Targeting the microenvironment in solid tumors

Tumorigenesis is a complex and dynamic process involving different cellular and non-cellular elements composed of tumor microenvironment (TME). The interaction of TME with cancer cells is responsible for tumor development, progression and drug resistance. TME consists of non malignant cells of the tumor such as cancer associated fibroblasts (CAFs), endothelial cells and pericytes composing tumor vasculature, immune and inflammatory cells, bone marrow derived cells, and the extracellular matrix (ECM) establishing a complex cross-talk with tumor. These interactions contribute towards proliferation and invasion of the tumor by producing growth factors, chemokines and matrix-degrading enzymes. ECM is a complex system containing macromolecules with distinctive physical, biochemical and biomechanical properties. During tumorigenesis this system is deregulated favoring the generation of tumorigenic microenvironment enhancing tumor-associated angiogenesis and inflammation. An important step of anticancer treatment is the identification of the biological alterations present in TME in order to target these key molecular players. Multitargeted approaches, providing a simultaneous inhibition of TME components, may offer a more efficient way to treat cancer. In this manuscript we overview the function of each components of TME and the treatments targeting the key players.

ICAM1 initiates CTC cluster formation and trans-endothelial migration in lung metastasis of breast cancer

Circulating tumor cell (CTC) clusters mediate metastasis at a higher efficiency and are associated with lower overall survival in breast cancer compared to single cells. Combining single-cell RNA sequencing and protein analyses, here we report the profiles of primary tumor cells and lung metastases of triple-negative breast cancer (TNBC). ICAM1 expression increases by 200-fold in the lung metastases of three TNBC patient-derived xenografts (PDXs). Depletion of ICAM1 abrogates lung colonization of TNBC cells by inhibiting homotypic tumor cell-tumor cell cluster formation. Machine learning-based algorithms and mutagenesis analyses identify ICAM1 regions responsible for homophilic ICAM1-ICAM1 interactions, thereby directing homotypic tumor cell clustering, as well as heterotypic tumor-endothelial adhesion for trans-endothelial migration. Moreover, ICAM1 promotes metastasis by activating cellular pathways related to cell cycle and stemness. Finally, blocking ICAM1 interactions significantly inhibits CTC cluster formation, tumor cell transendothelial migration, and lung metastasis. Therefore, ICAM1 can serve as a novel therapeutic target for metastasis initiation of TNBC.

Circulating tumor cell (CTC) clusters are more efficient at mediating metastasis as compared to single cells and are associated with poor prognosis in breast cancer. Here, the authors show that ICAM1 is enriched in CTC clusters and its loss suppresses cell-cell interaction and CTC cluster formation, and propose ICAM1 as a therapeutic target for treating breast cancer metastasis.

A new clinical scale of carpal tunnel syndrome: validation of the measurement and clinical-neurophysiological assessment

OBJECTIVE

To validate a new clinical scale of carpal tunnel syndrome (CTS). The scale is based on clinical history and physical examination findings and includes two figures. The first is a score determined by clinical history and objective findings. The second evaluates the presence/absence of pain as a dichotomous categorical score.

METHODS

One hundred and sixty-eight consecutive idiopathic CTS hands were studied in two centers (Rome, Siena). We compare the results of the historical-objective scale (Hi-Ob scale) with the results of other validated measurements of CTS severity: (1) the Italian version of the Boston Carpal Tunnel Questionnaire, (2) the neurophysiological classification adopted by the Italian CTS study group. Furthermore, for the Hi-Ob scale the intra-observer and inter-observer evaluations were assessed.

RESULTS

The main Hi-Ob parameter was positively related to the conventional validated measurements. Conversely, the category 'PAIN' of the Hi-Ob scale appeared unrelated to the other clinical and electrophysiological parameters. Intra- and inter-observer evaluation showed the reproducibility of the Hi-Ob assessment.

CONCLUSIONS

Our data show that the Hi-Ob scale is a reliable measurement which may be useful in CTS evaluation either for clinical or for scientific purposes.

