Stem Cell Markers CXCR-4 and CD133 Predict Aggressive Phenotype and Their Double Positivity Indicates Poor Prognosis of Oral Squamous Cell Carcinoma.

The activation of the SDF-1/CXCR-4 pathway is crucial for the invasion and metastasis of oral cancer cells. The CXCR-4 positive cells possess stem cell characteristics and express the cancer stem cell marker, CD133, in tumors of colon and pancreas. Despite several studies, the co-expression of CXCR-4 and CD133 and its significance is still largely unknown in oral cancer. Therefore, we aimed to investigate the impact of CXCR-4 and CD133 double positivity in the prognosis of oral cancer. The significance of PKC-δ, one of the key signaling molecules that regulates CXCR-4, was also analyzed. Immunohistochemistry and double immunofluorescence was used to investigate the co-localization of CXCR-4, PKC-δ and CD133 in the human tissues and cell lines of oral squamous cell carcinoma. The expression of CXCR-4, PKC-δ and CD133 were found to be higher in poorly differentiated and lymph node metastasis-positive cases. Interestingly, CXCR-4 positive cells showed positive staining for PKC-δ and CD133 in oral cancer tissue and cell lines. Moreover, CXCR-4+/CD133+ and CXCR-4+/PKC-δ+ double positive cases have the worst survival. We discovered, for the first time, that patients with expression of both CXCR-4 and CD133 have a lower survival rate, and CXCR-4+/CD133+, as well as CXCR-4+/PKC-δ+ double positivity, can be utilized to predict poor prognosis. CXCR-4, PKC-δ and CD133 might regulate aggressiveness and invasion of oral cancer cells.

Effects of combined treatment with Indomethacin and Juglone on AOM/DSS induced colon carcinogenesis in Balb/c mice: Roles of inflammation and apoptosis.

AIM: Indomethacin [IND] is reported to treat colon cancer. However, continuous exposure to IND causes gastric ulceration, an adverse side effect in humans. This study implies the therapeutic effect of IND and juglone [JUG] against colon carcinogenesis, without gastric ulceration - an adverse side effect of IND. MATERIALS AND METHODS: Adult male Balb/C mice were divided into six groups randomly: control, AOM/DSS-induced, IND-treated, JUG-treated, IND + JUG-treated and drug-control. Levels of serum markers, haematoxylin & eosin staining to observe tissue architecture, toluidine blue staining to detect mast cells expression, Masson's trichrome and sirius-red staining were used to detect the collagen deposition. RT-PCR and western blot analysis were carried out to detect inflammation and apoptosis. KEY FINDINGS: IND + JUG effectively decreased the levels of serum markers: CEA, AFP, LDH, AST and ALT. Although, IND restored colonic architecture by regulating the accumulation of mast cell and collagen content, it causes gastric ulceration. To address this adverse effect of IND, JUG was given along with IND and was shown to alleviate IND-induced gastric ulceration. AOM/DSS induced animals showed increased expression of inflammatory molecules - TNFα, NFκB and Cox-2, apoptosis regulator - Bcl-2 and decreased expression of pro-apoptotic molecules - Bad, Bax and caspase3; whereas, IND and JUG treated groups showed decreased inflammatory expression with increased expression of pro-apoptotic molecules. SIGNIFICANCE: IND and JUG reduce the inflammatory activity and induce apoptotic cell death, while JUG effectively prevents IND induced gastric ulceration. These findings establish that a combination of IND + JUG may serve as a promising treatment regimen for colon cancer.

Indomethacin and juglone inhibit inflammatory molecules to induce apoptosis in colon cancer cells.

Colorectal cancer (CRC) is the third most common fatal cancer. Indomethacin, a nonsteroidal anti-inflammatory drug, is known to reduce the occurrence of CRC. This study evaluated the potential anticolon cancer effects of juglone (5-hydroxy-1,4-naphthoquinone) in combination with indomethacin. Human colon adenocarcinoma cells (HT29) were subjected to treatment with indomethacin, juglone, and a combination of both. Morphological analysis, cell cycle regulation, and dual staining using acridine orange and ethidium bromide in control and treated cells revealed the apoptotic potential of these compounds. Bcl2 and inflammatory molecules (tumor necrosis factor-α, nuclear factor kappa B, and Cox-2) were found to be decreased with a concomitant increase in the expression of proapoptotic molecules (Bad, Bax, cytochrome c, and PUMA) as a result of the molecular regulation of Wnt, Notch, and peroxisome proliferator-activated receptor-γ signaling. Treatment with juglone was not as effective as with indomethacin; however, a combination of both was shown to be more effective, suggesting that juglone may be considered for therapeutic intervention of colon cancer.

