The Journal of neuroscience : the official journal of the Society for Neuroscience
Saikia, JM;Chavez-Martinez, CL;Kim, ND;Allibhoy, S;Kim, HJ;Simonyan, L;Smadi, S;Tsai, KM;Romaus-Sanjurjo, D;Jin, Y;Zheng, B;
PMID: 35361703 | DOI: 10.1523/JNEUROSCI.2495-21.2022
The limited ability for axonal repair after spinal cord injury underlies long-term functional impairment. DLK (MAP3K12) is an evolutionarily conserved MAP3K implicated in neuronal injury signaling from C. elegans to mammals. However, whether DLK or its close homologue LZK (MAP3K13) regulates axonal repair in the mammalian spinal cord remains unknown. Here we assess the role of endogenous DLK and LZK in the regeneration and compensatory sprouting of corticospinal tract (CST) axons in mice of both sexes with genetic analyses in a regeneration competent background provided by PTEN deletion. We found that inducible neuronal deletion of both DLK and LZK, but not either kinase alone, abolishes PTEN deletion-induced regeneration and sprouting of CST axons, and reduces naturally-occurring axon sprouting after injury. Thus, DLK/LZK-mediated injury signaling operates not only in injured neurons to regulate regeneration, but also unexpectedly in uninjured neurons to regulate sprouting. Deleting DLK and LZK does not interfere with PTEN/mTOR signaling, indicating that injury signaling and regenerative competence are independently controlled. Together with our previous study implicating LZK in astrocytic reactivity and scar formation, these data illustrate the multicellular function of this pair of MAP3Ks in both neurons and glia in the injury response of the mammalian spinal cord.SIGNIFICANCE STATEMENT:Functional recovery after spinal cord injury is limited due to a lack of axonal repair in the mammalian central nervous system (CNS). DLK and LZK are two closely related protein kinases that have emerged as regulators of neuronal responses to injury. However, their role in axon repair in the mammalian spinal cord has not been described. Here we show that DLK and LZK together play critical roles in axonal repair in the mammalian spinal cord, validating them as potential targets to promote repair and recovery after spinal cord injury. In addition to regulating axonal regeneration from injured pathways, they also regulate compensatory axonal growth from uninjured pathways, indicating a more pervasive role in CNS repair than originally anticipated.
American Journal of Clinical Pathology
Baena-Del Valle JA, Zheng Q, Hicks JL, Trock HFBJ, Morrissey C, Corey E, Cornish TC, Sfanos KS, De Marzo AM.
PMID: - | DOI: 10.1093/ajcp/aqx094
Abstract
Objectives
Recent commercialization of methods for in situ hybridization using Z-pair probe/branched DNA amplification has led to increasing adoption of this technology for interrogating RNA expression in formalin-fixed, paraffin-embedded (FFPE) tissues. Current practice for FFPE block storage is to maintain them at room temperature, often for many years.
Methods
To examine the effects of block storage time on FFPE tissues using a number of RNA in situ probes with the Advanced Cellular Diagnostic’s RNAscope assay.
Results
We report marked reductions in signals after 5 years and significant reductions often after 1 year. Furthermore, storing unstained slides cut from recent cases (<1 year old) at –20°C can preserve hybridization signals significantly better than storing the blocks at room temperature and cutting the slides fresh when needed.
Conclusions
We submit that the standard practice of storing FFPE tissue blocks at room temperature should be reevaluated to better preserve RNA for in situ hybridization.
Loveridge C, Mui E, Patel R, Tan EH, Ahmad I, Welsh M, Galbraith J, Hedley A, Nixon C, Blyth K, Sansom OJ, Leung HY.
