Human gastric microbiota transplantation recapitulates premalignant lesions in germ-free mice.

OBJECTIVE: Gastric cancer (GC) is a leading cause of cancer-related mortality. Although microbes besides Helicobacter pylori may also contribute to gastric carcinogenesis, wild-type germ-free (GF) mouse models investigating the role of human gastric microbiota in the process are not yet available. We aimed to evaluate the histopathological features of GF mouse stomachs transplanted with gastric microbiota from patients with different gastric disease states and their relationships with the microbiota. DESIGN: Microbiota profiles in corpus and antrum tissues and gastric fluid from 12 patients with gastric dysplasia or GC were analysed. Thereafter, biopsied corpus and antrum tissues and gastric fluid from patients (n=15 and n=12, respectively) with chronic superficial gastritis, intestinal metaplasia or GC were inoculated into 42 GF C57BL/6 mice. The gastric microbiota was analysed by amplicon sequencing. Histopathological features of mouse stomachs were analysed immunohistochemically at 1 month after inoculation. An independent set of an additional 15 GF mice was also analysed at 1 year. RESULTS: The microbial community structures of patients with dysplasia or GC in the corpus and antrum were similar. The gastric microbiota from patients with intestinal metaplasia or GC selectively colonised the mouse stomachs and induced premalignant lesions: loss of parietal cells and increases in inflammation foci, in F4/80 and Ki-67 expression, and in CD44v9/GSII lectin expression. Marked dysplastic changes were noted at 1 year post inoculation. CONCLUSION: Major histopathological features of premalignant changes are reproducible in GF mice transplanted with gastric microbiota from patients with intestinal metaplasia or GC. Our results suggest that GF mice are useful for analysing the causality of associations reported in human gastric microbiome studies.

WFDC2 Promotes Spasmolytic Polypeptide-Expressing Metaplasia Through the Up-Regulation of IL33 in Response to Injury.

BACKGROUND & AIMS: WAP 4-disulfide core domain protein 2 (WFDC2), also known as human epididymis protein 4, is a small secretory protein that is highly expressed in fibrosis and human cancers, particularly in the ovaries, lungs, and stomach. However, the role of WFDC2 in carcinogenesis is not fully understood. The present study aimed to investigate the role of WFDC2 in gastric carcinogenesis with the use of preneoplastic metaplasia models. METHODS: Three spasmolytic polypeptide-expressing metaplasia (SPEM) models were established in both wild-type and Wfdc2-knockout mice with DMP-777, L635, and high-dose tamoxifen, respectively. To reveal the functional role of WFDC2, we performed transcriptomic analysis with DMP-777-treated gastric corpus specimens. RESULTS: Wfdc2-knockout mice exhibited remarkable resistance against oxyntic atrophy, SPEM emergence, and accumulation of M2-type macrophages in all 3 SPEM models. Transcriptomic analysis revealed that Wfdc2-knockout prevented the up-regulation of interleukin-33 (IL33) expression in the injured mucosal region of SPEM models. Notably, supplementation of recombinant WFDC2 induced IL33 production and M2 macrophage polarization, and ultimately promoted SPEM development. Moreover, long-term treatment with recombinant WFDC2 was able to induce SPEM development. CONCLUSIONS: WFDC2 expressed in response to gastric injury promotes SPEM through the up-regulation of IL33 expression. These findings provide novel insights into the role of WFDC2 in gastric carcinogenesis.

Antagonists of the serotonin receptor 5A target human breast tumor initiating cells.

