Impact of BRCA1/2 gene mutations on survival of patients with pancreatic cancer: A case-series analysis

BRCA 1/2 Germline Mutation Predicts the Treatment Response of FOLFIRINOX with Pancreatic Ductal Adenocarcinoma in Korean Patients

We evaluated the proportion of BRCA 1/2 germline mutations in Korean patients with sporadic pancreatic ductal adenocarcinoma (PDAC) and its effect on the chemotherapeutic response of FOLFIRINOX. This retrospective study included patients who were treated at two tertiary hospitals between 2012 and 2020, were pathologically confirmed to have PDAC, and had undergone targeted next-generation sequencing-based germline genetic testing. Sixty-six patients were included in the study (24 men; median age 57.5 years). In the germline test, BRCA 1/2 pathogenic mutations were found in nine patients (9/66, 13%, BRCA 1, n = 3; BRCA 2, n = 5; and BRCA 1/2, n = 1). There was no significant difference in the baseline characteristics according to BRCA mutation positivity. Among patients who underwent FOLFIRINOX chemotherapy, patients with a BRCA 1/2 mutation showed a higher overall response rate than those without a BRCA 1/2 mutation (71.4% vs. 13.9%, p = 0.004). Patients with a germline BRCA 1/2 mutation showed longer progression-free survival than those without a BRCA 1/2 mutation, without a significant time difference (18 months vs. 10 months, p = 0.297). Patients with a BRCA 1/2 mutation in the germline blood test had a higher response rate to FOLFIRINOX chemotherapy in PDAC. The high proportion of BRCA 1/2 germline mutations and response rate supports the need for germline testing in order to predict better treatment response.

Targeted Sequencing Revealed Distinct Mutational Profiles of Ocular and Extraocular Sebaceous Carcinomas

The biological behavior of sebaceous carcinoma (SeC) is relatively indolent; however, local invasion or distant metastasis is sometimes reported. Nevertheless, a lack of understanding of the genetic background of SeC makes it difficult to apply effective systemic therapy. This study was designed to investigate major genetic alterations in SeCs in Korean patients. A total of 29 samples, including 20 ocular SeCs (SeC-Os) and 9 extraocular SeCs (SeC-EOs), were examined. Targeted next-generation sequencing tests including 171 cancer-related genes were performed. TP53 and PIK3CA genes were frequently mutated in both SeC-Os and SeC-EOs with slight predominance in SeC-Os, whereas the NOTCH1 gene was more commonly mutated in SeC-EOs. In clinical correlation, mutations in RUNX1 and ATM were associated with development of distant metastases, and alterations in MSH6 and BRCA1 were associated with inferior progression-free survival (all p < 0.05). In conclusion, our study revealed distinct genetic alterations between SeC-Os and SeC-EOs and some important prognostic molecular markers. Mutations in potentially actionable genes, including EGFR, ERBB2, and mismatch repair genes, were noted, suggesting consideration of a clinical trial in intractable cases.

Excision Repair Cross-Complementation Group 6 Gene Polymorphism Is Associated with the Response to FOLFIRINOX Chemotherapy in Asian Patients with Pancreatic Cancer

Simple Summary

FOLFIRINOX is a platinum-based chemotherapy regimen for patients with pancreatic cancer and is known to be more effective in the presence of the BRCA mutation, one of the DNA damage repair (DDR) gene mutations. However, BRCA mutations are less common in pancreatic cancer patients, accounting for only about 5% of cases worldwide, and are known to be even rarer in Asians. Therefore, this study aimed to uncover new genetic variants of DDR genes related to the response of FOLFIRINOX by analyzing variants of DDR genes using whole exome sequencing. Multivariable Cox regression analysis adjusted for clinical variables showed that a single nucleotide polymorphism (SNP) of the ERCC6 gene is an independent predictor for progression-free survival. If validated, the ERCC6 SNP found in this study could be used as a biomarker to predict responses to FOLFIRINOX.

Abstract

FOLFIRINOX is currently one of the standard chemotherapy regimens for pancreatic cancer patients, but little is known about the factors that can predict a response to it. We performed a study to discover novel DNA damage repair (DDR) gene variants associated with the response to FOLFIRINOX chemotherapy in patients with pancreatic cancer. We queried a cohort of pancreatic cancer patients who received FOLFIRINOX chemotherapy as the first treatment and who had tissue obtained through an endoscopic ultrasound-guided biopsy that was suitable for DNA sequencing. We explored variants of 148 DDR genes based on whole exome sequencing and performed multivariate Cox regression to find genetic variants associated with progression-free survival (PFS). Overall, 103 patients were included. Among 2384 variants of 141 DDR genes, 612 non-synonymous variants of 123 genes were selected for Cox regression analysis. The multivariate Cox model showed that rs2228528 in ERCC6 was significantly associated with improved PFS (hazard ratio 0.54, p = 0.001). The median PFS was significantly longer in patients with rs2228528 genotype AA vs. genotype GA and GG (23.5 vs. 16.2 and 8.6 months; log-rank p < 0.001). This study suggests that rs2228528 in ERCC6 could be a potential predictor of response to FOLFIRINOX chemotherapy in patients with pancreatic cancer.

