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BackgroundThere are very few studies and cases in the literature describing metastatic breast cancer in the male population, accounting for less than 1% of all cases. Of those who have been reported, the vast majority fail to survive beyond 5 years from time of diagnosis. The lack of literature in this population makes it difficult for clinicians to foresee and prepare for upcoming complications in management. One of the more serious complications in managing metastatic breast cancer is the development of pseudocirrhosis, a frequent long-term side effect of chemotherapy and/or radiation typically seen in patients with malignancy in the liver.Case PresentationWe report the case of a 48-year-old male with a completely unremarkable family, medical, and social history other than a homozygous mutation in his MTHFR gene who was diagnosed with stage IV ER/PR-positive, HER-2/neu negative, BRCA1 and BRCA2-negative breast cancer with metastasis to bone, lung, and liver who was successfully treated with a regimen consisting of radiation, Denosumab, Leuprorelin, and Anastrozole. 8 years later since initiation of treatments, he continues to survive and undergo symptomatic management of long-term side-effects of his treatments.ConclusionsTo our knowledge this is the only reported case of metastatic breast cancer with pseudocirrhosis in a male patient. It is imperative to report this unique case to help increase awareness for clinicians managing other males with breast cancer. What makes this case even more reportable is the good outcome overall as our patient remains alive and well 8 years since time of diagnosis, a relatively difficult and rare feat to achieve in end-stage breast cancer.

Background Currently, the management of SARS-CoV-2 varies with no definitive clinical guidelines, as scientific evidence across the globe differs in therapeutic options. This study intended to provide some clarity to the insufficient data based on the role of monotherapy with tocilizumab (TCZ) and combination therapy with remdesivir (RDV) and TCZ among patients with SARS-CoV-2 infection in El Paso, Texas. We evaluated the use of each therapy in the presence of steroids as the standard of care. Methods One hundred and fifty-four SARS-CoV-2-infected patients from four different medical centers in El Paso, Texas, were screened, with 113 eligible for this longitudinal comparative observational study (February 1, 2020 to October 31, 2020). Group 1 (80 patients) received TCZ in the first 24 hours following admission, then methylprednisolone for the next 72 hours and group 2 (33 patients) were given TCZ as detailed in the single therapy group, plus RDV within the first 24 hours. Mann Whitney U test assessed median differences in laboratory biomarkers and Bivariate Logistic Regression assessed the odds of risk. An observation is considered statistically significant when P-value is ≤0.05. Results Patients in group 1 had a statistically significant lower odds for ventilation use than group 2 (OR=0.34, 95%CI=0.12-0.95, p=0.034), although no statistically significant difference in mortality outcomes was observed across groups (OR=0.43, 95%CI:0.13-1.39, p=0.269). Conclusions We concluded that the use of TCZ in SARS-CoV-2-infected patients in El Paso, with or without RDV, reported no mortality benefit. However, some minimal/non-use of ventilation benefit was observed in group 1. Nonetheless, a randomized controlled trial study is recommended to ultimately determine the combination role of TCZ and RDV among this highly vulnerable group of patients.

Coughing is a primary symptomatic pathway of respiratory or air-borne disease transmission, including COVID-19. Several parameters such as cougher's age, gender, and posture affect particle dispersion indoors. This study numerically investigates the transient cough evolution, contamination range, particle reach probability, and deposition fraction for different age groups of males and females in standing and sitting postures in a ventilated room. The efficacy of a cloth mask has also been studied with and without the influence of air ventilation. Validated Computational Fluid Dynamics methodology has been implemented to model complex physics such as turbulent buoyant cloud, particle-air interaction, particle collision/breakup, and droplet evaporation. Our results show that overall, the contamination range is slightly lower for females due to lower cough velocities and particle counts. Moreover, a significant fraction of particles crosses the two meters social distancing guideline threshold with an unhindered cough. Besides, wearing a cloth mask reduces the average contamination range by approximately two-third of the distance compared to coughing without the mask. However, aerosolized particles reach longer streamwise distances and drift for extended durations beyond thirty seconds. This study can be used to improve the heating, ventilation, and air conditioning recommendations and distancing guidelines in indoor settings.

