Mitochondrial Translocase TOMM22 Is Overexpressed in Pancreatic Cancer and Promotes Aggressive Growth by Modulating Mitochondrial Protein Import and Function.

Pancreatic cancer has the worst prognosis among all cancers, underscoring the need for improved management strategies. Dysregulated mitochondrial function is a common feature in several malignancies, including pancreatic cancer. Although mitochondria have their own genome, most mitochondrial proteins are nuclear-encoded and imported by a multi-subunit translocase of the outer mitochondrial membrane (TOMM). TOMM22 is the central receptor of the TOMM complex and plays a role in complex assembly. Pathobiologic roles of TOMM subunits remain largely unexplored. Here we report that TOMM22 protein/mRNA is overexpressed in pancreatic cancer and inversely correlated with disease outcomes. TOMM22 silencing decreased, while its forced overexpression promoted the growth and malignant potential of the pancreatic cancer cells. Increased import of several mitochondrial proteins, including those associated with mitochondrial respiration, was observed upon TOMM22 overexpression which was associated with increased RCI activity, NAD+/NADH ratio, oxygen consumption rate, membrane potential, and ATP production. Inhibition of RCI activity decreased ATP levels and suppressed pancreatic cancer cell growth and malignant behavior confirming that increased TOMM22 expression mediated the phenotypic changes via its modulation of mitochondrial protein import and functions. Altogether, these results suggest that TOMM22 overexpression plays a significant role in pancreatic cancer pathobiology by altering mitochondrial protein import and functions. IMPLICATIONS: TOMM22 bears potential for early diagnostic/prognostic biomarker development and therapeutic targeting for better management of patients with pancreatic cancer.

MYB exhibits racially disparate expression, clinicopathologic association, and predictive potential for biochemical recurrence in prostate cancer.

MYB acts as a potentiator of aggressiveness and castration resistance in prostate cancer (PCa) through aberrant activation of androgen receptor (AR) signaling. Since Black men experience higher PCa incidence and mortality than White men, we examined if MYB was differentially expressed in prostate tumors from patients of these racial backgrounds. The data reveal that aberrant MYB expression starts early in precancerous high-grade prostate intraepithelial neoplastic lesions and increases progressively in malignant cells. PCa tissues from Black patients exhibit higher MYB expression than White patients in overall and grade-wise comparisons. MYB also exhibits a positive correlation with AR expression and both display higher expression in advanced tumor stages. Notably, we find that MYB is a better predictor of biochemical recurrence than AR, pre-treatment PSA, or Gleason's grades. These findings establish MYB as a promising molecular target in PCa that could be used for improved risk prediction and therapeutic planning.

Assessment of multiple-opinion referrals and consults at the BC Children's Hospital Allergy Clinic.

BACKGROUND: Allergic disease is on the rise. Waitlists for specialists are long, and many referred patients have already received prior allergic assessment, either by a certified Allergist, Primary Care Provider, or other Specialist. It is important to understand the prevalence and motivating factors for multiple-opinion referrals, to deliver timely assessment for patients with allergic disease. METHODS: A retrospective chart review of demographic information, number of previous consultations, and motivation for new consults and multiple-opinion referrals, of pediatric patients aged 8 months-17 years to BC Children's Hospital Allergy Clinic from September 1, 2016-August 31, 2017, was performed. Referral data including reason for referral or multiple-opinion, primary allergic concerns, and others, from referral forms and consult notes were accessed through local Electronic Medical Records and subsequently analyzed for trends in categorical variables to assess the rationale for and impact of multiple-opinion referrals to our clinic. RESULTS: Of 1029 new referrals received, 210 (20.4%) were multiple-opinion referrals. Food allergy was the predominant allergic concern prompting further opinion (75.7%). The main rationale for seeking further opinions was wanting an assessment by a certified allergist in cases where prior consultation was performed by non-allergist specialist, primary care provider, or alternative health care provider. Of second-opinion referrals generated, 70 (33.3%) initial consultations were performed by an Allergist, whereas 140 (66.7%) were performed by a non-allergist. CONCLUSIONS: Many new consults at the BCCH Allergy Clinic are multiple-opinion assessments, contributing to long waitlists. Advocacy at the systems level through standardized referral guidelines, centralized triaging systems, and stronger support for Primary Care Providers is needed to provide better access in Canada for children needing a specialized Allergist. Trial registration UBC/BCCH Research Ethics Board.

MYB interacts with androgen receptor, sustains its ligand-independent activation and promotes castration resistance in prostate cancer.

