• Title/Summary/Keyword: Novel mutation

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Checkpoint-inhibition in ovarian cancer: rising star or just a dream?

  • Pietzner, Klaus;Nasser, Sara;Alavi, Sara;Darb-Esfahani, Silvia;Passler, Mona;Muallem, Mustafa Zelal;Sehouli, Jalid
    • Journal of Gynecologic Oncology
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    • 제29권6호
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    • pp.93.1-93.11
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    • 2018
  • The introduction of checkpoint inhibitors revolutionized immuno-oncology. The efficacy of traditional immunotherapeutics, like vaccines and immunostimulants was very limited due to persistent immune-escape strategies of cancer cells. Checkpoint inhibitors target these escape mechanisms and re-direct the immune system to anti-tumor toxicity. Phenomenal results have been reported in entities like melanoma, where no other therapy was able to demonstrate survival benefit, before the introduction of immunotherapeutics. The first experience in ovarian cancer (OC) was reported for nivolumab, a fully human anti-programmed cell death protein 1 (PD1) antibody, in 2015. While the data are extraordinary for a mono-immunotherapeutic agent and very promising, they do not match up to the revolutionary results in entities like melanoma. The key to exceptional treatment response in OC, could be the identification of the most immunogenic patients. We hypothyse that BRCA mutation could be a predictor of improved response in OC. The underlying DNA-repair-deficiancy should result in increased immunogenicity because of higher mutational load and more neoantigen presentation. This hypothesis was not tested to date and should be subject to future trials. The present article gives an overview of the immunologic background of checkpoint inhibition (CI). It presents current data on nivolumab and other checkpoint-inhibitors in solid tumors and OC specifically and depicts important topics in the management of this novel substance group, such as side effect control, diagnostic PD-1/programmed cell death-ligand 1 (PD-L1) expression assessment and management of pseudoprogression.

SCO6992, a Protein with β-Glucuronidase Activity, Complements a Mutation at the absR Locus and Promotes Antibiotic Biosynthesis in Streptomyces coelicolor

  • Jin, Xue-Mei;Choi, Mu-Yong;Tsevelkhoroloo, Maral;Park, Uhnmee;Suh, Joo-Won;Hong, Soon-Kwang
    • Journal of Microbiology and Biotechnology
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    • 제31권11호
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    • pp.1591-1600
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    • 2021
  • Streptomyces coelicolor is a filamentous soil bacterium producing several kinds of antibiotics. S. coelicolor abs8752 is an abs (antibiotic synthesis deficient)-type mutation at the absR locus; it is characterized by an incapacity to produce any of the four antibiotics synthesized by its parental strain J1501. A chromosomal DNA fragment from S. coelicolor J1501, capable of complementing the abs- phenotype of the abs8752 mutant, was cloned and analyzed. DNA sequencing revealed that two complete ORFs (SCO6992 and SCO6993) were present in opposite directions in the clone. Introduction of SCO6992 in the mutant strain resulted in a remarkable increase in the production of two pigmented antibiotics, actinorhodin and undecylprodigiosin, in S. coelicolor J1501 and abs8752. However, introduction of SCO6993 did not show any significant difference compared to the control, suggesting that SCO6992 is primarily involved in stimulating the biosynthesis of antibiotics in S. coelicolor. In silico analysis of SCO6992 (359 aa, 39.5 kDa) revealed that sequences homologous to SCO6992 were all annotated as hypothetical proteins. Although a metalloprotease domain with a conserved metal-binding motif was found in SCO6992, the recombinant rSCO6992 did not show any protease activity. Instead, it showed very strong β-glucuronidase activity in an API ZYM assay and toward two artificial substrates, p-nitrophenyl-β-D-glucuronide and AS-BI-β-D-glucuronide. The binding between rSCO6992 and Zn2+ was confirmed by circular dichroism spectroscopy. We report for the first time that SCO6992 is a novel protein with β-glucuronidase activity, that has a distinct primary structure and physiological role from those of previously reported β-glucuronidases.

