Response-guided neoadjuvant sacituzumab govitecan for localized triple-negative breast cancer: results from the NeoSTAR trial.

BACKGROUND: Sacituzumab govitecan (SG), a novel antibody-drug conjugate (ADC) targeting TROP2, is approved for pre-treated metastatic triple-negative breast cancer (mTNBC). We conducted an investigator-initiated clinical trial evaluating neoadjuvant (NA) SG (NCT04230109), and report primary results. PATIENTS AND METHODS: Participants with early-stage TNBC received NA SG for four cycles. The primary objective was to assess pathological complete response (pCR) rate in breast and lymph nodes (ypT0/isN0) to SG. Secondary objectives included overall response rate (ORR), safety, event-free survival (EFS), and predictive biomarkers. A response-guided approach was utilized, and subsequent systemic therapy decisions were at the discretion of the treating physician. RESULTS: From July 2020 to August 2021, 50 participants were enrolled (median age = 48.5 years; 13 clinical stage I disease, 26 stage II, 11 stage III). Forty-nine (98%) completed four cycles of SG. Overall, the pCR rate with SG alone was 30% [n = 15, 95% confidence interval (CI) 18% to 45%]. The ORR per RECIST V1.1 after SG alone was 64% (n = 32/50, 95% CI 77% to 98%). Higher Ki-67 and tumor-infiltrating lymphocytes (TILs) were predictive of pCR to SG (P = 0.007 for Ki-67 and 0.002 for TILs), while baseline TROP2 expression was not (P = 0.440). Common adverse events were nausea (82%), fatigue (76%), alopecia (76%), neutropenia (44%), and rash (48%). With a median follow-up time of 18.9 months (95% CI 16.3-21.9 months), the 2-year EFS for all participants was 95%. Among participants with a pCR with SG (n = 15), the 2-year EFS was 100%. CONCLUSIONS: In the first NA trial with an ADC in localized TNBC, SG demonstrated single-agent efficacy and feasibility of response-guided escalation/de-escalation. Further research on optimal duration of SG as well as NA combination strategies, including immunotherapy, are needed.

Mid-term results of Miller-Galante unicompartmental knee replacement for medial compartment knee osteoarthritis.

BACKGROUND: The purpose of this study is to analyse and report the mid-term results of 175 unicompartmental knee replacement (UKR) procedures performed for medial compartment knee arthritis from January 2001 to January 2010. MATERIALS AND METHODS: The cohort participants were selected after stringent inclusion criteria and the average follow-up was 5.6 years (range 2-10 years). The fixed-bearing UKR procedure was carried out on all patients. RESULTS: The pre-operative mean knee range of movement improved from 100° ± 11.3° to 118.3° ± 12° (p value <0.001). The pre-operative mean Knee Society (KS) knee and functional score improved from 47 ± 5.5 and 55.1 ± 4.6 to 91.8 ± 9.2 and 92 ± 10.1 (p value <0.001), respectively. The revision rate of the cohort was 4 % (seven knees) and implant survival rate was 96 % at the end of 10 years; 87 % of the cohort were satisfied with the procedure and had a normal gait pattern. In this study, there was no statistical difference between groups with a body mass index (BMI) ≤30 kg/m(2) and those with a BMI ≥30 kg/m(2), and between groups aged ≤55 years and those aged ≥55 years, in clinical and functional outcome following UKR. CONCLUSION: This study confirms that fixed-bearing UKR gives excellent results in patients with medial compartment knee arthritis who comply with the inclusion criteria. Age and BMI were not considered to influence the clinical and functional outcomes. Level of evidence-III.

Current therapeutic protocols for chronic granulomatous fungal sinusitis.

