Genotype-phenotype correlations and nephroprotective effects of RAAS inhibition in patients with autosomal recessive Alport syndrome.

BACKGROUND: Autosomal recessive Alport syndrome (ARAS) is caused by pathogenic variants in both alleles of either COL4A3 or COL4A4 genes. Reports on ARAS are rare due to small patient numbers and there are no reports on renin-angiotensin-aldosterone system (RAAS) inhibition therapy in ARAS. METHODS: Retrospective study in 101 patients with ARAS from Chinese Registry Database of Hereditary Kidney Diseases and European Alport Registry. Genotype-phenotype correlations and nephroprotective effects of RAAS inhibition in ARAS were evaluated. RESULTS: Median age was 15 years (range 1.5-46 years). Twelve patients progressed to stage 5 chronic kidney disease (CKD5) at median age 20.5 years. Patients without missense variants had both higher prevalence and earlier onset age of hearing loss, nephrotic-range proteinuria, more rapid decline of eGFR, and earlier onset age of CKD5 compared to patients with 1 or 2 missense variants. Most patients (79/101, 78%) currently are treated with RAAS inhibitors; median age at therapy initiation was 10 years and mean duration 6.5 ± 6.0 years. Median age at CKD5 for untreated patients was 24 years. RAAS inhibition therapy delayed CKD5 onset in those with impaired kidney function (T-III) to median age 35 years, but is undefined in treated patients with proteinuria (T-II) due to low number of events. No treated patients with microalbuminuria (T-I) progressed to CKD5. ARAS patients with 1 or 2 missense variants showed better response to treatment than patients with non-missense-variants. CONCLUSIONS: Our study provides the first evidence for early use of RAAS inhibition therapy in patients with ARAS. Furthermore, genotype in ARAS correlates with response to therapy in favor of missense variants.

Management of chronic hand and foot eczema. An Australia/New Zealand Clinical narrative.

Chronic hand/foot eczemas are common, but treatment is often challenging, with widespread dissatisfaction over current available options. Detailed history is important, particularly with regard to potential exposure to irritants and allergens. Patch testing should be regarded as a standard investigation. Individual treatment outcomes and targets, including systemic therapy, should be discussed early with patients, restoring function being the primary goal, with clearing the skin a secondary outcome. Each new treatment, where appropriate, should be considered additive or overlapping to any previous therapy. Management extends beyond mere pharmacological or physical treatment, and requires an encompassing approach including removal or avoidance of causative factors, behavioural changes and social support. To date, there is little evidence to guide sequences or combinations of therapies. Moderately symptomatic patients (e.g. DLQI ≥ 10) should be started on a potent/super-potent topical corticosteroid applied once or twice per day for 4 weeks, with tapering to twice weekly application. If response is inadequate, consider phototherapy, and then a 12-week trial of a retinoid (alitretinoin or acitretin). Second line systemic treatments include methotrexate, ciclosporin and azathioprine. For patients presenting with severe symptomatic disease (DLQI ≥ 15), consider predniso(lo)ne 0.5-1.0 mg/kg/day (or ciclosporin 3 - 5 mg/kg/day) for 4-6 weeks with tapering, and then treating as for moderate disease as above. In non-responders, botulinum toxin and/or iontophoresis, if associated with hyperhidrosis, may sometimes help. Some patients only respond to long-term systemic corticosteroids. The data on sequencing of newer agents, such as dupilumab or JAK inhibitors, are immature.

Prevalence, incidence and management of atopic dermatitis in Australian general practice using routinely collected data from MedicineInsight.

