An autopsy case of GM1 gangliosidosis type II in a patient who survived a long duration with artificial respiratory support.

GM1 gangliosidosis is a storage disorder with autosomal recessive inheritance caused by deficiency of ß-galactosidase (GLB1), which is a lysosomal hydrolase, due to mutations in GLB1. We describe here an autopsy case of GM1 gangliosidosis in a female patient who survived for 38 years with a long period of artificial respiratory support (ARS). She was born after a normal pregnancy and delivery. Although development was normal until one year old, she was unable to walk at two years old and started having seizures by nine years old. At 21 years old, she became unable to communicate and was bed-ridden. At 36 years old, she suffered from pneumonia and required ARS. She died of pneumonia at 40 years old. Neuropathological examination revealed severe atrophy, predominantly found in the frontal lobes. Microscopically, severe gliosis and neuronal loss were observed in the cerebral cortex, putamen, cerebellum, the latter including Purkinje cell and granule cell layers. The hippocampus was relatively preserved. Severe neuronal swelling was observed in the limbic regions and stored a material in these neurons negative for periodic acid-Schiff (PAS). A PAS-positive granular storage material in neurons and macrophages was mainly observed in the brainstem and limbic regions. Exome analysis showed a known c.152T>C (p.I51T) variant that has been described in type III patients and a novel c.1348-2A>G variant in GLB1. Detailed analysis of reverse transcription-polymerase chain reaction products of GLB1 mRNA revealed that these variants were present in a compound heterozygous state. In our case, clinical features and neuropathological findings were most consistent with type II, although the entire course was longer than any previously reported cases. This may be explained by the residual enzyme activity in this patient whose severity lay between types II and III. Our finding of relative preservation of the limbic regions suggests that neuronal loss in GM1 gangliosidosis has regional selectivity.

Impact of five-tiered Gleason grade groups on prognostic prediction in clinical stage T3 prostate cancer undergoing high-dose-rate brachytherapy.

BACKGROUND: We evaluated a five-tiered Gleason grade groups arising from the 2014 International Society of Urological Pathology consensus conference on prognostic prediction in clinical stage T3a (extracapsular invasion) and T3b (seminal vesicle involvement) prostate cancer undergoing high-dose-rate brachytherapy (HDR-BT). METHODS: From November 2003 to December 2012, 283 patients with stage T3 prostate cancer received HDR-BT and external beam radiation therapy (EBRT) with long-term androgen deprivation therapy (ADT). Of these, 203 (72%) and 80 (28%) patients had stage T3a and T3b disease, respectively. The mean dose to 90% of the planning target volume was 7.5 Gy/fraction of HDR-BT. After five fractions, EBRT with 10 fractions of 3 Gy was administered. All patients first underwent ≥6 months of neoadjuvant ADT, and adjuvant ADT continued for 36 months. Median follow-up was 74 months from the start of radiotherapy. RESULTS: The 10-year biochemical recurrence (BCR) -free rate for stage T3a and T3b disease was 79% and 64%, respectively (P = 0.0083). The 10-year cancer-specific survival (CSS) rate for stage T3a and T3b was 96% and 91%, respectively (P = 0.0305). Although grade groups ≥4 were independent predictors for BCR in cT3a patients (P = 0.0270), they failed to significantly predict prostate cancer-specific mortality (PCSM) among cT3a patients. Among cT3b patients, grade group 5 was a significant predictor of both BCR (P = 0.0017) and PCSM (P = 0.0233). Among stage T3a patients, no significant difference existed in 10-year CSS between grade groups 5 and 4 (94% vs 97%, P = 0.3960). In contrast, grade group 5 had a significantly worse outcome in 10-year CSS than grade group 4 among stage T3b patients (74% vs 100%, P = 0.0350). CONCLUSIONS: Stage T3a patients with grade groups 4/5 and stage T3b with grade group 4 had fairly low PCSM risk. Approximately one of four patients among stage T3b patients with grade group 5 showed PCSM after combined HDR-BT and EBRT with long-term ADT. Stage T3b patients with grade group 5 may have a greater risk for PCSM.