BACKGROUND: The treatment of chronic granulomatous fungal sinusitis (CGFS), a rare form of invasive fungal sinusitis, is controversial. AIM: To assess the response to postoperative antifungal therapy in patients with CGFS and suggest an effective treatment protocol. METHODOLOGY: Clinical records of patients with CGFS who had undergone excisive surgery followed by antifungal therapy were reviewed to assess current disease status. RESULTS: Fourteen male and 4 female patients were diagnosed with CGFS, based on typical histopathological and fungal smear/ culture results. Aspergillus flavus was isolated from 88.9% cases. Stage 1 patients had resectable sinonasal disease, stage 2 had additional spread to orbit/palate and stage 3 had extensive disease. Follow-up ranged from 6 months to 8 years. Residual disease was seen in all but one patient who received amphotericin B as first line therapy and in none of those who received itraconazole or voriconazole. Even those who received azoles as second line therapy were disease free at last follow-up. CONCLUSION: Surgery followed by itraconazole or voriconazole for Stage 1 and 2 disease and voriconazole for stage 3 disease is recommended for a good outcome. Amphotericin B is not recommended as first line therapy for CGFS.

The Wilms tumour gene WT1 is expressed in murine mesoderm-derived tissues and mutated in a human mesothelioma.

The tumour suppressor gene WT1 encodes a transcription factor expressed in tissues of the genito-urinary system. Inactivation of this gene is associated with the development of Wilms tumour a pediatric kidney cancer. We show that WT1 is also expressed at high levels in many supportive structures of mesodermal origin in the mouse. We also describe a case of adult human mesothelioma, a tumour derived from the peritoneal lining, that contains a homozygous point mutation within WT1. This mutation, within the putative transactivation domain, converts the protein from a transcriptional repressor of its target sequence to a transcriptional activator. The role of WT1 in normal development thus extends to diverse structures derived from embryonic mesoderm and disruption of WT1 function contributes to the onset of adult, as well as pediatric, tumours.

The EWS-WT1 translocation product induces PDGFA in desmoplastic small round-cell tumour.

Chromosomal translocations resulting in chimaeric transcription factors underlie specific malignancies, but few authentic target genes regulated by these fusion proteins have been identified. Desmoplastic small round-cell tumour (DSRT) is a multiphenotypic primitive tumour characterized by massive reactive fibrosis surrounding nests of tumour cells. The t(11;22)(p13;q12) chromosomal translocation that defines DSRT produces a chimaeric protein containing the potential transactivation domain of the Ewing-sarcoma protein (EWS) fused to zinc fingers 2-4 of the Wilms tumour suppressor and transcriptional repressor WT1 (refs 2,3). By analogy with other EWS fusion products, the EWS-WT1 chimaera may encode a transcriptional activator whose target genes overlap with those repressed by WT1 (ref. 4). To characterize its functional properties, we generated osteosarcoma cell lines with tightly regulated inducible expression of EWS-WT1. Expression of EWS-WT1 induced the expression of endogenous platelet-derived growth factor-A (PDGFA), a potent secreted mitogen and chemoattractant whose promoter contains the many potential WT1-binding sites. Native PDGFA was not regulated by wild-type WT1, indicating a difference in target gene specificity between this tumour suppressor and its oncogenic derivative. PDGFA was expressed within tumour cells in primary DSRT specimens, but it was absent in Wilms tumours expressing WT1 and Ewing sarcomas with an EWS-Fli translocation. We conclude that the oncogenic fusion of EWS to WT1 in DSRT results in the induction of PDGFA, a potent fibroblast growth factor that contributes to the characteristic reactive fibrosis associated with this unique tumour.

WT1-mediated growth suppression of Wilms tumor cells expressing a WT1 splicing variant.

A human Wilms tumor cell line (RM1) was developed to test the tumor suppressor activity of WT1, a zinc finger transcription factor that is expressed in the developing human kidney and is mutationally inactivated in a subset of Wilms tumors. Transfection of each of four wild-type WT1 isoforms suppressed the growth of RM1 cells. The endogenous WT1 transcript in these cells was devoid of exon 2 sequences, a splicing alteration that was also detected in varying amounts in all Wilms tumors tested but not in normal kidney. Production of this abnormal transcript, which encodes a functionally altered protein, may represent a distinct mechanism for inactivating WT1 in Wilms tumors.

Müllerian inhibiting substance: an instructive developmental hormone with diagnostic and possible therapeutic applications.

