TGFβ signalling pathway impacts brain metastases profiles in locally advanced colorectal cancer

RATIONALE

Colorectal Cancer (CRC) represents the third most common type of cancer in Germany and the second most common cancer-related cause of death worldwide. Distant metastases are still the main limit for patient survival. While liver metastases as well as peritoneal carcinomatosis can often either be resected or treated with systemic therapy, little options remain for brain metastases. Additionally, a number of studies has already investigated hepatic, peritoneal, pulmonary as well as continuing distant metastases in colorectal cancer. Yet, with respect to tumor biology and brain metastases, little is known so far.

MATERIAL AND METHODS

Two cohorts, M0 without distant spread and BRA with brain metastases were build. RNA was isolated from paraffin embedded specimen. Gene expression was performed by an RNA NanoString-Analysis using the nCounter® PanCancer Progression Panel by NanoString-Technologies (Hamburg, Germany). Results were analysed by principal component analysis, gene expression and pathway analysis using commonly available databases such as KEGG as benchmark for comparison.

RESULTS

We were able to determine a gene signature that provides a sophisticated group separation between M0 and BRA using principal component analysis. All genes with strong loading characteristics on principal component 1 were cross-referenced with the subsequently performed accurate gene set enrichment analysis (GSEA). The GSEA revealed a clear dysregulation of the TGFβ pathway in compared cohorts M0 and BRA. Interestingly, the targeted pathways analysis of the identified genes confirmed that in fact almost all strong loading genes of PC1 play a role in the TGFβ pathway.

CONCLUSION

Our results suggest the TGFβ pathway as a crucial player in the development of brain metastases in primary CRC. In some types of colorectal cancer, downregulation of the TGFβ pathway might hinder primary colorectal cancer to metastasize to the nervous system. While the paradoxical functioning of the TGFβ pathway is still not fully understood, these shed light on yet another clinical implication of this complex pathway.

Endoscopic Management of Clinically Severe Obesity: Primary and Secondary Therapeutic Procedures

PURPOSE OF REVIEW

In the treatment of epidemic obesity and metabolic disorders, conservative approaches often fail to achieve the treatment goal in patients with very high BMI. To date, bariatric surgery accomplishes the most sustainable results in patients with morbid obesity. This leads to a treatment gap for lower and middle classes of obesity defined by BMI. Primary endoscopic procedures, which are less invasive than surgery, may be able to sufficiently fill this gap. Furthermore, secondary endoscopic procedures have developed into an essential addition regarding complication management of bariatric surgeries. The purpose of this review was to point out the latest developments in the field of bariatric endoscopy, including both primary and secondary procedures.

RECENT FINDINGS

Innovative devices and their possible applications will be discussed. These include various endoscopic suturing techniques as well as newly developed implants for the upper gastrointestinal tract to counteract the obesity epidemic. The growing understanding of the pathophysiology of obesity and the role of the gastrointestinal tract allows for the development of more effective endoscopic procedures regarding obesity treatment.