Novel sequence variants in the LIPH and LPAR6 genes underlies autosomal recessive woolly hair/hypotrichosis in consanguineous families

Identification of LIPH as an unfavorable biomarkers correlated with immune suppression or evasion in pancreatic cancer based on RNA-seq

BACKGROUND

It is widely considered that pancreatic cancer (PC) is an immunosuppressive cancer. Immune-based therapies remain promising therapeutic strategies for PC. Overexpression of lipase H (LIPH) was reported to be related to immunity in cattle and has also been demonstrated to promote tumor progression in several tumors, but its role in pancreatic carcinogenesis remains unclear. Study on LIPH in PC might provide a new insight into the immunosuppression in PC.

METHODS

The potential biological and clinical significance of LIPH was evaluated by bioinformatics analysis. We further investigated potential associations between the expression of LIPH and tumor immune infiltration using the CIBERSORT algorithm, the ESTIMAT algorithm, and single sample gene set enrichment analysis (ssGSEA).

RESULTS

LIPH was significantly overexpressed in tumor tissues compared with normal tissues. LIPH overexpression correlated with tumor recurrence, advanced histologic grade, and poorer overall survival (OS). Four of the most common somatic mutation, including KRAS, TP53, CDKN2A, and SMAD4, in PC were all correlated with high LIPH expression. And high LIPH expression was significantly correlated with KRAS activation and SMAD4 inactivation. Besides, LIPH expression was involved in various biological pathways such as negative regulation of cell-cell adhesion, actin cytoskeleton, EMT, angiogenesis, and signaling by MST1. And LIPH overexpression caused high infiltration of TAMs, Treg cells, and Th2/Th1, but reduced the infiltration of CD8⁺ T cells and Th1 cells.

CONCLUSIONS

Our findings demonstrated that LIPH correlated with immune suppression or evasion and may function as a novel unfavorable prognostic biomarker in PC.

Isolated autosomal recessive woolly hair/hypotrichosis: genetics, pathogenesis and therapies

Isolated autosomal recessive woolly hair/hypotrichosis (ARWH) is a rare hereditary hair disease characterized by tightly curled sparse hair at birth or in early infancy. Patients with ARWH consist of genetically heterogeneous groups. Woolly hair autosomal recessive 1 (ARWH1) (MIM #278150), woolly hair autosomal recessive 2 (ARWH2) (MIM #604379) and woolly hair autosomal recessive 3 (ARWH3) (MIM #616760) are caused by mutations in LPAR6, LIPH and KRT25, respectively. In addition, nonsense variants in C3ORF52 (*611956) were identified in ARWH patients. The frequencies of the mutations in the causative genes in ARWH patients are thought to differ by ethnicity and country/geographical area. Large numbers of ARWH families with LIPH mutations have been described only in populations from Japan, Pakistan and the Volga-Ural region of Russia. In that region of Russia, most ARWH families have an extremely prevalent founder mutation, the deletion of exon 4, in LIPH. In the Pakistani population, 47.2% of ARWH families had the disease due to LIPH mutations and 52.8% of them carried LPAR6 mutations. The prevalent, recurrent LIPH mutation c.659_660delTA (p.Ile220Argfs*29) was found in more than half of Pakistani ARWH families with LIPH mutations. Most Japanese ARWH families (98.7%) harbour LIPH mutations, including the two highly prevalent, recurrent LIPH mutations c.736T>A (p.Cys246Ser) and c.742C>A (p.His248Asn). In ARWH patients whose disease was due to LIPH, LPAR6 or C3ORF52 mutations, the loss of function of LIPH, LPAR6 or C3ORF52 leads to reduced LIPH-LPA-LPAR6 signalling, resulting in the decreased transactivation of EGFR signalling and the phenotype of underdeveloped hairs. Our recent prospective interventional study suggests that topical minoxidil might be a promising treatment for ARWH due to LIPH mutations, although sufficiently effective treatments have not been established for ARWH yet.

Novel small-insertion mutation in the LIPH gene in a patient with autosomal recessive woolly hair/hypotrichosis

Autosomal recessive woolly hair/hypotrichosis (ARWH/H) is a rare form of congenital alopecia, which can be caused by mutations in lipase H (LIPH), lysophosphatidic acid receptor 6 (LPAR6/P2RY5) or keratin 25 (KRT25) genes. We present a 32-year-old woman with typical clinical features of ARWH. Hair microscopy was performed to observe differences between the patient's hair and a normal sample. Next-generation sequencing was used to detect pathogenic mutations. Sanger sequencing was used to further confirm the mutations. Abnormal hair appearance was found by hair microscopy. A novel frame-shift mutation (NM_139248: c.686delinsGTAGAACCCAACCTGGCT: p.Asp229fs37X) and a reported mutation (NM_139248: exon6:c.T736A: p.C246S) in LIPH were identified in the patient. All reported mutations related to ARWH of various races were reviewed. Our study provides further evidence of the similarity of ARWH between the Chinese and Japanese population. A novel small-insertion mutation also expands the LIPH mutation spectrum.

Lipase member H is a downstream molecular target of hypoxia inducible factor-1α and promotes papillary thyroid carcinoma cell migration in BCPAP and KTC-1 cell lines

Background

Papillary thyroid carcinoma (PTC) is the most common type of thyroid carcinoma, which is associated with a high incidence of lymph-node metastasis. Multiple biomarkers have been identified for the precise diagnosis of PTC at an early stage. However, their role in PTC remains poorly elucidated. Previously, we reported that lipase H (LIPH), a membrane-bound protein, was highly expressed in PTC. This study aimed to fully elucidate the causal role of LIPH in the development of PTC and investigated its relationship with lymph-node metastasis in PTC.

Materials and methods

Quantitative reverse transcription PCR and immunohistochemistry were used to measure the mRNA and protein expression levels of LIPH in 45 and 6 pairs of PTC tissues and adjacent normal tissues, respectively. Clinical tissue data of 504 PTC tissues and 60 normal thyroid tissues from The Cancer Genome Atlas database were used to analyze the correlation between LIPH expression level and clinical features in PTC. siRNAs were used to knock down genes, while plasmids were used to overexpress genes. Two PTC cell lines (KTC-1 and BCPAP) were used in subsequent cytological function studies. In addition, a hypoxia stress model was constructed using cobaltous chloride hexahydrate reagent, and the protein expression level of the corresponding biomarkers was measured by Western blotting.

Results

This study revealed that high expression of LIPH in PTC was closely associated with lymph-node metastasis. Our cellular function experiments indicated that LIPH positively correlated with the malignant behavior of PTC cell lines. We further confirmed the role of LIPH in hypoxia and its relationship with the epithelial–mesenchymal transition pathway in PTC.

Conclusion

LIPH plays an important role in PTC oncogenesis and development, especially in lymph-node metastasis. It can be regarded as a biomarker for the diagnosis and treatment of PTC in the near future.