Dr. Alfred Jost pioneered the field of reproductive endocrinology with his seminal observation that two hormones produced by the testes are required for the male embryo to develop a normal internal reproductive tract. T induces the Wolffian ducts to differentiate into epididymides, vasa deferens, and seminal vesicles. Müllerian inhibiting substance (MIS) causes regression of the Müllerian ducts, which in its absence would normally develop into the Fallopian tubes, uterus, and upper vagina as is observed in female embryos. This review will summarize our current understanding of molecular mechanisms underlying the function of MIS both as a fetal gonadal hormone that causes Müllerian duct regression and as an adult hormone, the roles for which are currently being investigated, i.e., inhibition of steroidogenesis, germ cell development, and cancer. We will also address the regulation of MIS expression as one of the first genes expressed after the commitment of the bipotential gonads to differentiate into testes under the influence of SRY, the gene on the sex-determining region of the Y chromosome. We will discuss what is known regarding MIS signal transduction, which as with other members of the TGFbeta family of growth and differentiation factors, occurs through a heteromeric complex of single transmembrane serine/threonine kinase receptors to effect downstream signaling events, including Smad, nuclear factor-kappaB, beta-catenin, and p16 activation. Finally, we will assess the clinical relevance of studying MIS in patients with persistent Müllerian duct syndrome and our efforts to determine the therapeutic value of MIS for patients with ovarian and other MIS receptor-expressing cancers.

Application of the 4-trifluoromethylbenzenepropargyl ether group as an unhindered, electron deficient protecting group for stereoselective glycosylation.

4-Trifluoromethylbenzenepropargyl ethers are stable and sterically minimal alcohol protecting groups that are readily cleaved in a single step by exposure to lithium naphthalenide. In conjunction with the 4,6-O-benzylidene protecting group, glycosylation reactions of 2-O-(4-trifluoromethylbenzenepropargyl)-protected mannosyl donors are extremely beta-selective.

Intracellular association of the protein product of the c-myc oncogene with the TATA-binding protein.

The c-myc proto-oncogene encodes nuclear phosphoproteins that bind DNA in a sequence-specific fashion and appear to function as transcriptional activators. Here we demonstrate that a 40-kDa nuclear protein coimmunoprecipitated with c-Myc specifically when nuclear proteins, extracted from nuclei of exponentially growing murine B-lymphoma WEHI 231 cells by using procedures for preparation of trans-acting factors, were reacted with anti-c-Myc antibodies made against different regions of the c-Myc protein. In contrast, preparation of nuclear lysates under denaturing conditions significantly reduced this coprecipitation. Upon incubation of WEHI 231 cells with the reversible chemical cross-linking agent dithiobis(succinimidyl propionate), the 40-kDa protein could be cross-linked to c-Myc protein intracellularly. Identification of the 40-kDa protein as the TATA-binding protein (TBP) of the TFIID transcription initiation complex was made by comigration and V-8 protease mapping, which yielded identical peptide fragments upon digestion of the 40-kDa protein and material immunoprecipitated with an anti-TBP specific antibody. Furthermore, in vitro-translated TBP bound to the amino-terminal portion of c-Myc. Column chromatography of cross-linked nuclear proteins showed TBP to be in a large-molecular-weight complex with c-Myc, consistent with a transcription initiation complex. These results indicate that intracellularly, c-Myc interacts with TBP, suggesting a mechanism of interaction of this oncoprotein with the basal transcription machinery.

Induction of p21 by the Wilms' tumor suppressor gene WT1.

WT1 encodes a zinc finger transcription factor that is expressed in the developing kidney and the inactivation of which leads to Wilms' tumor, a pediatric kidney cancer. We have recently shown that inducible expression of WT1 in osteosarcoma cells triggers programmed cell death, an effect that is associated with transcriptional repression of the endogenous epidermal growth factor receptor. We now show that WT1-mediated apoptosis is preceded by induction of the cyclin-dependent kinase inhibitor p21, associated with G1 phase arrest. This effect is only demonstrated by WT1 isoforms with an intact DNA binding domain, and it is associated with increased expression of endogenous p21 mRNA. WT1-mediated induction of p21 is independent of p53, another tumor suppressor gene known to regulate p21 expression. In the kidney, p21 is expressed in differentiating glomerular podocytes along with WT1. We conclude that induction of p21 expression may contribute to WT1-dependent differentiation pathways in the kidney and potentially to the function of WT1 as a tumor suppressor gene.

