Squamous Cell Carcinoma Cells Research Articles

Loss of CELF2 promotes skin tumorigenesis and increases drug resistance.

CELF2 belongs to the CELF RNA-binding protein family and exhibits antitumor activity in various tumor models. Analysis of the pan-cancer TCGA database reveals that CELF2 expression strongly correlates with favorable prognosis among cancer patients. The function of CELF2 in nonmelanoma skin cancer has not been studied. We used shRNA-mediated knockdown (KD) of CELF2 expression in human squamous cell carcinoma (SCC) cells to investigate how CELF2 impacted SCC cell proliferation, survival, and xenograft tumor growth. We determined CELF2 expression in human SCC tissues and adjacent normal skin using immunofluorescence staining. Additionally, we investigated the changes in CELF2 and its target gene expression during UV-induced and chemical-induced skin tumorigenesis by western blotting. CELF2 KD significantly increased SCC cell proliferation, colony growth, and SCC xenograft tumor growth in immunodeficient mice. CELF2 KD in SCC cells led to activation of KRT80 and GDF15, which can potentially promote cell proliferation and tumor growth. While control SCC cells were sensitive to anticancer drugs such as doxorubicin, SCC cells with CELF2 KD became resistant to drug-induced tumor growth retardation. Finally, we found CELF2 expression diminished during both UV- and chemical-induced skin tumorigenesis in mice, consistent with reduced CELF2 expression in human SCC tumors compared to adjacent normal skin. This study shows for the first time that CELF2 loss occurs during skin tumorigenesis and increases drug resistance in SCC cells, highlighting the possibility of targeting CELF2-regulated pathways in skin cancer prevention and therapies.

Potential treatment of squamous cell carcinoma by targeting heparin-binding protein 17/fibroblast growth factor-binding protein 1 with vitamin D3 or eldecalcitol.

Heparin-binding protein 17 (HBp17), first purified in 1991 from the conditioned medium of the human A431 squamous cell carcinoma (SCC) cell line, was later renamed fibroblast growth factor-binding protein 1 (FGFBP-1). HBp17/FGFBP-1 is specifically expressed and secreted by epithelial cells, and it reversibly binds to fibroblast growth factor (FGF)-1 and FGF-2, as well as FGFs-7, -10, and -22, indicating a crucial involvement in the transportation and function of these FGFs. Our laboratory has investigated and reported several studies to elucidate the function of HBp17/FGFBP-1 in SCC cells and its potential as a molecular therapeutic target. HBp17/FGFBP-1 transgene exoression in A431-4 cells, a clonal subline of A431 that lacks tumorigenicity and does not express HBp17/FGFBP-1, demonstrated a significantly enhanced proliferation in vitro compared with A431-4 cells, and it acquired tumorigenicity in the subcutis of nude mice. Knockout (KO) of the HBp17/FGFBP-1 by genome editing significantly suppressed tumor growth, cell motility, and tumorigenicity compared with control cells. A comprehensive analysis of expressed molecules in both cell types revealed that molecules that promote epithelial cell differentiation were highly expressed in HBp17/FGFBP-1 KO cells. Additionally, we reported that 1α,25(OH)2D3 or eldecalcitol (ED-71), which is an analog of 1α,25(OH)2D3, suppresses HBp17/FGFBP-1 expression and tumor growth in vitro and in vivo by inhibiting the nuclear factor kappa-light-chain-enhancer of activated B cells signaling pathway. Here, we discuss the prospects of molecular targeted therapy targeting HBp17/FGFBP-1 with 1α,25(OH)2D3 or ED71 in SCC and oral SCC.

