Nature of β-1,3-Glucan-Exposing Features on Candida albicans Cell Wall and Their Modulation

Candida albicans exists as a commensal of mucosal surfaces and the gastrointestinal tract without causing pathology. However, this fungus is also a common cause of mucosal and systemic infections when antifungal immune defenses become compromised. The activation of antifungal host defenses depends on the recognition of fungal pathogen-associated molecular patterns (PAMPs), such as β-1,3-glucan. In C. albicans, most β-1,3-glucan is present in the inner cell wall, concealed by the outer mannan layer, but some β-1,3-glucan becomes exposed at the cell surface. In response to host signals, such as lactate, C. albicans induces the Xog1 exoglucanase, which shaves exposed β-1,3-glucan from the cell surface, thereby reducing phagocytic recognition. We show here that β-1,3-glucan is exposed at bud scars and punctate foci on the lateral wall of yeast cells, that this exposed β-1,3-glucan is targeted during phagocytic attack, and that lactate-induced masking reduces β-1,3-glucan exposure at bud scars and at punctate foci. β-1,3-Glucan masking depends upon protein kinase A (PKA) signaling. We reveal that inactivating PKA, or its conserved downstream effectors, Sin3 and Mig1/Mig2, affects the amounts of the Xog1 and Eng1 glucanases in the C. albicans secretome and modulates β-1,3-glucan exposure. Furthermore, perturbing PKA, Sin3, or Mig1/Mig2 attenuates the virulence of lactate-exposed C. albicans cells in Galleria. Taken together, the data are consistent with the idea that β-1,3-glucan masking contributes to Candida pathogenicity. IMPORTANCE Microbes that coexist with humans have evolved ways of avoiding or evading our immunological defenses. These include the masking by these microbes of their "pathogen-associated molecular patterns" (PAMPs), which are recognized as "foreign" and used to activate protective immunity. The commensal fungus Candida albicans masks the proinflammatory PAMP β-1,3-glucan, which is an essential component of its cell wall. Most of this β-1,3-glucan is hidden beneath an outer layer of the cell wall on these microbes, but some can become exposed at the fungal cell surface. Using high-resolution confocal microscopy, we examine the nature of the exposed β-1,3-glucan at C. albicans bud scars and at punctate foci on the lateral cell wall, and we show that these features are targeted by innate immune cells. We also reveal that downstream effectors of protein kinase A (Mig1/Mig2, Sin3) regulate the secretion of major glucanases, modulate the levels of β-1,3-glucan exposure, and influence the virulence of C. albicans in an invertebrate model of systemic infection. Our data support the view that β-1,3-glucan masking contributes to immune evasion and the virulence of a major fungal pathogen of humans.

The future of fungi: threats and opportunities

The fungal kingdom represents an extraordinary diversity of organisms with profound impacts across animal, plant, and ecosystem health. Fungi simultaneously support life, by forming beneficial symbioses with plants and producing life-saving medicines, and bring death, by causing devastating diseases in humans, plants, and animals. With climate change, increased antimicrobial resistance, global trade, environmental degradation, and novel viruses altering the impact of fungi on health and disease, developing new approaches is now more crucial than ever to combat the threats posed by fungi and to harness their extraordinary potential for applications in human health, food supply, and environmental remediation. To address this aim, the Canadian Institute for Advanced Research (CIFAR) and the Burroughs Wellcome Fund convened a workshop to unite leading experts on fungal biology from academia and industry to strategize innovative solutions to global challenges and fungal threats. This report provides recommendations to accelerate fungal research and highlights the major research advances and ideas discussed at the meeting pertaining to 5 major topics: (1) Connections between fungi and climate change and ways to avert climate catastrophe; (2) Fungal threats to humans and ways to mitigate them; (3) Fungal threats to agriculture and food security and approaches to ensure a robust global food supply; (4) Fungal threats to animals and approaches to avoid species collapse and extinction; and (5) Opportunities presented by the fungal kingdom, including novel medicines and enzymes.

Physician Payments from Pharmaceutical Companies Related to Cancer Drugs

BACKGROUND

Drug manufacturers claim that the purpose of financial payments to physicians is to facilitate education about new drugs. This claim suggests 2 testable hypotheses: payments should not be associated with drug revenue and payments for each drug should decline over time as physicians become educated.

MATERIALS AND METHODS

We used open payments data on industry payments. We included payments for cancer drugs without generic/biosimilar competitors and used federal data sources to measure Medicare spending (a proxy for overall drug revenue) and a number of prescribers. We used generalized estimating equations (GEE) to model the drug-level association between industry payments and Medicare spending. Separately, we used GEE to estimate the change in payments with respect to the duration of time since initial FDA approval.