Insights into factors affecting synonymous codon usage in apple mosaic virus and its host adaptability

  • Pourrahim, R.;Farzadfar, Sh.
    • Journal of Plant Biotechnology
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    • 제49권1호
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    • pp.46-60
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    • 2022
  • The genetic variability and population structure of apple mosaic virus (ApMV) have been studied; however, synonymous codon usage patterns influencing the survival rates and fitness of ApMV have not been reported. Based on phylogenetic analyses of 52 ApMV coat protein (CP) sequences obtained from apple, pear, and hazelnut, ApMV isolates were clustered into two groups. High molecular diversity in GII may indicate their recent expansion. A constant and conserved genomic composition of the CP sequences was inferred from the low codon usage bias. Nucleotide composition and relative synonymous codon usage (RSCU) analysis indicated that the ApMV CP gene is AU-rich, but G- and U-ending codons are favored while coding amino acids. This unequal use of nucleotides together with parity rule 2 and the effective number of codon (ENC) plots indicate that mutation pressure together with natural selection drives codon usage patterns in the CP gene. However, in this combination, selection pressure plays a more crucial role. Based on principal component analysis plots, ApMV seems to have originated from apple trees in Europe. However, according to the relative codon deoptimization index and codon adaptation index (CAI) analyses, ApMV exhibited the greatest fitness to hazelnut. As inferred from the results of the similarity index analysis, hazelnut has a major role in shaping ApMV RSCU patterns, which is consistent with the CAI analysis results. This study contributes to the understanding of plant virus evolution, reveals novel information about ApMV evolutionary fitness, and helps find better ApMV management strategies.

Inhibition of Tumoral VISTA to Overcome TKI Resistance via Downregulation of the AKT/mTOR and JAK2/STAT5 Pathways in Chronic Myeloid Leukemia

  • Kexin Ai;Mu Chen;Zhao Liang;Xiangyang Ding;Yang Gao;Honghao Zhang;Suwan Wu;Yanjie He;Yuhua Li
    • Biomolecules & Therapeutics
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    • 제32권5호
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    • pp.582-600
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    • 2024
  • Tyrosine kinase inhibitors (TKIs) have revolutionized the treatment landscape for chronic myeloid leukemia (CML). However, TKI resistance poses a significant challenge, leading to treatment failure and disease progression. Resistance mechanisms include both BCR::ABL1-dependent and BCR::ABL1-independent pathways. The mechanisms underlying BCR::ABL1 independence remain incompletely understood, with CML cells potentially activating alternative signaling pathways, including the AKT/mTOR and JAK2/STAT5 pathways, to compensate for the loss of BCR::ABL1 kinase activity. This study explored tumoral VISTA (encoded by VSIR) as a contributing factor to TKI resistance in CML patients and identified elevated tumoral VISTA levels as a marker of resistance and poor survival. Through in vitro and in vivo analyses, we demonstrated that VSIR knockdown and the application of NSC-622608, a novel VISTA inhibitor, significantly impeded CML cell proliferation and induced apoptosis by attenuating the AKT/mTOR and JAK2/STAT5 pathways, which are crucial for CML cell survival independent of BCR::ABL1 kinase activity. Moreover, VSIR overexpression promoted TKI resistance in CML cells. Importantly, the synergistic effect of NSC-622608 with TKIs offers a potent therapeutic avenue against both imatinib-sensitive and imatinib-resistant CML cells, including those harboring the challenging T315I mutation. Our findings highlight the role of tumoral VISTA in mediating TKI resistance in CML, suggesting that inhibition of VISTA, particularly in combination with TKIs, is an innovative approach to enhancing treatment outcomes in CML patients, irrespective of BCR::ABL1 mutation status. This study not only identified a new pathway contributing to TKI resistance but also revealed the possibility of targeting tumoral VISTA as a means of overcoming this significant clinical challenge.

한국의 젊은 여성유방암 환자에서 BRCA 배선유전자 돌연변이는 예후인자인가? (Is the BRCA Germline Mutation a Prognostic Factor in Korean Patients with Early-onset Breast Carcinomas?)