Clinical usefulness of intravenous human immunoglobulins in invasive group A Streptococcal infections: case report and review

The spectrum of invasive Streptococcus pyogenes (group A streptococcus) infections includes bacteremia, toxic shock syndrome, and necrotizing fasciitis or myositis. We report the successful use of intravenous immunoglobulins in conjunction with antibiotics and surgery in a case of necrotizing myositis, toxic shock, and bacteremia. A literature review revealed that three other patients with invasive group A streptococcal infections had been treated with immunoglobulins: one adult patient had toxic shock syndrome, one had necrotizing fasciitis, and one child had septic arthritis. On the basis of this report and the review, we suggest that intravenous immunoglobulins may be useful in the treatment of all forms of invasive group A streptococcal infections associated with toxic shock syndrome.

Enzyme profile of rat bile ductular epithelial cells in reference to the resistance phenotype in hepatocarcinogenesis

An extensive bile ductular cell hyperplasia with the formation of well-differentiated bile ductules is the most prominent feature of rat liver at 6 to 15 weeks after bile duct ligation. We have improved our previous cell isolation procedure and are now routinely able to obtain from such livers high yields of viable bile ductular epithelial cells. These cells were characterized with respect to their specific activities of gamma-glutamyl transpeptidase and beta-glucuronidase and of select Phase I and Phase II enzymes of biotransformation. At the time of their isolation, only a very small number of the bile ductular epithelial cells were observed to be in DNA synthesis. In addition, in histological sections prepared from intact hyperplastic bile ductular tissue isolates, only the bile ductular epithelial cells exhibited histochemical staining for gamma-glutamyl transpeptidase activity. Typically, greater than 95% of the cells isolated from this tissue were also found to be histochemically positive for gamma-glutamyl transpeptidase activity, and no hepatocytes were seen contaminating this cell population. Biochemically, the isolated bile ductular cells exhibited a gamma-glutamyl transpeptidase specific activity that was 100 times higher than that of hepatocytes isolated at the same time from the bile duct-ligated rats and more than 300 times higher than the specific activity of the enzyme of freshly isolated normal rat hepatocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

Peroneal mononeuropathy: predisposing factors, and clinical and neurophysiological relationships

The most common mononeuropathy in the lower extremity involves the nerve. We retrospectively evaluated the etiological predisposing factors and clinical-neurophysiological features of 36 patients affected by peroneal mononeuropathy (PM). In 30 patients, a clear predisposing factor was identified. PM was more frequently perioperative (11 cases), associated with axonal involvement. Unexpectedly, PM was not only due to surgery close to the peroneal region, but was mostly associated with hip surgery and, rarely, with thoracic-abdominal surgery. A postural predisposing factor of PM was also frequently observed, usually associated with a pure conduction block. Conversely, most patients with bedridden predisposing factor presented axonal involvement, which was rarely associated with conduction block. In 25 of 36 PM cases, a long-term follow-up lead to an improvement (12 cases) or to good recovery (13 cases) of PM. In conclusion, our study shows that: (1) in most PM cases it is possible to identify a predisposing factor; (2) there is a good correlation between predisposing factor and neurophysiological involvement, and (3) PM usually has usually a good prognosis.

Neurophysiological classification of ulnar entrapment across the elbow

Ulnar nerve entrapment across the elbow (UAE), a common entrapment, requires neurophysiological evaluation for a diagnosis, but a standardised neurophysiological classification is not available. The aim of our study was to evaluate the validity of a neurophysiological classification of UAE, developed by us. To this end, we examined whether sensorimotor deficits, as observed by the physician and as referred by the patients, increased with the neurophysiological severity according to the classification. We performed a multiperspective assessment of 63 consecutive arms from 52 patients with a clinical diagnosis of UAE. Neurophysiological, clinical and patient-oriented validated measurements were used. The neurophysiological classification is based on the presence or absence of evoked responses and on the normality or abnormality of conduction findings. A strict relationship was observed between the degree of neurophysiological severity and the clinical findings (sensorimotor deficits). Moreover, a significant positive correlation between hand functional deficit and neurophysiological classification was observed. Conversely, a clear correlation between neurophysiological pattern and symptoms was not found. The neurophysiological classification is easy to use and reliable, but further multicentric studies should be performed.

