Persistently elevated soluble MHC class I polypeptide-related sequence A and transforming growth factor-β1 levels are poor prognostic factors in head and neck squamous cell carcinoma after definitive chemoradiotherapy

PDK1- and PDK2-mediated metabolic reprogramming contributes to the TGFβ1-promoted stem-like properties in head and neck cancer

BACKGROUND

Resistance to chemotherapeutic drugs is a key factor for cancer recurrence and metastases in head and neck cancer (HNC). Cancer stem cells (CSCs) in tumors have self-renewal, differentiation, and higher drug resistance capabilities, resulting in a poor prognosis for patients. In glucose metabolism, pyruvate dehydrogenase kinase (PDK) inhibits pyruvate dehydrogenase and impedes pyruvate from being metabolized into acetyl-CoA and entering the tricarboxylic acid cycle to generate energy. Studies have reported that PDK1 and PDK2 inhibition suppresses the growth, motility, and drug resistance of cancer cells. Furthermore, while TGFβ1 levels are persistently elevated in HNC patients with poor prognosis, the role of PDK isoforms in the TGFβ1-promoted progression and stem-like properties of HNC is unclear.

METHODS

Levels of PDK1 and PDK2 were evaluated in HNC tissue microarrays by immunohistochemistry to explore potential clinical relevance. PDK1 and PDK2 were knocked down by the lentivirus shRNA system to investigate their role in TGFβ1-promoted tumor progression in vitro.

RESULTS

We found that PDK2 levels were increased in the later stage of HNC tissues compared to constant PDK1 expression. After PDK1 and PDK2 knockdown, we discovered increased ATP production and decreased lactate production in TGFβ1-treated and untreated HNC cells. However, only PDK2 silencing significantly inhibited the clonogenic ability of HNC cells. We subsequently found that TGFβ1-promoted migration and invasion capabilities were decreased in PDK1 and PDK2 knockdown cells. The tumor spheroid-forming capability, motility, CSC genes, and multidrug-resistant genes were downregulated in PDK1 and PDK2 silencing CSCs. PDK1 and PDK2 inhibition reversed cisplatin and gemcitabine resistance of CSCs, but not paclitaxel resistance.

CONCLUSION

The results demonstrated that the PDK1- and PDK2-mediated Warburg effect contributes to the TGFβ1-enhanced stemness properties of HNC. Therefore, PDK1 and PDK2 may serve as molecular targets for the combination therapy of HNC.

Assessing tumor angiogenesis using dynamic contrast-enhanced integrated magnetic resonance-positron emission tomography in patients with non-small-cell lung cancer

Background

Angiogenesis assessment is important for personalized therapeutic intervention in patients with non-small-cell lung cancer (NSCLC). This study investigated whether radiologic parameters obtained by dynamic contrast-enhanced (DCE)-integrated magnetic resonance-positron emission tomography (MR-PET) could be used to quantitatively assess tumor angiogenesis in NSCLC.

Methods

This prospective cohort study included 75 patients with NSCLC who underwent DCE-integrated MR-PET at diagnosis. The following parameters were analyzed: metabolic tumor volume (MTV), maximum standardized uptake value (SUV_max), reverse reflux rate constant (k_ep), volume transfer constant (K^trans), blood plasma volume fraction (v_p), extracellular extravascular volume fraction (v_e), apparent diffusion coefficient (ADC), and initial area under the time-to-signal intensity curve at 60 s post enhancement (iAUC₆₀). Serum biomarkers of tumor angiogenesis, including vascular endothelial growth factor-A (VEGF-A), angiogenin, and angiopoietin-1, were measured by enzyme-linked immunosorbent assays simultaneously.

Results

Serum VEGF-A (p = 0.002), angiogenin (p = 0.023), and Ang-1 (p <  0.001) concentrations were significantly elevated in NSCLC patients compared with healthy individuals. MR-PET parameters, including MTV, K^trans, and k_ep, showed strong linear correlations (p <  0.001) with serum angiogenesis-related biomarkers. Serum VEGF-A concentrations (p = 0.004), MTV values (p <  0.001), and k_ep values (p = 0.029) were significantly higher in patients with advanced-stage disease (stage III or IV) than in those with early-stage disease (stage I or II). Patients with initial higher values of angiogenesis-related MR-PET parameters, including MTV > 30 cm³ (p = 0.046), K^trans > 200 10^− 3/min (p = 0.069), and k_ep > 900 10^− 3/min (p = 0.048), may have benefited from angiogenesis inhibitor therapy, which thus led to significantly longer overall survival.

Conclusions

The present findings suggest that DCE-integrated MR-PET provides a reliable, non-invasive, quantitative assessment of tumor angiogenesis; can guide the use of angiogenesis inhibitors toward longer survival; and will play an important role in the personalized treatment of NSCLC.

Oral cancer cell‑derived exosomes modulate natural killer cell activity by regulating the receptors on these cells

Oral cancer (OC) is the most common type of head and neck malignant tumor. Tumor‑derived exosomes induce a complex extracellular environment that affects tumor immunity. In the present study, exosomes were isolated from OC cell lines (WSU‑HN4 and SCC‑9) by ultrafiltration and the protein content of these oral cancer‑derived exosomes (OCEXs) was analyzed by mass spectrometry, which revealed the enrichment of transforming growth factor (TGF)‑β1. Natural killer (NK) cells were examined by flow cytometry following co‑culture with OCEXs. The expression of killer cell lectin like receptor K1 (KLRK1; also known as NKG2D, as used herein) and natural cytotoxicity triggering receptor 3 (NCR3; also known as NKp30, as used herein) in NK cells was found to be significantly upregulated following co‑culture with the OCEXs for 1 day, whereas this expression decreased at 7 days. Killer cell lectin like receptor C1 (KLRC1; also known as NKG2A; as used herein) expression exhibited an opposite trend at 1 day. In addition, NK cell cytotoxicity against the OC cells was enhanced at 1 day, but was attenuated at 7 days. TGF‑β1 inhibited the function of NK cells at 7 days, whereas it had no obvious effects at 1 and 3 days. On the whole, the findings of the present study reveal changes in NK cell function and provide new insight into NK cell dysfunction.

Overexpression of lncRNA snaR is correlated with progression and predicts poor survival of laryngeal squamous cell carcinoma

Long noncoding RNAs (lncRNA) snaR is a characterized oncogenic lncRNA in triple negative breast cancer and ovarian cancer, while its role in other human diseases is unknown. In the present study, we found that plasma levels of snaR were upregulated in patients with laryngeal squamous cell carcinoma (LSCC) than in healthy controls. Plasma levels of snaR increased with increase in AJCC stages. Follow-up study showed that high plasma levels of snaR were correlated with poor overall survival. Plasma levels of snaR were positively correlated with transforming growth factor beta (TGF-β1) in patients with LSCC but not in healthy controls. Overexpression of snaR resulted in upregulation of TGF-β1 in cells of human LSCC cell lines, while exogenous TGF-β1 treatment showed no significant effect on snaR expression. snaR overexpression and exogenous TGF-β1 treatment promoted LSCC cell proliferation, migration, and invasion. In addition, TGF-β inhibitor partially reduced the enhancing effects of snaR overexpression on LSCC cell proliferation, migration, and invasion. Therefore, overexpression of lncRNA snaR is correlated with progression and predicts poor survival of LSCC and the mechanism of its actions is likely related to TGF-β1.