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PubMed1999

The A1555G mutation in the 12S rRNA gene of human mtDNA: recurrent origins and founder events in families affected by sensorineural deafness.

The mtDNA variation of 50 Spanish and 4 Cuban families affected by nonsyndromic sensorineural deafness due to the A1555G mutation in the 12S rRNA gene was studied by high-resolution RFLP analysis and sequencing of the control region. Phylogenetic analyses of haplotypes and detailed survey of population controls revealed that the A1555G mutation can be attributed to >/=30 independent mutational events among the 50 Spanish families and that it occurs on mtDNA haplogroups that are common in all European populations. This indicates that the relatively high detection rate of this mutation in Spain is not due to sampling biases or to a single major founder event. Moreover, the distribution of these mutational events on different haplogroups is compatible with a random occurrence of the A1555G mutation and tends to support the conclusion that mtDNA backgrounds do not play a significant role in the expression of the mutation. Overall, these findings appear to indicate that the rare detection of this mutation in other populations is most likely due to inadequacy in patient ascertainment and molecular screening. This probable lack of identification of the A1555G mutation in subjects affected by sensorineural hearing loss implies that their maternally related relatives are not benefiting from presymptomatic detection and information concerning their increased risk of ototoxicity due to aminoglycoside treatments.

DNA Mutational Analysis↗
PubMed2004

Vulvar intraepithelial neoplasia p53 expression, p53 gene mutation and HPV in recurrent/progressive cases.

OBJECTIVE: To evaluate p53 protein overexpression and p53 gene mutation in primary and recurrent undifferentiated vulvar intraepithelial neoplasia (VIN), establishing the recurrence and progression rates, median time interval, and sites of the initial lesion and first recurrence, addressing the relationship with HPV infection. STUDY DESIGN: Twenty women with undifferentiated VIN treated with wide surgical excision were followed every 6 months for 7 years and divided into groups with and without recurrence/progression. p53 Protein was detected in paraffin sections using the monoclonal p53 antibody. DNA was extracted from paraffin sections. Polymerase chain reaction/single strand conformation polymorphism (PCR-SSCP) analysis was utilized to screen for p53 gene mutations in exons 5-8. HPV was determined by digesting PCR products with restriction endonucleases. RESULTS: Recurrences were observed in 8 (40%) patients and progression to cancer in 1 (5%). Two cases recurred twice. The median interval for recurrence/progression was 24.5 months. Recurrent/progressive lesions were located in the same area of the initial lesions in 10 cases (91%). p53 Overexpression was observed in 50% (10/20) of primary lesions, of which 45% corresponded to the 9 recurrent/progressive cases. p53 Overexpression was detected in 81.8% (9/11) of recurrent/progressive cases. In the last 2 cases PCR-SSCP showed p53 gene mutation. The rate of HPV infection was higher in the group without recurrence. CONCLUSION: p53 Gene mutation plays an important role in undifferentiated VIN pathogenesis independent of high-risk HPV infection and may predict recurrence or progression to vulvar cancer. Undifferentiated VIN recurrent/progressive VIN lesions have a tendency to occur in the same area of the initial lesions, suggesting a molecular disturbance.

Adult↗
PubMed2004

The major allele of the alanine:glyoxylate aminotransferase gene: seven novel mutations causing primary hyperoxaluria type 1.

We describe 7 novel mutations occurring on the major allele of the human AGT gene in patients with primary hyperoxaluria type 1, an autosomal recessive disease resulting from a deficiency of the liver peroxisomal enzyme alanine:glyoxylate aminotransferase (AGT; EC 2.6.1.44). These mutations include 3 small deletions, 570delG, 744delC, and 983_988del, two splice junction mutations, IVS7-1G-->C and IVS8+1G-->T, and two nonsense mutations, R111X and W251X. We have also identified recurrences of previously identified reported mutations, 679-(IVS6+2)delAAgt, IVS8-3C-->G and 33insC. Deletion mutation 679-(IVS6+2)delAAgt has now been identified in a second Chinese patient and may be specific to that population. In contrast, 33insC has been found in patients of varying ethnic and racial backgrounds; a single vs multiple origin for this mutation is thus an intriguing question. It also appears to occur at a high frequency on the major allele. Five of the novel mutations were detected in patients who were compound heterozygotes for one of the common mis-targeting mutation, G170R or F152I, while the other two mutations occurred in the same patient.