  • 최두호;이민혁
    • Radiation Oncology Journal
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    • 제21권2호
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    • pp.149-157
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    • 2003
  • 목적: 한국인 젊은 여성 유방암 환자에서 유방암 유전자 (BRCA)가 예후인자가 될 수 있는지 알아보기 위하여 본 연구를 시행하였다. 대상 및 방법: 대학병원에서 치료를 받은 환자 중에서 유방암이나 난소암의 가족력과 관계없이 40세 이하의 환자를 선택하였다. 환자의 나이는 18~40세이었고 중앙값은 34.5세이었다. 환자의 말초혈액에서 림프구를 모아 DNA를 추출하였으며 BRCA1과 BRCA2의 모든 염기 중에서 기능과 관계 있는 부위의 DNA를 직접염기서열 결정방식으로 검사하였다. 조직표본 검사가 가능한 환자는 면역화학조직검사를 시행하였다. 대상 및 방법: 60명의 환자 중에서 유방암 발생과 직접 관계가 있는 돌연변이가 11개(18.3%) 있었고(BRCA1 6명, BRCA2 5명), 의미를 알기가 곤란한 돌연변이가 7개 있었으며 반 수 이상의 돌연변이는 이제까지 보고되지 않은 것이었다. 그리고 대부분의 돌연변이 환자는 유방암이나 난소암의 가족력이 관찰되지 않았다. 유방암 유전자 돌연변이 환자는 한 명도 치료의 실패가 없었으며 한 면에서 반대측 유방암이 발생하였다. 7년 무병 생존율은 돌연변이 환자에서 50%, 돌연변이와 관계가 없는 환자에서 79%이었고 차이는 없었다. BRCA 관련 종양에서 에스트로젠, 프로제스테론 수용체 음성의 비율이 높았으며 조직학적 분화도가 낮았으나 예후는 비교대상에 비해 나쁘지 않았다. 결론: 한국의 젊은 여성 유방암 환자는 예후가 인자가 있어도 재발률이 낮았으며 유전자 돌연변이 이환율이 높았으나 암의 발현율은 상대적으로 낮은 것으로 추정되었다 이 결과를 확인하기 위해 더 많은 환자 집단과 오랜 추적기간의 연구가 필요하다.

GNPTAB 유전자에서 새로운 돌연변이가 확인된 뮤코지방증 III형 남매 (A Case Report of Novel Mutation in GNPTAB in Two Siblings with Mucolipidosis Type III Alpha/beta)

  • 김민선;박에스더;송아리;임민지;박형두;조성윤;진동규
    • 대한유전성대사질환학회지
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    • 제18권3호
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    • pp.99-106
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    • 2018
  • 뮤코지방증 III alpha/beta는 GNPTAB 유전자의 돌연변이로 야기되는 점액(Mucolipids) 분해 능력 장애이며 상염색체 열성으로 유전된다. 이는 혈액에서 고농축의 점액을 검사하여 진단되며 유전자 검사를 통해 진단을 확인할 수 있다. 뮤코지방증 III형은 희귀하고 점진적으로 진행하는 대사장애로 증상은 3세 경에 나타나며 성장지연, 관절 경직, 관절통, 골격 이상, 심장 판막 이상, 반복되는 호흡기 감염, 평평한 얼굴과 낮은 콧대의 거친 얼굴, 지적장애 또는 학습 문제를 보인다. 본 증례는 성장 지연과 거친 얼굴을 보이는 4세, 2세 7개월 남매에서 targeted gene panel sequencing으로 [c.2715+1G>A (p.Glu906Leufs*4), c.2544del (p. Glu849Lysfs*22)] 두 개의 변이가 이형 접합체로 발견되어 뮤코지방증 III형을 진단하였으며 c.2544del 은 새로운 돌연변이로 대조군에서 발견되지 않았고 표현형과 연관성 고려 시 pathogenic variant로 해석된다. 이와 같이 GNPTAB 유전자에서 새로운 돌연변이가 확인되어 뮤코지방증 III형 남매 증례를 보고하는 바이다. 본 증례처럼 최근 분자유전학적 기술이 발달함에 따라 조기 진단이 가능해지고 진단 후 Case 1 환자에서와 같이 치료를 위하여 pamidronate 투약 가능하나, 이와 같은 보조적 치료 외에도 조기 진단을 받은 뮤코지방증 환자들을 위한 근본적인 치료법 개발을 위한 노력이 필요하다.

