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Growth hormone inducible transmembrane protein (GHITM), one member of Bax inhibitory protein‐like family, has been rarely studied, and the clinical importance and biological functions of GHITM in kidney renal clear cell carcinoma (KIRC) still remain unknown. In the present study, we found that GHITM was downregulated in KIRC. Aberrant GHITM downregulation related to clinicopathological feature and unfavourable prognosis of KIRC patients. GHITM overexpression inhibited KIRC cell proliferation, migration and invasion in vitro and in vivo. Mechanistically, GHITM overexpression could induce the downregulation of Notch1, which acts as an oncogene in KIRC. Overexpression of Notch1 effectively rescued the inhibitory effect induced by GHITM upregulation. More importantly, GHITM could regulate PD‐L1 protein abundance and ectopic overexpression of GHITM enhanced the antitumour efficiency of PD‐1 blockade in KIRC, which provided new insights into antitumour therapy. Furthermore, we also showed that YY1 could decrease GHITM level via binding to its promoter. Taken together, our study revealed that GHITM was a promising therapeutic target for KIRC, which could modulate malignant phenotype and sensitivity to PD‐1 blockade of renal cancer cells via Notch signalling pathway. [ABSTRACT FROM AUTHOR]

Although combination chemotherapy is widely used for bladder cancer (BC) treatment, the recurrence and progression rates remain high. Therefore, novel therapeutic targets are required. Methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) contributes to tumourigenesis and immune evasion in several cancers; however, its biological function in BC remains unknown. This study aimed to investigate the expression, prognostic value and protumoural function of MTHFD2 in BC and elucidate the mechanism of programmed death‐ligand 1 (PD‐L1) upregulation by MTHFD2. An analysis using publicly available databases revealed that a high MTHFD2 expression was correlated with clinical features and a poor prognosis in BC. Furthermore, MTHFD2 promoted the growth, migration, invasion and tumourigenicity and decreased the apoptosis of BC cells in vivo and in vitro. The results obtained from databases showed that MTHFD2 expression was correlated with immune infiltration levels, PD‐L1 expression, and the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. The expression of MTHFD2, PD‐L1 and JAK/STAT signalling pathway‐related proteins increased after interferon gamma treatment and decreased after MTHFD2 knockdown. Moreover, addition of a JAK/STAT pathway activator partially reduced the effect of MTHFD2 knockdown on BC cells. Collectively, our findings suggest that MTHFD2 promotes the expression of PD‐L1 through the JAK/STAT signalling pathway in BC. [ABSTRACT FROM AUTHOR]

Soft tissue sarcoma (STS) is an uncommon malignancy that often carries a grim prognosis. Trophinin‐associated protein (TROAP) is augmented in a variety of tumors and can affect tumor proliferation. Nevertheless, the prognostic value and specific functions of TROAP in STS are still vague. Herein, we display that TROAP exhibits an augmented trend in STS, and its elevation correlates with a poor prognosis of STS. Furthermore, its reduction is related to increased immune cell infiltration, enhanced stroma, and elevation of immune activation. Meanwhile, the TROAP‐derived genomic signature is validated to predict patient prognosis, immunotherapy, and drug response reliably. A nomogram constructed based on age, metastatic status, and a TROAP‐derived risk score of an STS individual could be used to quantify the survival probability of STS. In addition, in vitro experiments have demonstrated that TROAP is overexpressed in STS, and the downregulation of TROAP could affect the proliferation, migration, metastasis, and cell cycle of STS cells. In summary, the TROAP expression is elevated in STS tissues and cells, which is related to the poor prognosis and malignant biological behaviors of STS. It could act as a potential prognostic biomarker for diagnosis and treatment of STS. [ABSTRACT FROM AUTHOR]

