Neoadjuvant adebrelimab in locally advanced resectable esophageal squamous cell carcinoma: a phase 1b trial

Immune cell patterns before and after neoadjuvant immune checkpoint blockade combined with chemoradiotherapy in locally advanced esophageal squamous cell carcinoma

BACKGROUND

Neoadjuvant immune checkpoint blockade (ICB) combined with chemoradiotherapy offers high pathologic complete response (pCR) rate for patients with locally advanced esophageal squamous cell carcinomas (ESCC). But the dynamic tumor immune microenvironment modulated by such neoadjuvant therapy remains unclear.

PATIENTS AND METHODS

A total of 41 patients with locally advanced ESCC were recruited. All patients received neoadjuvant toripalimab combined with concurrent chemoradiotherapy. Matched pre- and post-treatment tissues were obtained for fluorescent multiplex immunohistochemistry (mIHC) and IHC analyses. The densities and spatial distributions of immune cells were determined by HALO modules. The differences of immune cell patterns before and after neoadjuvant treatment were investigated.

RESULTS

In the pre-treatment tissues, more stromal CD3 + FoxP3 + Tregs and CD86+/CD163 + macrophages were observed in patients with residual tumor existed in the resected lymph nodes (pN1), compared with patients with pCR. The majority of macrophages were distributed in close proximity to tumor nest in pN1 patients. In the post-treatment tissues, pCR patients had less CD86 + cell infiltration, whereas higher CD86 + cell density was significantly associated with higher tumor regression grades (TRG) in non-pCR patients. When comparing the paired pre- and post-treatment samples, heterogeneous therapy-associated immune cell patterns were found. Upon to the treatment, CD3 + T lymphocytes were slightly increased in pCR patients, but markedly decreased in non-pCR patients. In contrast, a noticeable increase and a less obvious decrease of CD86 + cell infiltration were respectively depicted in non-pCR and pCR patients. Furthermore, opposite trends of the treatment-induced alterations of CD8 + and CD15 + cell infiltrations were observed between pN0 and pN1 patients.

CONCLUSIONS

Collectively, our data demonstrate a comprehensive picture of tumor immune landscape before and after neoadjuvant ICB combined with chemoradiotherapy in ESCC. The infiltration of CD86 + macrophage may serve as an unfavorable indicator for neoadjuvant toripalimab combined with chemoradiotherapy.

PD-1/CD80+ small extracellular vesicles from immunocytes induce cold tumours featured with enhanced adaptive immunosuppression

Only a minority of cancer patients benefit from immune checkpoint blockade therapy. Sophisticated cross-talk among different immune checkpoint pathways as well as interaction pattern of immune checkpoint molecules carried on circulating small extracellular vesicles (sEV) might contribute to the low response rate. Here we demonstrate that PD-1 and CD80 carried on immunocyte-derived sEVs (I-sEV) induce an adaptive redistribution of PD-L1 in tumour cells. The resulting decreased cell membrane PD-L1 expression and increased sEV PD-L1 secretion into the circulation contribute to systemic immunosuppression. PD-1/CD80+ I-sEVs also induce downregulation of adhesion- and antigen presentation-related molecules on tumour cells and impaired immune cell infiltration, thereby converting tumours to an immunologically cold phenotype. Moreover, synchronous analysis of multiple checkpoint molecules, including PD-1, CD80 and PD-L1, on circulating sEVs distinguishes clinical responders from those patients who poorly respond to anti-PD-1 treatment. Altogether, our study shows that sEVs carry multiple inhibitory immune checkpoints proteins, which form a potentially targetable adaptive loop to suppress antitumour immunity.

Population pharmacokinetics of adebrelimab - Support of alternative flat dose regimen in extensive-stage small-cell lung cancer

Adebrelimab, a novel anti-PD-L1 antibody, has been approved by the National Medical Products Administration of China as an intravenous infusion for use in combination with carboplatin and etoposide as first-line treatment for extensive-stage small-cell lung cancer in 2023. A two-compartment model with empirical time-varying CL for adebrelimab was established based on data from 263 patients receiving body weight-based doses from two clinical studies. Significant covariate effects of baseline body weight, albumin levels, tumor size, neutrophil counts, and presence of anti-drug antibodies were identified on CL of debrelimab, none of which were clinically significant or warranted dose adjustment. The degree of decrease in CL was higher in patients who responded to treatment with adebrelimab than in non-responders. Adebrelimab exposures (AUC, Ctrough, or Cmax) were not identified as a statistically significant factor related to efficacy or safety endpoint in the exposure-response analysis. Distribution of simulated exposure metrics from the flat dose regimen (1200 mg q3w) was similar to the marketed weight-based dosing regimen (20 mg/kg q3w), supporting the alternative flat dose regimen in the clinic.