RESULTS

The sample included 89 drugs and 361 drug-year observations. The total value of industry payments for oncology drugs increased, from $53 333 854 in 2014 to $90 343 731 in 2018. There was no association between log-transformed mean, per-physician industry payments, and per-physician Medicare spending (estimate -0.001, 95%CI, -0.005 to 0.004). Payments for individual drugs decreased over time; estimated payments in the subsequent year for a drug with mean, per-physician payments of $1000 in the index year was: $681* for drugs 0-4 years since approval, $825 for 5-9 years, and $679* for ≥10 years (*P < .05).

CONCLUSIONS

Although industry-sponsored education may also serve marketing purposes, the absence of association between industry payments and Medicare spending and the decline in payments subsequent to approval are consistent with claims that industry payments function to facilitate physician education.

Use of the Iron-Responsive RBT5 Promoter for Regulated Expression in Candida albicans

Engineered conditional gene expression is used in appraisal of gene function and pathway relationships. For pathogens like the fungus Candida albicans, conditional expression systems are most useful if they are active in the infection environment and if they can be utilized in multiple clinical isolates. Here, we describe such a system. It employs the RBT5 promoter and can be implemented with a few PCRs. We validated the system with RBT5 promoter fusions to two genes that promote filamentation and polarized growth, UME6 and HGC1, and with efg1Δ/Δ mutants, which are defective in an activator of filamentous growth. An RBT5 promoter fusion to either gene enabled filamentous growth of an efg1Δ/Δ mutant of strain SC5314 in iron-limited media, including RPMI with serum and yeast extract-peptone-dextrose with bathophenanthrolinedisulfonic acid. The RBT5-UME6 fusion promoted filamentation of efg1Δ/Δ mutants in RPMI with serum of four other clinical C. albicans isolates as well. In a mouse model of disseminated candidiasis, the RBT5-UME6 fusion promoted filamentation of the SC5314 efg1Δ/Δ mutant in kidney tissue, an indication that the RBT5 promoter is active in the iron-limited host environment. The RBT5 promoter expands the conditional expression toolkit for C. albicans genetics. IMPORTANCE Genetic strategies have been vital for mechanistic analysis of biological processes. Here, we describe a genetic tool for the fungal pathogen Candida albicans.

Serum bridging molecules drive candidal invasion of human but not mouse endothelial cells

During hematogenously disseminated candidiasis, blood borne fungi must invade the endothelial cells that line the blood vessels to infect the deep tissues. Although Candida albicans, which forms hyphae, readily invades endothelial cells, other medically important species of Candida are poorly invasive in standard in vitro assays and have low virulence in immunocompetent mouse models of disseminated infection. Here, we show that Candida glabrata, Candida tropicalis, Candida parapsilosis, and Candida krusei can bind to vitronectin and high molecular weight kininogen present in human serum. Acting as bridging molecules, vitronectin and kininogen bind to αv integrins and the globular C1q receptor (gC1qR), inducing human endothelial cells to endocytose the fungus. This mechanism of endothelial cell invasion is poorly supported by mouse endothelial cells but can be restored when mouse endothelial cells are engineered to express human gC1qR or αv integrin. Overall, these data indicate that bridging molecule-mediated endocytosis is a common pathogenic strategy used by many medically important Candida spp. to invade human vascular endothelial cells.

The Prescription Drug User Fee Act: Much More Than User Fees

BACKGROUND

The Prescription Drug User Fee Act (PDUFA) is due for reauthorization in 2022. Beyond creating the user fee program which now generates a majority of the Food and Drug Administration (FDA) Human Drugs Program budget, PDUFA has made numerous additional changes to FDA policy during its 29-year history. FDA's budgetary dependence on user fees may advantage the industry in negotiating favorable policy changes through PDUFA.

METHODS

The full texts of all prior PDUFA reauthorization bills and all submitted public comments and meeting minutes for the 2022 reauthorization were reviewed. Provisions affecting FDA regulatory authority and processes were identified.

FINDINGS

PDUFA legislation has instituted a broad range of changes to FDA policy, including evidentiary standards for drug approval, accelerated pathways for approval, industry involvement in FDA decision-making, rules regarding industry information dissemination to providers, and market entry of generic drugs. Negotiations over the 2022 reauthorization suggest that industry priorities include increased application of real-world evidence, regulatory certainty, and increased communication between FDA and industry during the drug application process.

