WNT/β-catenin pathway activation via Wnt1 overexpression and Axin1 downregulation correlates with cadherin-catenin complex disruption and increased lymph node involvement in micropapillary-predominant lung adenocarcinoma

LEF1 is associated with immunosuppressive microenvironment of patients with lung adenocarcinoma

Wnt/β-Catenin pathway plays an important role in the occurrence and progression of malignant tumors, especially PD-L1-mediated tumor immune evasion. However, the role of TCF/LEF, an important member of the Wnt/β-catenin pathway, in the tumor immunosuppressive microenvironment of lung adenocarcinoma (LUAD) remains unknown. LUAD tissue-coding RNA expression data from The Cancer Genome Atlas and TIMER databases were used to analyze the expression of TCF/LEF transcription factors and their correlation with various immune cell infiltration. Immunohistochemistry and immunofluorescence were used to detect tissue protein staining in 105 patients with LUAD. LEF1, TCF7, TCF7L1 and TCF7L2 were all aberrantly expressed in the tumor tissues of LUAD patients with the data from The Cancer Genome Atlas (TCGA) database, tumor immune estimation resource (TIMER) database and results of immunohistochemistry, but only LEF1 expression was associated with 5-year overall survival in LUAD patients. LEF1 protein expression was associated with advanced tumor node metastasis (TNM) stage, lymphatic metastasis and local invasion in 105 cases LUAD patients. At the same time, LEF1 mRNA expression was also associated with immunosuppressive microenvironment in LUAD patients with the data from TCGA database and TIMER database. Results of immunohistochemistry and immunofluorescence in tumor tissues of 105 cases LUAD patients showed that there was a positively correlation between LEF1 protein expression and the infiltration of M2 macrophages and Treg cells. LEF1 was highly expressed in tumor tissues of LUAD patients, and highly expressed LEF1 was associated with the immunosuppressive microenvironment of LUAD patients.

Wnt/β-catenin signaling in the development and therapeutic resistance of non-small cell lung cancer

Wnt/β-catenin signaling is a critical pathway that influences development and therapeutic response of non-small cell lung cancer (NSCLC). In recent years, many Wnt regulators, including proteins, miRNAs, lncRNAs, and circRNAs, have been found to promote or inhibit signaling by acting on Wnt proteins, receptors, signal transducers and transcriptional effectors. The identification of these regulators and their underlying molecular mechanisms provides important implications for how to target this pathway therapeutically. In this review, we summarize recent studies of Wnt regulators in the development and therapeutic response of NSCLC.

bHLH transcription factors Hes1, Ascl1 and Oligo2 exhibit different expression patterns in the process of physiological electric fields-induced neuronal differentiation

BACKGROUND

Recent studies have shown that the expression of bHLH transcription factors Hes1, Ascl1, and Oligo2 has an oscillating balance in neural stem cells (NSCs) to maintain their self-proliferation and multi-directional differentiation potential. This balance can be disrupted by exogenous stimulation. Our previous work has identified that electrical stimulation could induce neuronal differentiation of mouse NSCs.

METHODS

To further evaluate if physiological electric fields (EFs)-induced neuronal differentiation is related to the expression patterns of bHLH transcription factors Hes1, Ascl1, and Oligo2, mouse embryonic brain NSCs were used to investigate the expression changes of Ascl1, Hes1 and Oligo2 in mRNA and protein levels during EF-induced neuronal differentiation.

RESULTS

Our results showed that NSCs expressed high level of Hes1, while expression of Ascl1 and Oligo2 stayed at very low levels. When NSCs exited proliferation, the expression of Hes1 in differentiated cells began to decrease and oscillated at the low expression level. Oligo2 showed irregular changes in low expression level. EF-stimulation significantly increased the expression of Ascl1 at mRNA and protein levels accompanied by an increased percentage of neuronal differentiation. What's more, over-expression of Hes1 inhibited the neuronal differentiation induced by EFs.

CONCLUSION

EF-stimulation directed neuronal differentiation of NSCs by promoting the continuous accumulation of Ascl1 expression and decreasing the expression of Hes1.

