LMX1A as a prognostic marker in ovarian mucinous cystadenocarcinoma

Lmx1a is required for the development of the ovarian stem cell niche in Drosophila

The Drosophila ovary serves as a model for pioneering studies of stem cell niches, with defined cell types and signaling pathways supporting both germline and somatic stem cells. The establishment of the niche units begins during larval stages with the formation of terminal filament-cap structures; however, the genetics underlying their development remains largely unknown. Here, we show that the transcription factor Lmx1a is required for ovary morphogenesis. We found that Lmx1a is expressed in early ovarian somatic lineages and becomes progressively restricted to terminal filaments and cap cells. We show that Lmx1a is required for the formation of terminal filaments, during the larval-pupal transition. Finally, our data demonstrate that Lmx1a functions genetically downstream of Bric-à-Brac, and is crucial for the expression of key components of several conserved pathways essential to ovarian stem cell niche development. Importantly, expression of chicken Lmx1b is sufficient to rescue the null Lmx1a phenotype, indicating functional conservation across the animal kingdom. These results significantly expand our understanding of the mechanisms controlling stem cell niche development in the fly ovary.

Correlation between lung neoplasm and serum level of osteopontin: A meta-analysis

The aim of this meta-analysis was to evaluate the clinical significance of serum osteopontin (OPN) levels in lung neoplasm in patients to establish a novel diagnostic score model. Articles were identified by searching the PubMed, Web of Science, Google Scholar, China National Knowledge Infrastructure, and Wang Fang databases. Studies identified were pooled, and the standardized mean difference (SMD) and its corresponding 95% confidence interval (CI) were calculated. Subgroup analyses and publication bias detection were also conducted. Version 12.0 STATA software was used for statistical analysis. A final analysis of 1,327 subjects together (740 patients with lung neoplasms and 587 controls) was performed from 10 clinical case-control studies. The meta-analysis results showed a positive association between serum OPN levels and lung neoplasm (SMD=5.59, 95% CI: 1.85–3.32, P<0.001). The subgroup analysis by ethnicity detected that high levels of serum OPN may be the main risk factor for lung neoplasms in Asians (SMD=1.76, 95% CI: 1.24–2.29, P<0.001), but not in Caucasians (P=0.072). In conclusion, the present meta-analysis indicated that serum OPN levels were generally elevated in lung neoplasm patients, and thus, serum levels of OPN may be useful in diagnosing lung neoplasm in certain population groups.

Cell fate determination, neuronal maintenance and disease state: The emerging role of transcription factors Lmx1a and Lmx1b

LIM-homeodomain (LIM-HD) proteins are evolutionary conserved developmental transcription factors. LIM-HD Lmx1a and Lmx1b orchestrate complex temporal and spatial gene expression of the dopaminergic pathway, and evidence shows they are also involved in adult neuronal homeostasis. In this review, the multiple roles played by Lmx1a and Lmx1b will be discussed. Controlled Lmx1a and Lmx1b expression and activities ensure the proper formation of critical signaling centers, including the embryonic ventral mesencephalon floor plate and sharp boundaries between lineage-specific cells. Lmx1a and Lmx1b expression persists in mature dopaminergic neurons of the substantia nigra pars compacta and the ventral tegmental area, and their role in the adult brain is beginning to be revealed. Notably, LMX1B expression was lower in brain tissue affected by Parkinson's disease. Actual and future applications of Lmx1a and Lmx1b transcription factors in stem cell production as well as in direct conversion of fibroblast into dopaminergic neurons are also discussed. A thorough understanding of the role of LMX1A and LMX1B in a number of disease states, including developmental diseases, cancer and neurodegenerative diseases, could lead to significant benefits for human healthcare.

Correlation between ovarian neoplasm and serum levels of osteopontin: a meta-analysis

The aim of this meta-analysis was to evaluate the clinical significance of serum osteopontin (OPN) levels in ovarian neoplasm in patients, with the goal of building a novel diagnostic score model. By searching the PubMed, Embase, Web of Science, Cochrane Library, CISCOM, CINAHL, Google Scholar, CBM, and China National Knowledge Infrastructure (CNKI) databases, we conducted a meta-analysis. Studies were pooled, and the standardized mean difference (SMD) and its corresponding 95 % confidence interval (CI) were calculated. Subgroup analyses and publication bias detection were also conducted. Version 12.0 STATA software was used for statistical analysis. We performed a final analysis of 1,653 subjects altogether (822 patients with psoriasis and 831 healthy controls) from 15 clinical case-control studies. The meta-analysis results showed a positive association between serum OPN levels and ovarian neoplasm (SMD = 2.60, 95 %CI 1.88-3.32, P < 0.001). The subgroup analysis by ethnicity detected that high levels of serum OPN may be the main risk factor for ovarian neoplasms in Asians (SMD = 2.91, 95 %CI 2.38-3.45, P < 0.001), but not in Caucasians (P > 0.05). The present meta-analysis indicated that serum OPN levels were generally elevated in ovarian neoplasm patients, and thus, serum levels of OPN could be useful in diagnosing ovarian neoplasm.

Gene expression profile is associated with chemoradiation resistance in rectal cancer

AIM

Patients with rectal cancer who achieve a complete pathological response after preoperative chemoradiation (CRT) have an improved oncological outcome. Identifying factors associated with a lack of response could help our understanding of the underlying biology of treatment resistance. This study aimed to develop a gene expression signature for CRT-resistant rectal cancer using high-throughput nucleotide microarrays.

METHOD

Pretreatment biopsies of rectal adenocarcinomas were prospectively collected and freshly frozen according to an institutional review board-approved protocol. Total tumour mRNA was extracted and gene expression levels were measured using microarrays. Patients underwent proctectomy after completing standard long-course CRT and the resected specimens were graded for treatment response. Gene expression profiles for nonresponders were compared with those of responders. Differentially expressed genes were analyzed for functional significance using the Ingenuity Pathway Analysis (IPA) software.

RESULTS

Thirty-three patients treated between 2006 and 2009 were included. We derived 812-gene and 183-gene signatures separating nonresponders from responders. The classifiers were able to identify nonresponders with a sensitivity and specificity of 100% using the 812-gene signature, and sensitivity and specificity of 33% and 100% using the 183-gene signature. IPA canonical pathway analysis revealed a significant ratio of differentially expressed genes in the 'DNA double-strand break repair by homologous recombination' pathway.

CONCLUSION

Certain rectal cancer gene profiles are associated with poor response to CRT. Alterations in the DNA double-strand break repair pathway could contribute to treatment resistance and provides an opportunity for further studies.