Adult↗
PubMed2005

Adaptation of Spirogyra insignis (Chlorophyta) to an extreme natural environment (sulphureous waters) through preselective mutations.

Adaptation of Spirogyra insignis (Chlorophyceae) to growth and survival in an extreme natural environment (sulphureous waters from La Hedionda Spa, S. Spain) was analysed by using an experimental model. Photosynthesis and growth of the alga were inhibited when it was cultured in La Hedionda Spa waters (LHW), but after further incubation for several weeks, the culture survived due to the growth of a variant that was resistant to LHW. A Luria-Delbruck fluctuation analysis was carried out to distinguish between resistant filaments arising from rare spontaneous mutations and resistant filaments arising from other mechanisms of adaptation. It was demonstrated that the resistant filaments arose randomly by rare spontaneous mutations before the addition of LHW (preselective mutations). The rate of spontaneous mutation from sensitivity to resistance was 2.7 x 10(-7) mutants per cell division. Since LHW(resistant) mutants have a diminished growth rate, they are maintained in nonsulphureous natural waters as the result of a balance between new resistants arising from spontaneous mutation and resistants eliminated by natural selection. Thus, recurrence of rare spontaneous preselective mutations ensures the survival of the alga in sulphureous waters.

Adaptation, Physiological↗
PubMed2005

Epidermal growth factor receptor gene mutations and increased copy numbers predict gefitinib sensitivity in patients with recurrent non-small-cell lung cancer.

PURPOSE: To evaluate epidermal growth factor receptor (EGFR) mutations and copy number as predictors of clinical outcome in patients with non-small-cell lung cancer (NSCLC) receiving gefitinib. PATIENTS AND METHODS: Sixty-six patients with NSCLC who experienced relapse after surgery and received gefitinib were included. Direct sequencing of exons 18 to 24 of EGFR and exons 18 to 24 of ERBB2 was performed using DNA extracted from surgical specimens. Pyrosequencing and quantitative real-time polymerase chain reaction were performed to analyze the allelic pattern and copy number of EGFR. RESULTS: Thirty-nine patients (59%) had EGFR mutations; 20 patients had deletional mutations in exon 19, 17 patients had missense mutations (L858R) in exon 21, and two patients had missense mutations (G719S or G719C) in exon 18. No mutations were identified in ERBB2. Response rate (82% [32 of 39 patients] v 11% [three of 27 patients]; P < .0001), time to progression (TTP; median, 12.6 v 1.7 months; P < .0001), and overall survival (median, 20.4 v 6.9 months; P = .0001) were significantly better in patients with EGFR mutations than in patients with wild-type EGFR. Increased EGFR copy numbers (> or = 3/cell) were observed in 29 patients (44%) and were significantly associated with a higher response rate (72% [21 of 29 patients] v 38% [14 of 37 patients]; P = .005) and a longer TTP (median, 9.4 v 2.6 months; P = .038). High EGFR copy numbers (> or = 6/cell) were caused by selective amplification of mutant alleles. CONCLUSION: EGFR mutations and increased copy numbers were significantly associated with better clinical outcome in gefitinib-treated NSCLC patients.

Adult↗
PubMed2004

p53 Gene mutations in superficial bladder cancer.

OBJECTIVES: To assess the presence of p53 gene mutations in superficial tumors of the urinary bladder (transitional cell carcinoma) and their relationship to classic prognostic factors for cancer recurrence and progression. To analyze the implication of these mutations on the P53 protein structure. MATERIALS AND METHODS: Observational, cross-sectional study of 90 consecutive patients, 60 with superficial transitional cell carcinoma (pTa and pT1) and 30 without neoplastic disease (control group). Samples of bladder tumor and control normal mucosa were analyzed by polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) to detect p53 mutations in exons 5-9. Automatic sequencing was used to characterize the mutations and their effect on the P53 protein was analyzed. Bivariate analysis was used to assess the association with other prognostic factors. RESULTS: PCR-SSCP found no mutations in any control group patient, whereas 38.3% of patients with superficial transitional cell carcinoma had one or more mutations in the exons analyzed. Thirty mutations were sequenced; all were point mutations and 86.67% were considered relevant for the P53 structure. A total of 93.3% of the mutations were located in highly conserved regions and 73.3% in mutational hot spots. The highest cell differentiation grades and pT1 stage were associated with a higher incidence of p53 gene mutations. Previous recurrences and other tumor-related histological variables were not associated with a higher percentage of mutations. CONCLUSION: Mutations at p53 did not appear in healthy bladder mucosa and were significantly more frequent in pT1 and high-grade (G-II and G-III) tumors. All mutations detected were point mutations and most caused considerable P53 structural abnormalities, implying major repercussions on P53 function. These data suggest that certain p53 mutations may have prognostic value, even though they were not associated with other classic recurrence and tumor progression parameters. Future analyses of the progress of patients with superficial bladder transitional cell carcinoma and mutated p53 will help clarify this aspect.

