Prolactin-inducible protein (PIP) is a multifunctional glycoprotein that is highly expressed and found in the secretions of apocrine glands such as salivary, lacrimal, and sweat glands including the ...mammary glands. PIP has been implicated in various diseases, including breast cancer, gross cystic disease of the breast, keratoconus of the eye, and the autoimmune Sjögren’s syndrome. Here we have generated a Pip knockout (KO) mouse using the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRSPR-associated (Cas)9 system. The Cas9 protein and two single guide RNAs targeting specific regions for both exons 1 and 2 of the Pip gene were microinjected into mouse embryos. The deletions and insertions promoted by CRISPR/Cas9 system on the Pip gene successfully disrupted Pip protein coding, as confirmed by PCR genotyping, sequencing, and ultimately Western blot analysis. This mouse model was generated in the inbred C57Bl/6J mouse, which exhibits lower genetic variation. This novel CRISPR Pip KO mouse model will not only be useful for future studies to interrogate the multifunctional role of PIP in physiological processes but will facilitate a broader understanding of the function of PIP in vivo while providing unprecedented insight into its role in a spectrum of diseases attributed to the deregulation of the PIP gene.
Claudin 1 in Breast Cancer: New Insights Zhou, Bowen; Moodie, Amanda; Blanchard, Anne A A ...
Journal of clinical medicine,
11/2015, Letnik:
4, Številka:
12
Journal Article
Recenzirano
Odprti dostop
Claudin 1 is a small transmembrane protein responsible for maintaining the barrier function that exists between epithelial cells. A tight junction protein that regulates the paracellular transport of ...small ions across adjacent cells, claudin 1 maintains cellular polarity and plays a major role in cell-cell communication and epithelial cell homeostasis. Long considered to be a putative tumor suppressor in human breast cancer, new studies suggest a role much more complex. While most invasive breast cancers exhibit a down regulation or absence of claudin 1, some aggressive subtypes that exhibit high claudin 1 levels have now been described. Furthermore, a causal role for claudin 1 in breast cancer progression has recently been demonstrated in some breast cancer cell lines. In this review we highlight new insights into the role of claudin 1 in breast cancer, including its involvement in collective migration and epithelial mesenchymal transition (EMT).
Gitelman syndrome (GS) is a rare, salt-losing tubulopathy characterized by hypokalemic metabolic alkalosis with hypomagnesemia and hypocalciuria. The disease is recessively inherited, caused by ...inactivating mutations in the SLC12A3 gene that encodes the thiazide-sensitive sodium-chloride cotransporter (NCC). GS is usually detected during adolescence or adulthood, either fortuitously or in association with mild or nonspecific symptoms or both. The disease is characterized by high phenotypic variability and a significant reduction in the quality of life, and it may be associated with severe manifestations. GS is usually managed by a liberal salt intake together with oral magnesium and potassium supplements. A general problem in rare diseases is the lack of high quality evidence to inform diagnosis, prognosis, and management. We report here on the current state of knowledge related to the diagnostic evaluation, follow-up, management, and treatment of GS; identify knowledge gaps; and propose a research agenda to substantiate a number of issues related to GS. This expert consensus statement aims to establish an initial framework to enable clinical auditing and thus improve quality control of care.
The claudin 1 tight junction protein, solely responsible for the barrier function of epithelial cells, is frequently down regulated in invasive human breast cancer. The underlying mechanism is ...largely unknown, and no obvious mutations in the claudin 1 gene (CLDN1) have been identified to date in breast cancer. Since many genes have been shown to undergo deregulation through splicing and mis-splicing events in cancer, the current study was undertaken to investigate the occurrence of transcript variants for CLDN1 in human invasive breast cancer.
RT-PCR analysis of CLDN1 transcripts was conducted on RNA isolated from 12 human invasive breast tumors. The PCR products from each tumor were resolved by agarose gel electrophoresis, cloned and sequenced. Genomic DNA was also isolated from each of the 12 tumors and amplified using PCR CLDN1 specific primers. Sanger sequencing and single nucleotide polymorphism (SNP) analyses were conducted.
A number of CLDN1 transcript variants were identified in these breast tumors. All variants were shorter than the classical CLDN1 transcript. Sequence analysis of the PCR products revealed several splice variants, primarily in exon 1 of CLDN1; resulting in truncated proteins. One variant, V1, resulted in a premature stop codon and thus likely led to nonsense mediated decay. Interestingly, another transcript variant, V2, was not detected in normal breast tissue samples. Further, sequence analysis of the tumor genomic DNA revealed SNPs in 3 of the 4 coding exons, including a rare missense SNP (rs140846629) in exon 2 which represents an Ala124Thr substitution. To our knowledge this is the first report of CLDN1 transcript variants in human invasive breast cancer. These studies suggest that alternate splicing may also be a mechanism by which claudin 1 is down regulated at both the mRNA and protein levels in invasive breast cancer and may provide novel insights into how CLDN1 is reduced or silenced in human breast cancer.