BACKGROUND/OBJECTIVES: The prevalence of atopic dermatitis (AD) has increased significantly in industrialised countries in recent decades but data about the incidence or prevalence of AD in Australia are sparse. We aimed to determine the prevalence and incidence of AD among patients seen in Australian general practice and the use of specified medicines. METHODS: This was a cross-sectional study of 2.1 million patients attending 494 general practices in the MedicineInsight program from 1 January 2017 to 31 December 2018. We assessed the prevalence (lifetime and current), incidence, management and severity of AD. RESULTS: The lifetime (ever diagnosed) prevalence of AD in this general practice population was 16.4% and was greater in females (17.3%) than males (15.3%). One in five patients with AD were classified as having moderate-to-severe disease. Prevalence over the last two years was 6.3%. The incidence of AD in 2018 was 2.0% and was greater in females (2.2%) and for patients aged 0-4 years (3.9%). Patients with AD had an increased risk of insomnia, anxiety and depression, compared to those with no recorded AD. For AD patients, topical corticosteroids were the most commonly prescribed AD medication (36.5%) and topical calcineurin inhibitors the least (0.1%), with systemic corticosteroids (15.6%) more commonly prescribed than other immunosuppressants (0.9%). CONCLUSIONS: Our findings provide important insights into the epidemiology of AD and its management in Australian general practice. This information is likely to be useful in planning effective interventions to support GPs in the optimal management of patients with AD.

Managing atopic dermatitis with systemic therapies in adults and adolescents: An Australian/New Zealand narrative.

With the rapid development of new, targeted therapies for the treatment of moderate/severe atopic dermatitis, it is opportune to review the available conventional systemic agents. We assess the published evidence for systemic therapies for atopic dermatitis and amalgamate this with real-world experience. Discussions are centred on when systemic therapy should be considered, which drug(s), what dose, how to sequence or combine these therapies, how long they should be continued for and what is considered success.

Atopic dermatitis in adults: An Australian management consensus.

BACKGROUND/OBJECTIVES: Atopic dermatitis (AD) has significant negative impact on health-related quality of life, mood, sleep, work productivity and everyday activities. Research into the use of new drugs in the management of AD continues to develop, and international updates and recommendations have been published. However, questions remain in the Australian setting. This consensus aims to provide evidence-based insights and practical advice on the management of adult AD in Australia. METHODS: A panel (five dermatologists and one clinical immunologist) met to review the literature, critically examine clinical questions of relevance to Australian healthcare practitioners and develop a series of recommendation statements. A consensus panel, comprising the initial panel plus nine additional members, used a 2-round Delphi voting process to determine a set of final guidance statements. CONSENSUS: ≥75% agreement in the range 7-9. RESULTS: Round 1 voting comprised 66 guidance statements. Of these, consensus was reached on 26, which were retained, and five were removed. The remainder (35) were modified and one new guidance statement was added for inclusion in round 2 voting. After round 2, consensus was reached on 35, which were retained, and one was removed (considered redundant). The 61 guidance statements upon which consensus was reached were then used to support a series of core consensus recommendations and a management flow chart. CONCLUSIONS: Expert consensus recommendations providing practical guidance of clinical relevance to specialists and primary care physicians in Australia have been developed. Dissemination of this guidance and evaluation of its impact on patient outcomes remain to be undertaken.

Psoriasis and cancer. An Australian/New Zealand narrative.

Patients with psoriasis have an increased risk of cancer, which may be due to impaired immune surveillance, immune modulatory treatments, chronic inflammation and/or co-risk factors such as obesity. The increase in treatment-independent solid cancers, including urinary/bladder cancers, oropharynx/larynx, liver/gallbladder and colon/rectal cancers, seem to be linked to alcohol and smoking. Lung cancer and nonmelanoma skin cancer are also increased in patients with psoriasis. The risk of nonmelanoma skin cancer increases with age and severity of psoriasis. It is also higher in men, particularly for squamous cell carcinoma, which may reflect previous exposure to PUVA and/or ciclosporin. The risk of cutaneous T-cell lymphoma is substantially higher in patients with moderate-to-severe psoriasis. Biologic therapies are independently associated with a slight increase risk of cancer, but this is less than ciclosporin, with the risk confounded by disease severity and other co-risk factors. The risk of cancer from low-dose methotrexate is likely minimal. In contrast, acitretin is likely protective against a variety of solid and haematological malignancies. The data on small molecule therapies such as apremilast are too immature for comment, although no signal has yet been identified. The decision whether to stop psoriasis immune modulatory treatments following a diagnosis of cancer, and when to resume, needs to be considered in the context of the patients' specific cancer. However, there is no absolute need to stop any treatment other than possibly ciclosporin, unless there is a concern over an increased risk of serious infection or drug-drug interaction with cancer-directed therapies, including radiotherapy.

