Consequences of Discontinuing a 4/6 Cyclin D-Dependent Kinase Inhibitor During Endocrine Treatment in Hormone-Sensitive Metastatic Breast Cancer Patients in the Context of the COVID-19 Outbreak.

BACKGROUND: The impact of some hasty medical decision made during the first wave of the Coronavirus Disease 2019 (COVID-19) remains unknown. We have evaluated the consequences of one of these precautionary measures: the withdrawal of the cyclin D-dependent kinases 4/6 inhibitor (CDK4/6i) in patients whose metastatic disease was controlled by a combination of endocrine treatment and CDK 4/6i. METHOD: This study was noninterventional, retrospective, multicentric, and included 60 patients with HR+ HER2- metastatic disease. Their disease was controlled with the combination of endocrine treatment and CDK 4/6i. The CDK 4/6i was stopped for two months during the first COVID-19 outbreak. A univariate analysis was performed to assess the risk factors associated with disease progression. RESULTS: During this therapeutic break, 22 (37 %) patients had a radiological and/or clinical disease progression. Among them, the CDK 4/6i was re-introduced to 16 patients (n = 16/22; 73 %). A new line of treatment (chemotherapy or targeted therapy) was initiated due to the rapid symptomatic tumor progression in four patients (n = 4/22; 18 %). Two patients (n = 2/22) died in visceral crisis before another anti-tumoral treatment was introduced. In univariate analysis, the presence of liver metastases increased the risk of metastatic disease progression during the withdrawal of the CDK 4/6 (OR = 6.6; 95 % CI 1.87-23.22; P= .0033). CONCLUSION: Progression was observed in 37% of patients during the two-month treatment interruption of the CDK 4/6i. A prolonged CDK 4/6i treatment interruption in patients with clinical benefit on endocrine treatment does not seem to be a reasonable option in light of these results.

COVID-19 in Patients with Cancer: A Retrospective Study of 212 Cases from a French SARS-CoV-2 Cluster During the First Wave of the COVID-19 Pandemic.

We describe a large series of patients with solid tumors in an early COVID-19 cluster in the eastern part of France. From February to May 2020, this multicenter retrospective study enrolled 212 patients with cancer under treatment or on follow-up for any type of malignant solid tumor and positive for SARS-CoV-2. The mortality rate was 30%. Patients with gastrointestinal cancers were identified as a subset of more vulnerable patients; immunotherapy and radiotherapy within 3 months from COVID-19 diagnosis were risk factors for death. The reported data support the essential need to be proactive and weigh the risks of morbidity from COVID-19 against the magnitude of benefits of intended cancer therapies during this pandemic. IMPLICATIONS FOR PRACTICE: This article supports the essential need to be proactive (treatment delay or modification) in oncology in the setting of pandemic. This study identified patients with gastrointestinal cancers as a more vulnerable subset of patients with cancer and found that immunotherapy and radiotherapy within 3 months from COVID-19 diagnosis to be risk factors for death. The reported data indicate the necessity of weighing the risks of morbidity from COVID-19 against the magnitude of benefits of intended cancer therapies in any future wave of COVID-19.

Metabolic Response to BRAF-MEK Combination Therapy in Cecal Neuroendocrine Carcinoma With BRAFV600E Mutation and Refractory Lactic Acidosis.

We report the results of serial F-FDG PET/CT investigations in a 49-year-old woman presenting with an advanced cecal high-grade neuroendocrine carcinoma harboring a somatic BRAF mutation. Patient was refractory to standard chemotherapy regimen showing life-threatening hyperlactatemia. Early after the beginning of BRAF-MEK therapy (dabrafenib and trametinib), impressive improvement in PET/CT imaging was achieved. The pathological F-FDG uptake in cecal primary tumor as well as in nodal, hepatic, and bone metastases drastically decreased. Moreover, the reduction of total lesion glycolysis on PET/CT images was strictly related to extraordinary patient clinical response and lactic acid level normalization.

Dual effects of constitutively active androgen receptor and full-length androgen receptor for N-cadherin regulation in prostate cancer.

Constitutively active androgen receptor (AR) variants have been involved in the expression of mesenchymal markers such as N-cadherin in prostate cancer (PCa). However, the underlying molecular mechanisms remain elusive. It remains unclear, whether N-cadherin gene (CDH2) is a direct transcriptional target of AR variants or whether the observed upregulation is due to indirect effects through additional regulatory factors. Moreover, the specific contribution of full-length AR and AR variants in N-cadherin regulation in PCa has never been explored deeply. To investigate this, we artificially mimicked the co-expression of AR variants together with a full-length AR and performed miRNA-seq, RNA-seq and ChIP assays. Our results were in favor of a direct AR variants action on CDH2. Our data also revealed a distinctive mode of action between full-length AR and AR variants to regulate N-cadherin expression. Both wild type AR and AR variants could interact with a regulatory element in intron 1 of CDH2. However, a higher histone H4 acetylation in this genomic region was only observed with AR variants. This suggests that full-length AR may play an occluding function to impede CDH2 upregulation. Our data further highlighted a negative effect of AR variants on the expression of the endogenous full-length AR in LNCaP. These differences in the mode of action of AR variants and full-length AR for the control of one key gene for prostate cancer progression could be worth considering for targeting AR variants in PCa.

[Androgen receptor variants in prostate cancer]. / Variants du récepteur des androgènes dans le cancer de la prostate.

Prostate cancer is a public health concern as it currently represents the most frequent malignancy in men in Europe. Progression of this hormone-dependent cancer is driven by androgens. Thus, the most common treatment for patients with advanced prostate cancer consists in an androgen ablation by castration therapy. However, the majority of patients relapses and develops a castration-resistant prostate cancer. This failure of androgen deprivation is related to the emergence of mutant and splice variants of the androgen receptor. Indeed, androgen receptor variants are ligand-independent, constitutively active and thus able to induce resistance to castration. This review focuses on AR variants signaling pathways and their role in resistance to castration and prostate cancer progression.