PMID: 28515147 | DOI: 10.1158/0008-5472.CAN-16-2565
Prostate cancer (PCa) does not appear to respond to immune checkpoint therapies where T cell infiltration may be a key limiting factor. Here we report evidence that ablating the growth regulatory kinase Erk5 can increase T cell infiltration in an established Pten-deficient mouse model of human PCa. Mice that were doubly mutant in prostate tissue for Pten and Erk5 (prostate DKO) exhibited a markedly increased median survival with reduced tumor size and proliferation compared to control Pten-mutant mice, the latter of which exhibited increased Erk5 mRNA expression. A comparative transcriptomic analysis revealed upregulation in prostate DKO mice of the chemokines Ccl5 and Cxcl10, two potent chemoattractants for T lymphocytes. Consistent with this effect, we observed a relative increase in a predominantly CD4+ T cell infiltrate in the prostate epithelial and stroma of tumors from DKO mice. Collectively, our results offer a preclinical proof of concept for ERK5 as a target to enhance T cell infiltrates in prostate cancer, with possible implications for leveraging immune therapy in this disease.
Mehra R, Udager AM, Ahearn TU, Cao X, Feng FY, Loda M, Petimar JS, Kantoff P, Mucci LA, Chinnaiyan AM.
PMID: 26724257 | DOI: 10.1016/j.eururo.2015.12.003.
The long noncoding RNA SChLAP1 is overexpressed in a subset of prostate cancers (PCa), and high SChLAP1 expression by in situ hybridization (ISH) independently predicts biochemical recurrence after radical prostatectomy. Importantly, although biochemical recurrence is a significant clinical outcome, it is not a validated surrogate for PCa-related mortality. Thus, we evaluated the association between SChLAP1 expression and development of lethal PCa in a large cohort of American men with PCa and long-term follow-up. SChLAP1 ISH was performed on tissue microarrays containing representative formalin-fixed, paraffin-embedded PCa tissue from all patients and scored using a semiquantitative method (ISH score range 0-400). Hazard ratios (HRs) for the association between SChLAP1 expression and time to development of lethal PCa were estimated using multivariable Cox regression analysis. Of the 937 patients evaluated, 89 (9.5%) had high SChLAP1 expression (ISH score ≥100), which in patients treated with radical prostatectomy was strongly associated with development of lethal PCa independent of age, Gleason score, pathologic stage, and PTEN status (HR 2.2, 95% confidence interval 1.1-4.1). These results suggest that SChLAP1 may be a useful tissue-based biomarker for identifying PCa patients at higher risk of lethal progression.
PATIENT SUMMARY:
We examined expression of the RNA molecule SChLAP1 in a large group of prostate cancer patients with long-term follow-up and found that patients with high SChLAP1 expression had a significantly higher chance of developing lethal disease.
Xiao Q, Wu J, Wang WJ, Chen S, Zheng Y, Yu X, Meeth K, Sahraei M, Bothwell ALM, Chen L, Bosenberg M, Chen J, Sexl V, Sun L, Li L, Tang W, Wu D.
PMID: 29431745 | DOI: 10.1038/nm.4496
Immunotherapy offers new options for cancer treatment, but efficacy varies across cancer types. Colorectal cancers (CRCs) are largely refractory to immune-checkpoint blockade, which suggests the presence of yet uncharacterized immune-suppressive mechanisms. Here we report that the loss of adenomatosis polyposis coli (APC) in intestinal tumor cells or of the tumor suppressor PTEN in melanoma cells upregulates the expression of Dickkopf-related protein 2 (DKK2), which, together with its receptor LRP5, provides an unconventional mechanism for tumor immune evasion. DKK2 secreted by tumor cells acts on cytotoxic lymphocytes, inhibiting STAT5 signaling by impeding STAT5 nuclear localization via LRP5, but independently of LRP6 and the Wnt-β-catenin pathway. Genetic or antibody-mediated ablation of DKK2 activates natural killer (NK) cells and CD8+ T cells in tumors, impedes tumor progression, and enhances the effects of PD-1 blockade. Thus, we have identified a previously unknown tumor immune-suppressive mechanism and immunotherapeutic targets particularly relevant for CRCs and a subset of melanomas.
