RNA-sequencing reveals differential fibroblast responses to bleomycin and pneumonectomy.

Pulmonary fibrosis is characterized by pathological accumulation of scar tissue in the lung parenchyma. Many of the processes that are implicated in fibrosis, including increased extracellular matrix synthesis, also occur following pneumonectomy (PNX), but PNX instead results in regenerative compensatory growth of the lung. As fibroblasts are the major cell type responsible for extracellular matrix production, we hypothesized that comparing fibroblast responses to PNX and bleomycin (BLM) would unveil key differences in the role they play during regenerative versus fibrotic lung responses. RNA-sequencing was performed on flow-sorted fibroblasts freshly isolated from mouse lungs 14 days after BLM, PNX, or sham controls. RNA-sequencing analysis revealed highly similar biological processes to be involved in fibroblast responses to both BLM and PNX, including TGF-ß1 and TNF-α. Interestingly, we observed smaller changes in gene expression after PNX than BLM at Day 14, suggesting that the fibroblast response to PNX may be muted by expression of transcripts that moderate pro-fibrotic pathways. Itpkc, encoding inositol triphosphate kinase C, was a gene uniquely up-regulated by PNX and not BLM. ITPKC overexpression in lung fibroblasts antagonized the pro-fibrotic effect of TGF-ß1. RNA-sequencing analysis has identified considerable overlap in transcriptional changes between fibroblasts following PNX and those overexpressing ITPKC.

ITPKC polymorphism (rs7251246 T > C), coronary artery aneurysms, and thrombosis in patients with Kawasaki disease in a Southern Han Chinese population.

Objectives: Kawasaki disease (KD) is a commonly acquired pediatric systemic vasculitis disease resulting in coronary artery aneurysm (CAA). The relationship between the ITPKC polymorphism (rs7251246) and the severity and susceptibility to KD in the Han Chinese population in Southern China remains unclear. Methods: We enrolled 262 children as controls and 221 children with KD (46 [20.8%] with intravenous immunoglobulin resistance and 82 [37.1%] with CAA). The relationship between the ITPKC rs7251246 polymorphism, KD susceptibility, and CAA formation was investigated. Results: While the ITPKC rs7251246 T>C polymorphism was not significantly associated with KD susceptibility, it was significantly related to the CAA risk in children with KD [CC/CT vs. TT: adjusted odds ratio [OR] 2.089, 95% confidence interval [CI] 1.085-4.020]. Male children with the rs7251246 CT/TT genotype had a significantly lower risk of thrombosis [CT/TT vs. CC: adjusted OR 0.251, 95% CI 0.068-0.923]. Children with KD, especially those with CAA, had significantly downregulated ITPKC mRNA compared to healthy children. ITPKC mRNA levels were lower in children with CAA who developed thrombosis (P=0.039). In children with KD, the CC genotype showed lower mRNA levels of ITPKC (P=0.035). Conclusion: The ITPKC rs7251246 T>C polymorphism may be a risk factor for CAA and thrombosis in children with KD in the Han Chinese population, likely due to differences in mature mRNA levels caused by interference of RNA splicing. Dual antiplatelet therapy for thrombosis is recommended for male children with the rs7251246 CC genotype.

Mercury increases IL-1ß and IL-18 secretion and intensifies coronary arteritis in an animal model of Kawasaki disease.

Kawasaki disease (KD) is a multisystem vasculitis that predominantly targets the coronary arteries in young children. Epidemiological data suggest both environmental and genetic factors contribute to the susceptibility and severity of the disease. Mercury (Hg) is a known environmental pollutant and a Ca2+ signaling modulator. Ca2+ signaling regulates the activation of NLRP3 inflammasome. Using the Lactobacillus casei cell wall extract (LCWE) induced coronary arteritis mouse model of KD; we studied the effect of mercury on inflammasome activation and its impact on the immunopathogenesis of KD. Mercury enhances the expression of inflammasome activation resulting in caspase-1 mediated secretion of IL-1ß and IL-18 cytokines. In vivo, the administration of mercury together with disease inducing LCWE exacerbates disease resulting in increased incidence and severity of coronary arteritis compared to LCWE alone. Mercury can act as a novel danger signal modulating Ca2+ signaling to increase IL-1ß and IL-18 secretion and intensifies coronary arteritis in an animal model of KD.

