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Refractory ulcers are a major challenge in the treatment of a diabetic foot, because of the immunodeficient, ischemic and high-glucose microenvironment. Inflammatory memory peptides, which were extracted from the immune mediator absent in melanoma 2 (AIM2), could effectively improve the immunodeficient microenvironment and special angiogenic peptides could effectively promote angiogenesis. Moreover, the gut flora Akkermansia muciniphila (A. muciniphila) participates in diabetic metabolism and could decrease high-glucose levels. In this research, a polypeptide skeleton (PPS) was synthesized based on 3,4-dihydroxyphenylalanine (DOPA) and peptides, forming the hydrophilic and hydrophobic parts. Inflammatory memory peptides and angiogenic peptides were synthesized and conjugated with the PPS, which then formed an anisotropic hydrogel through the self-assembling of β-sheet peptides based on hydrophobicity and DOPA oxidation. A. muciniphila was seeded into the hydrogel and transported into diabetic ischemic ulcers through subcutaneous injection, and the healing of diabetic ischemic ulcers was promoted. The inflammatory memory peptides were released based on the A. muciniphila enzyme response, and they firstly improved the immunity of the local surroundings. Then, the angiogenic peptides were also released through irradiation and they promoted angiogenesis. Additionally, the transported A. muciniphila could decrease the local glucose levels and spontaneously regress once the diabetic ischemic ulcers had healed. A. muciniphila combined with a functional polypeptide hydrogel may be a novel strategy for diabetic ischemic ulcer treatment.

Rationale: Mutation p.A289V involving extracellular region of epidermal growth factor receptor (EGFR) exon 7 has not yet been reported in nonsmall cell lung cancer (NSCLC). Studies have shown p.A289V mutation responding to tyrosine kinase inhibitors (TKIs) in glioblastoma cell lines suggesting the point mutation as a potential therapeutic target. However, sufficient evidence of the effect of TKI treatment on the p.A289V mutation involved in NSCLC is not available. Patient concerns: An 80-year-old nonsmoker male with lung mass was suffering from severe bone pain. Diagnosis: Needle biopsy and positron emitted tomography/computed tomography were performed. The patient was diagnosed with advanced NSCLC adenocarcinoma with bone and lymphatic metastasis. Next-generation sequencing of circulating tumor DNA was performed, which identified a p.A289V mutation in the EGFR gene of the patient. Interventions: Our patient refused to receive chemotherapy and tried Icotinib treatment. Outcomes: Our patient had a partial response to Icotinib after treatment for 5 months during the therapeutic trial by TKIs. The patient showed adverse symptoms of mild diarrhea and rash (Common Terminology Criteria for Adverse Events grade 1) during the treatment. Lessons: In this case, Icotinib prevented completion of the signal transduction cascade of p.A289V mutant in NSCLC. Our finding may expand the EGFR mutation spectrum for TKI treatment in NSCLC. However, the finding needs to be confirmed at a larger scale with NSCLC in Chinese and other populations.