Human papillomavirus (HPV) infection, particularly with HPV types 16 and 18, is the most prevalent viral carcinogen among head and neck cancers. Notably, HPV-positive (HPV+) status is associated with improved survival and treatment response compared to HPV-negative (HPV−) cancers. However, comprehensive and rigorous analyses of HPV serology remain limited by substantial heterogeneity and numerous outliers. In this study, we analyzed 454 serum samples from 151 patients with squamous cell carcinoma of the head and neck, collected at a single institution between 2007 and 2020. Total IgG antibody titers against the E7 oncoproteins of HPV16 and HPV18 were measured using ELISA (Khanal et al., 2015). The 95
Immunosuppression commonly disrupts the homeostasis of mutated normal skin, leading to widespread skin dysplasia and field cancerization. However, the immune system’s role in maintaining the normal state of mutated tissues remains uncertain. Herein, we demonstrate that T cell immunity to cutaneotropic papillomaviruses promotes the homeostasis of ultraviolet radiation-damaged skin. Mouse papillomavirus (MmuPV1) colonization blocks the expansion of mutant p53 clones in the epidermis in a CD8+ T cell-dependent manner. MmuPV1 activity is increased in p53-deficient keratinocytes, leading to their specific targeting by CD8+ T cells in the skin. Sun-exposed human skin containing mutant p53 clones shows increased epidermal beta-human papillomavirus (β-HPV) activity and CD8+ T cell infiltrates compared with sun-protected skin. The expansion of mutant p53 clones in premalignant skin lesions associates with β-HPV loss. Thus, immunity to commensal HPVs contributes to the homeostasis of mutated normal skin, highlighting the role of virome-immune system interactions in preserving aging human tissues.
Cutaneous squamous cell carcinoma (cSCC) is the second most common cancer, with increased incidence in immunosuppressed patients. β-Human papillomavirus has been proposed as a contributor to cSCC risk partly on the basis of increased β-human papillomavirus viral load and seropositivity observed among patients with cSCC. Experimental data in mice colonized with mouse papillomavirus type 1 suggest that T cell immunity against β-human papillomavirus suppresses skin cancer in immunocompetent hosts, and the loss of this immunity leads to the increased risk of cSCC. In this study, we show that CD8+ T cell depletion in mouse papillomavirus type 1‒colonized mice that underwent skin carcinogenesis protocol led to increased viral load in the skin and seropositivity for anti‒mouse papillomavirus type 1 antibodies. These findings provide evidence that compromised T cell immunity can be the link that connects increased β-human papillomavirus detection to cSCC risk.
The detection of early-stage cancer offers patients the best chance of treatment and could help reduce cancer mortality rates. However, cancer cells or biomarkers are present in extremely small amounts in the early stages of cancer, requiring high-precision quantitative approaches with high sensitivity for accurate detection. With the advantages of simplicity, rapid response, reusability, and a low cost, aptamer-based electrochemical biosensors have received considerable attention as a promising approach for the clinical diagnosis of early-stage cancer. Various methods for developing highly sensitive aptasensors for the early detection of cancers in clinical samples are in progress. In this article, we discuss recent advances in the development of electrochemical aptasensors for the early detection of different cancer biomarkers and cells based on different detection strategies. Clinical applications of the aptasensors and future perspectives are also discussed.
High-risk human papillomavirus (HPV) is among the most common causes of head and neck cancer (HNC) with increasing incidence. HPV-associated HNC patients’ clinical response to treatment varies drastically, which has made treatment de-escalation clinical trials challenging. To address the need for noninvasive biomarkers that differentiate patient outcomes, serum antibodies to E7 oncoprotein levels were evaluated in serial serum specimens from HPV-positive HNC patients ( n = 48 ). We have found that increasing antibodies to E7 throughout treatment correlates with increased cancer recurrence or progression to mortality ( p = .004 ) with 100% specificity as a predictive test.
