Durable response to pembrolizumab in hepatic metastasis from colonic carcinoma with Lynch syndrome: a case report.

Pembrolizumab and other immunotherapies have become central in treating metastatic colon cancer, particularly effective in patients with mismatch repair deficiencies. We report a case involving a man who initially underwent radical surgery for sigmoid colon cancer on April 27, 2011, followed by hepatic tumor resection on September 21, 2017. Post-surgery, he received eight cycles of adjuvant chemotherapy with the CAPEOX regimen and was regularly monitored through CT and MRI scans. On August 24, 2022, liver metastases were detected, and he was diagnosed with Lynch syndrome (LS) due to germline mutation in the MSH2 and EPCAM genes. He commenced treatment with 200mg of pembrolizumab intravenously every three weeks on September 2, 2022, and demonstrated a sustained response. However, after 17 cycles, he developed a treatment related adverse event (TRAE) of pancreatic endocrine dysfunction, leading to type 1 diabetes, managed with subcutaneous insulin injections. After 30 cycles of treatment, no evidence of disease was observed. This case underscores the significant clinical benefits of first-line pembrolizumab in managing hepatic metastasis in colonic carcinoma associated with LS, despite the occurrence of TRAEs. It raises critical questions regarding the optimal duration of immunotherapy following a complete or partial response and whether treatment should be discontinued upon the emergency of TRAEs. Continued research and forthcoming clinical trials with checkpoint inhibitors are expected to refine treatment protocols for LS-associated carcinoma.

PKD2 gene variants in Chinese patients with autosomal dominant polycystic kidney disease.

PKD2 gene variants account for 4.5% to 20% of patients with autosomal dominant polycystic kidney disease (ADPKD). Little is known about the clinical characteristics of PKD2 variants in Chinese patients with ADPKD. Herein, we performed a comprehensive search for variants of PKD2 gene in 44 Chinese ADPKD pedigrees and a total of 37 variants were identified. Of these 37 variants, 18 were nonsense variants, 10 frameshift variants, 4 missense variants, and 5 splice site variants. 11/37 variants were detected for the first time. The median age at diagnosis was 30.5 years, and positive family history was detected in 77.27% patients, liver cysts in 68.18%, hypertension in 45.45%, nephrolithiasis in 31.82%, macro-hematuria in 22.73%, and proteinuria in 13.63%. The level of estimated glomerular filtration rate in 8/39 patients were blow 60 ml/min/1.73m2 . 11/17 patients were classified as rapid progression by Mayo Clinic classification. The end stage renal disease (ESRD) events were reported in 9/22 pedigrees, and the presence of nephrolithiasis and macro-hematuria were significantly associated with ESRD in the pedigrees with PKD2 variants. The identified variants and clinical features will facilitate the early diagnosis and prognosis prediction in Chinese ADPKD patients with PKD2 variants.

High hsa_circ_0020123 expression indicates poor progression to non-small cell lung cancer by regulating the miR-495/HOXC9 axis.

Circular RNAs (circRNAs) belong to non-protein-coding RNAs that regulate different pathophysiological procedures. Upregulation of hsa_circ_0020123 is found in non-small cell lung cancer (NSCLC); however, its activity and functions are not clear. In this study, the results showed that hsa_circ_0020123 expression increased in both tumor tissues and NSCLC cells. A higher hsa_circ_0020123 expression also led to poor prognoses among NSCLC patients assayed via FISH. The data of FISH also confirmed that hsa_circ_0020123 primarily had a cytoplasmic location. Hsa_circ_0020123 knockdown caused a significant decrease in nude mouse xenograft growth. Bioinformatics analyses and dual luciferase reporter assays confirmed that hsa_circ_0020123 was an miR-495 sponge and that the HOXC9 gene was a miR-495 target. The miR-495 downregulation reversed cell migration and proliferation inhibition induced by hsa_circ_0020123 silencing in vitro. HOXC9 overexpression reversed miR-495-induced inhibition of cell migration and proliferation. The dual luciferase reporter assay demonstrated that hsa_circ_0020123 interacted with miR-495 by binding to the HOXC9 3'-UTR to suppresses post-transcriptional HOXC9 expression. Taken together, our study found that hsa_circ_0020123 functioned like a tumor promoter via a novel hsa_circ_0020123/miR-495/HOXC9 axis, highlighting its possibility as a new NSCLC therapeutic target.

Detection of exosomal tyrosine receptor kinase B as a potential biomarker in ovarian cancer.

Ovarian cancer (OC) is a lethal disease diagnosed at advanced stages due to the lack of specific biomarkers. Tyrosine receptor kinase B (TrkB), which has recently been found to be related to OC progression, represents a promising potential biomarker for OC diagnosis and prognosis. The discovery of circulating exosomes as biomarkers for various diseases led us to explore exosomal TrkB in OC. Our previous study proved that the expression of TrkB was elevated in OC tissues. In this study, we focused on the detection of exosomal TrkB in OC. Exosomes were first gathered from three different OC cell lines' conditioned medium, serum samples of patients with OC as well as xenograft mice serum by serial centrifugation method. Then, we identified exosomes by transmission electron microscopy, NanoSight analysis, and expression of typical exosomal protein markers. The existence of TrkB in exosomes was measured by Western blot analysis, and the expression was detected by enzyme-linked immunosorbent assay. In this study, we demonstrated that exosomes could derive from OC cell lines, serum from OC xenograft nude mice, and clinical patients. Our study shows that serum exosomal TrkB may be considered a minimally invasive biomarker for OC.