Fanconi anaemia (FA) is an autosomal recessive inherited disorder caused by defects in hematopoietic stem cells. The clinical manifestations of FA are diverse and complicated. FA cells display high hypersensitivity to agents which produce interstrand DNA cross-links such as mitomycin C (MMC) or diepoxybutane (DEB). At least eight complementation groups with defects in eight genes (FANCA, FANCB, FANCC, FANCD(1), FANCD(2), FANCE, FANCF and FANCG) have been identified by gene analysis. Six genes (corresponding to subtypes A, C, D(2), E, F and G) have been coloned, and the encoded FA proteins interact in a common cellular pathway - "FA Pathway", through which modulate DNA repair. The progress of research on FA molecular mechanism provides gene therapy of FA with theory basis. FA cells transduced with the use of retrovirus carring the normal FA gene cDNA manifestate phenotypic correction of hypersensitivity to DNA cross-linking agents, such as MMC. In this review the clinical manifestations and gene composition of FA, and the functions of encoded FA proteins were summarized. The hematopoietic stem cell transplantation and gene therapy for FA patients were discussed.
Cell Cycle Proteins ; DNA-Binding Proteins ; Fanconi Anemia ; genetics ; metabolism ; therapy ; Fanconi Anemia Complementation Group C Protein ; Fanconi Anemia Complementation Group D2 Protein ; Fanconi Anemia Complementation Group Proteins ; Genetic Therapy ; Hematopoietic Stem Cell Transplantation ; Humans ; Mutation ; Nuclear Proteins ; genetics ; Proteins ; analysis ; genetics

OBJECTIVETo investigate the possible relationship between defects in the FA/BRCA pathway of genomic stability and potential pathogenesis of T and B cell lymphoma.

METHODSNineteen cell lines derived from diverse subtypes of lymphoma for possible FA pathway defects were screened.

RESULTSNo defect in FANCD2 ubiquitination was observed. However, the FANCN protein was absent in cell lines HT and Sudhl4. This absence was correlated with enhanced MMC-induced G2 arrest, growth inhibition and high chromosomal breakage rate in both cell lines. In addition, in exon-5a of FANCN gene, a mutation of c.1769 C>T, p. A590V was found in cell line HT, but not in cell line Sudhl4.

CONCLUSIONThis mutation may be the reason causing the absence of the FANCN protein expression or making the protein unstable and losing its function.

Animals ; Antibiotics, Antineoplastic ; pharmacology ; BRCA2 Protein ; metabolism ; Base Sequence ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Chromosome Breakage ; drug effects ; Fanconi Anemia ; metabolism ; Fanconi Anemia Complementation Group D2 Protein ; metabolism ; Fanconi Anemia Complementation Group N Protein ; Gene Expression Regulation, Neoplastic ; Genomic Instability ; Humans ; Lymphoma ; genetics ; pathology ; Mitomycin ; pharmacology ; Molecular Sequence Data ; Mutation ; Nuclear Proteins ; chemistry ; deficiency ; genetics ; metabolism ; Protein Stability ; Sequence Analysis, DNA ; Signal Transduction ; Tumor Suppressor Proteins ; chemistry ; deficiency ; genetics ; metabolism

Fanconi anemia (FA) is an autosomal or X-linked recessive disorder characterized by chromosomal instability, bone marrow failure, cancer susceptibility, and a profound sensitivity to agents that produce DNA interstrand cross-link (ICL). To date, 15 genes have been identified that, when mutated, result in FA or an FA-like syndrome. It is believed that cellular resistance to DNA interstrand cross-linking agents requires all 15 FA or FA-like proteins. Here, we review our current understanding of how these FA proteins participate in ICL repair and discuss the molecular mechanisms that regulate the FA pathway to maintain genome stability.
DNA Damage ; DNA Repair ; Exodeoxyribonucleases ; genetics ; metabolism ; Fanconi Anemia ; genetics ; metabolism ; pathology ; Fanconi Anemia Complementation Group N Protein ; Fanconi Anemia Complementation Group Proteins ; genetics ; metabolism ; Humans ; Nuclear Proteins ; genetics ; metabolism ; Recombinases ; genetics ; metabolism ; Tumor Suppressor Proteins ; genetics ; metabolism ; Ubiquitination