Case report: Electrocardiographic changes in pembrolizumab-induced fatal myocarditis.

Immune checkpoint inhibitor (ICI)-induced myocarditis is rare but fatal. Because of the rapid course of ICI-induced myocarditis, understanding of clinical course is only possible through information from case reports. We report a case of pembrolizumab-induced myocarditis in which we were able to document the course of electrocardiographic changes from onset to death. A 58-year-old woman with stage IV lung adenocarcinoma, who had completed her first cycle of pembrolizumab, carboplatin, and pemetrexed, was admitted with pericardial effusion. She underwent pericardiocentesis after admission. A second cycle of chemotherapy was administered 3 weeks after the first cycle. Twenty-two days after admission, she developed a mild sore throat and tested positive for SARS-CoV-2 antigen. She was diagnosed with mild coronavirus disease 2019 (COVID-19), isolated, and treated with sotrovimab. Thirty-two days after admission, an electrocardiogram showed monomorphic ventricular tachycardia (VT). Suspecting myocarditis caused by pembrolizumab, the patient was started on daily methylprednisolone after coronary angiography and endocardial biopsy. Eight days after the start of methylprednisolone administration, she was considered to have passed the acute stage. However, four days later, R-on-T phenomenon triggered polymorphic VT and she died. The impact of viral infections such as COVID-19 on patients be treated with immune checkpoint inhibitors is still unknown and we need to be careful with systemic management after viral infections.

A rare case of multiple paragangliomas in the head and neck, retroperitoneum and duodenum: A case report and review of the literature.

Pheochromocytomas and paragangliomas (PGLs) are rare non-epithelial neuroendocrine neoplasms of the adrenal medulla and extra-adrenal paraganglia respectively. Duodenal PGL is quite rare and there are only two previous reports. Herein, we report a case of multiple catecholamines (CAs)-producing PGLs in the middle ear, retroperitoneum, and duodenum, and review the literature of duodenal PGLs. A 40-year-old man complained right-ear hearing loss, and an intracranial tumor was suspected. Magnetic resonance imaging of the head revealed a 3-cm mass at the right transvenous foramen, which was surgically resected following preoperative embolization. The pathological diagnosis was a sympathetic PGL of the right middle ear. Six years later, family history of PGL with germline mutation of succinate dehydrogenase complex iron sulfur subunit B, SDHB: c.268C>T (p.Arg90Ter) was clarified. The patient had elevated levels of plasma and urine CAs again. Abdominal computed tomography scanning revealed two retroperitoneal tumors measuring 30-mm at the anterior left renal vein and 13-mm at near the ligament of Treitz. The larger tumor was laparoscopically resected, but the smaller tumor was not identified by laparoscopy. After the operation, the patient remained hypertensive, and additional imaging tests suggested a tumor localized in the duodenum. The surgically resected tumor was confirmed to be a duodenal PGL. After that, the patient remained hypertension free, and urinary levels of noradrenaline and normetanephrine decreased to normal values. No recurrence or metastasis has been found at 1 year after the second operation. CAs secretion from PGLs in unexpected location, like the duodenum of our patient, may be overlooked and leads to a hypertensive crisis. In such cases, comprehensive evaluation including genetic testing, fluorodeoxyglucose-positron emission tomography scanning, and measurement of CAs will be useful for detecting PGLs. Most previous reports on duodenal PGL were gangliocytic PGL which has been renamed composite gangliocytoma/neuroma and neuroendocrine tumor, and defined the different tumor from duodenal PGL. We reviewed and discussed duodenal PGLs in addition to multiple PGLs associated with SDHB mutation.

Prognostic values of L-type amino acid transporter 1 and CD98hc expression in breast cancer.