CONCLUSIONS

The need for PDUFA reauthorization every 5 years has created a recurring legislative vehicle through which far-ranging changes to FDA have been enacted, reshaping the agency's interactions and relationship with the regulated industry. The majority of policy changes enacted through PDUFA legislation have favored industry through decreasing regulatory standards, shortening approval times, and increasing industry involvement in FDA decision-making. FDA's budgetary dependence on the industry, the urgency of each PDUFA reauthorization's passage to maintain uninterrupted funding, and the industry's required participation in PDUFA negotiations may advantage the industry.

Increasing Financial Payments From Industry to Medical Oncologists in the United States, 2014-2017

BACKGROUND

Personal payments from the pharmaceutical industry to US physicians are common and are associated with changes in physicians' clinical practice and interpretation of clinical trial results. We assessed temporal trends in industry payments to oncologists, with particular emphasis on payments to authors of oncology clinical practice guideline and on payments related to immunotherapy drugs.

METHODS

We included US physicians with active National Plan and Provider Enumeration System records and demographic data available in the Centers for Medicare & Medicaid Services Physician Compare system who had a specialty type of medical oncology or general internal medicine. Medical oncologists serving on NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) Panels were identified manually. Industry payments, and the subset associated with PD-1/PD-L1 drugs, were identified in Open Payments, the federal repository of all transactions of financial value from industry to physicians and teaching hospitals, from 2014 to 2017.

RESULTS

There were 13,087 medical oncologists and 85,640 internists who received payments. The mean, annual, per-physician value of payments to oncologists increased from $3,811 in 2014 to $5,854 in 2017, and from $444 to $450 for internists; the median payment increased from $152 to $199 for oncologists and remained at $0 for internists. Oncologists who served on NCCN Guidelines Panels received a greater value in payments and experienced a greater relative increase: mean payments increased from $10,820 in 2014 to $18,977 in 2017, and median payments increased from $500 to $1,366. Among companies marketing PD-1/PD-L1 drugs, mean annual per-oncologist payments associated with PD-1/PD-L1 drugs increased from $28 to $773. Total per-oncologist payments from companies marketing PD-1/PD-L1 drugs experienced a 165% increase from 2014 to 2017, compared with a 31% increase among similar companies not marketing PD-1/PD-L1 drugs.

CONCLUSIONS

Pharmaceutical industry payments increased for US oncologists from 2014 to 2017 more than for general internists. The increase was greater among oncologists contributing to clinical practice guidelines and among pharmaceutical companies marketing PD-1/PD-L1 drugs. The increasing flow of money from industry to US oncologists supports ongoing concern regarding commercial interests in guideline development and clinical decision-making.

Real-World Use of Bone Modifying Agents in Metastatic Castration-Sensitive Prostate Cancer

BACKGROUND

Bone modifying agent (BMA) therapy is recommended for metastatic castration-resistant prostate cancer (mCRPC) but not metastatic castration-sensitive prostate cancer (mCSPC). BMA treatment in mCSPC may therefore constitute overuse.

METHODS

In this retrospective cohort study using linked Surveillance, Epidemiology, and End Results-Medicare data, we included patients diagnosed with stage IV prostate adenocarcinoma from 2007-2015, who were age ≥66 years at diagnosis and received androgen deprivation or antiandrogen therapy. We excluded patients who had previously received BMAs or had existing osteoporosis, osteopenia, hypercalcemia, or prior bone fracture. The primary outcome was receipt of BMA (zoledronic acid or denosumab) within 180 days of diagnosis (emergence of CRPC within this time frame is unlikely). Secondary outcome was BMA within 90 days. Exposures of interest included practice location (physician office vs. hospital outpatient) and specialty (medical oncologist vs. urologist) of treating physician.

RESULTS

Our sample included 2,627 patients, of which 52.9% were treated by medical oncologists and 47.1% by urologists; 77.7% and 22.3% received care in physician office and hospital outpatient locations, respectively. Overall, 23.6% received a BMA within 180 days; 18.4% did within 90 days. BMA therapy was more common among patients treated by oncologists (odds ratio = 8.23, 95% confidence interval = 6.41 to 10.57) and in physician office locations (odds ratio = 1.33, 95% confidence interval = 1.06 to 1.69). Utilization has increased: 17.3% of patients received BMAs from 2007-2009 (17.3% zoledronic acid, 0% denosumab), and 28.1% from 2012-2015 (8.4% zoledronic acid, 20.3% denosumab).

CONCLUSIONS

Among mCSPC patients who had no evidence of high osteoporotic fracture risk, over one-quarter received BMAs in recent years. This overuse may lead to excess costs and toxicity.

Personal Payments from Pharmaceutical Companies to Authors of Oncology Clinical Practice Guidelines

BACKGROUND

Oncologists who author clinical practice guidelines frequently have financial relationships with the pharmaceutical industry. It is unknown whether participation on clinical practice guideline committees is associated with differences in the amounts of industry money received.

