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Purpose:The limited efficacy of chimeric antigen receptor (CAR) T-cell therapies with solid malignancies prompted us to test whether epigenetic therapy could enhance the antitumor activity of B7-H3.CAR T cells with several solid cancer types.Experimental Design:We evaluated B7-H3 expression in many human solid cancer and normal tissue samples. The efficacy of the combinatorial therapy with B7-H3.CAR T cells and the deacetylase inhibitor SAHA with several solid cancer types and the potential underlying mechanisms were characterized with in vitro and ex vivo experiments.Results:B7-H3 is expressed in most of the human solid tumor samples tested, but exhibits a restricted expression in normal tissues. B7-H3.CAR T cells selectively killed B7-H3 expressing human cancer cell lines in vitro. A low dose of SAHA upregulated B7-H3 expression in several types of solid cancer cells at the transcriptional level and B7-H3.CAR expression on human transgenic T-cell membrane. In contrast, the expression of immunosuppressive molecules, such as CTLA-4 and TET2, by T cells was downregulated upon SAHA treatment. A low dose of SAHA significantly enhanced the antitumor activity of B7-H3.CAR T cells with solid cancers in vitro and ex vivo, including orthotopic patient-derived xenograft and metastatic models treated with autologous CAR T-cell infusions.Conclusions:Our results show that our novel strategy which combines SAHA and B7-H3.CAR T cells enhances their therapeutic efficacy with solid cancers and justify its translation to a clinical setting.

Supplementary methods, tables and figures

Supplementary Data: Supplementary Materials and Methods, Supplementary Figures and Supplementary Tables.

Purpose:The overall biological roles and clinical significance of most long noncoding RNAs (lncRNA) in chemosensitivity are not fully understood. We investigated the biological function, mechanism, and clinical significance of lncRNA NR_034085, which we termed miRNA processing–related lncRNA (MPRL), in tongue squamous cell carcinoma (TSCC).Experimental Design:LncRNA expression in TSCC cell lines with cisplatin treatment was measured by lncRNA microarray and confirmed in TSCC tissues. The functional roles of MPRL were demonstrated by a series of in vitro and in vivo experiments. The miRNA profiles, RNA pull-down, RNA immunoprecipitation, serial deletion analysis, and luciferase analyses were used to investigate the potential mechanisms of MPRL.Results:We found that MPRL expression was significantly upregulated in TSCC cell lines treated with cisplatin and transactivated by E2F1. MPRL controlled mitochondrial fission and cisplatin sensitivity through miR–483-5p. In exploring the underlying interaction between MPRL and miR–483-5p, we identified that cytoplasmic MPRL directly binds to pre–miR–483 within the loop region and blocks pre–miR–483 recognition and cleavage by TRBP–DICER-complex, thereby inhibiting miR–483-5p generation and upregulating miR–483-5p downstream target-FIS1 expression. Furthermore, overexpression or knockdown MPRL altered tumor apoptosis and growth in mouse xenografts. Importantly, we found that high expression of MPRL and pre–miR–483, and low expression of miR–483-5p were significantly associated with neoadjuvant chemosensitivity and better TSCC patients’ prognosis.Conclusions:We propose a model in which lncRNAs impair microprocessor recognition and are efficient of pre-miRNA cropping. In addition, our study reveals a novel regulatory network for mitochondrial fission and chemosensitivity and new biomarkers for prediction of neoadjuvant chemosensitivity in TSCC.These findings uncover a novel mechanism by which lncRNA determines mitochondrial fission and cisplatin chemosensitivity by inhibition of pre-miRNA processing and provide for the first time the rationale for lncRNA and miRNA biogenesis for predicting chemosensitivity and patient clinical prognosis.