PURPOSE: Fanconi anemia complementation group F (FANCF) is a key factor to maintaining the function of Fanconi anaemia/BRCA (FA/BRCA) pathway, a DNA-damage response pathway. However, the functional role of FANCF in breast cancer has not been elucidated. In the present study, we evaluated the chemosensitization effect of FANCF in breast cancer cells. METHODS: We performed specific knockdown of the endogenous FANCF in breast cancer cells by transfecting the cells with an FANCF short hairpin RNA (shRNA) vector. Cell viability was measured with a Cell Counting Kit-8, and DNA damage was assessed with the alkaline comet assay. The apoptosis, cell cycle, and drug accumulation were measured by flow cytometric analysis. Protein expression levels were determined by Western blot analysis, using specific antibodies. RESULTS: The analyses of two breast cancer cell lines (MCF-7 and MDA-MB-435S) demonstrated that the FANCF shRNA could effectively block the FA/BRCA pathway through the inhibition of Fanconi anemia complementation group D2 ubiquitination. Moreover, FANCF silencing potentiated the sensitivity of cells to mitomycin C (MMC), where combined FANCF shRNA/MMC treatment inhibited cell proliferation, induced S-phase arrest, apoptosis, and DNA fragmentation, and reduced the mitochondrial membrane potential, compared with MMC treatment alone. CONCLUSION: Taken together, this study demonstrates that the inhibition of FANCF by its shRNA leads to a synergistic enhancement of MMC cytotoxicity in breast cancer cells. These results suggest that the inhibition of the FA/BRCA pathway is a useful adjunct to cytotoxic chemotherapy for the treatment of breast cancer.
Apoptosis ; Blotting, Western ; Breast ; Breast Neoplasms ; Cell Count ; Cell Cycle ; Cell Line ; Cell Line, Tumor ; Cell Proliferation ; Cell Survival ; Comet Assay ; Complement System Proteins ; DNA Damage ; DNA Fragmentation ; Fanconi Anemia ; Fanconi Anemia Complementation Group F Protein ; Membrane Potential, Mitochondrial ; Mitomycin ; RNA, Small Interfering ; Ubiquitin ; Ubiquitination

Fanconi anemia (FA) is a rare genetic disorder affecting multiple body systems. Genetic testing, including prenatal testing, is a prerequisite for the diagnosis of many clinical conditions. However, genetic testing is complicated for FA because there are often many genes that are associated with its development, and large deletions, duplications, or sequence variations are frequently found in some of these genes. This study describes successful genetic testing for molecular diagnosis, and subsequent prenatal diagnosis, of FA in a patient and his family in Korea. We analyzed all exons and flanking regions of the FANCA, FANCC, and FANCG genes for mutation identification and subsequent prenatal diagnosis. Multiplex ligation-dependent probe amplification analysis was performed to detect large deletions or duplications in the FANCA gene. Molecular analysis revealed two mutations in the FANCA gene: a frameshift mutation c.2546delC and a novel splice-site mutation c.3627-1G>A. The FANCA mutations were separately inherited from each parent, c.2546delC was derived from the father, whereas c.3627-1G>A originated from the mother. The amniotic fluid cells were c.3627-1G>A heterozygotes, suggesting that the fetus was unaffected. This is the first report of genetic testing that was successfully applied to molecular diagnosis of a patient and subsequent prenatal diagnosis of FA in a family in Korea.
Base Sequence ; Child, Preschool ; Exons ; Fanconi Anemia/*diagnosis/genetics ; Fanconi Anemia Complementation Group A Protein/genetics ; Fanconi Anemia Complementation Group C Protein/genetics ; Fanconi Anemia Complementation Group G Protein/genetics ; Female ; Frameshift Mutation ; Genetic Testing ; Heterozygote ; Humans ; Karyotyping ; Male ; Pregnancy ; Prenatal Diagnosis ; RNA Splice Sites ; Reverse Transcriptase Polymerase Chain Reaction ; Sequence Analysis, DNA