MATERIALS AND METHODS

We conducted a nested case-control study from August 2013 to December 2018. We manually abstracted membership records of National Comprehensive Cancer Network (NCCN) Guidelines committees for the 20 most common cancers and linked to Open Payments. The study sample included medical oncologists selected to join an NCCN Guidelines committee ("joiners") during the study period. Joiners were matched 1:2 to medical oncologists who had no participation on NCCN committees (controls) by gender, NCCN institution, and medical school graduation year. We performed difference-in-differences (DiD) estimation to assess whether selection to an NCCN committee was associated with the dollar value of payments received from industry, using generalized estimating equations to address correlation between matched pairs and between repeated observations of the same pair.

RESULTS

During the study period, 54 physicians joined an NCCN Guidelines committee. These physicians received more payments than matched controls in the year prior to joining ($11,259 vs. $3,427; p = .02); this difference did not increase in the year after joining (DiD = $731; p = .45).

CONCLUSION

Medical oncologists selected to NCCN Guidelines committees had greater financial ties to industry than their peers. The potential influence of industry in oncology clinical practice guidelines may be reduced through the selection of committee members with fewer ties to industry.

IMPLICATIONS FOR PRACTICE

Oncologists who author clinical practice guidelines frequently have financial conflicts of interest with the pharmaceutical industry. This creates concern about the potential for industry influence on guidelines. However, it is unknown whether oncologists who author guidelines have greater industry relationships than their peers. This study compared medical oncologists who were newly selected to join a National Comprehensive Cancer Network (NCCN) Guidelines panel with medical oncologists at the same institutions and at similar career stages. At the time they joined, oncologists joining NCCN Guidelines panels had received more than three times the dollar value of industry payments than their peers. The potential for industry influence may be reduced by the selection of less-conflicted panel members.

Environmentally contingent control of Candida albicans cell wall integrity by transcriptional regulator Cup9

The fungal pathogen Candida albicans is surrounded by a cell wall that is the target of caspofungin and other echinocandin antifungals. Candida albicans can grow in several morphological forms, notably budding yeast and hyphae. Yeast and hyphal forms differ in cell wall composition, leading us to hypothesize that there may be distinct genes required for yeast and hyphal responses to caspofungin. Mutants in 27 genes reported previously to be caspofungin hypersensitive under yeast growth conditions were all caspofungin hypersensitive under hyphal growth conditions as well. However, a screen of mutants defective in transcription factor genes revealed that Cup9 is required for normal caspofungin tolerance under hyphal and not yeast growth conditions. In a hyphal-defective efg1Δ/Δ background, Cup9 is still required for normal caspofungin tolerance. This result argues that Cup9 function is related to growth conditions rather than cell morphology. RNA-seq conducted under hyphal growth conditions indicated that 361 genes were up-regulated and 145 genes were down-regulated in response to caspofungin treatment. Both classes of caspofungin-responsive genes were enriched for cell wall-related proteins, as expected for a response to disruption of cell wall integrity and biosynthesis. The cup9Δ/Δ mutant, treated with caspofungin, had reduced RNA levels of 40 caspofungin up-regulated genes, and had increased RNA levels of 8 caspofungin down-regulated genes, an indication that Cup9 has a narrow rather than global role in the cell wall integrity response. Five Cup9-activated surface-protein genes have roles in cell wall integrity, based on mutant analysis published previously (PGA31 and IFF11) or shown here (ORF19.3499, ORF19.851, or PGA28), and therefore may explain the hypersensitivity of the cup9Δ/Δmutant to caspofungin. Our findings define Cup9 as a new determinant of caspofungin susceptibility.

The Role of Physician Professional Networks in Physicians' Receipt of Pharmaceutical and Medical Device Industries' Payments

BACKGROUND

Financial relationships between physicians and the pharmaceutical and medical device industries are common, but the factors associated with physicians receiving payments are unknown.

OBJECTIVE

The objective of this study is to evaluate the influence of physicians' professional networks' characteristics on the receipt of payments among physicians.

DESIGN

Network analysis of cross-sectional data PARTICIPANTS: US physicians who shared Medicare patients with other physicians in 2015 (N=357,813).

EXPOSURE (INTERVENTION)

Proportion of a physician's professional network that received industry payments and other network characteristics including number of physician connections, how central the physician is within the network, and the tightness of the referral network in which a physician is located.

MAIN OUTCOME MEASURES

Relative risk of receiving industry payments. We used modified Poisson regression to control for confounding by gender, time since graduation, practice size, and practice setting (teaching hospital vs. not). We included dummy variables for specialty and hospital referral region level.