Supplementary Materials and Methods,Supplementary Figures and Supplementary Tables.

miRNAs that translocate from the nucleus to mitochondria are referred to as mitochondrial microRNAs (mitomiR). mitomiRs have been shown to modulate the translational activity of the mitochondrial genome, yet their role in mitochondrial DNA (mtDNA) transcription remains to be determined. Here we report that the mitomiR-2392 regulates chemoresistance in tongue squamous cell carcinoma (TSCC) cells by reprogramming metabolism via downregulation of oxidative phosphorylation and upregulation of glycolysis. These effects were mediated through partial inhibition of mtDNA transcription by mitomiR-2392 rather than through translational regulation. This repression required specific miRNA–mtDNA base pairing and Argonaute 2. mitomiR-2392 recognized target sequences in the H-strand and partially inhibited polycistronic mtDNA transcription in a cell-specific manner. A retrospective analysis of TSCC patient tumors revealed a significant association of miR-2392 and regulated mitochondrial gene expression with chemosensitivity and overall survival. The clinical relevance of targeted mitochondrial genes was consistently validated by The Cancer Genome Atlas RNA sequencing in multiple types of cancer. Our study revealed for the first time the role of mitomiR in mtDNA transcription and its contribution to the molecular basis of tumor cell metabolism and chemoresistance.Significance: These findings uncover a novel mechanism by which mitomiRNA regulates mitochondrial transcription and provide rationale for use of mitomiRNA and mtDNA-encoded genes to predict chemosensitivity and patient clinical prognosis.

Accumulating studies have proved that the circular RNAs (circRNAs) play vital roles in human cancers. However, few circRNAs have been elucidated with lymph node metastasis. This study demonstrated that circ-oral cancer metastasis-associated circRNA (circ-OMAC) is required to regulate the oral squamous cell carcinoma (OSCC) metastasis.The circ-OMAC were detected by circRNA-sequencing and further verified by in situ hybridization (ISH). The role of circ-OMAC was assessed by transwell assay and wound healing assay. Mechanistically, circ-OMAC regulated OSCC metastasis by initiating the epithelial-to-mesenchymal transition (EMT) signaling pathway.Our findings suggested that circ-OMAC was aberrantly elevated in the metastatic lymph nodes as compared to primary OSCC tissues. OSCC patients with high levels of circ-OMAC were prone to a poor prognosis. By developing functional assays, we confirmed that circ-OMAC promotes metastasis of OSCC cells via initiation of EMT pathways.We provide new insights whereby Circ-OMAC as an oncogene is a potential therapeutic target and prognostic marker in oral cancer.

Hypoexpression of human major histocompatibility complex (MHC) class I is widely known to be an important strategy of immune evasion in most cases of malignancies that lead to poor prognosis. We demonstrated that mitochondrial dynamics can be exploited as an efficient target in regulating MHC-I expression and cancer immunogenicity. Clinically, MHC-I expression and fragmentation of mitochondria are both closely associated to patient survival but are negatively correlated to one another. Mechanistically, it was observed that endoplasmic reticulum (ER) stress, an integrated signal transduction pathway activated in most rapidly proliferating tumor cells, played a crucial role in connecting mitochondrial fragmentation and cancer cell immunogenicity particularly via the IRE1α-XBP-1 s axis. XBP-1 s, which is activated by imbalanced mitochondrial fission and prolonged oxidative stress, served as a potent transcription factor, promoted the expression of aminopeptidase TPP2 and destructed the applicable antigenic peptide to impede MHC-I complex maturation and the activation of adaptive immune system upon cancer antigen. Our findings highlight the importance of mitochondrial dynamics in determining solid tumor immunogenicity and suggest that mediating mitochondrial fragmentation might provide a novel approach in anti-tumor immunotherapy.

