High T-cell infiltration in tumor tissue and younger age predict the response to pembrolizumab in recurrent urothelial cancer

Bladder Cancer Invading the Prostate and Penis and Multiple Bone Metastases Showing Significant Improvement after a Short-Term Pembrolizumab Therapy following Radiation and Gemcitabine and Cisplatin Therapy Leading to a Pathologically Complete Remission

A 65-year-old man was diagnosed with bladder cancer invading the prostate and penis and multiple bone metastases. He underwent palliative radiation (30 Gy/10 fr) through vertebral bones (Th3 and Th12-L5) and pelvic bones for pain control. The patient received pembrolizumab therapy after three courses of gemcitabine and cisplatin therapy. CT four weeks after starting pembrolizumab therapy showed that both the primary and metastatic lesions had notably reduced in size, and no new lesion was detected. He subsequently fell, resulting in a femoral neck pathological fracture, and underwent hemiarthroplasty. Pathological examination of the pathological fracture site revealed no residual tumor tissue.

Complete pathologic response after laparoscopic hepatectomy following treatment with nivolumab and ipilimumab for anticancer drug-resistant MSI-high colon cancer liver metastasis consisting of poorly differentiated adenocarcinoma with squamous differentiation: A case report

A 56-year-old man referred to our hospital for cecum cancer. Enhanced computed tomography (CT) found swollen reginal lymph nodes and liver metastasis. Magnetic Resonance Imaging (MRI) revealed a solitary lesion on liver (S2). We performed a laparoscopic ileocolic resection and liver partial resection. Tumor pathology showed that these tumors were moderate-differentiated adenocarcinoma (pT3N2bM1 Stage IVA). Genetic examination revealed MSI-high, KRAS wild type, and BRAF wild type. After surgery, two liver metastases were found in S4 and S7 as new lesion in EOB-MRI. We started chemotherapy with the FOLFOFIRI plus bevacizumab regimen, but two liver metastases were enlarged after six cycles of chemotherapy. As a second-line treatment, nivolumab and ipilimumab combination therapy was started. After three cycles of these therapy, both of these tumors shrinkage were observed. We performed laparoscopic liver resection. In specimens, there were no malignant cells. Pathological study revealed that in the initial surgery specimen, PD-L1 protein was detected in both primary and metastatic lesions, and HLA-DR, CK5/6 in liver. No recurrence was observed at 6 months after the surgery. In conclusion, we reported the case of anticancer drug-resistant MSI-high colon cancer liver metastasis was resected after treatment with immune-checkpoint inhibitors and a pathological complete response was found.

Dysfunction of sinus macrophages in tumor-bearing host induces resistance to immunotherapy

Sinus macrophages in draining lymph nodes (DLNs) are involved in anti-tumor immune reactions. CD169 (Sialoadhesin, Siglec-1) is expressed on sinus macrophages and is considered a surrogate marker for the immunostimulatory phenotype of macrophages. In this study, the significance of sinus macrophages in immunotherapy was evaluated using mouse models. Treatment with anti-programmed death-ligand 1 (PD-L1) antibody suppressed the subcutaneous tumor growth of MC38 and E0771 cells but was not effective against MB49 and LLC tumors. Decreased cytotoxic T-lymphocyte (CTL) infiltration in tumor tissues and CD169 expression in sinus macrophages were observed in MB49 and LLC cells compared to corresponding parameters in MC38 and E0771 cells. The anti-tumor effects of the anti-PD-L1 antibody on MC38 and E0771 cells were abolished when sinus macrophages in DLNs were depleted, suggesting that sinus macrophages are involved in the therapeutic effect of the anti-PD-L1 antibody. Naringin activated sinus macrophages. Naringin inhibited tumor growth in MB49- and LLC-bearing mice but did not affect that in MC38- and E0771-bearing mice. The infiltration of CTLs in tumor tissues and their activation were increased by naringin, and this effect was impaired when sinus macrophages were depleted. Combination therapy with naringin and anti-PD-L1 antibody suppressed MB49 tumor growth. In conclusion, CD169-positive sinus macrophages in DLNs are critical for anti-tumor immune responses, and naringin suppresses tumor growth by activating CD169-positive sinus macrophages and anti-tumor CTL responses. The activation status of sinus macrophages has been suggested to differ among tumor models, and this should be investigated in future studies.

Downregulation of PTCD1 in Bladder Urothelial Carcinoma Predicts Poor Prognosis and Levels of Immune Infiltration

Pentatricopeptide repeat domain 1 (PTCD1) was reported to regulate mitochondrial metabolism and oxidative phosphorylation. However, the effect and mechanism of PTCD1 in the development of bladder urothelial carcinoma (BLCA) remain unclear. The databases from The Cancer Genome Atlas (TCGA) and Human Protein Atlas (HPA) were used to analyze the expression changes, clinical features, and prognostic values of PTCD1. A nomogram was built to predict the prognostic outcomes of BLCA cases. The potential genes interacting with PTCD1 were explored by Weighted Gene Coexpression Network Analysis (WGCNA). The estimation of associations between PTCD1 and tumor mutations, tumor immunities, and m6A methylations was performed. The study found that the gradual decrease of PTCD1 expression was observed with the increase of stage and grade. Low PTCD1 expression was greatly correlated with higher pathological stage, N stage, and poor prognosis in TCGA cohorts; interestingly, low-grade BLCA cases all exhibited high expression of PTCD1. HPA database analysis implied that the expression of PTCD1 protein in BLCA was lower than that in normal bladder tissue, and the protein expression of PTCD1 in high-grade BLCA was lower than that in low-grade BLCA. Multivariate Cox regression analysis indicated that PTCD1 may serve as an independent factor influencing prognosis of BLCA. Mechanistically, PTCD1 played a regulatory role in BLCA progression through multiple tumor-related pathways containing PI3K-Akt signaling, ECM-receptor interaction, oxidative phosphorylation, and extracellular matrix organization. WGCNA reported that PTCD1 had a strong positive correlation with POLR2J, ZNHT1, ATP5MF, PDAP1, BUD31, and COPS6. Besides, the mRNA expression of PTCD1 was negatively associated with immune cells' infiltrations, immune functions, and checkpoints, especially with some m6A methylation regulators in BLCA. In sum, downregulation of PTCD1 expression may be involved in the development of BLCA and remarkably correlated with poor prognosis. Meantime, it showed an influence in immune cell infiltration and may serve as an agreeable prognostic indicator in BLCA.