KEY RESULTS

The proportion of a physician's peers in their professional network that received payments was strongly associated with receipt of pharmaceutical or device industry payments by the physician (top vs bottom quartile aRR=1.28, 95%CI=1.25-1.31). Physician's centrality within a network had a small positive effect on receiving payment (top vs bottom quartile aRR=1.02, 95%CI=1.01-1.04). Network density also had a small negative association with receipt of payment (top vs bottom quartile aRR=0.97, 95%CI=0.96-0.98).

CONCLUSIONS

Network characteristics, particularly the receipt of payments among physicians one shares patients with, are associated with whether a physician receives payments. This finding has implications for institutional regulation of industry payments to physicians and demonstrates how institutional policy may impact not only the physicians within the institution but also physicians outside of the institution.

Intravital Imaging of Candida albicans Identifies Differential In Vitro and In Vivo Filamentation Phenotypes for Transcription Factor Deletion Mutants

Candida albicans is an important cause of human fungal infections. A widely studied virulence trait of C. albicans is its ability to undergo filamentation to hyphae and pseudohyphae. Although yeast, pseudohyphae, and hyphae are present in pathological samples of infected mammalian tissue, it has been challenging to characterize the role of regulatory networks and specific genes during in vivo filamentation. In addition, the phenotypic heterogeneity of C. albicans clinical isolates is becoming increasingly recognized, while correlating this heterogeneity with pathogenesis remains an important goal. Here, we describe the use of an intravital imaging approach to characterize C. albicans filamentation in a mammalian model of infection by taking advantage of the translucence of mouse pinna (ears). Using this model, we have found that the in vitro and in vivo filamentation phenotypes of different C. albicans isolates can vary significantly, particularly when in vivo filamentation is compared to solid agar-based assays. We also show that the well-characterized transcriptional regulators Efg1 and Brg1 appear to play important roles both in vivo and in vitro. In contrast, Ume6 is much more important in vitro than in vivo. Finally, strains that are dependent on Bcr1 for in vitro filamentation are able to form filaments in vivo in its absence. This intravital imaging approach provides a new approach to the systematic characterization of this important virulence trait during mammalian infection. Our initial studies provide support for the notion that the regulation and initiation of C. albicans filamentation in vivo is distinct from in vitro induction. IMPORTANCE Candida albicans is one of the most common causes of fungal infections in humans. C. albicans undergoes a transition from a round yeast form to a filamentous form during infection, which is critical for its ability to cause disease. Although this transition has been studied in the laboratory for years, methods to do so in an animal model of infection have been limited. We have developed a microscopy method to visualize fluorescently labeled C. albicans undergoing this transition in the subcutaneous tissue of mice. Our studies indicate that the regulation of C. albicans filamentation during infection is distinct from that observed in laboratory conditions.

Industry Payments to Rheumatologists Ought to be Going Down, Not Up

In the current issue of Arthritis & Rheumatology, Putman et al report findings regarding the distribution and temporal trends of industry payments to US rheumatologists [cite ar-21-0182]. Their findings are in line with similar reports from other medical and surgical specialties, and highlight the overarching concern regarding the ability of industry payments to adversely affect care quality within the specific context of rheumatology practice.

Determining Aspergillus fumigatus transcription factor expression and function during invasion of the mammalian lung

To gain a better understanding of the transcriptional response of Aspergillus fumigatus during invasive pulmonary infection, we used a NanoString nCounter to assess the transcript levels of 467 A. fumigatus genes during growth in the lungs of immunosuppressed mice. These genes included ones known to respond to diverse environmental conditions and those encoding most transcription factors in the A. fumigatus genome. We found that invasive growth in vivo induces a unique transcriptional profile as the organism responds to nutrient limitation and attack by host phagocytes. This in vivo transcriptional response is largely mimicked by in vitro growth in Aspergillus minimal medium that is deficient in nitrogen, iron, and/or zinc. From the transcriptional profiling data, we selected 9 transcription factor genes that were either highly expressed or strongly up-regulated during in vivo growth. Deletion mutants were constructed for each of these genes and assessed for virulence in mice. Two transcription factor genes were found to be required for maximal virulence. One was rlmA, which is required for the organism to achieve maximal fungal burden in the lung. The other was sltA, which regulates of the expression of multiple secondary metabolite gene clusters and mycotoxin genes independently of laeA. Using deletion and overexpression mutants, we determined that the attenuated virulence of the ΔsltA mutant is due in part to decreased expression aspf1, which specifies a ribotoxin, but is not mediated by reduced expression of the fumigaclavine gene cluster or the fumagillin-pseruotin supercluster. Thus, in vivo transcriptional profiling focused on transcription factors genes provides a facile approach to identifying novel virulence regulators.