Steiner, I;Flores-Tellez, TDNJ;Mevel, R;Ali, A;Wang, P;Schofield, P;Behan, C;Forsythe, N;Ashton, G;Taylor, C;Mills, IG;Oliveira, P;McDade, SS;Zaiss, DM;Choudhury, A;Lacaud, G;Baena, E;
PMID: 37060563 | DOI: 10.1016/j.celrep.2023.112377
The emergence of castration-resistant prostate cancer remains an area of unmet clinical need. We recently identified a subpopulation of normal prostate progenitor cells, characterized by an intrinsic resistance to androgen deprivation and expression of LY6D. We here demonstrate that conditional deletion of PTEN in the murine prostate epithelium causes an expansion of transformed LY6D+ progenitor cells without impairing stem cell properties. Transcriptomic analyses of LY6D+ luminal cells identified an autocrine positive feedback loop, based on the secretion of amphiregulin (AREG)-mediated activation of mitogen-activated protein kinase (MAPK) signaling, increasing cellular fitness and organoid formation. Pharmacological interference with this pathway overcomes the castration-resistant properties of LY6D+ cells with a suppression of organoid formation and loss of LY6D+ cells in vivo. Notably, LY6D+ tumor cells are enriched in high-grade and androgen-resistant prostate cancer, providing clinical evidence for their contribution to advanced disease. Our data indicate that early interference with MAPK inhibitors can prevent progression of castration-resistant prostate cancer.
Sun, Q;Ma, L;Qiao, J;Wang, X;Li, J;Wang, Y;Tan, A;Ye, Z;Wu, Y;Xi, J;Kang, J;
PMID: 36797653 | DOI: 10.1111/acel.13794
Hippocampal neural stem cell (NSC) proliferation is known to decline with age, which is closely linked to learning and memory impairments. In the current study, we found that the expression level of miR-181a-5p was decreased in the hippocampal NSCs of aged mice and that exogenous overexpression of miR-181a-5p promoted NSC proliferation without affecting NSC differentiation into neurons and astrocytes. The mechanistic study revealed that phosphatase and tensin homolog (PTEN), a negative regulator of the AKT signaling pathway, was the target of miR-181a-5p and knockdown of PTEN could rescue the impairment of NSC proliferation caused by low miR-181a-5p levels. Moreover, overexpression of miR-181a-5p in the dentate gyrus enhanced the proliferation of NSCs and ameliorated learning and memory impairments in aged mice. Taken together, our findings indicated that miR-181a-5p played a functional role in NSC proliferation and aging-related, hippocampus-dependent learning and memory impairments.
Steiner, I;Flores-Tellez, T;Mevel, R;Ali, A;Wang, P;Schofield, P;Forsythe, N;Ashton, G;Taylor, C;Mills, I;Oliveira, P;McDade, S;Zeiss, D;Choudhury, A;Lacaud, G;Baena, E;
| DOI: 10.2139/ssrn.3966640
The emergence of castration resistant prostate cancer is associated with a high mortality and remains an area of unmet clinical need. We recently identified a rare subpopulation of normal prostate progenitor cells, characterized by an intrinsic resistance to androgen-deprivation and marked by the expression of LY6D. We here describe the underlying mechanisms driving castration-resistance of LY6D+ luminal progenitors and their contribution to advanced prostate cancer. We demonstrate that conditional deletion of PTEN in the murine prostate epithelium causes an expansion of transformed LY6D+ progenitor cells in proximal and distal regions of the prostate without impairing stem cell properties. Transcriptomic analyses of LY6D+ luminal cells identified an autocrine positive feed-back loop, based on the secretion of amphiregulin (AREG), further increasing cellular fitness and organoid formation. Pharmacological interference with AREG-activated MAPK-signaling overcomes the castration-resistant properties of LY6D+ cells with a near complete suppression of organoid formation. Notably, LY6D+ tumor cells are enriched in prostate specimens from high-grade and androgen-resistant prostate cancer, providing clinical evidence for their contribution to advanced and also metastatic disease. Our data indicate that the prospective identification of LY6D+ cells could allow for an early interference with MAPK-inhibitors to prevent the emergence of castration-resistant prostate cancer.
