Immune checkpoint inhibitors for POLE or POLD1 proofreading-deficient metastatic colorectal cancer.

BACKGROUND: POLE and POLD1 proofreading deficiency (POLE/D1pd) define a rare subtype of ultramutated metastatic colorectal cancer (mCRC; over 100 mut/Mb). Disease-specific data about the activity and efficacy of immune checkpoint inhibitors (ICIs) in POLE/D1pd mCRC are lacking and it is unknown whether outcomes may be different from mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H) mCRCs treated with ICIs. PATIENTS AND METHODS: In this global study, we collected 27 patients with mCRC harboring POLE/D1 mutations leading to proofreading deficiency and treated with anti-programmed cell death-ligand 1 alone +/- anti-cytotoxic T-lymphocyte antigen-4 agents. We collected clinicopathological and genomic characteristics, response, and survival outcomes after ICIs of POLE/D1pd mCRC and compared them with a cohort of 610 dMMR/MSI-H mCRC patients treated with ICIs. Further genomic analyses were carried out in an independent cohort of 7241 CRCs to define POLE and POLD1pd molecular profiles and mutational signatures. RESULTS: POLE/D1pd was associated with younger age, male sex, fewer RAS/BRAF driver mutations, and predominance of right-sided colon cancers. Patients with POLE/D1pd mCRC showed a significantly higher overall response rate (ORR) compared to dMMR/MSI-H mCRC (89% versus 54%; P = 0.01). After a median follow-up of 24.9 months (interquartile range: 11.3-43.0 months), patients with POLE/D1pd showed a significantly superior progression-free survival (PFS) compared to dMMR/MSI-H mCRC [hazard ratio (HR) = 0.24, 95% confidence interval (CI) 0.08-0.74, P = 0.01] and superior overall survival (OS) (HR = 0.38, 95% CI 0.12-1.18, P = 0.09). In multivariable analyses including the type of DNA repair defect, POLE/D1pd was associated with significantly improved PFS (HR = 0.17, 95% CI 0.04-0.69, P = 0.013) and OS (HR = 0.24, 95% CI 0.06-0.98, P = 0.047). Molecular profiling showed that POLE/D1pd tumors have higher tumor mutational burden (TMB). Responses were observed in both subtypes and were associated with the intensity of POLE/D1pd signature. CONCLUSIONS: Patients with POLE/D1pd mCRC showed more favorable outcomes compared to dMMR/MSI-H mCRC to treatment with ICIs in terms of tumor response and survival.

HPV-positive clinically advanced squamous cell carcinoma of the urinary bladder (aBSCC): A comprehensive genomic profiling (CGP) study.

BACKGROUND: Advanced bladder squamous cell carcinoma (aBSCC) is an uncommon form of urinary bladder malignancy when compared with the much higher urothelial carcinoma incidence. We studied the genomic alteration (GA) landscape in a series of aBSCC based on the association with human papilloma virus (HPV) to determine if differences in GA would be observed between the positive and negative groups. METHODS: Using a hybrid capture-based FDA-approved CGP assay, a series of 171 aBSCC were sequenced to evaluate all classes of GA. Tumor mutational burden (TMB) was determined on up to 1.1 Mbp of sequenced DNA and microsatellite instability (MSI) was determined on up to 114 loci. Programmed cell death ligand -1 (PD-L1) expression was determined by IHC (Dako 22C3) with negative expression when PD-L1 was 0, lower expression of positivity set at 1 to 49%, and higher expression set at ≥50% expression. RESULTS: Overall, 11 (6.4%) of the aBSCC were found to harbor HPV sequences (10 HPV16 and 1 HPV 11). HPV+ status was identified slightly more often in women (NS) and in younger patients (P = 0.04); 2 female patients with aBSCC had a prior history of SCC including 1 anal SCC and 1 vaginal SCC. HPV+ aBSCC had fewer GA/tumor (P < 0.0001), more inactivating mutations in RB1 (P = 0.032), and fewer inactivating GA in CDKN2A (P < 0.0001), CDKN2B (P = 0.05), TERT promoter (P = 0.0004) and TP53 (P < 0.0001). GA in genes associated with urothelial carcinoma including FGFR2 and FGFR3 were similar in both HPV+ and HPV- aBSCC groups. MTAP loss (homozygous deletion) which has emerged as a biomarker for PRMT5 inhibitor-based clinical trials was not identified in any of the 11 HPV+ aBSCC cases, which was significantly lower than the 28% positive frequency of MTAP loss in the HPV- aBSCC group (P < 0.0001). MTOR and PIK3CA pathway GA were not significantly different in the 2 groups. Putative biomarkers associated with immunotherapy (IO) response, including MSI and TMB status, were also similar in the 2 groups. PD-L1 expression data was available for a subset of both HPV+ and HPV- cases and showed high frequencies of positive staining which was not different in the 2 groups. CONCLUSIONS: HPV+ aBSCC tends to occur more often in younger patients. As reported in other HPV-associated squamous cell carcinomas, HPV+ aBSCC demonstrates significantly reduced frequencies of inactivating mutations in cell cycle regulatory genes with similar GA in MTOR and PIK3CA pathways. The implication of HPV in the pathogenesis of bladder cancer remains unknown but warrants further exploration and clinical validation.