Changes in phosphorylation of myc oncogene and RB antioncogene protein products during growth arrest of the murine lymphoma WEHI 231 cell line.

The expression of the protein products of the c-myc oncogene and retinoblastoma susceptibility gene (RB) was investigated during either goat anti-mouse immunoglobulin (GaMIg)- or phorbol ester (TPA)-induced growth arrest of the murine B-lymphoma cell line WEHI 231. Previously we have demonstrated that c-myc mRNA levels increase within 1-2 h of treatment, return to control levels by 4 h, and decline below these values by 24 h of treatment. Here we demonstrate that the level of c-myc protein synthesis and mRNA change in parallel. The predominant c-myc protein expressed during the time course is the one initiated at the AUG codon (P2). The myc protein synthesized following 1-2 h of anti-immunoglobulin or TPA treatment migrates more slowly in a polyacrylamide gel as a result of increased phosphorylation. This hyperphosphorylation was no longer detectable by 4-6 h of treatment. Furthermore, the hyperphosphorylated myc protein appears to be more readily extractable with salt than the hypophosphorylated form. The product of the RB gene is present in multiple phosphorylation states in exponentially growing WEHI 231 cells. By 8 h of GaMIg or TPA treatment, a hypophosphorylated form begins to be detectable and significant levels were seen by 15 h. Thus post-translational control of both c-myc and RB expression occurs during the growth arrest of WEHI 231 cells. These changes in phosphorylation may play a role in mediating the cessation of proliferation of these cells.

E1B 55K sequesters WT1 along with p53 within a cytoplasmic body in adenovirus-transformed kidney cells.

WT1 encodes a tumor suppressor that is expressed in cells of the developing kidney and is inactivated in Wilms tumor, a pediatric kidney cancer. The adenovirus E1B 55K gene product contributes to the transformation of primary baby rat kidney (BRK) cells by binding and inactivating the product of the p53 tumor suppressor. We have previously demonstrated that WT1 and p53 are present within a protein complex in vivo. We now show that WT1 is physically associated with E1B 55K in adenovirus-transformed cells, an interaction that is mediated by the first two zinc fingers of WT1. Immunodepletion of p53 abrogates the coimmunoprecipitation of E1B 55K and WT1, consistent with the presence of a trimeric protein complex containing these three proteins. In the presence of E1B 55K, WT1 which is normally localized in the nucleus, is retained within a very high molecular weight complex and sequestered in the characteristic perinuclear cytoplasmic body that contains E1B 55K and p53. Expression of E1B 55K in osteosarcoma cells that undergo apoptosis following expression of WT1 inhibits WT1-mediated cell death. We conclude that E1B 55K may target WT1 along with p53, resulting in the functional inactivation of both tumor suppressor gene products by this viral oncoprotein.

BRCA1 and GADD45 mediated G2/M cell cycle arrest in response to antimicrotubule agents.

BRCA1 is a tumour suppressor gene implicated in the predisposition to early onset breast and ovarian cancer. We have generated cell lines with inducible expression of BRCA1 to evaluate its role in mediating the cellular response to various chemotherapeutic drugs commonly used in the treatment of breast and ovarian cancer. Induction of BRCA1 in the presence of Taxol and Vincristine resulted in a dramatic increase in cell death; an effect that was preceded by an acute arrest at the G2/M phase of the cell cycle and which correlated with BRCA1 mediated induction of GADD45. A proportion of the arrested cells were blocked in mitosis suggesting activation of both a G2 and a mitotic spindle checkpoint. In contrast, no specific interaction was observed between BRCA1 induction and treatment of cells with a range of DNA damaging agents including Cisplatin and Adriamycin. Inducible expression of GADD45 in the presence of Taxol induced both G2 and mitotic arrest in these cells consistent with a role for GADD45 in contributing to these effects. Our results support a role for both BRCA1 and GADD45 in selectively regulating a G2/M checkpoint in response to antimicrotubule agents and raise the possibility that their expression levels in cells may contribute to the toxicity observed with these compounds.

Human ovarian cancer, cell lines, and primary ascites cells express the human Mullerian inhibiting substance (MIS) type II receptor, bind, and are responsive to MIS.