Purpose: The limited efficacy of chimeric antigen receptor (CAR) T-cell therapies with solid malignancies prompted us to test whether epigenetic therapy could enhance the antitumor activity of B7-H3.CAR T cells with several solid cancer types. Experimental Design: We evaluated B7-H3 expression in many human solid cancer and normal tissue samples. The efficacy of the combinatorial therapy with B7-H3.CAR T cells and the deacetylase inhibitor SAHA with several solid cancer types and the potential underlying mechanisms were characterized with in vitro and ex vivo experiments. Results: B7-H3 is expressed in most of the human solid tumor samples tested, but exhibits a restricted expression in normal tissues. B7-H3.CAR T cells selectively killed B7-H3 expressing human cancer cell lines in vitro. A low dose of SAHA upregulated B7-H3 expression in several types of solid cancer cells at the transcriptional level and B7-H3.CAR expression on human transgenic T-cell membrane. In contrast, the expression of immunosuppressive molecules, such as CTLA-4 and TET2, by T cells was downregulated upon SAHA treatment. A low dose of SAHA significantly enhanced the antitumor activity of B7-H3.CAR T cells with solid cancers in vitro and ex vivo, including orthotopic patient-derived xenograft and metastatic models treated with autologous CAR T-cell infusions. Conclusions: Our results show that our novel strategy which combines SAHA and B7-H3.CAR T cells enhances their therapeutic efficacy with solid cancers and justify its translation to a clinical setting.

MicroRNAs (miRNAs) have been recently found in the mitochondria, and were named “mitomiRs”, but their function has remained elusive. Here, we aimed to assess the presence and function(s) of mitomiRs in tongue squamous cell carcinoma (TSCC). Methods: miRNA microarray was performed in paired TSCC cell lines, Cal27 and its chemoresistant counterpart, Cal27-re. Decreased expression of mitomiRs in chemoresistant cells was characterized. The functions of mitomiRs were investigated by a series of in vitro and in vivo experiments. Results: Differential microarray analysis identified downregulation of mitomiR-5787 in Cal27-re cells. We knocked down mitomiR-5787 in parental cells and upregulated its expression in cisplatin-resistant cells. The sensitivity of TSCC cells to cisplatin was regulated by miR-5787. The glucose metabolism assay suggested that reduced expression of miR-5787 changed the balance of glucose metabolism by shifting it from oxidative phosphorylation to aerobic glycolysis. Xenograft experiments in BALB/c-nu mice further verified the in vitro results. Reduced expression of miR-5787 contributes to chemoresistance in TSCC cells by inhibiting the translation of mitochondrial cytochrome c oxidase subunit 3 (MT-CO3). The prognostic analysis of 126 TSCC patients showed that the patients with low expression of miR-5787 and/or MT-CO3 had poor cisplatin sensitivity and prognosis. Conclusions: Mitochondrial miR-5787 could regulate cisplatin resistance of TSCC cells and affect oxidative phosphorylation and aerobic glycolysis. Downregulation of miR-5787 inhibited the translation of MT-CO3 to regulate cisplatin resistance of TSCC. Mitochondrial miR-5787 and MT-CO3 can be used as predictive biomarkers or therapeutic targets for cisplatin chemotherapy resistance.

Increasing evidence has shown that chemo-resistance is related to the process of epithelial-mesenchymal transition (EMT) and increased invasiveness by tongue squamous cell carcinoma (TSCC) cells. Long non-coding RNAs (lncRNAs) play pivotal roles in tumor metastasis and progression. However, the roles and mechanisms of lncRNAs in cisplatin-resistance-induced EMT and metastasis are not well understood. In this study, a chemotherapy-induced lncRNA 1 (CILA1) was discovered by using microarrays and was functionally identified as a regulator of chemo-sensitivity in TSCC cells. Upregulation of CILA1 promotes EMT, invasiveness, and chemo-resistance in TSCC cells, whereas the inhibition of CILA1 expression induces mesenchymal-epithelial transition (MET) and chemo-sensitivity, and inhibits the invasiveness of cisplatin-resistant cells both in vitro and in vivo. We also found that CILA1 exerts its functions via the activation of the Wnt/β-catenin signaling pathway. High CILA1 expression levels and low levels of phosphorylated β-catenin were closely associated with cisplatin resistance and advanced disease stage, and were predictors of poor prognosis in TSCC patients. These findings provided a new biomarker for the chemo-sensitivity of TSCC tumors and a therapeutic target for TSCC treatment.