Expression of chemokines in macrophage polarization and downregulation of NFκB in aorta allow macrophage polarization by diosgenin in atherosclerosis.

M1 macrophages serve one edge as proinflammatory and M2 macrophages serve the other edge as an anti-inflammatory macrophage. It appears that a related "switch" in macrophage morphology may also happen in the course of atherosclerosis, which has not yet been elucidated. An atherogenic diet (AD) was given to rats, and induction of macrophage differentiation and the nuclear localization of nuclear factor-kappa B (NFκB) were investigated by Western blot and immunofluorescence. Chemokines were analyzed using an antibody array with 32 target proteins. M2 macrophage transformation was confirmed in diosgenin-treated aorta by immunofluorescence and was validated in vitro using THP-1 cells. MAC387 (macrophage marker) and NFκBp65 (inflammatory hub) were upregulated in oxidatively-modified low-density lipoprotein (OxyLDL) and AD-induced condition. Macrophage differentiation, which induced the formation of inflammatory mediators, was not significantly suppressed by the inhibition of NFκB using dexamethasone. M1 macrophage polarization was identified in OxyLDL-induced monocytes, which are proinflammatory in nature, whereas M2 macrophage polarization was noticed in diosgenin-treated monocytes, which exhibit anti-inflammatory properties. M1-and M2-specific chemokines were analyzed using chemokine antibody array. Furthermore, the expression of proinflammatory macrophage (M1) was noticed in AD-induced aorta and anti-inflammatory macrophage (M2) was observed in diosgenin-treated aorta. This is the first report where, unifying the mechanism of diosgenin as aan nti-atherosclerotic and the expression of M1 and M2 specific chemokines is shown by downregulating NFκB and not by preventing the differentiation of monocyte into a macrophage, but by allowing macrophage to differentiate into M2, which aids in preventing the atherosclerotic progression.

Modulation of complex coordinated molecular signaling by 5HT and a cocktail of inhibitors leads to ovarian maturation of Penaeus monodon in captivity.

In aquaculture practices, prawn cultivation holds the major share and Penaeus monodon is the main species cultured. The decline in production of P. monodon is mainly due to the limited availability of domesticated broodstock, which is attributed to its reproductive cycle, controlled by complex coordinated signaling mechanisms. Unilateral eyestalk ablation of domesticated females held in captivity is done to induce ovary development, which has certain disadvantages, including a high rate of mortality. Thus, developing alternative techniques for eyestalk ablation in captive broodstock is necessary to induce maturation of ovary. This study exemplifies the role of 5HT along with a cocktail of inhibitors (U0126, Rp-cAMP, and LY294002) in inducing ovarian maturation. In this study, inhibition of pERK by U0126 inhibited vitellogenesis-inhibiting hormone (VIH), which in turn led to the overexpression of vitellogenin. 5HT induces steroidogenesis (estradiol-17ß) through induction of the gonadotropin-releasing hormone by activating calcium-calmodulin signaling. Steroidogenesis is also aided by synthesis of StAR protein. Estradiol-17ß stimulates the formation of the maturation-promoting factor (MPF) complex by cdc25 activation and Myt1 inactivation. LY294002 aids in keeping cdc25 activated by inhibiting calcium-calmodulin induced phosphorylation of Akt which is a negative regulator of mitogen-activated protein kinases. VIH induced activation of Myt1, through protein kinase A (PKA), was inhibited by Rp-cAMP which inhibits adenylate cyclase, thus stabilizing the activated MPF complex. To conclude, the coordinated effect of inhibitors and 5HT accelerates the development of ovary from previtellogenic to matured oocytes, yielding high quality and quantity larvae compared with eyestalk-ablated P. monodon.

Inhibition of nuclear translocation of notch intracellular domain (NICD) by diosgenin prevented atherosclerotic disease progression.