AIMS: L-type amino acid transporter 1 (LAT1) is a major Na+-independent neutral amino acid transporter, forming a complex with CD98hc. The aim of this study is to investigate the significance of LAT1 and CD98hc in invasive breast cancer. METHODS: LAT1 and CD98hc expression was immunohistochemically assessed in 280 invasive breast cancers and analysed for association with clinicopathological features. RESULTS: High levels of LAT1 and CD98hc were observed in triple-negative breast cancers (TNBCs) possessing negative immunoreactivity with oestrogen receptor, progesterone receptor and human epidermal growth factor receptor 2, compared with non-TNBCs (NTNBCs), and were associated with lymph-node metastasis and higher nuclear grade. The high-LAT1-expression group showed a poor prognosis in NTNBC and TNBC, however, high-CD98hc-expression group showed a poor prognosis only in NTNBC. LAT1 and CD98hc expression could be the prognostic factors in univariate analyses, but not in multivariate analyses. Further, we found that invasive tumour components showed higher LAT1 and CD98hc expression than non-invasive tumour components. CONCLUSIONS: LAT1 and CD98hc may possess prognostic values in invasive breast cancer. LAT1 may be linked with cancer cell activities and disease progression in breast cancer.

Cytopathic effects and local immune responses in repeated neoadjuvant HSV-tk + ganciclovir gene therapy for prostate cancer.

OBJECTIVE: Cytopathic effects and local immune response were analyzed histologically in prostatic cancer (PCa) with in situ herpes simplex virus-thymidine kinase (HSV-tk)/ganciclovir (GCV) gene therapy (GT). METHODS: Four high-risk PCa patients who received HSV-tk/GCV GT were investigated. After two cycles of intraprostatic injection of HSV-tk and administration of GCV, radical prostatectomy was performed. Formalin-fixed, paraffin-embedded sections were evaluated using immunohistochemistry. PCa with hormone therapy (HT, n=3) or without neoadjuvant therapy (NT, n=4) that were equivalent in terms of risk were also examined as reference. Immunoreactively-positive cells were counted in at least three areas in cancer tissue. Labeling indices (LI) were calculated as percentage values. RESULTS: ssDNA LI in GT increased, indicating apoptosis, as well as tumor-infiltrating lymphocytes and CD68-positive macrophages, compared with their biopsies. GT cases showed significantly higher numbers of single-stranded DNA (ssDNA) LI, CD4/CD8-positive T cells and CD68-positive macrophages including M1/M2 macrophages than HT or NT cases. However, there was no significant difference in CD20-positive B cells among the types of case. There were strong correlations between CD8+ T cells and CD68+ macrophages (ρ=0.656, p<0.0001) as well as CD4+ T cells and CD20+ B cells (ρ=0.644, p<0.0001) in PCa with GT. CONCLUSIONS: Enhanced cytopathic effect and local immune response might be indicated in PCa patients with HSV-tk/GCV gene therapy.

[A case of recurrent invasive thymic cancer showing a stable disease to carboplatin plus paclitaxel].

A 56-year-old man was admitted to our hospital because of increasing chest discomfort and abnormal chest shadow. Computed tomography (CT) of the chest revealed an anterior mediastinal mass, pleural dissemination and lung metastasis. Percutaneus needle biopsy guided by CT showed that the mass was advanced thymic cancer (stage IV b according to the classification proposed by Masaoka). After failure of combination chemotherapy of cisplatin, vincristine, doxorubicin and etoposide (CODE), he received 4 cycles of carboplatin plus paclitaxel and then achieved confirmed stable disease. In terms of toxicity profile, grade 4 anemia, grade 2 leucopenia and neutropenia were observed, and particularly non-severe toxicity was not observed in terms of non-hematologic toxicity. Carboplatin plus paclitaxel can be an active agent against pretreated thymic cancer.

H3F3A mutant allele specific imbalance in an aggressive subtype of diffuse midline glioma, H3 K27M-mutant.