ITPKC as a Prognostic and Predictive Biomarker of Neoadjuvant Chemotherapy for Triple Negative Breast Cancer.

Triple negative breast cancer (TNBC) is the most aggressive subtype of breast cancer with higher mortality than the others. Pathological complete response (pCR) to neoadjuvant chemotherapy (NAC) is considered as a surrogate to predict survival. Inositol 1,4,5-trisphosphate 3-kinase C (ITPKC) is a negative regulator of T cell activation, and reduction in ITPKC function is known to promote Kawasaki disease. Given the role of tumor infiltrating lymphocytes in NAC and since TNBC has the most abundant immune cell infiltration in breast cancer, we hypothesized that the ITPKC expression level is associated with NAC response and prognosis in TNBC. The ITPKC gene was expressed in the mammary gland, but its expression was highest in breast cancer cells among other stromal cells in a bulk tumor. ITPKC expression was highest in TNBC, associated with its survival, and was its independent prognostic factor. Although high ITPKC was not associated with immune function nor with any immune cell fraction, low ITPKC significantly enriched cell proliferation-related gene sets in TNBC. TNBC with low ITPKC achieved a significantly higher pCR rate after NAC. To the best of our knowledge, this is the first report to demonstrate that ITPKC gene expression may be useful as a prognostic and predictive biomarker in TNBC.

Adjuvant herbal therapy for targeting susceptibility genes to Kawasaki disease: An overview of epidemiology, pathogenesis, diagnosis and pharmacological treatment of Kawasaki disease.

BACKGROUND: Kawasaki disease (KD) is a self-limiting acute systemic vasculitis occur mainly in infants and young children under 5 years old. Although the use of acetylsalicylic acid (AAS) in combination with intravenous immunoglobulin (IVIG) remains the standard therapy to KD, the etiology, genetic susceptibility genes and pathogenic factors of KD are still un-elucidated. PURPOSE: Current obstacles in the treatment of KD include the lack of standard clinical and genetic markers for early diagnosis, possible severe side effect of AAS (Reye's syndrome), and the refractory KD cases with resistance to IVIG therapy, therefore, this review has focused on introducing the current advances in the identification of genetic susceptibility genes, environmental factors, diagnostic markers and adjuvant pharmacological intervention for KD. RESULTS: With an overall update in the development of KD from different aspects, our current bioinformatics data has suggested CASP3, CD40 and TLR4 as the possible pathogenic factors or diagnostic markers of KD. Besides, a list of herbal medicines which may work as the adjunct therapy for KD via targeting different proposed molecular targets of KD have also been summarized. CONCLUSION: With the aid of modern pharmacological research and technology, it is anticipated that novel therapeutic remedies, especially active herbal chemicals targeting precise clinical markers of KD could be developed for accurate diagnosis and treatment of the disease.

Integrative genomic analysis for the functional roles of ITPKC in bone mineral density.

Osteoporosis is defined by low bone mineral density (BMD), which is mainly due to the imbalances in osteoclast and osteoblast activity. Previous studies indicated that early activation of osteoclasts relies on calcium entry through store-operated calcium (SOC) entry, and several genes, including STIM1, ORAI1, and ITPKC, are known as key regulators of SOC entry. However, the relationships between STIM1, ORAI1, ITPKC, and human BMD are still unclear. In order to investigate the plausible associations between these genes and BMD, we conducted a meta-analysis of genes expression and BMD using the publicly available GEO database. We further recruited 1044 subjects and tested associations between polymorphisms in these genes and BMD. Clinical information (including age, sex, and BMI) was collected and used for the analysis. Our results indicated that ITPKC gene expression was significantly associated with BMD. Furthermore, we found that one ITPKC SNP (rs2607420) was significantly associated with lumbar spine BMD. Through bioinformatics analysis, rs2607420 was found to be very likely to participate in the regulation of ITPKC expression. Our findings suggest that ITPKC is a susceptibility gene for BMD, and rs2607420 may play an important role in the regulation of this gene.