Lagarde-Lenon, MS;Aron, M;
PMID: 36894368 | DOI: 10.1016/j.humpath.2023.02.011
Primary female urethral carcinoma (PUC-F) accounts for less than 1% of all genitourinary malignancies and comprises a histologically diverse group of tumors that are usually associated with poor prognosis. The carcinomas documented at this site include adenocarcinoma (clear cell adenocarcinoma, columnar cell carcinoma, and Skene gland adenocarcinoma), urothelial carcinoma (UCa), and squamous cell carcinoma (SCC). Recent studies have shown adenocarcinomas to be the most common type of primary urethral carcinoma in females. As most of the urethral carcinomas morphologically resemble carcinomas arising from surrounding pelvic organs or metastases, these should be ruled out before making the diagnosis of PUC-F. These tumors are currently staged according to the 8th edition of the American Joint Committee on Cancer (AJCC) staging system. However, the AJCC system has limitations, including the staging of tumors involving the anterior wall of the urethra. Staging systems like the recently proposed histology-based female urethral carcinoma staging system (UCS) takes into account the unique histological landmarks of the female urethra to better stratify pT2 and pT3 tumors into prognostic groups, that correlate with clinical outcomes including recurrence rates, disease-specific survival and overall survival. Further larger multi-institutional cohorts are however required to validate the results of this staging system. There is very limited information regarding the molecular profiling of PUC-F. Thirty-one percent of clear cell adenocarcinomas have been reported to show PIK3CA alterations, whereas 15% of adenocarcinomas show PTEN mutations. Higher tumor mutational burden and PD-L1 staining have been reported in UCa and SCC. Although multimodality treatment is usually recommended in locally advanced and metastatic disease, the role of immunotherapy and targeted therapy is promising in select PUC-F cases.
Kim, H;Saikia, J;Monte, K;Ha, E;Romaus-Sanjurjo, D;Sanchez, J;Moore, A;Hernaiz-Llorens, M;Chavez-Martinez, C;Agba, C;Li, H;Lusk, D;Cervantes, K;Zheng, B;
PMID: 36865182 | DOI: 10.21203/rs.3.rs-2588274/v1
The corticospinal tract (CST) is clinically important for the recovery of motor functions after spinal cord injury. Despite substantial progress in understanding the biology of axon regeneration in the central nervous system (CNS), our ability to promote CST regeneration remains limited. Even with molecular interventions, only a small proportion of CST axons regenerate1. Here we investigate this heterogeneity in the regenerative ability of corticospinal neurons following PTEN and SOCS3 deletion with patch-based single cell RNA sequencing (scRNA-Seq)2,3, which enables deep sequencing of rare regenerating neurons. Bioinformatic analyses highlighted the importance of antioxidant response and mitochondrial biogenesis along with protein translation. Conditional gene deletion validated a role for NFE2L2 (or NRF2), a master regulator of antioxidant response, in CST regeneration. Applying Garnett4, a supervised classification method, to our dataset gave rise to a Regenerating Classifier (RC), which, when applied to published scRNA-Seq data, generates cell type- and developmental stage-appropriate classifications. While embryonic brain, adult dorsal root ganglion and serotonergic neurons are classified as Regenerators, most neurons from adult brain and spinal cord are classified as Non-regenerators. Adult CNS neurons partially revert to a regenerative state soon after injury, which is accelerated by molecular interventions. Our data indicate the existence of universal transcriptomic signatures underlying the regenerative abilities of vastly different neuronal populations, and further illustrate that deep sequencing of only hundreds of phenotypically identified CST neurons has the power to reveal new insights into their regenerative biology.