With the increasing rise of antibiotic-resistant pathogens, a simple and rapid detection of antibiotic resistance gene (ARG) is crucial to mitigate the spreading of antibiotic resistance. DNA-binding zinc finger proteins (ZFPs) can be engineered to recognize specific double-stranded (ds) DNA sequences in ARG. Here, we designed a simple and rapid method to detect ARG in bacteria utilizing engineered ZFPs and 2D nanosheet graphene oxide (GO) as a sensing platform. Our approach relies on the on and off effect of fluorescence signal in the presence and absence of target ARG, respectively. By taking advantage of the unique quenching capability of GO due to its electronic property, quantum dot (QD)-labeled ZFPs are adsorbed onto the GO sheets, and their fluorescence signal is quenched by proximal GO sheets through fluorescence resonance energy transfer (FRET). In the presence of target DNA, ZFP binding to the target DNA induces dissociation from GO, thereby restoring the fluorescence signal. Our system detects target DNA through restoration of QD emission as the restored signal increases directly with target DNA concentrations. Engineered ZFPs were able to detect specific dsDNA of the tetracycline resistance gene tetM with high specificity after only 10 min incubation on our GO-based sensing system. Our sensing system employed one-step FRET-based ZFP and GO combined technology to enable rapid and quantitative detection of ARG, providing a limit of detection as low as 1 nM. This study demonstrated the application of GO in conjunction with engineered DNA-binding domains for the direct detection of dsDNA with great potential as a rapid and reliable screening and detecton method against the growing threat of antibiotic resistant bacteria.
Background: Human papillomavirus (HPV) etiology has become evident in head and neck cancers (HNCs) and HPV positivity showed a strong association with its malignant progression. Since aberrant DNA methylation is known to drive carcinogenesis and progression in HNCs, we investigated to determine target gene(s) associated with this modification. Methods: We characterized epigenetic changes in tumor-related genes (TRGs) that are known to be associated with HNC development and its progression. Results: The expression levels of 42 candidate HNC-associated genes were analyzed. Of these, 7 TGRs (CHFR, RAR beta, GRB7, EREG, RUNX2, RUNX3, and SMG-1) showed decreased expressions in HPV-positive ((+)) HNC cells compared with HPV-negative ((-)) HNC cells. When gene expression levels were compared corresponding to the DNA methylation conditions, GRB7 and EREG showed significant differential expression between HPV+ and HPV- cells, which suggested these genes as primary targets of epigenetic regulation in HPV-induced carcinogenesis. Furthermore, treatment with a demethylation agent, 5-aza-2'-deoxycytidine (5-aza-dc), caused restoration of EREG expression and was associated with hypomethylation of its promoter in HPV+ cells, while no changes was noted in HPV- cells. EREG promoter hypermethylation in HPV+ cells was confirmed using methylation-specific PCR (MS-PCR). Conclusion: We conclude that EREG is the target of epigenetic regulation in HPV+ HNCs and its suppressed expression through promoter hypermethylation is associated with the development of HPV-associated HNCs.
Immunosuppression increases the risk of cancers that are associated with viral infection1. In particular, the risk of squamous cell carcinoma of the skin—which has been associated with beta human papillomavirus (β-HPV) infection—is increased by more than 100-fold in immunosuppressed patients2–4. Previous studies have not established a causative role for HPVs in driving the development of skin cancer. Here we show that T cell immunity against commensal papillomaviruses suppresses skin cancer in immunocompetent hosts, and the loss of this immunity—rather than the oncogenic effect of HPVs—causes the markedly increased risk of skin cancer in immunosuppressed patients. To investigate the effects of papillomavirus on carcinogen-driven skin cancer, we colonized several strains of immunocompetent mice with mouse papillomavirus type 1 (MmuPV1)5. Mice with natural immunity against MmuPV1 after colonization and acquired immunity through the transfer of T cells from immune mice or by MmuPV1 vaccination were protected against skin carcinogenesis induced by chemicals or by ultraviolet radiation in a manner dependent on CD8+ T cells. RNA and DNA in situ hybridization probes for 25 commensal β-HPVs revealed a significant reduction in viral activity and load in human skin cancer compared with the adjacent healthy skin, suggesting a strong immune selection against virus-positive malignant cells. Consistently, E7 peptides from β-HPVs activated CD8+ T cells from unaffected human skin. Our findings reveal a beneficial role for commensal viruses and establish a foundation for immune-based approaches that could block the development of skin cancer by boosting immunity against the commensal HPVs present in all of our skin. A mouse model of papillomavirus infection reveals that skin colonization with commensal papillomaviruses protects the immunocompetent host against chemical- and UV-induced skin cancer through CD8+ T cell immunity.