Coccidioidomycosis is a fungal infection caused by Coccidioides immitis which thrives in dry desert climates such as the southwestern United States. Disseminated coccidioidomycosis is often seen in patients with an underlying immunodeficiency. Historically there have been few reported cases of opportunistic infections in the setting of low CD4+ count and no evidence of HIV infection. Coccidioidomycosis typically presents asymptomatically or as a minor respiratory illness in immunocompetent individuals. We report a case of disseminated coccidioidomycosis in a patient who is otherwise immunocompetent. Patient is a 24-year-old Hispanic male who presented with severe headache, fever, body pain, vomiting, and diarrhea for approximately 14 days. On admission, patient’s CD4+ count was 91 and CSF culture grew Coccidioides immitis, for which patient was started on fluconazole. Patient’s hospital stay was complicated by multiple bouts of altered mental status, fevers, hyponatremia, hydrocephalus, neurogenic bladder, new-onset Mobitz II heart arrhythmia, urinary tract infection, and sepsis. MRI studies revealed abnormal enhancement of leptomeninges, bilateral basal ganglia, thecal sac and cauda equina fibers, signifying disseminated disease. Patient’s serum Coccidioides complement fixation (IgG) titers remained elevated despite aggressive therapy with IV amphotericin B. After a total of six months of hospitalization, including treatment with intrathecal amphotericin B, patient’s last CD4+ count was 549, CSF IgG titers achieved

Objective Insulin regulates both glucose uptake and postnatal cardiac growth. The anabolic effects of insulin are mediated by the mammalian target of rapamycin (mTOR), an evolutionarily conserved kinase which is also a convergence point between nutrient sensing and cell growth. We postulated that mTOR signalling in the heart requires the metabolism of glucose. Methods We interrogated the insulin-mediated mTOR signalling pathway in response to different metabolic interventions regulating substrate metabolism in the isolated working rat heart and in isolated cardiomyocytes. Results Although insulin enhanced Akt activity, phosphorylation of mTOR and its downstream targets (p70S6K and 4EBP1) required the addition of glucose. Glucose-dependent p70S6K phosphorylation was independent of the hexosamine biosynthetic pathway, the AMP kinase pathway, and the pentose phosphate pathway. However, inhibition of glycolysis downstream of hexokinase markedly enhanced p70S6K phosphorylation. Furthermore, 2-deoxyglucose activated p70S6K suggesting that phosphorylation of glucose is required for carbohydrate-mediated mTOR signalling in the heart. Lastly, we also found enhanced p70S6K phosphorylation in the hearts of diabetic rats. Conclusion Phosphorylation of glucose is necessary for insulin-dependent mTOR activity in the heart, suggesting a link between intermediary metabolism and cardiac growth.

Glycogen synthase kinase (GSK) 3beta is a negative regulator of stress-induced cardiomyocyte hypertrophy. It is not clear, however, if GSK-3beta plays any role in regulating normal cardiac growth and cardiac function. Herein we report that a transgenic mouse expressing wild type GSK-3beta in the heart has a dramatic impairment of normal post-natal cardiomyocyte growth as well as markedly abnormal cardiac contractile function. The most striking phenotype, however, is grossly impaired diastolic relaxation, which leads to increased filling pressures of the left ventricle and massive atrial enlargement. This is due to profoundly abnormal calcium handling, leading to an inability to normalize cytosolic [Ca2+] in diastole. The alterations in calcium handling are due at least in part to direct down-regulation of the sarcoplasmic reticulum calcium ATPase (SERCA2a) by GSK-3beta, acting at the level of the SERCA2 promoter. These studies identify GSK-3beta as a regulator of normal growth of the heart and are the first of which we are aware, to demonstrate regulation of expression of SERCA2a, a critical determinant of diastolic function, by a cytosolic signaling pathway, the activity of which is dynamically modulated. De-regulation of GSK-3beta leads to severe systolic and diastolic dysfunction and progressive heart failure. Because down-regulation of SERCA2a plays a central role in the diastolic and systolic dysfunction of patients with heart failure, these findings have potential implications for the therapy of this disorder.

