Advances in Social Media Research:Past, Present and Future

Social media comprises communication websites that facilitate relationship forming between users from diverse backgrounds, resulting in a rich social structure. User generated content encourages inquiry and decision-making. Given the relevance of social media to various stakeholders, it has received significant attention from researchers of various fields, including information systems. There exists no comprehensive review that integrates and synthesises the findings of literature on social media. This study discusses the findings of 132 papers (in selected IS journals) on social media and social networking published between 1997 and 2017. Most papers reviewed here examine the behavioural side of social media, investigate the aspect of reviews and recommendations, and study its integration for organizational purposes. Furthermore, many studies have investigated the viability of online communities/social media as a marketing medium, while others have explored various aspects of social media, including the risks associated with its use, the value that it creates, and the negative stigma attached to it within workplaces. The use of social media for information sharing during critical events as well as for seeking and/or rendering help has also been investigated in prior research. Other contexts include political and public administration, and the comparison between traditional and social media. Overall, our study identifies multiple emergent themes in the existing corpus, thereby furthering our understanding of advances in social media research. The integrated view of the extant literature that our study presents can help avoid duplication by future researchers, whilst offering fruitful lines of enquiry to help shape research for this emerging field

ERG expression is an independent prognostic factor and allows refined risk stratification in cytogenetically normal acute myeloid leukemia: A comprehensive analysis of ERG, MN1, and BAALC transcript levels using oligonucleotide microarrays.

Purpose: Recently, several novel molecular prognostic markers were identified in cytogenetically normal acute myeloid leukemia (CN-AML). In addition to the well-known influence of FLT3, NPM1, and CEBPA mutations, high transcript levels of the ERG, BAALC, and MN1 genes have been associated with inferior outcomes, but the relative importance of these risk markers remains to be defined. - Patients and Methods: We analyzed ERG, BAALC, and MN1 expression levels in a cohort of 210 patients with CN-AML who received intensive chemotherapy. Expression levels of ERG, BAALC, and MN1 were determined in bone marrow samples by using oligonucleotide microarrays. - Results: High transcript levels of ERG, BAALC, and MN1 were predictors for inferior overall survival (OS) and a lower rate of complete remissions (CRs). There were significant positive correlations between the expression levels of all three genes. ERG expression levels predicted OS in elderly patients (ie, age 60 years or older) with CN-AML (P = .006) as well as in younger patients (P = .013). In multivariate analyses, high ERG expression was independently associated with a lower CR rate (P = .013), shorter event-free survival (P = .008), and shorter OS (P = .005). Patients who had low ERG levels and absent FLT3 internal tandem duplication (ITD) had a 5-year OS of 44%, and patients who had high ERG expression and FLT3 ITD had a 5-year OS of only 5%. - Conclusion: We analyzed a comprehensive set of molecular risk factors in a large, homogeneous CN-AML patient cohort. In this study, high ERG expression levels emerged as a strong negative prognostic factor and provided prognostic information in addition to established molecular markers

Acute myeloid leukemia with biallelic CEBPA gene mutations and normal karyotype represents a distinct genetic entity associated with a favorable clinical outcome.

Purpose CEBPA mutations are found as either biallelic (biCEBPA) or monoallelic (moCEBPA). We set out to explore whether the kind of CEBPA mutation is of prognostic relevance in cytogenetically normal (CN) acute myeloid leukemia (AML). Patients and Methods: Four hundred sixty-seven homogeneously treated patients with CN-AML were subdivided into moCEBPA, biCEBPA, and wild-type (wt) CEBPA patients. The subgroups were analyzed for clinical parameters and for additional mutations in the NPM1, FLT3, and MLL genes. Furthermore, we obtained gene expression profiles using oligonucleotide microarrays. Results: Only patients with biCEBPA had an improved median overall survival when compared with patients with wtCEBPA (not reached v 20.4 months, respectively; P = .018), whereas patients with moCEBPA (20.9 months) and wtCEBPA had a similar outcome (P = .506). Multivariable analysis confirmed biCEBPA, but not moCEBPA, mutations as an independent favorable prognostic factor. Interestingly, biCEBPA mutations, compared with wtCEBPA, were never associated with mutated NPM1 (0% v 43%, respectively; P < .001) and rarely associated with FLT3 internal tandem duplication (ITD; 5% v 23%, respectively; P = .059), whereas patients with moCEBPA had a similar frequency of mutated NPM1 and a significantly higher association with FLT3-ITD compared with patients with wtCEBPA (44% v 23%, respectively; P = .037). Furthermore, patients with biCEBPA showed a homogeneous gene expression profile that was characterized by downregulation of HOX genes, whereas patients with moCEBPA showed greater heterogeneity in their gene expression profiles. Conclusion: Biallelic disruption of the N and C terminus of CEBPA is required for the favorable clinical outcome of CEBPA-mutated patients and represents a distinct molecular subtype of CN-AML with a different frequency of associated gene mutations. These findings are of great significance for risk-adapted therapeutic strategies in AML

Monoallelic <em>CEBPA</em> mutations in normal karyotype acute myeloid leukemia: Independent favorable prognostic factor within <em>NPM1</em> mutated patients.