Genomic and clinicopathological features of lung adenocarcinomas with micropapillary component

BACKGROUND

Lung adenocarcinoma (LA) with a micropapillary component (LAMPC) is a histological subtype of lung cancer that has received increasing attention due to its correlation with poor prognosis, and its tendency to recur and metastasize. At present, comprehensive genomic profiles and clinicopathological features for LAMPC remain unclear and require further investigation.

METHODS

From September 2009 to October 2020, a total of 465 LAMPC patients were recruited and divided into four groups according to MPC proportions, and the correlations between varying proportions of MPCs and clinicopathological characteristics were analyzed. Twenty-nine (29) LAMPC patients and 89 LA patients without MPC (non-MPC) that had undergone NGS testing were selected for further study The comprehensively analyze genomic variations and the difference between LAMPC and MPC were determined. In addition, Gene alterations of LAMPC between Chinese and Western populations were also compared using cBioPortal data.

RESULTS

A higher proportion of MPCs, associated with higher tumor stage, pleural invasion, and vascular tumor thrombus formation, was determined in LA patients. Compared to non-MPC patients, LAMPC patients were determined to have a lower frequency of single nucleotide variants and a higher frequency of insertion-deletion mutations. Mutations in TP53, CTNNB1, and SMAD4, and ALK rearrangements/fusions were significantly more frequent in LAMPC patients. ERBB2 mutations were only detected in non-MPC patients. Gene mutations in the Wnt pathway were significantly more common in LAMPC patients as compared to non-MPC patients. ALK fusions were more prevalent in younger patients. Patients with KRAS or LBP1B mutations had significantly larger tumor diameters than patients with wild-type KRAS or LBP1B. Patients with KRAS mutations were more likely to develop vascular tumor thrombus. Using the cBioPortal public database, we determined that mutations in EGFR were significantly higher in Chinese patients than in a Memorial Sloan Kettering Cancer Center (MSKCC) Western cohort. ALK fusions were exclusively detected in the Chinese cohort, while mutations in KEAP1 and NOTCH4 were only detected in the MSKCC cohort. Our analysis of signaling pathways revealed that Wnt pathway gene mutations were significantly higher in the Chinese cohort.

CONCLUSION

LA patients with higher proportions of MPCs were determined to have a higher tumor stage, pleural invasion, and vascular tumor thrombosis formation. We comprehensively analyzed the genomic mutation characteristics of LAMPC patients and identified multiple, novel MPC-related gene alterations and pathway changes. Our data provide further understanding of the nature of the LAMPC and potential drug-targeted gene alterations, which may lead to new therapeutic strategies.

Comprehensive analyses unveil novel genomic and immunological characteristics of micropapillary pattern in lung adenocarcinoma

Lung adenocarcinoma (LUAD) usually contains heterogeneous histological subtypes, among which the micropapillary (MIP) subtype was associated with poor prognosis while the lepidic (LEP) subtype possessed the most favorable outcome. However, the genomic features of the MIP subtype responsible for its malignant behaviors are substantially unknown. In this study, eight FFPE samples from LUAD patients were micro-dissected to isolate MIP and LEP components, then sequenced by whole-exome sequencing. More comprehensive analyses involving our samples and public validation cohorts on the two subtypes were performed to better decipher the key biological and evolutionary mechanisms. As expected, the LEP and MIP subtypes exhibited the largest disease-free survival (DFS) differences in our patients. EGFR was found with the highest mutation frequency. Additionally, shared mutations were observed between paired LEP and MIP components from single patients, and recurrent mutations were verified in the Lung-Broad, Lung-OncoSG, and TCGA-LUAD cohorts. Distinct biological processes or pathways were involved in the evolution of the two components. Besides, analyses of copy number variation (CNV) and intratumor heterogeneity (ITH) further discovered the possible immunosurveillance escape, the discrepancy between mutation and CNV level, ITH, and the pervasive DNA damage response and WNT pathway gene alternations in the MIP component. Phylogenetic analysis of five pairs of LEP and MIP components further confirmed the presence of ancestral EGFR mutations. Through comprehensive analyses combining our samples and public cohorts, PTP4A3, NAPRT, and RECQL4 were identified to be co-amplified. Multi-omics data also demonstrated the immunosuppression prevalence in the MIP component. Our results uncovered the evolutionary pattern of the concomitant LEP and MIP components from the same patient that they were derived from the same initiation cells and the pathway-specific mutations acquired after EGFR clonal mutation could shape the subtype-specificity. We also confirmed the immunosuppression prevalence in the MIP subtype by multi-omics data analyses, which may have resulted in its unfavorable prognosis.