β-Catenin is a transcriptional activator that regulates embryonic development as part of the Wnt pathway and also plays a role in tumorigenesis. The mechanisms leading to Wnt-induced stabilization of β-catenin, which results in its translocation to the nucleus and activation of transcription, have been an area of intense interest. However, it is not clear whether stimuli other than Wnts can lead to important stabilization of β-catenin and, if so, what factors mediate that stabilization and what biologic processes might be regulated. Herein we report that β-catenin is stabilized in cardiomyocytes after these cells have been exposed to hypertrophic stimuli in culture or in vivo . The mechanism by which β-catenin is stabilized is distinctly different from that used by Wnt signaling. Although, as with Wnt signaling, inhibition of glycogen synthase kinase-3 remains central to hypertrophic stimulus-induced stabilization of β-catenin, the mechanism by which this occurs involves the recruitment of activated PKB to the β-catenin-degradation complex. PKB stabilizes the complex and phosphorylates glycogen synthase kinase-3 within the complex, inhibiting its activity directed at β-catenin. Finally, we demonstrate via adenoviral gene transfer that β-catenin is both sufficient to induce growth in cardiomyocytes in culture and in vivo and necessary for hypertrophic stimulus-induced growth. Thus, in these terminally differentiated cells, β-catenin is stabilized by hypertrophic stimuli acting via heterotrimeric G protein-coupled receptors. The stabilization occurs via a unique Wnt-independent mechanism and results in cellular growth.

Multiple intracellular signaling pathways have been shown to regulate the hypertrophic growth of cardiomyocytes. Both necessary and sufficient roles have been described for the mitogen activated protein kinase(1) (MAPK) signaling pathway, specific protein kinase C (PKC) isoforms, and calcineurin. Here we investigate the interdependence between calcineurin, MAPK, and PKC isoforms in regulating cardiomyocyte hypertrophy using three separate approaches. Hearts from hypertrophic calcineurin transgenic mice were characterized for PKC and MAPK activation. Transgenic hearts demonstrated activation of c-Jun NH(2)-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK1/2), but not p38 MAPK factors. Calcineurin transgenic hearts demonstrated increased activation of PKCalpha, beta(1), and theta, but not of epsilon, beta(2), or lambda. In a second approach, cultured cardiomyocytes were infected with a calcineurin adenovirus to induce hypertrophy and the effects of pharmacologic inhibitors or co-infection with a dominant negative adenovirus were examined. Calcineurin-mediated hypertrophy was prevented with PKC inhibitors, Ca(2+) chelation, and attenuated with a dominant negative SEK-1 (MKK4) adenovirus, but inhibitors of ERK or p38 activation had no effect. In a third approach, we examined the activation of MAPK factors and PKC isoforms during the progression of load-induced hypertrophy in aortic banded rats with or without cyclosporine. We determined that inhibition of calcineurin activity with cyclosporine prevented PKCalpha, theta, and JNK activation, but did not affect PKCepsilon, beta, lambda, ERK1/2, or p38 activation. Collectively, these data indicate that calcineurin hypertrophic signaling is interconnected with PKCalpha, theta, and JNK in the heart, while PKCepsilon, beta, lambda, p38, and ERK1/2 are not involved in calcineurin-mediated hypertrophy.

In cells capable of entering the cell cycle, including cancer cells, beta-catenin has been termed a master switch, driving proliferation over differentiation. However, its role as a transcriptional activator in terminally differentiated cells is relatively unknown. Herein we utilize conditional, cardiac-specific deletion of the beta-catenin gene and cardiac-specific expression of a dominant inhibitory mutant of Lef-1 (Lef-1Delta20), one of the members of the T-cell factor/lymphocyte enhancer factor (Tcf/Lef) family of transcription factors that functions as a coactivator with beta-catenin, to demonstrate that beta-catenin/Tcf/Lef-dependent gene expression regulates both physiologic and pathological growth (hypertrophy) of the heart. Indeed, the profound nature of the growth impairment of the heart in the Lef-1Delta20 mouse, which leads to very early development of heart failure and premature death, suggests beta-catenin/Tcf/Lef targets are dominant regulators of cardiomyocyte growth. Thus, our studies, employing complementary models in vivo, implicate beta-catenin/Tcf/Lef signaling as an essential growth-regulatory pathway in terminally differentiated cells.