Epithelial-mesenchymal transition in oral cancer cells induced by prolonged and persistent Fusobacterium nucleatum stimulation

ObjectivesSeveral studies have reported the effects of Fusobacterium nucleatum stimulation on oral cancer cells. However, given that these studies typically span a stimulation period of three days to eight days, the in vitro studies conducted to date may not fully mimic the oral cancer environment, which involves constant exposure to oral commensal bacteria. This study aimed to elucidate the effects of prolonged and persistent Fusobacterium nucleatum infection on oral cancer cells. MethodsHuman tongue squamous cell carcinoma (SCC) cells were continuously stimulated with Fusobacterium nucleatum for two or four weeks, then experimentally evaluated. ResultsProlonged, persistent Fusobacterium nucleatum stimulation increased the cells’ proliferative, invasive, and migratory capacities, decreased their expression of epithelial markers, and increased their expression of mesenchymal markers progressively with time. The cells also adopted a spindle-shaped morphology and cell-to-cell contact dependence was progressively lost, suggesting time-dependent occurrence of epithelial-mesenchymal transition. Furthermore, mRNA levels of CD44, a cancer stem cell marker, were time-dependently upregulated. When SCC cells were stimulated with Fusobacterium nucleatum for four weeks in the presence of dexamethasone, Fusobacterium nucleatum induced epithelial-mesenchymal transition was inhibited. ConclusionsEpithelial-mesenchymal transition in human tongue SCC cells was time-dependently induced by prolonged, persistent Fusobacterium nucleatum stimulation and inhibited by dexamethasone. Routine decontamination of the oral cavity may be crucial for controlling tumor invasion and metastasis.

Interleukin 33 supports squamous cell carcinoma growth via a dual effect on tumour proliferation, migration and invasion, and T cell activation

Interleukin (IL)-33 is an important cytokine in the tumour microenvironment; it is known to promote the growth and metastasis of solid cancers, such as gastric, colorectal, ovarian and breast cancer. Our group demonstrated that the IL-33/ST2 pathway enhances the development of squamous cell carcinoma (SCC). Conversely, other researchers have reported that IL-33 inhibits tumour progression. In addition, the crosstalk between IL-33, cancer cells and immune cells in SCC remains unknown. The aim of this study was to investigate the effect of IL-33 on the biology of head and neck SCC lines and to evaluate the impact of IL-33 neutralisation on the T cell response in a preclinical model of SCC. First, we identified epithelial and peritumoural cells as a major local source of IL-33 in human SCC samples. Next, in vitro experiments demonstrated that the addition of IL-33 significantly increased the proliferative index, motility and invasiveness of SCC-25 cells, and downregulated MYC gene expression in SCC cell lines. Finally, IL-33 blockade significantly delayed SCC growth and led to a marked decrease in the severity of skin lesions. Importantly, anti-IL-33 monoclonal antibody therapy increase the percentage of CD4+IFNγ+ T cells and decreased CD4+ and CD8+ T cells secreting IL-4 in tumour-draining lymph nodes. Together, these data suggest that the IL-33/ST2 pathway may be involved in the crosstalk between the tumour and immune cells by modulating the phenotype of head and neck SCC and T cell activity. IL-33 neutralisation may offer a novel therapeutic strategy for SCC.

Genetic correlation and causal associations between psychiatric disorders and lung cancer risk

BackgroundPatients with certain psychiatric disorders have increased lung cancer incidence. However, establishing a causal relationship through traditional epidemiological methods poses challenges. MethodsAvailable summary statistics of genome-wide association studies of cigarette smoking, lung cancer, and eight psychiatric disorders, including attention deficit/hyperactivity disorder (ADHD), autism, depression, major depressive disorder, bipolar disorder, insomnia, neuroticism, and schizophrenia (range N: 46,350-1,331,010) were leveraged to estimate genetic correlations using Linkage Disequilibrium Score Regression and assess causal effect of each psychiatric disorder on lung cancer using two-sample Mendelian randomization (MR) models, comprising inverse-variance weighted (IVW), weighted median, MR-Egger, pleiotropy residual sum and outlier testing (MR-PRESSO), and a constrained maximum likelihood approach (cML-MR). ResultsSignificant positive correlations were observed between each psychiatric disorder and both smoking and lung cancer (all FDR < 0.05), except for the correlation between autism and lung cancer. Both univariable and the cML-MA MR analyses demonstrated that liability to schizophrenia, depression, ADHD, or insomnia was associated with an increased risk of overall lung cancer. Genetic liability to insomnia was linked specifically to squamous cell carcinoma (SCC), while genetic liability to ADHD was associated with an elevated risk of both SCC and small cell lung cancer (all P < 0.05). The later was further supported by multivariable MR analyses, which accounted for smoking. LimitationsParticipants were constrained to European ancestry populations. Causal estimates from binary psychiatric disorders may be biased. ConclusionOur findings suggest appropriate management of several psychiatric disorders, particularly ADHD, may potentially reduce the risk of developing lung cancer.