Diffuse midline glioma, H3 K27M-mutant is a lethal brain tumor located in the thalamus, brain stem, or spinal cord. H3 K27M encoded by the mutation of a histone H3 gene such as H3F3A plays a pivotal role in the tumorigenesis of this type of glioma. Although several studies have revealed comprehensive genetic and epigenetic profiling, the prognostic factors of these tumors have not been identified to date. In various cancers, oncogenic driver genes have been found to exhibit characteristic copy number alterations termed mutant allele specific imbalance (MASI). Here, we showed that several diffuse midline glioma, H3 K27M-mutant exhibited high variant allele frequency (VAF) of the mutated H3F3A gene using droplet digital polymerase chain reaction (ddPCR) assays. Whole-genome sequencing (WGS) revealed that these cases had various copy number alterations that affected the mutant and/or wild-type alleles of the H3F3A gene. We also found that these MASI cases showed a significantly higher Ki-67 index and poorer survival compared with those in the lower VAF cases (P < 0.05). Our results indicated that the MASI of the H3F3A K27M mutation was associated with the aggressive phenotype of the diffuse midline glioma, H3 K27M-mutant via upregulation of the H3 K27M mutant protein, resulting in downregulation of H3K27me3 modification.

Reprint of: Stromogenic prostatic carcinoma pattern (carcinomas with reactive stromal grade 3) in needle biopsies predicts biochemical recurrence-free survival in patients after radical prostatectomy.

We previously reported that reactive stromal grading in radical prostatectomies is a predictor of recurrence and that reactive stromal grading 0 and 3 are associated with lower biochemical recurrence-free survival rates than reactive stromal grading 1 and 2. We explored the prognostic significance of reactive stromal grading in preoperative needle biopsies. At Baylor College of Medicine, 224 cases of prostatic carcinoma were diagnosed by needle biopsy. Reactive stromal grading was evaluated on hematoxylin-eosin (H&E)-stained sections on the basis of previously described criteria: grade 0, with 0% to 5% reactive stroma; grade 1, 6% to 15%; grade 2, 16% to 50%; grade 3, 51% to 100%, or at least a 1:1 ratio between glands and stroma. Kaplan-Meier and Cox proportional hazard analyses were used. Reactive stromal grading distribution was as follows: reactive stromal grading 0, 1 case (0.5%); reactive stromal grading 1, 149 cases (66.5%); reactive stromal grading 2, 59 cases (26.3%); reactive stromal grading 3, 15 cases (6.7%). Reactive stromal grading in biopsies was correlated with adverse clinicopathologic parameters in the prostatectomy. Patients with reactive stromal grading 1 and 2 had better survival than those with 0 and 3 (P = .0034). Reactive stromal grading was an independent predictor of recurrence (hazard ratio = 1.953; P = .0174). Reactive stromal grading is independent of Gleason 4 + 3 and 3 + 4 in patients with a Gleason score of 7. Quantitation of reactive stroma and recognition of the stromogenic carcinoma in H&E-stained biopsies is useful to predict biochemical recurrence in prostate carcinoma patients independent of Gleason grade and prostate-specific antigen.

Reclassification of the current tumor, node, metastasis staging in pT3 renal cell carcinoma.