Notch signaling plays a pivotal role in homeostasis and cardiovascular development. The role of notch signaling in atherosclerosis cannot be complete without analysing the key role of notch in macrophages, which trigger the inflammatory response and subsequent plaque formation in atherosclerosis. Diosgenin showed its anti-atherosclerotic property by the unifying mechanism of suppressing the expression of notch signaling pathway, particularly the nuclear translocation of notch intracellular domain (NICD) in aorta and in differentiated macrophage cells. It is further confirmed by the inhibition of NICD by DAPT (N-[N-(3, 5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester), which also restricted the differentiation of macrophage. Hence, inhibition of nuclear translocation of NICD by diosgenin aids in preventing atherosclerosis.

Differential cytotoxic activity of Quercetin on colonic cancer cells depends on ROS generation through COX-2 expression.

Quercetin is a bioactive compound with anti-inflammatory, antioxidant and anticancer properties. This study exemplifies the differential cytotoxic activity of Quercetin on two human colonic cancer cell lines, HT29 and HCT15. IC50 of Quercetin for HT29 and HCT15 cells were 42.5 µM and 77.4 µM, respectively. Activation of caspase-3, increased level of cytosolic cytochrome c, decreased levels of pAkt, pGSK-3ß and cyclin D1 in 40 µM Quercetin treated HT29 cells alone. Though, nuclear translocation of NFkB was increased in 40 µM Quercetin treated HT29 and HCT15 cells, over expression of COX-2 was observed in 40 µM Quercetin treated HT29 cells, whereas, Quercetin treated HCT15 cells did not expressed COX-2. Increased generation of reactive oxygen species (ROS) was observed only in Quercetin treated HT29 cells, which is due to over expression of COX-2, as COX-2 silencing inhibited Quercetin induced apoptosis and ROS generation. Insilico analysis provided evidence that Quercetin could partially inhibit COX-2 enzyme by binding to subunit A which has peroxidase activity and serves as source of ROS. However, Quercetin showed minimal effect on normal intestinal epithelial cells i,e IEC-6. To conclude, differential sensitivity of two cancer cells, HT29 and HCT15, to Quercetin depends on COX-2 dependent ROS generation that induces apoptosis and inhibits cell survival.

Shigella dysenteriae infection activates proinflammatory response through ß-catenin/NF-κB signaling pathway.

Shigella dysenteriae (S.dysenteriae) the causative agent of bacillary dysentery invades the human colonic epithelium resulting in severe intestinal inflammatory response and epithelial destruction. However, the mechanism by which S.dysenteriae infection regulates proinflammatory cytokines during intestinal inflammation is still obscure. In this study, we evaluated whether the interaction of ß-catenin and NF-κB regulates proinflammatory cytokines TNF-α and IL-8 by modulating GSK-3ß activity during S.dysenteriae infection in rat ileal loop model. Here we demonstrated that S.dysenteriae infection stimulate ß-catenin degradation which in turn decreased the association between NF-κB and ß-catenin. Also, we showed that S.dysenteriae infection increased GSK-3ß kinase activity which in turn phosphorylates ß-catenin for its degradation by ubiquitination and upregulates IL-8 through NF-κB activation thereby leading to inflammation. Thus these findings revealed the role of ß-catenin/ NF-κB and GSK-3ß in modulating the inflammatory response during bacterial infection and also showed that ß-catenin acts as a critical regulator of inflammation.

Morin, a dietary flavonoid, exhibits anti-fibrotic effect and induces apoptosis of activated hepatic stellate cells by suppressing canonical NF-κB signaling.

In experimental liver fibrosis, activated hepatic stellate cells (HSCs) play a central role and thus, induction of apoptosis of activated HSCs is a promising therapeutic strategy for liver fibrosis. The present study was designed to elucidate the molecular mechanisms of the pro-apoptotic effects of morin, a dietary flavonoid, in vitro and in vivo. Culture-activated human HSCs (LX-2 cells) were treated with morin (50 µM) for 24 and 48 h, and the mechanism of cell death induced by morin was evaluated. Also, the anti-fibrotic and pro-apoptotic effect of morin in diethylnitrosamine (DEN)-induced fibrotic rats were determined. Morin induced apoptosis in cultured LX-2 cells by preventing the nuclear translocation of nuclear factor-κBp65 (NF-κBp65) by inhibiting NF-κB activation via inhibition of IκBα degradation and thereby suppressing anti-apoptotic proteins and activating caspases. In fibrotic rats, morin treatment resulted in inhibition of canonical NF-κB signaling and induction of apoptosis, mainly by downregulating Bcl-2, upregulating Bax and cyt c and by activation of caspase-9 and caspase-3. Translocation of phosphatidylserine to the outer membrane, altered nuclear morphology and DNA fragmentation confirmed the induction of apoptosis by morin. Overall, morin treatment ameliorated experimental liver fibrosis, most likely through induction of apoptosis by inhibiting canonical NF-κB signaling in activated HSCs. It is therefore postulated that morin is a potential therapeutic candidate for liver fibrosis.