Pathological complete response after neoadjuvant therapy for pancreatic ductal adenocarcinoma does not equal cure

BACKGROUND

There is a scarcity of data about patients with pancreatic ductal adenocarcinoma (PDAC) who received neoadjuvant therapy before radical resection and achieved a pathological complete response (pCR). The aim of this study was to describe the recurrence and survival in this subset of patients.

METHODS

The Embase, Web of Science and PubMed databases were systematically searched for eligible studies published between January 2000 and August 2020. Clinicopathological data of individual patients with pCR after neoadjuvant therapy for PDAC were extracted, pooled and analysed.

RESULTS

A total of 87 patients were subject to analysis. The majority of patients were female (61.5%) with a median age of 64 (range 43-75) years. Among reported, 41.9% of patients received gemcitabine-based neoadjuvant chemotherapy, 33.7% received FOLFIRINOX (5-fluorouracil, oxaliplatin, irinotecan and leucovorin)-based regimen and 24.4% received fluoropyrimidine drugs-based regimen. Preoperative radiation was administered to 78.8% of the patients. Twenty-nine (33.3%) patients developed disease recurrence during a median follow-up period of 22.4 (range 2-194) months. The median, 1-, 3- and 5-year overall survival rates were 105 months, 93.6%, 70.3% and 70.3%, respectively.

CONCLUSION

Despite the excellent long-term outcomes, a pCR does not equal cure because this cohort of patients still has a significant risk of recurrence.

Serum N-Glycome analysis reveals pancreatic cancer disease signatures

Background &Aims

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer type with loco‐regional spread that makes the tumor surgically unresectable. Novel diagnostic tools are needed to improve detection of PDAC and increase patient survival. In this study we explore serum protein N‐glycan profiles from PDAC patients with regard to their applicability to serve as a disease biomarker panel.

Methods

Total serum N‐glycome analysis was applied to a discovery set (86 PDAC cases/84 controls) followed by independent validation (26 cases/26 controls) using in‐house collected serum specimens. Protein N‐glycan profiles were obtained using ultrahigh resolution mass spectrometry and included linkage‐specific sialic acid information. N‐glycans were relatively quantified and case‐control classification performance was evaluated based on glycosylation traits such as branching, fucosylation, and sialylation.

Results

In PDAC patients a higher level of branching (OR 6.19, P‐value 9.21 × 10⁻¹¹) and (antenna)fucosylation (OR 13.27, P‐value 2.31 × 10⁻⁹) of N‐glycans was found. Furthermore, the ratio of α2,6‐ vs α2,3‐linked sialylation was higher in patients compared to healthy controls. A classification model built with three glycosylation traits was used for discovery (AUC 0.88) and independent validation (AUC 0.81), with sensitivity and specificity values of 0.85 and 0.71 for the discovery set and 0.75 and 0.72 for the validation set.

Conclusion

Serum N‐glycome analysis revealed glycosylation differences that allow classification of PDAC patients from healthy controls. It was demonstrated that glycosylation traits rather than single N‐glycan structures obtained in this clinical glycomics study can serve as a basis for further development of a blood‐based diagnostic test.

Preparation of Biodegradable Polymeric Nanocapsules for Treatment of Malignant Tumor Using Coaxial Capillary Microfluidic Device

Objective: Nanocapsules play a role in the targeted delivery of chemotherapy drugs. However, the traditional technology for preparation of nanocapsules is relatively complex with poor controllability, leading to large differences batch to batch. This study aimed to evaluate the quality of drugs-loaded nanocapsules (Drugs-NCs) fabricated by coaxial capillary microfluidic device, and inhibitory effect on malignant tumors. Materials and Methods: In this study, oxaliplatin, irinotecan, and 5-fluorouracil were selected as chemotherapy drugs, and Drugs-NCs were prepared by coaxial glass capillary microfluidic device. Next, transmission electron microscope was utilized to characterize surface morphology and particle size distribution of Drugs-NCs. Then, high performance liquid chromatography was used to determine the drug loading and encapsulation efficiency. Dialysis method was performed to measure the drug release of Drugs-NCs in vitro. To study the effects of Drugs + NCs on tumor growth in vivo, BALB/c (nu/nu) nude mice were used in vivo experiments. Results: The Drugs-NCs were spherical and uniform in size (103.4 nm). Besides, the encapsulation efficiencies of oxaliplatin, irinotecan, and 5-fluorouracil were 97.0%, 95.7%, and 15.6%, respectively. Moreover, drugs encapsulated in the nanocapsules released less and was pH-dependent, with more rapid release being observed at pH 5.5 group compared with pH 7.4 group. MTT assay and in vivo experiments indicated the inhibitory effect of Drugs-NCs on malignant tumors. Conclusion: The prepared nanocapsules had potential tumor targeting. Furthermore, coaxial capillary microfluidic device could be used as a promising microfluidic technology to fabricate multiple Drug-NCs.