Aged↗
PubMed1993

Deoxycytidine methylation and the origin of spontaneous transition mutations in mammalian cells.

Previously we described a recurrent, site-specific G4784 --> A transition mutation affecting exon V of the Chinese hamster ovary cell RPS14 gene. Because the mutation is located within a CpG dinucleotide, we considered the possibility that deoxycytidine methylation might be responsible for the transition's unusually high frequency and site specificity. Therefore, we used a procedure based on the PCR amplification of bisulfite-modified genomic DNA to analyze the pattern of DNA cytosine methylation in exon V of the CHO cell RPS14 locus. Our data indicate that the CpG dinucleotide targeted by the transition mutation is stably methylated in CHO cell chromosomes. This finding supports the notion that deoxycytidine methylation promotes "spontaneous", site-specific transition mutations in mammalian cells.

Amino Acid Sequence↗
PubMed2025

Unusual relapse dynamics in EGFR-mutated lung adenocarcinoma uncovered by genomic profiling: Insights from a case report.

Synchronous or metachronous multiple NSCLCs challenge clinical practice, particularly in distinguishing multiple separate primary lung cancers (SPLC) from intrapulmonary metastasis (IPM) for accurate staging and management. Here, we present a unique case of three resected lung adenocarcinomas (LUAD) from a single patient collected at different time points, all harboring the same EGFR p.L858R somatic driver mutation but exhibiting distinct clonal trajectories. Whole exome sequencing (WES) analysis revealed that the first tumor was an independent primary tumor, while the latter two tumors were clonally related. Our findings highlight the complexity of tumor progression and provide insights into clonal heterogeneity. This report underscores the importance of genomic profiling for discriminating SPLC from IPM and emphasizes that the detection of a single shared driver mutation is not sufficient to prove metastasis.

Humans↗
PubMed1989

Familiarity, recessivity and germline mosaicism.

In man evidence of autosomal recessive disease is usually based on a high sib risk, absence of parent-child transmission and increased consanguinity. Discrimination from what are sometimes termed multifactorial disorders and their associated environmental effects is usually based on the latter having a lower recurrence risk, an increased recurrence risk after a second affected child and no increase in consanguinity. Another cause of familial disorders with recurrence restricted to sibs which has received little attention is germline mosaicism for a mutation expressed as a dominant. If, for example, an embryonic mutation resulted in half the precursors of the germ cells carrying a mutation with dominant expression, then the proportion of haploid nuclei conveying the mutation, which is the recurrence risk, would be a quarter. If severity precluded reproduction the disorder would tend to be classified as a recessive. While germline mosaicism will rarely be expressed with such a high recurrence risk, the estimation of this risk in rare disorders is difficult due to extreme and unpredictable bias in ascertainment.

Consanguinity↗
PubMed1999

Clonal origin of recurrent meningiomas.

Meningiomas are common intracranial and intraspinal tumors. They are treated primarily by surgical resection. Meningioma recurrence following surgery is frequent despite advances in microneurosurgery. However, it is not clear whether recurrent meningiomas, close or distant to the primary resection site, arise from incomplete resection, dissemination of tumor fragments or from independent tumor growth. In order to address the question of clonality in recurring meningiomas, we examined a series of five patients with a total of 14 tumors for X-chromosome inactivation in the tumor tissues. Four patients with a total of 11 meningiomas were informative for polymorphisms either in the PGK or the AR genes. All recurrent meningiomas were found to be clonal with respect to the primary lesions. This finding suggests a common molecular pathogenesis of primary meningioma and subsequent recurrences (p<0.01). In a sixth patient, we analyzed the NF2 gene for mutations in the primary and 5 recurrent meningiomas. All six lesions carried the identical NF2 mutation, strongly indicating a common origin for these tumors. We conclude that recurrent meningiomas usually arise from dissemination of tumor fragments, most likely at the time of the first surgical resection. Our data should alert to the potential of meningioma cells for seeding during surgical procedures.

