Aggressive prostate cancer with somatic loss of the homologous recombination repair gene FANCA: a case report

Bridging Health Disparities: a Genomics and Transcriptomics Analysis by Race in Prostate Cancer

As the era of cancer genomics expands, disproportionate rates of prostate cancer incidence and mortality by race have demonstrated increasing relevance in clinical settings. While Black men are most particularly affected, as data has historically shown, the opposite is observed for Asian men, thus creating a basis for exploring genomic pathways potentially involved in mediating these opposing trends. Studies on racial differences are limited by sample size, but recent expanding collaborations between research institutions may improve these imbalances to enhance investigations on health disparities from the genomics front. In this study, we performed a race genomics analysis using GENIE v11, released in January 2022, to investigate mutation and copy number frequencies of select genes in both primary and metastatic patient tumor samples. Further, we investigate the TCGA race cohort to conduct an ancestry analysis and to identify differentially expressed genes highly upregulated in one race and subsequently downregulated in another. Our findings highlight pathway-oriented genetic mutation frequencies characterized by race, and further, we identify candidate gene transcripts that have differential expression between Black and Asian men.

G-protein signaling of oxytocin receptor as a potential target for cabazitaxel-resistant prostate cancer

Although the treatment armamentarium for patients with metastatic prostate cancer has improved recently, treatment options after progression on cabazitaxel (CBZ) are limited. To identify the mechanisms underlying CBZ resistance and therapeutic targets, we performed single-cell RNA sequencing of circulating tumor cells (CTCs) from patients with CBZ-resistant prostate cancer. Cells were clustered based on gene expression profiles. In silico screening was used to nominate candidate drugs for overcoming CBZ resistance in castration-resistant prostate cancer. CTCs were divided into three to four clusters, reflecting intrapatient tumor heterogeneity in refractory prostate cancer. Pathway analysis revealed that clusters in two cases showed up-regulation of the oxytocin (OXT) receptor-signaling pathway. Spatial gene expression analysis of CBZ-resistant prostate cancer tissues confirmed the heterogeneous expression of OXT-signaling molecules. Cloperastine (CLO) had significant antitumor activity against CBZ-resistant prostate cancer cells. Mass spectrometric phosphoproteome analysis revealed the suppression of OXT signaling specific to CBZ-resistant models. These results support the potential of CLO as a candidate drug for overcoming CBZ-resistant prostate cancer via the inhibition of OXT signaling.

Germline variant screening with targeted next generation sequencing in prostate cancer: phenotype-genotype correlation

BACKGROUND

Next generation sequencing provides new information about the molecular pathogenesis of cancer. We used a targeted NGS-based multiple gene panel comprising prostate cancer (PCa) predisposing genes to assess the prevalence of germline mutations in PCa patients.

METHODS

In a cohort of twenty-one PCa patients with a family history of cancer, a targeted multigene panel consisting of 39 genes associated with hereditary cancer was created and analyzed using the next generation sequencing method. The novel and pathogenic mutations detected were confirmed by Sanger sequencing method. Thereafter, the data obtained were evaluated using different genomic variant classifiers and databases.

RESULTS

With an incidence of less than 5% in different populations (MAF<0.05); a total of 81 variants were identified, including 41 missense, 16 synonymous, 3 splice-site, 11 intronic, 5 in-del and 5 novels. According to the ACMG criteria, 5 (6.2%) of these variants are pathogenic/likely pathogenic; 5 (6.2%) of them were classified as novel variants. In addition, variants having very low-frequency and unknown clinical significance (VUS) in the databases were detected.

Whole-Exome Sequencing of Rare Site Endometriosis-Associated Cancer

Malignant transformation of extraovarian endometriosis is rare, with the carcinogenesis mechanism unclear. To clarify the actionable variants of rare-site endometriosis-associated cancer (RSEAC), we performed whole-exome sequencing for the tumor, in two patients. The intestine was affected in both cases, although the histology was that of clear cell carcinoma and undifferentiated carcinoma, respectively. Therefore, the cases were referred to as endometriosis-associated intestinal tumors (EIATs). Actionable variants (all frameshift mutations) were identified in tumor suppressor genes ARID1A, PTEN, and p53; however, no oncogenic variants were identified. Both cases were microsatellite stable. The patient with undifferentiated carcinoma exhibited hypermutator and homologous recombination deficiency phenotypes. The dominant mutation signatures were signature 30 (small subset of breast cancers) and 19 (pilocytic astrocytoma) in patient 1, and signature 5 (small subset of breast cancers) and 3 (breast, ovarian, and pancreatic cancers) in patient 2. Immunohistochemistry revealed positive CD8 and PD-1 expression in both patients; patient 1 also showed positive PDL-1 expression. Our results suggest that RSEAC is associated with variants of tumor suppressor genes as epigenetic alterations. Mutation signature-based whole-exome sequencing could be useful to select an adjuvant chemotherapy regimen. High CD8 and PD-1 expression in RSEAC suggests that immune checkpoint inhibitors are useful for treatment.

Pulmonary metastasis secondary to abiraterone-resistant prostate cancer with homozygous deletions of BRCA2: First Japanese case

INTRODUCTION

Most metastatic prostate cancers acquire the capacity for androgen-independent growth and become resistant to androgen deprivation therapy. A patient-focused treatment strategy is needed for aggressive castration-resistant prostate cancer.

CASE PRESENTATION

We report the case of a 62-year-old man who presented with prostatic adenocarcinoma who was treated by radiation and combined androgen blockade. After completion of first-line therapy, he was diagnosed with multiple metastatic castration-resistant prostate cancer in the lung. Second-line therapy with abiraterone acetate resulted in partial remission of the lung metastases. Thoracic surgery was performed to remove the single lung metastasis remaining. Next-generation sequencing of the specimens demonstrated homozygous loss of BRCA2. We note in this case a heterogeneous response to abiraterone acetate may be related to the somatic BRCA2 deletions.

CONCLUSIONS

We present the first Japanese case of a metastatic abiraterone acetate-resistant castration-resistant prostate cancer accompanied by BRCA2 mutation.

A Multiple Primary Malignancy Patient With FANCA Gene Mutation: A Case Report and Literature Review

Background: Multiple primary malignancies (MPMs) refer to two or more primary malignant tumors in the same individual, the prevalence of which ranges from 0. 734 to 11.7%. The risk factors for MPMs vary and include both genetic and environmental causes. FANCA gene mutation might be a predisposition to the development of a second primary cancer. Here, we report a case in which a patient with a FANCA mutation developed thyroid papillary carcinoma and gastric adenocarcinoma.

Case Presentation: A 48-year-old woman was diagnosed with thyroid cancer underwent resection in 2006. In 2008, the patient developed gastric adenocarcinoma and underwent radical gastrectomy. Gastric cancer was completely remitted after radiochemotherapy, but metastasis developed, and she received immunotherapy. The patient died on October 27, 2019. Peripheral blood gene detection showed germline FANCA mutation.

Conclusions: Gene detection is of great importance in cancer patients, especially in those with MPMs. FANCA mutation is a predisposition to tumorigenesis that can increase the risk of developing MPMs. Patients with heterozygous FANCA gene mutations have poorer outcomes.