OBJECTIVE: To explore the genetic basis for a fetus with limb abnormality and cardiac malformation. METHODS: Clinical data of a fetus diagnosed at the Shandong Provincial Maternal and Child Health Care Hospital on April 30th, 2021 was collected. Whole exome sequencing (WES) was carried out, and candidate variant was verified by Sanger sequencing and bioinformatic analysis. X-inactivation analysis was carried out for the female members of its family. RESULTS: The fetus was found to have meningoencephalocele, absence of bilateral radii, cleft lip, abnormal great arteries, and single umbilical artery at the gestational age of 11+ weeks. Sequencing revealed that the fetus has harbored a hemizygous c.1162del (p.Y388Tfs*7) variant of the FANCB gene, which was maternally inherited. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG) and ClinGen, the variant was classified as pathogenic (PVS1+PM2_Supporting+PP4). X-inactivation analysis has revealed complete skewed X-inactivation in the pregnant woman and her mother. CONCLUSION The hemizygous c.1162del (p.Y388Tfs*7) variant of the FANCB gene probably underlay the multiple malformations in this fetus.
Female ; Humans ; Pregnancy ; Abnormalities, Multiple ; Cleft Lip ; Fanconi Anemia Complementation Group Proteins ; Fetus ; Gestational Age ; Mothers

BACKGROUND: Lung cancer is the main cause of cancer-related death globally. Single nucleotide polymorphism (SNP) is one of the important factors leading to the occurrence of lung cancer, but its mechanism has not been elucidated. This study intends to investigate the relationship between SNPs of CDH1, FANCB, APC genes and lung cancer genetic susceptibility. METHODS: The case-control study design was used. We collected blood samples from 270 lung cancer cases in the Department of Lung Cancer Surgery, Tianjin Medical University General Hospital, as well as blood samples from 445 healthy volunteers as controls, and extracted genomic DNA for genotyping using the Taqman® SNP genotyping kit. The distribution of three SNP loci of CDH1 gene rs201141645, FANCB gene rs754552650 and APC gene rs149353082 in Chinese population was analyzed. Chi-square test and Logistic regression were used to analyze the relationship between different genotypes and the risk of lung cancer. RESULTS: The distribution frequencies of AA, A/G and GG genotypes at rs754552650 of FANCB gene in the control group were 27.2%, 52.6% and 20.2%, respectively. The distribution frequencies of AA and A/G genotypes were 93.7% and 6.3% in the case group, respectively, and no GG genotype was detected. The A/G genotype of the rs754552650 locus of the FANCB gene was significantly different between the case group and the control group. Compared with the carriers of AA genotype, the individuals with FANCB rs754552650 A/G genotype had a lower risk of lung cancer (OR=0.035, 95%CI: 0.020-0.062, P<0.001). CDH1 gene rs201141645 A/C and CC genotypes only existed in the control group. In addition, only 1 sample was found to have APC rs149353082 genotype in the case group. CONCLUSIONS In the Chinese population, the lung cancer risk of the individuals with FANCB rs754552650 A/G genotype was significantly decreased.
Antigens, CD/genetics* ; Cadherins/genetics* ; Case-Control Studies ; China ; Fanconi Anemia Complementation Group Proteins/genetics* ; Gene Frequency ; Genes, APC ; Genetic Predisposition to Disease ; Genotype ; Humans ; Lung Neoplasms/genetics* ; Polymorphism, Single Nucleotide