Recombinase polymerase amplification (RPA) has been combined with electrochemical detection for simple and rapid point-of-care testing. However, there are two major hindrances to this simple and rapid testing: (i) washing or purification steps are required to remove unbound labeled probes and interfering species in the sample; (ii) it is difficult to quantify double-stranded DNA (dsDNA) electrochemically by using biospecific affinity binding without dsDNA denaturation. In the present study, we describe a wash-free and rapid electrochemical method to detect RPA-amplified dsDNAs using a zinc finger protein, Zif268. Electrochemical detection is achieved using proximity-dependent electron mediation of ferrocenemethanol between a glucose-oxidase (GOx) label and an electrode, which differentiates the specifically electrode-bound and -unbound labels without a washing or purification step. RPA-amplified dsDNA containing a biotin-terminated forward primer is specifically bound to a neutravidin-modified electrode, and GOx-conjugated Zif268 is specifically bound to the dsDNA. The whole detection is performed within 17 min (15 min for the RPA reaction and <2 min for the electrochemical measurement). Electrochemical detection is carried out without an additional incubation period, because the specific binding between Zif268 and the dsDNA occurs during the RPA reaction. The detection method could discriminate between target template DNA of Piscirickettsia salmonis and nontarget DNAs (random sequence and calf thymus DNA). The detection limit for the target DNA is approximately 300 copies in 13.2 μL, indicating that the detection method is ultrasensitive. We believe that the method could offer a promising solution for simple and rapid point-of-care testing.
A specific double-stranded DNA sensing system is of great interest for diagnostic and other biomedical applications. Zinc finger domains, which recognize double-stranded DNA, can be engineered to form custom DNA-binding proteins for the recognition of specific DNA sequences. As a proof of concept, a sequence-enabled reassembly of a TEM-1 β-lactamase system (SEER-LAC) was previously demonstrated to develop zinc finger protein (ZFP) arrays for the detection of a double-stranded bacterial DNA sequence. Here, we implemented the SEER-LAC system to demonstrate the direct detection of pathogen-specific DNA sequences present in E. coli O157:H7 on a lab-on-a-chip. ZFPs custom-designed to detect Shiga toxin in E. coli O157:H7 were immobilized on a cyclic olefin copolymer (COC) chip, which can function as a non-PCR based molecular diagnostic device. Pathogen-specific double-stranded DNA was directly detected by using engineered ZFPs immobilized on the COC chip with high specificity, providing a detection limit of 10 fmol of target DNA in a colorimetric assay. Therefore, in this study, we demonstrated the great potential of ZFP arrays on the COC chip for further development of a simple and novel lab-on-a-chip technology for the detection of pathogens.
Direct detection of double-stranded DNA (dsDNA) using zinc finger proteins (ZFPs) is of great importance in biomedical applications such as identifying pathogens and circulating DNAs. However, its sensitivity is still not sufficiently high because limited signalling labels can be conjugated or fused. Herein, we report sensitive and direct detection of dsDNA using (i) alkaline phosphatase (ALP) as a fast catalytic label conjugated to ZFPs along with (ii) electrochemical measurement of an ALP product (l-ascorbic acid) at the indium-tin oxide electrode with a high signal-to-background ratio. ALP is simply conjugated to a ZFP through lysine residues in a ZFP purification tag, a maltose binding protein (MBP). Sandwich-type electrochemical detection of dsDNA allows a detection limit of ca. 100 fM without using DNA amplification.