Growth of prostate cancer cells is dependent upon androgen stimulation of the androgen receptor (AR). Dihydrotestosterone (DHT), the most potent androgen, is usually synthesized in the prostate from ...testosterone secreted by the testis. Following chemical or surgical castration, prostate cancers usually shrink owing to testosterone deprivation. However, tumors often recur, forming castration-resistant prostate cancer (CRPC). Here, we show that CRPC sometimes expresses a gain-of-stability mutation that leads to a gain-of-function in 3β-hydroxysteroid dehydrogenase type 1 (3βHSD1), which catalyzes the initial rate-limiting step in conversion of the adrenal-derived steroid dehydroepiandrosterone to DHT. The mutation (N367T) does not affect catalytic function, but it renders the enzyme resistant to ubiquitination and degradation, leading to profound accumulation. Whereas dehydroepiandrosterone conversion to DHT is usually very limited, expression of 367T accelerates this conversion and provides the DHT necessary to activate the AR. We suggest that 3βHSD1 is a valid target for the treatment of CRPC.
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•3βHSD1 catalyzes a rate-limiting step for DHT synthesis in CRPC•Selection for N367T mutant 3βHSD1 occurs in human CRPC tumors•The N367T 3βHSD1 mutation confers resistance to ubiquitination and degradation•Mutant 3βHSD1 protein accumulates, increasing DHT synthesis and causing CRPC
Dihydrotestosterone (DHT), a potent androgen secreted by the testis, promotes the development of prostate cancer. Castration limits tumor growth, but castration-resistant tumors often recur. A gain-of-stability mutation in the enzyme 3βHSD1, an upstream regulator of DHT biosynthesis, drives this resistance and may be a valid therapeutic target.
is both the most frequently altered gene in primary prostate cancer and a critical factor enabling cellular infection by coronaviruses, including SARS-CoV-2. The modulation of its expression by sex ...steroids could contribute to the male predominance of severe infections, and given that
has no known indispensable functions, and inhibitors are available, it is an appealing target for prevention or treatment of respiratory viral infections.
The type II transmembrane serine proteases TMPRSS2 and HAT activate influenza viruses and the SARS-coronavirus (TMPRSS2) in cell culture and may play an important role in viral spread and ...pathogenesis in the infected host. However, it is at present largely unclear to what extent these proteases are expressed in viral target cells in human tissues. Here, we show that both HAT and TMPRSS2 are coexpressed with 2,6-linked sialic acids, the major receptor determinant of human influenza viruses, throughout the human respiratory tract. Similarly, coexpression of ACE2, the SARS-coronavirus receptor, and TMPRSS2 was frequently found in the upper and lower aerodigestive tract, with the exception of the vocal folds, epiglottis and trachea. Finally, activation of influenza virus was conserved between human, avian and porcine TMPRSS2, suggesting that this protease might activate influenza virus in reservoir-, intermediate- and human hosts. In sum, our results show that TMPRSS2 and HAT are expressed by important influenza and SARS-coronavirus target cells and could thus support viral spread in the human host.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract Understanding the molecular underpinnings of sensitivity to specific therapies will advance the goal of precision medicine in prostate cancer (PCa). We identified three patients with ...metastatic castration-resistant PCa (mCRPC) who achieved an exceptional response to platinum chemotherapy (not first-line treatment for PCa), despite disease progression on prior standard therapies. Using targeted next-generation sequencing on the primary and metastatic tumors, we found that all three patients had biallelic inactivation of BRCA2 , a tumor suppressor gene critical for homologous DNA repair. Notably, two had germline BRCA2 mutations, including a patient without compelling family history who was diagnosed at age 66 yr. The third patient had somatic BRCA2 homozygous copy loss. Biallelic BRCA2 inactivation in mCRPC warrants further exploration as a predictive biomarker for sensitivity to platinum chemotherapy.
While response rates to anti-PD1 therapy are low in unselected metastatic castration resistant prostate cancer (mCRPC) patients, those with inactivating mutations in mismatch repair (MMR) genes (i.e. ...MMR deficiency; MMRd) or microsatellite instability (MSI) are thought likely to respond favorably. To date, there is limited published data on this biologically distinct and clinically relevant subgroup's natural history and response to treatment.
We retrospectively identified patients at two academic institutions who had MMRd/MSI-high metastatic prostate cancer (PC). Clinical and pathologic characteristics at the time of diagnosis as well as response to standard therapies and immune checkpoint therapy were abstracted. Descriptive statistics, including PSA50 response (≥50% decline in PSA from baseline) and clinical/radiographic progression free survival (PFS), are reported.
27 men with MMRd and/or MSI-high metastatic PC were identified. 13 (48%) men had M1 disease at diagnosis and 19 of 24 (79%) men that underwent prostate biopsy had a Gleason score ≥8. Median overall survival from time of metastasis was not reached (95% CI: 33.6-NR mos) after a median follow up of 33.6 mos (95% CI: 23.8-50.5 mos). Seventeen men received pembrolizumab, of which 15 had PSA response data available. PSA50 responses to pembrolizumab occurred in 8 (53%) men. Median PFS was not reached (95% CI: 1.87-NR mos) and the estimated PFS at 6 months was 64.1% (95% CI: 33.7%-83.4%). Of those who achieved a PSA50 response, 7 (87.5%) remain on treatment without evidence of progression at a median follow up of 12 months (range 3-20 months).
