Genetic insights into Tietz albinism-deafness syndrome: A new dominant-negative mutation in MITF

Tietz albinism-deafness syndrome (TADS) is a rare and severe manifestation of Waardenburg syndrome that is primarily linked to mutations in MITF. In this report, we present a case of TADS resulting from a novel c.637G>C mutation in MITF (p.Glu213Gln; GenBank Accession number: NM_000248). A 3-year-old girl presented with congenital generalized hypopigmentation of the hair, skin, and irides along with complete sensorineural hearing loss. Histopathological and electron microscopy investigations indicated that this variant did not alter the number of melanocytes in the skin but significantly impaired melanosome maturation within melanocytes. Comprehensive melanin analysis revealed marked reductions in both eumelanin (EM) and pheomelanin (PM) rather than changes in the EM-to-PM ratio observed in oculocutaneous albinism. We conducted an electrophoretic mobility shift assay to investigate the binding capability of the identified variant to DNA sequences containing the E-box motif along with other known variants (p.Arg217del and p.Glu213Asp). Remarkably, all three variants exhibited dominant-negative effects, thus providing novel insights into the pathogenesis of TADS. This study sheds light on the genetic mechanisms underlying TADS and offers a deeper understanding of this rare condition and its associated mutations in MITF.

Impact of a SLC24A5 variant on the retinal pigment epithelium of a Japanese patient with oculocutaneous albinism type 6

Oculocutaneous albinism (OCA) 6 is a non-syndromic type of OCA that has distinct ocular symptoms and variable cutaneous hypopigmentation. The causative gene of OCA6 is SLC24A5, which encodes NCKX5, a K⁺ -dependent Na⁺ /Ca²⁺ exchanger 5. NCKX5 is involved in the maturation of melanosomes, but its function is still unclear. In this study, we characterized a Japanese patient with OCA6. Genetic analysis revealed compound heterozygous variants in SLC24A5, c.590 + 1dupG, and c.598G>A (p.G200R). To clarify the functional significance of the missense variant, we generated a knock-in (KI) mouse model carrying the mouse homolog of the G200R variant using the CRISPR/Cas9 system. Chemical analysis showed decreased amounts of eumelanin in the hair and skin of KI mice, while levels of benzothiazine units in pheomelanin were significantly increased in their hair. Retinal pigment was also decreased in KI mice. Notably, a histopathologic study revealed a significant pigment loss in the retinal pigment epithelium (RPE) but not in the choroid. Immunohistochemically, the expression of NCKX5 in the RPE was decreased but was maintained in the choroid of KI mice. These findings could explain the difference in phenotypic severity between eye symptoms and hypopigmentation in the skin/hair.

Expression of discoidin domain receptor 1 and E-cadherin in epidermis affects melanocyte behavior in rhododendrol-induced leukoderma mouse model

Vitiligo is a depigmentation disease characterized by gradual loss of melanin and melanocytes from the epidermis. The mechanism of melanocyte loss is not yet known. In this report, we showed that the expression of discoidin domain receptor 1 and E-cadherin, known adhesion molecules, was variable or absent in the epidermis of rhododendrol-induced leukoderma (RDIL) mice during the depigmentation process. Our findings suggest that melanocyte damage by rhododendrol promotes reduction of adhesion molecules not only in melanocytes but also in keratinocytes, and this is associated with the detachment of melanocytes from the basal layer.

Genome-wide association study identifies CDH13 as a susceptibility gene for rhododendrol-induced leukoderma

Racemic RS-4-(4-hydroxyphenyl)-2-butanol (rhododendrol; trade name: Rhododenol [RD]), which is used in topical skin-lightening cosmetics, was unexpectedly reported in Japan to induce leukoderma or vitiligo called RD-induced leukoderma (RIL) after repeated application. To our knowledge, no studies have investigated chemical-induced vitiligo pathogenesis on a genome-wide scale. Here, we conducted a genome-wide association study (GWAS) for 147 cases and 112 controls. CDH13, encoding a glycosylphosphatidylinositol-anchored protein called T-cadherin (T-cad), was identified as the strongest RIL susceptibility gene. RD sensitivity was remarkably increased by T-cad knockdown in cultured normal human melanocytes. Furthermore, we confirmed tyrosinase upregulation and downregulation of the anti-apoptotic molecules (BCL-2 and BCL-XL), suggesting that T-cad is associated with RD via tyrosinase or apoptotic pathway regulation. Finally, monobenzyl ether of hydroquinone sensitivity also tended to increase with T-cad knockdown, suggesting that the T-cad could be a candidate susceptibility gene for RIL and other chemical-induced vitiligo forms. This is the first GWAS for chemical-induced vitiligo, and it could be a useful model for studying the disease's genetic aspects.