Although A. fumigatus causes the majority of cases of invasive aspergillosis, the function of most genes in its genome remains unknown. To identify genes encoding transcription factors that may be important for virulence, we used a NanoString nCounter to measure the mRNA levels of A. fumigatus transcription factor genes in the lungs of mice with invasive aspergillosis. The transcriptional profiling data indicate that the organism is exposed to nutrient limitation and stress during growth in the lungs, and that it responds by up-regulating genes that encode mycotoxins and secondary metabolites. In vitro, this response was most closely mimicked by growth in medium that was deficient in nitrogen, iron and/or zinc. Using the transcriptional profiling data, we identified two transcription factors that govern A. fumigatus virulence. These were RlmA, which is governs factors that enables the organism to proliferate maximally in the lung and SltA, which controls the production of mycotoxins and secondary metabolites.

Are Financial Payments From the Pharmaceutical Industry Associated With Physician Prescribing? : A Systematic Review

BACKGROUND

Financial payments from the drug industry to U.S. physicians are common. Payments may influence physicians' clinical decision making and drug prescribing.

PURPOSE

To evaluate whether receipt of payments from the drug industry is associated with physician prescribing practices.

DATA SOURCES

MEDLINE (Ovid), Embase, the Cochrane Library, Web of Science, and EconLit were searched without language restrictions. The search had no limiting start date and concluded on 16 September 2020.

STUDY SELECTION

Studies that estimated the association between receipt of industry payments (exposure) and prescribing (outcome).

DATA EXTRACTION

Pairs of reviewers extracted the primary analysis or analyses from each study and evaluated risk of bias (ROB).

DATA SYNTHESIS

Thirty-six studies comprising 101 analyses were included. Most studies (n = 30) identified a positive association between payments and prescribing in all analyses; the remainder (n = 6) had a mix of positive and null findings. No study had only null findings. Of 101 individual analyses, 89 identified a positive association. Payments were associated with increased prescribing of the paying company's drug, increased prescribing costs, and increased prescribing of branded drugs. Nine studies assessed and found evidence of a temporal association; 25 assessed and found evidence of a dose-response relationship.

LIMITATION

The design was observational, 21 of 36 studies had serious ROB, and publication bias was possible.

CONCLUSION

The association between industry payments and physician prescribing was consistent across all studies that have evaluated this association. Findings regarding a temporal association and dose-response suggest a causal relationship.

PRIMARY FUNDING SOURCE

National Cancer Institute.

Association between Site-of-Care and the Cost and Modality of Radiotherapy for Prostate Cancer: Analysis of Medicare Beneficiaries from 2015 to 2017

Among 84,447 radiotherapy (RT) courses for Medicare beneficiaries age ≥ 65 with prostate cancer treated with external beam RT (EBRT), brachytherapy, or both, 42,608 (51%) were delivered in hospital-affiliated and 41,695 (49%) in freestanding facilities. Freestanding centers were less likely to use EBRT + brachytherapy than EBRT (OR 0.84 [95%CI 0.84-0.84]; p < .001). Treatment was more costly in freestanding centers (mean difference $2,597 [95%CI $2,475-2,719]; p < .001). Adjusting for modality and fractionation, RT in hospital-affiliated centers was more costly (mean difference $773 [95%CI $693-853]; p < .001). Freestanding centers utilized more expensive RT delivery, but factors unrelated to RT modality or fractionation rendered RT more costly at hospital-affiliated centers.

Activation of EphA2-EGFR signaling in oral epithelial cells by Candida albicans virulence factors

During oropharyngeal candidiasis (OPC), Candida albicans invades and damages oral epithelial cells, which respond by producing proinflammatory mediators that recruit phagocytes to foci of infection. The ephrin type-A receptor 2 (EphA2) detects β-glucan and plays a central role in stimulating epithelial cells to release proinflammatory mediators during OPC. The epidermal growth factor receptor (EGFR) also interacts with C. albicans and is known to be activated by the Als3 adhesin/invasin and the candidalysin pore-forming toxin. Here, we investigated the interactions among EphA2, EGFR, Als3 and candidalysin during OPC. We found that EGFR and EphA2 constitutively associate with each other as part of a heteromeric physical complex and are mutually dependent for C. albicans-induced activation. Als3-mediated endocytosis of a C. albicans hypha leads to the formation of an endocytic vacuole where candidalysin accumulates at high concentration. Thus, Als3 potentiates targeting of candidalysin, and both Als3 and candidalysin are required for C. albicans to cause maximal damage to oral epithelial cells, sustain activation of EphA2 and EGFR, and stimulate pro-inflammatory cytokine and chemokine secretion. In the mouse model of OPC, C. albicans-induced production of CXCL1/KC and CCL20 is dependent on the presence of candidalysin and EGFR, but independent of Als3. The production of IL-1α and IL-17A also requires candidalysin but is independent of Als3 and EGFR. The production of TNFα requires Als1, Als3, and candidalysin. Collectively, these results delineate the complex interplay among host cell receptors EphA2 and EGFR and C. albicans virulence factors Als1, Als3 and candidalysin during the induction of OPC and the resulting oral inflammatory response.