Adult ; Asthma ; metabolism ; physiopathology ; Basic-Leucine Zipper Transcription Factors ; genetics ; physiology ; Fanconi Anemia Complementation Group Proteins ; genetics ; physiology ; Female ; Glutamate-Cysteine Ligase ; metabolism ; Humans ; Inflammation ; metabolism ; pathology ; Male ; NF-E2-Related Factor 2 ; genetics ; physiology ; RNA, Messenger ; genetics ; metabolism ; Sputum ; cytology

This study was purposed to investigate the relationship between expression of the FANCG gene and adult sporadic acute myeloid leukemia (AML), real-time PCR with SYBR Green I technique was used for detecting FANCG gene expression level in bone marrow mononuclear cells of 54 newly diagnosed AML patients, 46 AML patients in complete remission (CR) and 36 control samples. β-actin gene was used as internal reference. Relative changes of FANCG gene expression level were detected by 2(-ΔΔCT) method in newly diagnosed AML patients and control samples, in newly diagnosed AML and patient in CR, as well as in AML patients in CR and control samples. The results showed that the relative expression level of FANCG mRNA was 0.56 ± 0.27 in newly diagnosed group, 0.75 ± 0.54 in AML CR group, and 0.85 ± 0.45 in control group. The expression level of FANCG mRNA in newly diagnosed group was significantly lower than that in control and AML CR groups (P < 0.05). There was no statistically significant deference in comparison of AML CR group with the control group (P > 0.05). It is concluded that the expression of FANCG gene decrease in the newly diagnosed AML patients. There is no significant difference between AML CR group and control group, which indicated that FANCG gene may be related with the onset and the prognosis of AML, and may provide a clinical value for evaluating effect of chemotherapy.
Adult ; Fanconi Anemia Complementation Group G Protein ; genetics ; Female ; Humans ; Leukemia, Myeloid, Acute ; genetics ; pathology ; Male ; Middle Aged ; Prognosis ; RNA, Messenger ; genetics ; Real-Time Polymerase Chain Reaction

OBJECTIVETo investigate the effect of PARP1 inhibitor PJ34 on multi-drug resistance in a human multiple myeloma cell line and its connection with FA/BRCA pathway in DNA damage repair.

METHODSA CCK8 assay was used to measure the inhibition rate. Real-time quantitative PCR was used to detect expression changes of DNA repair genes involved in the FA/BRCA pathway. Western blotting assay was used to detect expression of key protein FANCD2 in the FA/BRCA pathway. Annexin VFITC/PI double staining flow cytometry was used to measure cell apoptosis induced by PJ34. A COMET assay was used to detect the effect of PJ34 on DNA damage repair.

RESULTSPJ34 could significantly enhance the sensitivity of RPMI8226/R cells to melphalan. The IC50 value of melphalan was dropped from 20.43 mol/L to 7.8 mol/L. PJ34 could inhibit the DNA damage repair, and the effect was related with the inhibition of FA/BRCA pathway. PJ34 and melphalan showed a synergistic effect in promoting the apoptosis of RPMI8226/R cells.

CONCLUSIONPJ34 can reverse the resistance of RPMI8226/R cells to melphalan by inhibiting the FA/BRCA pathway, which in turn can induce suppression of DNA damage repair. Therefore, PJ34 may have clinical value in overcoming the multi-drug resistance of multiple myeloma.

Antineoplastic Agents ; pharmacology ; BRCA2 Protein ; genetics ; metabolism ; Cell Line, Tumor ; Drug Resistance, Neoplasm ; Fanconi Anemia Complementation Group D2 Protein ; genetics ; metabolism ; Humans ; Multiple Myeloma ; drug therapy ; enzymology ; genetics ; metabolism ; Phenanthrenes ; pharmacology ; Poly (ADP-Ribose) Polymerase-1 ; Poly(ADP-ribose) Polymerase Inhibitors ; Poly(ADP-ribose) Polymerases ; genetics ; metabolism