Psoriasis and infection. A clinical practice narrative.

The Australasian Psoriasis Collaboration has developed a clinical practice narrative with respect to the relationship between psoriasis, its treatment and infection. The cutaneous microbiome of patients with psoriasis is different to those without psoriasis, although the significance of this is unclear. Whilst a wide range of microorganisms has been associated with psoriasis (including ß-haemolytic streptococci, Staphylococcus aureus, Porphyromonas gingivalis, Candida albicans, Chlamydia psittaci, human immunodeficiency virus and hepatitis C virus), there is limited evidence that antimicrobial therapy is of direct benefit in preventing flares of psoriasis. Psoriasis is independently associated with an increased risk of serious infection, but the absolute risk is low. The risk of serious infections is further increased with immune-modulatory treatments. The decision whether to, and when to, stop or resume immune-modulatory treatment after a serious infection has occurred depends on risk assessment for that patient, taking into account the infection being treated, the risk of recurrent infection, any interventions that can modify the risk and the need for psoriasis control. Live vaccines (e.g. MMR, varicella, zoster and yellow fever) are generally contraindicated in patients with psoriasis on immune-modulatory agents, but this depends on the degree of immune suppression and individual risk factors. Wound healing in psoriasis is normal. Treatment with infliximab, adalimumab, etanercept, methotrexate and ciclosporin can safely be continued through low-risk surgical procedures. For moderate- and high-risk surgeries, a case-by-case approach should be taken based on the patient's individual risk factors and comorbidities.

Long-term management of moderate-to-severe atopic dermatitis with dupilumab and concomitant topical corticosteroids (LIBERTY AD CHRONOS): a 1-year, randomised, double-blinded, placebo-controlled, phase 3 trial.

BACKGROUND: Dupilumab (an anti-interleukin-4-receptor-α monoclonal antibody) blocks signalling of interleukin 4 and interleukin 13, type 2/Th2 cytokines implicated in numerous allergic diseases ranging from asthma to atopic dermatitis. Previous 16-week monotherapy studies showed that dupilumab substantially improved signs and symptoms of moderate-to-severe atopic dermatitis with acceptable safety, validating the crucial role of interleukin 4 and interleukin 13 in atopic dermatitis pathogenesis. We aimed to evaluate the long-term efficacy and safety of dupilumab with medium-potency topical corticosteroids versus placebo with topical corticosteroids in adults with moderate-to-severe atopic dermatitis. METHODS: In this 1-year, randomised, double-blinded, placebo-controlled, phase 3 study (LIBERTY AD CHRONOS), adults with moderate-to-severe atopic dermatitis and inadequate response to topical corticosteroids were enrolled at 161 hospitals, clinics, and academic institutions in 14 countries in Europe, Asia-Pacific, and North America. Patients were randomly assigned (3:1:3) to subcutaneous dupilumab 300 mg once weekly (qw), dupilumab 300 mg every 2 weeks (q2w), or placebo via a central interactive voice/web response system, stratified by severity and global region. All three groups were given concomitant topical corticosteroids with or without topical calcineurin inhibitors where inadvisable for topical corticosteroids. Topical corticosteroids could be tapered, stopped, or restarted on the basis of disease activity. Coprimary endpoints were patients (%) achieving Investigator's Global Assessment (IGA) 0/1 and 2-point or higher improvement from baseline, and Eczema Area and Severity Index 75% improvement from baseline (EASI-75) at week 16. Week 16 efficacy and week 52 safety analyses included all randomised patients; week 52 efficacy included patients who completed treatment by US regulatory submission cutoff. This study is registered with ClinicalTrials.gov, NCT02260986. FINDINGS: Between Oct 3, 2014, and July 31, 2015, 740 patients were enrolled: 319 were randomly assigned to dupilumab qw plus topical corticosteroids, 106 to dupilumab q2w plus topical corticosteroids, and 315 to placebo plus topical corticosteroids. 623 (270, 89, and 264, respectively) were evaluable for week 52 efficacy. At week 16, more patients who received dupilumab plus topical corticosteroids achieved the coprimary endpoints of IGA 0/1 (39% [125 patients] who received dupilumab plus topical corticosteroids qw and 39% [41 patients] who received dupilumab q2w plus topical corticosteroids vs 12% [39 patients] who received placebo plus topical corticosteroids; p<0·0001) and EASI-75 (64% [204] and 69% [73] vs 23% [73]; p<0·0001). Week 52 results were similar. Adverse events were reported in 261 (83%) patients who received dupilumab qw plus topical corticosteroids, 97 (88%) patients who received dupilumab q2w, and 266 (84%) patients who received placebo, and serious adverse events in nine (3%), four (4%), and 16 (5%) patients, respectively. No significant dupilumab-induced laboratory abnormalities were noted. Injection-site reactions and conjunctivitis were more common in patients treated with dupilumab plus topical corticosteroids-treated patients than in patients treated with placebo plus topical corticosteroids. INTERPRETATION: Dupilumab added to standard topical corticosteroid treatment for 1 year improved atopic dermatitis signs and symptoms, with acceptable safety. FUNDING: Sanofi and Regeneron Pharmaceuticals Inc.