DNA Mutational Analysis↗
PubMed2002

Arterial wall thickness and the risk of recurrent ischemic events in carriers of the prothrombin G20210A mutation with clinical manifestations of atherosclerosis.

The G20210A mutation in the prothrombin gene is an established risk factor for venous thrombosis. There is controversy about the role of this mutation in arterial thrombotic disease and atherosclerosis. We determined the presence of the prothrombin mutation and examined its influence on carotid and femoral artery intima-media thickness (IMT) and the occurrence of new ischemic events during follow-up in 277 patients with clinically manifest atherosclerotic disease: ischemic stroke, myocardial infarction or peripheral arterial disease. The mean age at entry was 63 years. Mean IMT was significantly higher in carriers of the prothrombin mutation (1.17 (SD 0.29) mm versus 0.97 (SD 0.25) mm: (delta)IMT=0.20, P=0.02). The increase in IMT was not attributable to differences in age, type of arterial disease or cardiovascular risk factors between carriers and non-carriers. During a mean follow-up of 3.5 years, a strong trend for more ischemic events was observed: 4 of the 11 carriers suffered from a recurrent ischemic event, compared with 30 of the 164 male non-carriers (36 versus 18%; P=0.06). These results suggest that the G20210A mutation contributes to the process of arterial wall thickening and is associated with the occurrence of ischemic events in a cohort of elderly persons with established atherosclerosis.

Aged↗
PubMed2000

Molecular staging of colorectal cancer: K-ras mutation analysis of lymph nodes upstages Dukes B patients.

PURPOSE: Multiple attempts have been made to improve the clinical/pathologic staging system of Dukes to focus adjuvant therapy decisions. The purpose of this study was to determine whether K-ras mutational status of regional nodes in patients with Dukes B2 colorectal cancer could be used to stage their disease more accurately. METHODS: Using formalin-fixed, paraffin-embedded archival material, tumor samples were screened for K-ras mutations using a mutation-specific polymerase chain reaction method, followed by gel electrophoresis in a 96-well array. Patients with Dukes B2 tumors that have mutations in codon 12 or 13 of the K-ras gene were identified. RESULTS: Mutational analysis of the lymph nodes from these patients revealed an 80 percent (16/20) incidence of the same mutations in regional lymph nodes. None of the four patients with mutation-free nodes developed recurrence compared with 37.5 percent (6/16) with K-ras positive lymph nodes. CONCLUSIONS: The data suggest that patients with Dukes B2 colorectal cancers that have mutations in codon 12 or 13 of the K-ras gene are at high risk for the development of nodal metastases. Mutational analysis of the lymph nodes identifies high-risk patients who should be considered for adjuvant chemotherapy. Therefore, K-ras mutational analysis should be considered for molecular staging of colorectal cancer.

Adenocarcinoma↗
PubMed2001

Severe factor VII deficiency with recurrent intracranial haemorrhages owing to double heterozygosity for a splice site mutation of an IVS4 and a novel nonsense mutation in exon 8 (Gln211-->Term).

Genetic analysis of a 10-month-old Japanese baby boy with recurrent intrathoracic bleeding, cerebral haemorrhages and gastrointestinal bleeding secondary to severe factor VII (FVII) deficiency revealed evidence of two distinct mutations of FVII: a splice site mutation of G-->A at nucleotide 6071 in the IVS4 splice site and a novel nonsense mutation (Gln211-->Term) in exon 8. His bleeding was difficult to control without prophylactic infusion of FVII. We detected a heterozygous splice site mutation of the IVS4 in his mother and a heterozygous nonsense mutation in exon 8 (Gln211-->Term) in his father. The parents' FVII levels are both 50% of normal controls. The FVII:C in plasma from the proband was < 1.5% of normal controls. FVII:antigen (Ag) was < 1% of normal controls, using a monoclonal antibody (mAb) hVII-B101/1 that specifically reacts with FVII epidermal growth factor 1 (EGF-1), and 5% of normal controls, using a rabbit polyclonal antibody against human FVII. After immunoadsorption with mAb hVII-B101/B1-Sepharose 4B, FVII levels of both the proband and his mother were 5% of normal controls; after immunoadsorption the FVII levels of normal subjects were < 1%. We hypothesize that secretion of a small amount of dysfunctional FVII lacking EGF-1 into the circulation accounts for this observation.

