CD38 in Advanced Prostate Cancers.

BACKGROUND: CD38, a druggable ectoenzyme, is involved in the generation of adenosine, which is implicated in tumour immune evasion. Its expression and role in prostate tumour-infiltrating immune cells (TIICs) have not been elucidated. OBJECTIVE: To characterise CD38 expression on prostate cancer (PC) epithelial cells and TIICs, and to associate this expression with clinical outcomes. DESIGN, SETTING, AND PARTICIPANTS: RNAseq from 159 patients with metastatic castration-resistant prostate cancer (mCRPC) in the International Stand Up To Cancer/Prostate Cancer Foundation (SU2C/PCF) cohort and 171 mCRPC samples taken from 63 patients in the Fred Hutchinson Cancer Research Centre cohort were analysed. CD38 expression was immunohistochemically scored by a validated assay on 51 castration-resistant PC (CRPC) and matching, same-patient castration-sensitive PC (CSPC) biopsies obtained between 2016 and 2018, and was associated with retrospectively collected clinical data. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: mCRPC transcriptomes were analysed for associations between CD38 expression and gene expression signatures. Multiplex immunofluorescence determined CD38 expression in PC biopsies. Differences in CD38+ TIIC densities between CSPC and CRPC biopsies were analysed using a negative binomial mixed model. Differences in the proportions of CD38+ epithelial cells between non-matched benign prostatic epithelium and PC were compared using Fisher's exact test. Differences in the proportions of biopsies containing CD38+ tumour epithelial cells between matched CSPC and CRPC biopsies were compared by McNemar's test. Univariable and multivariable survival analyses were performed using Cox regression models. RESULTS AND LIMITATIONS: CD38 mRNA expression in mCRPC was most significantly associated with upregulated immune signalling pathways. CD38 mRNA expression was associated with interleukin (IL)-12, IL-23, and IL-27 signalling signatures as well as immunosuppressive adenosine signalling and T cell exhaustion signatures. CD38 protein was frequently expressed on phenotypically diverse TIICs including B cells and myeloid cells, but largely absent from tumour epithelial cells. CD38+ TIIC density increased with progression to CRPC and was independently associated with worse overall survival. Future studies are required to dissect TIIC CD38 function. CONCLUSIONS: CD38+ prostate TIICs associate with worse survival and immunosuppressive mechanisms. The role of CD38 in PC progression warrants investigation as insights into its functions may provide rationale for CD38 targeting in lethal PC. PATIENT SUMMARY: CD38 is expressed on the surface of white blood cells surrounding PC cells. These cells may impact PC growth and treatment resistance. Patients with PC with more CD38-expressing white blood cells are more likely to die earlier.

Clinical Utility of Circulating Tumour Cell Androgen Receptor Splice Variant-7 Status in Metastatic Castration-resistant Prostate Cancer.