The Ability of Clinically Relevant Chemotherapeutics to Induce Immunogenic Cell Death in Squamous Cell Carcinoma.

Immunogenic cell death (ICD) is a crucial mechanism for triggering the adaptive immune response in cancer patients. Damage-associated molecular patterns (DAMPs) are critical factors in the detection of ICD. Chemotherapeutic drugs can cause ICD and the release of DAMPs. The aim of this study was to assess the potential for paclitaxel and platinum-based chemotherapy regimens to induce ICD in squamous cell carcinoma (SCC) cell lines. In addition, we examined the immunostimulatory effects of clinically relevant chemotherapeutic regimens utilized in the treatment of SCC. We screened for differentially expressed ICD markers in the supernatants of three SCC cell lines following treatment with various chemotherapeutic agents. The ICD markers included Adenosine Triphosphate (ATP), Calreticulin (CRT), Annexin A1 (ANXA 1), High Mobility Group Protein B1 (HMGB1), and Heat Shock Protein 70 (HSP70). A vaccination assay was also employed in C57BL/6J mice to validate our in vitro findings. Lastly, the levels of CRT and HMGB1 were evaluated in Serum samples from SCC patients. Addition of the chemotherapy drugs cisplatin (DDP), carboplatin (CBP), nedaplatin (NDP), oxaliplatin (OXA) and docetaxel (DOC) increased the release of ICD markers in two of the SCC cell lines. Furthermore, mice that received vaccinations with cervical cancer cells treated with DDP, CBP, NDP, OXA, or DOC remained tumor-free. Although CBP induced the release of ICD-associated molecules in vitro, it did not prevent tumor growth at the vaccination site in 40% of mice. In addition, both in vitro and in vivo results showed that paclitaxel (TAX) and LBP did not induce ICD in SCC cells. The present findings suggest that chemotherapeutic agents can induce an adjuvant effect leading to the extracellular release of DAMPs. Of the agents tested here, DDP, CBP, NDP, OXA and DOC had the ability to act as inducers of ICD.

Pleckstrin Homology Domain Leucine-rich Repeat Protein Phosphatase Acts as a Tumor Suppressor in Oral Squamous Cell Carcinoma.

The pleckstrin homology domain leucine-rich repeat protein phosphatase (PHLPP) family has been found to have both tumor-suppressor and oncogenic properties across various types and locations of cancer. Given that PHLPP has not been previously studied in oral squamous cell carcinoma (SCC), we conducted an assessment of the expression of both its isoforms in oral SCC tissues and cell lines and compared these findings to their corresponding normal counterparts. In addition, we assessed the relationship between PHLPP and clinicopathological factors and patient survival. Quantitative real-time polymerase chain reaction was used to detect the mRNA levels of PHLPP1 and PHLPP2 in cancerous and normal cell lines in addition to 124 oral SCC and noncancerous adjacent epithelia (N = 62, each). Correlations between their expression rate and clinicopathological parameters were further evaluated in 57 patients. Data were statistically analyzed with t test and paired t test, analysis of variance, Mann-Whitney U , and Cox Regression tests ( P < 0.05). We found significantly lower levels of both PHLPP isoforms in oral SCC tissues compared with noncancerous epithelia ( P < 0.001, for both). However, in the cell lines, this difference was significant only for PHLPP1 ( P = 0.027). The correlation between the two isoforms was significant only in cancerous tissues ( P < 0.001). None of the clinicopathologic factors showed significant associations with either of the isoforms and there was no correlation with survival. We showed for the first time that PHLPP1 and PHLPP2 act as tumor suppressors in oral SCC at the mRNA level. The regulation of their mRNA appears to be different between normal and cancerous tissues.

