Nucleic acid therapeutics
Kuo, C;Nikan, M;Yeh, ST;Chappell, AE;Tanowitz, M;Seth, PP;Prakash, TP;Mullick, AE;
PMID: 35612431 | DOI: 10.1089/nat.2021.0105
We evaluated the potential of AGTR1, the principal receptor for angiotensin II (Ang II) and a member of the G protein-coupled receptor family, for targeted delivery of antisense oligonucleotides (ASOs) in cells and tissues with abundant AGTR1 expression. Ang II peptide ASO conjugates maintained robust AGTR1 signaling and receptor internalization when ASO was placed at the N-terminus of the peptide, but not at C-terminus. Conjugation of Ang II peptide improved ASO potency up to 12- to 17-fold in AGTR1-expressing cells. Additionally, evaluation of Ang II conjugates in cells lacking AGTR1 revealed no enhancement of ASO potency. Ang II peptide conjugation improves potency of ASO in mouse heart, adrenal, and adipose tissues. The data presented in this report add to a growing list of approaches for improving ASO potency in extrahepatic tissues.
Endocr Pathol. 2019 Jan 2.
Chu YH, Hardin H, Eickhoff J, Lloyd RV.
PMID: 30600442 | DOI: 10.1007/s12022-018-9564-1
Recent studies suggest onco-regulatory roles for two long non-coding RNAs (lncRNAs), MALAT1 and HOTAIR, in various malignancies; however, these lncRNAs have not been previously examined in neuroendocrine neoplasms (NENs) of gastroenteropancreatic origins (GEP-NENs). In this study, we evaluated the expressions and prognostic significance of MALAT1 and HOTAIR in 83 cases of GEP-NENs (60 grade 1, 17 grade 2, and 6 grade 3 tumors) diagnosed during the years 2005-2017. Expression levels of MALAT1 and HOTAIR were digitally quantitated in assembled tissue microarray slides labeled by chromogenic in situ hybridization (ISH) using InForm 1.4.0 software. We found diffuse nuclear expression of both HOTAIR and MALAT1 in all primary tumors of GEP-NENs with variable intensities. By multivariate model which adjusted for age and histologic grade, high expression of HOTAIR was associated with lower presenting T and M stages and subsequent development of metastases (P < 0.05). MALAT1 expression was associated with presenting T stage and development of metastases (P < 0.05). In summary, MALAT1 and HOTAIR are commonly expressed in GEP-NENs. High expression of either lncRNA showed grade-independent associations with clinically less aggressive disease.
WNT signaling in pre-granulosa cells is required for ovarian folliculogenesis and female fertility
Development (Cambridge, England)
Habara, O;Logan, CY;Kanai-Azuma, M;Nusse, R;Takase, HM;
PMID: 33914868 | DOI: 10.1242/dev.198846
In mammalian ovaries, immature oocytes are reserved in primordial follicles until their activation for potential ovulation. Precise control of primordial follicle activation (PFA) is essential for reproduction, but how this is achieved is unclear. Here, we show that canonical wingless-type MMTV integration site family (WNT) signaling is pivotal for pre-granulosa cell (pre-GC) activation during PFA. We identified several WNT ligands expressed in pre-GCs that act in an autocrine manner. Inhibition of WNT secretion from pre-GCs/GCs by conditional knockout (cKO) of the wntless (Wls) gene led to female infertility. In Wls cKO mice, GC layer thickness was greatly reduced in growing follicles, which resulted in impaired oocyte growth with both an abnormal, sustained nuclear localization of forkhead box O3 (FOXO3) and reduced phosphorylation of ribosomal protein S6 (RPS6). Constitutive stabilization of β-catenin (CTNNB1) in pre-GCs/GCs induced morphological changes of pre-GCs from a squamous into a cuboidal form, though it did not influence oocyte activation. Our results reveal that canonical WNT signaling plays a permissive role in the transition of pre-GCs to GCs, which is an essential step to support oocyte growth.
Cellular and molecular gastroenterology and hepatology
Kim, TY;Kim, S;Kim, Y;Lee, YS;Lee, S;Lee, SH;Kweon, MN;
PMID: 34971821 | DOI: 10.1016/j.jcmgh.2021.12.015
Dietary signals are known to modulate stemness and tumorigenicity of intestinal progenitors; however, the impact of a high-fat diet (HFD) on the intestinal stem cell (ISC) niche and its association with colorectal cancer remains unclear. Thus, we aimed to investigate how a HFD affects the ISC niche and its regulatory factors.Mice were fed a purified diet (PD) or HFD for 2 months. The expression levels of ISC-related markers, ISC-supportive signals, and Wnt2b were assessed with real-time quantitative polymerase chain reaction, in situ hybridization, and immunofluorescence staining. RNA sequencing and metabolic function were analyzed in mesenchymal stromal cells (MSCs) from PD- and HFD-fed mice. Fecal microbiota were analyzed by 16s rRNA sequencing. Bile salt hydrolase activity and bile acid (BA) levels were measured.We found that expression of CD44 and Wnt signal-related genes was higher in the colonic crypts of HFD-fed mice than in those fed a PD. Within the ISC niche, MSCs were expanded and secreted predominant levels of Wnt2b in the colon of HFD-fed mice. Of note, increased energy metabolism and cancer-associated fibroblast (CAF)-like properties were found in the colonic MSCs of HFD-fed mice. Moreover, colonic MSCs from HFD-fed mice promoted the growth of tumorigenic properties and accelerated the expression of cancer stem cell (CSC)-related markers in colon organoids. In particular, production of primary and secondary BAs was increased through the expansion of bile salt hydrolase-encoding bacteria in HFD-fed mice. Most importantly, BAs-FXR interaction stimulated Wnt2b production in colonic CAF-like MSCs.HFD-induced colonic CAF-like MSCs play an indispensable role in balancing the properties of CSCs through activation of the BAs-FXR axis.