Oropharyngeal candidiasis occurs when the fungus Candida albicans proliferates in the mouth to a point at which tissue damage occurs. The disease is characterized by fungal invasion of the superficial epithelium and a localized inflammatory response. Two C. albicans virulence factors contribute to the pathogenesis of OPC, Als3 which enables the organism to adhere to and invade host cells, and candidalysin which is a pore-forming toxin that damages host cells. Two epithelial cell receptors, ephrin type-A receptor 2 (EphA2) and the epidermal growth factor receptor (EGFR) are activated by C. albicans. Here, we show that EphA2 and EGFR form part of complex wherein these co-receptors are required to activate each other. Als3 enhances the host cell targeting of candidalysin by stimulating epithelial cell endocytosis of C. albicans, leading to the formation of an endocytic vacuole in which candidalysin accumulates. Thus, Als3 and candidalysin synergize to damage epithelial cells, activate EphA2 and EGFR, and stimulate the production of inflammatory mediators. In the mouse model of OPC, candidalysin elicits of a subset of the oral inflammatory response molecular repertoire. Of the cytokines and chemokines induced by this toxin, some require the activation of EGFR while others are induced independently of EGFR. Collectively, this work provides a deeper understanding of the interactions among C. albicans virulence factors, host cell receptors and immune responses during OPC.

Targeted Genetic Changes in Candida albicans Using Transient CRISPR-Cas9 Expression

Candida albicans is an opportunistic fungal pathogen responsible for significant disease and mortality. Absent complete mating and other convenient methods, dissection of its virulence factors relies on robust tools to delete, complement, and otherwise modify genes of interest in this diploid organism. Here we describe the design principles and use of CRISPR associated nuclease 9 (Cas9) and single-guide RNAs transiently expressed from PCR cassettes to modify genes of interest, generating homozygous mutants in a single transformation step. © 2021 Wiley Periodicals LLC. Basic Protocol 1: PCR amplification of CRISPR components Basic Protocol 2: Transformation of Candida albicans Basic Protocol 3: Selecting and genotyping transformants Alternate Protocol 1: Deletion with recyclable markers by CRISPR induced marker excision (CRIME) Alternate Protocol 2: Knock-in and combining multiple cassettes with overlapping homology.

Candida albicans Culture, Cell Harvesting, and Total RNA Extraction

Transcriptional analysis has become a cornerstone of biological research, and with the advent of cheaper and more efficient sequencing technology over the last decade, there exists a need for high-yield and efficient RNA extraction techniques. Fungi such as the human pathogen Candida albicans present a unique obstacle to RNA purification in the form of the tough cell wall made up of many different components such as chitin that are resistant to many common mammalian or bacterial cell lysis methods. Typical in vitro C. albicans cell harvesting methods can be time consuming and expensive if many samples are being processed with multiple opportunities for product loss or sample variation. Harvesting cells via vacuum filtration rather than centrifugation cuts down on time before the cells are frozen and therefore the available time for the RNA expression profile to change. Vacuum filtration is preferred for C. albicans for two main reasons: cell lysis is faster on non-pelleted cells due to increased exposed surface area, and filamentous cells are difficult to pellet in the first place unlike yeast or bacterial cells. Using mechanical cell lysis, by way of zirconia/silica beads, cuts down on time for processing as well as overall cost compared to enzymatic treatments. Overall, this method is a fast, efficient, and high-yield way to extract total RNA from in vitro cultures of C. albicans.

Association Between Clinical Value and Financial Cost of Cancer Treatments: A Cross-Sectional Analysis

BACKGROUND

The cost of cancer treatment has increased significantly in recent decades, but it is unclear whether these costs have been associated with commensurate improvement in clinical value. This study aimed to assess the association between the cost of cancer treatment and 4 of the 5 NCCN Evidence Blocks (EB) measures of clinical value: efficacy of regimen/agent, safety of regimen/agent, quality of evidence, and consistency of evidence.

