Apatinib Combined with Local Irradiation Leads to Systemic Tumor Control via Reversal of Immunosuppressive Tumor Microenvironment in Lung Cancer.

PURPOSE: This study aimed to investigate the potential systemic antitumor effects of stereotactic ablative radiotherapy (SABR) and apatinib (a novel vascular endothelial growth factor receptor 2 inhibitor) via reversing the immunosuppressive tumor microenvironment for lung carcinoma. MATERIALS AND METHODS: Lewis lung cancer cells were injected into C57BL/6 mice in the left hindlimb (primary tumor; irradiated) and in the right flank (secondary tumor; nonirradiated). When both tumors grew to the touchable size, mice were randomly divided into eight treatment groups. These groups received normal saline or three distinct doses of apatinib (50 mg/kg, 150 mg/kg, and 200 mg/kg) daily for 7 days, in combination with a single dose of 15 Gy radiotherapy or not to the primary tumor. The further tumor growth/regression of mice were followed and observed. RESULTS: For the single 15 Gy modality, tumor growth delay could only be observed at the primary tumor. When combining SABR and apatinib 200 mg/kg, significant retardation of both primary and secondary tumor growth could be observed, indicated an abscopal effect was induced. Mechanism analysis suggested that programmed death-ligand 1 expression increased with SABR was counteract by additional apatinib therapy. Furthermore, when apatinib was combined with SABR, the composition of immune cells could be changed. More importantly, this two-pronged approach evoked tumor antigen-specific immune responses and the mice were resistant to another tumor rechallenge, finally, long-term survival was improved. CONCLUSION: Our results suggested that the tumor microenvironment could be managed with apatinib, which was effective in eliciting an abscopal effect induced by SABR.

Safety and efficacy of PD-1 blockade-activated multiple antigen-specific cellular therapy alone or in combination with apatinib in patients with advanced solid tumors: a pooled analysis of two prospective trials.

BACKGROUND: The lethal effects of multiple antigen-specific cellular therapy (MASCT) may be enhanced by blocking PD-1 in vitro and vascular endothelial growth factor receptor 2 inhibitor (apatinib). We analyzed the pooled data from our phase I/II trials to determine the toxicity and efficacy of PD-1 blockade (SHR-1210)-activated MASCT (aMASCT) alone or in combination with apatinib in advanced solid tumors. METHODS: Patients with advanced solid tumors received aMASCT alone (n = 32) or aMASCT plus apatinib (500 mg q.d., n = 38) after standard treatment. The safety profile was the primary end point. The secondary end points were antitumor response, progression-free survival (PFS), and overall survival (OS). The circulating T cells were quantified before and after aMASCT infusion. RESULTS: Treatment-related adverse events (AEs) occurred in 18/32 (56.3%) and 25/38 (65.8%) patients in the aMASCT and aMASCT plus apatinib groups, respectively. No serious AEs were reported, and apatinib did not increase immunotherapy-related toxicity. The objective response rate (34.2% and 18.8%) and PFS (median 6.0 and 4.5 months, P = 0.002) were improved in the aMASCT plus apatinib group compared with the aMASCT group; however, the OS was not improved (median 10.0 and 8.2 months, P = 0.098). Multivariate analyses indicated that two or more cycles of aMASCT treatment was an independent and favorable prognostic factor of PFS and OS. The circulating T cells increased and Tregs decreased in both groups after one cycle of aMASCT treatment. CONCLUSIONS: Treatment with aMASCT plus apatinib was safe and effective for the management of advanced solid tumors.

Autophagy inhibition potentiates the anti-angiogenic property of multikinase inhibitor anlotinib through JAK2/STAT3/VEGFA signaling in non-small cell lung cancer cells.

