Exposure of breast cancer cells to hypoxia increases the percentage of breast cancer stem cells (BCSCs), which are required for tumor initiation and metastasis, and this response is dependent on the activity of hypoxia-inducible factors (HIFs). We previously reported that exposure of breast cancer cells to hypoxia induces the ALKBH5-mediated demethylation of N6-methyladenosine (m6A) in NANOG mRNA leading to increased expression of NANOG, which is a pluripotency factor that promotes BCSC specification. Here we report that exposure of breast cancer cells to hypoxia also induces ZNF217-dependent inhibition of m6A methylation of mRNAs encoding NANOG and KLF4, which is another pluripotency factor that mediates BCSC specification. Although hypoxia induced the BCSC phenotype in all breast-cancer cell lines analyzed, it did so through variable induction of pluripotency factors and ALKBH5 or ZNF217. However, in every breast cancer line, the hypoxic induction of pluripotency factor and ALKBH5 or ZNF217 expression was HIF-dependent. Immunohistochemistry revealed that expression of HIF-1α and ALKBH5 was concordant in all human breast cancer biopsies analyzed. ALKBH5 knockdown in MDA-MB-231 breast cancer cells significantly decreased metastasis from breast to lungs in immunodeficient mice. Thus, HIFs stimulate pluripotency factor expression and BCSC specification by negative regulation of RNA methylation.

PURPOSE The objective response rate (ORR) for single-agent anti–programmed death receptor 1 (anti–PD-1) therapy is modest in patients with metastatic or recurrent head and neck squamous cell carcinoma (HNSCC). We aimed to test whether radiotherapy may act synergistically with anti–PD-1 therapy to improve response through the abscopal effect. PATIENTS AND METHODS We conducted a single-center, randomized, phase II trial of nivolumab (anti–PD-1 therapy) versus nivolumab plus stereotactic body radiotherapy (SBRT) in patients with metastatic HNSCC. Patients had at least two metastatic lesions: one that could be safely irradiated and one measurable by RECIST version 1.1. Patients were randomly assigned (1:1), stratified by human papillomavirus status, to nivolumab (3 mg/kg intravenously every 2 weeks) or nivolumab (same dose) plus SBRT (9 Gy × 3) to 1 lesion. The primary end point was ORR in nonirradiated lesions, which was assessed by RECIST in patients with at least one available set of on-treatment images; safety was assessed in a per-protocol population. RESULTS Between March 11, 2016, and June 22, 2018, 62 patients were randomly assigned to nivolumab (n = 30) or nivolumab plus SBRT (n = 32). There was no statistically significant ORR difference between arms (34.5% [95% CI, 19.9% to 52.7%] v 29.0% [95% CI, 16.1% to 46.6%]; P = .86). There was no significant difference in overall survival ( P = .75), progression-free survival ( P = .79), or response duration ( P = .26). Grade 3-5 toxicities were similar (13.3% v 9.7%; P = .70). CONCLUSION We found no improvement in response and no evidence of an abscopal effect with the addition of SBRT to nivolumab in unselected patients with metastatic HNSCC.

Cancers of the appendix are rare. Most of them are found accidentally on appendectomies performed for appendicitis. When reviewed, majority of the tumors were carcinoid, adenoma, and lymphoma. Adenocarcinomas of appendix are only 0.08% of all cancers and the treatment remains controversial. Here we are reporting a 46-year-old male presented with symptoms of appendicitis, diagnosed with adenocarcinoma of the appendix. The patient was treated with appendectomy and refused further surgical intervention to complete hemicolectomy. Up to date, he remains asymptomatic. We performed literature review of the tumors of the appendix. Most of the benign conditions are treated with surgery alone. Lymphomas require CHOP-like chemotherapy and carcinoid syndrome treatment with somatostatin analogues. It is generally recommended that right hemicolectomy is the preferred treatment for adenocarcinoma of appendix. The role of chemotherapy is unclear due to lacking randomized trials but seems to be accepted if there is lymph node involvement or peritoneal seeding.