BACKGROUND Harvesting an optimally thinned anterolateral thigh flaps is a challenge in overweight individuals and in the Western population. The authors describe a novel honeycomb technique to achieve a superthin anterolateral thigh flap in overweight patients. METHODS Forty patients with a body mass index greater than 25 kg/m(2) who required a thinned anterolateral thigh flap for reconstruction were assigned randomly to a honeycomb technique group or a microdissection technique group. The honeycomb technique group underwent flap thinning with the Cavitron Ultrasonic Surgical Aspirator, and flap thinning was performed with a conventional microdissection technique in the microdissection technique group. Perfusion of all flaps was measured by indocyanine green fluorescence angiography before and after thinning. Hypoperfusion was defined as 30 percent. RESULTS The mean body mass index was 28.6 ± 2.0 kg/m(2) and 27.3 ± 1.9 kg/m(2) in the honeycomb group and the microdissection group, respectively. Flap size, perforator, type of dissection, and initial perfusion were comparable between the two groups. However, significantly more patients (nine of 21) experienced final hypoperfusion in the microdissection group than in the honeycomb group (two of 19) (p = 0.034). In addition, blood loss and final flap thickness were significantly lower in the honeycomb group (p < 0.05), and the duration of thinning was comparable between the two groups. No flap necrosis was found in either group. CONCLUSION The honeycomb technique in combination with the Cavitron Ultrasonic Surgical Aspirator and indocyanine green angiography was able to remove adipose tissue but protect the integrity of the subcutaneous vascular plexus to reduce potential risk of jeopardizing flap perfusion while obtaining a superthin anterolateral thigh flap in an overweight population. CLINICAL QUESTION/LEVEL OF EVIDENCE Therapeutic, II.

A sub-population of chemoresistant cells exhibits biological properties similar to cancer stem cells (CSCs), and these cells are believed to be a main cause for tumor relapse and metastasis. In our study, we explored the role of SOX8 and its molecular mechanism in the regulation of the stemness properties and the epithelial mesenchymal transition (EMT) of cisplatin-resistant tongue squamous cell carcinoma (TSCC) cells. We found that SOX8 was upregulated in cisplatin-resistant TSCC cells, which displayed CSC-like properties and exhibited EMT. SOX8 was also overexpressed in chemoresistant patients with TSCC and was associated with higher lymph node metastasis, advanced tumor stage and shorter overall survival. Stable knockdown of SOX8 in cisplatin-resistant TSCC cells inhibited chemoresistance, tumorsphere formation, and EMT. The Wnt/β-catenin pathway mediated the cancer stem-like properties in cisplatin-resistant TSCC cells. Further studies showed that the transfection of active β-catenin in SOX8 stable-knockdown cells partly rescued the SOX8 silencing-induced repression of stem-like features and chemoresistance. Through chromatin immunoprecipitation and luciferase assays, we observed that SOX8 bound to the promoter region of Frizzled-7 (FZD7) and induced the FZD7-mediated activation of the Wnt/β-catenin pathway. In summary, SOX8 confers chemoresistance and stemness properties and mediates EMT processes in chemoresistant TSCC via the FZD7-mediated Wnt/β-catenin pathway.

Summary Cisplatin-based neoadjuvant chemotherapy has been shown to improve survival in patients with squamous cell carcinoma (SCC), but clinical biomarkers to predict chemosensitivity remain elusive. Here, we show the long noncoding RNA (lncRNA) LINC01011, which we termed cisplatin-sensitivity-associated lncRNA (CISAL), controls mitochondrial fission and cisplatin sensitivity by inhibiting BRCA1 transcription in tongue SCC (TSCC) models. Mechanistically, we found CISAL directly binds the BRCA1 promoter and forms an RNA-DNA triplex structure, sequestering BRCA1 transcription factor-GABPA away from the downstream regulatory binding region. Importantly, the clinical relevance of these findings is suggested by the significant association of CISAL and BRCA1 expression levels in TSCC tumors with neoadjuvant chemosensitivity and overall survival. We propose a new model where lncRNAs are tethered at gene promoter by RNA-DNA triplex formation, spatially sequestering transcription factors away from DNA-binding sites. Our study uncovers the potential of CISAL-BRCA1 signaling as a potential target to predict or improve chemosensitivity., Graphical Abstract, Highlights • CISAL enhances mitochondrial fission and cisplatin sensitivity in TSCC cells through BRCA1 • CISAL directly binds the BRCA1 promoter and forms an RNA-DNA triplex structure • CISAL sequesters GABPA away from regulatory binding at BRCA1 promoter • High CISAL predicts favorable neoadjuvant chemosensitivity and prognosis of TSCC patients, Biological Sciences; Molecular Biology; Cell Biology; Cancer