Complex and variable regulation of ΔNp63 and TAp63 by TGFβ has implications for the dynamics of squamous cell epithelial to mesenchymal transition

TGFβ has roles in inflammation, wound healing, epithelial to mesenchymal transition (EMT), and cancer stem cell states, and acts as a tumor suppressor gene for squamous cell carcinoma (SCC). SCCs are also characterized by high levels of ΔNp63, which induces epithelial cell phenotypes and maintains squamous stem cells. Previous studies indicate a complex interplay between ΔNp63 and TGFβ signaling, with contradictory effects reported. We investigated the effects of TGFβ on p63 isoform proteins and mRNAs in non-malignant squamous and SCC cells, and the role of either canonical or non-canonical TGFβ signaling pathways. TGFβ selectively increased ΔNp63 protein levels in non-malignant keratinocytes in association with SMAD3 activation and was prevented by TGFβ receptor inhibition, indicating activation of canonical TGFβ pathway signaling. TP63 isoform mRNAs showed discordance from protein levels, with an initial increase in both TAP63 and ΔNP63 mRNAs followed by a decrease at later times. These data demonstrate complex and heterogeneous effects of TGFβ in squamous cells that depend on the extent of canonical TGFβ pathway aberrations. The interplay between TGFβ and p63 is likely to influence the magnitude of EMT states in SCC, with clinical implications for tumor progression and response to therapy.

Abstract 2798: Oral fungal infection tweaks the innate immune tumor microenvironment promoting

Abstract It is yet unknown how a fungus and tumor interplay impairs innate immunity, modulating tumorigenesis. Here, we found that oral infection with Cladosporium cladosporioides of mice with Ikka deficiency in epithelial stem cells enhanced STAT3-dependent oral squamous cell carcinoma (SCC) development and fungal colonization. In wild-type mice infection was cleared up, suggesting a synergic tumor-fungus loop involved in the accelerated carcinogenesis. C. cladosporioides-mediated EGFR activation stimulated intratumor STAT3-led pathways to generate an acidic oral milieu, which disrupted bacterial compositions and suppressed neutrophil’s ROS but increased Il1b expression, dampening neutrophil’s fungitoxicity and allowing oral fungal and bacterial overgrowth. In addition, fungus-induced IL-1β/IL-17A augmented STAT3 activity in SCC cells, contributing to local and distal carcinogenesis. Significantly, fungal signals were greater in human head and neck SCCs (HNSCCs) and SCC-adjacent tissues than in healthy controls and were co-localized with IL1B-expressing neutrophils in HNSCCs. These similar traits of oncogenic pathways, microbiota dysbiosis, and defective neutrophils in HNSCC patients with poor survival highlight the importance of increased fungal infection for human malignant development and therapy. Citation Format: Xin Li, Na-Young Song, Amit Kumar Singh, Jonathan Badger, Chengfei Jiang, Feng Zhu, Debra Tross, Yongmei Zhao, Bao Tran, Yinling Hu. Oral fungal infection tweaks the innate immune tumor microenvironment promoting [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2798.

Abstract 1990: TIP60-mediated acetylation of ΔNp63α is associated with cisplatin resistance