Background: Great progress has been made in studying the function of long non‐coding RNA (lncRNA) in various tumors, including gastric cancer (GC). However, there are still numerous lncRNAs that have not yet been studied and explored for their roles in GC, and their important functions need to be further revealed. Methods: Through analyzing The Cancer Genome Atlas (TCGA) database combined with bioinformatics survival tools, a novel GC‐related lncRNA LGALS8‐AS1 was identified. A quantitative real‐time polymerase chain reaction and a series of in vitro or in vivo cell functional experiments were performed to determine the expression and the role of LGALS8‐AS1/miR‐138‐5p/PLAGL2 in GC. Results: LGALS8‐AS1 was remarkably upregulated and correlated with the unfavorable prognosis in GC. Higher expression of LGALS8‐AS1 was positively associated with higher lymph node metastasis rate, as well as larger tumor size. In addition, a series of cell functional experiments revealed that LGALS8‐AS1 could facilitate GC cell proliferation, migration and metastasis in vitro or in vivo. A deeper mechanism exploration revealed that LGALS8‐AS1 could function as the miR‐138‐5p molecular sponge and upregulate the PLAGL2 expression, thereby promoting the cell proliferation, migration and metastasis in GC. Conclusions: In brief, we revealed the tumor promoting role of the LGALS8‐AS1/miR‐138‐5p/PLAGL2 molecular signaling axis in GC, and our findings provide enlightenment for further understanding of the mechanism of tumorigenesis and development of GC, making LGALS8‐AS1 a possible new diagnostic or therapeutic target for GC. [ABSTRACT FROM AUTHOR]

Gastric cancer is the second leading cause of cancer deaths worldwide, and more understanding of its molecular basis is urgently needed. Gastric gland mucin secreted from pyloric gland cells, mucous neck cells, and cardiac gland cells of the gastric mucosa harbors unique O‐glycans carrying terminal α1,4‐linked N‐acetylglucosamine (αGlcNAc) residues. We previously reported that αGlcNAc loss correlated positively with poor outcomes for patients with differentiated‐type gastric cancer. However, the molecular mechanisms underlying these outcomes remained poorly understood. Here, we examined the effects of upregulated αGlcNAc expression on malignant phenotypes of the differentiated‐type gastric cancer cell lines, AGS and MKN7. Upregulation of αGlcNAc following ectopic expression of its biosynthetic enzyme attenuated cell proliferation, motility, and invasiveness of AGS and MKN7 cells in vitro. Moreover, AGS cell tumorigenicity was significantly suppressed by αGlcNAc overexpression in a xenograft model. To define the molecular mechanisms underlying these phenotypes, we investigated αGlcNAc binding proteins in AGS cells and identified Mucin‐1 (MUC1) and podocalyxin. Both proteins were colocalized with αGlcNAc on human gastric cancer cells. We also found that αGlcNAc was bound to MUC1 in murine normal gastric mucosa. When we assessed the effects of αGlcNAc binding to MUC1, we found that αGlcNAc blocked galectin‐3 binding to MUC1, phosphorylation of the MUC1 C‐terminus, and recruitment of Src and β‐catenin to that C‐terminus. These results suggest that αGlcNAc regulates cancer cell phenotypes by dampening MUC1 signal transduction. [ABSTRACT FROM AUTHOR]

Biomarkers for early diagnosis of pancreatic cancer are greatly needed, as the high fatality of this cancer is in part due to delayed detection. α1,4‐linked N‐acetylglucosamine (αGlcNAc), a unique O‐glycan specific to gastric gland mucus, is biosynthesized by α1,4‐N‐acetylglucosaminyltransferase (α4GnT) and primarily bound at the terminal glycosylated residue to scaffold protein MUC6. We previously reported that αGlcNAc expression decreases at early stages of neoplastic pancreatic lesions, followed by decreased MUC6 expression, although functional effects of these outcomes were unknown. Here, we ectopically expressed α4GnT, the αGlcNAc biosynthetic enzyme, together with MUC6 in the human pancreatic cancer cell lines MIA PaCa‐2 and PANC‐1, neither of which expresses α4GnT and MUC6. We observed significantly suppressed proliferation in both lines following coexpression of α4GnT and MUC6. Moreover, cellular motility decreased following MUC6 ectopic expression, an effect enhanced by cotransduction with α4GnT. MUC6 expression also attenuated invasiveness of both lines relative to controls, and this effect was also enhanced by additional α4GnT expression. We found αGlcNAc‐bound MUC6 formed a complex with trefoil factor 2. Furthermore, analysis of survival curves of patients with pancreatic ductal adenocarcinoma using a gene expression database showed that samples marked by higher A4GNT or MUC6 mRNA levels were associated with relatively favorable prognosis. These results strongly suggest that αGlcNAc and MUC6 function as tumor suppressors in pancreatic cancer and that decreased expression of both may serve as a biomarker of tumor progression to pancreatic cancer. [ABSTRACT FROM AUTHOR]