Regulation of Hematopoietic Cell Development and Function Through Phosphoinositides.

One of the most paramount receptor-induced signal transduction mechanisms in hematopoietic cells is production of the lipid second messenger phosphatidylinositol(3,4,5)trisphosphate (PIP3) by class I phosphoinositide 3 kinases (PI3K). Defective PIP3 signaling impairs almost every aspect of hematopoiesis, including T cell development and function. Limiting PIP3 signaling is particularly important, because excessive PIP3 function in lymphocytes can transform them and cause blood cancers. Here, we review the key functions of PIP3 and related phosphoinositides in hematopoietic cells, with a special focus on those mechanisms dampening PIP3 production, turnover, or function. Recent studies have shown that beyond "canonical" turnover by the PIP3 phosphatases and tumor suppressors phosphatase and tensin homolog (PTEN) and SH2 domain-containing inositol-5-phosphatase-1 (SHIP-1/2), PIP3 function in hematopoietic cells can also be dampened through antagonism with the soluble PIP3 analogs inositol(1,3,4,5)tetrakisphosphate (IP4) and inositol-heptakisphosphate (IP7). Other evidence suggests that IP4 can promote PIP3 function in thymocytes. Moreover, IP4 or the kinases producing it limit store-operated Ca2+ entry through Orai channels in B cells, T cells, and neutrophils to control cell survival and function. We discuss current models for how soluble inositol phosphates can have such diverse functions and can govern as distinct processes as hematopoietic stem cell homeostasis, neutrophil macrophage and NK cell function, and development and function of B cells and T cells. Finally, we will review the pathological consequences of dysregulated IP4 activity in immune cells and highlight contributions of impaired inositol phosphate functions in disorders such as Kawasaki disease, common variable immunodeficiency, or blood cancer.

ITPKC and SLC11A1 Gene Polymorphisms and Gene-Gene Interactions in Korean Patients with Kawasaki Disease.

PURPOSE: Kawasaki disease (KD) is an acute systemic vasculitis. Both the etiology of KD and the erythema of Bacille Calmette-Guérin (BCG) injection sites observed in the disease are poorly understood. We investigated the association between KD and single nucleotide polymorphisms (SNPs) in two candidate genes: inositol 1,4,5-triphosphate 3-kinase (ITPKC), a well-studied KD-associated gene, and solute carrier 11a1 (SLC11A1), which is associated with the hypersensitive reaction to the BCG strain in Koreans. MATERIALS AND METHODS: Associations between KD and SNPs in two genes were evaluated. Potential associations between BCG injection site erythema and SNPs in two genes were also evaluated. Gene-gene interactions between ITPKC and SLC11A1 in KD and BCG injection site erythema were also analyzed. RESULTS: Three tagging SNPs in ITPKC and five tagging SNPs in SLC11A1 were genotyped in 299 KD patients and 210 control children. SNP rs28493229 in ITPKC was associated with KD and coronary artery complications. SNP rs77624405 in SLC11A1 was associated with KD. Comparisons of KD patients with and without BCG injection site erythema revealed that SNP rs17235409 in SLC11A1 was associated with erythema; no erythema-associated SNPs in ITPKC were identified. Interactions between ITPKC rs28493229_GG and SLC11A1 rs17235409_GA and between ITPKC rs10420685_GG and SLC11A1 rs17235409_AA were strongly associated with BCG injection site erythema. CONCLUSION: This study identified several important polymorphisms in the ITPKC and SLC11A1 genes in Koreans. The genetic variants identified in this study affected KD and erythema of BCG injection sites independently and through gene-gene interactions. Also, the effects of the polymorphisms were age-dependent.