Lectin histochemistry of the Drosophila embryo

A selection of lectins was used to characterise changes in the distribution of glycoconjugates during the embryonic development of Drosophila melanogaster. The blastoderm of pre-gastrulation embryos bound low levels of the lectins LPA, UEA-I and PNA. The germ line progenitors (pole cells) bound ConA, PNA and LPA. The yolk granules, the trachea, and the gut bound GSA-I. All lectins had detectable labeling of the ectoderm. The somata of the nervous system bound ConA and LPA. Electron microscopic analysis of PNA labeling of the nervous system revealed exclusive binding to the axon tracts and ensheathing glia. Hyaluronate lyase digestion of oligosaccharides revealed gut and nervous system binding with WGA and UEA-I. This study revealed useful biochemical probes of gut, epidermal and nervous system development that identify the distribution of likely ligands for as yet uncharacterised endogenous lectins.

Carpal tunnel syndrome: relationship between clinical and patient-oriented assessment

Clinical diagnosis of carpal tunnel syndrome usually is easy and sensitive, but frequently, it is based on history and referred symptoms when no motor or sensory deficits are observed during examination. In patients with carpal tunnel syndrome, a dissociation between the severity of the disease reported by the patient and the deficits clinically evaluated by the physician often are observed. The Italian Carpal Tunnel Syndrome Study Group did a multicenter study on 740 patients (1123 hands) with carpal tunnel syndrome to assess the aspects of dissociation between the patient's and the physician's quantification of the disease severity and the ability of the patients with carpal tunnel syndrome to do daily activities. Validated patient-oriented parameters assessing symptoms and hand functional status were used. The relationship between the physician's and the patient's measurements is strong with a linear significant correlation when analyzing the functional status of the hand but not so clear and simple when analyzing the symptoms. Patients with mild-to-moderate carpal tunnel syndrome seemed to function well, although severe symptoms may be reported by the patient; however, when nerve impairment becomes severe, the patient's hand function is extremely impaired although symptoms may be milder. The data show that the patient's point of view is reliable. Carpal tunnel syndrome seems to be an ideal model to evaluate the importance of patient-oriented measurements.

A prospective imaging study of 131I-B72.3 monoclonal antibody in patients with epithelial ovarian cancer: preliminary report

Twenty patients with known ovarian cancer have been investigated in this pilot study to verify the clinical usefulness of radioimaging using the B72.3 monoclonal antibody labelled with iodine-131. No adverse reactions occurred after intravenous injection of B72.3 MoAb. The radioimaging results were compared with those obtained with other diagnostic methods, including computed X-ray tomography and ultrasound. A sensitivity of 85% in the detection of primary ovarian cancers and collections of ascites, and of 84% in the detection of abdominal and extraperitoneal metastases has been demonstrated using this radioiodinated antibody in vivo. No false localization occurred. Immunohistochemical studies showed no cross-reactions between B72.3 MoAb and mesothelial cells, confirming the high specificity of binding between B72.3 MoAb and neoplastic cells in ascites. Negligible uptake of radiolabelled B72.3 MoAb has been demonstrated in the unaffected ovary. The major advantage of using this monoclonal antibody is related to the expression of a recognized antigen (called TAG 72) in mucinous, serous and in differentiated adenocarcinomas of the ovary.

MRI of the small-bowel: how to differentiate primary neoplasms and mimickers

MRI of the gastrointestinal tract is gaining clinical acceptance and is increasingly used to evaluate patients with suspected small-bowel diseases. MRI may be performed with enterography or enteroclysis, both of which combine the advantages of cross-sectional imaging with those of conventional enteroclysis. In this paper, MRI features of primary small-bowel neoplasms, the most important signs for differential diagnosis and the diseases that can be considered as mimickers of small-bowel neoplasms, are discussed.