The Australasian Psoriasis Collaboration view on methotrexate for psoriasis in the Australasian setting.

The Australasian Psoriasis Collaboration reviewed methotrexate (MTX) in the management of psoriasis in the Australian and New Zealand setting. The following comments are based on expert opinion and a literature review. Low-dose MTX (< 0.4 mg/kg per week) has a slow onset of action and has moderate to good efficacy, together with an acceptable safety profile. The mechanism of action is anti-inflammatory, rather than immunosuppressive. For pretreatment, consider testing full blood count (FBC), liver and renal function, non-fasting lipids, hepatitis serology, HbA1c and glucose. Body mass index and abdominal circumference should also be measured. Optional investigations in at-risk groups include an HIV test, a QuantiFERON-TB Gold test and a chest X-ray. In patients without complications, repeat the FBC at 2-4 weeks, then every 3-6 months and the liver/renal function test at 3 months and then every 6 months. There is little evidence that a MTX test dose is of value. Low-dose MTX rarely causes clinically significant hepatotoxicity in psoriasis. Most treatment-emergent liver toxicity is related to underlying metabolic syndrome and non-alcoholic fatty liver disease or non-alcoholic steatohepatitis. Alcohol itself is not contraindicated, but should be limited to < 20 gm/day. [Correction added on 6 January 2017, after first online publication: '20 mg/day' has been corrected to '20 gm/day'.] Although MTX is a potential teratogen post-conception, there is little evidence for this pre-conception. MTX does not affect the quality of sperm. There is no evidence that MTX reduces healing, so there is no specific need to stop MTX peri-surgery. MTX may be used in combination with cyclosporine, acitretin, prednisone and anti-tumour necrosis factor biologics.

Consensus recommendations on the use of daylight photodynamic therapy with methyl aminolevulinate cream for actinic keratoses in Australia.

