Prior studies established constitutively active AP‐1, NF‐κB, and STAT3 signaling in oral cancer. Differential expression/activation of specific members of these transcription factors has been documented in HPV‐positive oral lesions that respond better to therapy. We performed a comprehensive analysis of differentially expressed, transcriptionally active members of these pivotal signaling mediators to develop specific signatures of HPV‐positive and HPV‐negative oral lesions by immunohistochemical method that is applicable in low‐resource settings. We examined a total of 31 prospective and 30 formalin‐fixed, paraffin‐embedded tissues from treatment‐naïve, histopathologically and clinically confirmed cases diagnosed as oral or oropharyngeal squamous cell carcinoma (OSCC/OPSCC). Following determination of their HPV status by GP5 + /GP6 +  PCR, the sequential sections of the tissues were evaluated for expression of JunB, JunD, c‐Fos, p50, p65, STAT3, and pSTAT3(Y705), along with two key regulatory proteins pEGFR and p16 by IHC. Independent analysis of JunB and p65 showed direct correlation with HPV positivity, whereas STAT3 and pSTAT3 were inversely correlated. A combined analysis of transcription factors revealed a more restrictive combination, characterized by the presence of AP‐1 and NF‐κB lacking involvement of STAT3 that strongly correlated with HPV‐positive tumors. Presence of STAT3/pSTAT3 with NF‐κB irrespective of the presence or absence of AP‐1 members was present in HPV‐negative lesions. Expression of pSTAT3 strongly correlated with all the AP‐1/NF‐κB members (except JunD), its upstream activator pEGFRY 1092, and HPV infection‐related negative regulator p16. Overall, we show a simple combination of AP‐1, NF‐κB, and STAT3 members’ expression that may serve as molecular signature of HPV‐positive lesions or more broadly the tumors that show better prognosis.

Viral oncoproteins E6/E7 play key oncogenic role in human papillomavirus (HPV)-mediated cervical carcinogenesis in conjunction with aberrant activation of cellular signaling events. GLI-signaling has been implicated in metastasis and tumor recurrence of cervical cancer. However, the interaction of GLI-signaling with HPV oncogenes is unknown. We examined this relationship in established HPV-positive and HPV-negative cervical cancer cell lines using specific GLI inhibitor, cyclopamine and HPVE6/E7 siRNAs. Cervical cancer cell lines showed variable expression of GLI-signaling components. HPV16-positive SiHa cells, overexpressed GLI1, Smo and Patch. Inhibition by cyclopamine resulted in dose-dependent reduction of Smo and GLI1 and loss of cell viability with a higher magnitude in HPV-positive cells. Cyclopamine selectively downregulated HPVE6 expression and resulted in p53 accumulation, whereas HPVE7 and pRb level remained unaffected. siRNA-mediated silencing of HPV16E6 demonstrated reduced GLI1 transcripts in SiHa cells. Cervical cancer stem-like cells isolated by side population analysis, displayed retention of E6 and GLI1 expression. Fraction of SP cells was reduced in cyclopamine-treated cultures. When combined with E6-silencing cyclopamine resulted in loss of SP cell’s sphere-forming ability. Co-inhibition of GLI1 and E6 in cervical cancer cells showed additive anti-cancer effects. Overall, our data show existence of a cooperative interaction between GLI signaling and HPVE6.

Antibiotic resistance is one of our most serious global health threats. The adverse effects of overusing and misusing antibiotics are highly publicized in the health professional literature. Antibiotic abuse occurs during routine endodontic treatment and there are deficiencies in knowledge regarding prescribing antibiotic and appropriate prophylactic antibiotic use. Multidisciplinary coordination and cooperation among dentists, pharmacists, and patients is needed to curb antibiotic abuse. As endodontists, we can become part of the solution to the antibiotic resistance crisis and deal with it conclusively. This review article discusses antibiotic resistance resulting from antibiotic abuse during endodontic treatment, various factors contributing to it, and measures required for stopping antibiotic abuse in endodontic treatment. A web-based research on MedLine was performed with terms Review Articles published in the last 10 year's dental journals in English for literature researching, extracting, and synthesizing data. Relevant articles were shortlisted. Important cross-reference articles were also reviewed.

Background Angiogenic switch is a hallmark feature of transition from low-grade to high-grade cervical intraepithelial neoplasia (CIN) in cervical cancer progression. Therefore, early events leading to locally-advanced cervical metastatic lesions demand a greater understanding of the underlying mechanisms. Recent leads indicate the role of tumor-derived exosomes in altering the functions of endothelial cells in cervical cancer, which needs further investigation. Methods Exosomes isolated from cervical cancer cell lines were assessed for their angiogenic effect on the human umbilical vein endothelial cells (HUVEC) using tube formation and wound healing assay. The exosomal uptake by HUVEC cells was monitored using PKH-67 labelling followed by fluorescence microscopy. Alterations in Hh-GLI signaling components, PTCH1 and GLI1, in HUVEC were measured by immunoblotting. Changes in angiogenesis-related transcripts of vascular endothelial growth factor VEGF-A, VEGF-B, VEGFR2 and angiopoietin-1, angiopoietin-2, osteopontin were measured in exosome-treated HUVEC and in the exosomal RNA by RT-PCR. Results Enhanced tube formation, with an increased number of nodes and branching was observed in HUVEC’s treated with exosomes derived from different cervical cancer cell lines. HPV-positive (SiHa and HeLa) cells’ exosomes were more angiogenic. Exosome-treated HUVEC showed increased migration rate. PKH-67 labelled exosomes were found internalized in HUVEC. A high level of PTCH1 protein was detected in the exosome—treated endothelial cells. Subsequent RT-PCR analysis showed increased transcripts of Hh-GLI downstream target genes VEGF-A, VEGFR2, angiopoietin-2, and decreased expression of VEGF-B, and angiopoietin-1, suggestive of active Hh-GLI signaling. These effects were more pronounced in HUVEC’s treated with exosomes of HPV-positive cells. However, these effects were independent of tumor-derived VEGF-A as exosomal cargo lacked VEGF-A transcripts or proteins. Conclusion Overall, the data showed cervical cancer exosomes promote pro-angiogenic response in endothelial cells via upregulation of Hh-GLI signaling and modulate downstream angiogenesis-related target genes. The study provides a novel exosome-mediated mechanism potentially favoring cervical angiogenesis and thus identifies the exosomes as potential pharmacological targets against locally-advanced metastatic cervical lesions. Graphic abstract