Variations in ncRNA gene LOC284889 and MIF-794CATT repeats are associated with malaria susceptibility in Indian populations

Survival-Associated Cellular Response Maintained in Pancreatic Ductal Adenocarcinoma (PDAC) Switched Between Soft and Stiff 3D Microgel Culture

Pancreatic ductal adenocarcinoma (PDAC) accounts for about 90% of all pancreatic cancer cases. Five-year survival rates have remained below 12% since the 1970s, in part due to the difficulty in detection prior to metastasis (migration and invasion into neighboring organs and glands). Mechanical memory is a concept that has emerged over the past decade that may provide a path toward understanding how invading PDAC cells "remember" the mechanical properties of their diseased ("stiff", elastic modulus, E ≈ 10 kPa) microenvironment even while invading a healthy ("soft", E ≈ 1 kPa) microenvironment. Here, we investigated the role of mechanical priming by culturing a dilute suspension of PDAC (FG) cells within a 3D, rheologically tunable microgel platform from hydrogels with tunable mechanical properties. We conducted a suite of acute (short-term) priming studies where we cultured PDAC cells in either a soft (E ≈ 1 kPa) or stiff (E ≈ 10 kPa) environment for 6 h, then removed and placed them into a new soft or stiff 3D environment for another 18 h. Following these steps, we conducted RNA-seq analyses to quantify gene expression. Initial priming in the 3D culture showed persistent gene expression for the duration of the study, regardless of the subsequent environments (stiff or soft). Stiff 3D culture was associated with the downregulation of tumor suppressors (LATS1, BCAR3, CDKN2C), as well as the upregulation of cancer-associated genes (RAC3). Immunofluorescence staining (BCAR3, RAC3) further supported the persistence of this cellular response, with BCAR3 upregulated in soft culture and RAC3 upregulated in stiff-primed culture. Stiff-primed genes were stratified against patient data found in The Cancer Genome Atlas (TCGA). Upregulated genes in stiff-primed 3D culture were associated with decreased survival in patient data, suggesting a link between patient survival and mechanical priming.

Association of MIF gene polymorphisms with pemphigus vulgaris: a case-control study with comprehensive review of the literature

BACKGROUND

Functional macrophage migration inhibitory factor (MIF) gene polymorphisms are associated with elevated serum levels of MIF and increased susceptibility to various autoimmune diseases. MIF levels in the sera of pemphigus vulgaris (PV) patients are increased; however, no definite association has been demonstrated between PV and MIF gene polymorphisms. The present study was conducted to ascertain any association between MIF-173*G-C and MIF-794*CATT_5-8 polymorphisms and PV.

METHODS

Seventy-five patients with PV and 252 healthy, unrelated, voluntary controls were enrolled randomly in the study. MIF-173*G-C polymorphism (rs755622) was genotyped using polymerase chain reaction (PCR) followed by restriction fragment length analysis, and MIF-794*CATT_5-8 (rs5844572) was genotyped using PCR followed by capillary gel electrophoresis. Subsequently, the allelic, genotype, and haplotype frequencies were determined and compared for both groups. Data were also analyzed with respect to sex, age at onset, type of disease, and duration of disease.

RESULTS

No significant association was observed in terms of allelic, genotype, and haplotype frequencies of MIF gene polymorphisms in PV patients. However, a significantly lower prevalence of the C allele (P=0.02) and CATT₇ allele (P=0.03) was seen in our patient population compared to healthy controls. Analysis of the effect of various factors such as gender, age at onset, type of disease, and disease duration revealed no significant association with the genetic variants.

CONCLUSIONS

MIF-173*G-C and -794*CATT_5-8 polymorphisms are not associated with PV.

Single-nucleotide polymorphism and haplotype analysis of macrophage migration inhibitory factor gene and its correlation with serum macrophage migration inhibitory factor levels in North Indian psoriatic patients with moderate disease severity: A cross-sectional study

BACKGROUND

Psoriasis is associated with significant morbidity and impaired quality of life. Identification of the host genes that influence disease susceptibility and can potentially guide future, targeted therapy is the need of the hour.

AIMS

The aim of the study was to investigate the associations of macrophage migration inhibitory factor (MIF) gene polymorphisms, that is, a 5-8-CATT tetra nucleotide repeats at -794 (-794*CATT5-8) and a single-nucleotide polymorphism at -173 (-173*G/C) with the risk of chronic plaque psoriasis and to observe the correlation, if any, of disease determinants with genetic functional variants and circulating MIF levels.

METHODS

Five hundred and seventeen individuals (265 psoriasis patients and 252 controls) were genotyped for MIF gene polymorphisms. Data were analyzed with respect to disease susceptibility, serum MIF levels, disease severity, age at onset, disease duration and presence of comorbidities.