Abstract The chemotherapeutic drug Cisplatin is often used to treat squamous cell carcinoma (SCC) patients, but low response rates and disease recurrence are common. About 5.4 million basal and squamous cell skin cancers are diagnosed each year in the US. ΔNp63α, a member of the p53 family of transcription factors, is overexpressed and considered oncogenic in non-melanoma skin cancer where it regulates cell survival, promotes proliferation, and inhibits cell apoptosis. ΔNp63α has also been shown to promote resistance to cisplatin by orchestrating the transcriptional regulation of several DNA damage response (DDR) genes. Our previous study showed that the histone acetyltransferase (HAT) TIP60 promotes SCC proliferation by positively regulating ΔNp63α protein levels in a manner reliant on the catalytic activity of TIP60. This observation suggested that TIP60 may contribute to the failure of platinum-based drugs in SCC and led us to hypothesize that TIP60-mediated acetylation of ΔNp63α regulates its stability and transcriptional activity to promote chemoresistance. We found that TIP60 levels positively correlated with ΔNp63α stability, protein levels, and cisplatin resistance. Further, silencing endogenous TIP60 led to a decrease in ΔNp63α transcript and protein levels in multiple cisplatin resistant SCC cell lines. Further, stable expression of TIP60 or ΔNp63α individually promoted resistance to cisplatin and reduced cell death, whereas loss of ΔNp63α or TIP60 induced G2/M arrest, increased cell death, and sensitized cells to cisplatin. Additionally, pharmacological inhibition of TIP60 reduced acetylation of ΔNp63α, decreased colony formation, and sensitized resistant cells to cisplatin. Finally, we demonstrated that ΔNp63α and TIP60 levels positively correlated with DNA repair capacity and negatively correlated with cisplatin-DNA adduct formation. Silencing of either TIP60 or ΔNp63α intensified cisplatin-DNA adduct formation and significantly reduced the expression of drug efflux transporters. Taken together, our data indicate that TIP60-mediated stabilization of ΔNp63α increases cisplatin resistance and provides critical insights into the mechanisms by which ΔNp63α confers cisplatin resistance in SCC. Our findings suggest that the inhibition of TIP60 may be therapeutically advantageous in overcoming cisplatin resistance in SCC and other epithelial cancers. Citation Format: Akshay Hira, Jin Zhang, Mike Kemp, Madhavi P. Kadakia. TIP60-mediated acetylation of ΔNp63α is associated with cisplatin resistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1990.

Reciprocal inhibition between TP63 and STAT1 regulates anti-tumor immune response through interferon-γ signaling in squamous cancer

Squamous cell carcinomas (SCCs) are common and aggressive malignancies. Immune check point blockade (ICB) therapy using PD-1/PD-L1 antibodies has been approved in several types of advanced SCCs. However, low response rate and treatment resistance are common. Improving the efficacy of ICB therapy requires better understanding of the mechanism of immune evasion. Here, we identify that the SCC-master transcription factor TP63 suppresses interferon-γ (IFNγ) signaling. TP63 inhibition leads to increased CD8+ T cell infiltration and heighten tumor killing in in vivo syngeneic mouse model and ex vivo co-culture system, respectively. Moreover, expression of TP63 is negatively correlated with CD8+ T cell infiltration and activation in patients with SCC. Silencing of TP63 enhances the anti-tumor efficacy of PD-1 blockade by promoting CD8+ T cell infiltration and functionality. Mechanistically, TP63 and STAT1 mutually suppress each other to regulate the IFNγ signaling by co-occupying and co-regulating their own promoters and enhancers. Together, our findings elucidate a tumor-extrinsic function of TP63 in promoting immune evasion of SCC cells. Over-expression of TP63 may serve as a biomarker predicting the outcome of SCC patients treated with ICB therapy, and targeting TP63/STAT/IFNγ axis may enhance the efficacy of ICB therapy for this deadly cancer.

MicroRNA expression profiling of cutaneous squamous cell carcinomas and precursor lesions

AbstractBackgroundActinic keratoses (AK) are pre‐malignant skin lesions caused by chronic sun exposure. Progression from an AK to intraepidermal carcinoma (IEC) and a cutaneous squamous cell carcinoma (SCC) is well known but the rate of transformation to an invasive SCC is highly variable. Since no definitive biomarkers are available, treatment decisions are made ad hoc.ObjectivesTo fully characterise our AK to SCC progression series, we performed microRNA (miRNA) microarray expression profiling of normal and photodamaged skin, as well as AKs, IEC, and invasive SCCs.MethodsThe study recruited 27 patients who donated fresh biopsies of normal skin, photodamaged skin, AK, IEC, and SCC (n = 67 specimens). All miRbase (v.21) miRNAs were profiled to identify miRNAs related to SCC progression. miRNAs were validated using qRT‐PCR and in vitro phenotypic assays.ResultsThere were 234 robustly expressed miRNAs across the tissue collection, which resulted in 20 miRNA that were differentially expressed ((cor)p ≤ 0.05 and ≥ 10 fold) between normal skin and SCC. Hierarchical clustering all samples illustrated that AKs, IEC, and SCCs were largely indistinguishable, which confirms the premalignant status of an AK. A panel of miRNAs showed significant dysregulation between normal and photodamaged skin and AK. Importantly, we found miR‐34a‐5p and miR‐31‐5p had significant differential expression between AKs and IEC and IEC and SCC respectively. Phenotypic assays determined that the miR‐31 duplex had opposing effects on SCC cell lines which suggests that dysregulation of this duplex may be related to the dynamic control of progression of transformed keratinocytes.ConclusionsThis study confirmed the continuum of AK with IEC and SCC highlighting that miRNA expression plays a role in keratinocyte transformation. Development of our putative miRNA biomarker candidates is warranted to aid in clinical management of patients experiencing high AK load to determine the most appropriate treatment.