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Mutations in Streptomycin Resistance Genes and Their Relationship to Streptomycin Resistance and Lineage of Mycobacterium tuberculosis Thai Isolates

  • Hlaing, Yin Moe;Tongtawe, Pongsri;Tapchaisri, Pramuan;Thanongsaksrikul, Jeeraphong;Thawornwan, Unchana;Archanachan, Buppa;Srimanote, Potjanee
    • Tuberculosis and Respiratory Diseases
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    • 제80권2호
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    • pp.159-168
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    • 2017
  • Background: Streptomycin (SM) is recommended by the World Health Organization (WHO) as a part of standard regimens for retreating multidrug-resistant tuberculosis (MDR-TB) cases. The incidence of MDR-TB in retreatment cases was 19% in Thailand. To date, information on SM resistance (SMR) gene mutations correlated to the SMR of Mycobacterium tuberculosis Thai isolates is limited. In this study, the mutations in rpsL, rrs, gidB, and whiB7 were investigated and their association to SMR and the lineage of M. tuberculosis were explored. Methods: The lineages of 287 M. tuberculosis collected from 2007 to 2011 were identified by spoligotyping. Drug susceptibility profiles were evaluated by the absolute concentration method. Mutations in SMR genes of 46 SM-resistant and 55 SM-susceptible isolates were examined by DNA sequencing. Results: Three rpsL (Lys43Arg, Lys88Arg, and Lys88Thr) and two gidB (Trp45Ter and Gly69Asp) mutations were present exclusively in the SM resistant M. tuberculosis. Lys43Arg rpsL was the most predominant SMR mutations (69.6%) and prevailed among Beijing isolates (p<0.001). No SMR-related mutation in was found rrs. The combination of rpsL and gidB mutations provided 76.1% sensitivity for detecting SMR in M. tuberculosis Thai isolates. whiB7 was not responsible for SMR in SM resistant isolates lacking rpsL and rrs mutations. The significance of the three gidB mutations, 276A>C, 615A>G, and 330G>T, as lineage signatures for Beijing and EAI were underscored. This study identified 423G>A gidB as a novel sub-lineage marker for EAI6-BGD1. Conclusion: Our study suggested that the majority of SMR in M. tuberculosis Thai isolates were responsible by rpsL and gidB polymorphisms constantly providing the novel lineage specific makers.

Association of Novel Polymorphisms in Lymphoid Enhancer Binding Factor 1 (LEF-1) Gene with Number of Teats in Different Breeds of Pig

  • Xu, Ru-Xiang;Wei, Ning;Wang, Yu;Wang, Guo-Qiang;Yang, Gong-She;Pang, Wei-Jun
    • Asian-Australasian Journal of Animal Sciences
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    • 제27권9호
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    • pp.1254-1262
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    • 2014
  • Lymphoid enhancer binding factor 1 (LEF-1) is a member of the T-cell specific factor (TCF) family, which plays a key role in the development of breast endothelial cells. Moreover, LEF-1 gene has been identified as a candidate gene for teat number trait. In the present study, we detected two novel mutations (NC_010450.3:g. 99514A>G, 119846C>T) by DNA sequencing and polymerase chain reaction-restriction fragment length polymorphism in exon 4 and intron 9 of LEF-1 in Guanzhong Black, Hanjiang Black, Bamei and Large White pigs. Furthermore, we analyzed the association between the genetic variations with teat number trait in these breeds. The 99514A>G mutation showed an extremely significant statistical relevance between different genotypes and teat number trait in Guanzhong (p<0.001) and Large White (p = 0.002), and significant relevance in Hanjiang (p = 0.017); the 119846C>T mutation suggested significant association in Guanzhong Black pigs (p = 0.042) and Large White pigs (p = 0.003). The individuals with "AG" or "GG" genotype displayed more teat numbers than those with "AA"; the individuals with "TC" or "CC" genotype showed more teat numbers than those with "TT". Our findings suggested that the 99514A>G and 119846C>T mutations of LEF-1 affected porcine teat number trait and could be used in breeding strategies to accelerate porcine teat number trait improvement of indigenous pigs breeds through molecular marker assisted selection.