Abstract P1-14-07: Randomized phase 3 study of anthracycline-containing regimens versus S-1 as first-line treatment for metastatic breast cancer (SELECT BC-CONFIRM)–A combined analysis of two randomized phase 3 studies (SELECT BC-CONFIRM and SELECT BC)–

Background: Anthracycline-containing regimens and taxane have been standard as the first-line chemotherapy for metastatic breast cancer (MBC). We conducted SELECT BC (randomized phase 3 study of taxane versus S-1 as first-line treatment for MBC) for evaluating the efficacy of S-1 for patients with HER2-negative MBC from 2006 to 2010 in Japan. This study demonstrated non-inferiority of S-1 in overall survival (OS) (median OS was 37.2 months in taxes group and 35.0 months in S-1 group (HR 1.05, 95% CI 0.86–1.27, p=0.015)), and superiority in health-related quality of life (HRQOL) to taxanes. S-1 was also shown as less toxic than taxane (Lancet Oncol 2016; 17: 90-98). S-1 might provide clinical benefit as first-line treatment for patients with HER2-negative MBC. To confirm this suggestion, we have conducted further study (randomized phase 3 study of anthracycline-containing regimens versus S-1 as first-line treatment for HER2-negative MBC: SELECT BC-CONFIRM) from 2011 to present, and a combined analysis of two randomized studies (SELECT-BC CONFIRM and SELECT-BC).

Methods: In SELECT BC-CONFIRM, 230 patients receiving first-line treatment for MBC were randomly assigned to either anthracycline group (n=115) or S-1 group (n=115). Anthracycline group patients received anthracycline-containing regimens (AC, EC, FAC, FEC, q3w) at the discretion of the treating physician. S-1 group patients received S-1 40–60 mg twice daily based on the patient's body surface area for 28 days on, 14-day off. The primary endpoint was OS, and secondary endpoints were progression-free survival (PFS), time to treatment failure (TTF), adverse events, HRQOL, and cost-effectiveness. The results were combined with SELECT-BC, to confirm the hypothesis that S-1 treatment is not inferior to the standard therapy (taxanes / anthracycline) for HER2-negative MBC.

Results: A combined analysis of the two studies showed that HR was 1.06, 95%CI 0.90-1.253, and p=0.0071 between the standard therapy group and S-1 group. In addition, the Bayesian posterior probability for which HR would be less than 1.333 was about 99.6%.

Conclusions: A combined analysis of SELECT BC-CONFIRM and SELECT BC clearly demonstrated that OS with S-1 was not inferior to that with the standard therapy in patients receiving first-line treatment for HER2-negative MBC. S-1 could become a standard therapy for this patient population.

Citation Format: Park Y, Akabane H, Watanabe T, Takahashi M, Sagara Y, Nishimura R, Tsurutani J, Takashima T, Fujisawa T, Hozumi Y, Uemura Y, Mukai H. Randomized phase 3 study of anthracycline-containing regimens versus S-1 as first-line treatment for metastatic breast cancer (SELECT BC-CONFIRM)–A combined analysis of two randomized phase 3 studies (SELECT BC-CONFIRM and SELECT BC)– [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-14-07.

Leukoderma induced by rhododendrol is different from leukoderma of vitiligo in pathogenesis: A novel comparative morphological study

BACKGROUND

Rhododendrol (rhododenol), an inhibitor of tyrosinase activity, is used as a skin-whitening component. Many cases of leukoderma after the application have been reported, termed rhododenol-induced leukoderma (RIL). The aim of this study was to clarify the pathogenesis of RIL morphologically through comparison with vitiligo.