Neoadjuvant PD-1 Plus Chemotherapy for Locally Advanced Esophageal Squamous Cell Carcinoma

BACKGROUND

Clinical studies have shown that programmed cell death-1 (PD-1) inhibitors can activate T cells and inhibit cancer growth. Therefore, the use of a PD-1 inhibitor plus chemotherapy as neoadjuvant chemotherapy for locally advanced esophageal cancer is worth further exploration.

METHODS

Patients with locally advanced esophageal squamous cell carcinoma were enrolled in this study to receive two cycles of a preoperative combination of toripalimab, paclitaxel, and cisplatin. Efficacy was evaluated after two treatment cycles. The patients' postoperative pathological staging was analyzed and compared. Surgery was performed within 42 days of the start date of the last chemotherapy cycle.

RESULTS

Neoadjuvant immunochemotherapy achieved a high pathologic complete response (pCR) rate (29.0%), major pathological response rate (41.9%), and objective response rate (80.6%) and demonstrated statistically significant downstaging after neoadjuvant therapy (P < .05) with manageable treatment-related adverse effects. No significant association was found between PD-L1 level and pCR (P = .365). In addition, R0 resection was achieved in all 31 (100%) patients during surgery. For all the included patients, the one-year progression-free survival rate was 87.1% (95% CI: 75.3%-98.9%), the one-year overall survival (OS) rate was 96.8% (95% CI: 79.8%-95.9%), and the two-year OS rate was 83.9% (95% CI: 71.6%-92.2%).

CONCLUSIONS

Our findings indicate that this combination may be a potential neoadjuvant therapy regimen in this setting.

Tislelizumab with gemcitabine and cisplatin as a neoadjuvant regimen for muscle-invasive bladder cancer: case series

Introduction and importance

The feasibility of combined tislelizumab with gemcitabine and cisplatin as a neoadjuvant regimen for muscle-invasive bladder cancer (MIBC) remains to be investigated.

Case presentation

The neoadjuvant treatment not only shrunk tumours significantly but also lowered their stages from T4bN1M0, T3N0M0, and T3bN0M0 to pT1, pT0 and pTis, respectively. The treatment suppressed tumour cell proliferation and promoted luminal-to-basal transition.

Clinical discussion

MIBC is an aggressive bladder cancer with poor prognosis. All three patients with MIBC benefited greatly from the neoadjuvant regimen (tislelizumab + gemcitabine + cisplatin). It appears that the effect of the treatment is independent of the levels of programmed death-ligand 1 nor the subtype of urothelial bladder cancer.

Conclusion

Combination of tislelizumab with gemcitabine and cisplatin appeared to be a safe and efficacious neoadjuvant therapy for MIBC.

FAM107A as a tumor suppressor in esophageal squamous carcinoma inhibits growth and metastasis

BACKGROUND

Sequence similarity Family 107 member A (FAM107A) has been recognized as a tumor suppressor of various malignancies, which suppresses tumor proliferation and metastasis. Its specific role in esophageal squamous cell carcinoma (ESCC) remains unclear.

METHODS

Public datasets including Gene Expression Profiling Interactive Analysis (GEPIA) and Gene Expression Omnibus (GEO), quantitative real-time PCR (qRT-PCR), and Western blot were utilized for comparative analysis of FAM107A expression between ESCC and normal tissues. The link between FAM107A and clinicopathological features, as well as prognosis determined through χ2-test, log-rank analysis, and univariate and multivariate analyses, respectively. The impact of FAM107A on ESCC cell malignant behavior was confirmed through in vitro assays, including cell counting using the Cell Counting Kit-8 (CCK-8), clonal formation, wound healing, and transwell assays. Western blot analysis was employed to assess the effects of FAM107A on tumor epithelial-mesenchymal transition (EMT) and cell cycle-related proteins. Finally, xenograft tumors were developed to investigate the influence of FAM107A on ESCC growth in vivo.

RESULTS

FAM107A exhibited low expression in ESCC tissues. Reduced FAM107A expression was associated with a poorer prognosis and unfavorable clinicopathological characteristics, such as degree of differentiation, T-stage, and N-stage. Overexpression of FAM107A suppressed ESCC cell proliferation, invasion, migration, the EMT process, and cell cycle progression. Finally, FAM107A overexpression inhibited tumor development in vivo.

CONCLUSION

The decreased expression of FAM107A is indicative of a worse prognosis for ESCC patients. FAM107A exerts inhibitory impacts on malignant behavior and may hold promise as a therapeutic target for ESCC.