BACKGROUND: Detection of androgen receptor splice variant-7 (AR-V7) mRNA in circulating tumour cells (CTCs) is associated with worse outcome in metastatic castration-resistant prostate cancer (mCRPC). However, studies rarely report comparisons with CTC counts and biopsy AR-V7 protein expression. OBJECTIVE: To determine the reproducibility of AdnaTest CTC AR-V7 testing, and associations with clinical characteristics, CellSearch CTC counts, tumour biopsy AR-V7 protein expression and overall survival (OS). DESIGN, SETTING, AND PARTICIPANTS: CTC AR-V7 status was determined for 227 peripheral blood samples, from 181 mCRPC patients with CTC counts (202 samples; 136 patients) and matched mCRPC biopsies (65 samples; 58 patients). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: CTC AR-V7 status was associated with clinical characteristics, CTC counts, and tissue biopsy AR-V7 protein expression. The association of CTC AR-V7 status and other baseline variables with OS was determined. RESULTS AND LIMITATIONS: Of the samples, 35% were CTC+/AR-V7+. CTC+/AR-V7+ samples had higher CellSearch CTC counts (median CTC; interquartile range [IQR]: 60, 19-184 vs 9, 2-64; Mann-Whitney test p<0.001) and biopsy AR-V7 protein expression (median H-score, IQR: 100, 63-148 vs 15, 0-113; Mann-Whitney test p=0.004) than CTC+/AR-V7- samples. However, both CTC- (63%) and CTC+/AR-V7- (62%) patients had detectable AR-V7 protein in contemporaneous biopsies. After accounting for baseline characteristics, there was shorter OS in CTC+/AR-V7+ patients than in CTC- patients (hazard ratio [HR] 2.13; 95% confidence interval [CI] 1.23-3.71; p=0.02); surprisingly, there was no evidence that CTC+/AR-V7+ patients had worse OS than CTC+/AR-V7- patients (HR 1.26; 95% CI 0.73-2.17; p=0.4). A limitation of this study was the heterogeneity of treatment received. CONCLUSIONS: Studies reporting the prognostic relevance of CTC AR-V7 status must account for CTC counts. Discordant CTC AR-V7 results and AR-V7 protein expression in matched, same-patient biopsies are reported. PATIENT SUMMARY: Liquid biopsies that determine circulating tumour cell androgen receptor splice variant-7 status have the potential to impact treatment decisions in metastatic castration-resistant prostate cancer patients. Robust clinical qualification of these assays is required before their routine use.

Genomic Analysis of Three Metastatic Prostate Cancer Patients with Exceptional Responses to Carboplatin Indicating Different Types of DNA Repair Deficiency.

Platinum-based regimens have not been proved to increase survival from advanced prostate cancer (PCa). Incontrovertible evidence that a proportion of prostate cancers have homologous recombination DNA (HRD) repair defects, and that such genomic aberrations are synthetically lethal with both poly(ADP)-ribose polymerase inhibition and platinum, has increased interest in the utilisation of these drugs against a subset of these diseases. Here in we report three patients with advanced castration-resistant PCa with HRD defects having exceptional responses to carboplatin.

A nomogram to predict 5-fluorouracil toxicity: when pharmacogenomics meets the patient.

Fluoropyrimidines combined with other agents are commonly used for gastrointestinal cancer treatment. Considering that severe toxicities occur in 30% of patients, we aimed to structure a nomogram to predict toxicity, based on metabolic parameter and patients' characteristics. We retrospectively enrolled patients affected by gastrointestinal tract cancers. Pretreatment 5-fluorouracil (5-FU) degradation rate and DPYD, TSER, MTHFR A1298T, and C677T gene polymorphisms were characterized. Data on toxicities were collected according to CTCAE v3.0. Multivariate logistic regression analysis was used to structure a nomogram. 642 patients were enrolled (384 men; 258 female; median age: 67 years, range: 27-87): 449 (69.9%) patients were affected by colorectal cancer; 118 (18.4%) by gastroesophageal cancer; 66 (10.3%) by pancreatic cancer; and nine (1.4%) by other cancers. Grade 3-4 toxicities were observed in 118 (18.4%) patients and were most frequently observed in patients with altered 5-FU degradation rate (43.5 and 26.7% of the patients in the poor metabolizer and in the ultrarapid metabolizer group respectively, vs. 17% in the normal metabolizer group) and in DPYD heterozygous mutated patients (83.3% of the patients). Age, DPYD status, the number of drugs administered, and 5-FU degradation rate value were associated to severe toxicities. On the basis of these findings, we structured a nomogram to assess a score to predict the risk of developing severe toxicity. Compared with the available pharmacogenetic tests, this approach can be applied to the whole population, predicting the risk for severe toxicity, with an easy, low-cost, and not invasive technique.

5-Fluorouracil degradation rate could predict toxicity in stages II-III colorectal cancer patients undergoing adjuvant FOLFOX.