RESULTS

The presence of co-morbidities was more frequently noted in patients with late onset disease (P = 0.01). No statistically significant differences were observed either in genotype (P = 0.680) or allele frequency (P = 0.69) with respect to distribution of MIF-173*G/C polymorphism between patients and controls. The frequencies of genotypes -794*CATT 5/7 and 7/7 were significantly lower in patients (P = 0.027* and 0.038*, respectively). CATT*5/MIF-173*C haplotype occurred at a higher frequency in patients (odds ratio 3.03, 95% confidence intervals 1.09-8.47, P = 0.02). The mean serum MIF levels were significantly higher in patients as compared to controls (P < 0.001). The presence of either extended MIF -794*CATT repeats or C allele did not reveal any significant association with serum MIF levels or age at onset. Analysis of effect of various disease determinants revealed no significant association with genetic variants and serum MIF levels.

LIMITATIONS

The lesional expression of MIF could not be studied.

CONCLUSION

Our results showed that CATT*5/MIF-173*C haplotype is associated with increased susceptibility to psoriasis vulgaris.

Role of Host and Parasite MIF Cytokines during Leishmania Infection

Macrophage migration inhibitory factor (MIF) is an immunoregulatory cytokine that has been extensively characterized in human disease and in mouse models. Its pro-inflammatory functions in mammals includes the retention of tissue macrophages and a unique ability to counteract the immunosuppressive activity of glucocorticoids. MIF also acts as a survival factor by preventing activation-induced apoptosis and by promoting sustained expression of inflammatory factors such as TNF-α and nitric oxide. The pro-inflammatory activity of MIF has been shown to be protective against Leishmania major infection in mouse models of cutaneous disease, however the precise role of this cytokine in human infections is less clear. Moreover, various species of Leishmania produce their own MIF orthologs, and there is evidence that these may drive an inflammatory environment that is detrimental to the host response. Herein the immune response to Leishmania in mouse models and humans will be reviewed, and the properties and activities of mammalian and Leishmania MIF will be integrated into the current understandings in this field. Furthermore, the prospect of targeting Leishmania MIF for therapeutic purposes will be discussed.

Variations in macrophage migration inhibitory factor gene are not associated with visceral leishmaniasis in India

BACKGROUND

The host genetic factors play important role in determining the outcome of visceral leishmaniasis (VL). Macrophage migration inhibitory factor (MIF) is an important host cytokine, which is a key regulator of innate immune system. Genetic variants in MIF gene have been found to be associated with several inflammatory and infectious diseases. Role of MIF is well documented in leishmaniasis diseases, including Indian visceral leishmaniasis, where elevated level of serum MIF has been associated with VL phenotypes. However, there was no genetic study to correlate MIF variants in VL, therefore, we aimed to study the possible association of three reported MIF gene variants -794 CATT, -173G > C and non-coding RNA gene LOC284889 in Indian VL phenotype.

METHODS

Study subjects comprised of 214 VL patients along with ethnically and demographically matched 220 controls from VL endemic regions of Bihar state in India.

RESULTS

We found no significant difference between cases and controls in allelic, genotypic and haplotype frequency of the markers analysed [-794 CATT repeats (χ2=0.86; p=0.35; OR=0.85; 95% CI=0.61-1.19); -173 G>C polymorphism (χ2=1.11; p=0.29; OR=0.83; 95% CI=0.59-1.16); and LOC284889 (χ2=0.78; p=0.37; OR=0.86; 95% CI=0.61-1.20)].

CONCLUSION

Since we did not find any significant differences between case and control groups, we conclude that sequencing of complete MIF gene and extensive study on innate and adaptive immunity genes may help in identifying genetic variations that are associated with VL susceptibility/resistance among Indians.

A polymorphism in the haptoglobin, haptoglobin related protein locus is associated with risk of human sleeping sickness within Cameroonian populations

Background

Human African Trypanosomiasis (HAT) is a neglected disease targeted for elimination as a public health problem by 2020. Elimination requires a better understanding of the epidemiology and clinical evolution of HAT. In addition to the classical clinical evolution of HAT, asymptomatic carriers and spontaneous cure have been reported in West Africa. A genetic component to human susceptibility to HAT has been suggested to explain these newly observed responses to infection. In order to test for genetic associations with infection response, genetic polymorphism in 17 genes were tested (APOL1, IL1B, IL4, IL4R, IL6, IL8, IL12B, IL12RB1, IL10, TNFA, INFG, MIF, HLA-G, HLA-A, HP, HPR and CFH).

Methodology

A case-control study was performed on 180 blood samples collected from 56 cases and 124 controls from Cameroon. DNA was extracted from blood samples. After quality control, 25 samples (24 controls and 1 case) were eliminated. The genotyping undertaken on 155 individuals including 55 cases and 100 controls were investigated at 96 loci (88 SNPs and 8 indels) located on 17 genes. Associations between these loci and HAT were estimated via a case-control association test.