OBJECTIVES: Although the tumor, node, metastasis (TNM) staging classification of renal cell carcinoma (RCC) was last modified in 2002, pT3 staging has continued to be debated. It has been suggested that direct adrenal gland involvement and pT3b with pT3a should be reclassified. This study accordingly explores reclassification of the current 2002 TNM staging in pT3 RCCs. METHODS: A total of 111 patients with pT3 RCC who underwent radical nephrectomy at our institution between March 1972 and February 2006 were enrolled in this study. Histological samples were reviewed by a single pathologist. Disease-specific survival was compared according to reclassification as pT3a with perirenal fat involvement only (pT3a-fat), pT3a with adrenal gland involvement (pT3a-ad), pT3b without pT3a factors (pT3b-only), pT3b with pT3a factors (pT3b with pT3a), or pT3c. RESULTS: Seven patients were identified as having pT3a-ad and 20 patients as having pT3b with pT3a. The mean disease-specific survival times in pT3a-fat and pT3b-only were significantly longer: 124.1 +/- 13.2 (SE) months and 70.9 +/- 9.1 (SE) months, respectively, compared with 24.7 +/- 6.7 (SE) months in pT3a-ad (P = 0.0004 and 0.0010, respectively), and 25.0 +/- 4.4 (SE) months in pT3b with pT3a (P = 0.0009 and 0.0032, respectively). On multivariate analysis, the presence of direct ipsilateral adrenal gland involvement was recognized as a predictor of poor prognosis (P = 0.0331). CONCLUSIONS: Direct ipsilateral adrenal gland involvement for patients with pT3a, and perirenal fat or adrenal gland involvement for patients with pT3b should be reclassified nearly to pT4.

Stromogenic prostatic carcinoma pattern (carcinomas with reactive stromal grade 3) in needle biopsies predicts biochemical recurrence-free survival in patients after radical prostatectomy.

We previously reported that reactive stromal grading in radical prostatectomies is a predictor of recurrence and that reactive stromal grading 0 and 3 are associated with lower biochemical recurrence-free survival rates than reactive stromal grading 1 and 2. We explored the prognostic significance of reactive stromal grading in preoperative needle biopsies. At Baylor College of Medicine, 224 cases of prostatic carcinoma were diagnosed by needle biopsy. Reactive stromal grading was evaluated on hematoxylin-eosin (H&E)-stained sections on the basis of previously described criteria: grade 0, with 0% to 5% reactive stroma; grade 1, 6% to 15%; grade 2, 16% to 50%; grade 3, 51% to 100%, or at least a 1:1 ratio between glands and stroma. Kaplan-Meier and Cox proportional hazard analyses were used. Reactive stromal grading distribution was as follows: reactive stromal grading 0, 1 case (0.5%); reactive stromal grading 1, 149 cases (66.5%); reactive stromal grading 2, 59 cases (26.3%); reactive stromal grading 3, 15 cases (6.7%). Reactive stromal grading in biopsies was correlated with adverse clinicopathologic parameters in the prostatectomy. Patients with reactive stromal grading 1 and 2 had better survival than those with 0 and 3 (P = .0034). Reactive stromal grading was an independent predictor of recurrence (hazard ratio = 1.953; P = .0174). Reactive stromal grading is independent of Gleason 4 + 3 and 3 + 4 in patients with a Gleason score of 7. Quantitation of reactive stroma and recognition of the stromogenic carcinoma in H&E-stained biopsies is useful to predict biochemical recurrence in prostate carcinoma patients independent of Gleason grade and prostate-specific antigen.

CD109, a negative regulator of TGF-ß signaling, is a putative risk marker in diffuse large B-cell lymphoma.

CD109 is a glycosylphosphatidylinositol-anchored glycoprotein that negatively regulates TGF-ß signaling. CD109 was originally identified in hematopoietic tumors; however, the significance of CD109 in hematopoietic malignancies remains unclear. Here, we study the association of CD109 with diffuse large B-cell lymphoma (DLBCL) prognosis. Eighty-four DLBCL specimens were immunohistochemically analyzed for CD109 expression, and 31 and 53 cases were classified into low- and high-CD109 expression groups, respectively. CD109 expression was not associated with overall survival using the Kaplan-Meier analysis and log-rank tests (P = 0.17); however, a significant association was observed between high-CD109 expression and low-1-year survival (P = 0.01). Moreover, in combination with the revised International Prognostic Index (R-IPI), R-IPI-poor/CD109-high was associated with poorer prognosis compared with R-IPI-poor alone. We assessed TGF-ß signaling in CD109-depleted Nalm6 cells (a human B-lymphoblastic leukemia/lymphoma cell line), and found prolonged Smad2 phosphorylation compared with control cells after TGF-ß1 stimulation, suggesting that CD109 attenuates TGF-ß1 signaling in human B-cell tumors. These results suggest that CD109 is a putative biomarker for identifying a high-risk group among DLBCL patients.