Background: Glucosylceramidase (GBA) mutations are considered the most common genetic risk factors for developing Parkinson's disease (PD). Objectives: We aimed to assess, at different time points, the integrity of brain striatal and extra‐striatal dopamine pathways and clinical phenotype of a group of PD subjects bearing heterozygous GBA mutations (GBA‐PD), compared with a group of idiopathic PD patients (iPD) stratified by age at disease onset. A longitudinal approach was adopted to evaluate the progression over time for clinical and 123I‐FP‐CIT SPECT imaging features. Methods: We considered 46 GBA‐PD patients and 339 iPD patients, subdivided into two groups according to age at PD onset (n = 58 < 50 years and n = 281 > 50 years). We measured differences in the occurrence/severity/progression of motor and non‐motor features, 123I‐FP‐CIT standard uptake value ratios (SUVr) in striatal and extra‐striatal regions, and global cognitive deterioration over time in a subset of 168 cases with available follow‐up. Results: At baseline, the GBA‐PD cohort showed more severe motor and cognitive deficits than the early‐iPD cohort. The 123I‐FP‐CIT SUVr reduction in the striatal and the extra‐striatal regions was more marked in the GBA‐PD than the early‐ and late‐iPD cohorts. Both GBA‐PD and late‐iPD patients had a significant annual deterioration in their global cognitive performance, while the early‐iPD group showed global cognitive stability over time. At follow‐up, the iPD cohorts became similar to the GBA‐PD group in 123I‐FP‐CIT SUVr reduction. Conclusion: These new findings support the hypothesis of a biological role of GBA mutations in accelerating the early neurodegenerative processes in PD, leading to the malignant clinical phenotype. © 2021 International Parkinson and Movement Disorder Society [ABSTRACT FROM AUTHOR]

Aims: Experimental evidence demonstrated a crucial role of TROAP (Trophinin‐associated protein) in regulating the cell proliferation of multiple tumors, while TROAP expression and function were largely unknown in glioma. We aimed to investigate the oncogenic role of TROAP and its potential mechanisms in gliomagenesis. Methods: Four gene expression databases (GEO, TCGA, GTEx and CCLE) were enrolled in our study and used for TROAP expression and survival analysis. TROAP expression was quantified by qRT‐PCR, western blot and immunohistochemistry assays in glioma tissues and cell lines. TROAP knockdown and overexpression vector were constructed and transfected into glioma cells. CCK‐8, colony formation, transwell, and wound healing assays were used to evaluate cell viability, migration and invasion, flow cytometry to determine cell cycle arrest. Gene set enrichment analysis (GSEA) was conducted to screen the pathway involved in TROAP‐high phenotype. The expression of cell cycle and Wnt/β‐Catenin signaling proteins were analyzed by immunofluorescence and western blot. Results: Based on the bioinformatic analysis and a series of functional assays, we found the TROAP was enriched in glioma tissues and cell lines, its overexpression was correlated with the clinicopathologic characteristics and poor prognosis. TROAP knockdown inhibited cell proliferation, migration, invasion, and G1/S cell cycle arrest compared with control group in glioma. Mechanism analysis revealed that TROAP activated Wnt/β‐Catenin pathway and upregulated its downstream targets expression, while silencing β‐Catenin or Axin2 could reverse the tumor‐promoting effects caused by TROAP, confirming that TROAP‐induced malignant phenotype and tumorigenesis via Wnt/β‐Catenin signaling pathway. Conclusion: The present study found that TROAP accelerated the progression of gliomagenesis through Wnt/β‐Catenin pathway, and TROAP might be considered as a novel target for glioma therapy. [ABSTRACT FROM AUTHOR]