We and others have shown that cytogenetically normal (CN)-AML patients with biallelic CEBPA gene mutations (biCEBPA) represent a molecularly distinct group with a favorable prognosis. Patients carrying a monoallelic CEBPA mutation (moCEBPA), however, show no different outcome compared to patients with wildtype CEBPA, and these mutations are frequently associated with mutated NPM1 or FLT3-ITD. So far, no molecular or clinical hallmark has been identified to prognostically distinguish moCEBPA patients from patients with wildtype CEBPA. Therefore, we used the data of 663 CN-AML patients treated within the AMLCG 1999 trial to explore the prognostic value of moCEBPA in the context of concomitant clinical and molecular markers (mutated NPM1, FLT3-ITD). Multiple Cox regression in 515 patients adjusting for all available potential confounders revealed that the NPM1 mutation modified the prognostic value of moCEBPA with respect to overall survival (OS, p = 0.017) and event-free survival (EFS, p = 0.011). MoCEBPA was beneficial in NPM1 mutated patients: adjusted OS-hazard ratio (HR) 0.09, 95% confidence interval (CI) 0.01-0.63, p = 0.016; EFS-HR (95% CI) 0.16 (0.04-0.65), p = 0.010. In contrast, moCEBPA had no prognostic impact in patients with wildtype NPM1: OS-HR (95% CI) 1.08 (0.59-1.97), p = 0.804; EFS-HR (95% CI) 1.12 (0.64-1.96), p = 0.682. We found no prognostic effect modification for moCEBPA by FLT3-ITD. The presence of a moCEBPA mutation was shown to be associated with prolonged survival in NPM1 mutated CN-AML patients. Confirmation of these results in larger studies will clarify whether an additional moCEBPA mutation influences the risk stratification of patients with an NPM1 mutated/FLT3-ITD positive genotype

CBL exon 8/9 mutants activate the FLT3 pathway and cluster in core binding factor/11q deletion acute myeloid leukemia/myelodysplastic syndrome subtypes.

Purpose: CBL is a negative regulator of activated receptor tyrosine kinases (RTK). In this study, we determined the frequency of CBL mutations in acute leukemias and evaluated the oncogenic potential of mutant CBL. Experimental Design: The cDNA of 300 acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) and acute lymphoblastic leukemia (ALL) patients and 82 human leukemic cell lines was screened for aberrations in the linker and RING finger domain of CBL. The oncogenic potential of identified mutants was evaluated in hematopoietic cells. Results: We identified 3 of 279 AML/MDS patients expressing CBL exon 8/9 deletion mutants. Three of four cases at diagnosis expressed deleted transcripts missing exon 8 or exon 8/9. In remission samples a weak or no expression of mutant CBL was detected. No aberrations were found in normal hematopoietic tissues, One of 116 sequenced AML/MDS cases carried a R420G missense mutation. All AML/MDS patients with identified CBL mutants belonged to the core binding factor and 11q deletion AML subtypes. Functionally, CBL negatively regulated FMS-like tyrosine kinase 3 (FLT3) activity and interacted with human FLT3 via the autophosphorylation sites Y589 and Y599 and colocalized in vivo. Expression of CBL Delta exon8 and CBL Delta exon8+9 in FLT3-WT-Ba/F3 cells induced growth factor - independent proliferation associated with autophosphorylation of FILT3 and activated the downstream targets signal transducer and activator of transcription 5 (STAT5) and protein kinase B (AKT). FLT3 ligand - dependent hyperproliferation of CBL mutant cells could be abrogated by treatment with the FLT3 PTK inhibitor PKC412 (mid-ostaurin). Conclusion: CBL exon8/9 mutants occur in genetically defined AML/MDS subtypes and transform hematopoietic cells by constitutively activating the FLT3 pathway. This phenotype resembles the one of mutated RTKs and suggests that CBL mutant AML patients might benefit from treatment with FLT3 PTK inhibitors

The <em>FLT3</em>ITD mRNA level has a high prognostic impact in <em>NPM1</em> mutated, but not in <em>NPM1</em> unmutated, AML with a normal karyotype.

The impact of a FLT3-internal tandem duplication (FLT3ITD) on prognosis of patients with acute myeloid leukemia (AML) is dependent on the ratio of mutated to wild-type allele. In 648 normal karyotype (NK) AML patients, we found a significant independent effect of the quantitative FLT3ITD mRNA level-measured as (FLT3ITD/wtFLT3)/(FLT3ITD/wtFLT3 + 1)-on outcome. Moreover, this effect was clearly seen in 329 patients with a mutated NPM1 gene (NPM1(+)), but not in 319 patients without a NPM1 mutation (wtNPM1). In a multivariate Cox regression model, the quantitative FLT3ITD mRNA level showed an independent prognostic impact on overall survival (OS) and relapse-free survival (RFS) only in the NPM1(+) subgroup (OS: hazard ratio, 5.9; [95% confidence interval [CI]: 3.1-11.2]; RFS: hazard ratio, 7.5 [95% CI: 3.4-16.5]). The FLT3ITD mRNA level contributes to relapse risk stratification and might help to guide postremission therapy in NPM1-mutated AML