Prehabilitation services for people diagnosed with cancer in Scotland - Current practice, barriers and challenges to implementation.

BACKGROUND: Prehabilitation is the practice of enhancing a patient's functional and psychological capacity before treatment commences. It is of interest in the cancer context because of the impact of treatments on quality of life and cancer survivorship. This work aims to document current practice, barriers and challenges to implementing prehabilitation to inform the development of a national framework. METHODS: A mixed-methods approach was applied: an on-line survey was sent to stakeholders in cancer care across Scotland, supplemented by in-depth interviews. Key domains explored were the perceived importance of prehabilitation, availability, delivery and content of services, outcome measures, referral processes and funding. FINDINGS: A total of 295 survey responses were obtained and 11 interviews completed. Perceived importance of prehabilitation was rated highly. There was uncertainty over the definition of prehabilitation and most respondents did not know if local services were available. Where services were described, a range of health professionals were involved, different outcome measures were utilised and frequency of referrals varied. Respondents highlighted short time frames between referral and treatment, concerns about patient engagement, the evidence base for action and funding priorities. Respondents also commented on which context a referral should be made and to whom, and the need for equity of service across the country. CONCLUSIONS: The current work found clear evidence of the perceived importance of prehabilitation in cancer patients. However, issues and key gaps were identified within current services (including issues arising from COVID-19) which must be addressed to enable wide-spread development and implementation of equitable programmes.

Mammary epithelial-specific disruption of the focal adhesion kinase blocks mammary tumor progression.

Elevated expression and activation of the focal adhesion kinase (FAK) occurs in a large proportion of human breast cancers. Although several studies have implicated FAK as an important signaling molecule in cell culture systems, evidence supporting a role for FAK in mammary tumor progression is lacking. To directly assess the role of FAK in this process, we have used the Cre/loxP recombination system to disrupt FAK function in the mammary epithelium of a transgenic model of breast cancer. Using this approach, we demonstrate that FAK expression is required for the transition of premalignant hyperplasias to carcinomas and their subsequent metastases. This dramatic block in tumor progression was further correlated with impaired mammary epithelial proliferation. These observations provide direct evidence that FAK plays a critical role in mammary tumor progression.

Percutaneous computed tomography-guided gastric remnant access after laparoscopic Roux-en-Y gastric bypass.

BACKGROUND: The bypassed portion of the stomach is difficult to access and evaluate after Roux-en-Y gastric bypass. Access to the excluded stomach may be needed for nutritional support or decompression owing to acute distension and obstruction. We report our experience with percutaneous, computed tomography (CT)-guided gastrostomy tube placement into the gastric remnant after laparoscopic Roux-en-Y gastric bypass (LRYGB). METHODS: Of 569 consecutive LRYGB procedures performed, 9 patients underwent successful percutaneous, CT-guided gastrostomy placement. One additional patient was referred from another facility. We reviewed the indications, interval from surgery to the intervention, interval to removal, complications, and success or outcome of the procedure in our patient population. RESULTS: Ten patients underwent percutaneous, CT-guided gastric remnant gastrostomy tube placement. The indications included distended gastric remnant in 6, nutritional access in 4, and remnant drainage after leak in 1. Of the 10 patients, 2 had undergone previous gastric operations. The attempt at percutaneous gastrostomy was unsuccessful in 1 additional patient, who subsequently required laparoscopic gastrostomy (success rate 91%). CONCLUSION: In selected patients after LRYGB, CT-guided gastrostomy tube placement is safe and efficient. It may be used to manage complications of LRYGB, serve as a bridge to definitive surgery, or offer a convenient route for enteral nutritional support.

The role of focal-adhesion kinase in cancer - a new therapeutic opportunity.

Focal-adhesion kinase (FAK) is an important mediator of growth-factor signalling, cell proliferation, cell survival and cell migration. Given that the development of malignancy is often associated with perturbations in these processes, it is not surprising that FAK activity is altered in cancer cells. Mouse models have shown that FAK is involved in tumour formation and progression, and other studies showing that FAK expression is increased in human tumours make FAK a potentially important new therapeutic target.

Specific deletion of focal adhesion kinase suppresses tumor formation and blocks malignant progression.

We have generated mice with a floxed fak allele under the control of keratin-14-driven Cre fused to a modified estrogen receptor (CreER(T2)). 4-Hydroxy-tamoxifen treatment induced fak deletion in the epidermis, and suppressed chemically induced skin tumor formation. Loss of fak induced once benign tumors had formed inhibited malignant progression. Although fak deletion was associated with reduced migration of keratinocytes in vitro, we found no effect on wound re-epithelialization in vivo. However, increased keratinocyte cell death was observed after fak deletion in vitro and in vivo. Our work provides the first experimental proof implicating FAK in tumorigenesis, and this is associated with enhanced apoptosis.

Focal adhesion kinase as a potential target in oncology.

Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that plays a pivotal role in signal transduction at integrin-linked cellular adhesions, which mediate cell contact with the extracellular matrix. It has been shown to play a role in the survival of anchorage-dependent cells and to be essential for integrin-linked cell migration - processes that are likely to play important roles in the development of malignancies. FAK is upregulated in a wide variety of human epithelial cancers, with expression being closely correlated to invasive potential. Recently, evidence has emerged directly linking FAK expression to tumour development in vivo, raising the possibility that intervention strategies to block FAK function may potentially provide an opportunity for the development of anticancer therapeutics.

Src-induced de-regulation of E-cadherin in colon cancer cells requires integrin signalling.

Although Src expression and activity are often elevated in colon cancer, the precise consequences of overexpression of the non-catalytic Src homology (SH) domains, or enhanced catalytic activity, are unknown. We show that, in KM12C colon cancer cells, elevated Src activity causes the components of adherens junctions, including vinculin, to be redistributed to Src-induced integrin adhesion complexes. Specifically, elevated Src activity blocks proper assembly of cell cell contacts after cells are switched from media containing a low level of calcium to media containing a high level of calcium, and E-cadherin remains internalized. In contrast, although elevated expression of the non-catalytic domains of Src is sufficient to induce assembly of integrin adhesion complexes, it does not induce disorganization of E-cadherin-associated intercellular contacts. Surprisingly, Src-induced disruption of E-cadherin localization requires specific integrin signalling, because E-cadherin redistribution is blocked by loss of cell-matrix interaction, or by inhibitory antibodies to alpha(v) or beta(1) integrin subunits. Furthermore, phosphorylation of the integrin-regulated focal adhesion kinase (FAK) on Src-specific sites is required for Src-induced de-regulation of E-cadherin, demonstrating interdependence between integrin-induced signals and cadherin-associated adhesion changes induced by Src.