Background & Aims: Recently, overexpression of the fibroblast growth factor receptor 3 (FGFR3) splice variants FGFR3‐IIIb and FGFR3‐IIIc was found in ~50% of hepatocellular carcinoma (HCC). Here, we aim to identify FGFR3‐IIIb/IIIc ligands, which drive the progression of HCC. Methods: FACS, MTT assay and/or growth curves served to identify the FGFR3‐IIIb/IIIc ligand being most effective to induce growth of hepatoma/hepatocarcinoma cell lines, established from human HCC. The most potent FGF was characterized regarding the expression levels in epithelial and stromal cells of liver and HCC and impact on neoangiogenesis, clonogenicity and invasive growth of hepatoma/hepatocarcinoma cells. Results: Among all FGFR3‐IIIb/IIIc ligands tested, FGF9 was the most potent growth factor for hepatoma/hepatocarcinoma cells. Replication and/or sprouting of blood/lymphendothelial cells was stimulated as well. FGF9 occurred mainly in stromal cells of unaltered liver but in epithelial cells of HCC. Every fifth HCC exhibited overexpressed FGF9 and frequent co‐upregulation of FGFR3‐IIIb/IIIc. In hepatoma/hepatocarcinoma cells FGF9 enhanced the capability for clonogenicity and disintegration of the blood and lymphatic endothelium, being most pronounced in cells overexpressing FGFR3‐IIIb or FGFR3‐IIIc, respectively. Any of the FGF9 effects in hepatoma/hepatocarcinoma cells was blocked completely by applying the FGFR1‐3‐specific tyrosine kinase inhibitor BGJ398 or siFGFR3, while siFGFR1/2/4 were mostly ineffective. Conclusions: FGF9 acts via FGFR3‐IIIb/IIIc to enhance growth and aggressiveness of HCC cells. Accordingly, blockade of the FGF9‐FGFR3‐IIIb/IIIc axis may be an efficient therapeutic option for HCC patients. [ABSTRACT FROM AUTHOR]

The leucine zipper downregulated in cancer 1 (LDOC1) has been proposed as a regulator of transcription and cell signaling. We have previously demonstrated that LDOC1 is differentially expressed in papillary thyroid carcinoma (PTC), this study was designed to characterize LDOC1 expression in thyroid follicle originated cancer tissues and to specifically evaluate its function in thyroid carcinogenesis. LDOC1 expression was performed in human normal thyroid and thyroid cancer. LDOC1 function was characterized, in two PTC cell lines (TPC1 and BCPAP), through the analysis of in vitro cell proliferation, apoptosis, migration, and invasion along with in vivo tumor xenograft growth. Transduced BCPAP cells were stimulated with tumor necrosis factor α, and the levels of nuclear P65, Bax, Bcl‐2, c‐Myc, and XIAP were assessed. A luciferase reporter assay was used to measure nuclear factor‐κB (NF‐κB) activity, and the functional connection between LDOC1 effect and NF‐κB activity was determined using a specific NF‐κB inhibitor. Our results revealed that LDOC1 was translocated from the nucleus to the cytoplasm in human thyroid cancer, and was significantly downregulated in PTC compared with normal thyroid. LDOC1 overexpression in TPC1 resulted in a significant suppression of the malignant phenotype, whereas LDOC1 ablation in BCPAP promoted this phenotype. Additional studies demonstrated that LDOC1 ablation facilitated nuclear P65 expression and NF‐κB activity. NF‐κB inhibition reversed the effects of LDOC1 ablation on proliferation, apoptosis, migration, and invasion. Our findings confirmed that LDOC1 is a novel therapeutic target in PTC and provides new insight into the role of LDOC1 in PTC progression, through NF‐κΒ signaling suppression. [ABSTRACT FROM AUTHOR]

Objective: Recently, the impact of microRNAs (miRNAs) has been identified in hepatocellular carcinoma (HCC), this study was designed to assess the effects of miR‐124‐3p and midazolam (MDZ) in HCC with the involvement of PIM‐1. Methods: HepG2 human HCC cells were selected for our study, which were treated with different concentrations of MDZ. The gain‐ and loss‐of‐function experiments were performed to elucidate the migration, invasion, proliferation, colony formation ability, cell cycle, and apoptosis of HepG2 cells upon treatment of MDZ, miR‐124‐3p mimics, or miR‐124‐3p inhibitor. The expression levels of miR‐124‐3p, PIM‐1, Bax, Bcl‐2, P21, and Ki‐67 in HepG2 cells were assessed by reverse transcription quantitative polymerase chain reaction and western blot analysis. Moreover, HepG2 cell growth in vivo was measured by subcutaneous tumorigenesis in nude mice, and the target relation between miR‐124‐3p and PIM‐1 was evaluated using dual luciferase reporter gene assay. Results: We have found that after treated with overexpression of miR‐124‐3p and MDZ, there exhibited elevated miR‐124‐3p, declined expression of PIM‐1, attenuated migration, invasion, proliferation and colony formation ability, and promoted apoptosis of HepG2 cells. Additionally, it could be observed that the tumor volume and weight were all reduced upon treatment of overexpression of miR‐124‐3p and MDZ. Meanwhile, the results in the HepG2 cells that treated with down‐regulated miR‐124‐3p were the opposite. Furthermore, PIM‐1 was found to be a target gene of miR‐124‐3p. Conclusion: Our study found that MDZ could inhibit proliferation and accelerate apoptosis of HCC cells by elevation of miR‐124‐3p and suppressing PIM‐1, which may be an effective method in the treatment of HCC. [ABSTRACT FROM AUTHOR]