BACKGROUND: Breast tumor initiating cells (BTIC) are stem-like cells that initiate and sustain tumor growth, and drive disease recurrence. Identifying therapies targeting BTIC has been hindered due primarily to their scarcity in tumors. We previously reported that BTIC frequency ranges between 15% and 50% in multiple mammary tumors of 3 different transgenic mouse models of breast cancer and that this frequency is maintained in tumor cell populations cultured in serum-free, chemically defined media as non-adherent tumorspheres. The latter enabled high-throughput screening of small molecules for their capacity to affect BTIC survival. Antagonists of several serotonin receptors (5-HTRs) were among the hit compounds. The most potent compound we identified, SB-699551, selectively binds to 5-HT5A, a Gαi/o protein coupled receptor (GPCR). METHODS: We evaluated the activity of structurally unrelated selective 5-HT5A antagonists using multiple orthogonal assays of BTIC frequency. Thereafter we used a phosphoproteomic approach to uncover the mechanism of action of SB-699551. To validate the molecular target of the antagonists, we used the CRISPR-Cas9 gene editing technology to conditionally knockout HTR5A in a breast tumor cell line. RESULTS: We found that selective antagonists of 5-HT5A reduced the frequency of tumorsphere initiating cells residing in breast tumor cell lines and those of patient-derived xenografts (PDXs) that we established. The most potent compound among those tested, SB-699551, reduced the frequency of BTIC in ex vivo assays and acted in concert with chemotherapy to shrink human breast tumor xenografts in vivo. Our phosphoproteomic experiments established that exposure of breast tumor cells to SB-699551 elicited signaling changes in the canonical Gαi/o-coupled pathway and the phosphoinositide 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) axis. Moreover, conditional mutation of the HTR5A gene resulted in the loss of tumorsphere initiating cells and BTIC thus mimicking the effect of SB-699551. CONCLUSIONS: Our data provide genetic, pharmacological and phosphoproteomic evidence consistent with the on-target activity of SB-699551. The use of such agents in combination with cytotoxic chemotherapy provides a novel therapeutic approach to treat breast cancer.

Loss of Rab25 promotes the development of skin squamous cell carcinoma through the dysregulation of integrin trafficking.

Rab25 can function as both a tumor suppressor and a tumor promoter across different tissues. This study sought to clarify the role of Rab25 as a tumor suppressor in skin squamous cell carcinoma (SCC). Rab25 loss was closely associated with neoplastic transition in both humans and mice. Rab25 loss was well correlated with increased cell proliferation and poor differentiation in human SCC. While Rab25 knockout (KO) in mice did not induce spontaneous tumor formation, it did significantly accelerate tumor generation and promote malignant transformation in a mouse two-stage skin carcinogenesis model. Xenografting of a Rab25-deficient human keratinocyte cell line, HaCaT, also elicited neoplastic transformation. Notably, Rab25 deficiency led to dysregulation of integrins ß1, ß4, and α6, which matched well with increased epidermal proliferation and impaired desmosome-tight junction formation. Rab25 deficiency induced impairment of integrin recycling, leading to the improper expression of integrins. In line with this, significant attenuation of integrin ß1, ß4, and α6 expression was identified in human SCCs where Rab25 was deficient. Collectively, these results suggest that loss of Rab25 promotes the development and neoplastic transition of SCC through dysregulation of integrin trafficking. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Combination Therapy of Microneedle Fractional Radiofrequency and Topical Poly-Lactic Acid for Acne Scars: A Randomized Controlled Split-Face Study.

BACKGROUND: Acne scarring occurs at a young age and causes distress for many patients. Various treatment modalities have been tried. OBJECTIVE: This study investigated the efficacy of combination therapy with topical poly-lactic acid and microneedle fractional radiofrequency (MFRF) for acne scars. MATERIALS AND METHODS: Patients with acne scars on both the cheeks were included. Poly-lactic acid was applied to the acne scars on one side of the face before MFRF treatment. The other side of the face was treated with MFRF and normal saline. Patients received 3 treatment sessions and were evaluated based on visual assessment and patient satisfaction. After the last treatment, objective scar assessment of scar smoothness, size, brightness, and overall improvement was performed. RESULTS: Both acne scar assessment scores and patient satisfaction were better with combination therapy (p = .036 and p = .009, respectively) than with monotherapy. Combination therapy resulted in significantly better efficacy for scar smoothness (p < .001), scar size (p = .003), and overall improvement (p < .001), but not for brightness (p = .151). CONCLUSION: Combination therapy resulted in significantly better clinical outcomes, including better scar smoothness and smaller scar size. Therefore, we believe this combination therapy is a safe and effective treatment for acne scars.

Impact of preoperative calculation of nephron volume loss on future of partial nephrectomy techniques; planning a strategic roadmap for improving functional preservation and securing oncological safety.