BACKGROUND: Aberrant activation of androgen receptor signalling following castration therapy is a common clinical observation in prostate cancer (PCa). Earlier, we demonstrated the role of MYB overexpression in androgen-depletion resistance and PCa aggressiveness. Here, we investigated MYB-androgen receptor (AR) crosstalk and its functional significance. METHODS: Interaction and co-localization of MYB and AR were examined by co-immunoprecipitation and immunofluorescence analyses, respectively. Protein levels were measured by immunoblot analysis and enzyme-linked immunosorbent assay. The role of MYB in ligand-independent AR transcriptional activity and combinatorial gene regulation was studied by promoter-reporter and chromatin immunoprecipitation assays. The functional significance of MYB in castration resistance was determined using an orthotopic mouse model. RESULTS: MYB and AR interact and co-localize in the PCa cells. MYB-overexpressing PCa cells retain AR in the nucleus even when cultured under androgen-deprived conditions. AR transcriptional activity is also sustained in MYB-overexpressing cells in the absence of androgens. MYB binds and promotes AR occupancy to the KLK3 promoter. MYB-overexpressing PCa cells exhibit greater tumorigenicity when implanted orthotopically and quickly regain growth following castration leading to shorter mice survival, compared to those carrying low-MYB-expressing prostate tumours. CONCLUSIONS: Our findings reveal a novel MYB-AR crosstalk in PCa and establish its role in castration resistance.

Inborn errors of immunity manifesting as atopic disorders.

Inborn errors of immunity are traditionally best known for enhancing susceptibility to infections. However, allergic inflammation, among other types of immune dysregulation, occurs frequently in patients with inborn errors of immunity. As such, the term primary atopic disorders (PADs) was recently coined to describe the group of heritable monogenic allergic disorders. It is becoming increasingly important for clinicians to recognize that allergic diseases such as food allergy, atopic dermatitis, and allergic asthma are expressions of misdirected immunity, and in patients who present with severe, early-onset, or coexisting allergic conditions, these can be indications of an underlying PAD. Identifying monogenic allergic disease through next-generation sequencing can dramatically improve outcomes by allowing the use of precision-based therapy targeting the patient's underlying molecular defect. It is therefore imperative that clinicians recognize PADs to be able to provide informed therapeutic options and improve patient outcomes. Here, we summarize the clinical features commonly seen with each of the currently known PADs, identify clinical warning signs that warrant assessment for PADs, and lastly, discuss the benefits of timely diagnosis and management of these conditions.

Clinicopathologic significance and race-specific prognostic association of MYB overexpression in ovarian cancer.

Late diagnosis, unreliable prognostic assessment, and poorly-guided therapeutic planning result in dismal survival of ovarian cancer (OC) patients. Therefore, identifying novel functional biomarker(s) is highly desired for improved clinical management. MYB is an oncogenic transcription factor with emerging functional significance in OC. Here we examined its clinicopathologic significance by immunohistochemistry and TCGA/GTex data analyses. Aberrant MYB expression was detected in 94% of OC cases (n = 373), but not in the normal ovarian tissues (n = 23). MYB was overexpressed in all major epithelial OC histological subtypes exhibiting the highest incidence (~ 97%) and overall expression in serous and mucinous carcinomas. MYB expression correlated positively with tumor grades and stages. Moreover, MYB exhibited race-specific prognostic association. Moderate-to-high MYB levels were significantly associated with both poor overall- (p = 0.02) and progression-free (p = 0.02) survival in African American (AA), but not in the Caucasian American (CA) patients. Consistent with immunohistochemistry data, we observed significantly higher MYB transcripts in OC cases (n = 426) than normal ovary (n = 88). MYB transcripts were significantly higher in all epithelial OC subtypes, compared to normal, and its greater levels predicted poor survival in AA OC, but not CA OC, patients. Thus, MYB appears to be a useful clinical biomarker for prognostication, especially in AA patients.

Clinical IRAK4 deficiency caused by homozygosity for the novel IRAK4 (c.1049delG, p.Gly350Glufs*15) variant.