Australia has the highest prevalence of actinic keratoses (AK) worldwide. Because of the risk of transformation of AK to invasive squamous cell carcinomas, consensus guidelines recommend that AK are removed using appropriate therapies to prevent progression to invasive disease. Daylight photodynamic therapy (PDT) is emerging as an efficacious treatment for AK, particularly for patients who require treatment of large areas of chronic actinic damage that can be exposed easily to daylight. Daylight PDT with methyl aminolevulinate (MAL) cream is a simple treatment for AK, almost painless, well tolerated and convenient, requiring minimal time in the clinic. Randomised controlled studies from northern Europe and Australia support the use of daylight PDT as an effective therapy for grade I and II AK on the face and scalp. There is sufficient daylight to conduct daylight PDT in Australia at any time of the year and during most weather conditions. Hence, daylight PDT with MAL can be included as an effective and well-tolerated new treatment option for the treatment of AK in Australia. These consensus recommendations provide guidelines for Australian clinicians on the use of daylight PDT in the treatment of diagnosed AK.

Treatment of face and scalp solar (actinic) keratosis with daylight-mediated photodynamic therapy is possible throughout the year in Australia: Evidence from a clinical and meteorological study.

BACKGROUND/OBJECTIVES: Solar (actinic) keratosis (AK) is an emergent concern worldwide and is associated with an increased risk of development of non-melanoma skin cancer, especially squamous cell carcinoma. Daylight-mediated photodynamic therapy (DL-PDT) using methyl aminolaevulinate cream has proved to be an effective, nearly painless, and more convenient alternative to conventional PDT for the treatment of AK. In a phase III, randomised, controlled trial performed in Australia, the mean irradiance (light intensity) received by patients during DL-PDT treatment, assessed via a spectroradiometer, was 305 W/m(2) (min. 40 to max. 585 W/m(2) ) with similar efficacy irrespective of intensity or dose. The objective of the present meteorological study was to assess the suitability of natural daylight to perform DL-PDT for the treatment of face and scalp AK during different periods of the year and different geographical locations and latitudes across Australia. METHODS: To determine daylight irradiance during a complete year in eight different geographical locations throughout Australia, we used meteorological software (Meteonorm, Meteotest, Bern, Switzerland), and available solar radiation and weather data from 1986-2005. RESULTS: The average daily irradiance remained within the levels (40-585 W/m(2) ) measured during the clinical DL-PDT study in Australia, throughout the year and in all geographical locations investigated (yearly average from Darwin 548 W/m(2) to Hobart 366 W/m(2) ). CONCLUSIONS: DL-PDT for the treatment of face and scalp AK in Australia can be performed effectively throughout the entire year as long as weather conditions permit daylight exposure and allow participants to remain under direct light for 2 h.

Preclinical Alterations in the Serum of COL(IV)A3(-)/(-) Mice as Early Biomarkers of Alport Syndrome.

The efficiency of the inhibition of the angiotensin converting enzyme, the most widely used therapy for the Alport syndrome, depends on the onset of the therapy-the earlier the better. Hence, early progressive biomarkers are urgently required to allow for preclinical diagnosis, an early start of possible therapy as well as the monitoring of this therapy. In the present study, an improved comprehensive and precise proteomic approach has been applied to the serum of juvenile Alport-mice, nontreated and treated, and wild-type controls of various ages to search for biomarkers. With a total of 2542 stringently altered proteins, the serum composition clearly shows a dependency on age, that is, stage, and therapy. Initially, the serum constituents indicate an enhanced extracellular matrix remodeling, cell damage, and the production of particular acute phase proteins. A panel of 15 potential biomarker candidates has been identified. In later stages, renal filtration failure and systemic acute phase reaction determine the composition of the serum; an effect that is well-known for manifested human Alport syndrome. With a small number of mouse urine samples, for example, the proteomic results for gelsolin could be verified using ELISA. Once verified in man, these early biomarkers would allow for a sensitive and specific diagnosis of the Alport syndrome in children as well as facilitate the monitoring of a possible therapy.

Secretion of ERP57 is important for extracellular matrix accumulation and progression of renal fibrosis, and is an early sign of disease onset.