In malignant transformation, cellular stress‐response pathways are dynamically mobilized to counterbalance oncogenic activity, keeping cancer cells viable. Therapeutic disruption of this vulnerable homeostasis might change the outcome of many human cancers, particularly those for which no effective therapy is available. Here, we report the use of fibroblast growth factor 2 (FGF2) to demonstrate that further mitogenic activation disrupts cellular homeostasis and strongly sensitizes cancer cells to stress‐targeted therapeutic inhibitors. We show that FGF2 enhanced replication and proteotoxic stresses in a K‐Ras‐driven murine cancer cell model, and combinations of FGF2 and proteasome or DNA damage response‐checkpoint inhibitors triggered cell death. CRISPR/Cas9‐mediated K‐Ras depletion suppressed the malignant phenotype and prevented these synergic toxicities in these murine cells. Moreover, in a panel of human Ewing's sarcoma family tumor cells, sublethal concentrations of bortezomib (proteasome inhibitor) or VE‐821 (ATR inhibitor) induced cell death when combined with FGF2. Sustained MAPK‐ERK1/2 overactivation induced by FGF2 appears to underlie these synthetic lethalities, as late pharmacological inhibition of this pathway restored cell homeostasis and prevented these described synergies. Our results highlight how mitotic signaling pathways which are frequently overridden in malignant transformation might be exploited to disrupt the robustness of cancer cells, ultimately sensitizing them to stress‐targeted therapies. This approach provides a new therapeutic rationale for human cancers, with important implications for tumors still lacking effective treatment, and for those that frequently relapse after treatment with available therapies. We designed an unexplored approach to cancer therapy: mitogenic overstimulation to increase dependence on stress‐response pathways, plus stress‐targeted inhibitors to selectively kill cancer cells. As a proof of principle, we show that exogenous FGF2 enhanced replication and proteotoxic stresses in different cancer cell lines, rendering these cells prone to massive cell death when combined with ATR or proteasome inhibitors. [ABSTRACT FROM AUTHOR]

Several studies have shown an important role for long non‐coding RNA (lncRNA) in breast cancer progression. The present study investigated the role of lncRNA Opa interacting protein 5‐antisense RNA 1 (OIP5‐AS1) in the progression of breast cancer. OIP5‐AS1 was significantly upregulated in breast cancer tissues and in breast cancer cell lines, and OIP5‐AS1 downregulation inhibited the malignant behavior of breast cancer in vitro and in vivo. For in‐depth exploration of the mechanism of OIP5‐AS1 in breast cancer, we found that expression of microRNA‐129‐5p(miR‐129‐5p), which was found to bind sites in the sequence of OIP5‐AS1, in breast cancer tissues was negatively correlated with OIP5‐AS1. Also, luciferase assays indicated that OIP5‐AS1 acted as a miR‐129‐5p sponge, resulting in upregulated expression of the sex‐determining region Y‐box 2 (SOX2) transcription factor. Our study showed that OIP5‐AS1 plays a critical role in promoting breast cancer progression and that OIP5‐AS1 downregulation targets SOX2 by miR‐129‐5p upregulation. lncRNA OIP5‐AS1 promotes breast cancer malignant phenotype. 2. lncRNA OIP5‐AS1 acts as ceRNA, targeting SOX2 by regulating miR‐129‐5p. [ABSTRACT FROM AUTHOR]