OBJECTIVES: To assess the correlation of the resected and ischaemic volume (RAIV), which is a preoperatively calculated volume of nephron loss, with the amount of postoperative renal function (PRF) decline after minimally invasive partial nephrectomy (PN) in a multi-institutional dataset. PATIENTS AND METHODS: We identified 348 patients from March 2005 to December 2013 at six institutions. Data on all cases of laparoscopic (n = 85) and robot-assisted PN (n = 263) performed were retrospectively gathered. Univariable and multivariable linear regression analyses were used to identify the associations between various time points of PRF and the RAIV, as a continuous variable. RESULTS: The mean (sd) RAIV was 24.2 (29.2) cm3 . The mean preoperative estimated glomerular filtration rate (eGFR) and the eGFRs at postoperative day 1, 6 and 36 months after PN were 91.0 and 76.8, 80.2 and 87.7 mL/min/1.73 m2 , respectively. In multivariable linear regression analysis, the amount of decline in PRF at follow-up was significantly correlated with the RAIV (ß 0.261, 0.165, 0.260 at postoperative day 1, 6 and 36 months after PN, respectively). This study has the limitation of its retrospective nature. CONCLUSION: Preoperatively calculated RAIV significantly correlates with the amount of decline in PRF during long-term follow-up. The RAIV could lead our research to the level of prediction of the amount of PRF decline after PN and thus would be appropriate for assessing the technical advantages of emerging techniques.

In vivo 4-1BB deficiency in myeloid cells enhances peripheral T cell proliferation by increasing IL-15.

4-1BB signals are considered positive regulators of T cell responses against viruses and tumors, but recent studies suggest that they have more complex roles in modulating T cell responses. Although dual roles of 4-1BB signaling in T cell responses have been suggested, the underlying mechanisms are still not fully understood. In this study, we tested whether 4-1BB expression affected T cell responses differently when expressed in myeloid versus lymphoid cells in vivo. By assessing the proliferation of 4-1BB(+/+) and 4-1BB(-/-) T cells in lymphocyte-deficient RAG2(-/-) and RAG2(-/-)4-1BB(-/-) mice, we were able to compare the effects on T cell responses of 4-1BB expression on myeloid versus T cells. Surprisingly, adoptively transferred T cells were more responsive in tumor-bearing RAG2(-/-)4-1BB(-/-) mice than in RAG2(-/-) mice, and this enhanced T cell proliferation was further enhanced if the T cells were 4-1BB deficient. Dendritic cells (DCs) rather than NK or tissue cells were the myeloid lineage cells primarily responsible for the enhanced T cell proliferation. However, individual 4-1BB(-/-) DCs were less effective in T cell priming in vivo than 4-1BB(+/+) DCs; instead, more DCs in the secondary lymphoid organs of RAG2(-/-)4-1BB(-/-) mice appeared to induce the enhanced T cell proliferation by producing and transpresenting more IL-15. Therefore, we conclude that in vivo 4-1BB signaling of myeloid cells negatively regulates peripheral T cell responses by limiting the differentiation of DCs and their accumulation in secondary lymphoid organs.

Authentic GITR Signaling Fails To Induce Tumor Regression unless Foxp3+ Regulatory T Cells Are Depleted.

The glucocorticoid-induced TNFR family-related protein (GITR, TNFRSF18, CD357) is expressed on effector and regulatory T (Treg) cells. Previous studies demonstrated that GITR triggering by anti-GITR mAb enhanced T and B cell-mediated immune responses. GITR-deficient T cells, however, also proliferate more than normal T cells, and this effect is unexplained. Because the activities of mAbs are controlled by their Fc regions, the true effect of GITR signaling needs to be determined by examining its interaction with authentic ligand. Therefore, we generated a pentamerized form of the GITRL extracellular domain (pGITRL) for ligation to GITR and compared its effect on T cells with that of anti-GITR mAb. The pGITRL was more effective than anti-GITR mAb in enhancing the proliferation of effector and regulatory cells in vitro and in vivo. Nonetheless, the growth of MC38 adenocarcinoma cells in vivo was only suppressed for initial 15 d by pGITRL, whereas it was suppressed indefinitely by anti-GITR mAb. Detailed analysis revealed that pGITRL induced extensive proliferation of Foxp3(+)CD4(+) Treg cells and led to the accumulation of activated Treg cells in tumor tissue and draining lymph nodes. Because GITR signaling could not neutralize the suppressive activity of activated Treg cells, pGITRL seems to lose its adjuvant effect when sufficient activated Treg cells have accumulated in the lymph nodes and tumor tissue. Indeed, the antitumor effects of pGITRL were markedly enhanced by depleting CD4(+) cells. These results suggest that GITR signaling has stimulatory effects on effector T cells and inhibitory effects through Treg cells.