Aim
To compare transanal irrigation with conservative bowel management for the treatment of bowel dysfunction in Spina bifida (SB) patients.
Methods
Patients with SB and bowel dysfunction were ...randomly assigned to receive either transanal irrigation or conservative bowel management. The effectiveness of the treatment was defined as a decrease of 4 points in the neurogenic bowel dysfunction (NBD) score at week 10. Data on incontinence (Cleveland scores; Jorge‐Wexner JW) and constipation (Knowles‐Eccersley‐Scott Symptom Constipation Score KESS) were recorded at 10 and 24 weeks after inclusion. Data were analysed on an intention‐to‐treat basis.
Results
A total of 34 patients were randomised: 16 patients to conservative bowel management and 18 patients to transanal irrigation. A total of 19/31 (61%) patients improved at week 10, 13 (76%) in the transanal irrigation group versus six (43%) in the conservative group (p = 0.056). In the irrigation group, the decrease in NBD score was −6.9 (−9.9 to −4.02) versus −1.9 (−6.5 to −2.8) in the conservative group (p = 0.049 in univariate and p = 0.004 in multivariate analysis). The NBD, Cleveland (JW and KESS) and Rosenberg scores were significantly lower in the transanal irrigation group than in the conservative bowel management group at week 10.
Conclusions
This prospective, randomised, controlled, multicentre study in adult patients with SB suggests that transanal irrigation may be more effective than conservative bowel management.
Defects in tight junctions, gate-keepers of the integrity of the epidermal barrier function, are known to contribute to cancer development. As such, enhancing our understanding of how the expression ...of proteins involved in these junctions is regulated in cancer, remains a priority. Although the expression of one of these proteins, claudin 1, is down regulated in most invasive human breast cancers (HBC), we have recently shown that high levels of claudin 1, characterized tumors belonging to the very aggressive basal-like breast cancer (BLBC) subtype. In these tumors, the claudin 1 protein, usually localized in the cell membrane, is often mislocalized to the cytoplasm.
To examine the clinical relevance of this observation, we have generated and analyzed an invasive HBC tissue microarray consisting of 151 breast tumor samples; 79 of which presented a basal-like phenotype (i.e. ER-ve, PR-ve HER2-ve, CK5/6 or EGFR+ve). We also interrogated the outcome of claudin 1 knockdown in a human BLBC cell line, BT-20.
Immunohistochemical analysis of this patient cohort revealed a significant association between high claudin 1 expression and BLBCs in women 55 years of age and older. Interestingly, no significant association was found between claudin 1 and nodal involvement, tumor grade or tumor size. Regression analysis however, showed a significant positive association between claudin 1 and claudin 4, even though claudin 4 did not significantly correlate with patient age. Claudin 1 knockdown in BT-20 cells resulted in decreased cell migration. It also significantly altered the expression of several genes involved in epithelial-mesenchymal-transition (EMT); in particular, SERPINE 1 (PAI1) and SSP1 (osteopontin), known to inhibit EMT and cancer cell migration. Conversely, genes known to maintain EMT through their interaction, SNAIL2, TCF4 and FOXC2 were significantly down regulated.
The association of high claudin 1 protein levels observed in tumors derived from older women with BLBC, suggests that claudin 1 has the potential to serve as a marker which can identify a specific subgroup of patients within the BLBC subtype and thus, further contribute to the characterization of these ill-defined breast cancers. More importantly, our studies strongly suggest that claudin 1 directly participates in promoting breast cancer progression, possibly through the alteration of expression of EMT genes.
Mutations in the
gene, located on the X chromosome, have been recently detected in males with a transient form of antenatal Bartter syndrome or with idiopathic polyhydramnios. The aim of this study ...is to analyze the proportion of the population with mutations in this gene in a French cohort of patients with antenatal Bartter syndrome.
The French cohort of patients with antenatal Bartter syndrome encompasses 171 families. Mutations in genes responsible for types 1-4 have been detected in 75% of cases. In patients without identified genetic cause (
=42), transient antenatal Bartter syndrome was reported in 12 cases. We analyzed the
gene in the entire cohort of negative cases by Sanger sequencing and retrospectively collected clinical data regarding pregnancy as well as the postnatal outcome for positive cases.
We detected mutations in
in 17 patients, including the 12 with transient antenatal Bartter syndrome, from 16 families. Fifteen different mutations were detected (one whole deletion, three frameshift, three splicing, three nonsense, two inframe deletions, and three missense); 13 of these mutations had not been previously described. Interestingly, two patients are females; in one of these patients our data are consistent with selective inactivation of chromosome X explaining the severity. The phenotypic presentation in our patients was variable and less severe than that of the originally described cases.
mutations explained 9% of cases of antenatal Bartter syndrome in a French cohort, and accounted for 38% of patients without other characterized mutations and for 44% of male probands of negative cases. Our study confirmed previously published data and showed that females can be affected. As a result, this gene must be included in the screening of the most severe clinical form of Bartter syndrome.