Association of differential ß-catenin expression with Oct-4 and Nanog in oral squamous cell carcinoma and their correlation with clinicopathological factors and prognosis.

BACKGROUND: The re-expression of pluripotent markers (Oct-4 and Nanog) and the reactivation of stem cell-related pathways in oral carcinoma have been well researched. However, the relationship between the stem cell signaling molecule ß-catenin and pluripotent markers Oct-4 and Nanog in oral cancer is yet to be studied in detail. Therefore, we have investigated the correlation among Oct-4, Nanog, and ß-catenin in oral squamous cell carcinoma, which, in turn, could provide valuable insight into its prognostic significance. METHODS: The immunohistochemical analysis was performed for 60 cases of oral cancer to study the expression pattern of Oct-4, Nanog, and ß-catenin. Whereas immunofluorescence analysis was used to investigate the co-localization of ß-catenin with Oct-4 and Nanog in oral carcinoma tissues and H314 cell line. Finally, co-immunoprecipitation analysis was used to study the possible interaction between ß-catenin and Oct-4 in oral carcinoma cells. RESULTS: ß-catenin, Oct-4, and Nanog showed significant correlation with lymph node metastasis, stage, grade, and prognosis in oral squamous cell carcinoma. Interestingly, a significant positive correlation was found among the expression of Oct-4, Nanog, and ß-catenin. Moreover, the interaction between ß-catenin and Oct-4 was observed in oral cancer. CONCLUSION: The positive correlation among Oct-4, Nanog, and ß-catenin suggests their coordinated role in maintaining proliferation in oral carcinoma cells. The interaction between ß-catenin and Oct-4 may be a crucial event in oral carcinogenesis. On the other hand, ß-catenin, Oct-4, and Nanog could be used as independent prognostic markers of oral squamous cell carcinoma.

Prognostic significance of neural stem cell markers, Nestin and Musashi-1, in oral squamous cell carcinoma: expression pattern of Nestin in the precancerous stages of oral squamous epithelium.

BACKGROUND: Besides the tissue-specific stem cell markers, neural and hematopoietic stem cell markers were found to play an important role in carcinogenesis. Based on this background, we have investigated the expression pattern and prognostic significance of neural stem cell markers, Nestin and Musashi-1, in oral cancer. METHODS: We used immunohistochemistry and immunofluorescence analyses to study the expression pattern and correlation between Nestin and Musashi-1 in oral squamous cell carcinoma. The Kaplan-Meier method was used to construct overall and disease-free survival curves, and the differences were calculated using log-rank test. RESULTS: Nestin expression was gradually increased in the transformation stages of oral cancer. Both Nestin and Musashi-1 expressions were associated with higher stage and poorly differentiated status of oral carcinoma. Interestingly, Nestin and Musashi-1 double positive cases showed statistically highly significant correlation with poorer survival of oral carcinoma patients. CONCLUSIONS: Expression of Nestin in the preneoplastic lesions indicates its role in the transformation of oral squamous epithelium. Clinicopathological and survival analyses suggest that Nestin and Musashi-1 might be associated with invasion, differentiation and poorer survival in oral squamous cell carcinoma. In addition to their role as independent prognostic indicators, Nestin and Musashi-1 double positivity can be used to select high-risk cases for effective therapy and this is the novel finding of this study. CLINICAL RELEVANCE: Nestin and Musashi-1 are found to be independent prognostic markers of oral cancer, and they might be used as molecular targets for effective therapy.

Synergistic association of Notch and NFκB signaling and role of Notch signaling in modulating epithelial to mesenchymal transition in colorectal adenocarcinoma.