A bioinformatics-to-clinic sequential approach to analysis of prostate cancer biomarkers using TCGA datasets and clinical samples: a new method for precision oncology?

Biomarker-driven cancer therapy has met with significant clinical success. Identification of a biomarker implicated in a malignant phenotype and linked to poor clinical outcome is required if we are to develop these types of therapies. A subset of prostate adenocarcinoma (PACa) cases are treatment-resistant, making them an attractive target for such an approach. To identify target molecules implicated in shorter survival of patients with PACa, we established a bioinformatics-to-clinic sequential analysis approach, beginning with 2-step in silico analysis of a TCGA dataset for localized PACa. The effect of candidate genes identified by in silico analysis on survival was then assessed using biopsy specimens taken at the time of initial diagnosis of localized and metastatic PACa. We identified PEG10 as a candidate biomarker. Data from clinical samples suggested that increased expression of PEG10 at the time of initial diagnosis was linked to shorter survival time. Interestingly, PEG10 overexpression also correlated with expression of chromogranin A and synaptophysin, markers for neuroendocrine prostate cancer, a type of treatment-resistant prostate cancer. These results indicate that PEG10 is a novel biomarker for shorter survival of patients with PACa. Also, PEG10 expression at the time of initial diagnosis may predict focal neuroendocrine differentiation of PACa. Thus, PEG10 may be an attractive target for biomarker-driven cancer therapy. Thus, bioinformatics-to-clinic sequential analysis is a valid tool for identifying targets for precision oncology.

[8-month neoadjuvant hormonal therapy before radical prostatectomy for high-risk prostate cancer].

PURPOSE: To evaluate the clinicopathological outcomes of 8 months of neoadjuvant hormonal therapy (NHT) prior to radical prostatectomy for high-risk prostate cancer. PATIENTS AND METHODS: A multi-institutional prospective trial was performed between July 2000 and May 2003 involving high-risk prostate cancer patients without metastasis, including 21 who received 8 months of NHT before radical prostatectomy. High-risk group was defined as clinical stage > or =T2c and/or prostate-specific antigen (PSA) >20 ng/ml and/or Gleason score > or =8. PSA values were considered elevated (biochemical failure) if values of 0.1 ng/ml or greater were obtained. RESULTS: Median of initial PSA levels before prostate biopsy was 27.6 ng/ml (8.5-80.7 ng/ml), and median of pre-operative PSA levels after NHT was 0.28 ng/ml (0.02-4.2 ng/ml). There were 5 patients (23.8%) with lower limit of PSA detection (less than 0.02 ng/ml) in 8 months after NHT. The clinical T stage was T1c in 9 patients (42.9%), T2a-b in 8 patients (38.1%), T2c in 3 patients (14.3%), and T3a in 1 patient (4.8%). The median follow-up was 25 months (range 4 to 37). There were 2 patients (9.5%) in pT0, 5 patients (23.8%) with positive surgical margin, 5 patients (23.8%) with extracapsular extension (ECE) and 3 patients (14.3%) with seminal vesicle involvement (SVI). Biochemical failure was occurred in 9 of 21 (42.9%) including of one pT0. Range of time to postoperative biochemical failure was 2 to 25 months (median 6 months) and most of biochemical failure was found within 12 months after surgery. Biochemical failure rate was significantly higher in patient with positive SVI (p = 0.0308) and higher in patients with pre-operative PSA levels of more than 0.1 ng/ml (p = 0.0836), positive ECE (p = 0.0545) and positive surgical margin (p = 0.0545). CONCLUSION: Biochemical failure was frequent after this combined treatment, even in a pT0 case. Long-term follow-up of patients is needed to assess the impact of this therapy on mortality.