Female gender and estrogen-replacement therapy in postmenopausal women are associated with improved heart failure survival, and physiological replacement of 17β-estradiol (E2) reduces infarct size and cardiomyocyte apoptosis in animal models of myocardial infarction (MI). Here, we characterize the molecular mechanisms of E2 effects on cardiomyocyte survival in vivo and in vitro. Ovariectomized female mice were treated with placebo or physiological E2 replacement, followed by coronary artery ligation (placebo-MI or E2-MI) or sham operation (sham) and hearts were harvested 6, 24, and 72 hours later. After MI, E2 replacement significantly increased activation of the prosurvival kinase, Akt, and decreased cardiomyocyte apoptosis assessed by terminal deoxynucleotidyltransferase dUTP nick-end labeling (TUNEL) staining and caspase 3 activation. In vitro, E2 at 1 or 10 nmol/L caused a rapid 2.7-fold increase in Akt phosphorylation and a decrease in apoptosis as measured by TUNEL staining, caspase 3 activation, and DNA laddering in cultured neonatal rat cardiomyocytes. The E2-mediated reduction in apoptosis was reversed by an estrogen receptor (ER) antagonist, ICI 182,780, and by phospho-inositide-3 kinase inhibitors, LY294002 and Wortmannin. Overexpression of a dominant negative-Akt construct also blocked E2-mediated reduction in cardiomyocyte apoptosis. These data show that E2 reduces cardiomyocyte apoptosis in vivo and in vitro by ER- and phospho-inositide-3 kinase–Akt–dependent pathways and support the relevance of these pathways in the observed estrogen-mediated reduction in myocardial injury.

Generation of arachidonic acid by the ubiquitously expressed cytosolic phospholipase A2 (PLA2) has a fundamental role in the regulation of cellular homeostasis, inflammation and tumorigenesis. Here we report that cytosolic PLA2 is a negative regulator of growth, specifically of striated muscle. We find that normal growth of skeletal muscle, as well as normal and pathologic stress-induced hypertrophic growth of the heart, are exaggerated in Pla2g4a-/- mice, which lack the gene encoding cytosolic PLA2. The mechanism underlying this phenotype is that cytosolic PLA2 negatively regulates insulin-like growth factor (IGF)-1 signaling. Absence of cytosolic PLA2 leads to sustained activation of the IGF-1 pathway, which results from the failure of 3-phosphoinositide-dependent protein kinase (PDK)-1 to recruit and phosphorylate protein kinase C (PKC)-zeta, a negative regulator of IGF-1 signaling. Arachidonic acid restores activation of PKC-zeta, correcting the exaggerated IGF-1 signaling. These results indicate that cytosolic PLA2 and arachidonic acid regulate striated muscle growth by modulating multiple growth-regulatory pathways.

