Targeting SNCA in the treatment of malignant ascites in gastrointestinal cancer.

Peritoneal tumor dissemination and subsequent malignant tumor ascites (MTA) occur unexpectedly and repeatedly in patients with gastrointestinal (GI) cancers, and worsen quality of life and prognosis of the patients. Various treatments have been clinically developed for these patients, while most of the MTA cases are refractory to the treatments. Thus, effective treatments are urgently needed to improve the clinical outcomes. In this study, we identified α-synuclein (SNCA) as an immunological determinant of MTA progression in GI cancer through translational research using mouse tumor models and clinical specimens collected from gastric cancer patients. We found that the SNCA+ subsets were significantly increased in CD3+ T cells, CD56+ NK cells, and CD11b+ myeloid cells within MTA and peripheral blood cells (PBCs) of MTA cases, albeit almost absent in PBCs of healthy donors, and spleen of naive mice. Of note, the SNCA+ T-cell subset was rarely seen in patients that intraperitoneal lavage fluid without tumor cells was collected before surgery as a tumor-free control, suggesting a possible cancer-induced product, especially within the peritoneal cavity. In vivo treatment with anti-SNCA blocking mAb significantly induced anti-tumor effects in mouse MTA models, and synergistically improved anti-PD1 therapeutic efficacy, providing a significantly better prognosis. These suggest that SNCA is involved in severe immunosuppression in the MTA cases, and that blocking SNCA is effective in dramatically improving the immune status in the hosts. Targeting SNCA will be a promising strategy to improve clinical outcomes in the treatment of GI cancer patients, especially with MTA.

Efficacy of anti-epidermal growth factor antibody rechallenge in RAS/BRAF wild-type metastatic colorectal cancer: a multi-institutional observational study.

PURPOSE: To investigate circulating tumor DNA (ctDNA) RAS mutant (MT) incidence before salvage-line treatment and the clinicopathological features and molecular biological factors associated with the efficacy of anti-epithelial growth factor receptor (EGFR) monoclonal antibody (mAb) rechallenge for tissue RAS/BRAF wild type (WT) metastatic colorectal cancer (mCRC). METHODS: This multi-institutional retrospective observational study included 74 patients with mCRC with tissue RAS/BRAF WT refractory to first-line chemotherapy containing anti-EGFR mAb. ctDNA RAS status was assessed using the OncoBEAM™ RAS CRC Kit. We explored the clinicopathological features associated with ctDNA RAS status and the factors related to anti-EGFR mAb rechallenge efficacy in multivariate Cox proportional hazard regression. RESULTS: The incidence of RAS MT in ctDNA was 40.5% (30/74), which was associated with primary tumor resection (P = 0.016), liver metastasis (P < 0.001), and high tumor marker levels (P < 0.001). Among the 39 patients treated with anti-EGFR mAb rechallenge, those with ctDNA RAS WT showed significantly longer progression-free survival (PFS) than those with ctDNA RAS MT (median 4.1 vs. 2.7 months, hazard ratio [HR] = 0.39, P = 0.045). Patients who responded to first-line anti-EGFR mAb showed significantly longer PFS (HR = 0.21, P = 0.0026) and overall survival (OS) (HR = 0.23, P = 0.026) than those with stable disease. CONCLUSIONS: The incidence of ctDNA RAS MT mCRC was 40.5%, which was associated with liver metastases and high tumor volumes. Anti-EGFR mAb rechallenge may be effective for patients with mCRC who responded to first-line chemotherapy containing anti-EGFR mAb. No patients with RAS MT in ctDNA responded to anti-EGFR mAb rechallenge.

BRAF V600E-mutant colorectal cancer with CNS metastases treated successfully with encorafenib, binimetinib and cetuximab.

This report describes a case of BRAF V600E-mutated colorectal cancer with CNS metastases in which treatment with encorafenib, binimetinib and cetuximab was effective. There is limited information on the ability of encorafenib, binimetinib and cetuximab to enter the CNS.The patient was a 53-year-old man was diagnosed with ascending colon cancer (cT3N3M1c stage IVc). BRAF V600E mutation was confirmed. FOLFOX was started, but CNS metastases soon appeared. Encorafenib, binimetinib and cetuximab were administered and had a favorable effect on the CNS lesions. The patient initially responded well, but his disease progressed 2 months later. Further research is needed to improve management strategies for BRAF V600E-mutated colorectal cancer with CNS metastases.