Six human ovarian cancer cell lines and samples of ascites cells isolated from 27 patients with stage III or IV ovarian papillary serous cystadenocarcinoma were studied individually to test whether recombinant human Mullerian inhibiting substance (rhMIS) acts via its receptor. To do these experiments, we scaled up production of rhMIS and labeled it successfully with biotin for binding studies, cloned the human MIS type II receptor for mRNA detection, and raised antibodies to an extracellular domain peptide for protein detection. These probes were first tested on the human ovarian cancer cell lines and then applied to primary ovarian ascites cells. rhMIS inhibited colony growth of five of six cell lines that expressed the human MIS type II receptor mRNA by Northern analysis while not inhibiting receptor-negative COS cells. Flow cytometry performed on MIS-sensitive ovarian cancer cell lines demonstrated specific and saturable binding of rhMIS (Kd = 10.2 nM). Ascites cells from 15 of 27 or 56% of patients tested bound biotinylated MIS (MIS-biotin) and, of the 11 that grew in soft agarose, 9 of 11 or 82% showed statistically significant inhibition of colony formation. Of the 15 patients who bound biotinylated MIS, mRNA was available for analysis from 9, and 8 of 9 expressed MIS type II receptor mRNA by reverse transcription-PCR, showing a statistically significant correlation, compared with binding, by chi2 analysis (P = 0.025). Solid ovarian cancers were positive for the MIS type II receptor protein by immunohistochemical staining, which colocalized with staining for antibody to CA-125 (OC-125). Thus, the detection of the MIS type I receptor by flow cytometry may be a useful predictor of therapeutic response to MIS and may be a modality to rapidly choose patients with late-stage ovarian cancer for treatment with MIS.

Transforming Growth Factor-beta superfamily: evaluation as breast cancer biomarkers and preventive agents.

The Transforming Growth Factor-beta (TGFbeta) superfamily of cytokines is comprised of a number of structurally-related, secreted polypeptides that regulate a multitude of cellular processes including proliferation, differentiation and neoplastic transformation. These growth regulatory molecules induce ligand-mediated hetero-oligomerization of distinct type II and type I serine/threonine kinase receptors that transmit signals predominantly through receptor-activated Smad proteins but also induce Smad-independent pathways. Ligands, receptors and intracellular mediators of signaling initiated by members of the TGFbeta family are expressed in the mammary gland and disruption of these pathways may contribute to the development and progression of human breast cancer. Since many facets of TGFbeta and breast cancer have been recently reviewed in several articles, except for discussion of recent developments on some aspects of TGFbeta, the major focus of this review will be on the role of activins, inhibins, BMPs, nodal and MIS-signaling in breast cancer with emphasis on their utility as potential diagnostic, prognostic and therapeutic targets.

Patellar clunk syndrome in patellofemoral arthroplasty--a case report.

Patellar clunk syndrome is characterised by the formation of a fibrous nodule at the articular side of junction of superior pole of patella and the quadriceps tendon. Until now, it is only described in posterior cruciate substituting total knee replacements. We report the patellar clunk syndrome in a lady with patellofemoral joint replacement.

Relative etiological importance of adenoid hypertrophy versus sinusitis in children with persistent rhinorrhoea.

Persistent rhinorrhoea is a common, yet often neglected, problem among Indian children. This study was designed to evaluate the relative etiological importance of adenoid hypertrophy versus sinusitis in children with persistent rhinorrhea. Additionally, the association between S. pneumoniae colonization and adenoid hypertrophy was studied. Children aged 1-14 years with persistent rhinorrhea underwent clinical evaluation, rigid nasal endoscopy and xrays of the nasopharynx and paranasal sinuses to ascertain the presence of adenoid hypertrophy and sinusitis using standard criteria. Nasopharyngeal swabbing to ascertain the presence of nasopharyngeal colonization with S. pneumoniae was also performed. Adenoid hypertrophy was more consistently associated with persistent rhinorrhea than sinusitis (p < 0.0001). Coincident adenoid hypertrophy and sinusitis occurred in 57 %. S. pneumoniae was cultured in only 29 % of children. Up to 47 % of patients had features of nasal allergy. There was no association between S. pneumoniae colonization and adenoid hypertrophy (p = 0.1). Adenoid hypertrophy is an important cause of persistent rhinorrhea in children. Measures to evaluate for and treat adenoid hypertrophy should be instituted early to alleviate the problem of persistent rhinorrhoea in children. S. pneumoniae colonization of the nasopharynx is not a major etiological factor for persistent rhinorrhoea in these children. Nasal allergy may be a cause of adenoid hypertrophy in roughly half the children.