An improvement of real-time polymerase chain reaction system based on probe modification is required for accurate detection of African swine fever virus in clinical samples in Vietnam

  • Tran, Ha Thi Thanh;Dang, Anh Kieu;Ly, Duc Viet;Vu, Hao Thi;Hoang, Tuan Van;Nguyen, Chinh Thi;Chu, Nhu Thi;Nguyen, Vinh The;Nguyen, Huyen Thi;Truong, Anh Duc;Pham, Ngoc Thi;Dang, Hoang Vu
    • Asian-Australasian Journal of Animal Sciences
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    • 제33권10호
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    • pp.1683-1690
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    • 2020
  • Objective: The rapid and reliable detection of the African swine fever virus (ASFV) plays an important role in emergency control and preventive measures of ASF. Some methods have been recommended by FAO/OIE to detect ASFV in clinical samples, including realtime polymerase chain reaction (PCR). However, mismatches in primer and probe binding regions may cause a false-negative result. Here, a slight modification in probe sequence has been conducted to improve the qualification of real-time PCR based on World Organization for Animal Health (OIE) protocol for accurate detection of ASFV in field samples in Vietnam. Methods: Seven positive confirmed samples (four samples have no mismatch, and three samples contained one mutation in probe binding sites) were used to establish novel real-time PCR with slightly modified probe (Y = C or T) in comparison with original probe recommended by OIE. Results: Both real-time PCRs using the OIE-recommended probe and novel modified probe can detect ASFV in clinical samples without mismatch in probe binding site. A high correlation of cycle quantification (Cq) values was observed in which Cq values obtained from both probes arranged from 22 to 25, suggesting that modified probe sequence does not impede the qualification of real-time PCR to detect ASFV in clinical samples. However, the samples with one mutation in probe binding sites were ASFV negative with OIE recommended probe but positive with our modified probe (Cq value ranked between 33.12-35.78). Conclusion: We demonstrated for the first time that a mismatch in probe binding regions caused a false negative result by OIE recommended real-time PCR, and a slightly modified probe is required to enhance the sensitivity and obtain an ASF accurate diagnosis in field samples in Vietnam.

새로운 ABCD1 유전자의 돌연변이를 가지는 소아 대뇌형 부신백질이영양증 1례 (A Case of Childhood Cerebral Form Adrenoleukodystrophy with Novel Mutation in the ABCD1 Gene)

  • 신영림
    • 대한유전성대사질환학회지
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    • 제12권1호
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    • pp.49-53
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    • 2012
  • X 연관 부신백질이영양증(adrenoleukodystrophy, ALD)은 과산화소체베타산화과정(peroxisomal ${\beta}$-oxidation)의 장애로 매우긴사슬지방산(very long chain fatty acids, VLCFA)이 신경계의 백질과 부신피질 및 고환에 축척된다. 이 질환은 과산화소체막단백질(peroxisomal membrane protein)을 형성하는 Xq28에 위치하는 ATP-binding cassette, subfamily D, member 1 (ABCD1) 유전자 돌연변이에 의해 주로 발생한다. X 연관 ALD는 다양한 임상양상을 보이는데 전형적인 소아대뇌형 부신백질이영양증은 10세 이전의 남아에서 대뇌백질에 빠르게 진행하는 탈수초현상을 보인다. 8세 된 남자 환아로 정상발달과정을 보이던 중 초등학교 입학 후에 집중장애와 산만한 모습으로 인해 주의력결핍과다활동장애로 진단받고 치료를 받았었다. 환아는 내원 8개월 전부터 말이 어눌해 지고 걸을 때 오른 발을 끌며 자주 넘어지는 모습을 보여 내원하였고 오른쪽 상, 하지의 근력이 떨어지는 양상이 관찰되었다. 검사상 부신기능저하증 소견을 보였으며 혈청 지방산 분석검사에서는 C26:0, C42:0/C22:0, C26:0/C22:0가 증가하였다. 뇌 자기공명영상에서는 T2와 FLAIR 강조영상에서 양측의 두정후두부의 백질과 소뇌의 백질에서 대칭적으로 고신호강도를 보였다. 환아는 부신백질이영양증로 진단하였고 ABCD1 유전자 분석 검사에서 새로운 c.983delT (p.Met329CysfsX7) 돌연변이가 확인되었다. X 연관 ALD는 유전자형과 표현형에 연관성이 없으며 다양한 임상양상을 보이기 때문에 환자들마다 임상증상을 잘 관찰해야 하며 향후 유전자 기능을 좀 더 파악하고 임상증상에 영향을 주는 다른 요소에 대한 연구가 필요할 것이라 사료된다.

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