Targeting Nuclear Receptor Coactivator SRC-1 Prevents Colorectal Cancer Immune Escape by Reducing Transcription and Protein Stability of PD-L1.

Programmed death-ligand 1 (PD-L1) is overexpressed in multiple cancers and critical for their immune escape. It has previously shown that the nuclear coactivator SRC-1 promoted colorectal cancer (CRC) progression by enhancing CRC cell viability, yet its role in CRC immune escape is unclear. Here, we demonstrate that SRC-1 is positively correlated with PD-L1 in human CRC specimens. SRC-1 deficiency significantly inhibits PD-L1 expression in CRC cells and retards murine CRC growth in subcutaneous grafts by enhancing CRC immune escape via increasing tumor infiltration of CD8+ T cells. Genetic ablation of SRC-1 in mice also decreases PD-L1 expression in AOM/DSS-induced murine CRC. These results suggest that tumor-derived SRC-1 promotes CRC immune escape by enhancing PD-L1 expression. Mechanistically, SRC-1 activated JAK-STAT signaling by inhibiting SOCS1 expression and coactivated STAT3 and IRF1 to enhance PD-L1 transcription as well as stabilized PD-L1 protein by inhibiting proteasome-dependent degradation mediated by speckle type POZ protein (SPOP). Pharmacological inhibition of SRC-1 improved the antitumor effect of PD-L1 antibody in both subcutaneous graft and AOM/DSS-induced murine CRC models. Taken together, these findings highlight a crucial role of SRC-1 in regulating PD-L1 expression and targeting SRC-1 in combination with PD-L1 antibody immunotherapy may be an attractive strategy for CRC treatment.

Feasibility and tolerability of eribulin-based chemotherapy versus other chemotherapy regimens for patients with metastatic triple-negative breast cancer: a single-centre retrospective study.

Background: Patients with Triple-negative breast cancer (TNBC) face a poor prognosis and limited therapeutic options. Current data on eribulin usage to treat TNBC is scarce. Therefore, we sought to compare the feasibility and tolerability of eribulin-based regimens with other chemotherapy regimens in patients with TNBC. Method: This retrospective study was conducted at Fujian Medical University Cancer Hospital and included 159 patients with TNBC enrolled between October 2011 and January 2023. Patients underwent treatment with eribulin-based and other chemotherapy regimens. The study's primary endpoints were progression-free survival (PFS) and overall survival (OS), while its secondary endpoint was objective response rate (ORR), disease control rate (DCR), and safety. Tumour response was assessed using RECIST V.1.1 criteria. Results: Of the 159 participants in the study, 42 individuals (26.4%) received treatment with eribulin, whereas 117 participants (73.6%) were administered alternative chemotherapy regimens, which included nab-paclitaxel-based therapy (n = 45) and platinum-based therapy (n = 51). The follow-up period for all patients ended on 31 December 2022, and the median follow-up time was 18.3 months (range:0.7-27.5). Following propensity score matching (PSM), eribulin-based treatment resulted in longer median progression-free survival compared to platinum-based (hazard ratio (HR) = 0.41, p = 0.006), nab-paclitaxel-based (hazard ratio = 0.36, p = 0.001) and other chemotherapy (HR = 0.39, p < 0.001). Also, eribulin induced a remarkable prolongation of the median overall survival duration in all three comparative groups. The group receiving eribulin treatment showed significantly reduced incidences of any grade of anaemia, peripheral neuropathy, nausea and vomiting, and hair loss compared to other chemotherapy groups. Conclusion: For the salvage treatment of advanced TNBC, treatment with eribulin produced longer median PFS and OS than other chemotherapy regimens, with a well-tolerated safety profile. Therefore, further investigation of eribulin-based treatment in larger randomized trials for patients with advanced TNBC is warranted.

A real-world study of the effectiveness and safety of apatinib-based regimens in metastatic triple-negative breast cancer.