Clinical Pharmacogenetics Implementation Consortium (CPIC) Guidelines for CYP3A5 Genotype and Tacrolimus Dosing.

Tacrolimus is the mainstay immunosuppressant drug used after solid organ and hematopoietic stem cell transplantation. Individuals who express CYP3A5 (extensive and intermediate metabolizers) generally have decreased dose-adjusted trough concentrations of tacrolimus as compared with those who are CYP3A5 nonexpressers (poor metabolizers), possibly delaying achievement of target blood concentrations. We summarize evidence from the published literature supporting this association and provide dosing recommendations for tacrolimus based on CYP3A5 genotype when known (updates at www.pharmgkb.org).

"Nuclear FGF receptor-1 and CREB binding protein: an integrative signaling module".

In this review we summarize the current understanding of a novel integrative function of Fibroblast Growth Factor Receptor-1 (FGFR1) and its partner CREB Binding Protein (CBP) acting as a nuclear regulatory complex. Nuclear FGFR1 and CBP interact with and regulate numerous genes on various chromosomes. FGFR1 dynamic oscillatory interactions with chromatin and with specific genes, underwrites gene regulation mediated by diverse developmental signals. Integrative Nuclear FGFR1 Signaling (INFS) effects the differentiation of stem cells and neural progenitor cells via the gene-controlling Feed-Forward-And-Gate mechanism. Nuclear accumulation of FGFR1 occurs in numerous cell types and disruption of INFS may play an important role in developmental disorders such as schizophrenia, and in metastatic diseases such as cancer. Enhancement of INFS may be used to coordinate the gene regulation needed to activate cell differentiation for regenerative purposes or to provide interruption of cancer stem cell proliferation.

Effect of brimonidine tartrate ophthalmic solution 0.2% on pupil size in normal eyes under different luminance conditions.

PURPOSE: To evaluate the effect of brimonidine tartrate ophthalmic solution 0.2% (Alphagan) on pupil size in normal eyes. Three luminance conditions were used to assess the potential use of brimonidine in postoperative refractive patients who experience nighttime vision problems related to large pupil size. SETTING: McDonald Eye Associates, Fayetteville, Arkansas, USA. METHODS: Pupil size was measured in 16 eyes of 16 participants with the Colvard pupillometer under 3 luminance conditions. One drop of brimonidine 0.2% was administered to each patient. Pupil size was then measured using the same technique 30 minutes and 4 and 6 hours after drop administration. RESULTS: Under scotopic conditions, 100% of the pupils showed significant miosis at 30 minutes (P <.05). The effect continued in all eyes for 4 hours. At 6 hours, a miotic effect was still present in 81.3%. However, under photopic luminance, there was no significant effect on pupil size in all 16 eyes (P >.05). The pupil size in 5 eyes (31.2%) was not affected at 30 minutes or 4 or 6 hours. At 6 hours, 15 eyes (93.8%) had returned to their preinstillation size. CONCLUSION: Brimonidine tartrate 0.2% had a significant effect in decreasing pupil size under scotopic conditions. The results indicate that the drug can decrease night-vision difficulties such as halos, star bursts, glare, and monocular diplopia in postoperative refractive patients.