Notch1 signaling plays a key role in normal developmental processes and in cancer. The association between Notch activation and development of cancer has been well documented. Notch activation and outcome of the disease depend upon the crosstalk with other regulatory pathways including Nuclear Factor kappa B (NFκB) pathway. In this study, we have investigated the interaction of Notch intracellular domain (NICD) with NFκBp65 in colorectal cancer which resulted in the upregulation of Bcl-xL resulting in the inhibition of apoptosis. Mesenchymal marker Slug expression and down regulation of E-cadherin, an epithelial phenotypic marker were demonstrated in colon cancer tissues. The study was also illustrated by using the gamma secretase inhibitor, N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (DAPT) in HT29 cells. Immunohistochemistry (NICD, NFκBp65, and Slug) and double immunofluorescence analysis (NICD, NFκBp65) revealed that NICD and NFκBp65 were highly expressed in HT29 cells and in tumor tissue compared to normal tissue. Slug and Bcl-xL protein expressions were significantly reduced in DAPT treated HT 29 cells. Immunoprecipitation and dual staining emphasized the strong interaction of NICD with NFκBp65 in adenocarcinoma than in normal tissue. It appeared that Notch1 and NFκB could independently contribute to tumor progression. However, their interaction and synergism might be the determinants that would affect the outcome of the disease and therapeutic interventions.

Colocalization of ß-catenin with Notch intracellular domain in colon cancer: a possible role of Notch1 signaling in activation of CyclinD1-mediated cell proliferation.

The Wnt and Notch1 signaling pathways play major roles in intestinal development and tumorigenesis. Sub-cellular localization of ß-catenin has been implicated in colorectal carcinogenesis. However, the ß-catenin and Notch intracellular domain (NICD) interaction has to be addressed. Immunohistochemistries of ß-catenin, NICD, and dual immunofluorescence of ß-catenin and NICD were analyzed in colorectal tissues and HT29 cell line. Moreover, real-time PCR analysis of CyclinD1, Hes1 and MUC2 was done in HT29 cells upon N-[N-(3, 5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (DAPT) treatment. Dual staining emphasized the strong interaction of ß-catenin and NICD in adenoma and adenocarcinoma than in normal tissues. Hes1 transcript levels were decreased 1.5- and 7.1-fold in 12.5 and 25 µM DAPT-treated HT29 cells. CyclinD1 transcript levels decreased 1.2- and 1.6-fold, and MUC2 transcript level increased 4.3- and 7.5-fold in 12.5 and 25 µM DAPT-treated HT29 cells. The results of this study showed that the sub-cellular localization of ß-catenin converges with NICD inducing proliferation through the activation of CyclinD1 and Hes1. Moreover, the inhibition of Notch1 signaling by DAPT leads to the arrest of cell proliferation and induces apoptosis leading to the upregulation of MUC2, a secretory cell lineage marker.

Morin ameliorates chemically induced liver fibrosis in vivo and inhibits stellate cell proliferation in vitro by suppressing Wnt/ß-catenin signaling.

The anti-fibrotic effect of morin was examined in LX-2 cells (culture-activated human hepatic stellate cells) and in diethylnitrosamine induced rat model of liver fibrosis. The in vitro study was designed to determine whether morin affects the survival of cultured LX-2 cells, while the in vivo study was designed to evaluate the antioxidant and anti-fibrotic efficacy of morin on diethylnitrosamine induced liver fibrosis in male albino Wistar rat. The activities of liver function enzymes in serum, liver lipid peroxide levels, activities of serum antioxidant enzymes and liver architecture were monitored to cast light on the antioxidant and hepatoprotective nature of morin. To establish the anti-fibrotic effects of morin, the levels of key Wnt signaling molecules which are strongly associated with the signal transduction pathway of HSC activation were measured. Overall, from the in vitro results, it was observed that morin at 50 µM concentration inhibited the proliferation of cultured LX-2 cells, inhibited Wnt signaling and induced G1 cell cycle arrest. The in vivo results further confirmed that morin by downregulating the expressions of GSK-3ß, ß-catenin and cyclin D1 ameliorated DEN-induced liver fibrosis. Hence morin could be employed as a promising chemopreventive natural supplement for liver fibrosis.

Distribution and homing pattern of c-kit+ Sca-1+ CXCR4+ resident cardiac stem cells in neonatal, postnatal, and adult mouse heart.