Purpose: The overall biological roles and clinical significance of most long noncoding RNAs (lncRNA) in chemosensitivity are not fully understood. We investigated the biological function, mechanism, and clinical significance of lncRNA NR_034085, which we termed miRNA processing–related lncRNA (MPRL), in tongue squamous cell carcinoma (TSCC). Experimental Design: LncRNA expression in TSCC cell lines with cisplatin treatment was measured by lncRNA microarray and confirmed in TSCC tissues. The functional roles of MPRL were demonstrated by a series of in vitro and in vivo experiments. The miRNA profiles, RNA pull-down, RNA immunoprecipitation, serial deletion analysis, and luciferase analyses were used to investigate the potential mechanisms of MPRL. Results: We found that MPRL expression was significantly upregulated in TSCC cell lines treated with cisplatin and transactivated by E2F1. MPRL controlled mitochondrial fission and cisplatin sensitivity through miR–483-5p. In exploring the underlying interaction between MPRL and miR–483-5p, we identified that cytoplasmic MPRL directly binds to pre–miR–483 within the loop region and blocks pre–miR–483 recognition and cleavage by TRBP–DICER-complex, thereby inhibiting miR–483-5p generation and upregulating miR–483-5p downstream target-FIS1 expression. Furthermore, overexpression or knockdown MPRL altered tumor apoptosis and growth in mouse xenografts. Importantly, we found that high expression of MPRL and pre–miR–483, and low expression of miR–483-5p were significantly associated with neoadjuvant chemosensitivity and better TSCC patients’ prognosis. Conclusions: We propose a model in which lncRNAs impair microprocessor recognition and are efficient of pre-miRNA cropping. In addition, our study reveals a novel regulatory network for mitochondrial fission and chemosensitivity and new biomarkers for prediction of neoadjuvant chemosensitivity in TSCC. These findings uncover a novel mechanism by which lncRNA determines mitochondrial fission and cisplatin chemosensitivity by inhibition of pre-miRNA processing and provide for the first time the rationale for lncRNA and miRNA biogenesis for predicting chemosensitivity and patient clinical prognosis.

A few modified approaches have been reported for performing endoscope-assisted dissections of benign parotid tumors, but none that use incisions totally hidden in a natural furrow. This study evaluated the feasibility of performing endoscope-assisted extracapsular dissections of benign parotid tumors using a single cephaloauricular furrow incision. Forty-six patients with benign parotid superficial lobe tumors were randomly divided into two groups: an endoscope-assisted (21 patients) group or a conventional (25 patients) surgery group. Perioperative and postoperative outcomes of the patients were evaluated, including the maximum diameter of the tumors, length of the incision, operating time, estimated blood loss during the operation, amount and duration of drainage, satisfaction scores based on the cosmetic results, perioperative complications, and follow-up information. The diameters of the tumors were comparable between the groups, and all operations were successfully performed as planned. The mean length of the incision in the endoscope-assisted group (3.6 ± 0.5 cm) was significantly shorter than that in the conventional group (9.1 ± 1.9). Meanwhile, the intraoperative blood loss, amount of drainage, perioperative complications, and cosmetic outcomes were all improved in the endoscope-assisted group. No tumor recurrence was found during 11–40 months of follow-up. Cephaloauricular furrow incisions were totally and naturally hidden in this procedure. Endoscope-assisted extracapsular dissections of benign parotid tumors via a small cephaloauricular furrow incision were found to be feasible and reliable, providing a minimally invasive approach and a satisfactory appearance.

