Systemic chemotherapy plus cetuximab after complete surgery in the treatment of isolated colorectal peritoneal carcinoma: COCHISE phase II clinical trial

Controversies around the treatment of peritoneal metastases of colorectal cancer

In this editorial we examine the article by Wu et al published in the World Journal of Gastrointestinal Oncology. Surgical resection for peritoneal metastases from colorectal cancer (CRC) has been gradually accepted in the medical oncology community. A randomized trial (PRODIGE 7) on cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) failed to prove any benefit of oxaliplatin in the overall survival of patients with peritoneal metastases from colorectal origin. Nevertheless, isolated systemic chemotherapy for CRC stage IV has demonstrated a reduced response in peritoneal metastases than that obtained in other metastatic sites such as the liver. Another tool is required in those patients to achieve more local control of the disease. Surgical groups in peritoneal surgery continue to use HIPEC in their procedures, using other agents than oxaliplatin for peritoneal cavity infusion, such as mitomycin C. These patients present with complex surgical issues to manage, and consequently a large burden of complications has to be anticipated. Therefore, identifying patients who will benefit from CRS with or without HIPEC would be of great interest.

NK cells and the profile of inflammatory cytokines in the peripheral blood of patients with advanced carcinomas

BACKGROUND

Natural killer (NK) cells are one of the most crucial immune cells that mediate the antitumoral response due to their ability to immediately recognize and eliminate transformed cells. Because of their great cytotoxic activity, the function of NK cells must be robustly regulated to avoid tissue damage. Such regulation is mediated by a coordinated engagement of activating (NKp46) and inhibitory (CD158b) receptors, which tumor cells may use to escape from immunosurveillance. Also, NK cells are generally divided based on surface molecules, such as CD16 and CD56, and can be classified as CD56brightCD16- (regulatory) and CD56dimCD16+ (cytotoxic) NK cells. Here, we aimed to evaluate the frequency and phenotype of circulating NK cells in patients with advanced carcinomas, as well as their systemic cytokine/chemokine and growth factors production.

METHODS

Peripheral blood was collected from 24 patients with advanced solid cancer during or after treatment and from 10 healthy donors. The frequency and the expression of activating (NKp46) and inhibitory (CD158b) molecules of CD56brightCD16- and CD56dimCD16+ NK cells were assessed by flow cytometry and the multiplex Luminex platform was used to quantify the secreted factors in peripheral blood serum.

RESULTS

Cancer patients had a lower frequency of the cytotoxic CD56dim CD16+ NK cells subset in comparison with healthy controls. Also, the regulatory CD56bright CD16- NKs isolated from cancer patients exhibited a significantly lower expression of NKp46. Among 29 immunological and growth factors analyzed in the peripheral blood of oncologic patients, MCP-1, IP-10, and eotaxin, and VEGF they have presented a higher proportion. The Pearson correlation test showed that IL-12p40 positively correlates with CD56brightCD16- NK cells. We also observed a positive correlation between MCP-1 and the activating marker NKp46, as well as a negative correlation between IP-10 and TNF-α and NKp46. CD158b expression in CD56dimCD16+ was positively correlated with EGF and negatively correlated with MIP-1β.

CONCLUSIONS

Taken together, these results suggest that cancer patients present a shift towards a poorly cytotoxic and less activated NK profile which may contribute to tumor development and progression. The understanding of NK cell biology and soluble factors during tumor development could aid in the design of possible targeting therapeutic approaches.