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Impact of immune checkpoint inhibitors on survival outcomes in advanced gastric cancer in Japan: A real-world analysis.

BACKGROUND: Nivolumab was approved for the treatment of advanced gastric cancer in 2017 in Japan. The aim of this study was to assess the impact of nivolumab in a real-world clinical setting. METHODS: This single-institutional retrospective study included patients with advanced gastric or esophagogastric junction adenocarcinoma and a history of first-line chemotherapy with platinum-based doublet or triplet regimens between 2010 and 2020. To assess the impact of nivolumab on survival, the patients were divided based on the year of nivolumab approval into a pre-2017 (2010-2016) group and a post-2017 (2017-2020) group. RESULTS: From a total of 1918 patients, 1093 were excluded. There were 533 patients in the pre-2017 group and 292 in the post-2017 group. Immune checkpoint inhibitors were used significantly more often in the post-2017 group than in the pre-2017 group (8.6% vs. 47.9%). Median overall survival was significantly longer in the post-2017 group (16.9 vs. 13.9 months; hazard ratio [HR] 0.75, 95% confidence interval [CI] 0.63-0.90; p < 0.01). The proportion of patients transitioning to third-line treatment was higher in the post-2017 group than in the pre-2017 group (56.3% vs. 43.8%, p < 0.01). Median survival outcomes following progression on second-line treatment were significantly longer in the post-2017 group (4.3 vs. 3.2 months; HR 0.70, 95% CI 0.57-0.86; p < 0.01). CONCLUSION: The proportion of patients transitioning to third-line treatment and survival outcomes following progression on second-line treatment have improved since the approval of nivolumab. This drug might help to prolong overall survival in real-world practice.

Switching from FOLFIRI plus cetuximab to FOLFIRI plus bevacizumab based on early tumor shrinkage in RAS wild-type metastatic colorectal cancer: A phase II trial (HYBRID).

BACKGROUND: Long-term anti-EGFR antibody treatment increases the risk of severe dermatologic toxicities. This single-arm, phase II trial aimed to investigate the strategy of switching from cetuximab to bevacizumab in combination with FOLFIRI based on early tumor shrinkage (ETS) in patients with RAS wild-type metastatic colorectal cancer (mCRC). METHODS: Radiologic assessment was performed to evaluate ETS, defined as ≥20% reduction in the sum of the largest diameters of target lesions 8 weeks after the introduction of FOLFIRI plus cetuximab. ETS-negative patients switched to FOLFIRI plus bevacizumab, whereas ETS-positive patients continued FOLFIRI plus cetuximab for eight more weeks, with a switch to FOLFIRI plus bevacizumab thereafter. The primary endpoint was progression-free survival. RESULTS: This trial was prematurely terminated due to poor accrual after a total enrollment of 30 patients. In 29 eligible patients, 7 were ETS-negative and 22 were ETS-positive. Two ETS-negative patients and 17 ETS-positive patients switched to FOLFIRI plus bevacizumab 8 weeks and 16 weeks after initial FOLFIRI plus cetuximab, respectively. Median progression-free and overall survival durations were 13.4 and 34.7 months, respectively. Six (20%) patients experienced grade ≥3 paronychia, which improved to grade ≤2 by 18 weeks. Grade ≥3 acneiform rash, dry skin, and pruritus were not observed in any patients. CONCLUSIONS: Our novel treatment strategy delivered acceptable survival outcomes and reduced severe dermatologic toxicities.

CRP and soluble CTLA4 are determinants of anti-PD1 resistance in gastrointestinal cancer.