Renal ischemia/reperfusion and ATP depletion/repletion in LLC-PK 1 cells result in phosphorylation of FKHR and FKHRL1. Background Cell death and survival pathways are critical determinants of epithelial cell fate after ischemia. Forkhead proteins have been implicated in the regulation of cellular survival. Methods and Results We have found that none of the forkhead family of proteins, FKHR, is phosphorylated after ischemia/reperfusion in the rat kidney. The time course of phosphorylation is similar to the time course of activation of the forkhead protein kinase Akt/protein kinase B (PKB), with maximal phosphorylation at 24 to 48 hours postreperfusion when the process of regeneration peaks. Extracellular signal-regulated kinase (ERK)1/2 activation has also been implicated as prosurvival in the injured kidney. ERK1/2 were phosphorylated in postischemic kidneys at 5, 30, and 90 minutes of reperfusion, with phosphorylation decreased by 24 and 48 hours. Immunocytochemical analysis revealed increased phospho-ERK1/2 in the thick ascending limb and isolated cells of the S3 segment, which have lost apical actin staining. To understand the relationship between forkhead phosphorylation, Akt, and ERK1/2, an in vitro model of injury was employed. After 40 minutes of chemical anoxia followed by dextrose addition for 20 minutes to replete adenosine triphosphate (ATP) levels, FKHR and FKHRL1 are phosphorylated. The levels of phospho-Akt are increased for at least 120 minutes after dextrose addition with a maximum at 20 minutes. Phosphorylation of Akt, FKHR, and FKHRL1 are phosphatidylinositol 3-kinase (PI 3-kinase) dependent since phosphorylation is reduced by the PI 3-kinase inhibitors, wortmannin, or LY294002. Inhibition of mitogen-activated protein kinase (MAPK)/ERK kinase (MEK1/2), the upstream activator of ERK1/2, has no effect on forkhead protein phosphorylation after chemical anoxia/dextrose addition. Conclusion We conclude that PI 3-kinase and Akt are activated after renal ischemia/reperfusion and that Akt phosphorylation leads to phosphorylation of FKHR and FKHRL1, which may affect epithelial cell fate in acute renal failure.

Background —Left ventricular failure is commonly preceded by a period of hypertrophy. Intriguingly, many of the signaling pathways that have been implicated in the regulation of hypertrophy, including the 3 mitogen-activated protein kinases (MAPKs: extracellular signal-regulated kinase, stress-activated protein kinase, and p38), protein phosphatase, calcineurin, and the protein kinase Akt and its target glycogen synthase kinase-3 (GSK-3), also regulate the apoptotic response. Methods and Results —To understand the mechanisms that might regulate the progression of heart failure, we analyzed the activity of these signaling pathways in the hearts of patients with advanced heart failure, patients with compensated cardiac hypertrophy, and normal subjects. In patients with hypertrophy, neither the MAPK nor the Akt/GSK-3 pathways were activated, and the dominant signaling pathway was calcineurin. In failing hearts, calcineurin activity was increased but less so than in the hypertrophied hearts, and all 3 MAPKs and Akt were activated (and, accordingly, GSK-3β was inhibited), irrespective of whether the underlying diagnosis was ischemic or idiopathic cardiomyopathy. Conclusions —In the failing heart, there is a clear prohypertrophic activity profile, likely occurring in response to increased systolic wall stress and neurohormonal mediators. However, with the activation of these hypertrophic pathways, potent proapoptotic and antiapoptotic signals may also be generated. Therapies directed at altering the balance of activity of these signaling pathways could potentially alter the progression of heart failure.

Hypertrophy is a basic cellular response to a variety of stressors and growth factors, and has been best characterized in myocytes. Pathologic hypertrophy of cardiac myocytes leads to heart failure, a major cause of death and disability in the developed world. Several cytosolic signaling pathways have been identified that transduce prohypertrophic signals, but to date, little work has focused on signaling pathways that might negatively regulate hypertrophy. Herein, we report that glycogen synthase kinase-3beta (GSK-3beta), a protein kinase previously implicated in processes as diverse as development and tumorigenesis, is inactivated by hypertrophic stimuli via a phosphoinositide 3-kinase-dependent protein kinase that phosphorylates GSK-3beta on ser 9. Using adenovirus-mediated gene transfer of GSK-3beta containing a ser 9 to alanine mutation, which prevents inactivation by hypertrophic stimuli, we demonstrate that inactivation of GSK-3beta is required for cardiomyocytes to undergo hypertrophy. Furthermore, our data suggest that GSK-3beta regulates the hypertrophic response, at least in part, by modulating the nuclear/cytoplasmic partitioning of a member of the nuclear factor of activated T cells family of transcription factors. The identification of GSK-3beta as a transducer of antihypertrophic signals suggests that novel therapeutic strategies to treat hypertrophic diseases of the heart could be designed that target components of the GSK-3 pathway.

Nat. Med. 9, 944–951 (2003) In the version of this article initially published online, the last sentence of the 'Isolation of Plag4a−/− and wild-type glomerular mesangial cells' section of the Methods contained an error. Both instances of 'μm' should read 'μM'. We regret the error.