Specificity of substrate recognition by Pseudomonas fluorescens N3 dioxygenase. The role of the oxidation potential and molecular geometry

Pseudomonas fluorescens N3 is able to grow on naphthalene as the sole carbon and energy source. The mutant TTC1, blocked at the dihydrodiol dehydrogenase level, which can transform the hydrocarbon into the corresponding dihydrodiol, has been used to produce bioconversion products. To rationalize the different grades of conversion obtained with different substrates, a study was performed using non-naphthalene derivatives, including benzenes, conjugated benzenes, and polycyclic aromatic hydrocarbons. The corresponding diols obtained by bioconversion have been isolated and characterized. A theoretical model that considers both energy and geometry factors has been proposed to rationalize the experimental data. Good agreement has been found between the calculated values and the experimental results.

Patient-oriented assessment of back pain in pregnancy

Back pain is a common symptom in women during the last period of pregnancy. Only a few studies using validated patient-oriented tools have been undertaken on this topic. We report on a multicenter study on back pain in women during the last period of pregnancy, which involved seven Italian institutions. Seventy-six women in their 8th and 9th months were studied using the Italian validated version of the Roland questionnaire -- a disease-specific patient-oriented tool for low back pain. Sixty-two percent of the women had gone through at least one previous pregnancy, and clinical data concerning both the period before all pregnancies and the period before the current pregnancy were acquired. The study found that 31% of the women had no back pain symptoms (Roland score 0), 40% scored from 1 to 4, 21% scored from 5 to 10, and 8% scored more than 10. With regard to the predictive factor, history of back pain and sciatica before the pregnancy were found to be associated with occurrence of back pain symptoms during pregnancy. Unexpectedly, our results showed that male sex of the fetus seems to be related to occurrence of back pain symptoms during pregnancy. However, back pain was not associated with having gone through previous pregnancies, nor was the Roland score related to the weight before pregnancy or to increment of weight during pregnancy. Evaluation of the patient's perspective made it possible to identify predictive factors for occurrence of back pain, thereby furnishing important information for the clinical approach to pregnancy.

Liver toxicity in the era of immune checkpoint inhibitors: A practical approach

Immune checkpoint inhibitors have revolutionized the cancer treatment with an approved efficacy in different solid tumors and hematologic malignancies. These agents are increasing the indication in cancer treatment, but can be associated with serious immune-related adverse effects (IRAEs). Dermatologic and gastrointestinal toxicities are the most common IRAE followed by endocrinopathies with a different time of occurrence. Rarely cases of gastrointestinal toxicities are observed almost 2 years after initiation of the therapy. In this review we focus on liver toxicity related to these immunotherapeutic agents for which the largest amount of safety data is available. The management of drug-induced liver toxicity is very complicated and in same cases may take a long period of time to be resolved. A prompt recognition of liver IRAEs and an appropriate management of this event, requiring close collaboration with other specialist figures, could improve its treatment with evident implication on the efficacy of the therapy.

Dynamic Glycoprotein Hyposialylation Promotes Chemotherapy Evasion and Metastatic Seeding of Quiescent Circulating Tumor Cell Clusters in Breast Cancer

Most circulating tumor cells (CTC) are detected as single cells, whereas a small proportion of CTCs in multicellular clusters with stemness properties possess 20- to 100-times higher metastatic propensity than the single cells. Here we report that CTC dynamics in both singles and clusters in response to therapies predict overall survival for breast cancer. Chemotherapy-evasive CTC clusters are relatively quiescent with a specific loss of ST6GAL1-catalyzed α2,6-sialylation in glycoproteins. Dynamic hyposialylation in CTCs or deficiency of ST6GAL1 promotes cluster formation for metastatic seeding and enables cellular quiescence to evade paclitaxel treatment in breast cancer. Glycoproteomic analysis reveals newly identified protein substrates of ST6GAL1, such as adhesion or stemness markers PODXL, ICAM1, ECE1, ALCAM1, CD97, and CD44, contributing to CTC clustering (aggregation) and metastatic seeding. As a proof of concept, neutralizing antibodies against one newly identified contributor, PODXL, inhibit CTC cluster formation and lung metastasis associated with paclitaxel treatment for triple-negative breast cancer.