Codon, Nonsense↗
PubMed2001

The spectrum of pathogenic mutations in SPINK5 in 19 families with Netherton syndrome: implications for mutation detection and first case of prenatal diagnosis.

The Comèl-Netherton syndrome is an autosomal recessive multisystemic disorder characterized by localized or generalized congenital ichthyosis, hair shaft abnormalities, immune deficiency, and markedly elevated IgE levels. Life-threatening complications during infancy include temperature and electrolyte imbalance, recurrent infections, and failure to thrive. To study the clinical presentations of the Comèl-Netherton syndrome and its molecular cause, we ascertained 19 unrelated families of various ethnic backgrounds. Results of initial linkage studies mapped the Comèl-Netherton syndrome in 12 multiplex families to a 12 cM interval on 5q32, thus confirming genetic homogeneity of Comèl-Netherton syndrome across families of different origins. The Comèl-Netherton syndrome region harbors the SPINK5 gene, which encodes a multidomain serine protease inhibitor (LEKTI) predominantly expressed in epithelial and lymphoid tissues. Recently, recessive mutations in SPINK5 were identified in several Comèl-Netherton syndrome patients from consanguineous families. We used heteroduplex analysis followed by direct DNA sequencing to screen all 33 exons and flanking intronic sequences of SPINK5 in the affected individuals of our cohort. Mutation analysis revealed 17 distinct mutations, 15 of which were novel, segregating in 14 Comèl-Netherton syndrome families. The nucleotide changes included four non-sense mutations, eight small deletions or insertions leading to frameshift, and five splice site defects, all of which are expected to result in premature terminated or altered translation of SPINK5. Almost half of the mutations clustered between exons 2 and 8, including two recurrent mutations. Genotype-phenotype correlations suggested that homozygous nucleotide changes resulting in early truncation of LEKT1 are associated with a severe phenotype. For the first time, we used molecular data to perform prenatal testing, thus demonstrating the feasibility of molecular diagnosis in the Comèl-Netherton syndrome.

Adolescent↗
PubMed1992

Clonal expansion of p53 mutant cells is associated with brain tumour progression.

Tumour progression is a fundamental feature of the biology of cancer. Cancers do not arise de novo in their final form, but begin as small, indolent growths, which gradually acquire characteristics associated with malignancy. In the brain, for example, low-grade tumours (astrocytomas) evolve into faster growing, more dysplastic and invasive high-grade tumours (glioblastomas). To define the genetic events underlying brain tumour progression, we analysed the p53 gene in ten primary brain tumour pairs. Seven pairs consisted of tumours that were high grade both at presentation and recurrence (group A) and three pairs consisted of low-grade tumours that had progressed to higher grade tumours (group B). In group A pairs, four of the recurrent tumours contained a p53 gene mutation; in three of them, the same mutation was found in the primary tumour. In group B pairs, progression to high grade was associated with a p53 gene mutation. A subpopulation of cells were present in the low-grade tumours that contained the same p53 gene mutation predominant in the cells of the recurrent tumours that had progressed to glioblastoma. Thus, the histological progression of brain tumours was associated with a clonal expansion of cells that had previously acquired a mutation in the p53 gene, endowing them with a selective growth advantage. These experimental observations strongly support Nowell's clonal evolution model of tumour progression.

Amino Acid Sequence↗
PubMed1999

Comparative molecular genetic profiles of anaplastic astrocytomas/glioblastomas multiforme and their subsequent recurrences.