Cardiac hypertrophy often presages the development of heart failure. Numerous cytosolic signaling pathways have been implicated in the hypertrophic response in cardiomyocytes in culture, but their roles in the hypertrophic response to physiologically relevant stimuli in vivo is unclear. We previously reported that adenovirus-mediated gene transfer of SEK-1(KR), a dominant inhibitory mutant of the immediate upstream activator of the stress-activated protein kinases (SAPKs), abrogates the hypertrophic response of neonatal rat cardiomyocytes to endothelin-1 in culture. We now report that gene transfer of SEK-1(KR) to the adult rat heart blocks SAPK activation by pressure overload, demonstrating that the activity of cytosolic signaling pathways can be inhibited by gene transfer of loss-of-function mutants in vivo. Furthermore, gene transfer of SEK-1(KR) inhibited pressure overload–induced cardiac hypertrophy, as determined by echocardiography and several postmortem measures including left ventricular (LV) wall thickness, the ratio of LV weight to body weight, cardiomyocyte diameter, and inhibition of atrial natriuretic factor expression. Our data suggest that the SAPKs are critical regulators of cardiac hypertrophy in vivo, and therefore may serve as novel drug targets in the treatment of hypertrophy and heart failure. J. Clin. Invest. 104:391–398 (1999).

Since 1993, when Sadoshima et al1 published their observations on the role of Angiotensin II (Ang II) in the stretch-induced hypertrophic response of cardiomyocytes, we have known that peptide hormones were important in the development of hypertrophy stimulated by cell stretch, the initiating stimulus in pressure overload-induced hypertrophy and in the hypertrophy that occurs in the noninfarcted myocardium following a myocardial infarction. Ang II, as well as endothelin-1 (ET-1) and α-adrenergic agents, activate intracellular pathways by binding to 7 transmembrane-spanning receptors coupled to heterotrimeric G proteins of the Gq class. The critical role of this class of receptors and G proteins in pressure overload-induced hypertrophy was elegantly demonstrated by Ahkter et al2 who showed that cardiac specific expression in mice of a peptide that blocked signal transmission by Gq markedly blunted the hypertrophic response to aortic banding. See p 509 The question that has dominated the field of cardiomyocyte biology is how do these hormones, acting via their cognate receptors and Gq, trigger the hypertrophic response? One clear conclusion has evolved thus far: the hypertrophic response of cardiomyocytes is regulated by an enormously complex network of interacting cytosolic signaling pathways.3 Gq activation ultimately results in the production of intermediates that increase cytosolic free [Ca2+] and activate members of the protein kinase C family, and leads to the recruitment of several protein kinases, including the mitogen-activated protein kinases (MAPKs), calcium calmodulin-dependent protein kinases, Akt/PKB, and the Janus kinases. These kinases phosphorylate a number of transcription factors, increasing their transcriptional activating activity and, in some cases, DNA binding activity. Elevated [Ca2+] can also activate the protein phosphatase, calcineurin,4 which dephosphorylates members of the nuclear factor-activated T cell (NF-AT) family of transcription factors, causing their nuclear translocation. Activated transcription factors bind to specific DNA sequences …

Wnt signaling pathways are some of the most intensely studies in all of biology. Recently, a number of classical heterotrimeric G protein coupled receptors (GPCRs) have been shown to activate the canonical Wnt pathway, culminating in the stabilization of beta-catenin and induction of transcription of genes regulated by the Tcf/Lef family of transactivators. However, mechanisms by which these GPCRs accomplish this differ in key ways, and in some circumstances, the phenotypes produced are novel. Herein, we will examine mechanisms by which classical GPCRs interact with the canonical Wnt pathway, culminating in its activation, and describe the consequences of this activation, focusing on the heart. In the heart, the contractile cells, or cardiomyocytes, are terminally differentiated and virtually exclusively grow by increasing cell size (hypertrophy) rather than cell number, and we will describe how GPCR-mediated activation of the canonical pathway can drive this process.