METHODS

We examined 14 cases of RIL and 15 cases of vitiligo using routine histopathology and immunohistochemistry. Thirteen cases of RIL, six cases of vitiligo and specimens of the RIL mouse model were evaluated by electron microscopy.

RESULTS

There were common findings in RIL and vitiligo at the light-microscopic level: (a) vacuolar changes in the dermo-epidermal junction, (b) melanophages in the papillary dermis, (c) perifollicular lymphocyte infiltration, (d) loss or decrease of basal melanin pigment and (e) decrease of melanocytes in the lesions. The ultrastructural observations showed specific findings of RIL: (a) remaining melanocytes in depigmented lesions, (b) inhomogeneous melanization in melanocytes and (c) degenerated melanosomes in melanocytes. Some of the findings were observed in a RIL mouse model. Furthermore, it is notable that cell organelles of melanocytes were intact in our RIL cases.

CONCLUSION

Morphological changes of RIL targeting melanosomes in melanocytes without degeneration of organelles reflect the reversible clinical course of most cases.

Abstract P3-11-02: A randomized phase II trial of toremifene (120 mg) versus fulvestrant (500 mg) after prior non-steroidal aromatase inhibitor in postmenopausal women with hormone receptor-positive metastatic breast cancer (Hi-FAIR fx study)

Background: After the failure of a non-steroidal aromatase inhibitor (nsAI) for postmenopausal patients with advanced/metastatic breast cancer (BC), it is unclear which of the various kinds of endocrine monotherapy is the most appropriate. In a previous report it was found that toremifene 120 mg (TOR 120), a selective estrogen receptor modulator (SREM), was superior to steroidal AI in terms of progression-free survival after ns-AI in the Hi-FAIR ex trial. A phase II randomized trial of TOR 120 versus fulvestrant 500 mg (FUL 500), a selective estrogen receptor down regulator (SERD), was also conducted to select the most promising endocrine monotherapy after ns-AI in advanced/metastatic BC(Study registry number: UMIN000010087).

Patients and Methods: Postmenopausal women (n=106) with advanced/metastatic hormone-receptor positive BC from October 2011 to September 2014 were enrolled in this study. Fifty-three of the patients were randomly assigned to the TOR 120 (120 mg daily p.) group and 53 of the patients were randomly assigned to the FUL 500 group. In the FUL 500 group they were administered 500 mg of fulvestrant intramuscularly (im) on day 0, then 500 mg im on days 14 and 28 and every 28 days thereafter). If treatment failure occurred in either of the randomly assigned groups the patients were then removed and treated accordingly. A full analysis set was targeted for all cases that received the protocol treatment even once (TOR 120 (n=53) and FUL 500 (n=52)). The primary end point was the clinical benefit rate (CBR). The secondary end points were the objective response rate (ORR), progression-free survival (PFS), time to chemotherapy (TTCT), overall survival (OS), toxicity, and CBR, ORR and PFS after crossover of non-assigned treatment.

Results: A median follow up period of 30 months revealed that the CBR of FUL 500 (57.7%) tended to be superior to the CBR of TOR 120 (45.3%), the odds ratio (OR) was 1.70 (95% CI 0.74–3.62), and the median PFS was 7.8 months in the FUL 500 group and 5.8 months in the TOR 120 group. Moreover the hazard ratio (HR) was 0.79 (95% CI 0.52–1.21). However, there was no difference between the two groups in terms of ORR (17.7% and 15.1%, respectively), TTCT (13.3 months vs. 17.7 months, HR = 0.94 (95%CI 0.57 – 1.53)), and OS (33.4 months vs. not reached HR 1.29; 95% CI 0.80–2.09). At the cross-over phase, 33 and 24 patients after failure of assigned treatment were treated with FUL 500 and TOR 120, respectively. The CBR and PFS of FUL 500 after TOR 120 was better than that of TOR 120 after FUL 500 (CBR; 42.4% vs. 20.8%, OR = 0.33, 95%CI 0.09 – 1.11, median PFS; 6.2 months vs. 3.4 months; HR = 1.95, 95%CI 1.08–3.51). No difference between the two groups was observed in PFS from randomization to the end of the crossover phase. Moreover, there were few severe adverse events in either of the two groups.

