Natural course of metastatic castration-resistant prostate cancer in the era of intensified androgen deprivation therapy in the hormone-sensitive setting.

BACKGROUND: Androgen deprivation therapy (ADT) intensification (ADTi) (i.e., ADT with androgen receptor pathway inhibitor or docetaxel, or both) has significantly improved survival outcomes of patients with metastatic hormone-sensitive prostate cancer (mHSPC). However, the impact of prior ADTi in the mHSPC setting on the disease presentation and survival outcomes in metastatic castration-resistant prostate cancer (mCRPC) is not well characterized. In this study, our objective was to compare the disease characteristics and survival outcomes of patients with new mCRPC with respect to receipt of intensified or nonintensified ADT in the mHSPC setting. METHODS: In this institutional review board-approved retrospective study, eligibility criteria were as follows: patients diagnosed with mCRPC, treated with an approved first-line mCRPC therapy, and who received either intensified or nonintensified ADT in the mHSPC setting. Progression-free survival (PFS) was defined from the start of first-line therapy for mCRPC to progression per Prostate Cancer Working Group 2 criteria or death, and overall survival (OS) was defined from the start of first-line therapy for mCRPC to death or censored at the last follow-up. A multivariable analysis using the Cox proportional hazards model was used, adjusting for potential confounders. RESULTS: Patients (n = 387) treated between March 20, 2008, and August 18, 2022, were eligible and included: 283 received nonintensified ADT, whereas 104 were treated with ADTi. At mCRPC diagnosis, patients in the ADTi group were significantly younger, had more visceral metastasis, lower baseline prostate-specific antigen (all p < 0.01), and lower hemoglobin (p = 0.027). Furthermore, they had significantly shorter PFS (median 4.8 vs. 8.4 months, adjusted hazard ratio [HR]: 1.46, 95% confidence interval [95% CI]: 1.07-2, p = 0.017) and OS (median 21.3 vs. 33.1 months, adjusted HR: 1.53, 95% CI: 1.06-2.21, p = 0.022) compared to patients in the nonintensified ADT group. CONCLUSION: Patients treated with ADTi in the mHSPC setting and experiencing disease progression to mCRPC had more aggressive disease features of mCRPC (characterized by a higher number of poor prognostic factors at mCRPC presentation). They also had shorter PFS on first-line mCRPC treatment and shorter OS after the onset of mCRPC compared to those not receiving ADTi in the mHSPC setting. Upon external validation, these findings may impact patient counseling, prognostication, treatment selection, and design of future clinical trials in the mCRPC setting. There remains an unmet need to develop novel life-prolonging therapies with new mechanisms of action to improve mCRPC prognosis in the current era.

Cabozantinib with immune checkpoint inhibitor versus cabozantinib monotherapy in patients with metastatic clear cell renal cell carcinoma progressing after prior immune checkpoint inhibitor.

INTRODUCTION: Rechallenge with antibodies targeting programmed cell death protein-1 or its ligand (PD-1/L1) after discontinuation or disease progression in solid tumors following a prior PD-1/L1 treatment is often practiced in clinic. This study aimed to investigate if adding PD-1/L1 inhibitors to cabozantinib, the most used second-line treatment in real-world patients with metastatic clear cell renal cell carcinoma (mccRCC), offers additional benefits. METHODS: Using de-identified patient-level data from a large real-world US-based database, patients diagnosed with mccRCC, who received any PD-1/L1-based combination in first-line (1L) setting, followed by second-line (2L) therapy with either cabozantinib alone or in combination with PD-1/L1 inhibitors were included. Patients given a cabozantinib-containing regimen in 1L were excluded. The study end points were real-world time to next therapy (rwTTNT) and real-world overall survival (rwOS) by 2L. RESULTS: Of 12,285 patients with metastatic renal cell carcinoma in the data set, 348 patients met eligibility and were included in the analysis. After propensity score matching weighting, cabozantinib with PD-1/L1 inhibitors versus cabozantinib (ref.) had similar rwTTNT and rwOS in the 2L setting. Hazard ratios and 95% confidence interval (CI) for rwTTNT and rwOS are 0.74 (95% CI, 0.49-1.12) and 1.15 (95% CI, 0.73-1.79), respectively. CONCLUSION: In this study, the results align with the phase 3 CONTACT-03 trial results, which showed no additional benefit of adding PD-L1 inhibitor to cabozantinib compared to cabozantinib alone in 2L following PD-1/L1-based therapies in 1L. These results from real-world patients strengthen the evidence regarding the futility of rechallenge with PD-1/L1 inhibitors.

