RESUMO
Platinum resistance represents a major barrier to the survival of patients with ovarian cancer (OC). Cdc2-like kinase 2 (CLK2) is a major protein kinase associated with oncogenic phenotype and development in some solid tumors. However, the exact role and underlying mechanism of CLK2 in the progression of OC is currently unknown. Using microarray gene expression profiling and immunostaining on OC tissues, we found that CLK2 was upregulated in OC tissues and was associated with a short platinum-free interval in patients. Functional assays showed that CLK2 protected OC cells from platinum-induced apoptosis and allowed tumor xenografts to be more resistant to platinum. Mechanistically, CLK2 phosphorylated breast cancer gene 1 (BRCA1) at serine 1423 (Ser1423) to enhance DNA damage repair, resulting in platinum resistance in OC cells. Meanwhile, in OC cells treated with platinum, p38 stabilized CLK2 protein through phosphorylating at threonine 343 of CLK2. Consequently, the combination of CLK2 and poly ADP-ribose polymerase inhibitors achieved synergistic lethal effect to overcome platinum resistance in patient-derived xenografts, especially those with wild-type BRCA1. These findings provide evidence for a potential strategy to overcome platinum resistance in OC patients by targeting CLK2.
RESUMO
Background: Sintilimab is an antibody against programmed cell death protein 1. We assessed the efficacy and safety of sintilimab plus albumin-bound (nab)-paclitaxel for the treatment of recurrent or metastatic cervical cancer. Methods: This multicenter, open-label, single-arm, phase II study (ClinicalTrials.gov identifier NCT04341883) enrolled patients with recurrent or metastatic cervical cancer who progressed after at least one line of systemic therapy. The patients received sintilimab 200 mg and nab-paclitaxel 260 mg/m2 body surface area every 3 weeks. The primary endpoint was objective response rate (ORR) assessed by investigators per Response Evaluation Criteria in Solid Tumors version 1.1. Key secondary endpoints were progression-free survival (PFS), overall survival (OS), duration of response (DoR), and safety. Findings: From January 13, 2020 to February 21, 2022, 27 patients were enrolled and received treatment. Median patient age was 50 years (range, 34-68 years). By data cut-off (May 22, 2022), in intention-to-treat population, ORR was 44.4% (95% CI, 24.4%-64.5%). The disease control rate was 88.9% (95% CI, 70.8%-97.6%). Median PFS was 5.2 months (95% CI, 2.7-7.7 months). Median DoR was 3.8 months (95% CI, 0.7-6.9 months), and median OS was 13.1 months (95% CI, 5.8-20.4 months). Treatment-related grade 3 or 4 adverse events (AEs) occurred in 44.4% of the patients, and the most common AEs were decreased neutrophil count (22.2%), decreased white blood cell count (14.8%), and anemia (7.4%). The most common potential immune-related AEs were grade 1-2 hypothyroidism (18.5%), neutropenia (11.1%), and rash (7.4%). Interpretation: Sintilimab plus nab-paclitaxel treatment shows promising antitumor activity and manageable toxicity in patients with advanced cervical cancer. Larger randomized controlled trials are required for validation. Funding: Innovent Biologics Co., Ltd.; Csps Holdings Co., Ltd.