Background:
Persistent physical symptoms are common after a coronavirus disease 2019 (COVID-19) episode, but their pathophysiological mechanisms remain poorly understood. In this study, we aimed to ...explore the association between anxiety and depression at 1-month after acute infection and the presence of fatigue, dyspnea, and pain complaints at 3-month follow-up.
Methods:
We conducted a prospective study in patients previously hospitalized for COVID-19 followed up for 3 months. The Hospital Anxiety and Depression Scale (HAD-S) was administered by physicians at 1-month follow-up, and the presence of fatigue, dyspnea, and pain complaints was assessed at both 1 month and 3 months. Multivariable logistic regressions explored the association between anxiety and depression subscores and the persistence of each of the physical symptom at 3 months.
Results:
A total of 84 patients were included in this study (Median age: 60 years, interquartile range: 50.5–67.5 years, 23 women). We did not find any significant interaction between anxiety and the presence of fatigue, dyspnea, or pain complaints at 1 month in predicting the persistence of these symptoms at 3 months (all
p
≥ 0.36). In contrast, depression significantly interacted with the presence of pain at 1 month in predicting the persistence of pain at 3 months (OR: 1.60, 95% CI: 1.02–2.51,
p
= 0.039), with a similar trend for dyspnea (OR: 1.51, 95% CI: 0.99–2.28,
p
= 0.052).
Discussion and Conclusion:
Contrary to anxiety, depression after an acute COVID-19 episode may be associated with and increased risk of some persistent physical symptoms, including pain and dyspnea.
Patients with Gitelman syndrome (GS), an inherited salt-losing tubulopathy, are usually treated with potassium-sparing diuretics or nonsteroidal anti-inflammatory drugs and oral potassium and ...magnesium supplementations. However, evidence supporting these treatment options is limited to case series studies. We designed an open-label, randomized, crossover study with blind end point evaluation to compare the efficacy and safety of 6-week treatments with one time daily 75 mg slow-release indomethacin, 150 mg eplerenone, or 20 mg amiloride added to constant potassium and magnesium supplementation in 30 patients with GS (individual participation: 48 weeks). Baseline plasma potassium concentration was 2.8±0.4 mmol/L and increased by 0.38 mmol/L (95% confidence interval 95% CI, 0.23 to 0.53; P<0.001) with indomethacin, 0.15 mmol/L (95% CI, 0.02 to 0.29; P=0.03) with eplerenone, and 0.19 mmol/L (95% CI, 0.05 to 0.33; P<0.01) with amiloride. Fifteen patients became normokalemic: six with indomethacin, three with eplerenone, and six with amiloride. Indomethacin significantly reduced eGFR and plasma renin concentration. Eplerenone and amiloride each increased plasma aldosterone by 3-fold and renin concentration slightly but did not significantly change eGFR. BP did not significantly change. Eight patients discontinued treatment early because of gastrointestinal intolerance to indomethacin (six patients) and hypotension with eplerenone (two patients). In conclusion, each drug increases plasma potassium concentration in patients with GS. Indomethacin was the most effective but can cause gastrointestinal intolerance and decreased eGFR. Amiloride and eplerenone have similar but lower efficacies and increase sodium depletion. The benefit/risk ratio of each drug should be carefully evaluated for each patient.
The prolactin-inducible protein (PIP) is considered a valuable biomarker that is associated with both benign and malignant pathological conditions of the mammary gland. The function of PIP in breast ...tumorigenesis remains unknown; however, evidence from our laboratory and others suggest that it regulates host immunity. Studies with PIP-deficient (PIP
−/−
) mice demonstrated significantly lower numbers of CD4
+
T cells in their secondary lymphoid organs, impaired Th1 response, and impaired nitric oxide (NO) production. To further delineate the immunoregulatory role of PIP, we compared the expression of IFN-γR and TLR4, pro-inflammatory cytokine production, and intracellular signaling events by IFN-γ and lipopolysaccharide (LPS)-stimulated macrophages from wild-type (WT) and PIP
−/−
mice. We showed that although the expressions of IFN-γR and TLR4 were comparable, productions of pro-inflammatory cytokines were decreased in PIP
−/−
macrophages. This was associated with decreased phosphorylation of mitogen-activated protein kinase (MAPK) and signal transducer of activation of transcription (STAT) proteins in macrophages from PIP
−/−
mice. Interestingly, the expression of suppressors of cytokine signaling (SOCS) 1 and 3 proteins, known to suppress IFN-γ and LPS signaling, was higher in PIP
−/−
macrophages compared to those from WT mice. Collectively, our studies show that deficiency of PIP significantly affects intracellular signaling events leading to decreased pro-inflammatory cytokine production, and further confirms a role for PIP as an important immunoregulatory protein. This direct link between PIP and cell-mediated immunity, a key component of the immune system that is critical for cancer control, may have significant therapeutic implications.
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