Chang HL Bamodu OA Ong JR, Lee WH, Yeh CT, Tsai JT
PMID: 32326045 | DOI: 10.3390/cells9041020
BACKGROUND:
With recorded under-performance of current standard therapeutic strategies as highlighted by high rates of post-treatment (resection or local ablation) recurrence, resistance to chemotherapy, poor overall survival, and an increasing global incidence, hepatocellular carcinoma (HCC) constitutes a medical challenge. Accumulating evidence implicates the presence of HCC stem cells (HCC-SCs) in HCC development, drug-resistance, recurrence, and progression. Therefore, treatment strategies targeting both HCC-SCs and non-CSCs are essential.
METHODS:
Recently, there has been an increasing suggestion of MALAT1 oncogenic activity in HCC; however, its role in HCC stemness remains unexplored. Herein, we investigated the probable role of MALAT1 in the SCs-like phenotype of HCC and explored likely molecular mechanisms by which MALAT1 modulates HCC-SCs-like and metastatic phenotypes.
RESULTS:
We showed that relative to normal, cirrhotic, or dysplastic liver conditions, MALAT1 was aberrantly expressed in HCC, similar to its overexpression in Huh7, Mahlavu, and SK-Hep1 HCC cells lines, compared to the normal liver cell line THLE-2. We also demonstrated a positive correlation between MALAT1 expression and poor cell differentiation status in HCC using RNAscope. Interestingly, we demonstrated that shRNA-mediated silencing of MALAT1 concomitantly downregulated the expression levels of ?-catenin, Stat3, c-Myc, CK19, vimentin, and Twist1 proteins, inhibited HCC oncogenicity, and significantly suppressed the HCC-SCs-related dye-effluxing potential of HCC cells and reduced their ALDH-1 activity, partially due to inhibited MALAT1-?-catenin interaction. Additionally, using TOP/FOP (TCL/LEF-Firefly luciferase) Flash, RT-PCR, and western blot assays, we showed that silencing MALAT1 downregulates ?-catenin expression, dysregulates the canonical Wnt signaling pathway, and consequently attenuates HCC tumorsphere formation efficiency, with concurrent reduction in CD133+ and CD90+ HCC cell population, and inhibits tumor growth in SK-Hep1-bearing mice. Conclusions: Taken together, our data indicate that MALAT1/Wnt is a targetable molecular candidate, and the therapeutic targeting of MALAT1/Wnt may constitute a novel promising anticancer strategy for HCC treatment.
Cell Host Microbe. 2018 Dec 12.
Lee YS, Kim TY, Kim Y, Lee SH, Kim S, Kang SW, Yang JY, Baek IJ, Sung YH, Park YY, Hwang SW, O E, Kim KS, Liu S, Kamada N, Gao N, Kweon MN.
PMID: 30543778 | DOI: 10.1016/j.chom.2018.11.002
Symbionts play an indispensable role in gut homeostasis, but underlying mechanisms remain elusive. To clarify the role of lactic-acid-producing bacteria (LAB) on intestinal stem-cell (ISC)-mediated epithelial development, we fed mice with LAB-type symbionts such as Bifidobacterium and Lactobacillus spp. Here we show that administration of LAB-type symbionts significantly increased expansion of ISCs, Paneth cells, and goblet cells. Lactate stimulated ISC proliferation through Wnt/β-catenin signals of Paneth cells and intestinal stromal cells. Moreover, Lactobacillus plantarum strains lacking lactate dehydrogenase activity, which are deficient in lactate production, elicited less ISC proliferation. Pre-treatment with LAB-type symbionts or lactate protected mice in response to gut injury provoked by combined treatments with radiation and a chemotherapy drug. Impaired ISC-mediated epithelial development was found in mice deficient of the lactate G-protein-coupled receptor, Gpr81. Our results demonstrate that LAB-type symbiont-derived lactate plays a pivotal role in promoting ISC-mediated epithelial development in a Gpr81-dependent manner.