Synthesis, spectra, dioxygen affinity and antifungal activity of Ru(III) Schiff base complexes.

The reaction of ruthenium(III) complexes, [RuX(3)(EPh(3))(3)] (E=As, X=Cl or Br; E=P, X=Cl) and [RuBr(3)(PPh(3))(2)(CH(3)OH)] with bidendate Schiff base ligands derived by condensing salicylaldehyde with methylamine (Hsalmet), cyclohexylamine (Hsalchx), 2-aminopyridine (Hsalampy) have been carried out. The complexes were characterized by analytical and spectral studies (IR, electronic and EPR) and are formulated as [RuX(EPh(3))(LL')(2)] (where LL'=monobasic bidentate Schiff base ligand; E=P or As, X=Cl or Br). An octahedral geometry has been tentatively proposed for the new complexes. Dioxygen affinity of some of the Ru(III) Schiff base complexes was studied by cyclic voltammetry. The representative Schiff bases and their complexes were tested in vitro to evaluate their activity against fungi, namely, Aspergillus flavus (A. flavus) and Fusarium species.

Measurement of Pasteurella haemolytica-specific lung and serum antibodies by ELISA.

The modified enzyme-linked immunosorbent assay (ELISA) was used to determine the relative quantities of class-specific antibodies to Pasteurella haemolytica. IgG1, IgG2 and IgA were present in significantly higher quantities in bronchoalveolar washings (BAW), but in decreasing quantities, respectively; IgM was present in very low amounts. IgM, IgG1 and IgG2 were present in serum, again in decreasing quantities, respectively. IgA antibody quantities were lowest in serum. The indirect antibody ELISA was found to be superior to the indirect bacterial agglutination (IBA) technique for determining antibody titres against P. haemolytica.

Colorimetric assay using XTT for assessing virulence of avian Pasteurella multocida strains.

A colorimetric assay using sodium 3,3'-[1[(phenylamino)carbonyl]3,4- tetrazolium]-bis(4-methoxy-6-nitro) benzene sulfonic acid hydrate (XTT) was adapted to quantitate bactericidal activity of chicken macrophage HD 11 cell line against five Pasteurella multocida strains and an avirulent transposon insertion mutant. The strains used were virulent P1059, and D92, and four avirulent strains including a streptomycin resistant mutant of P1059 (P1059 SmR), two live vaccine strains namely, the Clemson University (CU) and M9, and a transposon insertion mutant PmTn-294. Percentage of bacteria killed by chicken macrophage (HD 11) cells was determined by extrapolation from a standard formazan curve derived by incubating XTT with known bacterial cell numbers of each strain. The amount of formazan as measured by absorption at 450 nm was directly related to the number of viable bacterial cells. The percentages of P1059 SmR, CU, M9 and PmTn-294 killed by HD 11 cells were approximately 50%, 61%, 25% and 34%, respectively. By contrast, the virulent P1059 and D92 strains were resistant to killing, and were able to replicate inside the HD 11 cells. Association of virulence with resistance to phagocytic killing by HD 11 cells as assessed by the colorimetric bactericidal assay, was validated with resistance to complement (C')-mediated killing and a turkey mortality test. Strains P1059 and D92 were resistant to C'-mediated killing, whereas strains P1059 SmR, CU, M9 and PmTn-294 strains were susceptible. All turkeys challenged with P1059 or D92 were dead within 18 hrs. Mortality did not occur in turkeys challenged with strains of P1059 SmR, M9 and PmTn-294. The mortality among CU challenged turkeys ranged from 0 to 40%. The results suggest that the colorimetric bactericidal assay using XTT can be used to quantitate chicken macrophage phagocytic killing of P. multocida strains, and may be a valuable assay to differentiate virulent from avirulent strains of avian P. multocida.