Targeting immune inhibitory checkpoint (IC) pathways have attracted great attention as a promising strategy for treating gastrointestinal (GI) cancer. However, the therapeutic efficacy is low in most cases, and little progress has been made in establishing biomarkers that predict the possible responses, and combination regimens that enhance the therapeutic efficacy. As a predictive biomarker, soluble forms of IC molecules have been recently highlighted. However, little is known about which IC molecules is most critically associated with the treatment resistance, and also about the biological and immunological roles of the IC molecules in GI cancer. In this study, we analyzed sera obtained from advanced gastric cancer patients before and one month after treatment with anti-PD1 nivolumab for soluble IC molecules by ELISA. We found that decrease of soluble CTLA4 (sCTLA4) at posttreatment were significantly associated with a better prognosis, and combination with low level of CRP at posttreatment more clearly defined anti-PD1 responders with long-term survival. Indeed, in the in vitro setting, CRP stimulation upregulated CTLA4 expression in tumor cells followed by generation of sCTLA4 that suppressed CTL induction, and simultaneously conferred high self-renewal and invasive abilities on the tumor cells accompanied by increase of EMT-related gene expressions. In the in vivo setting, CRP injection elevated sCTLA4 level in sera of mouse tumor metastasis models, leading to failure of anti-PD1 therapy. However, treatment with anti-CTLA4 mAb or a PPARγ agonist that can reduce in vivo CRP successfully elicited anti-tumor efficacy in the anti-PD1 resistant models. These suggest that targeting CRP and sCTLA4 may be a promising strategy for improving clinical outcomes in the treatments, including anti-PD1 therapy, of GI cancer.

Exploratory analysis of serum HER2 extracellular domain for HER2 positive gastric cancer treated with SOX plus trastuzumab.

BACKGROUND: The aim of this study was to explore the clinical utility of serum HER2 extracellular domain (sHER2 ECD) using data from a clinical trial evaluating trastuzumab combined S-1 plus oxaliplatin (SOX) in HER2 positive gastric cancer. METHODS: sHER2 ECD were prospectively measured at baseline and subsequent treatment courses. Based on each quantile point of baseline sHER2 ECD levels and its early changes, patients were divided into two groups and compared clinical outcomes. RESULTS: 43 patients were enrolled, and 17 patients (39.5%) were positive for baseline sHER2 ECD. Higher baseline sHER2 ECD levels tended to have lower hazard ratios (HRs). When divided into two groups by baseline sHER2 ECD of 19.1 ng/ml, median progression-free survival (PFS) and overall survival (OS) was longer in the higher group (mPFS: 16.8 vs 8.7 months, p = 0.359. mOS: 35.5 vs 20.6 months, p = 0.270), respectively. After initiation of treatment, sHER2 ECD significantly decreased up until the third cycle. Higher reduction rates of sHER2 ECD within 3 cycles also tended to have lower HRs. When divided into two groups by reduction rate of 42.5%, mPFS and mOS was longer in the higher reduced group (mPFS: 17.2 vs 8.7 months, p = 0.095. mOS: 65.0 vs 17.8 months, p = 0.047), respectively. Furthermore, higher reduction rates could surrogate higher objective response rates (ORR) (ORR: 90% vs 63.2% for 29.5%, p = 0.065. 100% vs 70% for 42.5%, p = 0.085), respectively. CONCLUSIONS: Baseline sHER2 ECD levels and its early decline may be useful biomarkers for SOX plus trastuzumab efficacy in HER2 positive gastric cancer.

A Phase II Study of FOLFIRI Plus Ziv-Aflibercept After Trifluridine/Tipiracil Plus Bevacizumab in Patients with Metastatic Colorectal Cancer: WJOG 11018G.

BACKGROUND: Non-inferiority of trifluridine/tipiracil (FTD/TPI) plus bevacizumab (BEV) to irinotecan/fluoropyrimidine plus BEV in metastatic colorectal cancer was investigated in the phase III TRUSTY study, and we conducted a phase II study of FOLFIRI (5-FU+leucovorin+irinotecan) plus zib-aflibercept (AFL) after FTD/TPI plus BEV. However, the TRUSTY study failed during the recruitment of our patients. OBJECTIVE: We present the findings of a phase II study on the efficacy of FOLFIRI plus zib-aflibercept (AFL) after FTD/TPI plus BEV, including clinical results with plasma biomarker analyses. METHODS: This was a multicenter, single-arm, phase II study in patients with metastatic colorectal cancer refractory or intolerant to oxaliplatin, fluoropyrimidine, BEV, and FTD/TPI. The primary endpoint was progression-free survival. Fifteen plasma angiogenesis-associated biomarkers were analyzed using a Luminex® multiplex assay U-kit. RESULTS: Between January 2020 and May 2022, 26 patients (median age, 68 years) from 15 sites were enrolled. The median progression-free survival was 4.9 months (85% confidence interval, 3.4 month-not estimated). The overall response and disease control rates were 8% and 62%, respectively. The median levels of vascular endothelial growth factor-A and placental growth factor, both targets of AFL, were below the measurable limit of 30 pg/mL and 16 pg/mL, respectively. Patients were divided into two groups at the median levels of baseline biomarkers. The progression-free survival did not differ between high and low expressers of placental growth factor (p = 0.7), while it tended to be shorter in those with high levels of osteopontin (p = 0.05), angiopoietin-2 (p = 0.07), and tissue inhibitor of matrix metalloproteinases-1 (p = 0.1). CONCLUSIONS: This study did not meet the primary endpoint. Hence, FOLFIRI plus AFL should not be used after FTD/TPI plus BEV for metastatic colorectal cancer. Further studies are needed to determine factors not targeted by AFL that may affect the efficacy of the treatment. CLINICAL TRIAL REGISTRATION: jRCTs041190100.