Transmembrane protein 176B regulates amino acid metabolism through the PI3K-Akt-mTOR signaling pathway and promotes gastric cancer progression.

BACKGROUND: The present study aimed to investigate the expression level, biological function, and underlying mechanism of transmembrane protein 176B (TMEM176B) in gastric cancer (GC). METHODS: TMEM176B expression was detected by quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting (WB). The function of TMEM176B was determined by various in vitro assays including colony formation, 5-ethynyl-2'-deoxyuridine (EdU), Transwell, and flow cytometry. Bioinformatics techniques were then used to elucidate the signaling pathways associated with TMEM176B activity. Tumor formation experiments were conducted on nude mice for in vivo validation of the preceding findings. TMEM176B expression was cross-referenced to clinicopathological parameters and survival outcomes. RESULTS: It was observed that TMEM176B was overexpressed in GC cells and tissues. Targeted TMEM176B abrogation inhibited colony formation, proliferation, migration, and invasion but promoted apoptosis in GC cell lines while TMEM176B overexpression had the opposite effects. Subsequent experimental validation disclosed an association between TMEM176B and the phosphatidylinositol 3-carboxykinase (PI3K)-protein kinase B (Akt)-mammalian target of rapamycin (mTOR) signaling axis. Moreover, TMEM176B affects GC cancer progression by regulating asparagine synthetase (ASNS). The in vivo assays confirmed that TMEM176B is oncogenic and the clinical data revealed a connection between TMEM176B expression and the clinicopathological determinants of GC. CONCLUSION: The foregoing results suggest that TMEM176B significantly promotes the development of gastric cancer and is an independent prognostic factor of it.

Cancer-associated fibroblasts suppress ferroptosis and induce gemcitabine resistance in pancreatic cancer cells by secreting exosome-derived ACSL4-targeting miRNAs.

BACKGROUND: Pancreatic cancer continues to be one of the world's most lethal cancers. Chemotherapy resistance in patients with advanced pancreatic cancer often accompany with dismal prognosis, highlighting the need to investigate mechanisms of drug resistance and develop therapies to overcome chemoresistance. METHODS: This research was filed with the Chinese Clinical Trial Registry (ChiCTR2200061320). In order to isolate primary normal fibroblasts (NFs) and cancer-associated fibroblasts (CAFs) samples of pancreatic ductal adenocarcinoma (PDAC) and paracancerous pancreatic tissue from individuals diagnosed with PDAC were obtained. The exosomes were obtained using ultracentrifugation, and their characteristics were determined by Western blotting, nanoparticle tracking analysis, and transmission electron microscopy. CAF-derived miRNAs were analyzed by RT-qPCR and high-throughput sequencing. Gemcitabine (GEM) was employed to promote ferroptosis, and ferroptosis levels were determined by monitoring lipid reactive oxygen species (ROS), cell survival, and intracellular Fe2+ concentrations. To assess in vivo tumor response to GEM therapy, a xenograft tumor mouse model was utilized. RESULTS: Exosomes derived from CAFs in PDAC did not exhibit innate GEM resistance. CAFs promoted chemoresistance in PDAC cells following GEM treatment by secreting exosomes, and maintaining signaling communication with cancer cells. Mechanistically, miR-3173-5p derived from CAF exosomes sponged ACSL4 and inhibited ferroptosis after uptake by cancer cells. CONCLUSION: This work demonstrates a novel mode of acquired chemoresistance in PDAC and identifies the miR-3173-5p/ACSL4 pathway as a promising treatment target for GEM-resistant pancreatic cancer.