CRIg signals induce anti-intracellular bacterial phagosome activity in a chloride intracellular channel 3-dependent manner.

Macrophages provide a first line of defense against bacterial infection by engulfing and killing invading bacteria, but intracellular bacteria such as Listeria monocytogenes (LM) can survive in macrophages by various mechanisms of evasion. Complement receptor of the immunoglobulin (CRIg), a C3b receptor, binds to C3b on opsonized bacteria and facilitates clearance of the bacteria by promoting their uptake. We found that CRIg signaling induced by agonistic anti-CRIg mAb enhanced the killing of intracellular LM by macrophages, and that this occurred in LM-containing phagosomes. Chloride intra-cellular channel 3 CLIC3, an intracellular chloride channel protein, was essential for CRIg-mediated LM killing by directly interacting with the cytoplasmic domain of CRIg, and the two proteins colocalized on the membranes of LM-containing vacuoles. CLIC3(-/-) mice were as susceptible to LM as CRIg(-/-) mice. These findings identify a mechanism embedded in the process by which macrophages take up opsonized bacteria that prevents the bacteria from evading cell-mediated killing.

Immunohistochemical evaluation of keratins and involucrin in differentiating between palmoplantar pustulosis and pompholyx.

BACKGROUND: Palmoplantar pustulosis (PPP) and pompholyx are chronic diseases characterized by pustules and vesicles on the palms and soles. These disorders often have similar clinicopathological features, which lead to diagnostic difficulties. We aimed to investigate the expression patterns of keratins and involucrin in PPP and pompholyx using immunohistochemical staining. METHODS: Skin biopsies from patients with PPP (n = 40) and pompholyx (n = 22) were immunohistochemically analyzed for Keratin 5, 9, 14, and involucrin expression. RESULTS: K5 expression was higher in PPP than in pompholyx, with diffusely positive expression in the basal, spinous, and granular layers. K14 expression did not differ between groups. K9 expression was observed near the pompholyx vesicle (P = 0.014) and stratum spinosum (P < 0.001) but was almost absent around PPP pustules. Involucrin expression was diffused around the PPP pustules and partially around the pompholyx vesicles, but without statistical significance (P = 0.123). Involucrin expression was elevated in the basal layer of the PPP compared with that in the pompholyx (P = 0.023). CONCLUSION: PPP and pompholyx exhibited distinctive differentiation in the expression of K5, K9, and involucrin.

4-1BB triggering ameliorates experimental autoimmune encephalomyelitis by modulating the balance between Th17 and regulatory T cells.

Agonistic anti-4-1BB Ab is known to ameliorate experimental autoimmune encephalomyelitis. 4-1BB triggering typically leads to the expansion of CD8(+) T cells, which produce abundant IFN-γ, and this in turn results in IDO-dependent suppression of autoimmune responses. However, because neutralization of IFN-γ or depletion of CD8(+) T cell only partially abrogates the effect of 4-1BB triggering, we sought to identify an additional mechanism of 4-1BB-triggered suppression of autoimmune responses using IFN-γ- or IFN-γR-deficient mice. 4-1BB triggering inhibited the generation of Th17 cells that is responsible for experimental autoimmune encephalomyelitis induction and progression, and increased Foxp3(+)CD4(+) regulatory T (Treg) cells, particularly among CD4(+) T cells. This was not due to a direct effect of 4-1BB signaling on CD4(+) T cell differentiation: 4-1BB signaling not only reduced Th17 cells and increased Treg cells in wild-type mice, which could be due to IFN-γ production by the CD8(+) T cells, but also did so in IFN-γ-deficient mice, in that case by downregulating IL-6 production. These results show that although secondary suppressive mechanisms evoked by 4-1BB triggering are usually masked by the strong effects of IFN-γ, 4-1BB signaling seems to modulate autoimmune responses by a number of mechanisms, and modulation of the Th17 versus Treg cell balance is one of those mechanisms.