Histology and Lung Nodule Fluorescence in Intraoperative Molecular Imaging With Pafolacianine

BackgroundIntraoperative molecular imaging (IMI) uses a cancer-targeted fluorescent agent injected into patients to localize tumor nodules. Pafolacianine is a folate receptor (FR)–targeted near-infrared fluorescent probe. Almost 10% of patients have false negative fluorescence findings intraoperatively. We hypothesized that tumor histology explains why lung cancer may not fluoresce. MethodsAdenocarcinoma (AC) (A549, LKR) and squamous cell carcinoma (SCC) (H127, H1264) cell lines were stained with pafolacianine. Near-infrared fluorescent microscopy was used to quantify mean fluorescence intensity. Tissue microarray slides of patients with AC and SCC were evaluated by immunohistochemistry for FR alpha (FRα) and beta (FRβ) expression. Finally, we retrospectively analyzed IMI data from clinical trials of patients with AC and SCC receiving pafolacianine. ResultsAC (intensity 30.31) cell lines have a higher fluorescence intensity than SCC cell lines (intensity 5.4) (P < .001). On slide analysis, 93.8% of ACs expressed FRα compared with 44.4% of SCCs (P = .002). Finally, there were 326 patients enrolled in clinical trials: 211 had lesions localized in vivo, and 134 of these patients had pure AC or SCC. All 9 patients with SCC have a positive smoking history and a mean pack-year of 60.2 (SD 3,6), whereas 76% of patients with AC have a history of smoking and a mean pack-year of 29.3 (P = .02). The odds ratio for fluorescence of (AC/SCC) was 2.05 (P = .004) and 2.01 (P = .02) on univariate and multivariate logistic regression, respectively. ConclusionsDuring IMI with pafolacianine, a nonfluorescent nodule is more likely to be SCC than AC. AC has a high probability of fluorescing because of higher expression of FRα or FRβ, or both.

MiR-184 represses β-catenin and behaves as a skin tumor suppressor

miR-184-knockout mice display perturbed epidermal stem cell differentiation. However, the potential role of miR-184 in skin pathology is unclear. Here, we report that miR-184 controls epidermal stem cell dynamics and that miR-184 ablation enhances skin carcinogenesis in mice. In agreement, repression of miR-184 in human squamous cell carcinoma (SCC) enhances neoplastic hallmarks of human SCC cells in vitro and tumor development in vivo. Characterization of miR-184-regulatory network, suggests that miR-184 inhibits pro-oncogenic pathways, cell proliferation, and epithelial to mesenchymal transformation. Of note, depletion of miR-184 enhances the levels of β-catenin under homeostasis and following experimental skin carcinogenesis. Finally, the repression of β-catenin by miR-184, inhibits the neoplastic phenotype of SCC cells. Taken together, miR-184 behaves as an epidermal tumor suppressor, and may provide a potentially useful target for skin SCC therapy.

Genetic correlation and causal associations between circulating C-reactive protein levels and lung cancer risk.