Lagarde-Lenon, MS;Aron, M;
PMID: 36037997 | DOI: 10.1016/j.humpath.2022.08.003
Primary female urethral carcinoma (PUC-F) accounts for less than 1% of all genitourinary malignancies and comprises a histologically diverse group of tumors that are usually associated with poor prognosis. The carcinomas documented at this site include adenocarcinoma (clear cell adenocarcinoma, columnar cell carcinoma and Skene gland adenocarcinoma), urothelial carcinoma (UCa) and squamous cell carcinoma (SCC). Recent studies have shown adenocarcinomas to be the most common type of primary urethral carcinoma in females. Since most of the urethral carcinomas morphologically resemble carcinomas arising from surrounding pelvic organs or metastases, these should be ruled out before making the diagnosis of PUC-F. These tumors are currently staged according to the 8th edition of the American Joint Committee on Cancer (AJCC) staging system. However, the AJCC system has limitations, including the staging of tumors involving the anterior wall of the urethra. Staging systems like the recently proposed histology based female urethral carcinoma staging system (UCS) takes into account the unique histological landmarks of the female urethra to better stratify pT2 and pT3 tumors into prognostic groups, that correlate with clinical outcomes including recurrence rates, disease-specific and overall survival. Further larger multi-institutional cohorts are however required to validate the results of this staging system. There is very limited information regarding the molecular profiling of PUC-F. 31% of clear cell adenocarcinomas have been reported to show PIK3CA alterations, while 15% of adenocarcinomas show PTEN mutations. Higher tumor mutational burden (TMB) and PD-L1 staining have been reported in UCa and SCC. Although multimodality treatment is usually recommended in locally advanced and metastatic disease, the role of immunotherapy and targeted therapy is promising in select PUC-F cases.
Axin2+ peribiliary glands in the periampullary region generate biliary epithelial stem cells that give rise to ampullary carcinoma
Hayata, Y;Nakagawa, H;Kurosaki, S;Kawamura, S;Matsushita, Y;Hayakawa, Y;Suzuki, N;Hata, M;Tsuboi, M;Kinoshita, H;Miyabayashi, K;Mizutani, H;Nakagomi, R;Ikenoue, T;Hirata, Y;Arita, J;Hasegawa, K;Tateishi, K;Koike, K;
PMID: 33465373 | DOI: 10.1053/j.gastro.2021.01.028
Peribiliary glands (PBGs), clusters of epithelial cells residing in the submucosal compartment of extrahepatic bile ducts, have been suggested as biliary epithelial stem/progenitor cell niche; however, evidence to support this claim is limited due to a lack of PBG-specific markers. We therefore sought to identify PBG-specific markers to investigate the potential role of PBGs as stem/progenitor cell niches, as well as an origin of cancer. We examined the expression pattern of the Wnt target gene Axin2 in extrahepatic bile ducts. We then applied lineage tracing to investigate whether Axin2-expressing cells from PBGs contribute to biliary regeneration and carcinogenesis using Axin2-CreERT mice. Wnt signaling activation, marked by Axin2, was limited to PBGs located in the periampullary region. Lineage tracing revealed that Axin2-expressing periampullary PBG cells are capable of self-renewal and supplying new biliary epithelial cells (BECs) to the luminal surface. Additionally, the expression pattern of Axin2 and the mature ductal cell marker CK19 was mutually exclusive in periampullary region, and fate tracing of CK19+ luminal surface BECs revealed gradual replacement by CK19- cells, further supporting the continuous replenishment of new BECs from PBGs to the luminal surface. We also found that Wnt signal enhancer R-spondin3 secreted from Myh11-expressing stromal cells, corresponding to human sphincter of Oddi, maintained the periampullary Wnt signal-activating niche. Notably, introduction of PTEN deletion into Axin2+ PBG cells, but not CK19+ luminal surface BECs, induced ampullary carcinoma whose development was suppressed by Wnt inhibitor. A specific cell population receiving Wnt-activating signal in periampullary PBGs functions as biliary epithelial stem/progenitor cells and also cellular origin of ampullary carcinoma.