High expression of REV7 is an independent prognostic indicator in patients with diffuse large B-cell lymphoma treated with rituximab.

REV7 is a multifunctional protein involved in DNA damage tolerance, cell-cycle regulation, gene expression, and carcinogenesis. Although its expression is reportedly associated with poor prognosis in human solid tissue cancers, the significance of REV7 expression in hematopoietic malignancies is unclear. This study evaluated the prognostic significance of REV7 expression in patients with diffuse large B-cell lymphoma (DLBCL) treated with rituximab-combined chemotherapy. Using immunohistochemistry, we analyzed 83 specimens of de novo DLBCL [38 germinal center B-cell-like (GCB) and 45 non-GCB DLBCLs] treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone for REV7 expression. Aberrant REV7 expression was detected in DLBCL cell nuclei. High REV7 expression was associated with significantly shorter overall survival (OS) and progression-free survival (PFS) using Kaplan-Meier analysis and log-rank tests (P < 0.01 and P < 0.01, respectively). Multivariate analysis revealed that REV7 expression is an independent prognostic factor for both OS and PFS. Additionally, when patients were divided into four groups using a combination of REV7 expression and international prognostic index (IPI) or Bcl-2 expression, REV7(High)/IPI(Poor) and REV7(High)/Bcl-2(High) patients showed the poorest outcome. These results indicate that REV7 may be a useful biomarker to predict the prognosis of patients with DLBCL treated with rituximab.

L-Type amino acid transporter 1 (LAT1) expression in lymph node metastasis of gastric carcinoma: Its correlation with size of metastatic lesion and Ki-67 labeling.

L-Type amino acid transporter 1 (LAT1) is one of the major amino acid transporters. High levels of LAT1 expression have been reported in various tumors, which can act as a novel prognostic marker. Previously, we demonstrated that LAT1 is highly expressed in advanced gastric carcinoma with lymph node metastasis, and proposed that LAT1 is an independent prognostic factor in non-scirrhous gastric carcinoma. The aim of the present study was to investigate the relationship between LAT1 expression and the size of lymph node metastatic lesions in gastric carcinoma. LAT1 and Ki-67 expression was immunohistochemically analyzed in 64 cases of advanced gastric carcinoma with lymph node metastasis. LAT1 expression in the metastatic lymph nodes was correlated with that in the primary lesions. The high LAT1 expression group showed a larger size of metastatic lesion and a higher Ki-67 labeling index than the low LAT1 expression group. LAT1 expression had a weak association with Ki-67 labeling index and tumor diameter of lymph nodes. These results suggest that LAT1 expression is associated with disease progression in gastric carcinoma. We proposed that LAT1 could be a potential therapeutic target for gastric carcinoma cases with large lymph node metastasis.

L-amino acid transporter 1 may be a prognostic marker for local progression of prostatic cancer under expectant management.

BACKGROUND: Oncocytic L-amino acid transporter (LAT) 1 could be a target of new molecular therapy against malignancies. OBJECTIVE: To assess the correlation between overexpression of LAT1 and local progression (LP) in prostatic carcinoma (PC) patients under expectant management (EM). METHODS: This retrospective study analyzed 109 patients with PC who received EM from 1991 to 2006. The expression of LAT1, LAT2, and CD98, as well as Ki-67 labeling indices (LI), was analyzed immunohistochemically in first biopsy or TUR samples diagnosed as adenocarcinomas. RESULTS: Of the 109 patients, 44 (40%) showed LP on clinical examinations, whereas 65 showed stable disease (SD). LAT1 score and intensity were significantly higher in the LP than in the SD group, as well as among Gleason score (GS)-low (GS < 7) patients who were associated with low-risk. When the LP group was subdivided by D'Amico risk category (low-, intermediate- and high-risk groups), each showed higher LAT1 expression than the SD group. LAT1 expression did not correlate with GS or Ki-67 LI. CONCLUSIONS: Independently of GS, aberrant overexpression of LAT1 in prostatic adenocarcinoma could predict LP under EM. Although prostate biopsy samples are small, LAT1 may be a novel prognostic biomarker of LP.