Role of Nox4 in Mitigating Inflammation and Fibrosis in Dextran Sulfate Sodium-Induced Colitis.

BACKGROUND & AIMS: Fibrosis development in ulcerative colitis is associated directly with the severity of mucosal inflammation, which increases the risk of colorectal cancer. The transforming growth factor-ß (TGF-ß) signaling pathway is an important source of tissue fibrogenesis, which is stimulated directly by reactive oxygen species produced from nicotinamide adenine dinucleotide phosphate oxidases (NOX). Among members of the NOX family, NOX4 expression is up-regulated in patients with fibrostenotic Crohn's disease (CD) and in dextran sulfate sodium (DSS)-induced murine colitis. The aim of this study was to determine whether NOX4 plays a role in fibrogenesis during inflammation in the colon using a mouse model. METHODS: Acute and recovery models of colonic inflammation were performed by DSS administration to newly generated Nox4-/- mice. Pathologic analysis of colon tissues was performed, including detection of immune cells, proliferation, and fibrotic and inflammatory markers. RNA sequencing was performed to detect differentially expressed genes between Nox4-/- and wild-type mice in both the untreated and DSS-treated conditions, followed by functional enrichment analysis to explore the molecular mechanisms contributing to pathologic differences during DSS-induced colitis and after recovery. RESULTS: Nox4-/- mice showed increased endogenous TGF-ß signaling in the colon, increased reactive oxygen species levels, intensive inflammation, and an increased fibrotic region after DSS treatment compared with wild-type mice. Bulk RNA sequencing confirmed involvement of canonical TGF-ß signaling in fibrogenesis of the DSS-induced colitis model. Up-regulation of TGF-ß signaling affects collagen activation and T-cell lineage commitment, increasing the susceptibility for inflammation. CONCLUSIONS: Nox4 protects against injury and plays a crucial role in fibrogenesis in DSS-induced colitis through canonical TGF-ß signaling regulation, highlighting a new treatment target.

Corrigendum: Role of histamine-mediated macrophage differentiation in clearance of metastatic bacterial infection.

[This corrects the article DOI: 10.3389/fimmu.2023.1290191.].

Role of histamine-mediated macrophage differentiation in clearance of metastatic bacterial infection.

Macrophages are highly heterogeneous immune cells with a role in maintaining tissue homeostasis, especially in activating the defense response to bacterial infection. Using flow cytometric and single-cell RNA-sequencing analyses of peritoneal cells, we here show that small peritoneal macrophage and immature macrophage populations are enriched in histamine-deficient (Hdc -/-) mice, characterized by a CD11bmiF4/80loCCR2+MHCIIhi and CD11bloF4/80miTHBS1+IL-1α+ phenotype, respectively. Molecular characterization revealed that immature macrophages represent an abnormally differentiated form of large peritoneal macrophages with strong inflammatory properties. Furthermore, deficiency in histamine signaling resulted in significant impairment of the phagocytic activity of peritoneal macrophage populations, conferring high susceptibility to bacterial infection. Collectively, this study reveals the importance of histamine signaling in macrophage differentiation at the molecular level to maintain tissue homeostasis, offering a potential therapeutic target for bacterial infection-mediated diseases.

Histamine Signaling Is Essential for Tissue Macrophage Differentiation and Suppression of Bacterial Overgrowth in the Stomach.