PURPOSE: This investigation sought to examine the efficacy and safety of low-dose apatinib used alongside chemotherapy in the clinical management of patients with metastatic triple-negative breast cancer (TNBC) within a real-world setting, whilst comparing the outcomes with those treated solely with chemotherapy. METHODS: This case series study analyzed clinical data and treatment outcomes of 163 patients with metastatic TNBC who underwent rescue treatment at the Medical Oncology Department of Clinical Oncology, Fujian Cancer Hospital, School of Fujian Medical University, China, between October 2011 and January 2023. All the patients underwent rescue treatment with either chemotherapy alone or apatinib (250 mg/day) combined with chemotherapy. The study's primary outcome was progression-free survival (PFS), whereas the secondary outcomes included overall survival (OS), objective response rate (ORR), disease control rate (DCR), and safety profiles. RESULTS: The study was designed to compare two groups [1]. Out of the 163 TNBC patients who participated in the study, 107 individuals (65.6%) received treatment based on chemotherapy, whereas 56 patients (34.4%) were given treatment based on a combination of low-dose apatinib (250 mg/day) and other treatments, including chemotherapy. After propensity score matching (PSM), the objective response rate (ORR) and disease control rate (DCR) of patients with advanced triple-negative breast cancer (TNBC) who received apatinib-based treatment were 50.0 and 90.0%, respectively, while they were 6.7 and 20.0%, respectively, for the chemotherapy-based group (P < 0.001). The group that received apatinib-based treatment showed superior results in both PFS and OS compared to the group that received chemotherapy. The median PFS and OS for the apatinib-based group were 7.8 and 20.3 months, respectively, while they were only 2.2 months and 9.0 months, respectively, for the chemotherapy-based group (P < 0.001) [2]. Patients who were administered combo therapies, including PD-1 inhibitors, were excluded. In total, 97 patients received chemotherapy alone, while 34 patients were treated with apatinib in combination with chemotherapy. After propensity score matching (PSM), the ORR and DCR for the total group who received combo therapies were 44.4 and 81.5%, respectively, while they were 11.1 and 22.2%, respectively, for the chemotherapy alone group (P < 0.001). The group receiving both apatinib and chemotherapy displayed notable advantages over the group solely receiving chemotherapy in regards to PFS and OS for the entirety of the population. The PFS was found to be 7.8 months in comparison to 2.1 months (P < 0.001) and the OS was 21.1 months in contrast to 9.0 months (P < 0.001). Apatinib combined with chemotherapy induced grade 3/4 hematological toxicities, including neutropenia (8.8%) and thrombocytopenia (2.9%). Additionally, non-hematological toxicities were commonly observed, such as Hand-foot syndrome (35.3%), proteinuria (26.5%), hypertension (61.8%), higher alanine aminotransferase levels (26.5%), and fatigue (35.3%). The most frequent non-hematological grade 3/4 toxicities were Hand-foot syndrome (2.9%) and hypertension (5.9%). The study did not report any fatal adverse effects. CONCLUSIONS: The combination of low-dose apatinib with chemotherapy has proven to be more effective than chemotherapy alone in treating metastatic triple-negative breast cancer (TNBC). Additionally, the occurrence of grade 3/4 non-hematologic toxicities was significantly lower compared to the recommended dose of apatinib.

Abnormal variation and prognostic significance of circulating immune cells in patients with nasopharyngeal carcinoma treated with chemoradiotherapy: a prospective cohort study.

Background: Circulating immune cells are associated with tumor development and poor prognosis in multiple solid tumors. However, the circulating immune-cell profile of nasopharyngeal carcinoma (NPC) remains largely unknown. Therefore, we aimed to determine the changes in immune status and the prognostic significance of circulating immune cells before and after chemoradiotherapy (CRT) in patients, which can provide clinicians with valuable insights to optimize treatment strategies, monitor immune function, and personalize interventions, ultimately improving patient outcomes. Methods: Circulating immune cells before and after CRT in 77 patients with NPC and in 30 healthy controls were measured with flow cytometry. A thorough follow-up was conducted to assess prognosis outcomes, including local failure-free rate (LFFR), distant failure-free rate (DFFR), disease-free survival (DFS), and overall survival (OS). The differences of the subpopulation distribution in the two groups were determined by t-tests or Mann-Whitney tests. The paired t-test or Wilcoxon matched-pairs signed rank test was used to compare differences in lymphocyte subsets before and after CRT. The prognostic significance of lymphocyte subsets was evaluated by Kaplan-Meier analysis and Cox proportional hazards model. Results: Compared with the control group, the NPC group showed significant decreases in the proportions of CD3+ cells, CD4+ T cells, CD8+CD28+ T cells, and CD19+ B cells as well as the CD4+:CD8+ ratio (P<0.05) but a significant increase in the proportion of natural killer (NK) cells (P<0.05). After CRT, the proportions of CD4+ cells, CD8+CD28+ T cells, and CD19+ B cells as well as the CD4+:CD8+ ratio were markedly decreased (P<0.05), while the proportions of CD8+ T cells and NK cells were significantly increased (P<0.05). Multivariate analysis showed that a lower percentage of CD19+ B cells [hazard ratio (HR) 6.550, 95% CI: 1.661-25.831; P=0.007] and a positive test for Epstein-Barr virus (EBV) DNA (HR 0.261, 95% CI: 0.074-0.926; P=0.038) before treatment independently predicted worse 5-year OS (P<0.05). Conclusions: The disproportion of circulating immune cells was observed in patients with NPC before treatment. CRT further aggravated immune dysfunction. Notably, a lower percentage of CD19+ B cells and EBV DNA-positive status before treatment were independent predictors of a worse prognosis. Thus, the measurement of circulating immune cells may help elucidate immune function status and predict the outcomes of patients with NPC.