The innate immune system allows for rapid recognition of pathogens. Toll-like receptor (TLR) signaling is a key aspect of the innate immune response, and interleukin-1 receptor-associated kinase 4 (IRAK4) plays a vital role in the TLR signaling cascade. Each TLR recognizes a distinct set of pathogen-associated molecular patterns (PAMPs) that encompass conserved microbial components such as lipopolysaccharides and flagellin. Upon binding of PAMPs and TLR activation, TLR intracellular domains initiate the oligomerization of the myeloid differentiation primary response 88 (MyD88), IRAK1, IRAK2, and IRAK4 signaling platform known as the Myddosome complex while also triggering the Toll/IL-1R domain-containing adaptor-inducing IFN-ß (TRIF)-dependent pathway. The Myddosome complex initiates signal transduction pathways enabling the activation of NF-κB and mitogen-activated protein kinase (MAPK) transcription factors and the subsequent production of inflammatory cytokines. Human IRAK4 deficiency is an autosomal recessive inborn error of immunity that classically presents with blunted or delayed inflammatory response to infection and susceptibility to a narrow spectrum of pyogenic bacteria, particularly Streptococcus pneumoniae, Staphylococcus aureus, and Pseudomonas aeruginosa. We describe a case of IRAK4 deficiency in an 11-mo-old boy with concurrent S. pneumoniae bacteremia and S. aureus cervical lymphadenitis with a blunted inflammatory response to invasive infection. Although initial clinical immune profiling was unremarkable, a high degree of suspicion for an innate immune defect prompted genetic sequencing. Genetic testing revealed a novel variant in the IRAK4 gene (c.1049delG, p.(Gly350Glufs*15)) predicted to be likely pathogenic. Functional testing showed a loss of IRAK4 protein expression and abolished TLR signaling, confirming the pathogenicity of this novel IRAK4 variant.

Co-targeting of CXCR4 and hedgehog pathways disrupts tumor-stromal crosstalk and improves chemotherapeutic efficacy in pancreatic cancer.

Pancreatic cancer (PC) remains a therapeutic challenge because of its intrinsic and extrinsic chemoresistance mechanisms. Here, we report that C-X-C motif chemokine receptor 4 (CXCR4) and hedgehog pathways cooperate in PC chemoresistance via bidirectional tumor-stromal crosstalk. We show that when PC cells are co-cultured with pancreatic stellate cells (PSCs) they are significantly more resistant to gemcitabine toxicity than those grown in monoculture. We also demonstrate that this co-culture-induced chemoresistance is abrogated by inhibition of the CXCR4 and hedgehog pathways. Similarly, the co-culture-induced altered expression of genes in PC cells associated with gemcitabine metabolism, antioxidant defense, and cancer stemness is also reversed upon CXCR4 and hedgehog inhibition. We have confirmed the functional impact of these genetic alterations by measuring gemcitabine metabolites, reactive oxygen species production, and sphere formation in vehicle- or gemcitabine-treated monocultures and co-cultured PC cells. Treatment of orthotopic pancreatic tumor-bearing mice with gemcitabine alone or in combination with a CXCR4 antagonist (AMD3100) or hedgehog inhibitor (GDC-0449) displays reduced tumor growth. Notably, we show that the triple combination treatment is the most effective, resulting in nearly complete suppression of tumor growth. Immunohistochemical analysis of Ki67 and cleaved caspase-3 confirm these findings from in vivo imaging and tumor measurements. Our findings provide preclinical and mechanistic evidence that a combination of gemcitabine treatment with targeted inhibition of both the CXCR4 and hedgehog pathways improves outcomes in a PC mouse model.

Looking at cancer health disparities without the colored lenses.

Cancer health disparities (CHDs), defined as the adverse differences in cancer incidence and mortality, are prevalent in certain racial and ethnic groups. Underlying causes of CHDs are multi-factorial and debatable. While low socioeconomic status, geographical location, lifestyle and behavioral factors are mostly believed to contribute to CHDs, regardless of ethnic and racial background, significant data now also exist to support a genetic basis of such disparities as well. Clearly, CHDs could best be understood by studying the interplay of multiple (genetic and non-genetic) factors and then translating the resulting knowledge into effective approaches for reducing the existing disparity gaps. This review article highlights these aspects in brief and calls the people of different expertise to work together to make an impact and tackle the challenges associated with CHDs.

Gemcitabine treatment promotes immunosuppressive microenvironment in pancreatic tumors by supporting the infiltration, growth, and polarization of macrophages.

Chemotherapy-induced immunosuppression poses an additional challenge to its limited efficacy in pancreatic cancer (PC). Here we investigated the effect of gemcitabine on macrophages, which are the first line of immune-defense mechanisms. We observed an increased presence of macrophages in orthotopic human pancreatic tumor xenografts from mice treated with gemcitabine as compared to those from vehicle only-treated mice. Conditioned media from gemcitabine-treated PC cells (Gem-CM) promoted growth, migration and invasion of RAW264.7 macrophage. In addition, Gem-CM also induced upregulation of M2-polarized macrophage markers, arginase-1 and TGF-ß1. Cytokine profiling of gemcitabine-treated PC cells identified IL-8 as the most differentially-expressed cytokine. Incubation of Gem-CM with IL-8 neutralizing antibody diminished its ability to induce growth, migration and invasion of RAW264.7 macrophages, but did not abrogate their M2 polarization. Together, our findings identify IL-8 as an important mediator in the gemcitabine-induced infiltration of macrophages within the pancreatic tumor microenvironment and suggest the requirement of additional mechanism(s) for macrophage polarization.