Successful chemotherapy with carboplatin and nab-paclitaxel for thymic large cell neuroendocrine carcinoma: A case report.

Thymic large cell neuroendocrine carcinomas (LCNECs) are rare, and the optimal regimen for second and subsequent lines of chemotherapy for the treatment of LCNECs remains unknown. In the present case study, a 59-year-old male with post-operative recurrent thymic LCNEC was treated with nab-paclitaxel and carboplatin every 4 weeks as third-line chemotherapy, and a partial response was achieved following 4 cycles of this regimen. The patient developed grade 4 neutropenia and grade 3 leukopenia, but none of the other toxicities, including peripheral neuropathy, were severe. Therefore, the patient was able to tolerate this salvage chemotherapy. To the best of our knowledge, the present study is the first case demonstrating clinically meaningful antitumor activity by combination chemotherapy with carboplatin and nab-paclitaxel, resulting in a positive response in a patient with thymic LCNEC.

Microsatellite instability in chronic cholecystitis is indicative of an early stage in gallbladder carcinogenesis.

The study of microsatellite instability (MSI) in cases of severe chronic cholecystitis and gallbladder carcinomas, to cast light on its significance for tumorigenesis, revealed MSI in 9 (30%) of 30 cases of cholecystitis and 7 (41%) of 17 carcinomas, respectively. In addition, 5 (33%) of 15 samples of background mucosa of carcinoma were positive. Respective figures for loss of heterozygosity were 3 (10%) of 30 cases of cholecystitis, 6 (35%) of 17 carcinomas, and 1 (7%) of 15 samples of adjacent nonneoplastic mucosa. No correlation was observed among MSI state, immunohistochemical hMLH1 or hMSH2 expression, and any clinicopathologic factors. MSI was observed not only in gallbladder tumors but also in severe chronic cholecystitis and background mucosa, suggesting that it may have an important role in early-stage gallbladder carcinogenesis.

Unique and selective expression of L-amino acid transporter 1 in human tissue as well as being an aspect of oncofetal protein.

Dysregulated expression of L-type amino acid transporter 1 (LAT1), which transports large neutral amino acids, is a characteristic of various human cancers and possibly offers a molecular target for chemotherapy. LAT2, in contrast, shows lower expression in neoplasms. LAT1 is presumed to be a biomarker of many cancers, suggesting a kind of oncoprotein. However, no precise analysis of LAT1 and LAT2 expression has been performed in systemic normal tissues. To see characteristics of LAT1 and LAT2, immunohistochemical expression of LAT1 and LAT2 was assessed and compared in normal human systemic organs and tissues from 3 adults, 3 children and 3 fetuses in the present study. Cardiac muscles, hepatocytes, thymic epithelial cells and primitive neuroectodermal cells in fetus were positive with LAT1, whereas no expression was found in the respective adult tissues, indicating an aspect of oncofetal protein. In adult tissues, LAT1 was found to be expressed proximal to proliferative zones in gastrointestinal mucosa by double immunostaining of LAT1 and Ki-67. Testicular Sertoli cells, ovarian follicular cells, and pancreatic islet cells showed strong expression. Although the systemic capillary endothelium did not express LAT1, but did express LAT2, capillaries corresponding to the blood-brain, blood-follicle, and blood-retinal barriers demonstrated strong LAT1 immunoreactions. In conclusion, LAT1 was expressed in gonad tissues and several kinds of cells having special functions, as well as being discovered to be an aspect of oncofetal protein. In addition, ubiquitous LAT2 expression was confirmed immunohistochemically in systemic tissues, indicating constitutional function.