Conclusions: FUL 500 used as a subsequent endocrine therapy for advanced/metastatic BC patients who failed ns-AI could potentially be more effective than TOR 120. However, the efficacy of SERM after failure of FUL 500 may be limited.

Citation Format: Nishimura R, Yamamoto Y, Narui K, Kijima Y, Hozumi Y, Ikeda M, Takao S, Ohtani S, Iwase H. A randomized phase II trial of toremifene (120 mg) versus fulvestrant (500 mg) after prior non-steroidal aromatase inhibitor in postmenopausal women with hormone receptor-positive metastatic breast cancer (Hi-FAIR fx study) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-11-02.

Measurement and comparison of individual external doses of high-school students living in Japan, France, Poland and Belarus-the 'D-shuttle' project

Twelve high schools in Japan (of which six are in Fukushima Prefecture), four in France, eight in Poland and two in Belarus cooperated in the measurement and comparison of individual external doses in 2014. In total 216 high-school students and teachers participated in the study. Each participant wore an electronic personal dosimeter 'D-shuttle' for two weeks, and kept a journal of his/her whereabouts and activities. The distributions of annual external doses estimated for each region overlap with each other, demonstrating that the personal external individual doses in locations where residence is currently allowed in Fukushima Prefecture and in Belarus are well within the range of estimated annual doses due to the terrestrial background radiation level of other regions/countries.

Abstract P5-18-01: A randomized clinical trial of postoperative adjuvant therapy for elderly breast cancer patients: Conditions of obtaining informed consent and reasons for declining participation

Background: There are few randomized clinical trials examining adjuvant treatment in elderly breast cancer patients. While obtaining informed consent is essential for participation in clinical studies, there is little information on the frequency of agreement to participate among elderly patients. Furthermore, elderly patients might have specific reasons to decline participation.

Patients and Method: The National Surgical Adjuvant Study of Breast Cancer 07 (N-SAS BC 07) is a randomized clinical trial in women over 70 years with HER2-positive primary breast cancer. The primary aim was to investigate the benefit of trastuzumab monotherapy compared with the combination of trastuzumab and chemotherapy. Key inclusion criteria were as follows: women between 70 and 80 years old with HER2-positive breast cancer; underwent curative operation; stage I to IIIA; with sufficient organ function. Patients were randomized to receive either trastuzumab plus chemotherapy or trastuzumab monotherapy. The primary endpoint was disease-free survival, and the secondary endpoints were overall survival, relapse-free survival, safety, health-related quality of life, and cost effectiveness (NCT01104935). It was not possible to predict the number of patients who would agree to participate. In order to comprehensively assess the effect of postoperative adjuvant therapy, we evaluated the reasons why eligible patients declined to participate. The patients were registered in a cohort study to prospectively evaluate the subsequent treatment options and prognosis (07-Cohort). This study examined the obtaining of informed consent for N-SAS BC 07 and the reasons for declining participation, and compared the clinicopathological backgrounds between the N-SAS BC 07 and 07-Cohort groups.

Results: 398 eligible patients have been recruited. Informed consent to participate in N-SAS BC 07 has been obtained from 275 patients (69%) and 123 patients (31%) who declined to participate in the RCT have been registered in the 07-Cohort. The common reasons to decline participation in the RCT were "cannot choose the treatment option (55%)", "refused chemotherapy (16%)", "wanted chemotherapy (9%)", "anxious about clinical studies (9%)" and "family opposition (8%)". The mean ages of the patients in N-SAS BC 07 and 07-Cohort were 73.9 and 74.6 years old, respectively. There were no differences in stage, surgical procedure, lymph node metastasis, or co-morbidities between the groups. ER-positive rate was higher in 07-Cohort group compared with N-SAS BC 07 group (53% vs. 37%, p=0.017, χ2 test).