SOX30 Overexpression Reflects Tumor Invasive Degree, Lymph Node Metastasis and Predicts Better Survival in Colorectal Cancer Patients: A Long-Term Follow-Up Cohort Study

Aims

Sex-determining region Y-box containing gene 30 (SOX30) takes part in the progression of several cancers, while its clinical engagement in colorectal cancer (CRC) is obscure. Therefore, this study aimed to explore the association of SOX30 with clinicopathological features and prognosis in CRC patients.

Methods

Tumor and adjacent noncancerous specimens of 195 CRC patients who received resection were acquired. Furthermore, an immunohistochemistry assay was performed to detect SOX30 protein expression in these specimens; meanwhile, SOX30 mRNA expression was determined by reverse transcription-quantitative polymerase chain reaction assay in 95 out of 195 specimens. Moreover, clinical characteristics and survival data (follow-up duration median (range): 71.0 (7.0-95.0) months) of CRC patients were gathered.

Results

SOX30 protein and mRNA expressions were both decreased in CRC tumor tissue compared to adjacent tissue (both P < 0.001). Furthermore, a negative correlation was found in tumor SOX30 protein expression with tumor size (P = 0.049), lymph node (LYN) metastasis (P = 0.018), T stage (P = 0.001), N stage (P = 0.034), and TNM stage (P = 0.001); tumor SOX30 mRNA expression was also negatively correlated with LYN metastasis (P = 0.001), T stage (P = 0.019), N stage (P = 0.004), and TNM stage (P < 0.001). Furthermore, tumor SOX30 protein expression was positively correlated with overall survival (OS) (P = 0.017), while tumor SOX30 mRNA expression was not correlated with OS (P = 0.070). Multivariate Cox’s regression analysis illustrated that tumor SOX30 protein high expression was an independent factor for favorable OS (hazard ratio: 0.525, P = 0.034).

Conclusions

SOX30 has potential as a biomarker for the progression and prognostication of CRC, which might improve the management of CRC.

The nonsmokers' and smokers' pathways in lung adenocarcinoma: Histological progression and molecular bases

There could be two carcinogenetic pathways for lung adenocarcinoma (LADC): the nonsmokers' pathway and the smokers' pathway. This review article describes the two pathways with special reference to potential relationships between histological subtypes, malignant grades, and driver mutations. The lung is composed of two different tissue units, the terminal respiratory unit (TRU) and the central airway compartment (CAC). In the nonsmokers' pathway, LADCs develop from the TRU, and their histological appearances change from lepidic to micropapillary during the progression process. In the smokers' pathway, LADCs develop from either the TRU or the CAC, and their histological appearances vary among cases in the middle of the progression process, but they are likely converged to acinar/solid at the end. On a molecular genetic level, the nonsmokers' pathway is mostly driven by EGFR mutations, whereas in the smokers' pathway, approximately one-quarter of LADCs have KRAS mutations, but the other three-quarters have no known driver mutations. p53 mutations are an important factor triggering the progression of both pathways, with unique molecular alterations associated with each, such as MUC21 expression and chromosome 12p13-21 amplification in the nonsmokers' pathway, and HNF4α expression and TTF1 mutations in the smokers' pathway. However, investigation into the relationship between histological progression and genetic alterations is in its infancy. Tight cooperation between traditional histopathological examinations and recent molecular genetics can provide valuable insight to better understand the nature of LADCs.