BACKGROUND & AIMS: Histamine in the stomach traditionally is considered to regulate acid secretion but also has been reported to participate in macrophage differentiation, which plays an important role in tissue homeostasis. Therefore, this study aimed to uncover the precise role of histamine in mediating macrophage differentiation and in maintaining stomach homeostasis. METHODS: Here, we expand on this role using histidine decarboxylase knockout (Hdc-/-) mice with hypertrophic gastropathy. In-depth in vivo studies were performed in Hdc-/- mice, germ-free Hdc-/- mice, and bone-marrow-transplanted Hdc-/- mice. The stomach macrophage populations and function were characterized by flow cytometry. To identify stomach macrophages and find the new macrophage population, we performed single-cell RNA sequencing analysis on Hdc+/+ and Hdc-/- stomach tissues. RESULTS: Single-cell RNA sequencing and flow cytometry of the stomach cells of Hdc-/- mice showed alterations in the ratios of 3 distinct tissue macrophage populations (F4/80+Il1bhigh, F4/80+CD93+, and F4/80-MHC class IIhighCD74high). Tissue macrophages of the stomachs of Hdc-/- mice showed impaired phagocytic activity, increasing the bacterial burden of the stomach and attenuating hypertrophic gastropathy in germ-free Hdc-/- mice. The transplantation of bone marrow cells of Hdc+/+ mice to Hdc-/- mice recovered the normal differentiation of stomach macrophages and relieved the hypertrophic gastropathy of Hdc-/- mice. CONCLUSIONS: This study showed the importance of histamine signaling in tissue macrophage differentiation and maintenance of gastric homeostasis through the suppression of bacterial overgrowth in the stomach.

Peripheral 4-1BB signaling negatively regulates NK cell development through IFN-gamma.

Stimulation of 4-1BB (CD137) was shown to produce strong anticancer effects in vivo. In contrast, 4-1BB-deficient (4-1BB(-/-)) B6 mice are remarkably resistant to tumor growth. We set out to determine the mechanisms involved in these seemingly contradictory observations. We found that the therapeutic effects of 4-1BB triggering were mainly dependent on CD8(+) T cells and partially on NK cells, whereas CD8(+) T and NK cells were equally needed to suppress tumor growth in 4-1BB(-/-) mice. Cellular analysis showed that the frequency and number of NK cells in the spleen and bone marrow were decreased by 4-1BB triggering but were increased in the absence of 4-1BB signaling in tumor-challenged mice. The 4-1BB-mediated downregulation of NK cell development was primarily dependent on IFN-gamma, which was produced by peripheral CD8(+) T and NK cells. The suppression of NK cell development by 4-1BB-mediated IFN-gamma production occurred in the bone marrow. As 4-1BB signaling increased in the periphery, more CD8(+) T cells but fewer NK cells contributed to the antitumor immunity. As 4-1BB signaling decreased, more NK cells participated in the antitumor immunity. We conclude that 4-1BB signaling results in a shift of the dominant type of immune cell in antitumor immunity from the innate NK cell to the adaptive CD8(+) T cell and that the level of IFN-gamma is critical for this 4-1BB-mediated shift.

A New Murine Liver Fibrosis Model Induced by Polyhexamethylene Guanidine-Phosphate.

Liver fibrosis is part of the wound healing process to help the liver recover from the injuries caused by various liver-damaging insults. However, liver fibrosis often progresses to life-threatening cirrhosis and hepatocellular carcinoma. To overcome the limitations of current in vivo liver fibrosis models for studying the pathophysiology of liver fibrosis and establishing effective treatment strategies, we developed a new mouse model of liver fibrosis using polyhexamethylene guanidine phosphate (PHMG-p), a humidifier sterilizer known to induce lung fibrosis in humans. Male C57/BL6 mice were intraperitoneally injected with PHMG-p (0.03% and 0.1%) twice a week for 5 weeks. Subsequently, liver tissues were examined histologically and RNA-sequencing was performed to evaluate the expression of key genes and pathways affected by PHMG-p. PHMG-p injection resulted in body weight loss of ~15% and worsening of physical condition. Necropsy revealed diffuse fibrotic lesions in the liver with no effect on the lungs. Histology, collagen staining, immunohistochemistry for smooth muscle actin and collagen, and polymerase chain reaction analysis of fibrotic genes revealed that PHMG-p induced liver fibrosis in the peri-central, peri-portal, and capsule regions. RNA-sequencing revealed that PHMG-p affected several pathways associated with human liver fibrosis, especially with upregulation of lumican and IRAK3, and downregulation of GSTp1 and GSTp2, which are closely involved in liver fibrosis pathogenesis. Collectively we demonstrated that the PHMG-p-induced liver fibrosis model can be employed to study human liver fibrosis.