Conclusion: While we expected the number of registrants to be small, since N-SAS BC 07 investigated whether elderly patients with HER2-positive breast cancer should undergo chemotherapy, almost 70% of the patients accepted informed consent. The most common reason to decline participation in N-SAS BC 07 was "cannot choose the treatment option" and the majority refused chemotherapy. Furthermore, ER-positivity was higher in the 07-Cohort group, which suggested that ER expression in the patients with HER2-positive breast cancer might influence their decision to participate in the study or to choose the treatment option.

Citation Format: Sagara Y, Sawaki M, Taira N, Saito T, Kashiwaba M, Iwata H, Kobayashi K, Nakayama T, Bando H, Mizuno T, Yamamoto Y, Tsuneizumi M, Takahashi M, Yamaguchi M, Kawashima H, Takashima T, Uemura Y, Hozumi Y, Sagawa N, Mukai H, Ohashi Y. A randomized clinical trial of postoperative adjuvant therapy for elderly breast cancer patients: Conditions of obtaining informed consent and reasons for declining participation. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-18-01.

Abstract P4-11-09: A randomized controlled trial of postoperative adjuvant therapy for elderly breast cancer patients: Comparison of health-related quality of life between clinical trial participants and decliners

Background: Health-related quality of life (HRQoL) is one of the important outcomes in cancer control trials and has increasingly become the one of the primary foci. Obtaining informed consent from participants is essential for participation in randomized controlled trials (RCTs), but the participation in these RCTs may directly influence HRQoL, because treatment options are determined according to the allocation schedule. To date, only a few studies have compared HRQoL between clinical trial participants and decliners.

Patients and Method: The National Surgical Adjuvant Study of Breast Cancer 07 (N-SAS BC 07) is a randomized controlled trial in women with HER2-positive primary breast cancer who are over 70 years of age. The primary aim was to investigate the benefit of trastuzumab monotherapy compared with combination therapy using trastuzumab and chemotherapy. The study concept and design were published in concept paper (Sawaki M. et al., Jpn J Clin Oncol. 2011). In this study, patients were randomized to receive either trastuzumab plus chemotherapy or trastuzumab monotherapy. The primary endpoint was disease-free survival, and the secondary endpoints were overall survival, relapse-free survival, safety, HRQoL, comprehensive geriatric assessment (CGA) and cost effectiveness (protocol ID; NCT01104935).

HRQoL and CGA were assessed at registration (baseline), 2 month, 1 year, and 3 years after the start of protocol treatments using the Functional Assessment of Cancer Therapy-General (FACT-G), Hospital Anxiety and Depression Scale (HADS), EuroQol 5 Dimension (EQ-5D), Tokyo Metropolitan Institute of Gerontology (TMIG) index of competence, and the Philadelphia Geriatric Center (PGC) Morale Scale.

The patients who declined to participate in N-SAS BC 07 were registered in a cohort study to prospectively evaluate the subsequent treatment options and prognosis (07-Cohort). The same questionnaire that was used in N-SAS BC 07 was used in 07-Cohort to evaluate HRQoL and CGA at entry.

Results: Patients were enrolled from October 2012 to October 2016. During this period, 275 and 123 patients were registered in N-SAS BC 07 and 07-Cohort, respectively. The mean age at entry of the patients in the N-SAS BC 07 and 07-Cohort groups was 73.9 and 74.6 years, respectively. The questionnaire response rates at baseline in the patients in N-SAS BC 07 and 07-Cohort groups were 89% and 82%, respectively. There were no significant differences in FACT-G, HADS, EQ-5D, or TMIG index of competence at baseline between the groups, but the mean (standard deviation) scores of PGC Morale Scale in N-SAS BC 07 and 07-Cohort groups were 10.8 (3.3) and 9.9 (3.7), respectively, with the scores being significantly greater in the N-SAS BC 07 group (p=0.020, t-test).

Conclusion: The PGC Morale Scale provides a multidimensional approach to assess the psychological state of older people. This study indicated that participation in the RCT did not affect the baseline QoL of elderly patients but suggested that the baseline QoL of the RCT participants was better than decliners.