SIGNIFICANCE

This study discovers that dynamic loss of terminal sialylation in glycoproteins of CTC clusters contributes to the fate of cellular dormancy, advantageous evasion to chemotherapy, and enhanced metastatic seeding. It identifies PODXL as a glycoprotein substrate of ST6GAL1 and a candidate target to counter chemoevasion-associated metastasis of quiescent tumor cells. This article is featured in Selected Articles from This Issue, p. 1949.

A useful electrophysiological test for diagnosis of minimal conduction block

OBJECTIVE

To evaluate the usefulness, sensitivity and specificity of a new neurophysiological test for partial conduction block. METHODS. In 17 patients (17 nerves) with clinical pictures strongly suggesting the presence of motor conduction block and 20 healthy subjects (40 nerves), motor nerve conduction studies were performed with the conventional surface technique and with a new technique developed by us: the single fiber EMG (SFEMG) conduction block test. Moreover, we also evaluated patients with other neurological diseases. The recent American Association of Electrodiagnostic Medicine (AAEM) consensus criteria for partial conduction block were used for the standard conduction block tests.

RESULTS

According to AAEM consensus criteria, 5/17 cases presented 'definite' partial conduction block and 6 presented 'probable' partial conduction block. In contrast, 16/17 cases (94%) presented evidence of conduction block at the SFEMG conduction block test. The 5/6 cases that did not fulfill in the AAEM criteria and that presented abnormal findings at SFEMG nerve conduction test could be considered affected by minimal conduction block. The sensitivity of this new test was greater than conventional test. The specificity was 100% (no abnormal findings in healthy subjects or patients with diseases other than neuropathy).

CONCLUSIONS

The SFEMG conduction block test is a sensitive, complementary, technique for diagnosis of minimal conduction block in patients with normal findings in standard nerve conduction studies.

Multiperspective assessment of peripheral nerve involvement in diabetic patients

To assess the relationship between peripheral nerve involvement and the patient's perception of his own quality of life, we studied 36 consecutive out-patients affected by insulin-dependent diabetes mellitus without other diabetic complications other than neuropathy (20 men, 16 women; mean age 39.1 years). We used clinical (Semmes-Weinstein, vibration perception threshold, muscle strength, osteotendinous reflexes), neurophysiological (sural, peroneal and ulnar nerves), metabolic (glycosylated haemoglobin) and patient-oriented (SF-36 and NASS questionnaires) measurements. Patient-oriented physical scores were significantly related to: (1) neurophysiological findings of the inferior limbs; (2) conventional measurements of sensitivity; (3) metabolic assessment. Conversely, patient-oriented mental scores were significantly related only to metabolic assessment. The patient-oriented measure provided an important perspective of the severity of the disease often closely related with the biological parameters and suggested new ways of interpreting conventional biological measurements. In particular, the peripheral nerve picture appeared strictly related with the physical aspects of the patients' quality of life, while the metabolic picture appeared related with both the mental and physical aspects of the quality of life.

Orthofile®: a new approach for mechanical interproximal reduction : a scanning electron microscopic enamel evaluation

PURPOSE

The aim of this in vitro study was to evaluate the stripping achieved on different teeth (incisors, canines, and premolars) by two grades of abrasive strips used for the first and tenth time. Our second aim was to test the efficacy of these strips by calculating the time necessary to perform interproximal reductions of 0.10, 0.20, and 0.30 mm.

METHODS

Four models were constructed using extracted teeth affixed in wax. The upper and lower arches were set on plaster bases and fixed in wax, carefully creating contact points. All model mouths were treated with artificial saliva (Oral Balance®) in order to simulate the biological conditions in the oral cavity. We then tested specific air-rotor strips of different grades and degrees of wear (15-µm-grain and 25-µm-grain Orthofile® strips). Afterwards the teeth from all samples were cut lengthwise in half, and each mesial and distal portion was gold-plated and observed under SEM at incremental magnification (30, 60, and 100 µm).

