast cancer initiation and disease progression.