Malignant glial tumors (anaplastic astrocytomas and glioblastomas multiforme) arise mostly either from the progression of low grade precursor lesions or rapidly in a de novo fashion and contain distinct genetic alterations. There is, however, a third subset of malignant gliomas in which genetic lesions remain to be identified. Following surgical resection, all gliomas appear to have an inherent tendency to recur. Comparative molecular analysis of ten primary malignant gliomas (three anaplastic astrocytomas and seven glioblastomas multiforme) with their recurrences identified two distinct subgroups of recurrent tumors. In one group, primary tumors harbored genetic aberrations frequently associated with linear progression or de novo formation pathways of glial tumorigenesis and maintained their genetic profiles upon recurrence. In the other subset with no detectable known genetic mutations at first presentation, the recurrent tumors sustained specific abnormalities associated with pathways of linear progression or de novo formation. These included loss of genes on chromosomes 17 and 10, mutations in the p53 gene, homozygous deletion of the DMBTA1 and p16 and/ or p15 genes and amplification and/or overexpression of CDK4 and alpha form of the PDGF receptor. Recurrent tumors from both groups also displayed an abnormal expression profile of the metalloproteinase, gel A, and its inhibitor, TIMP-2, consistent with their highly invasive behavior. Delineation of the molecular differences between malignant glioblastomas and their subsequent recurrences may have important implications for the development of rational clinical approaches for this neoplasm that remains refractory to existing therapeutic modalities.

Cell Cycle Proteins↗
PubMed2003

Screening of patients with craniosynostosis: molecular strategy.

Craniosynostosis is the premature fusion of calvarial bones leading to an abnormal head shape. The craniosynostosis syndromes are clinically heterogeneous with overlapping features, which make an accurate diagnosis difficult at times. Although the clarification of a genetic lesion does not have a direct impact on patient management in many cases, there is a significant benefit in providing accurate prenatal diagnosis. Genetic counsellors are also able to offer better risk estimates of recurrences to non-manifesting carriers and their extended family members and for affected patients of reproductive age. Advances in gene discovery have shown that craniosynostosis syndromes delineated on clinical bases, with the possible exception of Apert syndrome, are genetically heterogeneous, and mutations have been found in fibroblast growth factor receptors (FGFR) 1, 2, 3 and TWIST. We surveyed 99 craniosynostosis patients at the molecular level and found mutations in 50 of them. Six novel point mutations were identified: three in FGFR2 and three in TWIST. Two Saethre-Chotzen patients with TWIST microdeletions at 7p21 were also found. The other mutations identified have been previously reported. In studying these 99 patients, we developed a diagnostic strategy for craniosynostosis testing, where sequential analysis of recurrent mutations was followed by selective sequencing. This algorithm makes testing of craniosynostosis disorders more efficient and cost-effective.

Craniosynostoses↗
PubMed1997

Familial defective apolipoprotein B-100 in hypercholesterolemic Chinese Canadians: identification of a unique haplotype of the apolipoprotein B-100 allele.

Familial defective apo B-100 (FDB) is an autosomal dominant condition resulting in hypercholesterolemia. It is generally observed in 1-6% of hypercholesterolemic subjects in Caucasian populations studied. There are, thus far, no reports characterizing the frequency and phenotype of FDB in a Chinese population. We report on the frequency of the FDB (Arg(3500)--> Gln) mutation and the associated haplotype among 160 hypercholesterolemic (TC > or = 6.2 mmol/l) Chinese Canadians including 36 subjects with a clinical diagnosis of familial hypercholesterolemia (FH). Screening for the FDB mutation was done using a mutagenic polymerase chain reaction and haplotype analysis was undertaken using eight diallelic markers and the 3'HVR marker. One Chinese Canadian clinical FH heterozygote was positive for the FDB Arg(3500)--> Gln mutation while none of the remaining non-FH hypercholesterolemic subjects (n = 124) were carriers of this mutation. Haplotype analysis in the patient positive for this mutation revealed a unique haplotype which differed from both the common haplotype of this mutation observed in Caucasians and from the only other haplotype reported in a Chinese individual. The associated haplotype included a 9-base pair deletion in the signal peptide region and the presence of three restriction sites absent in previously reported haplotypes. These data suggest that the apo B-100 Arg(3500)--> Gln mutation does not appear to be a significant factor contributing to moderate hypercholesterolemia in a Chinese population residing in Canada. However, this mutation was rarely observed among Chinese individuals with a clinical diagnosis of FH. The presence among Chinese individuals of two different haplotypes associated with this mutation, which are different from what has been described among Caucasians is compatible with multiple recurrent origins for this mutation in the Chinese population.

Adolescent↗