Predictors of response to neoadjuvant therapy in urothelial cancer.

Neoadjuvant cisplatin-based chemotherapy (NACC) followed by radical cystectomy is the standard treatment for localized muscle-invasive bladder cancer (MIBC). Patients who achieve a complete pathological response following NACC have better overall survival than those with residual disease. However, a subset of patients does not derive benefit from NACC while experiencing chemotherapy-related side effects that may delay cystectomy, which can be detrimental. There is a need for predictive and prognostic biomarkers to better stratify patients who will derive benefits from NACC. This review summarizes the currently available literature on various predictors of response to neoadjuvant chemotherapy. Covered predictors include clinical factors, treatment regimens (including chemotherapy and immunotherapy), histological predictors, and molecular predictors such as DNA repair genes, p53, FGFR3, ERBB2, Bcl-2, EMMPRIN, survivin, choline-phosphate cytidylyltransferase-α, epigenetic markers, immunological markers, other molecular predictors and gene expression profiling. Further, we elaborate on the potential role of neoadjuvant immunotherapy and the correlative biomarkers of response.

Differences in Tumor Gene Expression Profiles Between De Novo Metastatic Castration-sensitive Prostate Cancer and Metastatic Relapse After Prior Localized Therapy.

BACKGROUND AND OBJECTIVE: It has been reported that patients with de novo metastatic castration-sensitive prostate cancer (dn-mCSPC) have worse prognosis and outcomes than those whose cancer relapses after prior local therapy (PLT-mCSPC). Our aim was to interrogate and validate underlying differences in tumor gene expression profiles between dn-mCSPC and PLT-mCSPC. METHODS: The inclusion criteria were histologically confirmed prostate adenocarcinoma and the availability of RNA sequencing data for treatment-naïve primary prostate tissue. RNA sequencing was performed by Tempus or Caris Life Sciences, both of which have Clinical Laboratory Improvement Amendments certification. The Tempus cohort was used for interrogation, while the Caris cohort was used for validation. Differential gene expression analysis between the cohorts was conducted using the DEseq2 pipeline. The resulting gene expression profiles were further analyzed using Gene Set Enrichment software to identify pathways with enrichment in each cohort. KEY FINDINGS AND LIMITATIONS: Overall, 128 patients were eligible, of whom 78 were in the Tempus cohort (dn-mCSPC 37, PLT-mCSPC 41) and 50 were in the Caris cohort (dn-mCSPC 30, PLT-mCSPC 20). Tumor tissues from patients with dn-mCSPC had higher expression of genes associated with inflammation pathways, while tissues from patients with PLT-mCSPC had higher expression of genes involved in oxidative phosphorylation, fatty acid metabolism, and androgen response pathways. CONCLUSIONS AND CLINICAL IMPLICATIONS: Our study revealed upregulation of distinct genomic pathways in dn-mCSPC in comparison to PLT-mCSPC. These hypothesis-generating data could guide personalized therapy for men with prostate cancer and explain different survival outcomes for dn-mCSPC and PLT-mCSPC. PATIENT SUMMARY: We measured gene expression levels in tumors from patients with metastatic castration-sensitive prostate cancer. In patients with metastatic disease at first diagnosis, inflammatory pathways were upregulated. In patients whose metastasis occurred on relapse after treatment, androgen response pathways were upregulated. These findings could help in personalizing therapy for prostate cancer and explaining differences in survival.

Differential Tumor Gene Expression Profiling of Patients With Prostate Adenocarcinoma on the Basis of BMI.