Citation Format: Saito T, Sawaki M, Hozumi Y, Sagawa N, Iwata H, Kashiwaba M, Kawashima H, Kobayashi K, Taira N, Takashima T, Takahashi M, Tsuneizumi M, Nakayama T, Baba S, Bando H, Mizuno T, Yamaguchi M, Yamamoto Y, Uemura Y, Ohashi Y, Mukai H. A randomized controlled trial of postoperative adjuvant therapy for elderly breast cancer patients: Comparison of health-related quality of life between clinical trial participants and decliners. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-11-09.

Topical Vitamin D3Is Effective in Treating Senile Warts Possibly by Inducing Apoptosis

Vitamin D3 ointments containing active forms of vitamin D3 are widely used to treat inflammatory keratotic dermatoses such as psoriasis. Senile wart or seborrheic keratosis is a benign tumor which occurs mainly in the elderly. It has traditionally been treated with surgical procedures, freezing with liquid nitrogen, or laser therapy. We treated senile warts with topical vitamin D3 ointments (tacalcitol, calcipotriol or maxacalcitol). Out of 116 cases treated for 3 to 12 months, 35 (30.2%) showed complete disappearance or more than an 80% decrease in the volume of the tumor, 54 cases (46.6%) showed a decrease in the volume between 40 and 80%, and no remarkable changes or decreases of less than 40% were seen in 27 cases (23.3%). The tumors faded without any inflammatory changes such as erythema or swelling. An organ culture experiment using senile wart as a material with several concentrations of tacalcitol revealed that tacalcitol induced apoptosis in the tissue. On the other hand, only sporadic apoptotic cells were seen in the controls (p<0.001). Vitamin D3 may affect senile warts by inducing apoptosis. Clearance of senile warts, especially on exposed areas without pain, may improve the quality of life (QOL) of the elderly.

Survival of HER2-positive primary breast cancer patients treated by neoadjuvant chemotherapy plus trastuzumab: a multicenter retrospective observational study (JBCRG-C03 study)

We investigated the disease-free survival (DFS) of HER2-positive primary breast cancer patients treated with neoadjuvant chemotherapy plus trastuzumab, as well as predictive factors for DFS and pathologic response. Data from 829 female patients treated between 2001 and 2010 were collected from 38 institutions in Japan. Predictive factors were evaluated using multivariate analyses. The 3-year DFS rate was 87 % [95 % confidence interval (CI) 85-90]. The pathologic complete response (pCR: ypT0/is + ypN0) rate was 51 %. The pCR rate was higher in the ER/PgR-negative patients than in the ER/PgR-positive patients (64 vs. 36 %, P < 0.001). Patients with pCR showed a higher DFS rate than patients without pCR (93 vs. 82 %, P < 0.001). Multivariate analysis revealed three independent predictors for poorer DFS: advanced nodal stage [hazard ratio (HR) 2.63, 95 % CI 1.36-5.21, P = 0.004 for cN2-3 vs. cN0], histological/nuclear grade 3 (HR 1.81, 95 % CI 1.15-2.91, P = 0.011), and non-pCR (HR 1.98, 95 % CI 1.22-3.24, P = 0.005). In the ER/PgR-negative dataset, non-pCR (HR 2.63, 95 % CI 1.43-4.90, P = 0.002) and clinical tumor stage (HR 2.20, 95 % CI 1.16-4.20, P = 0.017 for cT3-4 vs. cT1-2) were independent predictors for DFS, and in the ER/PgR-positive dataset, histological grade of 3 (HR 3.09, 95 % CI 1.48-6.62, P = 0.003), clinical nodal stage (HR 4.26, 95 % CI 1.53-13.14, P = 0.005 for cN2-3 vs. cN0), and young age (HR 2.40, 95 % CI 1.12-4.94, P = 0.026 for ≤40 vs. >40) were negative predictors for DFS. Strict pCR (ypT0 + ypN0) was an independent predictor for DFS in both the ER/PgR-negative and -positive datasets (HR 2.66, 95 % CI 1.31-5.97, P = 0.006 and HR 3.86, 95 % CI 1.13-24.21, P = 0.029, respectively). These results may help assure a more accurate prognosis and personalized treatment for HER2-positive breast cancer patients.