We aimed to characterize genetic correlations and causal associations between circulating C-reactive protein (CRP) levels and the risk of lung cancer (LC). Leveraging summary statistics from genome-wide association studies of circulating CRP levels among 575,531 individuals of European ancestry, and LC risk among 29,266 cases and 56,450 controls, we investigated genetic associations of circulating CRP levels with the risk of overall lung cancer and its histological subtypes, by using linkage disequilibrium score (LDSC) regression and Mendelian randomization (MR) analyses. Significant positive genetic correlations between circulating CRP levels and the risk of LC and its histological subtypes were identified from LDSC regression, with correlation coefficients ranging from 0.12 to 0.26, and all false discovery adjusted p < 0.05. Univariable MR demonstrated a nominal association between CRP levels and an increased risk of lung squamous cell carcinoma (SCC) (inverse variance-weighted OR = 1.15, 95% CI 1.01-1.30). However, this association disappeared when multivariable MR included cigarettes per day and/or body mass index. By using our recently developed constrained maximum likelihood-based MR method, we identified significant associations of CRP levels with the risk of overall LC (OR 1.06, 95% CI 1.03-1.09), SCC (OR 1.06, 95% CI 1.02-1.09), and small cell lung cancer (SCLC, OR 1.09, 95% CI 1.03-1.15). Moreover, most univariable and multivariable MR analyses also revealed consistent CRP-SCLC associations. There may be a genetic and causal association between circulating CRP levels and the risk of SCLC, which is in line with previous population-based observational studies.

Anti-cancer effects of green synthesized gold nanoparticles using leaf extract of Annona muricata. L against squamous cell carcinoma cell line 15 through apoptotic pathway

Background: Oral cancer remains one of the most dreadful diseases in developing nations. Currently, there has been a rise in the prevalence of tongue squamous cell carcinoma (SCC), with a poor prognosis. The use of standard treatment approaches against oral cancer patients brings about several side effects. In recent years, nanomedicine has provided a versatile platform for developing new targeted therapeutic modalities. However, safety remains a concern in the synthesis of nanoparticles (NPs). Therefore, the present study aims to synthesize safer phytoconstituent-mediated gold NPs (AuNPs) utilizing leaf extracts of Annona muricata, where the biochemical components of the plant leaf act as the reducing and capping agents in the synthesis of NPs, and to evaluate its anti-cancer activity against SCC. Materials and Methods: In this in vitro experimental study, AuNPs were synthesized through an effective, simple, and ecologically sound green synthesis method. After characterization of these synthesized AuNPs, in vitro assays such as 3-(4, 5-dimethylthiazole2-yl)-2, 5-biphenyl tetrazolium bromide, wound healing, and clonogenic assays were carried out to investigate the anti-cancer potential of green synthesized AuNPs in the human tongue SCC cell line (SCC-15), and the possible mechanism of action was evaluated through gene and protein expression analysis of Bax, Bcl-2, and p53 genes. The results were expressed as mean ± standard deviation using Statistical Package for Social Sciences (SPSS) 20.0 software and Student's t-test was performed for experimental data. P ≤0.05 were considered statistically significant. Results: The in vitro assays demonstrated that the synthesized AuNPs are exhibiting anti-cancer activity by apoptosis of SCC-15 cells in a dose-dependent manner. Further, it also revealed a highly significant decrease in anti-apoptotic Bcl-2 gene expression, whereas pro-apoptotic genes p53 and Bax revealed a highly significant increase, which is statistically significant compared to the control (P &lt; 0.05). Conclusion: Our findings demonstrated that the AuNPs synthesized from A. muricata leaf extract could act as a novel anticancer agent, particularly against SCC, after further scrutiny.

Expression Analysis of Retinal G Protein-coupled Receptor and its Correlation with Regulation of the Balance between Proliferation and Aberrant Differentiation in Cutaneous Squamous Cell Carcinoma.

Retinal G protein-coupled receptor (RGR), a photosensitive protein, functions as a retinal photoisomerase under light conditions in humans. Cutaneous squamous cell carcinoma (cSCC) is linked to chronic ultraviolet exposure, which suggests that the photoreceptor RGR may be associated with tumorigenesis and progression of squamous cell carcinoma (SCC). However, the expression and function of RGR remain uncharacterized in SCC. This study analysed RGR expression in normal skin and in lesions of actinic keratosis, Bowen's disease and invasive SCC of the skin with respect to SCC initiation and development. A total of 237 samples (normal skin (n = 28), actinic keratosis (n = 42), Bowen's (n = 35) and invasive SCC (n = 132) lesions) were examined using immunohistochemistry. Invasive SCC samples had higher expression of RGR protein than the other samples. A high immunohistochemical score for RGR was associated with increased tumour size, tumour depth, Clark level, factor classification, and degree of differentiation and a more aggressive histological subtype. In addition, RGR expression was inversely correlated with involucrin expression and positively correlated with proliferating cell nuclear antigen (PCNA) and Ki67 expression. Furthermore, RGR regulates SCC cell differentiation through the PI3K-Akt signalling pathway, as determined using molecular biology approaches in vitro, suggesting that high expression of RGR is associated with aberrant proliferation and differentiation in SCC.