BACKGROUND: The efficacy and safety of multikinase inhibitor anlotinib have been confirmed in the treatment of advanced non-small cell lung cancer (NSCLC). However, the direct functional mechanisms of tumor lethality mediated by anlotinib were not fully elucidated, and the underlying mechanisms related to resistance remain largely elusive. METHODS: Cell viability, colony formation, apoptosis and tumor growth assays were performed to examine the effect of anlotinib on lung cancer cells in vitro and in vivo. The punctate patterns of LC3-I/II were detected by confocal microscopy. HUVECs motility was detected using Transwell and scratch wound-healing assay. To visualize the microvessels, tubular formation assay was performed. The expression of LC3-I/II and beclin-1 and the changes of JAK2/STAT3/VEGFA pathway were detected by western blotting. The VEGFA levels in tumor supernatant were measured by ELISA. RESULTS: Anlotinib treatment decreased cell viability and induced apoptosis in Calu-1 and A549 cells. Moreover, anlotinib induced human lung cancer cell autophagy in a dose- and time-dependent manner. Blocking autophagy enhanced the cytotoxicity and anti-angiogenic ability of anlotinib as evidenced by HUVECs migration, invasion, and tubular formation assay. Co-administration of anlotinib and chloroquine (CQ) further reduced VEGFA level in the tumor supernatant, compared with that of anlotinib or CQ treatment alone. When autophagy was induced by rapamycin, the JAK2/STAT3 pathway was activated and VEGFA was elevated, which was attenuated after deactivating STAT3 by S3I-201. Further in vivo studies showed that anlotinib inhibited tumor growth, induced autophagy and suppressed JAK2/STAT3/VEGFA pathway, and CQ enhanced this effect. CONCLUSION: Anlotinib induced apoptosis and protective autophagy in human lung cancer cell lines. Autophagy inhibition further enhanced the cytotoxic effects of anlotinib, and potentiated the anti-angiogenic property of anlotinib through JAK2/STAT3/VEGFA signaling.

Apatinib combined with docetaxel as a salvage treatment for metastatic esophageal squamous cancer: a case report.

The first-line treatment for metastatic esophageal squamous cell cancer (ESCC) is a platinum- or fluorouracil-based agent, followed by later treatment with taxanes or irinotecan. However, there is still no standard third-line treatment for patients with metastatic ESCC. We present a 62-year-old man initially diagnosed with locally advanced ESCC. After esophagectomy, the patient was administrated with six cycles of docetaxel and cisplatin combined with radiotherapy. After 8.0 months, computed tomography showed the left cervical lymph node metastasis. However, the metastatic lymph node was not significantly shrunk after locally palliative radiotherapy and the patient was intolerant of irinotecan as second-line systemic therapy. Then, the patient was rechallenged with six cycles of docetaxel combined with apatinib (an oral tyrosine kinase inhibitor to vascular endothelial growth factor receptor 2 [VEGFR2]), followed by single dose of apatinib as maintenance therapy. According to the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 standard, partial response was achieved in this case after treating with docetaxel combined with apatinib. Now, the progression-free survival of this patient has been 7.5 months. After administrating with apatinib for 2 weeks, hypertension (grade III) was observed. Thus, the dose of apatinib was decreased from 850 to 500 mg and then the adverse effects were controllable and tolerable. In conclusion, apatinib with concurrent docetaxel provided potential efficacy as a salvage treatment for patients with metastatic ESCC. To our knowledge, this is the first case of ESCC who responded to apatinib combined with docetaxel.

A Pilot Study of Apatinib as Third-Line Treatment in Patients With Heavily Treated Metastatic Colorectal Cancer.

BACKGROUND: Antiangiogenic therapy has shown improved clinical outcome in metastatic colorectal cancer (mCRC). After the failure of standard treatments, regorafenib and TAS-102 would be recommended for patients with mCRC, however, they have not been approved in China during this study period. PATIENTS AND METHODS: This pilot study aimed to assess the efficacy and safety of apatinib, a novel oral inhibitor targeting vascular endothelial growth factor receptor 2, as third-line treatment for patients with mCRC refractory to standard therapies. In this retrospective study, all patients received apatinib treatment until progressive disease (PD), death, unacceptable toxicity, and curative surgery. The dose or treatment schedule was modified according to the physician's discretion according to the toxicity profiles. RESULTS: Between March 2015 and June 2017, 36 patients were enrolled and eligible for evaluation of the safety and efficacy. One patient (2.8%) achieved complete response, 3 (8.3%) achieved partial response, 24 (66.7%) achieved stable disease, and 8 (22.2%) PD. The objective response rate and the disease control rate were 11.1% (4 of 36), and 77.8% (28 of 36), respectively. Moreover, the median overall survival (OS) since the initiation of first-line treatment was 33.2 months. The median progression-free survival (PFS) and median OS from apatinib treatment were 4.8 and 10.1 months, respectively. Intergroup analysis showed that there was no significant difference in median PFS and median OS between patients who were previously treated with and without bevacizumab. The most common Grade 3 to 4 adverse reactions were hand-foot syndrome, hypertension, and proteinuria. CONCLUSION: Our results suggested that apatinib was active as a third-line treatment of refractory mCRC with a manageable tolerability profile. In addition, preliminary data suggested that the efficacy of apatinib would not be affected by previous bevacizumab treatment. Further prospective randomized controlled clinical trials are urgently needed.