5-Fluorouracil is commonly used for gastrointestinal cancer treatment in an adjuvant setting; however, the toxicity can lead to a reduction, delay, or discontinuation of treatment. We retrospectively investigated the association between the 5-fluorouracil degradation rate (5-FUDR) and genetic polymorphisms of TSER, DPYD, and MHTFR with toxicity in colorectal cancer patients treated with adjuvant FOLFOX. Pretreatment 5-FUDR and MTHFR A1298T or C677T, TSER, and DPYD gene polymorphisms were characterized in stages II-III colorectal cancer patients. Patients were classified into three metabolic classes according to the 5-FUDR value. Association with toxicities was evaluated retrospectively using logistic regression analysis. Overall, 126 patients were selected (35 women, 91 men). Seven patients were poor metabolizers, 116 patients were normal metabolizers and three patients were ultra-rapid metabolizers. The median 5-FUDR was 1.53 ng/ml/10 cells/min (range: 0.42-2.57 ng/ml/10 cells/min). Severe, rate-limiting toxicities (grades 3-4) were encountered in 22.2% of patients. No associations between MTHFR or TSER polymorphisms and toxicity were detected, whereas 5-FUDR showed a statistically significant association with toxicity (P=0.0047). The DPYD heterozygous mutation was detected in only one patient, who showed grade 4 hematological toxicity and a lower 5-FUDR value. The 5-FUDR value seems not to be affected by MTHFR and TSER polymorphisms. Compared with the available pharmacogenomics tests, the pretreatment evaluation of 5-FUDR increases the proportion of identified colorectal patients at high risk for severe toxicity. Thus, it appears to be a suitable pretreatment toxicity biomarker in a subgroup of patients in whom dose-intensity maintenance is the key factor.

Cisplatin and 5-fluorouracil in inoperable, stage IV squamous cell carcinoma of the penis.

UNLABELLED: What's known on the subject? and What does the study add? Metastatic or locally advanced squamous cell carcinoma of the penis (SCCP) is generally incurable, but it can be palliated with systemic chemotherapy. Two retrospective studies, involving <10 patients each, showed that cisplatin plus continuous infusion of 5-fluorouracil (5-FU) may be effective and well tolerated. Cisplatin, methotrexate and bleomycin, cisplatin and irinotecan and taxanes can also play an important role for patients with locally advanced/metastatic SCCP. Finally, anti-EGFR therapy may also be effective in advanced SCCP. Although cisplatin plus continuous infusion of 5-FU is widely used in clinical practice for palliation of SCCP, toxicity and efficacy data regarding this schedule include a total of 14 patients with SCCP, treated more than two decades ago. In our retrospective study, cisplatin plus continuous infusion of 5-FU was used for palliative purposes in a homogenous sample of 25 patients with SCCP. Partial responses and stable disease were observed in 8 (32%) and 10 (40%) patients, respectively, with a median progression-free survival of 20 weeks. Neutropenia was the most important grade 3-4 side effect observed, occurring in 20% of patients. These data provide confirmation that such a combination regimen is moderately effective and well tolerated in patients with SCCP. OBJECTIVE: • To investigate the activity and toxicity of 5-fluorouracil (5-FU) as a first-line treatment in metastatic squamous cell carcinoma of the penis (SCCP). METHODS: • The medical records of 78 patients with SCCP treated between January 2000 and June 2011 at the four participating centres were reviewed. • Data regarding patients treated with first-line 5-FU were extracted. • Patients were included in the study if radiological reports were available for determination of response and progression-free survival (PFS) according to response evaluation criteria in solid tumours (RECIST) 1.1. RESULTS: • Between January 2000 and June 2011, 25 patients were treated with i.v. cisplatin on day 1 followed by 5-FU as a continuous 24-h infusion for 4 days every 3 weeks until disease progression or unacceptable toxicity. Partial responses and stable disease were observed in eight (32%) and 10 (40%) patients, respectively, with a disease control rate of 72%. • Severe neutropenia was the most important grade 3-4 side effect observed, occurring in 20% of patients. • The median (interquartile range [IQR]) PFS was 20 (11-20) weeks and the median (IQR) overall survival (OS) was 8 (7-12) months. CONCLUSION: • 5-FU is associated with a moderate response rate and is well tolerated in patients with metastatic SCCP.