Cholesterol-functionalized DNA/RNA heteroduplexes cross the blood-brain barrier and knock down genes in the rodent CNS
Nagata, T;Dwyer, CA;Yoshida-Tanaka, K;Ihara, K;Ohyagi, M;Kaburagi, H;Miyata, H;Ebihara, S;Yoshioka, K;Ishii, T;Miyata, K;Miyata, K;Powers, B;Igari, T;Yamamoto, S;Arimura, N;Hirabayashi, H;Uchihara, T;Hara, RI;Wada, T;Bennett, CF;Seth, PP;Rigo, F;Yokota, T;
PMID: 34385691 | DOI: 10.1038/s41587-021-00972-x
Achieving regulation of endogenous gene expression in the central nervous system (CNS) with antisense oligonucleotides (ASOs) administered systemically would facilitate the development of ASO-based therapies for neurological diseases. We demonstrate that DNA/RNA heteroduplex oligonucleotides (HDOs) conjugated to cholesterol or α-tocopherol at the 5' end of the RNA strand reach the CNS after subcutaneous or intravenous administration in mice and rats. The HDOs distribute throughout the brain, spinal cord and peripheral tissues and suppress the expression of four target genes by up to 90% in the CNS, whereas single-stranded ASOs conjugated to cholesterol have limited activity. Gene knockdown was observed in major CNS cell types and was greatest in neurons and microglial cells. Side effects, such as thrombocytopenia and focal brain necrosis, were limited by using subcutaneous delivery or by dividing intravenous injections. By crossing the blood-brain barrier more effectively, cholesterol-conjugated HDOs may overcome the limited efficacy of ASOs targeting the CNS without requiring intrathecal administration.
Yu Q, Hardin H, Chu YH, Rehrauer W, Lloyd RV.
PMID: 31119524 | DOI: 10.1007/s12022-019-9578-3
Parathyroid adenomas are slow growing benign neoplasms associated with hypercalcemia, while atypical parathyroid adenomas and parathyroid carcinomas are uncommon tumors and their histologic features may overlap with parathyroid adenomas. LncRNAs participate in transcription and in epigenetic or post-transcriptional regulation of gene expression, and probably contribute to carcinogenesis. We analyzed a group of normal, hyperplastic, and neoplastic parathyroid lesions to determine the best immunohistochemical markers to characterize these lesions and to determine the role of selected lncRNAs in tumor progression. A tissue microarray consisting of 111 cases of normal parathyroid (n = 14), primary hyperplasia (n = 15), secondary hyperplasia (n = 10), tertiary hyperplasia (n = 11), adenomas (n = 50), atypical adenomas (n = 7), and carcinomas (n = 4) was used. Immunohistochemical staining with antibodies against chromogranin A, synaptophysin, parathyroid hormone, and insulinoma-associated protein 1(INSM1) was used. Expression of lncRNAs including metastasis-associated lung adenocarcinoma transcript one (MALAT1), HOX transcript antisense intergenic RNA (HOTAIR), and long intergenic non-protein coding regulator of reprograming (Linc-ROR or ROR) was also analyzed by in situ hybridization and RT-PCR. All of the parathyroid tissues were positive for parathyroid hormone, while most cases were positive for chromogranin A (98%). Synaptophysin was expressed in only 12 cases (11%) and INMS1 was negative in all cases. ROR was significantly downregulated during progression from normal, hyperplastic, and adenomatous parathyroid to parathyroid carcinomas. These results show that parathyroid hormone and chromogranin A are useful markers for parathyroid neoplasms, while synaptophysin and INSM1 are not very sensitive broad-spectrum markers for these neoplasms. LincRNA ROR may function as a tumor suppressor during parathyroid tumor progression.
Basham KJ, Rodriguez S, Turcu AF, Lerario AM, Logan CY, Rysztak MR, Gomez-Sanchez CE, Breault DT, Koo BK, Clevers H, Nusse R, Val P, Hammer GD.
PMID: 30692207 | DOI: 10.1101/gad.317412.118
Spatiotemporal control of Wnt signaling is essential for the development and homeostasis of many tissues. The transmembrane E3 ubiquitin ligases ZNRF3 (zinc and ring finger 3) and RNF43 (ring finger protein 43) antagonize Wnt signaling by promoting degradation of frizzled receptors. ZNRF3 and RNF43 are frequently inactivated in human cancer, but the molecular and therapeutic implications remain unclear. Here, we demonstrate that adrenocortical-specific loss of ZNRF3, but not RNF43, results in adrenal hyperplasia that depends on Porcupine-mediated Wnt ligand secretion. Furthermore, we discovered a Wnt/β-catenin signaling gradient in the adrenal cortex that is disrupted upon loss of ZNRF3. Unlike β-catenin gain-of-function models, which induce high Wnt/β-catenin activation and expansion of the peripheral cortex, ZNRF3 loss triggers activation of moderate-level Wnt/β-catenin signaling that drives proliferative expansion of only the histologically and functionally distinct inner cortex. Genetically reducing β-catenin dosage significantly reverses the ZNRF3-deficient phenotype. Thus, homeostatic maintenance of the adrenal cortex is dependent on varying levels of Wnt/β-catenin activation, which is regulated by ZNRF3.