miRNAs that translocate from the nucleus to mitochondria are referred to as mitochondrial microRNAs (mitomiR). mitomiRs have been shown to modulate the translational activity of the mitochondrial genome, yet their role in mitochondrial DNA (mtDNA) transcription remains to be determined. Here we report that the mitomiR-2392 regulates chemoresistance in tongue squamous cell carcinoma (TSCC) cells by reprogramming metabolism via downregulation of oxidative phosphorylation and upregulation of glycolysis. These effects were mediated through partial inhibition of mtDNA transcription by mitomiR-2392 rather than through translational regulation. This repression required specific miRNA–mtDNA base pairing and Argonaute 2. mitomiR-2392 recognized target sequences in the H-strand and partially inhibited polycistronic mtDNA transcription in a cell-specific manner. A retrospective analysis of TSCC patient tumors revealed a significant association of miR-2392 and regulated mitochondrial gene expression with chemosensitivity and overall survival. The clinical relevance of targeted mitochondrial genes was consistently validated by The Cancer Genome Atlas RNA sequencing in multiple types of cancer. Our study revealed for the first time the role of mitomiR in mtDNA transcription and its contribution to the molecular basis of tumor cell metabolism and chemoresistance. Significance: These findings uncover a novel mechanism by which mitomiRNA regulates mitochondrial transcription and provide rationale for use of mitomiRNA and mtDNA-encoded genes to predict chemosensitivity and patient clinical prognosis.

Neurotropic infiltrative growth and distant metastasis are the main causes of death in salivary adenoid cystic carcinoma (SACC) patients. Long noncoding RNAs (lncRNAs) are involved in many human neoplasms, however, their potential roles in SACC are unclear. In our study, we found that ADAM metallopeptidase with thrombospondin type 1 motif, 9 (ADAMTS9) antisense RNA 2 (ADAMTS9-AS2) was significantly upregulated in SACC patients with metastasis and SACC-lung metastasis (LM) cells. Moreover, ADAMTS9-AS2 expression was closely associated with the prognosis and distant metastasis in SACC patients. Next, we found that c-myc could specifically bind to the promoter of ADAMTS9-AS2 and activated its transcription. Knockdown of ADAMTS9-AS2 significantly inhibited migration and invasion of SACC cells in vitro and distant lung metastasis in vivo. Furthermore, ADAMTS9-AS2, which mainly expressed in the cytoplasm, shared microRNA (miRNA) response elements with Integrin α6 (ITGA6). Overexpression of ADAMTS9-AS2 competitively bound to miR-143-3p that inhibited ITGA6 from miRNA-mediated degradation, and thus it activated the activity of PI3K/Akt and MEK/Erk signaling and facilitated SACC metastasis. In summary, ADAMTS9-AS2 promotes migration and invasion in SACC by competing with miR-143-3p. This sheds a new insight into the regulation mechanism of ADAMTS9-AS2, and it provides a possible application for the SACC treatment.

BACKGROUND: Gnathodiaphyseal dysplasia (GDD) is a rare skeletal disorder that has not been well studied. METHODS: Sanger sequencing, whole-genome sequencing, and bioinformatics and structural modeling analyses were performed. RESULTS: A family with patients with fibro-osseous lesions of the jawbones were initially diagnosed with cherubism. Sequencing of SH3BP2, which is the causal gene of cherubism, revealed no pathogenic mutation. Through whole-genome sequencing, we identified a novel mutation c.1067G>T (p.C356F) in ANO5, and bioinformatics analyses and structural modeling showed that the mutation was deleterious. Because ANO5 is the gene responsible for GDD, we reappraised the clinical data of the patients, and the diagnosis was corrected to atypical GDD. A review of the literature showed that 67% of GDD cases confirmed by molecular testing were initially misdiagnosed. CONCLUSIONS: The novel mutation c.1067G>T (p.C356F) in ANO5 is responsible for the atypical GDD observed in our patients. GDD should be included in the differential diagnosis for patients with fibro-osseous lesions.