Alterations of glycosaminoglycans during patellar tendon autograft healing after posterior cruciate ligament replacement. A biochemical study in a sheep model.

In each of 30 skeletally mature sheep, the posterior cruciate ligament was replaced in one knee by a free patellar tendon autograft using the central third of the ipsilateral patellar tendon. The healing autograft was compared with the contralateral posterior cruciate ligament and the patellar tendons and posterior cruciate ligaments of nonoperated animals. The content of glycosaminoglycans, chondroitin sulfate disaccharides, and dermatan sulfate disaccharides was assessed biochemically at six periods during the 2 years after surgery. The total glycosaminoglycans and chondroitin sulfate disaccharides in the native posterior cruciate ligament was threefold that in the native patellar tendon. In contrast, the amount of dermatan sulfate disaccharides was similar in both the native tendon and native ligament. In the autograft, glycosaminoglycans and chondroitin sulfate disaccharides increased significantly to about 144% and 172%, respectively, of the contralateral posterior cruciate ligament at Week 104. The dermatan sulfate disaccharides in the autograft also showed a significant increase up to Week 26, followed by a remarkable but not significant decrease until the end of the study. In the contralateral posterior cruciate ligament, the dermatan sulfate disaccharides increased significantly between Weeks 52 and 104. Thus, the amount of dermatan sulfate disaccharides was similar in both the autograft and the contralateral posterior cruciate ligament after 2 years. This study suggests that the patellar tendon autograft did not completely assume the biochemical properties of the posterior cruciate ligament.

[Morphologic aspects of alloplastic augmentation in replacement of the posterior cruciate ligament. An experimental study on the sheep]. / Morphologische Aspekte der alloplastischen Augmentation beim Ersatz des hinteren Kreuzbandes. Eine experimentelle Studie am Schaf.

The treatment of injuries to the posterior cruciate ligament (PCL) remains controversial. Various problems have prevented PCL reconstruction from consistently producing the knee stability desired. Biological graft tissue undergoes a remarkable healing process comprising different phases. The strength of autogenous graft material decreases soon after the operation. During this early healing phase synthetic augmentation could protect the graft tissue from overloading or overstretching, supporting the tissue restoration process. In order to evaluate the morphological effects of the ligament augmentation device (LAD) on a free patellar tendon autograft in PCL reconstruction a comparative study in sheep was conducted. In 24 mature sheep the PCL was replaced with either a patellar tendon autograft alone or a patellar tendon autograft augmented by the LAD. The LAD was fixed at both ends. The animals were not immobilized after the operation. Tibial fixation was released 8 weeks after the operation. The autografts of both groups were histologically evaluated after 2, 6, 16, 26, 52 and 104 weeks. In addition to necrotic and degenerative alterations a pronounced inflammatory reaction could be seen in the LAD-augmented autografts soon after the operation. Compared with the non-augmented autograft, tissue formation and remodeling was delayed in the augmented group. After 1 and 2 years, the morphology of the autograft tissue was similar in the augmented and the non-augmented group and was different from that of a normal PCL. The LAD was surrounded by a chronic inflammatory reaction, and collagen fiber ingrowth into the LAD was not observed. Transmission electron microscopy showed that small-diameter collagen fibrils were predominant in the graft tissue of both groups. Thus, better remodeling of the autograft tissue in the presence of the LAD was not demonstrable in this particular study. The value of synthetic augmentation of biological grafts of PCL reconstruction seems to be questionable at present.

The morphological effects of synthetic augmentation in posterior cruciate ligament reconstruction: an experimental study in a sheep model.