METHODS

This is a cross-sectional, observational study. We obtained NCCN EB ratings for all recommended, first-line, and/or maintenance treatments for the 30 most prevalent cancers in the United States and calculated direct pharmacologic treatment costs (drug acquisition, administration fees, guideline-concordant supportive care medications) using Medicare reimbursement rates in January 2019. We used generalized estimating equations to estimate the association between NCCN EB measures and treatment cost with clustering at the level of the treatment indication.

RESULTS

A total of 1,386 treatments were included. Among time-unlimited treatments (those administered on an ongoing basis without a predetermined stopping point), monthly cost was positively associated with efficacy ($3,036; 95% CI, $1,782 to $4,289) and quality of evidence ($1,509; 95% CI, $171 to $2,847) but negatively associated with safety (-$1,470; 95% CI, -$2,790 to -$151) and consistency of evidence (-$2,003; 95% CI, -$3,420 to -$586). Among time-limited treatments (those administered for a predetermined interval or number of cycles), no NCCN EB measure was significantly associated with treatment cost.

CONCLUSIONS

An association between NCCN EB measures and treatment cost was inconsistent, and the magnitude of the association was small compared with the degree of cost variation among treatments with the same EB scores. The clinical value of cancer treatments does not seem to be a primary determinant of treatment cost.

Predicting bovine tuberculosis status of dairy cows from mid-infrared spectral data of milk using deep learning

Bovine tuberculosis (bTB) is a zoonotic disease in cattle that is transmissible to humans, distributed worldwide, and considered endemic throughout much of England and Wales. Mid-infrared (MIR) analysis of milk is used routinely to predict fat and protein concentration, and is also a robust predictor of several other economically important traits including individual fatty acids and body energy. This study predicted bTB status of UK dairy cows using their MIR spectral profiles collected as part of routine milk recording. Bovine tuberculosis data were collected as part of the national bTB testing program for Scotland, England, and Wales; these data provided information from over 40,500 bTB herd breakdowns. Corresponding individual cow life-history data were also available and provided information on births, movements, and deaths of all cows in the study. Data relating to single intradermal comparative cervical tuberculin (SICCT) skin-test results, culture, slaughter status, and presence of lesions were combined to create a binary bTB phenotype labeled 0 to represent nonresponders (i.e., healthy cows) and 1 to represent responders (i.e., bTB-affected cows). Contemporaneous individual milk MIR spectral data were collected as part of monthly routine milk recording and matched to bTB status of individual animals on the single intradermal comparative cervical tuberculin test date (±15 d). Deep learning, a sub-branch of machine learning, was used to train artificial neural networks and develop a prediction pipeline for subsequent use in national herds as part of routine milk recording. Spectra were first converted to 53 × 20-pixel PNG images, then used to train a deep convolutional neural network. Deep convolutional neural networks resulted in a bTB prediction accuracy (i.e., the number of correct predictions divided by the total number of predictions) of 71% after training for 278 epochs. This was accompanied by both a low validation loss (0.71) and moderate sensitivity and specificity (0.79 and 0.65, respectively). To balance data in each class, additional training data were synthesized using the synthetic minority over sampling technique. Accuracy was further increased to 95% (after 295 epochs), with corresponding validation loss minimized (0.26), when synthesized data were included during training of the network. Sensitivity and specificity also saw a 1.22- and 1.45-fold increase to 0.96 and 0.94, respectively, when synthesized data were included during training. We believe this study to be the first of its kind to predict bTB status from milk MIR spectral data. We also believe it to be the first study to use milk MIR spectral data to predict a disease phenotype, and posit that the automated prediction of bTB status at routine milk recording could provide farmers with a robust tool that enables them to make early management decisions on potential reactor cows, and thus help slow the spread of bTB.

Trends in Female Representation on NCCN Guideline Panels

BACKGROUND

NCCN produces highly influential disease-specific oncology clinical practice guidelines. Because the number of women in academic oncology has increased, we assessed whether the composition of NCCN Guidelines Panels reflected this trend.

METHODS

Using historical guidelines requested from NCCN, we investigated time trends for female representation on 21 NCCN Guidelines Panels and analyzed the trends for female-predominant cancers (breast, ovarian, uterine, and cervical) compared with all cancers.

RESULTS

From 2013 to 2019, there was an increase from 123 women of 541 total panelists (22.7%) to 175 women of 542 panelists (32.3%). Within the 4 female-predominant cancers, the increase was more rapid: from 30 of 101 total panelists (29.7%) to 66 of 118 panelists (56.4%). Excluding female-predominant cancers, increases were minimal.

CONCLUSIONS

There could be multiple explanations for these differing trends, including the possibility of more rapid increases in the underlying pool of female physician-scientists in female-predominant specialties or more efforts to increase the representation of women in decisions about the standard of care in cancers predominantly affecting women.