Results

Analyses of 64 SNPs and 4 indels out of 96 identified in the selected genes reveal that the minor allele (T) of rs8062041 in haptoglobin (HP) appeared to be protective against HAT (p = 0.0002395, OR 0.359 (CI₉₅ [0.204–0.6319])); indicating higher frequency in cases compared to controls. This minor allele with adjusted p value of 0.0163 is associated with a lower risk (protective effect) of developing sleeping sickness.

Conclusion

The haptoglobin related protein HPR and HP are tightly linked and both are duplicated in some people and may lead to higher activity. This increased production could be responsible of the protection associated with rs8062041 even though this SNP is within HP.

Human African trypanosomiasis (HAT) or sleeping sickness is a neglected tropical disease targeted for elimination by 2020. This elimination requires a better understanding of the epidemiology and clinical evolution of this disease. Beside the classical clinical evolution, asymptomatic carriers, seropositive and spontaneous cure of infected persons have been reported in West Africa. Arguments in favor of human genetic susceptibility to HAT have been raised to explain this variability in clinical presentation. This study investigated the genetic polymorphism of 17 genes between controls and sleeping sickness patients in Southern Cameroon in order to improve our knowledge of human susceptibility to trypanosome infections. We identified single nucleotide polymorphisms and indels in 17 selected genes involved in immune responses and carried out a case-control candidate gene association study and demonstrated differences between variants associated with the disease. From these genes, only haptoglobin (HP) at the SNP rs8062041 was found to have polymorphisms which were strongly associated with trypanosomiasis. The minor allele (T) at this SNP position appeared to be protective against HAT (p = 0.0002395, OR 0.359 (CI₉₅ [0.204–0.6319])) reducing the risk of developing disease approximately threefold. The haptoglobin related protein (HPR) is adjacent to HP and is a component of the Trypanolytic factor that kills trypanosomes. The HP and HPR locus is duplicated in some people. The rs8062041 variant may be associated with this duplication and it is possible that increased production of HPR is the cause of the protection associated with rs8062041. The results reported here will contribute to the knowledge of the role of human genetics in disease progression, and thus lead to the identification of novel biomarkers which could involve development of new diagnostics, treatments and intervention strategies.

Impact of MIF Gene Promoter Variations on Risk of Rheumatic Heart Disease and Its Age of Onset in Saudi Arabian Patients

Although macrophage migration inhibitory factor (MIF) has consistently been shown to be an important immune modulator, data on the association between MIF promoter variations and the risk of developing rheumatic heart disease (RHD) remain inconclusive. RHD is an important complication of streptococcal infections in the Middle East, not least in Saudi Arabia, and identifying risk markers is an important priority. Therefore, we investigated the association between two functional MIF promoter variations and RHD susceptibility and severity in Saudi patients: the MIF-173G > C substitution (rs755622) and the MIF-794 CATT5-8 tetranucleotide repeat (rs5844572). Three hundred twenty-six individuals (124 RHD patients and 202 age-, sex-, and ethnically matched healthy controls) were genotyped using allelic discrimination and fragment analysis. Data were analyzed with respect to disease susceptibility, severity, sex, and age of onset. There was a significantly lower frequency of 173C allele carriage in RHD patients compared to controls [odds ratio (OR) = 0.47; 95% confidence intervals (CIs) = 0.28-0.77; p = 0.003]. Interestingly, the 173C allele was associated with late disease onset (p = 0.001). The 794 5-repeat allele was associated with decreased RHD risk (OR = 0.56; 95% CIs = 0.38-0.82; p = 0.003). In contrast, the 794 6-repeat allele was associated with increased risk of RHD (OR = 1.7; 95% CIs = 1.2-2.5; p = 0.002). MIF promoter variations appear to have a dual role in RHD, with 173C allele non-carriers at higher risk of developing RHD at a younger age. These results require further validation in larger multi-ethnic cohorts, and functional studies are necessary to understand the underlying molecular mechanisms driving the at-risk phenotype.

Basic biology and therapeutic implications of lncRNA

Long non-coding RNAs (lncRNA), a class of non-coding RNA molecules recently identified largely due to the efforts of FANTOM, and later GENCODE and ENCODE consortia, have been a subject of intense investigation in the past decade. Extensive efforts to get deeper understanding of lncRNA biology have yielded evidence of their diverse structural and regulatory roles in protecting chromosome integrity, maintaining genomic architecture, X chromosome inactivation, imprinting, transcription, translation and epigenetic regulation. Here we will briefly review the recent studies in the field of lncRNA biology focusing mostly on mammalian species and discuss their therapeutic implications.