Renal fibrosis is characterized by excessive accumulation of extracellular matrix (ECM), which compromises organ function by replacing normal organ tissue. The molecular mechanisms leading to renal fibrosis are not fully understood. Here we demonstrated that TGFß1, AGT or PDGF stimulation of renal cells resulted in endoplasmic reticulum (ER) stress followed by activation of the protective unfolded protein response pathway and a high secretory level of protein disulfide isomerase ERP57 (also known as PDIA3). The TGFß1-induced impairment of ER function could be reversed by treatment with BMP7, suggesting a specific involvement in renal fibrosis. A clear correlation between the degree of fibrosis, ER stress and the level of ERP57 could be seen in fibrosis animal models and in biopsies of renal fibrosis patients. Protein interaction studies revealed that secreted ERP57 exhibits a strong interaction with ECM proteins. Knockdown of ERP57 or antibody-targeted inhibition of the secreted form significantly impaired the secretion and accumulation of ECM. Moreover, ERP57 was excreted in the early stages of chronic kidney disease, and its level in urine correlated with the degree of renal fibrosis, suggesting that the secretion of ERP57 represents one of the first signs of renal fibrosis onset and progression.

Discoidin domain receptor 1 protein is a novel modulator of megakaryocyte-collagen interactions.

Growing evidence demonstrates that extracellular matrices regulate many aspects of megakaryocyte (MK) development; however, among the different extracellular matrix receptors, integrin α2ß1 and glycoprotein VI are the only collagen receptors studied in platelets and MKs. In this study, we demonstrate the expression of the novel collagen receptor discoidin domain receptor 1 (DDR1) by human MKs at both mRNA and protein levels and provide evidence of DDR1 involvement in the regulation of MK motility on type I collagen through a mechanism based on the activity of SHP1 phosphatase and spleen tyrosine kinase (Syk). Specifically, we demonstrated that inhibition of DDR1 binding to type I collagen, preserving the engagement of the other collagen receptors, glycoprotein VI, α2ß1, and LAIR-1, determines a decrease in MK migration due to the reduction in SHP1 phosphatase activity and consequent increase in the phosphorylation level of its main substrate Syk. Consistently, inhibition of Syk activity restored MK migration on type I collagen. In conclusion, we report the expression and function of a novel collagen receptor on human MKs, and we point out that an increasing level of complexity is necessary to better understand MK-collagen interactions in the bone marrow environment.

Effects of mycophenolate mofetil on kidney function and phosphorylation status of renal proteins in Alport COL4A3-deficient mice.

BACKGROUND: We investigated the effects of mycophenolate mofetil (MMF) on kidney function and on protein phosphorylation in a mouse model for the human Alport syndrome. METHODS: COL4A3-deficient (COL4A3-/-) mice were randomly allocated to receive a placebo (PLC COL4A3-/-) or MMF treatment (MMF COL4A3-/-). Wild type mice (WT) were used as controls. Changes in serum creatinine, total protein and blood urea nitrogen (BUN), concentrations of mycophenolic acid (MPA) and its glucuronide metabolite (MPAG), serum protein electrophoresis, urine dipstick chemistry and sediment were measured. Changes in the phosphorylation status of renal proteins and histology were analyzed. RESULTS: MMF influenced kidney function and protein phosphorylation. Serum creatinine and BUN were lower in MMF treated compared to PLC treated COL4A3-/- mice. Serum albumin and alpha-1 globulins were significantly decreased while serum creatinine, alpha-2 globulins, urine dipstick protein, leukocyte esterase, hemoglobin and red blood cells were all increased in both COL4A3-/- groups compared to WT. Differential 2DE-gel analysis identified six phosphorylated kidney protein spots that were significantly altered by MMF. CONCLUSIONS: These data suggest that the MMF treatment in this murine model moderately improved kidney function and reversed the phosphorylation status of six renal phosphoprotein spots to that seen in WT mice.

Antifibrotic, nephroprotective effects of paricalcitol versus calcitriol on top of ACE-inhibitor therapy in the COL4A3 knockout mouse model for progressive renal fibrosis.