Preoperative docetaxel, cisplatin, and 5-fluorouracil for resectable locally advanced esophageal and esophagogastric junctional adenocarcinoma.

BACKGROUND: Chemotherapy consisting of 5-fluorouracil, leucovorin, oxaliplatin, and docetaxel is the standard perioperative treatment for resectable esophageal adenocarcinoma and esophagogastric junctional adenocarcinoma (EGJ-AC) in Western countries. Meanwhile, preoperative chemotherapy consisting of docetaxel, cisplatin, and 5-fluorouracil (DCF) has been developed for esophageal squamous cell carcinoma in Japan. However, there are few reports on the safety and efficacy of preoperative DCF for resectable EGJ-AC in the Japanese population. METHODS: Patients with histologically confirmed resectable EGJ-AC who received preoperative DCF (docetaxel 70 mg/m2 and cisplatin 70 mg/m2 on day 1 and continuous infusion of 5-fluorouracil 750 mg/m2/day on days 1-5 every 3 weeks with a maximum of three cycles) between January 2015 and April 2020 were retrospectively evaluated. We assessed the rates of completion of ≥ 2 courses of DCF and R0 resection, histopathological response, progression-free survival (PFS), overall survival (OS), and adverse events. RESULTS: Thirty-two patients were included. Median follow-up was 28.7 (range, 5.2-70.8) months and median age was 63 (range, 42-80) years. Twenty-one patients (66%) had a performance status of 0. The proportions of clinical stage IIA/IIB/III/IVA/IVB disease were 3%/0%/44%/44%/9%, respectively. The treatment completion rate was 84%. A histopathological response of grade 1a/1b/2/3 was obtained in 58%/26%/13%/3% of cases. Median PFS was 40.7 months (95% confidence interval 11.8-NA). Median OS was not reached (80.8% at 3 years). Grade ≥ 3 adverse events were observed in 63% of cases (neutropenia, 44%; febrile neutropenia, 13%). No treatment-related deaths occurred. CONCLUSIONS: Preoperative DCF for resectable EGJ-AC was well tolerated and has promising efficacy.

Retrospective Analysis of Definitive Chemoradiotherapy With FOLFOX in Patients With Esophageal Cancer Intolerant to Cisplatin.

BACKGROUND/AIM: Definitive chemoradiotherapy with cisplatin (CDDP) plus 5-fluorouracil is the standard treatment for locally advanced esophageal squamous cell carcinoma (LA-ESCC); however, CDDP is unsuitable for patients with cardiac and/or renal dysfunction. Based on the results of the PRODIGE5/ACCORD17 trial, 5-fluorouracil and leucovorin with oxaliplatin plus radiotherapy (FOLFOX-RT) has been recognized as a treatment option. However, the efficacy and safety of FOLFOX-RT is still unclear in Japan. PATIENTS AND METHODS: Medical records were reviewed for patients with LA-ESCC who received FOLFOX-RT between April 2019 and July 2021 at our institution. We evaluated complete response rate, progression-free survival (PFS), overall survival (OS), and adverse events. RESULTS: Fifteen patients were analyzed and median age was 72.5 years (range=51-83 years). All patients completed three courses of FOLFOX and the planned radiotherapy. The complete response rate was 40.0%. With a median follow-up of 10.6 months, the 6-month PFS rate was 63.0% (95%CI=32.3-82.8%), and the 6-month OS rate was 85.7% (95%CI=53.9-96.2%). Common adverse events were esophagitis (80.0%), leukopenia (53.3%), fatigue (53.3%), and neutropenia (46.7%). Only one patient had grade 4 esophageal perforation. CONCLUSION: FOLFOX-RT for LA-ESCC was well tolerated and could be a treatment option for CDDP-intolerant patients.