Potential association between ITPKC genetic variations and Hirschsprung disease.

Hirschsprung disease (HSCR) is a congenital and complex disorder characterized by intestinal obstruction due to the absence of enteric neurons along variable lengths of the hindgut. Our recent genome-wide association study (GWAS) has revealed regional associations with HSCR at several loci of inositol-trisphosphate 3-kinase C (ITPKC). For fine mapping, we additionally selected and genotyped a total of 12 single nucleotide polymorphisms (SNPs) of ITPKC in 187 HSCR patients and 283 unaffected controls, and performed a further combined imputation analysis based on genotype data from this second stage of fine mapping and our previous GWAS stage, totaling 902 subjects (187 HSCR cases and 715 controls). As a result, several SNPs (minimum P = 0.004) and a haplotype (P = 0.02) were found to be significantly associated with HSCR. In further in silico analyses to ascertain the potential functions of the significant variants, the change from the common allele to the rare allele of the highly conserved nonsynonymous rs76785336 showed a difference in mRNA folding structure. In the case of intronic SNPs, rs2607420 with a high consensus value was predicted to be a new splice site. Although this study has limitations (such as lack of functional evaluations, small number of cases, and further need of replication in other cohorts), our findings suggest that genetic variants of ITPKC may have a potential association with HSCR susceptibility and/or developmental diseases related to enteric nervous system development.

Specific expression and function of inositol 1,4,5-trisphosphate 3-kinase C (ITPKC) in wild type and knock-out mice.

Inositol 1,4,5-trisphosphate 3-kinase C (ITPKC) is the last identified member of the inositol 1,4,5-trisphosphate 3-kinases family which phosphorylates inositol 1,4,5-trisphosphate into inositol 1,3,4,5-tetrakisphosphate. Although expression and function of the two other family members ITPKA and ITPKB are rather well characterized, similar information is lacking for ITPKC. Here, we first defined the expression of Itpkc mRNA and protein in mouse tissues and cells using in situ hybridization and new antibodies. Surprisingly, we found that cells positive for ITPKC in the studied tissues express either a multicilium (tracheal and bronchial epithelia, brain ependymal cells), microvilli forming a brush border (small and large intestine, and kidney proximal tubule cells) or a flagellum (spermatozoa), suggesting a role for ITPKC either in the development or the function of these specialized cellular structures. Given this surprising expression, we then analyzed ITPKC function in multiciliated tracheal epithelial cells and sperm cells using our Itpkc knock-out mouse model. Unfortunately, no significant difference was observed between control and mutant mice for any of the parameters tested, leaving the exact in vivo function of this third Ins(1,4,5)P3 3-kinase still open.

Superantigen involvement and susceptibility factors in Kawasaki disease: profiles of TCR Vß2+ T cells and HLA-DRB1, TNF-α and ITPKC genes among Filipino patients.

Superantigens and genetic factors may play roles in the etiology and susceptibility to Kawasaki disease (KD). To investigate these roles, percentages of TCR-Vß2+ T cells were compared by flow cytometry using anti-Vß2 monoclonal antibodies and genotyping was done on HLA-DRB1 exon 2, the -308 site of the TNF-α promoter region, and ITPKC SNP rs28493229 by polymerase chain reaction followed by direct sequencing. There were higher percentages of Vß2+ T-cells in KD patients (9.5 ± 2.15%) compared to healthy controls (7.25 ± 1.48%) (P<0.05, Student's t-test, n=6-8/group). However, no polymorphisms were observed in exon 2 of HLA-DRB1 and in the -308 region of the TNF-α promoter. The ITPKC SNP rs28493229 G/C polymorphism was observed in 1 KD patient and 4 healthy controls. This study suggests that KD etiology may be associated with a superantigen and that HLA-DRB1 exon2, TNF-α -308 region and ITPKC SNP rs28493229 may not be associated with KD. This is the first study investigating Vß2+ T cells and candidate genes involvement among Filipino KD patients.