Numerous studies have reported that the role played by miR-26a in cancer is controversial, but whether miR-26a regulates metadherin (MTDH) expression in esophageal squamous cell carcinoma (ESCC) is unclear. We performed this study to investigate the clinical relevance of miR-26a expression in ESCC. miR-26a was detected by using the in situ hybridization method. To functionally analyze the role of miR-26a in ESCC cell lines in vitro, KYSE-450 and Eca109 cells were employed, whose endogenous miR-26a was artificially down- or up-regulated, respectively, by using lentiviral-based transfection. There was significant association between miR-26a expression and clinical stage (P = 0.049), lymph node metastasis (P = 0.023), tumor volume (P = 0.003), and poor overall prognosis (P = 0.026). miR-26a was able to suppress proliferation and migration of ESCC cells in vitro. Moreover, we have confirmed that miR-26a can negatively regulate MTDH in ESCC cells by using luciferase reporter assay. In addition, to investigate the role miR-26a plays in cell proliferation, we nude mice were xenografted with ESCC cells whose miR-26a was stably down- and up-regulated. Together, our results show that miR-26a is capable of suppressing the proliferation and migration of ESCC cells via negative regulation of MTDH. Moreover, miR-26a expression was clinically relevant in cancer progression and poor prognosis, which supports the idea that miR-26a acts as a tumor suppressor in ESCC.--Yang, C., Zheng, S., Liu, T., Liu, Q., Dai, F., Zhou, J., Chen, Y., Sheyhidin, I., Lu, X. Down-regulated miR-26a promotes proliferation, migration, and invasion via negative regulation of MTDH in esophageal squamous cell carcinoma. [ABSTRACT FROM AUTHOR]

One characteristic of solid tumors such as malignant melanoma is the acidification of the tumor microenvironment. The deregulation of cancer cell metabolism is considered a main cause of extracellular acidosis. Here, cancer cells utilize aerobic glycolysis instead of oxidative phosphorylation even under normoxic conditions, as originally described by Otto Warburg. These metabolic alterations cause enhanced acid production, especially of lactate and carbon dioxide ( CO2). The extensive production of acidic metabolites and the enhanced acid export to the extracellular space cause a consistent acidification of the tumor microenvironment, thus promoting the formation of an acid-resistant tumor cell population with increased invasive and metastatic potential. As melanoma is one of the deadliest and most metastatic forms of cancer, understanding the effects of this extracellular acidosis on human melanoma cells with distinct metastatic properties is important. The aim of this review was to summarize recent studies of the acidification of the tumor microenvironment, focusing on the specific effects of the acidic milieu on melanoma cells and to give a short overview of therapeutic approaches. [ABSTRACT FROM AUTHOR]

CD147 overexpresses in many epithelium-originated tumors and plays an important role in tumor migration and invasion. Most studies aim at the role of CD147 in tumor progression using tumor cell models. However, the influence of abnormal overexpression of CD147 on neoplastic transformation of normal cells is unknown. Here, the role of CD147 in malignant phenotype transformation in CHO cells was investigated. Three CHO cell lines that stably overexpressed CD147 (CHO-CD147), EGFP-CD147 (CHO-EGFP-CD147), and EGFP (CHO-EGFP) were generated by transfection of plasmids containing human CD147, EGFP-human CD147, and EGFP genes into CHO cells. Cell migration and invasion were detected by wound healing and transwell matrix penetration assay. Trypan blue exclusion, MTT, cell cycle analysis, and BrdU cell proliferation assay were used to detect cell viability and cell proliferation. Annexin V-FITC analysis was performed to detect apoptosis. We found that CD147 overexpression promoted the migration and invasion of CHO cells. CD147 accelerated the G1 to S phase transition and enhanced the CHO cell proliferation. Overexpression of CD147 inhibited both early- and late-stages of apoptosis of CHO-CD147 cells, which is caused by serum deprivation. CHO-EGFP-CD147 cells showed an increased anchorage-independent growth compared with CHO-EGFP cells as detected by soft-agar colony formation assay. The tumors formed by CHO-CD147 cells in nude mice were larger and coupled with higher expression of proliferating cell nuclear antigen and Ki-67 than that of CHO cells. In conclusion, human CD147 overexpression induces malignant phenotype in CHO cells. [ABSTRACT FROM AUTHOR]