MMRd PC is associated with high Gleason score and advanced disease at presentation. Response rates to standard therapies are comparable to those reported in unselected patients and response rate to checkpoint blockade is high. Our study is limited by small sample size, and more research is needed to identify additional factors that may predict response to immunotherapy.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Androgen receptor (AR) is reactivated in castration-resistant prostate cancer (CRPC) through mechanisms including marked increases in AR gene expression. We identify an enhancer in the AR second ...intron contributing to increased AR expression at low androgen levels in CRPC. Moreover, at increased androgen levels, the AR binds this site and represses AR gene expression through recruitment of lysine-specific demethylase 1 (LSD1) and H3K4me1,2 demethylation. AR similarly represses expression of multiple genes mediating androgen synthesis, DNA synthesis, and proliferation while stimulating genes mediating lipid and protein biosynthesis. Androgen levels in CRPC appear adequate to stimulate AR activity on enhancer elements, but not suppressor elements, resulting in increased expression of AR and AR repressed genes that contribute to cellular proliferation.
► AR gene expression in CRPC is increased by an enhancer in the second intron ► This enhancer is repressed by AR at high androgen levels through LSD1 recruitment ► AR represses genes mediating androgen synthesis, DNA synthesis, and cell cycling ► Decreased androgen in CRPC relieves repression but supports AR-dependent growth
Metastatic prostate cancer (mPC) comprises a spectrum of diverse phenotypes. However, the extent of inter- and intra-tumor heterogeneity is not established. Here we use digital spatial profiling ...(DSP) technology to quantitate transcript and protein abundance in spatially-distinct regions of mPCs. By assessing multiple discrete areas across multiple metastases, we find a high level of intra-patient homogeneity with respect to tumor phenotype. However, there are notable exceptions including tumors comprised of regions with high and low androgen receptor (AR) and neuroendocrine activity. While the vast majority of metastases examined are devoid of significant inflammatory infiltrates and lack PD1, PD-L1 and CTLA4, the B7-H3/CD276 immune checkpoint protein is highly expressed, particularly in mPCs with high AR activity. Our results demonstrate the utility of DSP for accurately classifying tumor phenotype, assessing tumor heterogeneity, and identifying aspects of tumor biology involving the immunological composition of metastases.
Acquired resistance to anticancer treatments is a substantial barrier to reducing the morbidity and mortality that is attributable to malignant tumors. Components of tissue microenvironments are ...recognized to profoundly influence cellular phenotypes, including susceptibilities to toxic insults. Using a genome-wide analysis of transcriptional responses to genotoxic stress induced by cancer therapeutics, we identified a spectrum of secreted proteins derived from the tumor microenvironment that includes the Wnt family member wingless-type MMTV integration site family member 16B (WNT16B). We determined that WNT16B expression is regulated by nuclear factor of κ light polypeptide gene enhancer in B cells 1 (NF-κB) after DNA damage and subsequently signals in a paracrine manner to activate the canonical Wnt program in tumor cells. The expression of WNT16B in the prostate tumor microenvironment attenuated the effects of cytotoxic chemotherapy in vivo, promoting tumor cell survival and disease progression. These results delineate a mechanism by which genotoxic therapies given in a cyclical manner can enhance subsequent treatment resistance through cell nonautonomous effects that are contributed by the tumor microenvironment.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Using integrative genomic analysis of 360 metastatic castration-resistant prostate cancer (mCRPC) samples, we identified a novel subtype of prostate cancer typified by biallelic loss of CDK12 that is ...mutually exclusive with tumors driven by DNA repair deficiency, ETS fusions, and SPOP mutations. CDK12 loss is enriched in mCRPC relative to clinically localized disease and characterized by focal tandem duplications (FTDs) that lead to increased gene fusions and marked differential gene expression. FTDs associated with CDK12 loss result in highly recurrent gains at loci of genes involved in the cell cycle and DNA replication. CDK12 mutant cases are baseline diploid and do not exhibit DNA mutational signatures linked to defects in homologous recombination. CDK12 mutant cases are associated with elevated neoantigen burden ensuing from fusion-induced chimeric open reading frames and increased tumor T cell infiltration/clonal expansion. CDK12 inactivation thereby defines a distinct class of mCRPC that may benefit from immune checkpoint immunotherapy.
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•CDK12 biallelic inactivating mutations define a distinct subtype of prostate cancer•CDK12 loss is associated with genomic instability and focal tandem duplications•CDK12 loss leads to increased gene fusions, neoantigen burden, and T cell infiltration•Patients with CDK12 mutant tumors may benefit from immune checkpoint inhibition
Loss of both alleles of the CDK12 gene defines a molecular subtype of metastatic castration-resistant prostate cancer that is potentially targetable with immune checkpoint inhibitors.
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