Targeted therapy for colorectal cancer resistance to EGF receptor antibodies and new trends

Innate lymphoid cells in intestinal cancer development

Colorectal cancer (CRC) is a highly prominent cause of cancer-related deaths worldwide. Although the functions of immune cells in the colorectal tumor microenvironment are complex and heterogeneous, dysregulated changes in the composition and activation state of immune cells are believed to represent key events supporting the establishment of pro- or anti-tumorigenic immune states. Recently, innate lymphoid cells (ILCs) emerged as central innate immune mediators during both gastrointestinal homeostasis and inflammatory pathologies. Hence, ILCs might also represent promising targets in the context of cancer therapy and are increasingly recognized as innate immune cells with potent immunomodulatory properties. In this review, we summarize the pleiotropic roles of the different ILC subsets for intestinal homeostasis and discuss the recent evidence on their potential involvement in the development and growth of intestinal cancers.

Serum EGF and NGF levels of patients with brain injury and limb fracture

OBJECTIVE

To explore the expression and significance of human epidermal growth factor (EGF) and nerve growth factor (NGF) in patients with knee osteoarthritis.

METHODS

RT-PCR and enzyme-linked immunosorbent assay were used to measure the serum EGF and NGF expression levels of patients with limb fracture and brain trauma injurry after 1 d, 3 d, 7 d, 14 d and the relationship between them was analyzed. The level was compared among the simple fracture group, traumatic brain injury group and the normal control group, with 40 cases in each group.

RESULTS

The serum NGF levels were significantly different among three groups. Serum NGF, EGF mRNA and protein levels gradually decreased with the increasing injury time in the limb fracture combined with brain injury group, traumatic brain injury group, the simple fracture group and the health control group (P<0.05).

CONCLUSIONS

The serum of NGF, EGF levels significantly increased when limb fracture combined with brain injury, so EGF and NGF may be involved in the process of fracture healing.

Lack of anti-tumor activity with the β-catenin expression inhibitor EZN-3892 in the C57BL/6J Min/+ model of intestinal carcinogenesis

BACKGROUND

Previously, we showed that short-term inhibition of β-catenin expression and reversal of aberrant β-catenin subcellular localization by the selective COX-2 inhibitor celecoxib is associated with adenoma regression in the C57BL/6J Min/+ mouse. Conversly, long-term administration resulted in tumor resistance, leading us to investigate alternative methods for selective β-catenin chemoprevention. In this study, we hypothesized that disruption of β-catenin expression by EZN-3892, a selective locked nucleic acid (LNA)-based β-catenin inhibitor, would counteract the tumorigenic effect of Apc loss in Min/+ adenomas while preserving normal intestinal function.

MATERIALS AND METHODS

C57BL/6J Apc(+/+) wild-type (WT) and Min/+ mice were treated with the maximum tolerated dose (MTD) of EZN-3892 (30mg/kg). Drug effect on tumor numbers, β-catenin protein expression, and nuclear β-catenin localization were determined.

RESULTS

Although the tumor phenotype and β-catenin nuclear localization in Min/+ mice did not change following drug administration, we observed a decrease in β-catenin expression levels in the mature intestinal tissue of treated Min/+ and WT mice, providing proof of principle regarding successful delivery of the LNA-based antisense vehicle. Higher doses of EZN-3892 resulted in fatal outcomes in Min/+ mice, likely due to β-catenin ablation in the intestinal tissue and loss of function.

CONCLUSIONS

Our data support the critical role of Wnt/β-catenin signaling in maintaining intestinal homeostasis and highlight the challenges of effective drug delivery to target disease without permanent toxicity to normal cellular function.