Novel nanoparticle AuNCs conjugated with Desmoglein-3 antibody for FL/CT dual-mode targeted imaging and precise treatment of lung squamous cell carcinoma

Due to lack of effective, early and non-invasive diagnostic as well as treatment tools, the surgical treatment opportunities for lung squamous cell carcinoma (SCC) are limited, resulting in high mortality rates. Therefore, the combination of targeted recognition and precise treatment of lung SCC is of great significance. In this study, a multifunctional nanoparticle is designed and synthesized, which specifically identifies lung SCC cells for target imaging and therapy. Desmoglein-3 (Dsg-3), a transmembrane glycoprotein found in desmosomes, is highly expressed in lung SCC cells. Gold nanoclusters (AuNCs) conjugated with Dsg-3 antibodies to form Au-Dsg-3 through coupling reaction. The results showed that the fluorescence imaging (FI) intensity and computed tomography (CT) signal of Au-Dsg-3 significantly increased within 6 h in vitro and in vivo, achieving dual-modal imaging to detect lung SCC effectively. Besides, Au-Dsg-3 even integrates targeted photothermal therapy (PTT) characteristics in a single nanoparticle. When exposed to near-infrared radiation (NIR), the temperature of the tumor site increased rapidly and reached a high temperature of 53.3 °C after 600 s, causing tumor ablation and growth inhibition. In summary, Au-Dsg-3 provides a key platform for targeted biological imaging and collaborative PTT, which demonstrates good performance on lung SCC.

Comparative analysis of immune infiltrates in head and neck cancers across anatomical sites

BackgroundThe response rate to immune checkpoint inhibitors targeting programmed cell death 1 (PD-1) receptor is 13%–18% for patients with recurrent or metastatic head and neck squamous cell carcinoma (HNSCC). Detailed...

Acrolein suppresses anticancer drug-induced toxicity mediated by activating claudin-1 and Nrf2 axis in a spheroid model of human lung squamous cell carcinoma cells

Tobacco smoke contains various carcinogenic ingredients such as nicotine, acrolein, and benzopyrene; however, their effects on cancer treatment are not fully understood. Claudin-1 (CLDN1), a component of tight junctions, is involved in the increased resistance to anticancer drugs. In this study, we found that acrolein increases the mRNA and protein levels of CLDN1 in RERF-LC-AI cells derived from human lung squamous cell carcinoma (SCC). Acrolein increased the p-extracellular signal-regulated kinase (ERK) 1/2 levels without affecting the p-Akt level. The acrolein-induced elevation of CLDN1 expression was attenuated by U0126, a mitogen-activated protein kinase kinas (MEK) inhibitor. These results indicate that the activation of MEK/ERK pathway is involved in the acrolein-induced elevation of CLDN1 expression. In a spheroid model, acrolein suppressed the accumulation and toxicity of doxorubicin (DXR), which were rescued by CLDN1 silencing. The acrolein-induced effects were also observed in lung SCC-derived EBC-1 and LK-2 cells. Acrolein also increased the expression level of nuclear factor erythroid 2-related factor 2 (Nrf2), a transcription factor that regulates antioxidant and detoxifying genes, which were inhibited by CLDN1 silencing. In spheroid cells, the levels of reactive oxygen species were enhanced by acrolein, which was inhibited by CLDN1 silencing. Taken together, acrolein may reduce the anticancer drug-induced toxicity in human lung SCC cells mediated by high CLDN1 expression followed by the upregulation of Nrf2 signaling pathway.