The treatment of posterior cruciate ligament (PCL) injuries remains controversial. Due to various problems, PCL reconstruction has not consistently produced the knee stability desired. Biological graft tissue undergoes a remarkable healing process comprising different phases. The strength of autogenous graft material decreases soon after operation. During this early healing phase synthetic augmentation could protect the graft tissue from overloading or overstretching, supporting the tissue revitalization and remodeling process. In order to evaluate the morphological effects of the ligament augmentation device (LAD) on a free patellar tendon autograft in PCL reconstruction, a comparative study in sheep was conducted. In 24 mature sheep, the PCL was replaced with either a patellar tendon autograft alone or a patellar tendon autograft augmented by the LAD. The LAD was fixed at both ends. After the operation the animals were not immobilized. Tibial fixation was released 8 weeks postoperation. The autografts of both groups were histologically evaluated after 2, 6, 16, 26, 52, and 104 weeks. In addition to necrotic and degenerative alterations, a remarkable inflammatory reaction could be seen in the LAD-augmented autografts early postoperation. Compared with the nonaugmented autografts, tissue formation and remodeling were delayed in the augmented group. After 1 and 2 years, the morphology of the autograft tissue was similar in both the augmented and nonaugmented group and differed from that of a normal PCL. The LAD was surrounded by a chronic inflammatory reaction, and collagen fiber ingrowth into the LAD was not observed. Using transmission electron microscopy, small diameter collagen fibrils were predominant in the graft tissue of both groups. Thus, a better remodeling of the autograft tissue in the presence of the LAD could not be demonstrated in this particular study. The value of synthetic augmentation of biological grafts in PCL reconstruction seems to be questionable at present.

Relationships between endothelial cells, pericytes, and osteoblasts during bone formation in the sheep femur following implantation of tricalciumphosphate-ceramic.

BACKGROUND: The origin of osteoblasts is still controversial. Whereas several authors consider the stromal fibroblast of the bone marrow as the osteoprogenitor cell, others propose that the osteoblasts can be derived from the "capillary system." The present study examines the replacement of tricalciumphosphate (TCP)-ceramic implanted into an artificial bone defect by newly formed bone. The results support the hypothesis that osteogenic cells can be derived from invading blood vessels. METHODS: The spongiosa of the trochanter major of sheep was removed and the defect was filled with TCP-ceramic. Two months after surgery the ceramic implants together with the surrounding bone were removed and processed for transmission electron microscopy. Serial ultrathin sections of three newly formed osteons were examined. RESULTS: The osteons contain one or two small sprouting capillaries, a peripheral layer of osteoblasts, and in between, a network of glycogen-rich cells. Some of the glycogen-rich cells are completely or partly surrounded by the endothelial basal lamina and are thereby characterized as pericytes. Weibel-Palade bodies, which are considered to be a marker of endothelial cells, were occasionally observed in glycogen-rich pericytes. CONCLUSIONS: Since pericytes differentiate into osteoblasts under in vivo and in vitro conditions, and have thus been regarded as osteoprogenitor cells, the presence of Weibel-Palade bodies in these cells suggest that osteogenic cells can be derived from endothelial cells.

Collagen fibril organization in the patellar tendon autograft after posterior cruciate ligament reconstruction. A quantitative evaluation in a sheep model.

We replaced the posterior cruciate ligament in 30 skeletally mature sheep with a patellar tendon autograft using the central third of the ipsilateral patellar tendon. The healing autograft was compared with the contralateral posterior cruciate ligament and the patellar tendons and posterior cruciate ligaments of nonoperated animals. The collagen fibril diameters were analyzed using transmission electron photomicrographs of fibril cross sections taken at six periods during the 2 years after surgery. The patellar tendon and posterior cruciate ligament were characterized by a broad, nongaussian distribution of collagen fibril diameters. The autografts shifted to a unimodal distribution by an increase of small-diameter collagen fibrils. The frequency of small-diameter fibrils measuring up to 100 nm was 99% after 2 years. At that time, these small-diameter fibrils represented 91.6% of the area covered by collagen fibrils. The mean diameter of the collagen fibrils in the autografts significantly decreased to 45% of the controls at Week 26 and remained at this level until the end of this study. The percentage of area covered by collagen fibrils per 1 micron 2 was 78% of the controls 2 years post-operatively. This study suggests that the patellar tendon autograft could not reproduce the collagen fibril organization of the posterior cruciate ligament. This may be a biologic factor responsible for inconsistent results in posterior cruciate ligament replacement.

Ultrastructural changes of the patellar tendon as a cruciate ligament substitute (one year and two year results).