BACKGROUND: The COL4A3-/- mouse serves as animal model for progressive renal fibrosis. Using this animal model, the present study investigates the nephroprotective effects of Paricalcitol versus Calcitriol alone and on top of ACE-inhibitor therapy. METHODS: Eighty six mice were divided into six groups: (PC) with Paricalcitol 0.1 mcg/kg, (CA) Calcitriol 0.03 mcg/kg (dose equipotent), (PLAC) vehicle 0.1 mL i.p. five times per week, (ACE + PC) Paricalcitol plus Ramipril, (ACE + CA) Calcitriol plus Ramipril and (ACE + PLAC) vehicle plus Ramipril 10 mg/kg/day p.o. ACE therapy started pre-emptively in Week 4, PC/CA therapy was initiated in 6-week-old animals with ongoing renal fibrosis and lasted for 8 weeks. Four to six animals were sacrificed after 9.5 weeks and kidneys were further investigated using histological, immunohistological and Western-blot techniques. Survival until end-stage renal failure was determined in the remaining animals. RESULTS: PC, but not CA, prolonged lifespan until renal failure by 13% compared with untreated controls (P = 0.069). ACE-inhibition prolonged lifespan by >50%. Added on top of ACE inhibition, ACE + PC (but not ACE + CA) even further prolonged lifespan by additional 18.0% (P < 0.01 versus ACE + PLAC) and improved renal function (blood urea nitrogen; P < 0.05 versus ACE + CA). Accumulation of extracellular matrix and renal scarring was decreased in PC and ACE + PC-treated mice. CONCLUSIONS: The present study demonstrated a substantial nephroprotective and antifibrotic effect of the vitamin D-receptor activator Paricalcitol on top of early ACE inhibition in the COL4A3-/- model of progressive kidney fibrosis. The synergistic effect of Paricalcitol on top of RAAS-blockade might as well be valuable in other chronic kidney diseases.

A luminal intermediate cell state maintains long-term prostate homeostasis and contributes to tumorigenesis.

Cellular heterogeneity poses tremendous challenges for developing cell-targeted therapies and biomarkers of clinically significant prostate cancer. The origins of this heterogeneity within normal adult and aging tissue remain unknown, leaving cellular states and transcriptional programs that allow expansions of malignant clones unidentified. To define cell states that contribute to early cancer development, we performed clonal analyses and single cell transcriptomics of normal prostate from genetically-engineered mouse models. We uncovered a luminal transcriptional state with a unique "basal-like" Wnt/p63 signaling ( luminal intermediate , LumI) which contributes to the maintenance of long-term prostate homeostasis. Moreover, LumI cells greatly expand during early stages of tumorigenesis in several mouse models of prostate cancer. Genetic ablation of p63 in vivo in luminal cells reduced the formation of aggressive clones in mouse prostate tumor models. Finally, the LumI cells and Wnt signaling appear to significantly increase in human aging prostate and prostate cancer samples, highlighting the importance of this hybrid cell state for human pathologies with potential translational impact.

Immune mechanisms shape the clonal landscape during early progression of prostate cancer.

Understanding the role of the immune microenvironment in modulating intratumor heterogeneity is essential for effective cancer therapies. Using multicolor lineage tracing in genetically engineered mouse models and single-cell transcriptomics, we show that slowly progressing tumors contain a multiclonal landscape of relatively homogeneous subpopulations within a well-organized tumor microenvironment. In more advanced and aggressive tumors, however, the multiclonal landscape develops into competing dominant and minor clones accompanied by a disordered microenvironment. We demonstrate that this dominant/minor landscape is associated with differential immunoediting, in which minor clones are marked by an increased expression of IFNγ-response genes and the T cell-activating chemokines Cxcl9 and Cxcl11. Furthermore, immunomodulation of the IFNγ pathway can rescue minor clones from elimination. Notably, the immune-specific gene signature of minor clones exhibits a prognostic value for biochemical recurrence-free survival in human prostate cancer. These findings suggest new immunotherapy approaches for modulating clonal fitness and tumor progression in prostate cancer.