The effect of the physical consistency of the diet on the bone quality of the mandibular condyle in rats.

OBJECTIVE: This study aimed to analyze how the physical consistency of the diet affects the bone quality at the mandibular condyle. DESIGN: Sixty-three Wistar rats were randomly assigned to three groups. Twenty-two animals composed each group and they were fed with either a liquid, soft or hard diet. Seven animals were sacrificed from each group at days 7, 20, and 40 respectively. Their mandibles were removed and scanned at the postero-superior area of the condyle with a micro-CT scan. RESULTS: showed a statistically significant difference for the bone mineral density (p<0.01) and total mineral density (p<0.01), when comparing the hard against the liquid group after seven days. After 20days both, the soft and the liquid diet groups, computed a statistically significant difference demonstrating a significant decrease in the measured values for bone mineral density, bone mineral content, total mineral density, and total mineral content. At day 40, the values stayed lower for the soft and liquid diets, even though they did not reach a significant difference. CONCLUSIONS: This study supports the idea that a soft or liquid diet has a negative impact on the bone quality of the mandible, particularly during the periods of more active growing.

Glucose Metabolism Reprogrammed by Overexpression of IKKε Promotes Pancreatic Tumor Growth.

Aberrant expression of the kinase IKKε in pancreatic ductal adenocarcinoma (PDAC) has been associated with poor prognosis. In this study, we define a pathobiologic function for IKKε in reprogramming glucose metabolism and driving progression in PDAC. Silencing IKKε in PDAC cells, which overexpressed it endogenously, was sufficient to reduce malignant cell growth, clonogenic potential, glucose consumption, lactate secretion, and expression of genes involved in glucose metabolism, without impacting the basal oxygen consumption rate. IKKε silencing also attenuated c-Myc in a manner associated with diminished signaling through an AKT/GSK3ß/c-MYC phosphorylation cascade that promoted MYC nuclear accumulation. In an orthotopic mouse model, IKKε-silenced PDAC exhibited a relative reduction in glucose uptake, tumorigenicity, and metastasis. Overall, our findings offer a preclinical mechanistic rationale to target IKKε to improve the therapeutic management of PDAC in patients. Cancer Res; 76(24); 7254-64. ©2016 AACR.

YTH StreetConnect: Development and Usability of a Mobile App for Homeless and Unstably Housed Youth.

BACKGROUND: Homeless and unstably housed (H/UH) youth are disproportionately affected by sexual health issues, including human immunodeficiency virus/sexually transmitted diseases, teen pregnancy, and dating violence, and are at a higher risk for poor mental health and underutilization of services. Research suggests that linking health care to H/UH adolescents might help improve their continuity of care, with most preferring to access health care information via the Internet. YTH StreetConnect is a dual-purpose mobile app that helps H/UH youth access health and vital services in Santa Clara County, CA, USA. We developed YTH StreetConnect PRO in parallel with the youth app as a companion tablet app for providers who serve H/UH youth. OBJECTIVE: The objective of our study was to develop a mobile app to support H/UH youth and their providers in accessing health and vital resources, and to conduct usability and feasibility testing of the app among H/UH youth and technical consultants with local expertise in serving H/UH youth. METHODS: Formative research included a literature review on H/UH youths' mobile phone and Internet usage. In January 2015, we conducted interviews with medical and service providers of H/UH youth. Usability and feasibility testing were done with target audiences. Additionally, we conducted focus groups with youth regarding the app's youth friendliness, accessibility, and usefulness. RESULTS: H/UH youth and their providers noted the app's functionality, youth friendliness, and resources. Usability testing proposed improvements to the app, including visual updates to the user interface, map icons, new underrepresented resource categories, and the addition of a peer rating system. Limitations included a small sample size among H/UH youth and providers and a single site for the study (Santa Clara County, CA), making the findings ungeneralizable to the US population. CONCLUSIONS: YTH StreetConnect is a promising way to increase service utilization, provide referral access, and share resources among H/UH youth and providers. Input from H/UH youth and providers offers insights on how to improve future models of YTH StreetConnect and similar programs that assist H/UH youth.

Mammary-type fibroepithelial neoplasms of the vulva: a case report and review of the literature.

Mammary-type fibroepithelial neoplasms of the vulva are rare lesions of uncertain histogenesis. Origin from ectopic breast tissue and from anogenital glandular tissue that shares similar histologic homology with breast tissue has been postulated. We report the case of a 45-year-old woman who presented with a vulvar mass of several years duration. Excision of the lesion and subsequent histologic examination showed a mammary-type fibroadenoma with apocrine change. No ectopic breast tissue was identified outside the lesion. The theories of histogenesis of these neoplasms and additional cases of mammary-type lesions of the vulva reported in the medical literature are reviewed.