In four black-faced sheep, the posterior cruciate ligament was replaced with a free autogenous patellar tendon transplant. Tissue samples from the transplants were investigated by light and electron microscopy 1 year and 2 years after surgery. The normal contralateral posterior cruciate ligament and the normal contralateral patellar tendon were used as controls. The structural differences concerned cells, collagen fibrils, elastic tissue and proteoglycans. Most of the cells of the contralateral patellar tendon were spindle-shaped, whereas those of the transplant were frequently chondroid. In the central region of the transplant as well as in the area far from the bone, cell degenerations, and occasionally hypo- or even acellular zones were found. Measurements of the diameter of collagen fibrils in both contralateral patellar tendon and posterior cruciate ligament showed a more or less pronounced bimodal distribution. A unimodal distribution with mainly thin fibrils (20-60 nm) was demonstrated in the transplant tissue which also revealed some morphological alterations of the collagen fibrils. Thin elastic fibers (microfibrils and amorphous material) were randomly scattered among the collagen fibrils of the control samples, bundles of microfibrils (without amorphous material) characterized the transplant. Staining with Alcian blue in the presence of 0.3 M MgCl2 demonstrated a close relationship between proteoglycans and collagen fibrils as well as elastic components in patellar tendon. This arrangement was lost in the transplant where abundant proteoglycans were revealed which, however, composed a tight irregular network between the collagen fibrils. The results serve as a baseline for understanding the impaired biochemical properties of a free autogenous patellar tendon transplant.

Efficacy of a minimal contact version of a multimodal smoking cessation program.

A five-week multimodal smoking cessation program was delivered in two formats: Weekly Contact Group meetings led by graduate student leaders versus a minimal contact By-Mail version consisting of weekly mailings of program materials. By-Mail subjects also had access to a "hotline" number they could call with questions and problems. Of 43 smokers who began the Contact Group program, 37% were abstinent at one-year follow-ups; 41% of the 49 By-Mail subjects were abstinent at one year. These results suggest that cost effective minimal contact cessation programs can benefit the many smokers who are unwilling or unable to visit cessation clinics.

Biological aspects of long-term failure of autografts after cruciate ligament replacement.

The alterations of the ultrastructure of the posterior cruciate ligament autograft of patellar tendon origin were examined in a sheep model 1 year after surgery. The ultrastructure was also compared with that of the normal contralateral posterior cruciate ligament and patellar tendon. The most striking finding was the unimodal distribution of the collagen fibrils, with a predominance of loosely packed thin fibrils in the central portion of the autograft. The results suggested that the remodeled autograft tissue became highly organized but never exhibited the ultrastructural features of a ligament. This could be responsible for the decreased biomechanical properties and the long-term failure of a patellar tendon autograft.

[Morphological results after an experimental transplantation of autogenous cancellous bone in dogs (author's transl)]. / Morphologisch-experimenteller Beitrag zur Kenntnis der Vorgänge bei der Verpflanzung von autologer Beckenkammspongiosa bei Hunden

Cell activity during the period of healing of an autogenous cancellous graft inserted into an artificial continuity defect of the ulna was studied in 20 adult dogs by light microscopy using the semithin sectioning technique. The defects were stabilised by osteosynthesis using metal plates and screws. The animals were divided into 4 groups and the autografts were investigated 1, 2, 4 and 8 weeks after transplantation. Histologic analysis showed, that ... 1. one week after transplantation, undifferentiated cells resembling reticular cells, haemocytoblasts and many closely packed osteoblasts were scattered among the trabecular network of the autogenous cancellous graft. The survival of transplanted cells in our opinion is evident, by the absence of any sign of cell death or macrophage activity. 2. two to 4 weeks after transplantation a remarkable increase of the osteoblast activity was noted. This osteogenic cell activity was mainly directed toward bone formation along the surface of contact of the autograft with the adjoining bone and there was more than one layer of osteoblasts and osteoid. Osteoblasts were also found lying along the trabecular surface of transplanted cancellous bone, but here they were arranged in a layer, which was usually only one cell deep. 3. eight weeks after transplantation there was a remarkable change in the appearance of the autogenous cancellous graft. The activity of the multinucleated osteoclasts was significantly increased in the direction of the surface of contact of the autograft with the compact receptor bone. Evidently the osteoclasts produce the prior conditions for a closer contact of the autogenous cancellous graft with the adjoining compact bone.