INTRODUCTION: The origin of heart-forming cells and their roles in organ development have fascinated biologists for over a century. C-X-C chemokine receptor type 4 plays a crucial role during embryonic development and in maintaining the stem cell niche and homing. The aim of the present was to study the expression pattern of resident cardiac stem cell markers and their homing factor in neonatal, postnatal, and adult mouse heart. METHODS: Cardiac stem cell protein expression was analyzed using immunofluorescence, immunohistochemistry, and Western blotting. The messenger ribonucleic acid expression of cardiac stem cell markers c-kit, stem cell antigen-1, and homing factor C-X-C chemokine receptor type 4 was quantitatively analyzed using quantitative polymerase chain reaction. Data were analyzed using Student's t test and two-way analysis using SPSS software. RESULTS: Stem cell antigen-1- and c-kit-positive cell populations were heterogeneously distributed in the adult and postnatal hearts but scattered in the neonatal heart. The expression of c-kit showed a significant difference between right and left atrium, though it was higher compared to ventricles. The homing factor C-X-C chemokine receptor type 4 expression was higher in the neonatal heart than in the postnatal heart but was not detectable in the adult heart. CONCLUSIONS: The present study reveals the distribution of cardiac stem cells in the different compartments of the heart and significant reduction in their number in adult heart. Cardiac stem cells are higher in the atrium than in the ventricle, suggesting the atria as the source of cardiac stem cell.

Notch signalling in cardiovasculogenesis: insight into their role in early cardiovascular development.

The role of Notch signalling in congenital cardiovascular disease is evident by the identification of human mutations in several Notch signalling components, which also indicates the importance of activated Notch pathway in cardiovascular biology. Therefore, the aim of the present study is to investigate the expression pattern of the components of Notch signalling molecules and their role in mice embryonic heart and vascular development. Group A: normal control pregnant mice, group B: pregnant mice were injected with DMSO, group C: DAPT were subcutaneously injected to pregnant mice. The morphological and molecular changes of trabeculation-defective phenotype were analysed using histological, scanning electron microscope, immunoblot, immunolocalization and reverse transcriptase-PCR. E15.5 DAPT-treated mice revealed that there was a major reduction in the formation of septal walls between the ventricular chambers compared with normal control pregnant mice. VEGF expression was found in the DAPT treated and wild-type embryonic artery, whereas notch target genes GATA4, Hey1 expression were not found in the DAPT treated mice embryo. The role of Notch in ventricular development is supported by the trabeculation-defective phenotype seen in standard and endocardial-specific inhibition of Notch targets. The present study reveals the significant role of Notch signalling during the formation of ventricular septum and proper development of endothelial cell lineage and its precursor in mice cardiogenesis.

Induction of ovarian maturation in Penaeus monodon by molecular signal interventional approach.

Vitellogenin (VTG) synthesis in the hepatopancreas and ovary is negatively regulated by vitellogenesis-inhibiting hormone (VIH) produced in the neurosecretory cell of X-organ/sinus gland complex of the eyestalks of penaeid shrimp. Eyestalk ablation is used commercially to induce ovarian maturation in shrimps which leads to an eventual loss of the spawner. The aim of the present study was to understand the molecular mechanism of VIH regulation in ovarian development and its inhibition of VTG gene expression by using a MEK-specific inhibitor (U0126). The real-time quantitative PCR results showed VTG mRNA level was progressively increased in the ovary and hepatopancreas of unilateral eyestalk-ablated and inhibitor-treated shrimps. Western blot analysis also showed that phosphoMEK was detected only in the unilateral eyestalk-ablated and control shrimp, whereas phospho-MEK was not detected in inhibitor-treated shrimp. DAX-1, SF-1, and StAR expression correlated with changes in VIH mRNA and altered phospho-ERK levels. This is consistent with the hypothesis that suppression of DAX-1 results in SF-1-mediated StAR protein upregulation of estradiol that is implicated in vitellogenesis. This is the first report that demonstrates the molecular mechanism of VIH suppression via MEK pathway to induce ovarian maturation in female Penaeus monodon by molecular signal intervention, a less-invasive method than traditional eyestalk ablation.

Differential expression of gastric MUC5AC in colonic epithelial cells: TFF3-wired IL1 ß/Akt crosstalk-induced mucosal immune response against Shigella dysenteriae infection.