RESULTS

The 25-µm-grain strip was more effective than the 15-µm-grain strip, irrespective of the tooth involved. Second, the finishing phase with specific polishing strips after interproximal reduction was fundamental in reducing the number of abrasions and irregularities created by stripping, in particular after using the 25-µm-grain strip. To achieve the best result, the entire abraded area must be polished.

CONCLUSION

This system permits a rapid and effective stripping procedure in direct proportion to the strip's grain and in inverse proportion to the wear from its use. Further research will enable us to compare this system with similar procedures.

Unique molecular signatures sustained in circulating monocytes and regulatory T cells in convalescent COVID-19 patients

Over two years into the COVID-19 pandemic, the human immune response to SARS-CoV-2 during the active disease phase has been extensively studied. However, the long-term impact after recovery, which is critical to advance our understanding SARS-CoV-2 and COVID-19-associated long-term complications, remains largely unknown. Herein, we characterized single-cell profiles of circulating immune cells in the peripheral blood of 100 patients, including convalescent COVID-19 and sero-negative controls. Flow cytometry analyses revealed reduced frequencies of both short-lived monocytes and long-lived regulatory T (Treg) cells within the patients who have recovered from severe COVID-19. sc-RNA seq analysis identifies seven heterogeneous clusters of monocytes and nine Treg clusters featuring distinct molecular signatures in association with COVID-19 severity. Asymptomatic patients contain the most abundant clusters of monocytes and Tregs expressing high CD74 or IFN-responsive genes. In contrast, the patients recovered from a severe disease have shown two dominant inflammatory monocyte clusters featuring S100 family genes: one monocyte cluster of S100A8 & A9 coupled with high HLA-I and another cluster of S100A4 & A6 with high HLA-II genes, a specific non-classical monocyte cluster with distinct IFITM family genes, as well as a unique TGF-β high Treg Cluster. The outpatients and seronegative controls share most of the monocyte and Treg clusters patterns with high expression of HLA genes. Surprisingly, while presumably short-lived monocytes appear to have sustained alterations over 4 months, the decreased frequencies of long-lived Tregs (high HLA-DRA and S100A6) in the outpatients restore over the tested convalescent time (≥ 4 months). Collectively, our study identifies sustained and dynamically altered monocytes and Treg clusters with distinct molecular signatures after recovery, associated with COVID-19 severity.

Cyclin-Dependent Kinase 4/6 Inhibitors Beyond Progression in Metastatic Breast Cancer: A Retrospective Real-World Biomarker Analysis

PURPOSE

As the continuation beyond progression (BP) of cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) is becoming increasingly attractive for the treatment of patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer (MBC), the definition of resistance factors is crucial. The aim of the study was to investigate the impact of CDK 4/6i BP and to explore potential genomic stratification factors.

MATERIALS AND METHODS

We retrospectively analyzed a multi-institutional cohort of patients with HR-positive HER2-negative MBC characterized for circulating tumor DNA through next-generation sequencing before treatment start. Differences across subgroups were analyzed by chi-square test, and survival was tested by univariable and multivariable Cox regression. Further correction was applied by propensity score matching.

RESULTS

Among the 214 patients previously exposed to CDK4/6i, 172 were treated with non-CDK4/6i-based treatment (non-CDK) and 42 with CDK4/6i BP. Multivariable analysis showed a significant impact of CDK4/6i BP, TP53 single-nucleotide variants, liver involvement, and treatment line on both progression-free survival (PFS) and overall survival (OS). Propensity score matching confirmed the prognostic role of CDK4/6i BP both for PFS and OS. The favorable impact of CDK4/6i BP was consistent across all subgroups, and a differential benefit was suggested for ESR1-mutated patients. ESR1 and RB1 mutations were more represented in the CDK4/6i BP subgroup with respect to CDK4/6i upfront.

CONCLUSION

The study highlighted a significant prognostic impact of the CDK4/6i BP strategy with a potential added benefit in patients with ESR1 mutations suggesting the need for an extensive biomarker characterization.