Hexa-BODIPY-cyclotriphosphazene based nanoparticle for NIR fluorescence/photoacoustic dual-modal imaging and photothermal cancer therapy.

Theranostic, which integrates the diagnosis and tumor treatment in tandem, is an emerging strategy in cancer treatment. Here, we report a novel and unique theranostic nanoparticle, HBCP NP, based on hexa-BODIPY cyclophosphazene (HBCP). Due to the unique bulky molecular structure of HBCP, this nanoparticle can simultaneously perform near-infrared (NIR) fluorescence imaging and photoacoustic imaging (PAI). Interestingly, since reactive oxygen species (ROS) generation of HBCP NPs is completely inhibited, 'safe' fluorescence imaging is possible without the risk of cell damage even under laser irradiation. Finally, NIR fluorescence imaging and PAI in 4T1 tumor-bearing mice demonstrated selective accumulation of HBCP NPs at tumor sites. In addition, HBCP NPs exhibited excellent photothermal effects under high-power laser irradiation, achieving effective tumor growth inhibition.

Single-cell analysis of gastric pre-cancerous and cancer lesions reveals cell lineage diversity and intratumoral heterogeneity.

Single-cell transcriptomic profiles analysis has proposed new insights for understanding the behavior of human gastric cancer (GC). GC offers a unique model of intratumoral heterogeneity. However, the specific classes of cells involved in carcinogenetic passage, and the tumor microenvironment of stromal cells was poorly understood. We characterized the heterogeneous cell population of precancerous lesions and gastric cancer at the single-cell resolution by RNA sequencing. We identified 10 gastric cell subtypes and showed the intestinal and diffuse-type cancer were characterized by different cell population. We found that the intestinal and diffuse-type cancer cells have the differential metaplastic cell lineages: intestinal-type cancer cells differentiated along the intestinal metaplasia lineage while diffuse-type cancer cells resemble de novo pathway. We observed an enriched CCND1 mutation in premalignant disease state and discovered cancer-associated fibroblast cells harboring pro-stemness properties. In particular, tumor cells could be categorized into previously proposed molecular subtypes and harbored specific subtype of malignant cell with high expression level of epithelial-myofibroblast transition which was correlated with poor clinical prognosis. In addition to intratumoral heterogeneity, the analysis revealed different cellular lineages were responsible for potential carcinogenetic pathways. Single-cell transcriptomes analysis of gastric pre-cancerous lesions and cancer may provide insights for understanding GC cell behavior, suggesting potential targets for the diagnosis and treatment of GC.

Gut microbiota of the young ameliorates physical fitness of the aged in mice.

BACKGROUND: Aging is a natural process that an organism gradually loses its physical fitness and functionality. Great efforts have been made to understand and intervene in this deteriorating process. The gut microbiota affects host physiology, and dysbiosis of the microbial community often underlies the pathogenesis of host disorders. The commensal microbiota also changes with aging; however, the interplay between the microbiota and host aging remains largely unexplored. Here, we systematically examined the ameliorating effects of the gut microbiota derived from the young on the physiology and phenotypes of the aged. RESULTS: As the fecal microbiota was transplanted from young mice at 5 weeks after birth into 12-month-old ones, the thickness of the muscle fiber and grip strength were increased, and the water retention ability of the skin was enhanced with thickened stratum corneum. Muscle thickness was also marginally increased in 25-month-old mice after transferring the gut microbiota from the young. Bacteria enriched in 12-month-old mice that received the young-derived microbiota significantly correlated with the improved host fitness and altered gene expression. In the dermis of these mice, transcription of Dbn1 was most upregulated and DBN1-expressing cells increased twice. Dbn1-heterozygous mice exhibited impaired skin barrier function and hydration. CONCLUSIONS: We revealed that the young-derived gut microbiota rejuvenates the physical fitness of the aged by altering the microbial composition of the gut and gene expression in muscle and skin. Dbn1, for the first time, was found to be induced by the young microbiota and to modulate skin hydration. Our results provide solid evidence that the gut microbiota from the young improves the vitality of the aged. Video Abstract.