PURPOSE: An increased BMI is linked to increased prostate adenocarcinoma incidence and mortality. Baseline tumor gene expression profiling (GEP) can provide a comprehensive picture of the biological processes related to treatment response and disease progression. We interrogate and validate the underlying differences in tumor GEP on the basis of BMI in patients with prostate adenocarcinoma. METHODS: The inclusion criteria consisted of histologically confirmed prostate adenocarcinoma and the availability of RNA sequencing data obtained from treatment-naïve primary prostate tissue. RNA sequencing was performed by a Clinical Laboratory Improvement Amendments-certified laboratory (Tempus or Caris Life Sciences). The Tempus cohort was used for interrogation and the Caris cohort for validation. Patients were stratified on the basis of BMI at the time of prostate cancer diagnosis: BMI-high (BMIH; BMI ≥30) and BMI-low (BMIL; BMI <30). Differential gene expression analysis between the two cohorts was conducted using the DEseq2 pipeline. The resulting GEPs were further analyzed using Gene Set Enrichment software to identify pathways that exhibited enrichment in each cohort. RESULTS: Overall, 102 patients were eligible, with 60 patients in the Tempus cohort (BMIL = 38, BMIH = 22) and 42 patients in the Caris cohort (BMIL = 24, BMIH = 18). Tumor tissues obtained from patients in the BMIL group exhibited higher expression of genes associated with inflammation pathways. BMIH displayed increased expression of genes involved in pathways such as heme metabolism and androgen response. CONCLUSION: Our study shows the upregulation of distinct genomic pathways in BMIL compared with BMIH patients with prostate cancer. These hypothesis-generating data could explain different survival outcomes in both groups and guide personalized therapy for men with prostate cancer.

Tousled-like kinase 1 promotes gastric cancer progression by regulating the tumor growth factor-beta signaling pathway.

BACKGROUND: The role of Tousled-like kinase 1 (TLK1) in in gastric cancer (GC) remains unclear. AIM: To investigate the expression, biological function, and underlying mechanisms of TLK1 in GC. METHODS: We measured TLK1 protein expression levels and localized TLK1 in GC cells and tissues by western blot and immunofluorescence, respectively. We transfected various GC cells with lentiviruses to create TLK1 overexpression and knockdown lines and established the functional roles of TLK1 through in vitro colony formation, 5-ethynyl-2`-deoxyuridine, and Transwell assays as well as flow cytometry. We applied bioinformatics to elucidate the signaling pathways associated with TLK1. We performed in vivo validation of TLK1 functions by inducing subcutaneous xenograft tumors in nude mice. RESULTS: TLK1 was significantly upregulated in GC cells and tissues compared to their normal counterparts and was localized mainly to the nucleus. TLK1 knockdown significantly decreased colony formation, proliferation, invasion, and migration but increased apoptosis in GC cells. TLK1 overexpression had the opposite effects. Bioinformatics revealed, and subsequent experiments verified, that the tumor growth factor-beta signaling pathway was implicated in TLK1-mediated GC progression. The in vivo assays confirmed that TLK1 promotes tumorigenesis in GC. CONCLUSION: The findings of the present study indicated that TLK1 plays a crucial role in GC progression and is, therefore, promising as a therapeutic target against this disease.

Stressed target cancer cells drive nongenetic reprogramming of CAR T cells and solid tumor microenvironment.

The poor efficacy of chimeric antigen receptor T-cell therapy (CAR T) for solid tumors is due to insufficient CAR T cell tumor infiltration, in vivo expansion, persistence, and effector function, as well as exhaustion, intrinsic target antigen heterogeneity or antigen loss of target cancer cells, and immunosuppressive tumor microenvironment (TME). Here we describe a broadly applicable nongenetic approach that simultaneously addresses the multiple challenges of CAR T as a therapy for solid tumors. The approach reprograms CAR T cells by exposing them to stressed target cancer cells which have been exposed to the cell stress inducer disulfiram (DSF) and copper (Cu)(DSF/Cu) plus ionizing irradiation (IR). The reprogrammed CAR T cells acquire early memory-like characteristics, potent cytotoxicity, enhanced in vivo expansion, persistence, and decreased exhaustion. Tumors stressed by DSF/Cu and IR also reprogram and reverse the immunosuppressive TME in humanized mice. The reprogrammed CAR T cells, derived from peripheral blood mononuclear cells of healthy donors or metastatic female breast cancer patients, induce robust, sustained memory and curative anti-solid tumor responses in multiple xenograft mouse models, establishing proof of concept for empowering CAR T by stressing tumor as a promising therapy for solid tumors.