An understanding of the signaling mechanism(s) that regulate the differential expression of gastric mucin MUC5AC in colonic epithelial cells would contribute significantly to investigations of its role in colonic mucosa infected with the bacterial pathogen Shigella dysenteriae. Here we show that S. dysenteriae-Sinduced expression of interleukin-1ß upregulates MUC2 expression and the differential expression of MUC5AC. Differential expression of MUC5AC involves crosstalk between interleukin-1ß and Akt, whereby the trefoil factor family peptide TFF3 activates Akt by phosphorylation of EGFR. TFF3 also downregulates E-cadherin expression, causing accumulation of ß-catenin in the cytosol. Phosphorylation of GSK-3ß (inactivated) by activated Akt inhibits ubiquitylation of ß-catenin, leading to its nuclear translocation, which then induces the expression of MUC5AC and cyclin D1. Accumulation of cyclin D1 alters the cell cycle, promoting cell survival and proliferation. Human colon HT29MTX cells, which overexpress MUC5AC, were resistant to adherence and invasion of S. dysenteriae when compared with other mucin-secreting HT29 cell types. Thus, during infection with S. dysenteriae, crosstalk between interleukin-1ß and Akt wired by TFF3 induces expression of MUC5AC in colonic epithelial cells. Differentially expressed gastric MUC5AC aids in mucosal clearance of S. dysenteriae, inhibiting adherence and invasion of the pathogen to colonic epithelial cells, which protects the host.

Phosphorylation of the gastric tumor suppressor RUNX3 following H. pylori infection results in its localization to the cytoplasm.

As H. pylori infection progresses, intestinal metaplasia (IM), a key event in gastric carcinogenesis, develops in the stomach. The mechanism by which H. pylori infection causes the trans-differentiation of gastric cells to intestinal-type cells remains an important question. In the current study, we found that RUNX3 is deregulated in all human IM specimens examined by either down regulation or mislocalization; Aberrant localization of a gastric tumor suppressor RUNX3 is observed in most human cases of IM with concurrent H. pylori infection, and RUNX3 is down-regulated in most cases of IM without H. pylori-infection. The cytoplasmic mislocalization of a RUNX3 was associated with H. pylori-induced c-Src activation and RUNX tyrosine phosphorylation. Moreover, gastric epithelial cells of Runx3(-/-) mice expressed the intestinal markers Muc2 and Li-Cadherin, which suggests that the deregulation of Runx3 is a key event in the intestinalization of the gastric epithelium. Collectively, the results of the current study suggest that RUNX3 deregulation is associated with H. pylori-induced pathogenesis and the development of IM.

Aberrant expression of ß-catenin and its association with ΔNp63, Notch-1, and clinicopathological factors in oral squamous cell carcinoma.

The present study focuses on the correlation between the expression pattern of ß-catenin (component of Wnt signaling), ΔNp63 (proliferation marker), and Notch 1 (transmembrane receptor) in oral squamous cell carcinoma. The study also aims to investigate the interaction between ß-catenin and ΔNp63 in oral cancer. Furthermore, we also analyzed the prognostic significance of ß-catenin, ΔNp63, and Notch 1 in oral squamous cell carcinoma. Immunohistochemical analysis of ß-catenin, ΔNp63, and Notch 1 were done in 62 cases of oral squamous cell carcinoma. Co-immunoprecipitation analysis was done to study the possible interaction between ß-catenin and ΔNp63 in oral cancer. Kaplan-Meier method was used to estimate overall and disease-free survival, and the Log-rank test was used to compare the resulting curves. Statistically significant positive correlation was found between the localization of ß-catenin and the expression of ΔNp63 (p = 0.001**, r (s) = 0.427), whereas, no significant association was found between the expression pattern of ß-catenin and Notch 1. Interestingly, interaction between ß-catenin and ΔNp63 was observed in oral carcinoma. Moreover, ß-catenin and ΔNp63 may be related to worst survival in oral carcinoma. Statistically significant positive association between localization of ß-catenin and expression of ΔNp63 suggests that they might have dependent roles in maintaining the proliferation of oral carcinoma cells. In addition, the downregulated expression of Notch 1 was related to invasion and differentiation status of oral carcinoma cells. Furthermore, ß-catenin and ΔNp63 may be used as independent prognostic markers of oral carcinoma. On the other hand, interaction of ß-catenin with ΔNp63 may be a key event in maintaining the proliferation of oral carcinoma cells. The present study indicates that ß-catenin and ΔNp63 may be used as independent prognostic markers of oral carcinoma and the interaction of ß-catenin with ΔNp63 may be a crucial event in regulating proliferation and differentiation of oral carcinoma cells, which may be used as a target for therapeutic implications.